Fabrication of high mobility poly-Si TFT by cat-CVD method

摘要

Polycrystalline silicon (Poly-Si) thin films transistor (TFT) is prepared by Catalytic Vapor Deposition (Cat-CVD) method. In this method, when the crystalline fraction of poly-Si becomes high, the contamination such as oxygen, which degrades the TFT characteristics, used to be frequently observed. In this study, we succeeded to obtain the high crystalline poly-Si films with low oxygen contamination. From the relation between the TFT mobility and the oxygen concentration of poly-Si films, it is concluded that high mobility poly-Si TFT with more than 10 cm{sup}2/Vs can be obtained, if the poly-Si film with high crystalline fraction over 90 has low oxygen concentration less than 10{sup}19 cm{sup}(-3) order.