STRUCTURAL PROPERTIES INVESTIGATION ON MICROCRYSTALLINE SILICON FILMS DEPOSITED WITH VHF-PECVD TECHNIQUE

摘要

Raman scattering spectroscopy and scanning electron microscopy (SEM) techniques were used to determine the structural properties of two typical series of microcrystalline silicon (mu c-Si:H) films deposited at different VHF plasma power and different working gas pressure by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) technique. Raman spectra measurements show that both crystalline volume fraction Xc and average grain size d of /Ac-Si: H films are strongly affected by the two deposition conditions and are more sensitive to working gas pressure than VHF plasma power. SEM characterizations have further confirmed that VHF plasma power and working gas pressure could clearly enhance the surface roughness of xc-Si: H films ascribing to polymerization reactions, which is also more sensitive to working gas pressure than VHF plasma power.