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Chabanais F, Di Russo E, Karg A, Eickhoff M, Lefebvre W, Rigutti L. Behavior of the ε-Ga 2O 3:Sn Evaporation During Laser-Assisted Atom Probe Tomography. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2021; 27:687-695. [PMID: 34169814 DOI: 10.1017/s1431927621000544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The measurement of the composition of ε-Ga2O3 and the quantification of Sn doping in ε-Ga2O3:Sn by laser-assisted atom probe tomography (APT) may be inaccurate depending on the experimental conditions. Both the role of the laser energy and surface electric field were investigated, and the results clearly indicate that deviations from stoichiometry are observed changing the electric field conditions during APT. The measured atomic fraction of Ga can change from 0.45 at low field to 0.38 at high field, to be compared with the expected 0.4. This was interpreted in terms of preferential evaporation of Ga at high field and deficit of O at low field, which was caused by the formation of neutrals. The quantification of Sn-doping is accurate at low-field conditions, with an overestimation of the detected Sn-metallic fraction at high field. This suggests that Sn has a higher evaporation field compared to Ga. Finally, multiple detection events were in-depth studied, revealing that three dissociation reactions occur during APT: GaO2+ → Ga+ + O+; Ga2O22+ → Ga+ + GaO2+; Ga3O22+ → Ga+ + Ga2O2+. Nevertheless, only 2% of the detected events are related to such dissociation reactions, too small a fraction to fully explain the observed deviation from the stoichiometric composition in ε-Ga2O3.
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Affiliation(s)
- Florian Chabanais
- UNIROUEN, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000Rouen, France
| | - Enrico Di Russo
- UNIROUEN, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000Rouen, France
| | - Alexander Karg
- Institute of Solid State Physics, University of Bremen, Bremen, Germany
| | - Martin Eickhoff
- Institute of Solid State Physics, University of Bremen, Bremen, Germany
| | - Williams Lefebvre
- UNIROUEN, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000Rouen, France
| | - Lorenzo Rigutti
- UNIROUEN, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000Rouen, France
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Di Russo E, Blum I, Rivalta I, Houard J, Da Costa G, Vurpillot F, Blavette D, Rigutti L. Detecting Dissociation Dynamics of Phosphorus Molecular Ions by Atom Probe Tomography. J Phys Chem A 2020; 124:10977-10988. [PMID: 33348984 DOI: 10.1021/acs.jpca.0c09259] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dissociation processes involving phosphorus cations were investigated during laser-assisted atom probe tomography of crystalline indium phosphide (InP). This technique not only allows the formation of medium-sized phosphorus cations by means of femtosecond laser pulses under ultrahigh vacuum and high electric field conditions but also allows one to study the time-resolved dissociation dynamics. Data reveal the formation of cations up to P232+ and their subsequent dissociation into two smaller Pk+ cations (k > 2). The use of a time- and position-sensitive detector combined with numerical calculations provided information related to the molecule orientation, decay time, and kinetic energy release during dissociation phenomena. Results suggest that the dissociation processes are most likely due to the emission of Pk2+ cations in excited states and their subsequent decay in low field regions during their flight toward the detector. This study provides operative guidelines to obtain information on dissociation processes using a tomographic atom probe as a reaction microscope and indicates the current capabilities and limitations of such an approach.
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Affiliation(s)
- E Di Russo
- UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000 Rouen, France
| | - I Blum
- UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000 Rouen, France
| | - I Rivalta
- Dipartimento di Chimica Industriale "Toso Montanari", ALMA MATER STUDIORUM, Università di Bologna, Viale del Risorgimento 4, 40126 Bologna, Italia.,Univ Lyon, Ens de Lyon, CNRS UMR 5182, Université Claude Bernard Lyon 1, Laboratoire de Chimie, F69342 Lyon, France
| | - J Houard
- UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000 Rouen, France
| | - G Da Costa
- UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000 Rouen, France
| | - F Vurpillot
- UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000 Rouen, France
| | - D Blavette
- UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000 Rouen, France
| | - L Rigutti
- UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, Normandie Université, 76000 Rouen, France
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Di Russo E, Mavel A, Fan Arcara V, Damilano B, Dimkou I, Vézian S, Grenier A, Veillerot M, Rochat N, Feuillet G, Bonef B, Rigutti L, Duboz JY, Monroy E, Cooper D. Multi-microscopy nanoscale characterization of the doping profile in a hybrid Mg/Ge-doped tunnel junction. NANOTECHNOLOGY 2020; 31:465706. [PMID: 32498042 DOI: 10.1088/1361-6528/ab996c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A multi-microscopy investigation of a GaN tunnel junction (TJ) grown on an InGaN-based light emitting diode (LED) has been performed. The TJ consists of a heavily Ge-doped n-type GaN layer grown by ammonia-based molecular-beam epitaxy on a heavily Mg-doped p-type GaN thin layer, grown by metalorganic vapor phase epitaxy. A correlation of atom probe tomography, electron holography and secondary ion mass spectrometry has been performed in order to investigate the nm-scale distribution of both Mg and Ge at the TJ. Experimental results reveal that Mg segregates at the TJ interface, and diffuses into the Ge-doped layer. As a result, the dopant concentration and distribution differ significantly from the nominal values. Despite this, electron holography reveals a TJ depletion width of ∼7 nm, in agreement with band diagram simulations using the experimentally determined dopant distribution.
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Affiliation(s)
- E Di Russo
- Univ. Grenoble Alpes, CEA, LETI, Grenoble F-38000, France
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Hu R, Xue J, Wu X, Zhang Y, Zhu H, Sha G. Atom Probe Tomography Characterization of Dopant Distributions in Si FinFET: Challenges and Solutions. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2020; 26:36-45. [PMID: 31753061 DOI: 10.1017/s1431927619015137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Atom probe tomography (APT) has emerged as an important tool in characterizing three-dimensional semiconductor devices. However, the complex structure and hybrid nature of a semiconductor device can pose serious challenges to the accurate measurement of dopants. In particular, local magnification and trajectory aberration observed when analyzing hybrid materials with different evaporation fields can cause severe distortions in reconstructed geometry and uncertainty in local chemistry measurement. To address these challenges, this study systematically investigates the effect of APT sampling directions on the measurement of n-type dopants P and As in an Si fin field-effect transistor (FinFET). We demonstrate that the APT samples made with their Z-axis perpendicular to the center axis of the fin are effective to minimize the negative effects that result from evaporation field differences between the Si fin and SiO2 on reconstruction and achieve improved measurement of dopant distributions. In addition, new insights have been gained regarding the distribution of ion-implanted P and As in the Si FinFET.
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Affiliation(s)
- Rong Hu
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu210094, China
| | - Jing Xue
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu210094, China
| | - Xingping Wu
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu210094, China
| | - Yanbo Zhang
- Institute of Microelectronics of Chinese Academy of Sciences, Beijing100029, China
| | - Huilong Zhu
- Institute of Microelectronics of Chinese Academy of Sciences, Beijing100029, China
| | - Gang Sha
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu210094, China
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Amichi L, Mouton I, Boureau V, Di Russo E, Vennéguès P, De Mierry P, Grenier A, Jouneau PH, Bougerol C, Cooper D. Correlative investigation of Mg doping in GaN layers grown at different temperatures by atom probe tomography and off-axis electron holography. NANOTECHNOLOGY 2020; 31:045702. [PMID: 31577995 DOI: 10.1088/1361-6528/ab4a46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Correlation between off-axis electron holography and atom probe tomography (APT) provides morphological, chemical and electrical information about Mg doping (p-type) in gallium nitride (GaN) layers that have been grown at different temperatures at a nanometric scale. APT allows access to the three-dimensional distribution of atoms and their chemical nature. In particular, this technique allows visualisation of the Mg-rich clusters observed in p-doped GaN layers grown by metal-organic chemical vapour deposition. As the layer growth temperature increases, the cluster density decreases but their size indicted by the number of atoms increases. Moreover, APT reveals that threading dislocations are decorated with Mg atoms. Off-axis electron holography provides complementary information about the electrical activity of the Mg doping. As only a small fraction of dopant atoms are ionised at room temperature, this fraction is increased by annealing the specimen to 400 °C in situ in a transmission electron microscope (TEM). A strong reduction of the dopant electrical activity is observed for increases in the layer growth temperature. The correlation of APT with TEM-based techniques was shown to be a unique approach in order to investigate how the growth temperature affects both the chemical distribution and electrical activity of Mg dopant atoms.
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Affiliation(s)
- Lynda Amichi
- Univ. Grenoble Alpes, CEA, INAC, F-38000 Grenoble, France
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Schmidt JE, Peng L, Poplawsky JD, Weckhuysen BM. Nanoskalige chemische Bildgebung von Zeolithen durch Atomsondentomographie. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201712952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Joel E. Schmidt
- Debye Institute for Nanomaterials ScienceUtrecht University Universiteitsweg 99 3584 CG Utrecht Niederlande
| | - Linqing Peng
- Grinnell College 1115 8th Ave Grinnell, IA 50112 USA
| | - Jonathan D. Poplawsky
- Center for Nanophase Materials SciencesOak Ridge National Laboratory Oak Ridge TN 37831-6064 USA
| | - Bert M. Weckhuysen
- Debye Institute for Nanomaterials ScienceUtrecht University Universiteitsweg 99 3584 CG Utrecht Niederlande
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Schmidt JE, Peng L, Poplawsky JD, Weckhuysen BM. Nanoscale Chemical Imaging of Zeolites Using Atom Probe Tomography. Angew Chem Int Ed Engl 2018; 57:10422-10435. [PMID: 29718553 PMCID: PMC6519151 DOI: 10.1002/anie.201712952] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Indexed: 11/11/2022]
Abstract
Understanding structure-composition-property relationships in zeolite-based materials is critical to engineering improved solid catalysts. However, this can be difficult to realize as even single zeolite crystals can exhibit heterogeneities spanning several orders of magnitude, with consequences for, for example, reactivity, diffusion as well as stability. Great progress has been made in characterizing these porous solids using tomographic techniques, though each method has an ultimate spatial resolution limitation. Atom probe tomography (APT) is the only technique so far capable of producing 3D compositional reconstructions with sub-nanometer-scale resolution, and has only recently been applied to zeolite-based catalysts. Herein, we discuss the use of APT to study zeolites, including the critical aspects of sample preparation, data collection, assignment of mass spectral peaks including the predominant CO peak, the limitations of spatial resolution for the recovery of crystallographic information, and proper data analysis. All sections are illustrated with examples from recent literature, as well as previously unpublished data and analyses to demonstrate practical strategies to overcome potential pitfalls in applying APT to zeolites, thereby highlighting new insights gained from the APT method.
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Affiliation(s)
- Joel E Schmidt
- Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, The Netherlands
| | - Linqing Peng
- Grinnell College, 1115 8th Ave, Grinnell, IA, 50112, USA
| | - Jonathan D Poplawsky
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6064, USA
| | - Bert M Weckhuysen
- Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, The Netherlands
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Compositional accuracy of atom probe tomography measurements in GaN: Impact of experimental parameters and multiple evaporation events. Ultramicroscopy 2018; 187:126-134. [PMID: 29454890 DOI: 10.1016/j.ultramic.2018.02.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/31/2018] [Accepted: 02/03/2018] [Indexed: 11/23/2022]
Abstract
A systematic study of the biases occurring in the measurement of the composition of GaN by Atom Probe Tomography was carried out, in which the role of surface electric field and laser pulse intensity has been investigated. Our data confirm that the electric field is the main factor influencing the measured composition, which exhibits a deficiency of N at low field and a deficiency of Ga at high field. The deficiency of Ga at high field is interpreted in terms of preferential evaporation of Ga. The detailed analysis of multiple evaporation events reveals that the measured composition is not affected by pile-up phenomena occurring in detection system. The analysis of correlation histograms yields the signature of the production of neutral N2 due to the dissociation of GaN32+ ions. However, the amount of N2 neutral molecules that can be detected cannot account for the N deficiency found at low field. Therefore, we propose that further mechanisms of neutral N evaporation could be represented by dissociation reactions such as GaN+→ Ga++ N and GaN2+→ Ga2++ N.
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Di Russo E, Blum I, Houard J, Da Costa G, Blavette D, Rigutti L. Field-Dependent Measurement of GaAs Composition by Atom Probe Tomography. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2017; 23:1067-1075. [PMID: 29122045 DOI: 10.1017/s1431927617012582] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The composition of GaAs measured by laser-assisted atom probe tomography may be inaccurate depending on the experimental conditions. In this work, we assess the role of the DC field and the impinging laser energy on such compositional bias. The DC field is found to have a major influence, while the laser energy has a weaker one within the range of parameters explored. The atomic fraction of Ga may vary from 0.55 at low-field conditions to 0.35 at high field. These results have been interpreted in terms of preferential evaporation of Ga at high field. The deficit of As is most likely explained by the formation of neutral As complexes either by direct ejection from the tip surface or upon the dissociation of large clusters. The study of multiple detection events supports this interpretation.
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Affiliation(s)
- Enrico Di Russo
- UNIROUEN,INSA Rouen,CNRS,Groupe de Physique des Matériaux,Normandie Université,76000 Rouen,France
| | - Ivan Blum
- UNIROUEN,INSA Rouen,CNRS,Groupe de Physique des Matériaux,Normandie Université,76000 Rouen,France
| | - Jonathan Houard
- UNIROUEN,INSA Rouen,CNRS,Groupe de Physique des Matériaux,Normandie Université,76000 Rouen,France
| | - Gérald Da Costa
- UNIROUEN,INSA Rouen,CNRS,Groupe de Physique des Matériaux,Normandie Université,76000 Rouen,France
| | - Didier Blavette
- UNIROUEN,INSA Rouen,CNRS,Groupe de Physique des Matériaux,Normandie Université,76000 Rouen,France
| | - Lorenzo Rigutti
- UNIROUEN,INSA Rouen,CNRS,Groupe de Physique des Matériaux,Normandie Université,76000 Rouen,France
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Prosa TJ, Larson DJ. Modern Focused-Ion-Beam-Based Site-Specific Specimen Preparation for Atom Probe Tomography. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2017; 23:194-209. [PMID: 28162119 DOI: 10.1017/s1431927616012642] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Approximately 30 years after the first use of focused ion beam (FIB) instruments to prepare atom probe tomography specimens, this technique has grown to be used by hundreds of researchers around the world. This past decade has seen tremendous advances in atom probe applications, enabled by the continued development of FIB-based specimen preparation methodologies. In this work, we provide a short review of the origin of the FIB method and the standard methods used today for lift-out and sharpening, using the annular milling method as applied to atom probe tomography specimens. Key steps for enabling correlative analysis with transmission electron-beam backscatter diffraction, transmission electron microscopy, and atom probe tomography are presented, and strategies for preparing specimens for modern microelectronic device structures are reviewed and discussed in detail. Examples are used for discussion of the steps for each of these methods. We conclude with examples of the challenges presented by complex topologies such as nanowires, nanoparticles, and organic materials.
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Affiliation(s)
- Ty J Prosa
- Cameca Instruments Inc.,5500 Nobel Drive,Madison,WI 53711,USA
| | - David J Larson
- Cameca Instruments Inc.,5500 Nobel Drive,Madison,WI 53711,USA
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Martin AJ, Weng W, Zhu Z, Loesing R, Shaffer J, Katnani A. Cross-sectional atom probe tomography sample preparation for improved analysis of fins on SOI. Ultramicroscopy 2016; 161:105-109. [DOI: 10.1016/j.ultramic.2015.11.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/25/2015] [Accepted: 11/28/2015] [Indexed: 11/25/2022]
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