Monolithic integration of a MOSFET with a MEMS device

Patent Number: 6,531,331
Issued: 3/11/2003
Official Filing: View the Complete Patent
Abstract: An integrated microelectromechanical system comprises at least one MOSFET interconnected to at least one MEMS device on a common substrate. A method for integrating the MOSFET with the MEMS device comprises fabricating the MOSFET and MEMS device monolithically on the common substrate. Conveniently, the gate insulator, gate electrode, and electrical contacts for the gate, source, and drain can be formed simultaneously with the MEMS device structure, thereby eliminating many process steps and materials. In particular, the gate electrode and electrical contacts of the MOSFET and the structural layers of the MEMS device can be doped polysilicon. Dopant diffusion from the electrical contacts is used to form the source and drain regions of the MOSFET. The thermal diffusion step for forming the source and drain of the MOSFET can comprise one or more of the thermal anneal steps to relieve stress in the structural layers of the MEMS device.
Filed: 7/16/2002
Application Number: 10/197,202
Government Interests: STATEMENT OF GOVERNMENT INTEREST This invention was made with Government support under Contract No. DE-NA0003525 awarded by the United States Department of Energy/National Nuclear Security Administration. The Government has certain rights in the invention.