Non-planar transistor and method of forming the same

摘要

A non-planar transistor is provided. It includes a substrate, a fin structure, a gate structure, a spacer structure and a source/drain region. The fin structure is disposed on the substrate, the gate structure is disposed on the fin structure. The spacer structure is disposed on a sidewall of the gate structure. The spacer structure includes a first spacer with a first height and a second spacer with a second height, wherein the first spacer is disposed between the second spacer, and the first height is different from the second height. The source/drain region is disposed in a semiconductor layer at two sides of the spacer structure. The present invention further provides a method of forming the same.

主权项

1. A method of forming a non-planar transistor, comprising:
forming a fin structure on a substrate; forming a gate structure on the fin structure; forming a spacer structure on a sidewall of the gate structure, wherein the spacer structure comprises a first spacer and a second spacer, the first spacer is disposed between the gate structure and the second spacer, and a height of the first spacer is different from a height of the second spacer; and forming a source/drain region in the fin structure at one side of the spacer structure, wherein the step of forming the fin structure comprises:
providing at least an active region and an isolation region encompassing the active region;performing an isotropical etching process to form a first trench in the isolation region;performing an anisotropical etching process to enlarge a bottom surface of the first trench to form a second trench; andperforming an isotropical etching process to deepen a bottom surface of the second trench to form a third trench, making the substrate in the active region become the fin structure.