The behaviour of minority carriers in thermally stimulated studies of the SiSiO2 interface

Abstract

Features of thermally stimulated charge release (TSCR) currents from centers in the transition layer of the SiSiO2 interface in the temperature range from 6 to 20 K are investigated. It is shown that for a correct determination of the shallow acceptor center density in the n‐type semiconductor one should control injection abilities of the substrate contact. Filling of the acceptor states in the interface should be performed at proper temperatures when hole injection into the semiconductor bulk takes place. Different situations are modelled using two types of substrate contacts: (i) made by deposition of the Al layer on the back side of a wafer; (ii) created by rubbing the back side with GaZn eutectic. A method to determine the concentration of deep acceptor centers in the semiconductor bulk based on TSCR current registration after different modes of trap filling is proposed.