Patent ID: 6905976
Filing Date: 2005-06-14
Classification: H01L,Y10S

Abstract:
1. A method of making a metal oxide semiconductor field effect transistor (MOSFET) having a notched gate structure, comprising: defining an active area of a substrate; forming a gate dielectric on said active area; forming a first gate conductor layer of polysilicon on said gate dielectric; and forming a second gate conductor layer of silicon germanium (SiGe) over said first pate conductor layer; forming a third gate conductor layer of polysilicon over said SiGe lever; forming a masking layer over said third gate conductor layer; patterning said first, second and third gate conductor layers by vertical etching, stopping on said gate dielectric; thereafter, laterally etching said first gate conductor layer such that said SiGe layer is broader than and overhangs said first gate conductor layer; and completing said transistor.