Method of Forming Trench in Semiconductor Substrate

摘要

The present invention provides a method of forming a trench in a semiconductor substrate. First, a first patterned mask layer is formed on a semiconductor substrate. The first patterned mask layer has a first trench. Then, a material layer is formed along the first trench. Then, a second patterned mask layer is formed on the material layer to completely fill the first trench. A part of the material layer is removed when the portion of the material layer between the second patterned mask layer and the semiconductor substrate is maintained so as to form a second trench. Lastly, an etching process is performed by using the first patterned mask layer and the second patterned mask layer as a mask.

主权项

1. A method of forming a trench in the substrate, comprising:
providing a substrate; forming a first patterned mask layer on the substrate, wherein the first patterned mask layer has a first trench with a bottom surface and at least a sidewall; forming a material layer on the sidewall of the first trench; forming a second patterned mask layer to completely fill the first trench; completely removing the material layer from the substrate to form a second trench between the first patterned mask layer and the second patterned mask layer; and after forming the second trench, performing an etching process by using the first patterned mask layer and the second patterned mask layer as a mask.