RF MEMS-CMOS Device Integration: An Overview of the Potential for RF Researchers

Over the past decades, a great deal of progress has been made in the development of semiconductor manufacturing processes. This in turn has made possible the monolithic integration of microelectromechanical systems (MEMS) devices with driving, controlling, and signal processing CMOS electronics [1][4]. There have been several successful well known commercial examples of integrated MEMS-CMOS devices, including the Analog Devices ADXL accelerometers [5], the Texas Instruments digital micromirror device (DMD) [6], the STMicroelectronics accelerometers and gyroscopes [6], and SiTime vacuum-encapsulated resonators [7]. More recently, Cavendish Kinetic [8] and WiSpry [9] launched their RF MEMS switches fabricated through MEMS-CMOS integration. While several techniques for MEMS-CMOS integrations have been widely employed for sensor and accelerometer applications, most of the work reported in literatures on RF MEMS has focused on devices fabricated using conventional surface micromachining techniques. It is the objective of this article to provide RF researchers with an overview of the potential of integrating MEMS with CMOS for RF MEMS applications.