1
|
Hönicke P, Wählisch A, Unterumsberger R, Beckhoff B, Bogdanowicz J, Charley AL, Mertens H, Rochat N, Hartmann JM, Giambacorti N. Reference-free x-ray fluorescence analysis with a micrometer-sized incident beam. Nanotechnology 2024; 35:285702. [PMID: 38579688 DOI: 10.1088/1361-6528/ad3aff] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 04/05/2024] [Indexed: 04/07/2024]
Abstract
Spatially resolved x-ray fluorescence (XRF) based analysis employing incident beam sizes in the low micrometer range (μXRF) is widely used to study lateral composition changes of various types of microstructured samples. However, up to now the quantitative analysis of such experimental datasets could only be realized employing adequate calibration or reference specimen. In this work, we extent the applicability of the so-called reference-free XRF approach to enable reference-freeμXRF analysis. Here, no calibration specimen are needed in order to derive a quantitative and position sensitive composition of the sample of interest. The necessary instrumental steps to realize reference-freeμXRF are explained and a validation of ref.-freeμXRF against ref.-free standard XRF is performed employing laterally homogeneous samples. Finally, an application example from semiconductor research is shown, where the lateral sample features require the usage of ref.-freeμXRF for quantitative analysis.
Collapse
Affiliation(s)
- Philipp Hönicke
- Physikalisch-Technische Bundesanstalt (PTB) Abbestr. 2-12 D-10587 Berlin, Germany
| | - André Wählisch
- Physikalisch-Technische Bundesanstalt (PTB) Abbestr. 2-12 D-10587 Berlin, Germany
| | | | - Burkhard Beckhoff
- Physikalisch-Technische Bundesanstalt (PTB) Abbestr. 2-12 D-10587 Berlin, Germany
| | | | | | | | - Névine Rochat
- Univ. Grenoble Alpes CEA, Leti F-38000 Grenoble, France
| | | | | |
Collapse
|
2
|
Calogero G, Raciti D, Ricciarelli D, Acosta-Alba P, Cristiano F, Daubriac R, Demoulin R, Deretzis I, Fisicaro G, Hartmann JM, Kerdilès S, La Magna A. Atomistic Insights into Ultrafast SiGe Nanoprocessing. J Phys Chem C Nanomater Interfaces 2023; 127:19867-19877. [PMID: 37817920 PMCID: PMC10561275 DOI: 10.1021/acs.jpcc.3c05999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 09/13/2023] [Indexed: 10/12/2023]
Abstract
Controlling ultrafast material transformations with atomic precision is essential for future nanotechnology. Pulsed laser annealing (LA), inducing extremely rapid and localized phase transitions, is a powerful way to achieve this but requires careful optimization together with the appropriate system design. We present a multiscale LA computational framework that can simulate atom-by-atom the highly out-of-equilibrium kinetics of a material as it interacts with the laser, including effects of structural disorder. By seamlessly coupling a macroscale continuum solver to a nanoscale superlattice kinetic Monte Carlo code, this method overcomes the limits of state-of-the-art continuum-based tools. We exploit it to investigate nontrivial changes in composition, morphology, and quality of laser-annealed SiGe alloys. Validations against experiments and phase-field simulations as well as advanced applications to strained, defected, nanostructured, and confined SiGe are presented, highlighting the importance of a multiscale atomistic-continuum approach. Current applicability and potential generalization routes are finally discussed.
Collapse
Affiliation(s)
| | - Domenica Raciti
- STMicroelectronics, Stradale Primosole 50, 95121 Catania, Italy
| | | | | | | | | | - Remi Demoulin
- Univ
Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, GPM UMR 6634, F-76000 Rouen, France
| | | | | | | | | | | |
Collapse
|
3
|
Poempool T, Aberl J, Clementi M, Spindlberger L, Vukušić L, Galli M, Gerace D, Fournel F, Hartmann JM, Schäffler F, Brehm M, Fromherz T. Single SiGe quantum dot emission deterministically enhanced in a high-Q photonic crystal resonator. Opt Express 2023; 31:15564-15578. [PMID: 37157655 DOI: 10.1364/oe.480281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We report the resonantly enhanced radiative emission from a single SiGe quantum dot (QD), which is deterministically embedded into a bichromatic photonic crystal resonator (PhCR) at the position of its largest modal electric field by a scalable method. By optimizing our molecular beam epitaxy (MBE) growth technique, we were able to reduce the amount of Ge within the whole resonator to obtain an absolute minimum of exactly one QD, accurately positioned by lithographic methods relative to the PhCR, and an otherwise flat, a few monolayer thin, Ge wetting layer (WL). With this method, record quality (Q) factors for QD-loaded PhCRs up to Q ∼ 105 are achieved. A comparison with control PhCRs on samples containing a WL but no QDs is presented, as well as a detailed analysis of the dependence of the resonator-coupled emission on temperature, excitation intensity, and emission decay after pulsed excitation. Our findings undoubtedly confirm a single QD in the center of the resonator as a potentially novel photon source in the telecom spectral range.
Collapse
|
4
|
Reed ZD, Tran H, Ngo HN, Hartmann JM, Hodges JT. Effect of Non-Markovian Collisions on Measured Integrated Line Shapes of CO. Phys Rev Lett 2023; 130:143001. [PMID: 37084433 DOI: 10.1103/physrevlett.130.143001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 01/25/2023] [Accepted: 03/10/2023] [Indexed: 05/03/2023]
Abstract
Using cavity ring-down spectroscopy to probe R-branch transitions of CO in N_{2}, we show that the spectral core of the line shapes associated with the first few rotational quantum numbers, J, can be accurately modeled using a sophisticated line profile, provided that a pressure-dependent line area is introduced. This correction vanishes as J increases and is always negligible in CO-He mixtures. The results are supported by molecular dynamics simulations attributing the effect to non-Markovian behavior of collisions at short times. This work has large implications because corrections must be considered for accurate determinations of integrated line intensities, and for spectroscopic databases and radiative transfer codes used for climate predictions and remote sensing.
Collapse
Affiliation(s)
- Zachary D Reed
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Ha Tran
- Laboratoire de Météorologie Dynamique/IPSL, CNRS, Sorbonne Université, Ecole Polytechnique, Institut polytechnique de Paris, Ecole Normale Supérieure, PSL Research University, 4 place Jussieu, 75252, Paris, France
| | - Hoa N Ngo
- Faculty of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi, Vietnam
| | - Jean-Michel Hartmann
- Laboratoire de Météorologie Dynamique/IPSL, CNRS, Sorbonne Université, Ecole Polytechnique, Institut polytechnique de Paris, Ecole Normale Supérieure, PSL Research University, 4 place Jussieu, 75252, Paris, France
| | - Joseph T Hodges
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| |
Collapse
|
5
|
Wind L, Sistani M, Böckle R, Smoliner J, Vukŭsić L, Aberl J, Brehm M, Schweizer P, Maeder X, Michler J, Fournel F, Hartmann JM, Weber WM. Composition Dependent Electrical Transport in Si 1-x Ge x Nanosheets with Monolithic Single-Elementary Al Contacts. Small 2022; 18:e2204178. [PMID: 36135726 DOI: 10.1002/smll.202204178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/25/2022] [Indexed: 06/16/2023]
Abstract
Si1-x Gex is a key material in modern complementary metal-oxide-semiconductor and bipolar devices. However, despite considerable efforts in metal-silicide and -germanide compound material systems, reliability concerns have so far hindered the implementation of metal-Si1-x Gex junctions that are vital for diverse emerging "More than Moore" and quantum computing paradigms. In this respect, the systematic structural and electronic properties of Al-Si1-x Gex heterostructures, obtained from a thermally induced exchange between ultra-thin Si1-x Gex nanosheets and Al layers are reported. Remarkably, no intermetallic phases are found after the exchange process. Instead, abrupt, flat, and void-free junctions of high structural quality can be obtained. Interestingly, ultra-thin interfacial Si layers are formed between the metal and Si1-x Gex segments, explaining the morphologic stability. Integrated into omega-gated Schottky barrier transistors with the channel length being defined by the selective transformation of Si1-x Gex into single-elementary Al leads, a detailed analysis of the transport is conducted. In this respect, a report on a highly versatile platform with Si1-x Gex composition-dependent properties ranging from highly transparent contacts to distinct Schottky barriers is provided. Most notably, the presented abrupt, robust, and reliable metal-Si1-x Gex junctions can open up new device implementations for different types of emerging nanoelectronic, optoelectronic, and quantum devices.
Collapse
Affiliation(s)
- Lukas Wind
- Institute of Solid State Electronics, Technische Universität Wien, Gußhausstraße 25-25a, Vienna, 1040, Austria
| | - Masiar Sistani
- Institute of Solid State Electronics, Technische Universität Wien, Gußhausstraße 25-25a, Vienna, 1040, Austria
| | - Raphael Böckle
- Institute of Solid State Electronics, Technische Universität Wien, Gußhausstraße 25-25a, Vienna, 1040, Austria
| | - Jürgen Smoliner
- Institute of Solid State Electronics, Technische Universität Wien, Gußhausstraße 25-25a, Vienna, 1040, Austria
| | - Lada Vukŭsić
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, Linz, 4040, Austria
| | - Johannes Aberl
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, Linz, 4040, Austria
| | - Moritz Brehm
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, Linz, 4040, Austria
| | - Peter Schweizer
- Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkstrasse 39, Thun, 3602, Switzerland
| | - Xavier Maeder
- Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkstrasse 39, Thun, 3602, Switzerland
| | - Johann Michler
- Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkstrasse 39, Thun, 3602, Switzerland
| | - Frank Fournel
- CEA-LETI, University Grenoble Alpes, 17 Avenue des Martyrs, Grenoble, 38000, France
| | - Jean-Michel Hartmann
- CEA-LETI, University Grenoble Alpes, 17 Avenue des Martyrs, Grenoble, 38000, France
| | - Walter M Weber
- Institute of Solid State Electronics, Technische Universität Wien, Gußhausstraße 25-25a, Vienna, 1040, Austria
| |
Collapse
|
6
|
Bonino V, Pauc N, Calvo V, Frauenrath M, Hartmann JM, Chelnokov A, Reboud V, Rosenthal M, Segura-Ruiz J. Microstructuring to Improve the Thermal Stability of GeSn Layers. ACS Appl Mater Interfaces 2022; 14:22270-22277. [PMID: 35510890 DOI: 10.1021/acsami.2c01652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Tin segregation in Ge1-xSnx alloys is one of the major problems potentially hindering the use of this material in devices. Ge1-xSnx microdisks fabricated from layers with Sn concentrations up to 16.9% underwent here annealing at temperatures as high as 400 °C for 20 min without Sn segregation, in contrast with the full segregation observed in the corresponding blanket layers annealed simultaneously. After annealing, no changes in the elemental composition of the microdisks were evidenced. An enhancement of the total integrated photoluminescence, with no modifications of the emission energy, was also observed. These findings show that microstructuring offers a completely new path in maintaining the stability of high Sn concentration Ge1-xSnx layers at temperatures much higher than those used for growth. This approach enables the use of thermal annealing processes to improve the properties of this alloy in optoelectronic devices (such as light emitting diodes, lasers, photodetectors, or modulators). It should also facilitate the integration of Ge1-xSnx into well-established technologies requiring medium temperature processes. The same strategy may help to prevent Sn segregation during high temperature processes in similar metastable alloys.
Collapse
Affiliation(s)
- Valentina Bonino
- ESRF - The European Synchrotron, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Nicolas Pauc
- University of Grenoble Alpes, CEA, Grenoble INP, IRIG, PHELIQS, 38000 Grenoble, France
| | - Vincent Calvo
- University of Grenoble Alpes, CEA, Grenoble INP, IRIG, PHELIQS, 38000 Grenoble, France
| | | | | | - Alexei Chelnokov
- University of Grenoble Alpes, CEA, LETI, F-38054 Grenoble, France
| | - Vincent Reboud
- University of Grenoble Alpes, CEA, LETI, F-38054 Grenoble, France
| | - Martin Rosenthal
- ESRF - The European Synchrotron, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Jaime Segura-Ruiz
- ESRF - The European Synchrotron, 71 Avenue des Martyrs, 38000 Grenoble, France
| |
Collapse
|
7
|
Wang B, Sakat E, Herth E, Gromovyi M, Bjelajac A, Chaste J, Patriarche G, Boucaud P, Boeuf F, Pauc N, Calvo V, Chrétien J, Frauenrath M, Chelnokov A, Reboud V, Hartmann JM, El Kurdi M. GeSnOI mid-infrared laser technology. Light Sci Appl 2021; 10:232. [PMID: 34785641 PMCID: PMC8595695 DOI: 10.1038/s41377-021-00675-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 10/25/2021] [Accepted: 10/29/2021] [Indexed: 06/13/2023]
Abstract
GeSn alloys are promising materials for CMOS-compatible mid-infrared lasers manufacturing. Indeed, Sn alloying and tensile strain can transform them into direct bandgap semiconductors. This growing laser technology however suffers from a number of limitations, such as poor optical confinement, lack of strain, thermal, and defects management, all of which are poorly discussed in the literature. Herein, a specific GeSn-on-insulator (GeSnOI) stack using stressor layers as dielectric optical claddings is demonstrated to be suitable for a monolithically integration of planar Group-IV semiconductor lasers on a versatile photonic platform for the near- and mid-infrared spectral range. Microdisk-shape resonators on mesa structures were fabricated from GeSnOI, after bonding a Ge0.9Sn0.1 alloy layer grown on a Ge strain-relaxed-buffer, itself on a Si(001) substrate. The GeSnOI microdisk mesas exhibited significantly improved optical gain as compared to that of conventional suspended microdisk resonators formed from the as-grown layer. We further show enhanced vertical out-coupling of the disk whispering gallery mode in-plane radiation, with up to 30% vertical out-coupling efficiency. As a result, the GeSnOI approach can be a valuable asset in the development of silicon-based mid-infrared photonics that combine integrated sources in a photonic platform with complex lightwave engineering.
Collapse
Affiliation(s)
- Binbin Wang
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France
| | - Emilie Sakat
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France
| | - Etienne Herth
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France
| | - Maksym Gromovyi
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France
| | - Andjelika Bjelajac
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France
| | - Julien Chaste
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France
| | - Gilles Patriarche
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France
| | - Philippe Boucaud
- Université Côte d'Azur, CNRS, CRHEA, Rue Bernard Grégory, 06905, Sophia-Antipolis, France
| | - Frédéric Boeuf
- STMicroelectronics, Rue Jean Monnet, 38054, Crolles, France
| | - Nicolas Pauc
- Université Grenoble Alpes, CEA, IRIG-DePhy, 17 rue des Martyrs, 38000, Grenoble, France
| | - Vincent Calvo
- Université Grenoble Alpes, CEA, IRIG-DePhy, 17 rue des Martyrs, 38000, Grenoble, France
| | - Jérémie Chrétien
- Université Grenoble Alpes, CEA, IRIG-DePhy, 17 rue des Martyrs, 38000, Grenoble, France
| | - Marvin Frauenrath
- Université Grenoble Alpes, CEA, Leti, 17 rue des Martyrs, 38000, Grenoble, France
| | - Alexei Chelnokov
- Université Grenoble Alpes, CEA, Leti, 17 rue des Martyrs, 38000, Grenoble, France
| | - Vincent Reboud
- Université Grenoble Alpes, CEA, Leti, 17 rue des Martyrs, 38000, Grenoble, France
| | - Jean-Michel Hartmann
- Université Grenoble Alpes, CEA, Leti, 17 rue des Martyrs, 38000, Grenoble, France
| | - Moustafa El Kurdi
- Université Paris-Saclay, CNRS, C2N, 10 boulevard Thomas Gobert, 91120, Palaiseau, France.
| |
Collapse
|
8
|
Quintero A, Gergaud P, Nguyen-Thanh T, Hartmann JM, Reboud V, Cassan E, Rodriguez P. Texture of NiGe(Sn) on Ge(100) and its evolution with Sn content. J Appl Crystallogr 2021. [DOI: 10.1107/s1600576721007172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The texture of the Ni monostanogermanide phase on a Ge(100) substrate was evaluated during a solid-state reaction, with a focus on the impact of Sn addition. Complementary X-ray diffraction analyses involving in situ X-ray diffraction, in-plane reciprocal space maps (RSMs) and pole figures were used to that end. A sequential growth of the phases for the Ni/Ge(Sn) system was found. An Ni-rich phase formed first, followed by the NiGe(Sn) phase. The NiGe and NiGe(Sn) layers were polycrystalline with different out-of-plane orientations. The number of out-of-plane diffraction peaks decreased with the Sn content, while the preferred orientation changed. In-plane RSM analyses confirmed these results. Sn addition modified the out-of-plane and in-plane orientations. Pole figure analysis revealed that numerous epitaxial texture components were present for the Ni/Ge system, while Sn addition reduced the number of epitaxial texture components. On the other hand, segregated Sn crystallized with an epitaxial alignment with the Ge substrate underneath.
Collapse
|
9
|
Benedikovic D, Virot L, Aubin G, Hartmann JM, Amar F, Le Roux X, Alonso-Ramos C, Dado M, Cassan E, Marris-Morini D, Fedeli JM, Boeuf F, Szelag B, Vivien L. Heterostructured silicon-germanium-silicon p-i-n avalanche photodetectors for chip-integrated optoelectronics -INVITED. EPJ Web Conf 2021. [DOI: 10.1051/epjconf/202125501002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Optical photodetectors are at the forefront of photonic research since the rise of integrated optics. Photodetectors are fundamental building blocks for chip-scale optoelectronics, enabling conversion of light into an electrical signal. Such devices play a key role in many surging applications from communication and computation to sensing, biomedicine and health monitoring, to name a few. However, chip integration of optical photodetectors with improved performances is an on-going challenge for mainstream optical communications at near-infrared wavelengths. Here, we present recent advances in heterostructured silicon-germanium-silicon p-i-n photodetectors, enabling high-speed detection on a foundry-compatible monolithic platform.
Collapse
|
10
|
Abouzaid O, Mehdi H, Martin M, Moeyaert J, Salem B, David S, Souifi A, Chauvin N, Hartmann JM, Ilahi B, Morris D, Ahaitouf A, Ahaitouf A, Baron T. O-Band Emitting InAs Quantum Dots Grown By MOCVD On A 300 mm Ge-Buffered Si (001) Substrate. Nanomaterials (Basel) 2020; 10:nano10122450. [PMID: 33297597 PMCID: PMC7762389 DOI: 10.3390/nano10122450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 11/30/2022]
Abstract
The epitaxy of III-V semiconductors on silicon substrates remains challenging because of lattice parameter and material polarity differences. In this work, we report on the Metal Organic Chemical Vapor Deposition (MOCVD) and characterization of InAs/GaAs Quantum Dots (QDs) epitaxially grown on quasi-nominal 300 mm Ge/Si(001) and GaAs(001) substrates. QD properties were studied by Atomic Force Microscopy (AFM) and Photoluminescence (PL) spectroscopy. A wafer level µPL mapping of the entire 300 mm Ge/Si substrate shows the homogeneity of the three-stacked InAs QDs emitting at 1.30 ± 0.04 µm at room temperature. The correlation between PL spectroscopy and numerical modeling revealed, in accordance with transmission electron microscopy images, that buried QDs had a truncated pyramidal shape with base sides and heights around 29 and 4 nm, respectively. InAs QDs on Ge/Si substrate had the same shape as QDs on GaAs substrates, with a slightly increased size and reduced luminescence intensity. Our results suggest that 1.3 μm emitting InAs QDs quantum dots can be successfully grown on CMOS compatible Ge/Si substrates.
Collapse
Affiliation(s)
- Oumaima Abouzaid
- Univ. Grenoble Alpes, CNRS, CEA-Leti, Grenoble INP, LTM, F-38054 Grenoble, France; (O.A.); (H.M.); (M.M.); (J.M.); (S.D.)
- SIGER Laboratory, Faculty of Sciences and Technology, Université Sidi Mohammed Ben Abdellah, Fès BP. 2202, Morocco;
| | - Hussein Mehdi
- Univ. Grenoble Alpes, CNRS, CEA-Leti, Grenoble INP, LTM, F-38054 Grenoble, France; (O.A.); (H.M.); (M.M.); (J.M.); (S.D.)
| | - Mickael Martin
- Univ. Grenoble Alpes, CNRS, CEA-Leti, Grenoble INP, LTM, F-38054 Grenoble, France; (O.A.); (H.M.); (M.M.); (J.M.); (S.D.)
| | - Jérémy Moeyaert
- Univ. Grenoble Alpes, CNRS, CEA-Leti, Grenoble INP, LTM, F-38054 Grenoble, France; (O.A.); (H.M.); (M.M.); (J.M.); (S.D.)
| | - Bassem Salem
- Univ. Grenoble Alpes, CNRS, CEA-Leti, Grenoble INP, LTM, F-38054 Grenoble, France; (O.A.); (H.M.); (M.M.); (J.M.); (S.D.)
- Correspondence: (B.S.); (T.B.)
| | - Sylvain David
- Univ. Grenoble Alpes, CNRS, CEA-Leti, Grenoble INP, LTM, F-38054 Grenoble, France; (O.A.); (H.M.); (M.M.); (J.M.); (S.D.)
| | - Abdelkader Souifi
- Institut des Nanotechnologies de Lyon (INL)-UMR5270-CNRS, Université de Lyon, INSA-Lyon, 7 avenue Jean Capelle, 69621 Villeurbanne, France; (A.S.); (N.C.)
| | - Nicolas Chauvin
- Institut des Nanotechnologies de Lyon (INL)-UMR5270-CNRS, Université de Lyon, INSA-Lyon, 7 avenue Jean Capelle, 69621 Villeurbanne, France; (A.S.); (N.C.)
| | | | - Bouraoui Ilahi
- Institut Quantique et Laboratoire Nanotechnologies Nanosystèmes (LN2)-CNRS UMI-3463, 3IT, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (B.I.); (D.M.)
| | - Denis Morris
- Institut Quantique et Laboratoire Nanotechnologies Nanosystèmes (LN2)-CNRS UMI-3463, 3IT, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (B.I.); (D.M.)
| | - Ali Ahaitouf
- SIGER Laboratory, Faculty of Sciences and Technology, Université Sidi Mohammed Ben Abdellah, Fès BP. 2202, Morocco;
| | - Abdelaziz Ahaitouf
- Faculté Polydisciplinaire Taza, Université Sidi Mohammed Ben Abdellah, LSI, Taza B.P. 1223, Morocco;
| | - Thierry Baron
- Univ. Grenoble Alpes, CNRS, CEA-Leti, Grenoble INP, LTM, F-38054 Grenoble, France; (O.A.); (H.M.); (M.M.); (J.M.); (S.D.)
- Correspondence: (B.S.); (T.B.)
| |
Collapse
|
11
|
Sinobad M, DellaTorre A, Armand R, Luther-Davies B, Ma P, Madden S, Mitchell A, Moss DJ, Hartmann JM, Fedeli JM, Monat C, Grillet C. Mid-infrared supercontinuum generation in silicon-germanium all-normal dispersion waveguides. Opt Lett 2020; 45:5008-5011. [PMID: 32932439 DOI: 10.1364/ol.402159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 08/01/2020] [Indexed: 05/27/2023]
Abstract
We demonstrate coherent supercontinuum generation spanning over an octave from a silicon germanium-on-silicon waveguide using ∼200fs pulses at a wavelength of 4 µm. The waveguide is engineered to provide low all-normal dispersion in the TM polarization. We validate the coherence of the generated supercontinuum via simulations, with a high degree of coherence across the entire spectrum. Such a generated supercontinuum could lend itself to pulse compression down to 22 fs.
Collapse
|
12
|
Quintero A, Gergaud P, Hartmann JM, Delaye V, Reboud V, Cassan E, Rodriguez P. Impact and behavior of Sn during the Ni/GeSn solid-state reaction. J Appl Crystallogr 2020; 53:605-613. [PMID: 32684875 PMCID: PMC7312141 DOI: 10.1107/s1600576720003064] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 03/04/2020] [Indexed: 11/10/2022] Open
Abstract
Ni-based intermetallics are promising materials for forming efficient contacts in GeSn-based Si photonic devices. However, the role that Sn might have during the Ni/GeSn solid-state reaction (SSR) is not fully understood. A comprehensive analysis focused on Sn segregation during the Ni/GeSn SSR was carried out. In situ X-ray diffraction and cross-section transmission electron microscopy measurements coupled with energy-dispersive X-ray spectrometry and electron energy-loss spectroscopy atomic mappings were performed to follow the phase sequence, Sn distribution and segregation. The results showed that, during the SSR, Sn was incorporated into the intermetallic phases. Sn segregation happened first around the grain boundaries (GBs) and then towards the surface. Sn accumulation around GBs hampered atom diffusion, delaying the growth of the Ni(GeSn) phase. Higher thermal budgets will thus be mandatory for formation of contacts in high-Sn-content photonic devices, which could be detrimental for thermal stability.
Collapse
Affiliation(s)
- Andrea Quintero
- Univ. Grenoble Alpes, CEA, LETI, F-38000 Grenoble, France
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France
| | | | | | - Vincent Delaye
- Univ. Grenoble Alpes, CEA, LETI, F-38000 Grenoble, France
| | - Vincent Reboud
- Univ. Grenoble Alpes, CEA, LETI, F-38000 Grenoble, France
| | - Eric Cassan
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France
| | | |
Collapse
|
13
|
Gonzatti F, Hartmann JM, Yckache K. Low and High Temperature Boron and Phosphorous Doping of Si for Junctions and MEMS Purposes. ACTA ACUST UNITED AC 2019. [DOI: 10.1149/1.2986805] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
14
|
Hartmann JM, Papon AM, Colonna JP, Ernst T, Billon T. Growth and Thermal Stability of SiGe/Si Superlattices on Bulk Si Wafers. ACTA ACUST UNITED AC 2019. [DOI: 10.1149/1.2986792] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
15
|
Thai QM, Pauc N, Aubin J, Bertrand M, Chrétien J, Delaye V, Chelnokov A, Hartmann JM, Reboud V, Calvo V. GeSn heterostructure micro-disk laser operating at 230 K. Opt Express 2018; 26:32500-32508. [PMID: 30645416 DOI: 10.1364/oe.26.032500] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/17/2018] [Indexed: 06/09/2023]
Abstract
We demonstrate lasing up to 230 K in a GeSn heterostructure micro-disk cavity. The GeSn 16.0% optically active layer was grown on a step-graded GeSn buffer, limiting the density of misfit dislocations. The lasing wavelengths shifted from 2720 to 2890 nm at 15 K up to 3200 nm at 230 K. Compared to results reported elsewhere, we attribute the increase in maximal lasing temperature to two factors: a stronger optical confinement by a thicker active layer and a better carrier confinement provided by a GeSn 13.8% / GeSn 16.0% / GeSn 13.8% double heterostructure.
Collapse
|
16
|
Quintero A, Gergaud P, Aubin J, Hartmann JM, Reboud V, Rodriguez P. Ni/GeSn solid-state reaction monitored by combined X-ray diffraction analyses: focus on the Ni-rich phase. J Appl Crystallogr 2018. [DOI: 10.1107/s1600576718008786] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The Ni/Ge0.9Sn0.1 solid-state reaction was monitored by combining in situ X-ray diffraction, in-plane reciprocal space map measurements and in-plane pole figures. A sequential growth was shown, in which the first phase formed was an Ni-rich phase. Then, at 518 K, the mono-stanogermanide phase Ni(Ge0.9Sn0.1) was observed. This phase was stable up to 873 K. Special attention has been given to the nature and the crystallographic orientation of the Ni-rich phase obtained at low temperature. It is demonstrated, with in-plane pole figure measurements and simulation, that it was the ɛ-Ni5(Ge0.9Sn0.1)3 metastable phase with a hexagonal structure.
Collapse
|
17
|
Mastari M, Charles M, Bogumilowicz Y, Thai QM, Pimenta-Barros P, Argoud M, Papon AM, Gergaud P, Landru D, Kim Y, Hartmann JM. SiGe nano-heteroepitaxy on Si and SiGe nano-pillars. Nanotechnology 2018; 29:275702. [PMID: 29648544 DOI: 10.1088/1361-6528/aabdca] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this paper, SiGe nano-heteroepitaxy on Si and SiGe nano-pillars was investigated in a 300 mm industrial reduced pressure-chemical vapour deposition tool. An integration scheme based on diblock copolymer patterning was used to fabricate nanometre-sized templates for the epitaxy of Si and SiGe nano-pillars. Results showed highly selective and uniform processes for the epitaxial growth of Si and SiGe nano-pillars. 200 nm thick SiGe layers were grown on Si and SiGe nano-pillars and characterised by atomic force microscopy, x-ray diffraction and transmission electron microscopy. Smooth SiGe surfaces and full strain relaxation were obtained in the 650 °C-700 °C range for 2D SiGe layers grown either on Si or SiGe nano-pillars.
Collapse
Affiliation(s)
- M Mastari
- Univ. Grenoble Alpes, CEA, LETI, F-38000 Grenoble, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Hartmann JM, Boulet C, Tran DD, Tran H, Baranov Y. Effect of humidity on the absorption continua of CO 2 and N 2 near 4 μm: Calculations, comparisons with measurements, and consequences for atmospheric spectra. J Chem Phys 2018; 148:054304. [PMID: 29421910 DOI: 10.1063/1.5019994] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We present a theoretical study of the effects of collisions with water vapor molecules on the absorption, around 4 μm, in both the high frequency wing of the CO2 ν3 band and the collision-induced fundamental band of N2. Calculations are made for the very first time, showing that predictions based on classical molecular dynamics simulations enable, without adjustment of any parameter, very satisfactory agreement with the few available experimental determinations. This opens the route for a future study in which accurate temperature-dependent (semi-empirical) models will be built and checked through comparisons between computed and measured atmospheric spectra. This is of interest since, as demonstrated by simulations, neglecting the humidity of air can lead to significant modifications of the atmospheric transmission (and thus also emission) between 2000 and 2800 cm-1.
Collapse
Affiliation(s)
- Jean-Michel Hartmann
- Laboratoire de Météorologie Dynamique/IPSL, CNRS, Ecole Polytechnique, Université Paris-Saclay, 91128 Palaiseau, France
| | - Christian Boulet
- Institut des Sciences Moléculaires d'Orsay, CNRS, Université Paris-Sud, Université Paris-Saclay, Orsay F-91405, France
| | - Duc Dung Tran
- Laboratoire de Météorologie Dynamique, IPSL, UPMC Univ. Paris 06, Ecole Polytechnique, Ecole Normale Supérieure, Sorbonne Universités, Université Paris-Saclay, PSL Research University, CNRS, 4 Place Jussieu, 75005 Paris, France
| | - Ha Tran
- Laboratoire de Météorologie Dynamique, IPSL, UPMC Univ. Paris 06, Ecole Polytechnique, Ecole Normale Supérieure, Sorbonne Universités, Université Paris-Saclay, PSL Research University, CNRS, 4 Place Jussieu, 75005 Paris, France
| | - Yury Baranov
- SPA "Typhoon," Institute of Experimental Meteorology, 4 Pobeda St., Obninsk, Kaluga Region 249034, Russia
| |
Collapse
|
19
|
Grieb T, Tewes M, Schowalter M, Müller-Caspary K, Krause FF, Mehrtens T, Hartmann JM, Rosenauer A. Quantitative HAADF STEM of SiGe in presence of amorphous surface layers from FIB preparation. Ultramicroscopy 2018; 184:29-36. [DOI: 10.1016/j.ultramic.2017.09.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 09/08/2017] [Accepted: 09/26/2017] [Indexed: 11/27/2022]
|
20
|
Lin K, Ma J, Gong X, Song Q, Ji Q, Zhang W, Li H, Lu P, Li H, Zeng H, Wu J, Hartmann JM, Faucher O, Gershnabel E, Prior Y, Averbukh IS. Rotated echoes of molecular alignment: fractional, high order and imaginary. Opt Express 2017; 25:24917-24926. [PMID: 29041165 DOI: 10.1364/oe.25.024917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 09/25/2017] [Indexed: 06/07/2023]
Abstract
We report experimental observations of rotated echoes of alignment induced by a pair of time-delayed and polarization-skewed femtosecond laser pulses interacting with an ensemble of molecular rotors. Rotated fractional echoes, rotated high order echoes and rotated imaginary echoes are directly visualized by using the technique of coincident Coulomb explosion imaging. We show that the echo phenomenon not only exhibits temporal recurrences but also spatial rotations determined by the polarization of the time-delayed second pulse. The dynamics of echo formation is well described by the laser-induced filamentation in rotational phase space. The quantum-mechanical simulation shows good agreements with the experimental results.
Collapse
|
21
|
Hartmann JM, Tran H. Comment on "Ortho-Para-Dependent Pressure Effects Observed in the Near Infrared Band of Acetylene by Dual-Comb Spectroscopy". Phys Rev Lett 2017; 119:069401. [PMID: 28949626 DOI: 10.1103/physrevlett.119.069401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Indexed: 06/07/2023]
Affiliation(s)
- Jean-Michel Hartmann
- Laboratoire de Météorologie Dynamique / IPLS, CNRS, Ecole Polytechnique, 91128 Palaiseau, France
| | - Ha Tran
- Laboratoire de Météorologie Dynamique / IPLS, CNRS, Ecole Polytechnique, 91128 Palaiseau, France
| |
Collapse
|
22
|
Virot L, Benedikovic D, Szelag B, Alonso-Ramos C, Karakus B, Hartmann JM, Le Roux X, Crozat P, Cassan E, Marris-Morini D, Baudot C, Boeuf F, Fédéli JM, Kopp C, Vivien L. Integrated waveguide PIN photodiodes exploiting lateral Si/Ge/Si heterojunction. Opt Express 2017; 25:19487-19496. [PMID: 29041142 DOI: 10.1364/oe.25.019487] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 07/31/2017] [Indexed: 06/07/2023]
Abstract
Germanium photodetectors are considered to be mature components in the silicon photonics device library. They are critical for applications in sensing, communications, or optical interconnects. In this work, we report on design, fabrication, and experimental demonstration of an integrated waveguide PIN photodiode architecture that calls upon lateral double Silicon/Germanium/Silicon (Si/Ge/Si) heterojunctions. This photodiode configuration takes advantage of the compatibility with contact process steps of silicon modulators, yielding reduced fabrication complexity for transmitters and offering high-performance optical characteristics, viable for high-speed and efficient operation near 1.55 μm wavelengths. More specifically, we experimentally obtained at a reverse voltage of 1V a dark current lower than 10 nA, a responsivity higher than 1.1 A/W, and a 3 dB opto-electrical cut-off frequency over 50 GHz. The combined benefits of decreased process complexity and high-performance device operation pave the way towards attractive integration strategies to deploy cost-effective photonic transceivers on silicon-on-insulator substrates.
Collapse
|
23
|
Abstract
Using previously recorded spectra of HCl diluted in Ar gas at room temperature for several pressure conditions, we show that the absorptions in between successive P and R transitions are significantly different from those predicted using purely Lorentzian line shapes. Direct theoretical predictions of the spectra are also made using requantized classical molecular dynamics simulations and an input HCl-Ar interaction potential. They provide the time evolution of the dipole auto-correlation function (DAF) whose Fourier-Laplace transform yields the absorption spectrum. These calculations very well reproduce the observed super-Lorentzian behavior in the troughs between the intense lines in the central part of the band and the tendency of absorption to become sub-Lorentzian in the band wings between high J lines. The analysis shows that the former behavior is essentially due to incomplete collisions which govern the DAF at very short times. In addition, the increasing influence of line-mixing when going away from the band center explains the tendency of absorption to become more and more sub-Lorentzian in the wings.
Collapse
Affiliation(s)
- Ha Tran
- Laboratoire de Météorologie Dynamique, IPSL, CNRS, Sorbonne Universités, UPMC University Paris 06, 75252 Paris, France
| | - Gang Li
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - Volker Ebert
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - Jean-Michel Hartmann
- Laboratoire de Météorologie Dynamque, IPSL, CNRS, Ecole Polytechnique, Université Paris-Saclay, 91128 Palaiseau, France
| |
Collapse
|
24
|
von den Driesch N, Stange D, Wirths S, Rainko D, Povstugar I, Savenko A, Breuer U, Geiger R, Sigg H, Ikonic Z, Hartmann JM, Grützmacher D, Mantl S, Buca D. SiGeSn Ternaries for Efficient Group IV Heterostructure Light Emitters. Small 2017; 13:1603321. [PMID: 28160408 DOI: 10.1002/smll.201603321] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 12/21/2016] [Indexed: 06/06/2023]
Abstract
SiGeSn ternaries are grown on Ge-buffered Si wafers incorporating Si or Sn contents of up to 15 at%. The ternaries exhibit layer thicknesses up to 600 nm, while maintaining a high crystalline quality. Tuning of stoichiometry and strain, as shown by means of absorption measurements, allows bandgap engineering in the short-wave infrared range of up to about 2.6 µm. Temperature-dependent photoluminescence experiments indicate ternaries near the indirect-to-direct bandgap transition, proving their potential for ternary-based light emitters in the aforementioned optical range. The ternaries' layer relaxation is also monitored to explore their use as strain-relaxed buffers, since they are of interest not only for light emitting diodes investigated in this paper but also for many other optoelectronic and electronic applications. In particular, the authors have epitaxially grown a GeSn/SiGeSn multiquantum well heterostructure, which employs SiGeSn as barrier material to efficiently confine carriers in GeSn wells. Strong room temperature light emission from fabricated light emitting diodes proves the high potential of this heterostructure approach.
Collapse
Affiliation(s)
- Nils von den Driesch
- Peter Grünberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies (JARA-FIT), Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Daniela Stange
- Peter Grünberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies (JARA-FIT), Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Stephan Wirths
- Peter Grünberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies (JARA-FIT), Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Denis Rainko
- Peter Grünberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies (JARA-FIT), Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Ivan Povstugar
- Central Institute for Engineering, Electronics and Analytics - Analytics, Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Aleksei Savenko
- Central Institute for Engineering, Electronics and Analytics - Analytics, Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Uwe Breuer
- Central Institute for Engineering, Electronics and Analytics - Analytics, Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Richard Geiger
- Laboratory for Micro- and Nanotechnology (LMN), Paul Scherrer Institute, CH-5232, Villigen, Switzerland
| | - Hans Sigg
- Laboratory for Micro- and Nanotechnology (LMN), Paul Scherrer Institute, CH-5232, Villigen, Switzerland
| | - Zoran Ikonic
- Institute of Microwaves and Photonics, School of Electronic and Electrical Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - Jean-Michel Hartmann
- CEA, LETI, MINATEC Campus, F-38054, Grenoble, France
- Univ. Grenoble Alpes, F-38000, Grenoble, France
| | - Detlev Grützmacher
- Peter Grünberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies (JARA-FIT), Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Siegfried Mantl
- Peter Grünberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies (JARA-FIT), Forschungszentrum Juelich, 52425, Juelich, Germany
| | - Dan Buca
- Peter Grünberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies (JARA-FIT), Forschungszentrum Juelich, 52425, Juelich, Germany
| |
Collapse
|
25
|
Schulte-Braucks C, Narimani K, Glass S, von den Driesch N, Hartmann JM, Ikonic Z, Afanas'ev VV, Zhao QT, Mantl S, Buca D. Correlation of Bandgap Reduction with Inversion Response in (Si)GeSn/High-k/Metal Stacks. ACS Appl Mater Interfaces 2017; 9:9102-9109. [PMID: 28221764 DOI: 10.1021/acsami.6b15279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The bandgap tunability of (Si)GeSn group IV semiconductors opens a new era in Si-technology. Depending on the Si/Sn contents, direct and indirect bandgaps in the range of 0.4-0.8 eV can be obtained, offering a broad spectrum of both photonic and low power electronic applications. In this work, we systematically studied capacitance-voltage characteristics of high-k/metal gate stacks formed on GeSn and SiGeSn alloys with Sn-contents ranging from 0 to 14 at. % and Si-contents from 0 to 10 at. % particularly focusing on the minority carrier inversion response. A clear correlation between the Sn-induced shrinkage of the bandgap energy and enhanced minority carrier response was confirmed using temperature and frequency dependent capacitance voltage-measurements, in good agreement with k.p theory predictions and photoluminescence measurements of the analyzed epilayers as reported earlier. The enhanced minority generation rate for higher Sn-contents can be firmly linked to the bandgap reduction in the GeSn epilayer without significant influence of substrate/interface effects. It thus offers a unique possibility to analyze intrinsic defects in (Si)GeSn epilayers. The extracted dominant defect level for minority carrier inversion lies approximately 0.4 eV above the valence band edge in the studied Sn-content range (0-12.5 at. %). This finding is of critical importance since it shows that the presence of Sn by itself does not impair the minority carrier lifetime. Therefore, the continuous improvement of (Si)GeSn material quality should yield longer nonradiative recombination times which are required for the fabrication of efficient light detectors and to obtain room temperature lasing action.
Collapse
Affiliation(s)
- C Schulte-Braucks
- Peter Grünberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH , 52425 Juelich, Germany
| | - K Narimani
- Peter Grünberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH , 52425 Juelich, Germany
| | - S Glass
- Peter Grünberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH , 52425 Juelich, Germany
| | - N von den Driesch
- Peter Grünberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH , 52425 Juelich, Germany
| | - J M Hartmann
- Université Grenoble Alpes , 38000 Grenoble, France
- CEA , LETI, Minatec Campus, 38054 Grenoble, France
| | - Z Ikonic
- Institute of Microwaves and Photonics, Schools of Electronic and Electrical Engineering, University of Leeds , Leeds L2 9JT, United Kingdom
| | - V V Afanas'ev
- Semiconductor Physics Laboratory, KU Leuven , 3001 Leuven, Belgium
| | - Q T Zhao
- Peter Grünberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH , 52425 Juelich, Germany
| | - S Mantl
- Peter Grünberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH , 52425 Juelich, Germany
| | - D Buca
- Peter Grünberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH , 52425 Juelich, Germany
| |
Collapse
|
26
|
Tardif S, Gassenq A, Guilloy K, Pauc N, Osvaldo Dias G, Hartmann JM, Widiez J, Zabel T, Marin E, Sigg H, Faist J, Chelnokov A, Reboud V, Calvo V, Micha JS, Robach O, Rieutord F. Lattice strain and tilt mapping in stressed Ge microstructures using X-ray Laue micro-diffraction and rainbow filtering. J Appl Crystallogr 2016. [DOI: 10.1107/s1600576716010347] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Laue micro-diffraction and simultaneous rainbow-filtered micro-diffraction were used to measure accurately the full strain tensor and the lattice orientation distribution at the sub-micrometre scale in highly strained, suspended Ge micro-devices. A numerical approach to obtain the full strain tensor from the deviatoric strain measurement alone is also demonstrated and used for faster full strain mapping. The measurements were performed in a series of micro-devices under either uniaxial or biaxial stress and an excellent agreement with numerical simulations was found. This shows the superior potential of Laue micro-diffraction for the investigation of highly strained micro-devices.
Collapse
|
27
|
Stange D, von den Driesch N, Rainko D, Schulte-Braucks C, Wirths S, Mussler G, Tiedemann AT, Stoica T, Hartmann JM, Ikonic Z, Mantl S, Grützmacher D, Buca D. Study of GeSn based heterostructures: towards optimized group IV MQW LEDs. Opt Express 2016; 24:1358-1367. [PMID: 26832516 DOI: 10.1364/oe.24.001358] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present results on CVD growth and electro-optical characterization of Ge(0.92)Sn(0.08)/Ge p-i-n heterostructure diodes. The suitability of Ge as barriers for direct bandgap GeSn active layers in different LED geometries, such as double heterostructures and multi quantum wells is discussed based on electroluminescence data. Theoretical calculations by effective mass and 6 band k∙p method reveal low barrier heights for this specific structure. Best configurations offer only a maximum barrier height for electrons of about 40 meV at the Γ point at room temperature (e.g. 300 K), evidently insufficient for proper light emitting devices. An alternative solution using SiGeSn as barrier material is introduced, which provides appropriate band alignment for both electrons and holes resulting in efficient confinement in direct bandgap GeSn wells. Finally, epitaxial growth of such a complete SiGeSn/GeSn/SiGeSn double heterostructure including doping is shown.
Collapse
|
28
|
Carletti L, Sinobad M, Ma P, Yu Y, Allioux D, Orobtchouk R, Brun M, Ortiz S, Labeye P, Hartmann JM, Nicoletti S, Madden S, Luther-Davies B, Moss DJ, Monat C, Grillet C. Mid-infrared nonlinear optical response of Si-Ge waveguides with ultra-short optical pulses. Opt Express 2015; 23:32202-32214. [PMID: 26699010 DOI: 10.1364/oe.23.032202] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We characterize the nonlinear optical response of low loss Si(0.6)Ge(0.4) / Si waveguides in the mid-infrared between 3.3 μm and 4 μm using femtosecond optical pulses. We estimate the three and four-photon absorption coefficients as well as the Kerr nonlinear refractive index from the experimental measurements. The effect of multiphoton absorption on the optical nonlinear Kerr response is evaluated and the nonlinear figure of merit estimated providing some guidelines for designing nonlinear optical devices in the mid-IR. Finally, we compare the impact of free-carrier absorption at mid-infrared wavelengths versus near-infrared wavelengths for these ultra-short pulses.
Collapse
|
29
|
Barritault P, Brun M, Labeye P, Hartmann JM, Boulila F, Carras M, Nicoletti S. Design, fabrication and characterization of an AWG at 4.5 µm. Opt Express 2015; 23:26168-26181. [PMID: 26480131 DOI: 10.1364/oe.23.026168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this paper, we present the design, the fabrication and the characterization of an Arrayed Waveguide Grating (AWG) based on a SiGe graded index waveguide platform, operating at 4.5 µm. These devices were specifically designed to work together with an array of Distributed Feedback Bragg Quantum Cascade Lasers (DFB-QCL) emitting at different wavelengths. The AWG enables to combine the different light sources into a single output and the design adopted allows to maximize transmission over the entire spectral range defined by the array of DFB-QCLs.
Collapse
|
30
|
Khodorkovsky Y, Steinitz U, Hartmann JM, Averbukh IS. Collisional dynamics in a gas of molecular super-rotors. Nat Commun 2015; 6:7791. [PMID: 26160223 PMCID: PMC4510972 DOI: 10.1038/ncomms8791] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 06/10/2015] [Indexed: 11/25/2022] Open
Abstract
Recently, femtosecond laser techniques have been developed that are capable of bringing gas molecules to extremely fast rotation in a very short time, while keeping their translational motion relatively slow. Here we study collisional equilibration dynamics of this new state of molecular gases. We show that the route to equilibrium starts with a metastable 'gyroscopic stage' in the course of which the molecules maintain their fast rotation and orientation of the angular momentum through many collisions. The inhibited rotational-translational relaxation is characterized by a persistent anisotropy in the molecular angular distribution, and is manifested in the optical birefringence and anisotropic diffusion in the gas. After a certain induction time, the 'gyroscopic stage' is abruptly terminated by an explosive rotational-translational energy exchange, leading the gas towards the final equilibrium. We illustrate our conclusions by direct molecular dynamics simulation of several gases of linear molecules.
Collapse
Affiliation(s)
- Yuri Khodorkovsky
- Department of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Uri Steinitz
- Department of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jean-Michel Hartmann
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA) CNRS (UMR 7583), Université Paris Est Créteil, Université Paris Diderot, Institut Pierre-Simon Laplace, 94010 Créteil, France
| | - Ilya Sh. Averbukh
- Department of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
| |
Collapse
|
31
|
Estivill R, Grenier A, Duguay S, Vurpillot F, Terlier T, Barnes JP, Hartmann JM, Blavette D. Quantitative analysis of Si/SiGeC superlattices using atom probe tomography. Ultramicroscopy 2015; 159 Pt 2:223-31. [PMID: 25814020 DOI: 10.1016/j.ultramic.2015.03.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 03/05/2015] [Accepted: 03/13/2015] [Indexed: 11/29/2022]
Abstract
SiGe and its alloys are used as key materials in innovative electronic devices. The analysis of these materials together with the localisation of dopants and impurities on a very fine scale is of crucial importance for better understanding their electronic properties. The quantification of carbon and germanium in an as-grown Si/SiGeC superlattice has been investigated using Atom Probe Tomography as a function of analysis conditions and sample anneal temperature. The mass spectrum is heavily influenced by the analysis conditions and chemical identification is needed. It was found that quantitative results are obtained using a intermediate electric field. The evaporation of carbon ions shows a strong spatial and temporal correlation. A series of annealed samples have been analysed, presenting an inhomogeneous carbon distribution, appearing in the shape of small clusters. These findings confirm previous results and give a better understanding of the processes occurring in these technologically important materials.
Collapse
Affiliation(s)
- Robert Estivill
- Univ. Grenoble Alpes, 38000 Grenoble, France; CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble, France; STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex, France; Groupe de Physique des Matériaux - GPM UMR CNRS 6634, Université de Rouen, France.
| | - Adeline Grenier
- Univ. Grenoble Alpes, 38000 Grenoble, France; CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble, France
| | - Sébastien Duguay
- Groupe de Physique des Matériaux - GPM UMR CNRS 6634, Université de Rouen, France
| | - François Vurpillot
- Groupe de Physique des Matériaux - GPM UMR CNRS 6634, Université de Rouen, France
| | - Tanguy Terlier
- Univ. Grenoble Alpes, 38000 Grenoble, France; CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble, France; STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex, France
| | - Jean-Paul Barnes
- Univ. Grenoble Alpes, 38000 Grenoble, France; CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble, France; STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex, France
| | - Jean-Michel Hartmann
- Univ. Grenoble Alpes, 38000 Grenoble, France; CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble, France; STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex, France
| | - Didier Blavette
- Groupe de Physique des Matériaux - GPM UMR CNRS 6634, Université de Rouen, France
| |
Collapse
|
32
|
Estivill R, Grenier A, Duguay S, Vurpillot F, Terlier T, Barnes JP, Hartmann JM, Blavette D. Quantitative investigation of SiGeC layers using atom probe tomography. Ultramicroscopy 2015; 150:23-29. [DOI: 10.1016/j.ultramic.2014.11.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 11/07/2014] [Accepted: 11/10/2014] [Indexed: 11/25/2022]
|
33
|
Wirths S, Stange D, Pampillón MA, Tiedemann AT, Mussler G, Fox A, Breuer U, Baert B, San Andrés E, Nguyen ND, Hartmann JM, Ikonic Z, Mantl S, Buca D. High-k gate stacks on low bandgap tensile strained Ge and GeSn alloys for field-effect transistors. ACS Appl Mater Interfaces 2015; 7:62-67. [PMID: 25531887 DOI: 10.1021/am5075248] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present the epitaxial growth of Ge and Ge0.94Sn0.06 layers with 1.4% and 0.4% tensile strain, respectively, by reduced pressure chemical vapor deposition on relaxed GeSn buffers and the formation of high-k/metal gate stacks thereon. Annealing experiments reveal that process temperatures are limited to 350 °C to avoid Sn diffusion. Particular emphasis is placed on the electrical characterization of various high-k dielectrics, as 5 nm Al2O3, 5 nm HfO2, or 1 nmAl2O3/4 nm HfO2, on strained Ge and strained Ge0.94Sn0.06. Experimental capacitance-voltage characteristics are presented and the effect of the small bandgap, like strong response of minority carriers at applied field, are discussed via simulations.
Collapse
Affiliation(s)
- Stephan Wirths
- Peter Grünberg Institute (PGI 9) and JARA-FIT , Forschungszentrum Jülich, 52425 Jülich, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Tennyson J, Bernath PF, Campargue A, Császár AG, Daumont L, Gamache RR, Hodges JT, Lisak D, Naumenko OV, Rothman LS, Tran H, Zobov NF, Buldyreva J, Boone CD, De Vizia MD, Gianfrani L, Hartmann JM, McPheat R, Weidmann D, Murray J, Ngo NH, Polyansky OL. Recommended isolated-line profile for representing high-resolution spectroscopic transitions (IUPAC Technical Report). PURE APPL CHEM 2014. [DOI: 10.1515/pac-2014-0208] [Citation(s) in RCA: 196] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The report of an IUPAC Task Group, formed in 2011 on “Intensities and line shapes in high-resolution spectra of water isotopologues from experiment and theory” (Project No. 2011-022-2-100), on line profiles of isolated high-resolution rotational-vibrational transitions perturbed by neutral gas-phase molecules is presented. The well-documented inadequacies of the Voigt profile (VP), used almost universally by databases and radiative-transfer codes, to represent pressure effects and Doppler broadening in isolated vibrational-rotational and pure rotational transitions of the water molecule have resulted in the development of a variety of alternative line-profile models. These models capture more of the physics of the influence of pressure on line shapes but, in general, at the price of greater complexity. The Task Group recommends that the partially Correlated quadratic-Speed-Dependent Hard-Collision profile (pCqSD-HCP) should be adopted as the appropriate model for high-resolution spectroscopy. For simplicity this should be called the Hartmann–Tran profile (HTP). The HTP is sophisticated enough to capture the various collisional contributions to the isolated line shape, can be computed in a straightforward and rapid manner, and reduces to simpler profiles, including the Voigt profile, under certain simplifying assumptions.
Collapse
|
35
|
Morales SB, Pangui E, Landsheere X, Tran H, Hartmann JM. Variable-length cell for studies of gas spectra with extremely short optical paths. Appl Opt 2014; 53:4117-4122. [PMID: 25089968 DOI: 10.1364/ao.53.004117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 05/21/2014] [Indexed: 06/03/2023]
Abstract
We present a cell for studies of light transmission through very strongly absorbing gases. It uses a fixed window and a mirror, parallel to the latter and attached to a micrometric linear motion feedthrough monitoring mirror-window distances from 0 to a couple of centimeters. This device is tested by recording CO2 gas spectra near 4.3 μm using a Fourier transform spectrometer. Their analysis shows that optical-path lengths between 20 and 2000 μm have been obtained. This now enables spectroscopic measurements of self-broadening coefficients of O16C12O16 lines in the ν3 band, for instance, and opens perspectives for optical soundings of thin films of porous materials.
Collapse
|
36
|
Abstract
We present (far-infrared) Collision Induced Absorption (CIA) spectra calculations for pure gaseous N2 made for the first time, from first-principles. They were carried out using classical molecular dynamics simulations based on ab initio predictions of both the intermolecular potential and the induced-dipole moment. These calculations reproduce satisfactory well the experimental values (intensity and band profile) with agreement within 3% at 149 K. With respect to results obtained with only the long range (asymptotic) dipole moment (DM), including the short range overlap contribution improves the band intensity and profile at 149 K, but it deteriorates them at 296 K. The results show that the relative contribution of the short range DM to the band intensity is typically around 10%. We have also examined the sensitivity of the calculated CIA to the intermolecular potential anisotropy, providing a test of the so-called isotropic approximation used up to now in all N2 CIA calculations. As all these effects interfere simultaneously with quantitatively similar influences (around 10%), it is rather difficult to assert which one could explain remaining deviations with the experimental results. Furthermore, the rather large uncertainties and sometimes inconsistencies of the available measurements forbid any definitive conclusion, stressing the need for new experiments.
Collapse
Affiliation(s)
| | - Jean-Michel Hartmann
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil, Université Paris Diderot, Institut Pierre-Simon Laplace, 94010 Créteil cedex, France
| |
Collapse
|
37
|
Brun M, Labeye P, Grand G, Hartmann JM, Boulila F, Carras M, Nicoletti S. Low loss SiGe graded index waveguides for mid-IR applications. Opt Express 2014; 22:508-518. [PMID: 24515011 DOI: 10.1364/oe.22.000508] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the last few years Mid InfraRed (MIR) photonics has received renewed interest for a variety of commercial, scientific and military applications. This paper reports the design, the fabrication and the characterization of SiGe/Si based graded index waveguides and photonics integrated devices. The thickness and the Ge concentration of the core layer were optimized to cover the full [3 - 8 µm] band. The developed SiGe/Si stack has been used to fabricate straight waveguides and basic optical functions such as Y-junction, crossings and couplers. Straight waveguides showed losses as low as 1 dB/cm at λ = 4.5 µm and 2 dB/cm at 7.4 µm. Likewise straight waveguides, basic functions exhibit nearly theoretical behavior with losses compatible with the implementation of more complex functions in integrated photonics circuits. To the best of our knowledge, the performances of those Mid-IR waveguides significantly exceed the state of the art, confirming the feasibility of using graded SiGe/Si devices in a wide range of wavelengths. These results represent a capital breakthrough to develop a photonic platform working in the Mid-IR range.
Collapse
|
38
|
Barritault P, Brun M, Labeye P, Lartigue O, Hartmann JM, Nicoletti S. Mlines characterization of the refractive index profile of SiGe gradient waveguides at 2.15 µm. Opt Express 2013; 21:11506-11515. [PMID: 23670007 DOI: 10.1364/oe.21.011506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
SiGe alloys present a large Infra-Red transparency window and a full compatibility with the standard Complementary Metal Oxide Semiconductor processing making them suitable for applications in integrated optics. In this paper we report on Mlines characterization of Si(1-x)Ge(x) graded index waveguides at 2.15 µm. First, a law giving the refractive index of a Si(1-x)Ge(x) alloy as a function of the Ge content x: n = 1.342x(2) + 0.295x + 3.451, has been experimentally established in the 0 < x < 0.4 range. Then, we have demonstrated that our methodology based on Mlines measurements can be used as short-loop non-destructive technique to provide feedback for sample growth.
Collapse
Affiliation(s)
- Pierre Barritault
- CEA-LETI, MINATEC Campus, 17 Rue des Martyrs - 38054 GRENOBLE Cedex 9, France.
| | | | | | | | | | | |
Collapse
|
39
|
Chang YC, Paeder V, Hvozdara L, Hartmann JM, Herzig HP. Low-loss germanium strip waveguides on silicon for the mid-infrared. Opt Lett 2012; 37:2883-5. [PMID: 22825166 DOI: 10.1364/ol.37.002883] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Mid-infrared photonics in silicon needs low-loss integrated waveguides. While monocrystalline germanium waveguides on silicon have been proposed, experimental realization has not been reported. Here we demonstrate a germanium strip waveguide on a silicon substrate. It is designed for single mode transmission of light in transverse magnetic (TM) polarization generated from quantum cascade lasers at a wavelength of 5.8 μm. The propagation losses were measured with the Fabry-Perot resonance method. The lowest achieved propagation loss is 2.5 dB/cm, while the bending loss is measured to be 0.12 dB for a 90° bend with a radius of 115 μm.
Collapse
Affiliation(s)
- Yu-Chi Chang
- Optics & Photonics Technology Laboratory, Ecole Polytechnique Fédérale de Lausanne, Breguet 2, 2000 Neuchâtel, Switzerland. yu‑
| | | | | | | | | |
Collapse
|
40
|
Ngo NH, Tran H, Gamache RR, Hartmann JM. Pressure effects on water vapour lines: beyond the Voigt profile. Philos Trans A Math Phys Eng Sci 2012; 370:2495-2508. [PMID: 22547229 DOI: 10.1098/rsta.2011.0272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A short overview of recent results on the effects of pressure (collisions) regarding the shape of isolated infrared lines of water vapour is presented. The first part of this study considers the basic collisional quantities, which are the pressure-broadening and -shifting coefficients, central parameters of the Lorentzian (and Voigt) profile and thus of any sophisticated line-shape model. Through comparisons of measured values with semi-classical calculations, the influences of the molecular states (both rotational and vibrational) involved and of the temperature are analysed. This shows the relatively unusual behaviour of H(2)O broadening, with evidence of a significant vibrational dependence and the fact that the broadening coefficient (in cm(-1) atm(-1)) of some lines increases with temperature. In the second part of this study, line shapes beyond the Voigt model are considered, thus now taking 'velocity effects' into account. These include both the influence of collisionally induced velocity changes that lead to the so-called Dicke narrowing and the influence of the dependence of collisional parameters on the speed of the radiating molecule. Experimental evidence of deviations from the Voigt shape is presented and analysed. The interest of classical molecular dynamics simulations, to model velocity changes, together with semi-classical calculations of the speed-dependent collisional parameters for line-shape predictions from 'first principles', are discussed.
Collapse
Affiliation(s)
- N H Ngo
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), CNRS (UMR 7583), Institut Pierre-Simon Laplace, Université Paris Diderot, Université Paris Est Créteil, 94010 Créteil Cedex, France
| | | | | | | |
Collapse
|
41
|
Letertre F, Deguet C, Richtarch C, Faure B, Hartmann JM, Chieu F, Beaumont A, Dechamp J, Morales C, Allibert F, Perreau P, Pocas S, Personnic S, Lagahe-Blanchard C, Ghyselen B, Vaillant YML, Jalaguier, Kernevez N, Mazure C. Germanium-On-Insulator (GeOI) structure realized by the Smart Cut™ technology. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-809-b4.4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTFirst results on formation of thin film GeOI structures by the Smart Cut™ technology are presented in this paper. Thin single crystal layers of Ge have been successfully transferred, via oxide bonding layer, onto standard Si substrates with diameters ranging from 100 to 200 mm. Compared to SOI manufacturing, the development of GeOI requires adaptation to the available germanium material, since the starting material can be either bulk Ge or an epitaxial layer. Some results will be presented for GeOI formation according to the different technological options. Germanium splitting kinetics will be discussed and compared to already published results. To show good quality of the GeOI structures, detailed characterization has been done by TEM cross sections for defect densities, interfaces abruptness and layers homogeneities evaluation. AFM was used for surface roughness measurements. These results help define procedures that are required to achieve large diameter high quality GeOI structures.
Collapse
|
42
|
Py M, Barnes JP, Lafond D, Hartmann JM. Quantitative profiling of SiGe/Si superlattices by time-of-flight secondary ion mass spectrometry: the advantages of the extended Full Spectrum protocol. Rapid Commun Mass Spectrom 2011; 25:629-638. [PMID: 21290450 DOI: 10.1002/rcm.4904] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The abundance of work on SiGe-based devices demonstrates the importance of the compositional characterization of such materials. However, Secondary Ion Mass Spectrometry (SIMS) characterization of SiGe layers often suffers from matrix effects due to the non-linear variation of ionization yields with Ge content. Several solutions have been proposed in order to overcome this problem, each having its own limitations such as a restricted germanium concentration range, or a weak sensitivity to dopants or impurities. Here, we studied the improvements brought by an alternative protocol: the extended Full Spectrum protocol, which states proportionality between the composition of the secondary ion beam and that of the actual material. Previous studies on this protocol showed that it was extremely precise and reproducible for Ge quantification in a permanent regime, because of minimized matrix effects. In this study we thus investigated its accuracy for the simultaneous quantitative depth profiling of both matrix elements (Si, Ge) and impurities (B, C or P) in strained SiGe/Si superlattices by comparing results with those from more classic protocols. The profiles provided by the extended Full Spectrum protocol were found to be accurate, and to exhibit better properties than classic protocols in terms of signal/noise ratio and signal stability, along with a slight enhancement in depth resolution.
Collapse
Affiliation(s)
- M Py
- CEA-Leti, MINATEC Campus, Grenoble, France.
| | | | | | | |
Collapse
|
43
|
|
44
|
Abstract
The present work is an intercomparison of experimental results on the pressure broadening and pressure shifting of water vapor absorption lines. The work focuses on application to the Earth's atmosphere; hence measurements of nitrogen, oxygen, air, and H2O as the buffer, or perturbing gas, were considered. The literature was searched and over 100 papers found. The data, measured half-widths, their temperature dependence, and the line shifts, were taken and databases created for each perturbing gas. The databases were reordered, grouping data for rovibrational transitions, and intercomparisons of the measurements made. Trends in the data, relationships between the data sets, and dependences on temperature and quantum numbers were investigated. The data were averaged and an estimated uncertainty determined. The averaged data sets are evaluated with respect to the need of the spectroscopic and remote sensing communities. Based on these studies, recommendations for new measurements are made.Key words: water vapor, half-widths, line shifts, temperature dependence of half-width.
Collapse
|
45
|
Hadded S, Thibault F, Flaud PM, Aroui H, Hartmann JM. Experimental and theoretical study of line mixing in NH3 spectra. II. Effect of the perturber in infrared parallel bands. J Chem Phys 2004; 120:217-23. [PMID: 15267280 DOI: 10.1063/1.1630306] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In a previous paper [J. Chem. Phys. 116, 7544 (2002) (Paper I)] a model, based on the energy corrected sudden approximation, was proposed for the construction of the line-mixing relaxation matrix. It was successfully tested by comparisons with measured infrared spectra of ammonia-helium mixtures. The present paper extends this preliminary study by considering mixtures of NH3 with H2 and Ar. Measurements have been made at room temperature in the regions of the nu2 and nu1 bands for pressures up to several hundred atmospheres. As in Paper I, the relaxation operator is constructed, within the impact approximation, using the ECS approximation. The data required are dynamical factors (which can be predicted from the NH3-X potential energy surface) and a scaling length (adjusted using line broadening data). Comparisons between measured and calculated absorptions demonstrate the quality of the model which satisfactory corrects for the large deviations with respect to the purely Lorentzian behavior. Line-mixing effects for NH3-Ar and NH3-H2 are qualitatively similar to those observed for NH3-He but quantitative differences exist, particularly when intra- and interbranch couplings are considered. Finally, the proposed model leads to very satisfactory results in the wings of both the purely rotational and nu2 bands of NH3 diluted in H2, opening promising perspectives for the remote sensing study of planetary atmospheres.
Collapse
Affiliation(s)
- S Hadded
- Laboratoire de PhotoPhysique Moléculaire, UPR 3361 du CNRS, Université Paris-Sud (bat. 350), 91495 Orsay, France
| | | | | | | | | |
Collapse
|
46
|
Boissoles J, Thibault F, Boulet C, Bouanich JP, Hartmann JM. Spectral Lineshape Parameters Revisited for HF in a Bath of Argon. J Mol Spectrosc 1999; 198:257-262. [PMID: 10547308 DOI: 10.1006/jmsp.1999.7908] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Previous measurements of asymmetries of the profiles of argon-broadened HF lines at moderate perturber densities (pressures higher than 10 atm) have been confirmed and extended by high-resolution Fourier transform spectroscopy. In some cases, the asymmetries observed here are of opposite sign when compared to the results obtained at much lower densities (pressures lower than 1 atm). By comparing all the available experiments, the competition between the various mechanisms leading to asymmetries has been analyzed as function of the perturber pressure and the vibrational transitions considered. Copyright 1999 Academic Press.
Collapse
Affiliation(s)
- J Boissoles
- UMR 6627 du CNRS, Université de Rennes I, Campus de Beaulieu, Rennes Cedex, 35042, France
| | | | | | | | | |
Collapse
|
47
|
Grigoriev IM, Boissoles J, Calil B, Boulet C, Hartmann JM, Bruet X, Dubernet ML. Spectral Lineshape Parameters Revisited for HF in a Bath of Argon. J Mol Spectrosc 1999; 198:249-256. [PMID: 10547307 DOI: 10.1006/jmsp.1999.7903] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The test of an interaction potential for HF-argon recently determined from the spectroscopy of the Van der Waals complex requires accurate experimental widths and shifts cross sections. Since inconsistencies existed between previous measurements, collisional lineshapes were studied at T = 296 K by high-resolution Fourier transform spectroscopy for the 0-0, 0-1, and 0-2 bands. The accurate close-coupling molecular scattering calculations of Green and Hutson (1994. J. Chem. Phys. 100, 891) were extended to a complementary set of kinetic energies in order to check the thermal averaging procedure. Agreement between measured and computed room temperature cross sections is excellent for the three vibrational bands. This confirms the accuracy of the HF-argon surface and particularly its dependence on the HF vibrational level, which is sensitively probed both by the widths and by the shifts cross sections at high j(i) values. Copyright 1999 Academic Press.
Collapse
Affiliation(s)
- IM Grigoriev
- U.M.R. 6627 du C.N.R.S., Université de Rennes I, Campus de Beaulieu, Rennes Cedex, 35042, France
| | | | | | | | | | | | | |
Collapse
|
48
|
Kochel JM, Hartmann JM, Camy-Peyret C, Rodrigues R, Payan S. Influence of line mixing on absorption by CO2Q branches in atmospheric balloon-borne spectra near 13 μm. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jd00405] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
49
|
Hartmann JM, Houlihan BT, Thompson LD, Chan C, Baldwin RA, Buse EL. The effect of sampling error and measurement error and its correlation on the estimation of multi-locus fixed-bin VNTR RFLP genotype probabilities. J Forensic Sci 1997; 42:241-5. [PMID: 9068182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Bootstrapping was used to examine the effect of sampling error and measurement error and its correlation on fixed-bin genotype probabilities. Bootstrap confidence intervals (Cls) were made relative to the point estimate using the log of the inverse of the probabilities. From databases of 200-250 genotypes, sampling error alone yielded median relative 95% CIs of from one order of magnitude out of five for one locus to one out of ten for four loci. Measurement error of the test genotype fragments increased the latter to about one order of magnitude out of eight. Database measurement error and its correlation had only a slight effect on multi-locus probability uncertainty. Together, these uncertainties are several orders of magnitude greater than error due to population substructuring of a race by its major component ethnic groups.
Collapse
Affiliation(s)
- J M Hartmann
- Forensic Science Services, Orange County Sheriff-Coroner Department, Santa Ana, CA, USA
| | | | | | | | | | | |
Collapse
|
50
|
Hartmann JM, Houlihan BT, Keister RS, Buse EL. The effect of ethnic and racial population substructuring on the estimation of multi-locus fixed-bin VNTR RFLP genotype probabilities. J Forensic Sci 1997; 42:232-40. [PMID: 9068181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Four East Asian ethnic and four racial VNTR RFLP Southern California databases were used to determine the impact of population substructure on fixed-bin genotype probability estimates. Two calculations were used for population-level probabilities: Stratified sampling, which takes substructuring into account, and pooling, which ignores it. Using 1000 four-locus genotypes, the relative difference between probabilities calculated with the stratified and the pooled methods did not exceed one order of magnitude out of about 11 orders of magnitude for East-Asian racial genotypes. Pooled estimates differed from cognate ethnic values by less than one order of magnitude out of about six. These findings suggest substructuring of races by major ethnic groups does not lead to large errors. Racial genotype probability variances were on average about twice the ethnic variances. Multi-racial total population probabilities calculated by the pooled and stratified methods differed by less than one order of magnitude out of five.
Collapse
Affiliation(s)
- J M Hartmann
- Forensic Science Services, Orange County Sheriff-Coroner Department, Santa Ana, CA 92703, USA
| | | | | | | |
Collapse
|