Home Detector Organization Blog News Thesis

CZT Thesis

The CZT Thesis section features research theses focused on Cadmium Zinc Telluride (CZT) materials and their applications
Enhanced performance CdZnTe single crystal with few surface damages via solution based annealing
Date: June 30, 2025 | Author: Siwei Tang | Hits: 31
In this study, heat treatments were employed using a CdCl2 solution as the annealing medium to investigate the evolution of internal defects and photoelectric properties of CdZnTe crystals. It was observed that CdCl2 crystals formed on the surface of the annealed crystals, and their size increased exponentially with prolonged annealing time. It could be a medium for Cl transport. The liquid-phase annealing process was found to be gentle, resulting in minimal damage and the absence of large def ...
Advancements in Iso-Diameter seeded growth of CdZnTe crystals: A numerical modeling approach and applications in liquid phase Epitaxy
Date: June 30, 2025 | Author: Chao Xu | Hits: 30
CdZnTe (CZT) is the preferred material for HgCdTe (MCT) infrared detectors and room temperature nuclear-radiation detector applications. However, their widespread application is hindered by the low yield, attributed to intrinsic thermophysical properties like extremely low thermal conductivity and stacking fault energy, complicating the growth of large-volume crystals. Based on steady-state computer numerical modeling simulation, this paper examines the impact of seed size variations (from 15 ...
The effect of Te solution volume on the growth of CdZnTe crystals by Traveling Heater Method
Date: June 29, 2025 | Author: Jijun Zhang | Hits: 11
Nowadays, Traveling Heater Method (THM) is demonstrated to be one of the most promising ways to grow high-quality CdZnTe (CZT) crystals. The THM is essentially a melt-solution growth method, in which the CZT solute diffuses from the dissolution interface to the growth interface in the Te solution and deposits on the CZT seed. In this work, the effects of Te solution volumes on the structure of CZT solute, growth interface, defects and electrical properties of CZT crystals grown by THM were inv ...
Growth of high quality CdZnTe (133) epilayers on GaAs (211) substrate with Zn1−xCdxTe-ZnTe buffer layer by close spaced sublimation
Date: June 29, 2025 | Author: Gangqiang Zha | Hits: 72
The Cd0.96Zn0.04Te (211) crystal is widely recognized as the optimal substrate for epitaxy growth of HgCdTe material. However, its further application is significantly hindered by size and cost limitations. CdZnTe films grown on GaAs substrates by close spaced sublimation may present a promising substrate for epitaxial HgCdTe. In this work, we successfully prepared high quality CdZnTe (133) films on GaAs (211) substrate. The results of scanning transmission electron microscope and selected-are ...
Controllable convex interface shape during vertical gradient freeze (VGF) growth of CdZnTe crystal
Date: June 28, 2025 | Author: Shangshu Li | Hits: 27
A convex growth interface shape is desired but is usually hard to form during the Bridgman process of CdZnTe crystal due to its low thermal conductivity. In this work, the convex interface shape was first analyzed and the mathematical criterion was determined. Theoretical analysis indicates that a convex interface can form when the derivative of axial temperature gradient () near the interface is negative. The temperature profiles were then proposed according to the theoretical results, and co ...
CdZnTe semiconductor-based dual imager combining collimatorless and Compton imaging- Monte Carlo simulation
Date: June 28, 2025 | Author: Wonho Lee | Hits: 23
Compton imaging excels at visualizing gamma rays in the range of several hundred kiloelectronvolts to several megaelectronvolts. However, this technique has limitations in the imaging of low-energy gamma rays. In contrast, collimatorless imaging technique determines the location of a source by analyzing the distribution of interactions. Because the collimatorless imaging technique excels at imaging low-energy gamma rays that are easily shielded by detector components, it can compensate for the ...
Optimized substrate temperature for high-quality CdZnTe epitaxial film in X-ray flat panel detectors
Date: June 27, 2025 | Author: Tingting Tan | Hits: 30
Cadmium zinc telluride (CdZnTe or CZT) materials, favored for their physical superiority in optoelectronic applications, can be efficiently produced as large-area epitaxial film via close space sublimation (CSS), enhancing potential in flat-panel detector imaging. However, the application of CdZnTe epitaxial film in medical imaging equipment is limited by their lower resistivity, prolonged response times, and diminished sensitivity. By elevating the substrate temperature, we enhanced the numbe ...
Effect of abrasive particle size and oxidant concentration on CdZnTe crystal properties during CMP proces
Date: June 27, 2025 | Author: Jijun Zhang | Hits: 63
Cadmium Zinc Telluride (CZT) crystals are widely regarded as the optimal semiconductor materials for producing room temperature high-energy radiation detectors. The goal of polishing is to enhance the quality of the crystal surface. This paper adopts a three-step polishing process, where the first two steps involve mechanical polishing with Al2O3 polishing slurries of different particle sizes. The third step employs the chemical mechanical polishing (CMP) of CZT crystals with a polishing slurr ...
Improvement of radiation detection performance of detector prepared by CdZnTe epitaxial single crystal
Date: June 26, 2025 | Author: Yingrui Li | Hits: 50
The radiation detection performance of CZT epitaxial single crystal grown by the Close Space Sublimation (CSS) method is hindered by inherent defects. However, significant improvement in this work is achieved through annealing in a Te2 atmosphere. The saturation channel value of the total energy peak of the detector for 241Am α-particles has shown a substantial increase from 1900 to 6000, resulting in a notable enhancement of the carrier collection efficiency. After annealing, the detector&ap ...
Microstructure evolution of CdZnTe crystals irradiated by heavy ions
Date: June 26, 2025 | Author: Lingyan Xu | Hits: 15
Consideration of irradiation effects is important for in-orbit operation and radiation protection in aerospace applications. The configuration of irradiation defects and their impact on deteriorating the carrier transport properties of CZT crystals need to be clarified. In this study, the microdefect evolution mechanism of CdZnTe (CZT) crystals under 10 MeV Chlorine (Cl) ion irradiation at flux of 1 × 1010∼1 × 1012 n·cm−2 are investigated. The stacking faults first appear in the CZT cry ...
Spatial variation of the low-temperature micro-photoluminescence of THM-grown CdZnTeSe
Date: June 25, 2025 | Author: Utpal Roy | Hits: 8
The quaternary compound CdZnTeSe (CZTS) has emerged as a next-generation detector material. Unlike CdZnTe (CZT), CZTS has the distinct advantages of little or no sub-grain boundary networks and a much lower concentration of Te inclusions, plus better compositional homogeneity. Thus, the material is expected to offer better spatial charge-transport homogeneity compared to CZT. However, an inhomogeneous distribution of point defects in both CZT and CZTS, such as Cd vacancies and residual impurit ...
Radiation attenuation parameters and intrinsic efficiency of a few semiconductor crystals for radiation detection applications
Date: June 25, 2025 | Author: S.G. Bubbly | Hits: 30
This study investigates the effectiveness of nine inorganic semiconductor crystals − LiGaSe2, LiInSe2, CsHgInS3, SnS, GaTe, BiI3, Sb2Te3, Tl4CdI6, and TlBr − for radiation detection applications based on photon and charged particle (electrons, protons, and heavy ions) interaction parameters. Mass attenuation coefficient (μ/ρ), half value layer (HVL), relaxation length (λ), effective atomic number (Zeff), electron density (Neff), equivalent atomic number (Zeq), and exposure buildup facto ...
A gamma-ray imaging method for multiple radionuclides and low-activity radioactive sources
Date: June 24, 2025 | Author: Donghai Fan | Hits: 30
Gamma-ray coded-aperture imaging technology has important applications in the fields of nuclear security, isolated source detection, and the decommissioning of nuclear facilities. However, artifacts can reduce the quality of reconstructed images and affect the identification of the intensity and location of radioactive sources. In this paper, a gamma-ray coded-aperture imaging method based on primitive and reversed coded functions (PRCF) was proposed to reduce imaging artifacts. Building on th ...
Enhanced photoelectrochemistry properties of CdZnTeSe thin films
Date: June 24, 2025 | Author: Meng Cao | Hits: 11
CdZnTe (CZT), as an optimum absorption layer, has many attractive characteristics for photoelectrochemical (PEC) water splitting, such as tunable band gaps (1.45–2.26 eV) and high absorption coefficient (≥104 cm−1). The addition of Se into CZT was found to be very effective in arresting the formation of sub-grain boundaries, improving compositional homogeneity. In this paper, CZT films were deposited on fluorine-doped tin oxide-coated (FTO) substrates by close-spaced sublimation method. ...
Bias-induced polarization effect in Cd1-xZnxTe and Cd1-yMnyTe detectors
Date: June 23, 2025 | Author: O. Amzallag | Hits: 81
The study aims to compare the evolution of the electric field profiles in CdZnTe and CdMnTe detectors from the initial biasing activation until the steady state is reached (referred here as polarization effect). The crystals are grown by the same method, so the comparison emphasizes the difference between Zn- and Mn-based traps. The results demonstrate that the settling times in the CdZnTe and CdMnTe devices differ, but both are on the scale of hours. The effect of these, rather moderate varia ...
Structural, defect, and photoelectric characterization of CdTe-based single crystals grown by a vertical Bridgman method
Date: June 23, 2025 | Author: Pengfei Yu | Hits: 28
This study presents a comparative characterization of CdZnTe, CdMnTe, and CdMgTe single crystals, grown via a modified vertical Bridgman method, focusing on their structural, defect, optical, and electrical properties for room-temperature radiation detection applications. XRD analysis confirmed the sphalerite structure of all three crystals, with distinct preferred orientations influenced by spontaneous nucleation. CdMgTe crystal featured a lower density of Te inclusions (approximately 103 cm ...
Two-step passivation by K2S2O8 and NH4F-H2O2 solutions for improving the performance of CdZnTe detectors
Date: June 22, 2025 | Author: Jinbin Wang | Hits: 45
Passivation plays a crucial role in surface treatment, which could generate an oxide layer that significantly decreases the surface leakage current of Cadmium zinc telluride (CdZnTe, CZT) detectors and enhancing their final performance. However, existing passivation methods are limited by the unevenness of the oxide layer and insufficient reduction in surface leakage current. In this paper, a novel two-step passivation method for CdZnTe is proposed, in which the first step uses potassium persu ...
The effect of low energy high-dose X-ray irradiation on the performance of CdZnTe detector
Date: June 22, 2025 | Author: Wanqi Jie | Hits: 43
The paper investigated the irradiation damage of CZT detectors caused by high flux an X-ray from X-ray tube operated at a tube voltage of 140 kV and an accumulated dose of 130 kGy. Deep-level transient spectroscopy (i-DLTS) was employed to characterize the defects. Four types of irradiation-induced defects were identified, corresponding to the energy levels at Ec-0.1eV, Ev+0.17eV, Ev+0.27eV and Ec-0.55eV, which are associated with the point defects, InCd+/0, VCd -/0, VCd 2−/− and TeCd 2+/+ ...
Enhancement of detection performances of cadmium zinc telluride (CdZnTe) radiation detectors through sapphire substrates
Date: June 21, 2025 | Author: Zilong Zhang | Hits: 51
Cadmium zinc telluride (CdZnTe) is a highly effective semiconductor material, renowned for its exceptional properties. In this study, we employed the close-spaced sublimation method to grow high-quality CdZnTe thick films on sapphire substrates. The effects of growth temperature on the composition, surface defects, and structural and electrical properties of CdZnTe films were examined. The investigation identified the optimal temperature conditions for the production of thick CdZnTe films of h ...
Effect of a seed layer on the properties of CdZnTe thick films prepared by close-spaced sublimation method
Date: June 21, 2025 | Author: Ke Tang | Hits: 15
In recent years, CdZnTe has attracted extensive attention due to its excellent properties. In this paper, CdZnTe thick films were prepared by close-spaced sublimation (CSS) method. An innovative method of introducing a seed layer is employed to enhance the performance of CdZnTe thick films and their devices. The effect of the seed layer on the properties of CdZnTe thick films was systematically analyzed. The results indicate that the seed layer significantly promotes the uniform distribution a ...
The effect of Al2O3 surface passivation layer prepared by ALD method on the performance of CdZnTe thick film detectors
Date: June 20, 2025 | Author: Ke Tang | Hits: 110
In this work, cadmium zinc telluride (CdZnTe) thick films were grown using close-spaced sublimation (CSS), while Al2O3 films of varying thicknesses were deposited by atomic layer deposition (ALD) as surface passivation layers. The influence of the Al2O3 surface passivation layer on the structure, surface morphology, chemical composition and electrical performance of the CdZnTe thick films was analyzed using XRD, EDS, SEM, AFM, XPS and current–voltage (I-V) characterization systems. The resul ...
High-speed electronics system with timing and amplitude signal acquisition design for multi-channel CdZnTe Array Detector
Date: June 20, 2025 | Author: Zhe Zhao | Hits: 46
This paper presents a High-Speed Electronics System with Timing and Amplitude Signal Acquisition Design for Multi-channel Cadmium Zinc Telluride (CdZnTe) Array Detector. The readout channel comprises preamplifiers, post-amplification stages, peak hold and detection circuits, a multiplexer, an analog-to-digital converter (ADC), time-to-digital converters (TDC), and calibration circuits. In circuit design, a differential voltage amplifier (DVA) is used as the preamplifier in order to achieve sim ...
Effect of interface states on capacitance-voltage characteristics of CdZnTe crystals after surface oxidation
Date: June 19, 2025 | Author: Xiaoyan Liang | Hits: 33
The interface states of TeO2/CdZnTe affects the capacitance voltage characteristics of metal oxide semiconductor (MIS) structured CdZnTe devices. Based on numerical simulations, the interface states exhibit a capacitance hump in the depletion region of the Csingle bondV curve, which is influenced by substrate doping concentration, frequency, interface state density, and energy level position. According to microstructure and component analysis by high resolution transmission electron microscope ...
Damage generation mechanism and performance degradation of CdZnTe radiation detectors in neutron radiation field
Date: June 19, 2025 | Author: Lingyan Xu | Hits: 59
Semiconductor radiation detectors used in nuclear power plants and other environments are inevitably exposed to neutron, γ-ray and other high-energy radiation, which can damage the crystal structure of semiconductors and thus degrade the detector performance. Here, we investigate the effects of neutron irradiation on the microstructure, photoelectric and radiation detection performance of CdZnTe detectors. Low-temperature photoluminescence (PL) spectra show that the dislocation related defect ...
<<
<
1
2
3
4
>
>>
Copyright © 2025 CdZnTe Association
Indexing | Sponsor | Privacy | Email: info@cdznte.com
CdZnTe Association (CdZnTe.com) is a nonprofit website dedicated to Cadmium Zinc Telluride (CZT) technology. It serves as a comprehensive platform for sharing knowledge, research advancements, and practical applications related to CZT Crystals and Detectors. The site aims to support scientists, engineers, and students by providing access to technical resources, publications, and community-driven insights, fostering collaboration and innovation within the CZT research and development community.