Patent ID: 9520296
Filing Date: 2016-12-13
CPC Classification: H01L

Claim Text:
1. A method of forming vertical structures, comprising: providing a substrate; forming a first oxide layer over the substrate; forming a shallow trench isolation to divide the substrate into a first region and a second region; forming a first dummy layer over the first oxide layer and the shallow trench isolation; etching the first oxide layer and the first dummy layer to form a first recess in the first region and a second recess in the second region; forming a second dummy layer in the first recess and the second recess; removing the first dummy layer; removing the first oxide layer; etching a portion of the shallow trench isolation; and etching the substrate to make the substrate aligned with a top of the shallow trench isolation and to form a first vertical structure in the first region and a second vertical structure in the second region.