Multi-height multi-composition semiconductor fins

摘要

A dielectric material layer is formed on a semiconductor-on-insulator (SOI) substrate including a top semiconductor layer containing a first semiconductor material. An opening is formed within the dielectric material layer, and a trench is formed in the top semiconductor layer within the area of the opening by an etch. A second semiconductor material is deposited to a height above the top surface of the top semiconductor layer employing a selective epitaxy process. Another dielectric material layer can be deposited, and another trench can be formed in the top semiconductor layer. Another semiconductor material can be deposited to a different height employing another selective epitaxy process. The various semiconductor material portions can be patterned to form semiconductor fins having different heights and/or different compositions.

主权项

1. A method of forming a semiconductor structure comprising:
forming a first dielectric material layer on a top surface of a semiconductor layer of a semiconductor-on-insulator (SOI) substrate, said semiconductor layer being a first single crystalline semiconductor material portion comprising a first single crystalline semiconductor material; forming a first trench through said first dielectric material layer and an upper region of said semiconductor layer; growing a second single crystalline semiconductor material portion from surfaces of said semiconductor layer within said first trench in a first selective epitaxy process, wherein said second single crystalline semiconductor material portion comprises a second single crystalline semiconductor material and fills said first trench; forming a second dielectric material layer on said top surface of said first dielectric material layer and a top surface of said second single crystalline semiconductor material portion; forming a second trench through said second dielectric material layer, said first dielectric material layer, and another upper region of said semiconductor layer; and growing a third single crystalline semiconductor material portion from surfaces of said semiconductor layer within said second trench by a second selective epitaxy process, wherein said third single crystalline semiconductor material portion comprises a third single crystalline semiconductor material and fills said second trench.