SEMICONDUCTOR FIN STRUCTURES AND METHODS FOR FORMING THE SAME

摘要

A method includes etching a semiconductor substrate to form a semiconductor strip and trenches on opposite sidewalls of the semiconductor strip. A spacer is formed on a sidewall of the semiconductor strip which is used as an etching mask to extend the trenches down into the semiconductor substrate. A dielectric material is filled into the trenches and then planarized to form insulation regions in the trenches. The insulation regions are recessed. After the recessing, top surfaces of the insulation regions are lower than a top surface of the semiconductor strip and a gate structure may be formed thereon.

主权项

1. A method, comprising:
etching a semiconductor substrate to form a semiconductor strip, wherein trenches are formed in the semiconductor substrate, and wherein the trenches are on opposite sidewalls of the semiconductor strip; forming a spacer on a sidewall of the semiconductor strip; using the spacer as an etching mask to extend the trenches down into the semiconductor substrate, wherein the semiconductor substrate is etched; filling a dielectric material into the trenches; planarizing the dielectric material to form insulation regions in the trenches; and recessing the insulation regions, wherein after the recessing, top surfaces of the insulation regions are lower than a top surface of the semiconductor strip.