Modeling and Analysis of MOS Capacitor Controlled by Independent Double Gates

P.K. Thakur, S. Mahapatra
Indian Institute of Science Bangalore, IN

Keywords: compact modeling, MOS capacitors, doubel gate MOSFETs, varactors

Summary:

This paper, for the first time, explores the charcatersictics of MOS capacitor controlled by independent double gates by numerical simulation and analytical modeling for its possible use in RF circuit design as a varactor. By numerical simulation it is shown how the quasi-static and non-quasi-static characteristics of the first gate capacitance could be tuned by the second gate biases. Effect of body doping and energy quantization are also discussed in this regard. A semi-empirical quasi-static model is also developed by using the existing incomplete Poisson solution of independent double gate transistors. Proposed model, which is valid from accumulation to inversion, is shown to have excellent agreement with numerical simulation for practical bias conditions.