High-K dielectric structure for deep trench isolation

摘要

A method of deep trench isolation which includes: forming a semiconductor on insulator (SOI) substrate comprising a bulk semiconductor substrate, a buried insulator layer and a semiconductor layer on the buried insulator layer (SOI layer), one portion of the SOI substrate having a dynamic random access memory buried in the bulk semiconductor substrate (eDRAM) and a deep trench fin contacting the eDRAM and a second portion of the SOI substrate having an SOI fin in contact with the buried insulator layer; conformally depositing sequential layers of oxide, high-k dielectric material and sacrificial oxide on the deep trench fin and the SOI fin; stripping the sacrificial oxide over the SOI fin to expose the high-k dielectric material over the SOI fin; stripping the exposed high-k dielectric material over the SOI fin to expose the oxide layer over the SOI fin.

主权项

1. A method of deep trench isolation comprising:
forming a semiconductor on insulator (SOI) substrate comprising a bulk semiconductor substrate, a buried insulator layer and a semiconductor layer on the buried insulator layer (SOI layer), one portion of the SOI substrate having a dynamic random access memory buried in the bulk semiconductor substrate (eDRAM) and a deep trench fin contacting the eDRAM and a second portion of the SOI substrate having an SOI fin in contact with the buried insulator layer; conformally depositing a layer of oxide on the deep trench fin and the SOI fin; conformally depositing a layer of high-k dielectric material on the oxide; conformally depositing a sacrificial oxide on the high-k dielectric material; stripping the sacrificial oxide over the SOI fin to expose the high-k dielectric material over the SOI fin while avoiding stripping the sacrificial oxide over the deep trench fin contacting the eDRAM; and stripping the exposed high-k dielectric material over the SOI fin to expose the oxide layer over the SOI fin.