Patent ID: 8546886

Claim:
An integrated circuit structure comprising: a semiconductor substrate; a p-type metal-oxide-semiconductor (PMOS) device and an n-type metal-oxide-semiconductor (NMOS) device at a front surface of the semiconductor substrate; a first dielectric layer on a backside of the semiconductor substrate, wherein the first dielectric layer applies a first stress of a first stress type to the semiconductor substrate, wherein the first dielectric layer is overlying the semiconductor substrate and overlapping a first one of the PMOS device and the NMOS device, and is not overlapping a second one of the PMOS device and the NMOS device; and a second dielectric layer on the backside of the semiconductor substrate, wherein the second dielectric layer applies a second stress to the semiconductor substrate, wherein the second stress is of a second stress type opposite to the first stress type, and wherein the second dielectric layer overlaps a second one of the PMOS device and the NMOS device.