Separate layer formation in a semiconductor device

摘要

A semiconductor device is formed. A first gate dielectric layer is formed over the semiconductor layer. A first conductive layer is formed over the first gate dielectric. A first separation layer is formed over the first conductive layer. A trench is formed in the semiconductor layer to separate the first mesa and the second mesa. The trench is filled with an isolation material to a height above a top surface of the first conductive layer. The first conductive layer is removed from the second mesa. A second conductive layer is formed over the first separation layer of the first mesa and over the second mesa. A planarizing etch removes the second conductive layer from over the first mesa. A first transistor of a first type is formed in the first mesa, and a second transistor of a second type is formed in the second mesa.