Cmos transistor design for shared n+/p+ electrode with enhanced device performance

Abstract

An integrated circuit and a method of making a transistor thereof are provided. In one aspect, the method includes the steps of forming a gate dielectric layer on the substrate and forming a gate electrode on the gate dielectric layer with a lower surface, a midpoint, and a quantity of p-type impurity. A quantity of nitrogen is introduced into the gate electrode whereby the quantity nitrogen has a peak concentration proximate the lower surface. A quantity of germanium is introduced into the gate electrode and first and second source/drain regions are formed in the substrate. The method enables simultaneous formation of n-channel and p-channel gate electrodes with work functions tailored for both types of devices.