MEMS --CMOS A METHOD FOR INTEGRATING COMPLEMENTARY METAL-OXIDE-SEMICONDUCTOR CMOS DEVICES WITH MICROELECTROMECHANICAL SYSTEMS MEMS DEVICES USING A FLAT SURFACE ABOVE A SACRIFICIAL LAYER

摘要

A method of integrating a complementary metal-oxide-semiconductor (CMOS) device with a microelectromechanical system (MEMS) device using a flat surface over a sacrificial layer is provided. In some embodiments, a back-end-of-line (BEOL) interconnect structure covering a semiconductor substrate is formed, where the BEOL interconnect structure includes a first dielectric region. A sacrificial layer is formed on the first dielectric region, and a second dielectric region covering the sacrificial layer and the first dielectric region is formed. Planarization is performed on the upper surface of the second dielectric region to planarize the upper surface of the second dielectric region. A MEMS structure is formed on the flat top surface of the second dielectric region. Cavity etching is performed on the sacrificial layer through the MEMS structure to remove the sacrificial layer and form a cavity in place of the sacrificial layer. An integrated circuit (IC) resulting from the method is also provided.