Semiconductor device having trench isolation structure and method of fabricating the same

Abstract

A semiconductor device having a trench isolation structure and a method of fabricating the same are provided. The device has a trench region and an isolation structure. The trench region is disposed to define an active region at a predetermined region of an SOI substrate formed by sequentially stacking a buried insulating layer and an upper silicon layer on a base substrate. The isolation structure fills an inside of the trench region. The trench region has a deep trench region where the upper silicon layer penetrates to the buried insulating layer and a shallow trench region existing at an outside of the deep trench region. The method of forming a trench region with deep and shallow trench regions includes patterning an upper silicon layer of an SOI substrate. A trench oxide layer and a trench liner are conformally formed on a sidewall and a bottom of the trench region. The trench liner on the bottom of the trench region, the trench oxide layer, and the upper silicon layer are successively patterned to form the deep trench region where the buried insulating layer is exposed. The trench region existing at an outside of the deep trench region corresponds to the shallow trench region.