Patent ID: 9741625
Date: 2017-08-22
CPC Classifications: H01L

Claim:
1. A method of forming a semiconductor device, the method comprising: providing an SOI substrate comprising a base substrate, a buried insulating material layer formed on said base substrate, and an active semiconductor layer formed on said buried insulating material layer; forming a germanium-comprising layer on an exposed surface of said active semiconductor layer; forming a passivation layer above said germanium-comprising layer; forming a trench isolation structure extending through said germanium-comprising layer and said active semiconductor layer, said trench isolation structure separating a first device region from a second device region; performing an annealing process after said trench isolation structure is formed and while said passivation layer covers said germanium-comprising material in said first device region, said annealing process converting said active semiconductor layer in said second device region to a germanium-comprising active layer which is formed on said buried insulating material layer and converting said germanium-comprising material in said second device region to an oxide layer which is formed on said germanium-comprising active layer; and removing said oxide layer to expose an upper surface of said germanium-comprising active layer.