Blanket EPI super steep retrograde well formation without Si recess

摘要

A method of forming SSRW FETs with controlled step height between a field oxide and epitaxially grown silicon and the resulting devices are provided. Embodiments include providing a SiN layer on a substrate, forming first, second, and third spaced STI regions of field oxide through the SiN layer and into the substrate, removing a top portion of the field oxide for each STI region by a controlled deglaze, removing the SiN layer, forming an n-type region in the substrate between the first and second STI regions and a p-type region in the substrate between the second and third STI regions, and epitaxially growing a Si based layer on the substrate over the n-type and p-type regions.

主权项

1. A method comprising:
providing a sacrificial oxide layer on a substrate; providing a silicon nitride (SiN) layer above the sacrificial oxide layer; forming first, second, and third spaced shallow trench isolation (STI) regions of field oxide through the SiN layer and into the substrate; removing a top portion of the field oxide for each STI region by a controlled deglaze; removing the SiN layer; forming an n-type region in the substrate between the first and second STI regions and a p-type region in the substrate between the second and third STI regions; removing the sacrificial oxide layer by precleaning; removing 4 nanometers (nm) of field oxide from each STI region during the precleaning; and epitaxially growing, after the precleaning, a silicon (Si) based layer on the substrate over the n-type and the p-type regions.