Shallow trench isolation method for shielding trapped charge in a semiconductor device

摘要

A semiconductor structure and associated method for forming the semiconductor structure. The semiconductor structure comprises a first field effect transistor (FET), a second FET, and a shallow trench isolation (STI) structure. The first FET comprises a channel region formed from a portion of a silicon substrate, a gate dielectric formed over the channel region, and a gate electrode comprising a bottom surface in direct physical contact with the gate dielectric. A top surface of the channel region is located within a first plane and the bottom surface of the gate electrode is located within a second plane. The STI structure comprises a conductive STI fill structure. A top surface of the conductive STI fill structure is above the first plane by a first distance D₁ and is above the second plane by a second distance D₂ that is less than D₁.