Patent ID: 6670248
Filing Date: 2003-12-30
Classification: H01L

Abstract:
A method for forming, on a semiconductor substrate, a dielectric layer having varying thickness and composition comprising:providing a semiconductor substrate; forming over said substrate a first dielectric layer having a first thickness; forming over said first dielectric layer a first layer of etch resistant material; removing a portion of said first layer of etch resistant material to expose a first region of the first dielectric layer; removing, by an etching process, the first region of the first dielectric layer and exposing, thereby, a first substrate surface region thereunder; removing the remaining first layer of etch resistant material; forming a second dielectric layer having a second thickness on said first substrate surface region; forming a blanket second layer of etch resistant material over the second dielectric layer and the first dielectric layer; removing a portion of said second layer of etch resistant material to expose a second region of the first dielectric layer; removing, by an etching process, the second region of the first dielectric layer and exposing, thereby, a second substrate surface region thereunder; removing the remaining portion of the second layer of etch resistant material; forming, by atomic layer chemical vapor deposition (ALCVD), a blanket third layer of high-k dielectric material having a third thickness over the second dielectric layer, the remaining portion of the first dielectric layer and the second substrate surface region.