Illumination with Ultraviolet Light of MOS Capacitors

Abstract

UV illumination of MOS capacitors induces an increase of the surface state density of the SiSiO2 interface. This increase depends on the number of charges which cross the structure during the illumination. Bias‐temperature treatment are performed on preilluminated samples and an annihilation of the created surface states is observed depending on the bias. The results are explained by a qualitative model in which a breaking of SiH or SiOH bonds of the SiSiO2 heterojunction zone occurs during the illumination and a restructuration of these broken bonds occurs during the bias‐temperature anneal.

Surface-state generation on MOS capacitors irradiated with UV light and electrons

“…Since the photocurrents are much larger for negative gate bias than for positive gate bias, we consider that the charge Q passing through the oxide is the most relevant physical parameter [ 2 ] . This charge is determined by integrating the photocurrent i ( t ) where t is the time of illumination.…”

“…The main features of the experimental techniques: sample preparation, electrical measurements, illumination procedures have been described in our preceding paper [ 2 ] . The electron irradiation conditions are also described elsewhere [3].…”