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Title: Kinetics of photoconductivity in ZnSe crystals upon photoexcitation of deep centers

Abstract

It has long been known that investigation of the spectral characteristics of photoconductivity (PC) in wide-band-gap semiconductors does not provide full information on the position of photosensitive centers in the forbidden band. The broad spectrum of intrinsic and impurity PC consists of several overlapping bands. In the long-wavelength region, impurity photoeffect is superimposed over the falling-off spectrum of intrinsic PC. In addition, measurements of steady-state PC are incapable of revealing photoinsensitive recombination and trapping centers. Those levels that were not excited prior to illumination of the semiconductor may provide no contribution to PC and may appear either photoinsensitive or indistinguishable from dominant channels of recombination and trapping on other centers. Preliminary excitation may alter the state of these levels to such a degree that they will show up as a spike in the PC relaxation curve. In this paper, we report kinetic studies of the PC and the effective cross section for photon capture (CSPC) in the photosensitivity range of zinc selenide single crystals containing trace impurities.

Authors:
; ;  [1]
  1. Moldova State Univ., Kishinev (Monaco)
Publication Date:
OSTI Identifier:
244230
Resource Type:
Journal Article
Resource Relation:
Journal Name: Inorganic Materials; Journal Volume: 31; Journal Issue: 10; Other Information: PBD: Oct 1995; TN: Translated from Neorganicheskie Materialy; 31: No. 10, 1296-1298(1995)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ZINC SELENIDES; PHOTOCONDUCTIVITY; DOPED MATERIALS; EXCITATION; PHOTOSENSITIVITY; RELAXATION

Citation Formats

Bruk, L.I., Gorya, O.S., and Korotkov, V.A. Kinetics of photoconductivity in ZnSe crystals upon photoexcitation of deep centers. United States: N. p., 1995. Web.
Bruk, L.I., Gorya, O.S., & Korotkov, V.A. Kinetics of photoconductivity in ZnSe crystals upon photoexcitation of deep centers. United States.
Bruk, L.I., Gorya, O.S., and Korotkov, V.A. Sun . "Kinetics of photoconductivity in ZnSe crystals upon photoexcitation of deep centers". United States. doi:.
@article{osti_244230,
title = {Kinetics of photoconductivity in ZnSe crystals upon photoexcitation of deep centers},
author = {Bruk, L.I. and Gorya, O.S. and Korotkov, V.A.},
abstractNote = {It has long been known that investigation of the spectral characteristics of photoconductivity (PC) in wide-band-gap semiconductors does not provide full information on the position of photosensitive centers in the forbidden band. The broad spectrum of intrinsic and impurity PC consists of several overlapping bands. In the long-wavelength region, impurity photoeffect is superimposed over the falling-off spectrum of intrinsic PC. In addition, measurements of steady-state PC are incapable of revealing photoinsensitive recombination and trapping centers. Those levels that were not excited prior to illumination of the semiconductor may provide no contribution to PC and may appear either photoinsensitive or indistinguishable from dominant channels of recombination and trapping on other centers. Preliminary excitation may alter the state of these levels to such a degree that they will show up as a spike in the PC relaxation curve. In this paper, we report kinetic studies of the PC and the effective cross section for photon capture (CSPC) in the photosensitivity range of zinc selenide single crystals containing trace impurities.},
doi = {},
journal = {Inorganic Materials},
number = 10,
volume = 31,
place = {United States},
year = {Sun Oct 01 00:00:00 EDT 1995},
month = {Sun Oct 01 00:00:00 EDT 1995}
}
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