摘要 |
A method of forming a CMOS transistor which comprises providing a partially fabricated CMOS structure having a p-type region wherein NMOS devices will be fabricated and an n-type region wherein PMOS devices will be fabricated, a separate pattern defining each region, a thin gate oxide layer in each window and a thin polysilicon gate layer having a thickness up to 3200 ANGSTROM over the thin gate oxide layer having a thickness up to 90 ANGSTROM . A layer of glass having a boron doping species therein, preferably borosilicate glass, is deposited over the polysilicon gate layer disposed over the the n-type region. The portion of the polysilicon gate layer disposed defining the p-type region is then doped n-type, preferably by implanting phosphorus, and the structure is heated to cause boron to diffuse from the layer of glass into the polysilicon gate layer over the n-type region. The layer of glass of glass is removed and fabrication of the CMOS device is then completed in standard manner.
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