Analysis of dielectric function of silicon films with spectroscopic ellipsometry

Spectroscopic ellipsometry (SE), a common method for films optic parameter test, owns several advantages, such as good sensitivity, excellent precision and scatheless to the samples. Firstly, the theory model of effective medium approximation(EMA) is introduced, then a computer theory fitting between EMA model and the SE measure results is operated. It indicates that the calculated results are consistent with the SE data perfectly when we assume the silicon film as a mixture of amorphous, polycrystalline and voids, and then the microstructure information of samples is obtained.