Review: Semiconductor Piezoresistance for Microsystems

• Published in: Proceedings of the IEEE 2009-03, Vol.97 (3), p.513-552
• Main Authors: Barlian, A. Alvin, Park, Woo-Tae, Mallon, Joseph R., Rastegar, Ali J., Pruitt, Beth L.
• Format: Article
• Language: English
• Subjects: Acoustic wave devices, piezoelectric and piezoresistive devices; Applied sciences; Design engineering; Devices; Electronics; Exact sciences and technology; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Materials selection; MEMS; Micro- and nanoelectromechanical devices (mems/nems); Microelectromechanical systems; Microelectronic fabrication (materials and surfaces technology); microfabrication; Micromachining; Micromechanical devices; microsensors; Physics; Piezoresistance; Piezoresistive devices; piezoresistor; Piezoresistors; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Semiconductors; Sensor systems; Sensors; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Silicon devices
• ISSN: 0018-9219; 1558-2256
• DOI: 10.1109/JPROC.2009.2013612

Piezoresistive sensors are among the earliest micromachined silicon devices. The need for smaller, less expensive, higher performance sensors helped drive early micromachining technology, a precursor to microsystems or microelectromechanical systems (MEMS). The effect of stress on doped silicon and germanium has been known since the work of Smith at Bell Laboratories in 1954. Since then, researchers have extensively reported on microscale, piezoresistive strain gauges, pressure sensors, accelerometers, and cantilever force/displacement sensors, including many commercially successful devices. In this paper, we review the history of piezoresistance, its physics and related fabrication techniques. We also discuss electrical noise in piezoresistors, device examples and design considerations, and alternative materials. This paper provides a comprehensive overview of integrated piezoresistor technology with an introduction to the physics of piezoresistivity, process and material selection and design guidance useful to researchers and device engineers.