Hybrid source and drain contact formation using metal liner and metal insulator semiconductor contacts

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 first metal layer and a second metal layer;
• converting the second metal layer of the first material stack within the second via to a second metal oxide;
• removing the second metal oxide with an etch that is selective to the first metal layer;
• converting the first metal layer present in the second via to first metal oxide with an oxidation anneal, wherein during said oxidation anneal the second metal layer in the first via alloys with the first metal layer and silicon from the silicon and germanium containing source and drain region to provide a binary metal semiconductor alloy;
• depositing a cap metal layer in the second via;
• and
• depositing a metal fill in one at least one of the first and second via.