METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

A method for manufacturing a semiconductor device, the semiconductor device includes two MOSFETs with opposite type formed on a semiconductor substrate. The method comprises: defining active regions for each MOSFET in the semiconductor substrate (101); forming an interfacial oxide layer (103) on the surface of the semiconductor substrate (101); forming a high-K gate dielectric layer (104) on the interfacial oxide layer (103); forming a metal gate layer (105) on the high-K gate dielectric layer (104); implanting dopant ions into the metal gate layer (105); forming a polysilicon layer (109) on the metal gate layer (105); patterning the polysilicon layer (109), the metal gate layer (105), the high-K gate dielectric layer (104) and the interfacial oxide layer (103) into a gate stack layer; forming gate sidewall spacers (110a, 110b) around the gate stack layer; and forming source/drain regions (111a, 111b). By annealing the source/drain areas (111a, 111b), the dopant ions of the metal gate (105) are accumulated at the interface and electric dipoles with appropriate polarity are generated, realizing the effective work function modulation for the metal gate of the different-type MOSFETs, respectively.