The method of forming a metal gate

Method of forming a metal gate electrode, comprising: providing a semiconductor substrate, is formed on the semiconductor substrate having a first and a second dummy gate dummy gate; removing the second dummy gate, forming a second trench in the a second trench sidewall, a bottom surface forming a second functional layer and a second sacrificial layer; removing the second sacrificial layer and the second functional layer, exposing the first gate of the first dummy region; removing the first dummy gate, forming a first trench in the first trench side wall, a bottom surface forming a first functional layer and the first sacrificial layer; removing the first sacrificial layer and the second sacrificial layer, the first function layer and the second surface of the functional layer to form a metal electrode layer, the metal electrode layer, a first functional layer and the second functional layer chemical mechanical polishing process to form a first gate metal and a second metal gate. Since only a polishing process is chemical-mechanical polishing a metal layer forming a metal gate electrode, can effectively control the height of the metal gate.