摘要 |
A high density metal gate metal-oxide semiconductor fabrication process to selectively and locally oxidize specific regions of a wafer without increasing the numbers of mask, so as to separately control the thickness of the oxide at the gate, P+ zones and N+ zones, the process including the step of forming a first tye trap zone, the step of forming a shielding layer consisting of an oxide pad and a nitride layer, and the step of forming an oxide layer and removing the nitride layer but the oxide pad to be left before the growing of an insulative oxide layer.
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