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Banerjee S, Rodrigues M, Ballester M, Vija AH, Katsaggelos AK. A physics based machine learning model to characterize room temperature semiconductor detectors in 3D. Sci Rep 2024; 14:7803. [PMID: 38565586 PMCID: PMC10987668 DOI: 10.1038/s41598-024-58027-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 03/25/2024] [Indexed: 04/04/2024] Open
Abstract
Room temperature semiconductor radiation detectors (RTSD) for X-ray and γ -ray detection are vital tools for medical imaging, astrophysics and other applications. CdZnTe (CZT) has been the main RTSD for more than three decades with desired detection properties. In a typical pixelated configuration, CZT have electrodes on opposite ends. For advanced event reconstruction algorithms at sub-pixel level, detailed characterization of the RTSD is required in three dimensional (3D) space. However, 3D characterization of the material defects and charge transport properties in the sub-pixel regime is a labor intensive process with skilled manpower and novel experimental setups. Presently, state-of-art characterization is done over the bulk of the RTSD considering homogenous properties. In this paper, we propose a novel physics based machine learning (PBML) model to characterize the RTSD over a discretized sub-pixelated 3D volume which is assumed. Our novel approach is the first to characterize a full 3D charge transport model of the RTSD. In this work, we first discretize the RTSD between a pixelated electrodes spatially into 3 dimensions-x, y, and z. The resulting discretizations are termed as voxels in 3D space. In each voxel, the different physics based charge transport properties such as drift, trapping, detrapping and recombination of charges are modeled as trainable model weights. The drift of the charges considers second order non-linear motion which is observed in practice with the RTSDs. Based on the electron-hole pair injections as input to the PBML model, and signals at the electrodes, free and trapped charges (electrons and holes) as outputs of the model, the PBML model determines the trainable weights by backpropagating the loss function. The trained weights of the model represents one-to-one relation to that of the actual physical charge transport properties in a voxelized detector.
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Affiliation(s)
| | - Miesher Rodrigues
- Siemens Medical Solutions USA, Inc., Hoffman Estates, IL, 60192, USA
| | - Manuel Ballester
- Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
| | - Alexander H Vija
- Siemens Medical Solutions USA, Inc., Hoffman Estates, IL, 60192, USA
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2
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Wang X, Xu Y, Pan Y, Chai S, Wu J, Zhao J, Li Y, Zhao Z, Li Q, Wu J, Chen J, Bae BS, Zhou J, Zhu Y, Lei W, Xu X. Using N-I-N Photodiodes Made of Perovskite Single Crystals for Low Noise Gamma-Ray Spectroscopy. ACS APPLIED MATERIALS & INTERFACES 2024; 16:12106-12114. [PMID: 38410909 DOI: 10.1021/acsami.4c00432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Solution-processed lead halide perovskite single crystals (LHPSCs) are believed to have great potential in gamma-ray spectroscopy. However, obtaining low-defect LHPSCs from a solution at low temperatures is difficult compared to obtaining Bridgman single crystals such as CdTe and Si. Herein, noise from the intrinsic defects of LHPSCs is considered as the main problem hindering their gamma-ray detection performance. By isolating the defect-induced holes in LHPSCs via energy barriers, we show that NIN photodiodes based on three types of LHPSCs, i.e., MAPbBr3 (MA = CH3NH3), MAPbBr2.5Cl0.5, and cascade LHPSCs, have demonstrated good energy resolution in the range of 6.7-10.3% for 662 keV 137Cs gamma-ray photons. The noise for >10 mm3 devices is low, in the order of 340-860 electrons, and the electron collection efficiency reaches 23-43%. These results pave the way for obtaining low-cost, large, high energy-resolution gamma-ray detectors at room temperature (300 K).
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Affiliation(s)
- Xin Wang
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Yubing Xu
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Yuzhu Pan
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Shunjie Chai
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Jie Wu
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Jingda Zhao
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Yuwei Li
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Zhiwei Zhao
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Qing Li
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Jun Wu
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Jing Chen
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Byung Seong Bae
- Department of Electronics &Display Engineering, Hoseo University, Hoseo Ro 79, Asan City, Chungnam 31499, Republic of Korea
| | | | - Ying Zhu
- E-spectrum Optoelectronic Co. Ltd., Suzhou 215111, China
| | - Wei Lei
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
| | - Xiaobao Xu
- School of Electronic Science and Engineering, Southeast University, Nanjing 210000, China
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3
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Masłowska A, Kochanowska DM, Sulich A, Domagala JZ, Dopierała M, Kochański M, Szot M, Chromiński W, Mycielski A. Bridgman-Grown (Cd,Mn)Te and (Cd,Mn)(Te,Se): A Comparison of Suitability for X and Gamma Detectors. SENSORS (BASEL, SWITZERLAND) 2024; 24:345. [PMID: 38257444 PMCID: PMC10819988 DOI: 10.3390/s24020345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 12/30/2023] [Accepted: 01/04/2024] [Indexed: 01/24/2024]
Abstract
This study explores the suitability of (Cd,Mn)Te and (Cd,Mn)(Te,Se) as room-temperature X-ray and gamma-ray detector materials, grown using the Bridgman method. The investigation compares their crystal structure, mechanical and optical properties, and radiation detection capabilities. Both crystals can yield large-area single crystal samples measuring approximately 30 × 30 mm2. In low-temperature photoluminescence analysis, both materials showed defect states, and annealing in cadmium vapors effectively eliminated donor-acceptor pair luminescence in (Cd,Mn)Te but not in (Cd,Mn)(Te,Se). Moreover, harder (Cd,Mn)(Te,Se) exhibited a higher etch pit density compared to softer (Cd,Mn)Te. X-ray diffraction examination revealed uniform lattice constant distribution in both compounds, with variations at a part per million level. (Cd,Mn)Te crystals demonstrated excellent single crystal properties with narrower omega scan widths, while (Cd,Mn)(Te,Se) exhibited a high contribution of block-like structures with significantly larger misorientation angles. Spectroscopic evaluations revealed better performance of a pixelated (Cd,Mn)Te detector, in comparison to (Cd,Mn)(Te,Se), achieving a mean full width at half maximum of 14% for the 122 keV gamma peak of Co-57. The reduced performance of the (Cd,Mn)(Te,Se) detector may be attributed to deep trap-related luminescence or block-like structures with larger misorientation angles. In conclusion, Bridgman-grown (Cd,Mn)Te emerges as a more promising material for X-ray and gamma-ray detectors when compared to (Cd,Mn)(Te,Se).
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Affiliation(s)
- Aneta Masłowska
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
| | - Dominika M. Kochanowska
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
| | - Adrian Sulich
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
| | - Jaroslaw Z. Domagala
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
| | - Marcin Dopierała
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
| | - Michał Kochański
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
| | - Michał Szot
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
- International Research Centre MagTop, Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland
| | - Witold Chromiński
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141, 02-507 Warsaw, Poland;
| | - Andrzej Mycielski
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668 Warsaw, Poland; (D.M.K.); (A.S.); (J.Z.D.); (M.D.); (M.K.); (M.S.)
- Puremat Technologies Sp. z o.o., Aleja Lotników 32/46, 02-668 Warsaw, Poland
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Banerjee S, Rodrigues M, Ballester M, Vija AH, Katsaggelos A. Identifying Defects without a priori Knowledge in a Room-Temperature Semiconductor Detector Using Physics Inspired Machine Learning Model. SENSORS (BASEL, SWITZERLAND) 2023; 24:92. [PMID: 38202954 PMCID: PMC10781357 DOI: 10.3390/s24010092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/16/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024]
Abstract
Room-temperature semiconductor radiation detectors (RTSD) such as CdZnTe are popular in Computed Tomography (CT) imaging and other applications. Transport properties and material defects with respect to electron and hole transport often need to be characterized, which is a labor intensive process. However, these defects often vary from one RTSD to another and are not known a priori during characterization of the material. In recent years, physics-inspired machine learning (PI-ML) models have been developed for the RTSDs which have the ability to characterize the defects in a RTSD by discretizing it volumetrically. These learning models capture the heterogeneity of the defects in the RTSD-which arises due to the fabrication process and the energy bands of elements in the RTSD. In those models, the different defects of RTSD-trapping, detrapping and recombination for electrons and holes-are present. However, these defects are often unknown. In this work, we show the capabilities of a PI-ML model which has been developed considering all the material defects to identify certain defects which are present (or absent). Additionally, these models can identify the defects over the volume of the RTSD in a discretized manner.
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Affiliation(s)
- Srutarshi Banerjee
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL 60208, USA; (M.B.); (A.K.)
| | - Miesher Rodrigues
- Siemens Medical Solutions USA, Inc., Hoffmann Estates, IL 60192, USA; (M.R.); (A.H.V.)
| | - Manuel Ballester
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL 60208, USA; (M.B.); (A.K.)
| | - Alexander Hans Vija
- Siemens Medical Solutions USA, Inc., Hoffmann Estates, IL 60192, USA; (M.R.); (A.H.V.)
| | - Aggelos Katsaggelos
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL 60208, USA; (M.B.); (A.K.)
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5
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Bettelli M, Zanettini S, Abbene L, Casoli F, Nasi L, Trevisi G, Principato F, Buttacavoli A, Zappettini A. High performance platinum contacts on high-flux CdZnTe detectors. Sci Rep 2023; 13:17963. [PMID: 37864099 PMCID: PMC10589347 DOI: 10.1038/s41598-023-45331-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 10/18/2023] [Indexed: 10/22/2023] Open
Abstract
The need for direct X-ray detection under high photon flux with moderate or high energies (30-100 keV range) has strongly increased with the rise of the 4th Generation Synchrotron Light Sources, characterised by extremely brilliant beamlines, and of other applications such as spectral computed tomography in medicine and non-destructive tests for industry. The novel Cadmium Zinc Telluride (CZT) developed by Redlen Technologies can be considered the reference material for high-flux applications (HF-CZT). The enhanced charge transport properties of the holes allow the mitigation of the effects of radiation induced polarization phenomena, typically observed in standard CZT materials (LF-CZT) under high photon flux. However, standard LF-CZT electrical contacts led to inacceptable high dark leakage currents on HF-CZT devices. In this work, a detailed study on the characteristics of new optimized sputtered platinum electrical contacts on HF-CZT detectors is reported. The results from electrical and spectroscopic investigations, showed the best performances on HF-CZT detectors with platinum anode, coupled with both platinum or gold cathode. The morphology, structure, and composition of Pt/CZT contact have been analysed by means of Transmission Electron Microscopy (TEM) on microscopic lamellas obtained by Focused Ion Beam (FIB), highlighting the presence of CdTeO3 oxide at the metal semiconductor interface.
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Affiliation(s)
| | | | - Leonardo Abbene
- Department of Physics and Chemistry (DiFC) - Emilio Segrè, University of Palermo, 90128, Palermo, Italy
| | | | | | | | - Fabio Principato
- Department of Physics and Chemistry (DiFC) - Emilio Segrè, University of Palermo, 90128, Palermo, Italy
| | - Antonino Buttacavoli
- Department of Physics and Chemistry (DiFC) - Emilio Segrè, University of Palermo, 90128, Palermo, Italy
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6
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Principato F, Bettelli M, Zappettini A, Abbene L. A Novel Extraction Procedure of Contact Characteristic Parameters from Current-Voltage Curves in CdZnTe and CdTe Detectors. SENSORS (BASEL, SWITZERLAND) 2023; 23:6075. [PMID: 37447923 DOI: 10.3390/s23136075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/15/2023]
Abstract
The estimation of the characteristic parameters of the electrical contacts in CdZnTe and CdTe detectors is related to the identification of the main transport mechanisms dominating the currents. These investigations are typically approached by modelling the current-voltage (I-V) curves with the interfacial layer-thermionic-diffusion (ITD) theory, which incorporates the thermionic emission, diffusion and interfacial layer theories into a single theory. The implementation of the ITD model in measured I-V curves is a critical procedure, requiring dedicated simplifications, several best fitting parameters and the identification of the voltage range where each transport mechanism dominates. In this work, we will present a novel method allowing through a simple procedure the estimation of some characteristic parameters of the metal-semiconductor interface in CdZnTe and CdTe detectors. The barrier height and the effects of the interfacial layer will be evaluated through the application of a new function related to the differentiation of the experimental I-V curves.
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Affiliation(s)
- Fabio Principato
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | | | | | - Leonardo Abbene
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
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7
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Cola A, Dominici L, Valletta A. Electric-Field Mapping of Optically Perturbed CdTe Radiation Detectors. SENSORS (BASEL, SWITZERLAND) 2023; 23:4795. [PMID: 37430709 DOI: 10.3390/s23104795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/12/2023] [Accepted: 05/13/2023] [Indexed: 07/12/2023]
Abstract
In radiation detectors, the spatial distribution of the electric field plays a fundamental role in their operation. Access to this field distribution is of strategic importance, especially when investigating the perturbing effects induced by incident radiation. For example, one dangerous effect that prevents their proper operation is the accumulation of internal space charge. Here, we probe the two-dimensional electric field in a Schottky CdTe detector using the Pockels effect and report on its local perturbation after exposure to an optical beam at the anode electrode. Our electro-optical imaging setup, together with a custom processing routine, allows the extraction of the electric-field vector maps and their dynamics during a voltage bias-optical exposure sequence. The results are in agreement with numerical simulations, allowing us to confirm a two-level model based on a dominant deep level. Such a simple model is indeed able to fully account for both the temporal and spatial dynamics of the perturbed electric field. This approach thus allows a deeper understanding of the main mechanisms affecting the non-equilibrium electric-field distribution in CdTe Schottky detectors, such as those leading to polarization. In the future, it could also be used to predict and improve the performance of planar or electrode-segmented detectors.
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Affiliation(s)
- Adriano Cola
- Institute for Microelectronics and Microsystems, IMM-CNR, Via Monteroni, 73100 Lecce, Italy
| | - Lorenzo Dominici
- Institute of Nanotechnology, NANOTEC-CNR, Via Monteroni, 73100 Lecce, Italy
| | - Antonio Valletta
- Institute for Microelectronics and Microsystems, IMM-CNR, Via Del Fosso Del Cavaliere, 100, 00133 Rome, Italy
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8
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Optimization of quasi-hemispherical CdZnTe detectors by means of first principles simulation. Sci Rep 2023; 13:3212. [PMID: 36828862 PMCID: PMC9958116 DOI: 10.1038/s41598-023-30181-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 02/17/2023] [Indexed: 02/26/2023] Open
Abstract
In this paper we present the development of quasi-hemispherical gamma-ray detectors based on CdZnTe. Among the possible single-polarity electrode configurations, such as coplanar, pixelated, or virtual Frisch-grid geometries, quasi-hemispherical detectors are the most cost-effective alternative with comparable raw energy resolution in the high and low energy range. The optimal configuration of the sensor in terms of dimension of the crystals and electrode specifications has been first determined by simulations, and successively validated with experimental measures. Spectra from different sources have been acquired to evaluate the detectors performances. Three types of detectors with different CZT volumes have been fabricated, namely 10 × 10 × 5 mm3, 15 × 15 × 10 mm3 and 20 × 20 × 10 mm3. In the case of 10 × 10 × 5 mm3 crystals, the optimum pixel size determined by our simulation tool was confirmed by experiments: the best spectroscopic resolution of 1.3% at 662 keV has been found for a 750 μm diameter pixel detector. The best energy resolution values obtained for the 15 × 15 × 10 mm3 and 20 × 20 × 10 mm3 detectors were respectively 1.7% and 2.7% at 662 keV.
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Mele F, Quercia J, Abbene L, Benassi G, Bettelli M, Buttacavoli A, Principato F, Zappettini A, Bertuccio G. Advances in High-Energy-Resolution CdZnTe Linear Array Pixel Detectors with Fast and Low Noise Readout Electronics. SENSORS (BASEL, SWITZERLAND) 2023; 23:2167. [PMID: 36850765 PMCID: PMC9960822 DOI: 10.3390/s23042167] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/04/2023] [Accepted: 02/10/2023] [Indexed: 06/18/2023]
Abstract
Radiation detectors based on Cadmium Zinc Telluride (CZT) compounds are becoming popular solutions thanks to their high detection efficiency, room temperature operation, and to their reliability in compact detection systems for medical, astrophysical, or industrial applications. However, despite a huge effort to improve the technological process, CZT detectors' full potential has not been completely exploited when both high spatial and energy resolution are required by the application, especially at low energies (<10 keV), limiting their application in energy-resolved photon counting (ERPC) systems. This gap can also be attributed to the lack of dedicated front-end electronics which can bring out the best in terms of detector spectroscopic performances. In this work, we present the latest results achieved in terms of energy resolution using SIRIO, a fast low-noise charge sensitive amplifier, and a linear-array pixel detector, based on boron oxide encapsulated vertical Bridgman-grown B-VB CZT crystals. The detector features a 0.25-mm pitch, a 1-mm thickness and is operated at a -700-V bias voltage. An equivalent noise charge of 39.2 el. r.m.s. (corresponding to 412 eV FWHM) was measured on the test pulser at 32 ns peaking time, leading to a raw resolution of 1.3% (782 eV FWHM) on the 59 keV line at room temperature (+20 °C) using an uncollimated 241Am, largely improving the current state of the art for CZT-based detection systems at such short peaking times, and achieving an optimum resolution of 0.97% (576 eV FWHM) at 1 µs peaking time. The measured energy resolution at the 122 keV line and with 1 µs peaking time of a 57Co raw uncollimated spectrum is 0.96% (1.17 keV). These activities are in the framework of an Italian collaboration on the development of energy-resolved X-ray scanners for material recycling, medical applications, and non-destructive testing in the food industry.
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Affiliation(s)
- Filippo Mele
- Department of Electronics, Information and Bioengineering (DEIB), Politecnico di Milano, Via Anzani 42, 22100 Como, Italy
- National Institute of Nuclear Physics (INFN), Sezione di Milano, Via Celoria 16, 22133 Milan, Italy
| | - Jacopo Quercia
- Department of Electronics, Information and Bioengineering (DEIB), Politecnico di Milano, Via Anzani 42, 22100 Como, Italy
| | - Leonardo Abbene
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | - Giacomo Benassi
- Due2lab s.r.l., Via Paolo Borsellino 2, 42019 Scandiano, Italy
| | | | - Antonino Buttacavoli
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | - Fabio Principato
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | | | - Giuseppe Bertuccio
- Department of Electronics, Information and Bioengineering (DEIB), Politecnico di Milano, Via Anzani 42, 22100 Como, Italy
- National Institute of Nuclear Physics (INFN), Sezione di Milano, Via Celoria 16, 22133 Milan, Italy
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10
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Banerjee S, Rodrigues M, Ballester M, Vija AH, Katsaggelos AK. Learning-based physical models of room-temperature semiconductor detectors with reduced data. Sci Rep 2023; 13:168. [PMID: 36599876 PMCID: PMC9813153 DOI: 10.1038/s41598-022-27125-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 12/26/2022] [Indexed: 01/05/2023] Open
Abstract
Room-temperature semiconductor radiation detectors (RTSD) have broad applications in medical imaging, homeland security, astrophysics and others. RTSDs such as CdZnTe, CdTe are often pixelated, and characterization of these detectors at micron level can benefit 3-D event reconstruction at sub-pixel level. Material defects alongwith electron and hole charge transport properties need to be characterized which requires several experimental setups and is labor intensive. The current state-of-art approaches characterize each detector pixel, considering the detector in bulk. In this article, we propose a new microscopic learning-based physical models of RTSD based on limited data compared to what is dictated by the physical equations. Our learning models uses a physical charge transport considering trapping centers. Our models learn these material properties in an indirect manner from the measurable signals at the electrodes and/or free and/or trapped charges distributed in the RTSD for electron-hole charge pair injections in the material. Based on the amount of data used during training our physical model, our algorithm characterizes the detector for charge drifts, trapping, detrapping and recombination coefficients considering multiple trapping centers or as a single equivalent trapping center. The RTSD is segmented into voxels spatially, and in each voxel, the material properties are modeled as learnable parameters. Depending on the amount of data, our models can characterize the RTSD either completely or in an equivalent manner.
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Affiliation(s)
- Srutarshi Banerjee
- grid.16753.360000 0001 2299 3507Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 USA
| | | | - Manuel Ballester
- grid.16753.360000 0001 2299 3507Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 USA
| | | | - Aggelos K. Katsaggelos
- grid.16753.360000 0001 2299 3507Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 USA
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11
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Huang C, Wilson MD, Suzuki K, Liotti E, Connolley T, Magdysyuk OV, Collins S, Van Assche F, Boone MN, Veale MC, Lui A, Wheater R, Leung CLA. 3D Correlative Imaging of Lithium Ion Concentration in a Vertically Oriented Electrode Microstructure with a Density Gradient. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2105723. [PMID: 35404540 PMCID: PMC9165496 DOI: 10.1002/advs.202105723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 03/10/2022] [Indexed: 06/14/2023]
Abstract
The performance of Li+ ion batteries (LIBs) is hindered by steep Li+ ion concentration gradients in the electrodes. Although thick electrodes (≥300 µm) have the potential for reducing the proportion of inactive components inside LIBs and increasing battery energy density, the Li+ ion concentration gradient problem is exacerbated. Most understanding of Li+ ion diffusion in the electrodes is based on computational modeling because of the low atomic number (Z) of Li. There are few experimental methods to visualize Li+ ion concentration distribution of the electrode within a battery of typical configurations, for example, coin cells with stainless steel casing. Here, for the first time, an interrupted in situ correlative imaging technique is developed, combining novel, full-field X-ray Compton scattering imaging with X-ray computed tomography that allows 3D pixel-by-pixel mapping of both Li+ stoichiometry and electrode microstructure of a LiNi0.8 Mn0.1 Co0.1 O2 cathode to correlate the chemical and physical properties of the electrode inside a working coin cell battery. An electrode microstructure containing vertically oriented pore arrays and a density gradient is fabricated. It is shown how the designed electrode microstructure improves Li+ ion diffusivity, homogenizes Li+ ion concentration through the ultra-thick electrode (1 mm), and improves utilization of electrode active materials.
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Affiliation(s)
- Chun Huang
- Department of MaterialsImperial College LondonLondonSW7 2AZUK
- The Faraday InstitutionQuad One, Becquerel Ave, Harwell CampusDidcotOX11 0RAUK
- Department of MaterialsUniversity of OxfordOxfordOX1 3PHUK
- Research Complex at HarwellRutherford Appleton LaboratoryDidcotOxfordshireOX11 0FAUK
- Department of EngineeringKing's College LondonLondonWC2R 2LSUK
| | - Matthew D. Wilson
- STFC‐UKRIRutherford Appleton LaboratoryHarwell CampusDidcotOxfordshireOX11 0QXUK
| | - Kosuke Suzuki
- Faculty of Science and TechnologyGunma University1‐5‐1 Tenjin‐cho, KiryuGunma376‐8515Japan
| | - Enzo Liotti
- Department of MaterialsUniversity of OxfordOxfordOX1 3PHUK
| | - Thomas Connolley
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOxfordshireOX11 0QXUK
| | - Oxana V. Magdysyuk
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOxfordshireOX11 0QXUK
| | - Stephen Collins
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOxfordshireOX11 0QXUK
| | - Frederic Van Assche
- Radiation PhysicsDepartment of Physics and AstronomyFaculty of SciencesGhent UniversityProeftuinstraat 86/N12Gent9000Belgium
| | - Matthieu N. Boone
- Radiation PhysicsDepartment of Physics and AstronomyFaculty of SciencesGhent UniversityProeftuinstraat 86/N12Gent9000Belgium
| | - Matthew C. Veale
- STFC‐UKRIRutherford Appleton LaboratoryHarwell CampusDidcotOxfordshireOX11 0QXUK
| | - Andrew Lui
- Department of MaterialsUniversity of OxfordOxfordOX1 3PHUK
| | - Rhian‐Mair Wheater
- STFC‐UKRIRutherford Appleton LaboratoryHarwell CampusDidcotOxfordshireOX11 0QXUK
| | - Chu Lun Alex Leung
- Research Complex at HarwellRutherford Appleton LaboratoryDidcotOxfordshireOX11 0FAUK
- Department of Mechanical EngineeringUniversity College LondonLondonWC1E 7JEUK
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12
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Buttacavoli A, Principato F, Gerardi G, Bettelli M, Zappettini A, Seller P, Veale MC, Zanettini S, Abbene L. Ballistic Deficit Pulse Processing in Cadmium-Zinc-Telluride Pixel Detectors for High-Flux X-ray Measurements. SENSORS 2022; 22:s22093409. [PMID: 35591099 PMCID: PMC9103549 DOI: 10.3390/s22093409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/24/2022] [Accepted: 04/27/2022] [Indexed: 01/25/2023]
Abstract
High-flux X-ray measurements with high-energy resolution and high throughput require the mitigation of pile-up and dead time effects. The reduction of the time width of the shaped pulses is a key approach, taking into account the distortions from the ballistic deficit, non-linearity, and time instabilities. In this work, we will present the performance of cadmium−zinc−telluride (CdZnTe or CZT) pixel detectors equipped with digital shapers faster than the preamplifier peaking times (ballistic deficit pulse processing). The effects on energy resolution, throughput, energy-linearity, time stability, charge sharing, and pile-up are shown. The results highlight the absence of time instabilities and high-energy resolution (<4% FWHM at 122 keV) when ballistic deficit pulse processing (dead time of 90 ns) was used in CZT pixel detectors. These activities are in the framework of an international collaboration on the development of spectroscopic imagers for medical applications (mammography, computed tomography) and non-destructive testing in the food industry.
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Affiliation(s)
- Antonino Buttacavoli
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.)
| | - Fabio Principato
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.)
| | - Gaetano Gerardi
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.)
| | - Manuele Bettelli
- IMEM/CNR, Parco Area delle Scienze 37/A, 43100 Parma, Italy; (M.B.); (A.Z.)
| | - Andrea Zappettini
- IMEM/CNR, Parco Area delle Scienze 37/A, 43100 Parma, Italy; (M.B.); (A.Z.)
| | - Paul Seller
- UKRI Science & Technology Facilities Council, Didcot OX11 0QX, UK; (P.S.); (M.C.V.)
| | - Matthew C. Veale
- UKRI Science & Technology Facilities Council, Didcot OX11 0QX, UK; (P.S.); (M.C.V.)
| | | | - Leonardo Abbene
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.)
- Correspondence:
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13
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Buttacavoli A, Principato F, Gerardi G, Cascio D, Raso G, Bettelli M, Zappettini A, Seller P, Veale MC, Abbene L. Incomplete Charge Collection at Inter-Pixel Gap in Low- and High-Flux Cadmium Zinc Telluride Pixel Detectors. SENSORS 2022; 22:s22041441. [PMID: 35214342 PMCID: PMC8875842 DOI: 10.3390/s22041441] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 02/01/2023]
Abstract
The success of cadmium zinc telluride (CZT) detectors in room-temperature spectroscopic X-ray imaging is now widely accepted. The most common CZT detectors are characterized by enhanced-charge transport properties of electrons, with mobility-lifetime products μeτe > 10−2 cm2/V and μhτh > 10−5 cm2/V. These materials, typically termed low-flux LF-CZT, are successfully used for thick electron-sensing detectors and in low-flux conditions. Recently, new CZT materials with hole mobility-lifetime product enhancements (μhτh > 10−4 cm2/V and μeτe > 10−3 cm2/V) have been fabricated for high-flux measurements (high-flux HF-CZT detectors). In this work, we will present the performance and charge-sharing properties of sub-millimeter CZT pixel detectors based on LF-CZT and HF-CZT crystals. Experimental results from the measurement of energy spectra after charge-sharing addition (CSA) and from 2D X-ray mapping highlight the better charge-collection properties of HF-CZT detectors near the inter-pixel gaps. The successful mitigation of the effects of incomplete charge collection after CSA was also performed through original charge-sharing correction techniques. These activities exist in the framework of international collaboration on the development of energy-resolved X-ray scanners for medical applications and non-destructive testing in the food industry.
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Affiliation(s)
- Antonino Buttacavoli
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale Delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.); (D.C.); (G.R.)
| | - Fabio Principato
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale Delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.); (D.C.); (G.R.)
| | - Gaetano Gerardi
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale Delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.); (D.C.); (G.R.)
| | - Donato Cascio
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale Delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.); (D.C.); (G.R.)
| | - Giuseppe Raso
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale Delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.); (D.C.); (G.R.)
| | - Manuele Bettelli
- IMEM/CNR, Parco Area delle Scienze 37/A, 43100 Parma, Italy; (M.B.); (A.Z.)
| | - Andrea Zappettini
- IMEM/CNR, Parco Area delle Scienze 37/A, 43100 Parma, Italy; (M.B.); (A.Z.)
| | - Paul Seller
- Rutherford Appleton Laboratory, UKRI Science & Technology Facilities Council, Oxon OX11 0QX, UK; (P.S.); (M.C.V.)
| | - Matthew C. Veale
- Rutherford Appleton Laboratory, UKRI Science & Technology Facilities Council, Oxon OX11 0QX, UK; (P.S.); (M.C.V.)
| | - Leonardo Abbene
- Department of Physics and Chemistry (DiFC)—Emilio Segrè, University of Palermo, Viale Delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (F.P.); (G.G.); (D.C.); (G.R.)
- Correspondence:
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14
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Buttacavoli A, Gerardi G, Principato F, Mirabello M, Cascio D, Raso G, Bettelli M, Zappettini A, Seller P, Veale MC, Abbene L. Energy Recovery of Multiple Charge Sharing Events in Room Temperature Semiconductor Pixel Detectors. SENSORS 2021; 21:s21113669. [PMID: 34070426 PMCID: PMC8197486 DOI: 10.3390/s21113669] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/03/2021] [Accepted: 05/23/2021] [Indexed: 11/20/2022]
Abstract
Multiple coincidence events from charge-sharing and fluorescent cross-talk are typical drawbacks in room-temperature semiconductor pixel detectors. The mitigation of these distortions in the measured energy spectra, using charge-sharing discrimination (CSD) and charge-sharing addition (CSA) techniques, is always a trade-off between counting efficiency and energy resolution. The energy recovery of multiple coincidence events is still challenging due to the presence of charge losses after CSA. In this work, we will present original techniques able to correct charge losses after CSA even when multiple pixels are involved. Sub-millimeter cadmium–zinc–telluride (CdZnTe or CZT) pixel detectors were investigated with both uncollimated radiation sources and collimated synchrotron X rays, at energies below and above the K-shell absorption energy of the CZT material. These activities are in the framework of an international collaboration on the development of energy-resolved photon counting (ERPC) systems for spectroscopic X-ray imaging up to 150 keV.
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Affiliation(s)
- Antonino Buttacavoli
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (G.G.); (F.P.); (M.M.); (D.C.); (G.R.)
| | - Gaetano Gerardi
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (G.G.); (F.P.); (M.M.); (D.C.); (G.R.)
| | - Fabio Principato
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (G.G.); (F.P.); (M.M.); (D.C.); (G.R.)
| | - Marcello Mirabello
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (G.G.); (F.P.); (M.M.); (D.C.); (G.R.)
| | - Donato Cascio
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (G.G.); (F.P.); (M.M.); (D.C.); (G.R.)
| | - Giuseppe Raso
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (G.G.); (F.P.); (M.M.); (D.C.); (G.R.)
| | - Manuele Bettelli
- IMEM/CNR, Parco Area delle Scienze 37/A, 43100 Parma, Italy; (M.B.); (A.Z.)
| | - Andrea Zappettini
- IMEM/CNR, Parco Area delle Scienze 37/A, 43100 Parma, Italy; (M.B.); (A.Z.)
| | - Paul Seller
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton OX11 0QX, UK; (P.S.); (M.C.V.)
| | - Matthew C. Veale
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton OX11 0QX, UK; (P.S.); (M.C.V.)
| | - Leonardo Abbene
- Department of Physics and Chemistry (DiFC)-Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy; (A.B.); (G.G.); (F.P.); (M.M.); (D.C.); (G.R.)
- Correspondence:
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15
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Charge Sharing and Charge Loss in High-Flux Capable Pixelated CdZnTe Detectors. SENSORS 2021; 21:s21093260. [PMID: 34066764 PMCID: PMC8125915 DOI: 10.3390/s21093260] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/26/2021] [Accepted: 05/06/2021] [Indexed: 12/03/2022]
Abstract
Cadmium zinc telluride (CdZnTe) detectors are known to suffer from polarization effects under high photon flux due to poor hole transport in the crystal material. This has led to the development of a high-flux capable CdZnTe material (HF-CdZnTe). Detectors with the HF-CdZnTe material have shown promising results at mitigating the onset of the polarization phenomenon, likely linked to improved crystal quality and hole carrier transport. Better hole transport will have an impact on charge collection, particularly in pixelated detector designs and thick sensors (>1 mm). In this paper, the presence of charge sharing and the magnitude of charge loss were calculated for a 2 mm thick pixelated HF-CdZnTe detector with 250 μm pixel pitch and 25 μm pixel gaps, bonded to the STFC HEXITEC ASIC. Results are compared with a CdTe detector as a reference point and supported with simulations from a Monte-Carlo detector model. Charge sharing events showed minimal charge loss in the HF-CdZnTe, resulting in a spectral resolution of 1.63 ± 0.08 keV Full Width at Half Maximum (FWHM) for bipixel charge sharing events at 59.5 keV. Depth of interaction effects were shown to influence charge loss in shared events. The performance is discussed in relation to the improved hole transport of HF-CdZnTe and comparison with simulated results provided evidence of a uniform electric field.
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16
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Paton KA, Veale MC, Mu X, Allen CS, Maneuski D, Kübel C, O'Shea V, Kirkland AI, McGrouther D. Quantifying the performance of a hybrid pixel detector with GaAs:Cr sensor for transmission electron microscopy. Ultramicroscopy 2021; 227:113298. [PMID: 34051540 DOI: 10.1016/j.ultramic.2021.113298] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 02/01/2021] [Accepted: 04/24/2021] [Indexed: 10/21/2022]
Abstract
Hybrid pixel detectors (HPDs) have been shown to be highly effective for diffraction-based and time-resolved studies in transmission electron microscopy, but their performance is limited by the fact that high-energy electrons scatter over long distances in their thick Si sensors. An advantage of HPDs compared to monolithic active pixel sensors is that their sensors do not need to be fabricated from Si. We have compared the performance of the Medipix3 HPD with a Si sensor and a GaAs:Cr sensor using primary electrons in the energy range of 60-300 keV. We describe the measurement and calculation of the detectors' modulation transfer function (MTF) and detective quantum efficiency (DQE), which show that the performance of the GaAs:Cr device is markedly superior to that of the Si device for high-energy electrons.
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Affiliation(s)
- Kirsty A Paton
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, G12 8QQ, UK.
| | - Matthew C Veale
- UKRI Science & Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK
| | - Xiaoke Mu
- Karlsruhe Nano Micro Facility, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
| | - Christopher S Allen
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK; electron Physical Sciences Imaging Centre (ePSIC), Diamond Lightsource Ltd., Didcot, OX11 0DE, UK
| | - Dzmitry Maneuski
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, G12 8QQ, UK
| | - Christian Kübel
- Karlsruhe Nano Micro Facility, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany; Department of Materials and Earth Science, Technische Universität Darmstadt and Karlsruhe Institute of Technology, Otto-Berndt-Str. 3, 64287 Darmstadt, Germany
| | - Val O'Shea
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, G12 8QQ, UK
| | - Angus I Kirkland
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK; electron Physical Sciences Imaging Centre (ePSIC), Diamond Lightsource Ltd., Didcot, OX11 0DE, UK
| | - Damien McGrouther
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, G12 8QQ, UK
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17
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Tsigaridas S, Zanettini S, Bettelli M, Amadè NS, Calestani D, Ponchut C, Zappettini A. Fabrication of Small-Pixel CdZnTe Sensors and Characterization with X-rays. SENSORS 2021; 21:s21092932. [PMID: 33922055 PMCID: PMC8122653 DOI: 10.3390/s21092932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/18/2021] [Accepted: 04/21/2021] [Indexed: 11/23/2022]
Abstract
Over the past few years, sensors made from high-Z compound semiconductors have attracted quite some attention for use in applications which require the direct detection of X-rays in the energy range 30–100 keV. One of the candidate materials with promising properties is cadmium zinc telluride (CdZnTe). In the context of this article, we have developed pixelated sensors from CdZnTe crystals grown by Boron oxide encapsulated vertical Bridgman technique. We demonstrate the successful fabrication of CdZnTe pixel sensors with a fine pitch of 55 m and thickness of 1 mm and 2 mm. The sensors were bonded on Timepix readout chips to evaluate their response to X-rays provided by conventional sources. Despite the issues related to single-chip fabrication procedure, reasonable uniformity was achieved along with low leakage current values at room temperature. In addition, the sensors show stable performance over time at moderate incoming fluxes, below 106 photons mm−2s−1.
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Affiliation(s)
- Stergios Tsigaridas
- European Synchrotron Radiation Facility (ESRF), 71 Avenue des Martyrs, F-38043 Grenoble, France;
- Correspondence:
| | | | - Manuele Bettelli
- IMEM-CNR, Istituto Materiali per l’Elettronica e il Magnetismo, Consiglio Nazionale delle Ricerche, Parco Area delle Scienze 37/A, 43124 Parma, Italy; (M.B.); (N.S.A.); (D.C.); (A.Z.)
| | - Nicola Sarzi Amadè
- IMEM-CNR, Istituto Materiali per l’Elettronica e il Magnetismo, Consiglio Nazionale delle Ricerche, Parco Area delle Scienze 37/A, 43124 Parma, Italy; (M.B.); (N.S.A.); (D.C.); (A.Z.)
| | - Davide Calestani
- IMEM-CNR, Istituto Materiali per l’Elettronica e il Magnetismo, Consiglio Nazionale delle Ricerche, Parco Area delle Scienze 37/A, 43124 Parma, Italy; (M.B.); (N.S.A.); (D.C.); (A.Z.)
| | - Cyril Ponchut
- European Synchrotron Radiation Facility (ESRF), 71 Avenue des Martyrs, F-38043 Grenoble, France;
| | - Andrea Zappettini
- IMEM-CNR, Istituto Materiali per l’Elettronica e il Magnetismo, Consiglio Nazionale delle Ricerche, Parco Area delle Scienze 37/A, 43124 Parma, Italy; (M.B.); (N.S.A.); (D.C.); (A.Z.)
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18
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Abbene L, Gerardi G, Principato F, Buttacavoli A, Altieri S, Protti N, Tomarchio E, Del Sordo S, Auricchio N, Bettelli M, Amadè NS, Zanettini S, Zappettini A, Caroli E. Recent advances in the development of high-resolution 3D cadmium-zinc-telluride drift strip detectors. JOURNAL OF SYNCHROTRON RADIATION 2020; 27:1564-1576. [PMID: 33147181 DOI: 10.1107/s1600577520010747] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
In the last two decades, great efforts have been made in the development of 3D cadmium-zinc-telluride (CZT) detectors operating at room temperature for gamma-ray spectroscopic imaging. This work presents the spectroscopic performance of new high-resolution CZT drift strip detectors, recently developed at IMEM-CNR of Parma (Italy) in collaboration with due2lab (Italy). The detectors (19.4 mm × 19.4 mm × 6 mm) are organized into collecting anode strips (pitch of 1.6 mm) and drift strips (pitch of 0.4 mm) which are negatively biased to optimize electron charge collection. The cathode is divided into strips orthogonal to the anode strips with a pitch of 2 mm. Dedicated pulse processing analysis was performed on a wide range of collected and induced charge pulse shapes using custom 32-channel digital readout electronics. Excellent room-temperature energy resolution (1.3% FWHM at 662 keV) was achieved using the detectors without any spectral corrections. Further improvements (0.8% FWHM at 662 keV) were also obtained through a novel correction technique based on the analysis of collected-induced charge pulses from anode and drift strips. These activities are in the framework of two Italian research projects on the development of spectroscopic gamma-ray imagers (10-1000 keV) for astrophysical and medical applications.
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Affiliation(s)
- Leonardo Abbene
- Department of Physics and Chemistry (DiFC), University of Palermo, Viale delle Scienze, Edificio 18, Palermo 90128, Italy
| | - Gaetano Gerardi
- Department of Physics and Chemistry (DiFC), University of Palermo, Viale delle Scienze, Edificio 18, Palermo 90128, Italy
| | - Fabio Principato
- Department of Physics and Chemistry (DiFC), University of Palermo, Viale delle Scienze, Edificio 18, Palermo 90128, Italy
| | - Antonino Buttacavoli
- Department of Physics and Chemistry (DiFC), University of Palermo, Viale delle Scienze, Edificio 18, Palermo 90128, Italy
| | - Saverio Altieri
- Nuclear Physics National Institute (INFN), Unit of Pavia, via Agostino Bassi 6, Pavia 27100, Italy
| | - Nicoletta Protti
- Nuclear Physics National Institute (INFN), Unit of Pavia, via Agostino Bassi 6, Pavia 27100, Italy
| | - Elio Tomarchio
- Department of Engineering, University of Palermo, Viale delle Scienze, Edificio 6, Palermo 90128, Italy
| | | | | | | | | | - Silvia Zanettini
- due2lab s.r.l., Via Paolo Borsellino 2, Scandiano, Reggio Emilia 42019, Italy
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19
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Buttacavoli A, Principato F, Gerardi G, Bettelli M, Sarzi Amadè N, Zappettini A, Seller P, Veale MC, Fox O, Sawhney K, Abbene L. Room-temperature performance of 3 mm-thick cadmium-zinc-telluride pixel detectors with sub-millimetre pixelization. JOURNAL OF SYNCHROTRON RADIATION 2020; 27:1180-1189. [PMID: 32876592 DOI: 10.1107/s1600577520008942] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
Cadmium-zinc-telluride (CZT) pixel detectors represent a consolidated choice for the development of room-temperature spectroscopic X-ray imagers, finding important applications in medical imaging, often as detection modules of a variety of new SPECT and CT systems. Detectors with 3-5 mm thicknesses are able to efficiently detect X-rays up to 140 keV giving reasonable room-temperature energy resolution. In this work, the room-temperature performance of 3 mm-thick CZT pixel detectors, recently developed at IMEM/CNR of Parma (Italy), is presented. Sub-millimetre detector arrays with pixel pitch less than 500 µm were fabricated. The detectors are characterized by good room-temperature performance even at high bias voltage operation (6000 V cm-1), with energy resolutions (FWHM) of 3% (1.8 keV) and 1.6% (2 keV) at 59.5 keV and 122.1 keV, respectively. Charge-sharing investigations were performed with both uncollimated and collimated synchrotron X-ray beams with particular attention to recovering the charge losses at the inter-pixel gap region. High rate measurements demonstrated the absence of high-flux radiation-induced polarization phenomena up to 25 × 106 photons mm-2 s-1.
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Affiliation(s)
- Antonino Buttacavoli
- Department of Physics and Chemistry (DiFC) - Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | - Fabio Principato
- Department of Physics and Chemistry (DiFC) - Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | - Gaetano Gerardi
- Department of Physics and Chemistry (DiFC) - Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | | | | | | | - Paul Seller
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX, United Kingdom
| | - Matthew C Veale
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX, United Kingdom
| | - Oliver Fox
- B16 Beamline, Diamond Light Source, Fermi Avenue, Didcot, United Kingdom
| | - Kawal Sawhney
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX, United Kingdom
| | - Leonardo Abbene
- Department of Physics and Chemistry (DiFC) - Emilio Segrè, University of Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
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