The effect of low pressure chemical vapor deposition of silicon nitride on the electronic interface properties of oxidized silicon wafers

The effect of LPCVD Si(3)N(4)film deposition on oxidized Si wafers, to form Si3N4/SiO2/ Si stacks, is studied using capacitance-voltage and carrier lifetime measurements. The deposition of a nitride film leads to an increase in the density of defects at the Si-SiO2 interface, with the increase being greater the thinner the oxide. However, even the presence of a very thin intermediate oxide results in a dramatic improvement in interface properties compared to the direct deposition of the Si3N4 film on A The interface degradation occurs in the initial stages of nitride film deposition and appears to be largely the result of increased interfacial stress. Subsequent thermal treatments do not result in significant further degradation of the Si-SiO2 interface (except for a loss of hydrogen), again in contrast to the case where the nitride films is deposited onto Si. Copyright (C) 2007 John Wiley & Sons, Ltd.