Nucleation and growth of CVD Si thin films: AFM, SE and TEM analysis

The nucleation and growth of in situ doped, LPCVD silicon films was analyzed using atomic force microscopy, variable-angle spectroscopic ellipsometry, and transmission electron microscopy. The RMS surface roughness initially increases from 0.5 to 5.7 nm with increasing deposition times and then rapidly decreases to 0.5 nm for longer times. Ellipsometry data was modeled using two layers where the top layer consists of a mixture of amorphous Si plus voids and the bottom layer is a continuous amorphous Si layer. Cross-section TEM reveals the nuclei size and structure for these silicon films and confirms the results of the other techniques.