Patent ID: 8895384
Filing Date: 2014-11-25
Classification: H01L

Abstract:
1. A method comprising: forming an insulator layer on a substrate and a sacrificial layer on the insulator layer; patterning the insulator layer and the sacrificial layer to form a plurality of dummy gate structures; forming sidewall structures on sidewalls of the dummy gate structures; removing the sacrificial layers from a first dummy gate structure and a second dummy gate structure to form a first trench and a second trench, respectively, defined by the sidewall structures; removing the insulator layer forming a bottom portion of the second trench while protecting the insulator layer in the first trench; forming a channel material on the substrate in the first trench while the insulator layer in the second trench acts as a mask in the second trench; removing the insulator layer in the second trench after the channel material is formed; and filling remaining portions of the first trench and the second trench with gate material to form a metal gate in each of the first trench and the second trench.