A spectroscopic ellipsometry study of the growth and microstructure of glow-discharge amorphous and microcrystalline silicon films

Spectroscopic ellipsometry (SE) has been used to study the surface, microstructure, and optical properties of glow-discharge deposited amorphous and microcrystalline silicon films. The SE data has been analyzed using multilayer models, effective medium approximation, and linear regression analysis. The studies have shown that with increasing rf power and silane dilution, a gradual transition from good (dense) a-Si:H to a spongy material with a large density deficit, and then to a microcrystalline material is obtained. A quantitative analysis of the microstructure of a-Si:H films with growth parameters has been carried out. Combined with infrared and x-ray diffraction measurements, the results have been explained in terms of a nucleation and growth model.