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arXiv · 2202.10990

Surface recombination and space-charge-limited photocurrent-voltage (PC-V) measurements in (Cd,Mn)Te samples. Kinetics of photocurrent (PC)

Andrzej Mycielski·Dominika M. Kochanowska·Aneta Wardak·Krzysztof Goscinski·Michal Szot·Witold Dobrowolski·Gabriela Janusz·Malgorzata Gorska·Lukasz Janiak·Wieslaw Czarnacki·Lukasz Swiderski·Joanna Iwanowska-Hanke·Marek Moszynski
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Abstract

Photocurrent-voltage characteristic (PC-V) is a method of determining the critical parameter in X-ray and gamma-ray detector plates, i.e., the carrier mobility - lifetime product, mt. We show on the (Cd,Mn)Te samples that the measurement results depend strongly on the surface treatment and the charge space distribution. The PC-V characteristics obtained for hv > Eg and hv ~ Eg indicated that etching with 20% HCl caused an appearance of a significant concentration of very shallow surface traps at the (Cd,Mn)Te sample surface. These traps seriously changed the measurements of PC-V characteristics and PC kinetics. We also noticed a small contribution of holes to photoconductivity in the PC kinetics. The PC-V characteristics measurements for hv > Eg may test the detector plate surface quality.

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Andrzej Mycielski, Dominika M. Kochanowska, Aneta Wardak, Krzysztof Goscinski, Michal Szot, Witold Dobrowolski, Gabriela Janusz, Malgorzata Gorska, Lukasz Janiak, Wieslaw Czarnacki, Lukasz Swiderski, Joanna Iwanowska-Hanke, Marek Moszynski. 2022-02-22. Surface recombination and space-charge-limited photocurrent-voltage (PC-V) measurements in (Cd,Mn)Te samples. Kinetics of photocurrent (PC). https://doi.org/10.3390/s22082941

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