Patent ID: 9484255
Filing Date: 2016-11-01
CPC Classification: H01L

Claim Text:
1. A method of forming contacts to an electrical device comprising: providing a first via to a first semiconductor device comprising at least one of a silicon and germanium containing source and drain region and providing a second via to a second semiconductor device comprising at least one of a silicon containing source and drain region; forming a material stack in the first and second via, the first material stack comprising a titanium layer and an aluminum layer; converting the aluminum layer of the first material stack within the second via to aluminum oxide; removing the aluminum oxide with an etch that is selective to the titanium layer; converting the titanium layer present in the second via to titanium oxide with an oxidation anneal, wherein during said oxidation anneal the aluminum layer in the first via alloys with the titanium layer and silicon from the silicon and germanium containing source and drain region; depositing a metal layer in the second via; and depositing a metal fill in one at least one of the first and second via.