US Patent 7411271 Complementary metal-oxide-semiconductor field effect transistor

A complementary metal-oxide-semiconductor field effect transistor (CMOSFET) is provided. The CMOSFET includes a substrate of a first conductivity type, a first epitaxial layer, a well, a second epitaxial layer of a second conductivity type, a first sinker, a second sinker, a first buried layer and a second buried layer. The first and the second epitaxial layer are sequentially disposed on the substrate. The first sinker and the first buried layer separate a first region from the second epitaxial layer. The second sinker and the second buried layer separate a second region from the second epitaxial layer. The well is disposed in the first region. A first transistor is disposed in the well. A second transistor is disposed in the second region. A deep trench isolation is disposed between the first and the second region and extends from the substrate to the upper surface of the second epitaxial layer.