SINGLE CHAMBER CVD PROCESS FOR THIN FILM TRANSISTOR

PROBLEM TO BE SOLVED: To provide an improvement method for depositing an intrinsic amorphous silicon layer and a doped amorphous silicon layer sequentially on a substrate in the same CVD chamber without raising a contamination problem. SOLUTION: The method is carried out by sequentially depositing a layer of dielectric insulating material on the substrate in the same CVD chamber by means of a first deposition operation prior to the deposition of the intrinsic amorphous silicon layer. The insulating material deposited on the TFT substrate has a thickness such that residual insulating material sufficient to cover the residual dopant left on the chamber walls by the deposition process on the substrate carried out previously is coated on the chamber walls. This provides a clean environment for the next deposition process of depositing the intrinsic amorphous silicon layer on the substrate in the same CVD chamber. COPYRIGHT: (C)2007,JPO&INPIT