Influence of Nanocrystalline Silicon Conductivity on the Structural and Optical Properties of Porous Silicon

Kadyrzhan Dikhanbayev

Isa Zharekeshev

Azamat Zhambyl

Yerulan SagidoldaEmail

Zhansaya Baspakova

Bakyt Khaniyev

Nursultan Meirambekuly

Yeldos Kozhagulov

Shyryn ZhumatovaEmail

Al-Farabi Kazakh National University, Al-Farabi Ave. 71, Almaty, 050040, Kazakhstan

Abstract

Silicon substrates with p-n junction were layer-by-layer etched along the depth of the n-layer by the method of electrochemical anodization on the surface; the obtained porous silicon films were analyzed by means of voltammetric response, reflection spectra and photoluminescence spectra as a function of the conductivity of the gradient layer along the depth of the p-n junction. It is shown that current flow across the thin-film layer, in particular, with the increase of the layer resistance along the etching depth there appears a region of space charge associated with the depletion of charge in the vicinity of the p-n junction and an increase in the forward current-voltage characteristics, after which current rectification begins.