Very Low Temperature Deposition of Polycrystalline Si Films Fabricated by Hydrogen Dilution with Electron Cyclotron Resonance Chemical Vapor Deposition

Characteristics of polycrystalline silicon films deposited both on SiO2 and Corning 7059 glass substrates are presented in this paper. The silicon films were deposited by a hydrogen dilution method using electron cyclotron resonance chemical vapor deposition at 250° C without any thermal or laser annealing. The hydrogen dilution ratio was between 90% and 99%. The geometric configuration and surface morphology of polycrystalline silicon films were studied by atomic force microscopy. The largest grain size of the deposited silicon films, identified by plan-view transmission electron microscopy dark-field imaging, was about 1 µ m. From Raman spectrum, the crystalline fraction of polycrystalline silicon films was identified to be nearly 100%. The polycrystalline silicon was found to be preferentially <111>- and <110>-oriented, from the X-ray diffraction pattern.