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Title: Monolithic integration of a MOSFET with a MEMS device

Patent ·
OSTI ID:875099

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.

Research Organization:
Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
DOE Contract Number:
AC04-94AL85000
Assignee:
Sandia Corporation (Albuquerque, NM)
Patent Number(s):
US 6531331
OSTI ID:
875099
Country of Publication:
United States
Language:
English

References (8)

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