Effect of point defects trapping characteristics on mobility-lifetime (μτ) product in CdZnTe crystals

Formation of Grown-In Nitrogen Vacancies and Interstitials in Highly Mg-Doped Ammonothermal GaN

“…Since the μτ product determines the quality of semiconductor material in terms of its application for the fabrication of various kinds of sensors, used as photodetectors, X-ray detectors, and radiation detectors, the results shown in Figure 2 b are of practical importance [ 31 , 35 ]. They demonstrate that by increasing the doping level in SI AT-GaN:Mg crystals, it is possible to obtain the material suitable for making unique detectors operating at 600 K. In view of the fact that above 300 K the mobility of charge carriers decreases with temperature due to the lattice scattering, the observed in Figure 2 b rise in the μτ values as a function of temperature can only result from the strong increase in the excess charge carriers lifetime [ 35 ]. The lifetime strongly depends on the properties and concentrations of deep-level defects acting as the recombination centers and the ionization levels of the most efficient recombination centers are located in the vicinity of the middle of the bandgap [ 35 ].…”

“…They demonstrate that by increasing the doping level in SI AT-GaN:Mg crystals, it is possible to obtain the material suitable for making unique detectors operating at 600 K. In view of the fact that above 300 K the mobility of charge carriers decreases with temperature due to the lattice scattering, the observed in Figure 2 b rise in the μτ values as a function of temperature can only result from the strong increase in the excess charge carriers lifetime [ 35 ]. The lifetime strongly depends on the properties and concentrations of deep-level defects acting as the recombination centers and the ionization levels of the most efficient recombination centers are located in the vicinity of the middle of the bandgap [ 35 ]. According to the results shown in Figure 2 a, the efficient recombination centers are likely to be present only in the material with the lower [Mg] (sample #1).…”

“…The observed changes in the lifetime against temperature reflect the changes in the charge carrier recombination rate, being equal to the lifetime reciprocal. In other words, for both kinds of materials, the recombination rate decreases with temperature, and in the case of deeper recombination centers (sample #1), the decrease is slower than for the centers whose ionization levels are located closer to the VBM or CBM [ 35 ]. In view of the SRH recombination model, proposed by Shockley, Read, and Hall [ 36 , 37 ], the recombination takes place when an electron from the conduction band is captured by the empty defect level and then a hole from the valence band is captured by an electron occupying this level.…”

Effect of CZT Powder Burying CZT Crystal on Annealing in Cd Atmosphere

“…Due to the inevitable introduction of volume defects (Te inclusions) [5] and deep-level defects (V Cd , Te Cd , etc.). [6][7][8] These volume defects or point defects may become trap centers, DOI: 10.1002/crat.202300054 causing distortion of the electric field in the crystal, deteriorating the carrier transport ability near itself, and seriously deteriorating the performance of the detector when the concentration reaches a higher concentration. [9,10] Its formation is mainly due to the fact that when the crystal is in the cooling stage, the Terich phase shrinks, the solid solubility of Te decreases, and the supersaturated Te precipitates out to form Te inclusions, which cannot be avoided during the crystal growth process.…”

Formation and characterization of a CuPt-A type ordered structure in cadmium zinc telluride single crystals

“…10 Such above-mentioned excellent performance is closely related to the phase composition of the single crystals grown by the melting method. Various types of defects with different scales, including anti-site defects, 11,12 extended dislocations, 13–15 and precipitation/inclusions, 16,17 together with their effects on the electrical and optical properties have been extensively studied in various CdTe-related compounds. In general, the above-mentioned defects are harmful to the photoelectric properties of the material, because the existence of these defects destroys the periodicity of the crystal lattice and hinders the transport of carriers.…”