SHALLOW TRENCH ISOLATION STRUCTURES

摘要

Shallow trench isolation structures are provided for use with UTBB (ultra-thin body and buried oxide) semiconductor substrates, which prevent defect mechanisms from occurring, such as the formation of electrical shorts between exposed portions of silicon layers on the sidewalls of shallow trench of a UTBB substrate, in instances when trench fill material of the shallow trench is subsequently etched away and recessed below an upper surface of the UTBB substrate.

主权项

1. A semiconductor device, comprising:
a semiconductor substrate comprising a first silicon layer, a second silicon layer, and a buried oxide layer disposed between the first silicon layer and the second silicon layer; a high-k gate dielectric layer formed on the first silicon layer; a shallow trench isolation structure formed in the semiconductor substrate, the shallow trench isolation structure comprising:
a shallow trench formed through the first silicon layer, the buried oxide layer and partially through the second silicon layer;a first liner conformally lining the shallow trench; anda trench fill material disposed in the shallow trench,wherein the first liner is formed of a material having etch selectivity with regard to the trench fill material.