Methods of manufacturing a semiconductor device including cmos transistor having different pmos and nmos gate electrode structures

Abstract

In a method of manufacturing a semiconductor device, a gate insulation layer is formed on a substrate including a first channel of a first conductive type and a second channel of a second conductive type different from the first conductive type. A first conductive layer including a first metal is formed on the gate insulation layer, and a second conductive layer including a second metal different from the first metal is formed on the first conductive layer formed over the second channel. The second conductive layer is partially removed by a wet etching process to form a second conductive layer pattern over the second channel.