Jl. Autran et al., A COMPARISON OF SI-SIO2 INTERFACE-TRAP PROPERTIES IN THIN-FILM TRANSISTORS WITH THERMAL AND PLASMA-NITRIDED OXIDES, Journal of non-crystalline solids, 187, 1995, pp. 374-379
In this work, electrical properties of the Si-SiO2 interface have been
investigated in terms of interface-trap parameters (emission time, ca
pture cross-section, state density) by standard and three-level charge
pumping techniques in n-channel thin-film (8 nm) metal-oxide-semicond
uctor field-effect transistors. Some of the devices have been nitrided
in an ammonia plasma reactor and reoxidized in oxygen. For nitrided d
evices, a significant decrease of interface state density, D-it, has b
een observed as compared with pure oxide devices. This reduction clear
ly corresponds to both an uniform decrease of D-it over the silicon ba
nd gap and a decrease of a D-it peak in the upper part of the band gap
. The evolution of capture cross-sections has been also monitored and
found to significantly vary for electron traps. This substantial chang
e in electron interface-trap properties could be at the origin of the
augmentation of the high field transconductance: observed for these n-
channel devices after such a nitridation process.