Patent ID: 9299787
Filing Date: 2016-03-29
CPC Classification: H01L

Claim Text:
1. A method comprising: forming first fins on sidewalls of mandrels using epitaxial growth, the mandrels are on a buried insulator layer, the buried insulator layer is on a base substrate, the first fins have a first pitch between adjacent first fins, the first fins include a material of the IV semiconductor group, the first fins are grown in a pFET region and an nFET region; removing the mandrels; forming a conformal spacer layer directly on the first fins, the conformal spacer layer is in the nFET region and the pFET region; damaging a portion of the conformal spacer layer on a top surface and a first side surface of the first fins in the nFET region, a portion of the conformal spacer layer remains undamaged on a protected side of the first fins in the nFET region, the protected side of the first fins in the nFET region include surfaces opposite the first side surface, a mask protects the conformal spacer layer in the pFET region from damage; removing the damaged portion of the conformal spacer layer from the top surface and the first side surface of the first fins in the nFET region exposing a portion of the first fins in the nFET region; forming second fins on the exposed portion of the first fins using epitaxial growth, a bottom surface of the second fins is coplanar with a bottom surface of the first fins, the second fins have a second pitch between adjacent second fins, the second pitch is equal to the first pitch, the second fins include a material of the III-V semiconductor group, the second fins are grown in the nFET region; etching a top surface of the second fins to the top surface of the first fins, wherein the top surface of the second fins is coplanar with the top surface of the first fins; and removing the first fins from the nFET region.