Modeling of Vibrating-Body Field-Effect Transistors Based on the Electromechanical Interactions Between the Gate and the Channel

• Published in: IEEE transactions on electron devices Vol. 59; no. 8; pp. 2235 - 2242
• Main Authors: Ueki, Shinji, Nishimori, Yuki, Imamoto, Hiroshi, Kubota, Tomohiro, Kakushima, Kuniyuki, Ikehara, Tsuyoshi, Sugiyama, Masakazu, Samukawa, Seiji, Hashiguchi, Gen
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-08-2012; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Computer science; control theory; systems; Control theory. Systems; Electronics; Equations; Equivalent circuits; Exact sciences and technology; Logic gates; Mathematical model; metal-oxide-silicon field-effect transistors (MOSFETs); Micro- and nanoelectromechanical devices (mems/nems); microelectromechanical systems; MOSFETs; parallel-plate actuators; Robotics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Springs; Surface treatment; Transistors; MOSFET; Resistive circuit; Modeling; Cut off frequency; Silicon; Microelectromechanical device; Electromechanical system; Transconductance; Actuator; Electrical characteristic; Parallel plate; Equivalent circuits; MOS technology; Equation of motion; Coupled method; microelectromechanical systems; parallel-plate actuators; Antiresonance; Ladder circuit; Field effect transistor; Equivalent circuit; Mechanical system; metal-oxide-silicon field-effect transistors (MOSFETs); Capacitance; Vibrator; Current gain; Energy transfer
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2012.2199758

A coupled analysis method for the mechanical and electrical systems of vibrating-body field-effect transistors (VB-FETs) is described. To accommodate energy transfer between the gate and the FET channel, we represent the FET with a resistance-capacitance ladder circuit and use the Lagrange function to derive motion equations. By solving the equations, we derive the typical electrical characteristics of VB-FETs, namely, the transconductance and the current gain. The results show that the current gain is obtained even above the cutoff frequency of the FET at the antiresonance frequency of the mechanical vibrator. These characteristics strongly depend on the device dimensions and operating conditions. This means that a coupled analysis is helpful for determining an appropriate design of VB-FETs.