Patent ID: 6620656
Filing Date: 2003-09-16
Classification: H01L

Abstract:
A method of making a semiconductor device, comprising:providing a substrate having a semiconductor layer and an insulating layer, wherein the semiconductor layer overlies the insulating layer and comprises an active area with a top surface; doping the active area to a first conductivity type; forming a first gate insulating layer on the top surface; etching a portion of the first gate insulating layer to expose a first portion of the top surface; forming a second gate insulating over the first portion of the top surface, wherein the second gate insulating layer is thinner than the first gate insulating layer; forming a gate conductor over the first gate insulating layer and over the second gate insulating layer; removing first, second, and third portions of the gate conductor, wherein the first portion of the gate conductor overlies the second gate insulating layer and a first region in the active area, the second portion of the gate conductor overlies the second gate insulating layer and a second region in the active area, and the third portion of the gate conductor overlies the first gate insulating layer and a third region in the active area; doping the third region to a higher concentration of the first conductivity type; doping the first region and the second regions to a second conductivity type; and forming contacts to the first, second, and third regions.