Patent ID: 7202140

Claim:
A method for forming a semiconductor structure having devices formed on both sides; comprising the steps of: a) providing a first substrate and a second substrate; said first substrate is comprised of Ge; said second substrate is comprised of silicon; b) forming a first dielectric layer over said first substrate; c) forming a first insulating layer over said second substrate; d) bonding said first dielectric layer and said first insulating layer to form a first structure; said first structure comprised of the first substrate, an insulation layer and the second substrate; the bonded first dielectric layer and the first insulating layer form the insulation layer; e) removing a portion of the first substrate to reduce the thickness of the first substrate; f) forming via plugs through the first substrate and the insulation layer and at least partially through said second substrate; g) forming first active devices on the surface of said first substrate; h) forming a first capping layer over the first active devices and the first substrate; i) removing a portion of the second substrate to reduce the thickness of the second substrate to expose said via plugs; and j) forming second active devices on the second substrate.