Patent ID: 6534350
Filing Date: 2003-03-18
Classification: H01L

Abstract:
A method for activating dopant ions in a polysilicon thin film transistor (TFT) comprising the steps of:providing a substrate; forming a polysilicon island on said substrate; depositing an insulating material layer overlying said polysilicon island; depositing a photoresist layer on top of said insulating material layer without contacting said polysilicon island and patterning said photoresist layer to overlie only a channel portion in said polysilicon island; etching away, optionally, said insulating material layer except an area covered by said patterned photoresist layer; doping by implanting N+ dopant ions in said polysilicon island and activating the implanted dopant ions by laser irradiation through said remaining insulating material layer situated on top; forming a gate insulator layer on top of said polysilicon island; and forming a metal gate on top of said gate insulator layer after said activation step for said polysilicon island.