| 摘要 |
PURPOSE:To obtain a TFT excellent in driving stability, by constituting an oxide film and a second polysilicon layer formed in order on a first polysilicon layer formed on a substrate, and making up the second polysilicon layer of P-doped polysilicon. CONSTITUTION:On a substrate 1, a first polysilicon layer 2 is formed by atmospheric pressure CVD (APCVD) method, low pressure CVD (LPCVD) method, etc. Thereon, a gate oxide film (SiO2)3 is formed, on which a second polysilicon layer 4 is formed. On the second polysilicon layer 4, is formed a surface protecting layer 5 of SiO2 or the like formed by CVD method. In this layer constitution, the second polysilicon layer 4 is required to be doped polysilicon containing P atom, which acts as a getter material for maveable ion such as Na<+> ion. |
