Patent ID: 6054354
Filing Date: 2000-04-25
Classification: H01L

Abstract:
A method for forming field effect transistors (FETs) on a wafer comprising the steps of:a) forming a gate dielectric layer on a semiconductor layer;b) forming a gate layer on said gate dielectric layer;c) blocking at least one area of said gate layer, said blocked area including a first FET;d) forming at least a second FET in areas not blocked;e) doping said second FET; andf) unblocking said first FET, and implanting a dopant into a gate and source/drain regions of said first FET, said gate being depleted at said gate dielectric layer and said source/drain regions being depleted at said gate dielectric layer, such that said first FET has a thicker effective gate dielectric than said second FET,wherein said second FET is subjected to only one doping step, said one doping step corresponding to step (e).