METHOD OF FORMING FINFET HAVING FINS OF DIFFERENT HEIGHT

摘要

A device is fabricated on a silicon-on-insulator (SOI) wafer formed of a substrate, a bottom oxide layer on the substrate and an active silicon layer on the bottom oxide layer, where the active silicon layer has a surface opposite the bottom oxide layer. A first mask is formed over the surface at a first portion of the wafer, leaving a second portion of the wafer unmasked. The wafer is etched at the unmasked second portion of the wafer to form a depression in the active silicon layer. A thermal oxide layer is formed to substantially fill the depression, the first mask is removed, and fins are formed at the first and second portions of the wafer.

主权项

1. A device comprising:
an SOI wafer having a silicon layer having a top surface, the SOI wafer having a first portion and a second portion, the second portion including an etched depression having an oxidized bottom; an oxide layer in the etched depression having an oxide layer top surface, the oxide layer top surface being substantially even with the silicon layer top surface; and a plurality of mask portions on the silicon layer top surface and on the oxide layer top surface for defining a first plurality of fins at the first SOI wafer portion and a second plurality of fins at the second SOI wafer portion.