Interaction between <i>n</i>-type amorphous hydrogenated silicon films and metal electrodes

Abstract

The interactions of Al and NiCr electrodes with hydrogenated n-type amorphous silicon films have been investigated in a temperature range of 100–350 °C. It was found that pits were produced in the a-Si films at temperatures above 170 °C in the case of Al electrodes, while they were not observed in the case of NiCr electrodes even if heat-treated at a temperature of 350 °C. From the Auger electron spectroscopy measurements, it was shown that a marked interdiffusion of Al and Si occurs. The sheet resistance of the a-Si films began to increase at temperatures above 170 °C. The contact resistivity between the a-Si films and Al electrodes could not be determined in the case of a-Si films with usual low conductivity. For the specimens with high conductivity [σ∼1(Ω cm)−1], the value of about 1×10−3Ω cm2 was obtained.