Methods of forming replacement gate structures using a gate height register process to improve gate height uniformity and the resulting integrated circuit products

Abstract

One method disclosed includes, among other things, forming a gate registration structure above an isolation region, wherein the gate registration structure comprises a plurality of layers of material, the uppermost layer of which is a polish-stop layer, forming first and second sacrificial gate structures above first and second active regions, respectively, wherein the first and second sacrificial gate structures abut and engage opposite sides of the gate registration structure, and performing at least one first chemical mechanical polishing (CMP) process to remove the gate cap layer so as to thereby expose a sacrificial gate electrode in each of the first and second sacrificial gate structures, wherein the uppermost layer of the gate registration structure serves as a polish-stop layer during the at least one first CMP process.