Journal of Applied Science and Engineering

Published by Tamkang University Press


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R.G. Ikramov, M.A. Nuriddinova, Kh. A. MuminovThis email address is being protected from spambots. You need JavaScript enabled to view it., O.T. HolmirzaeV, and B.Q. Sultonov

Namangan Engineering and Technology Institute, 7 Kosonsoy Street, Namangan 160115, Uzbekistan


Received: July 1, 2022
Accepted: September 20, 2022
Publication Date: November 2, 2022

 Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

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The region of exponential absorption of the spectra of amorphous semiconductors is theoretically investigated using the Davis-Mott approximation method from the Kubo-Greenwood formula. Analytical expressions for the partial absorption spectra for the exponential region are derived from two different types of the Kubo-Greenwood formula. A new method is presented for calculating the distribution density of electronic states in the tails of the conduction band of amorphous semiconductors based on the analytical expression for experimental exponential absorption spectra. The density of electronic states in the tail of the conduction band of an amorphous solid selenium-sulfur alloy is determined from the experimental exponential absorption spectrum of this material.

Keywords: exponential region of absorption spectra, partial absorption spectra, tail of the conduction band, distribution of the density of electronic states


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