抄録
A parameter extraction circuit for MOSFET operating in weak inversion region is proposed. The extracted device parameter related with body effect for MOSFET is a coefficient of gate voltage degradation in a device model function deriving from the diffusion current of pn junction. With the parameter extraction circuit, the effect of gate voltage potential in MOS diode part can be controlled to be equal to that of reverse biased pn junction. So the degradation related with body effect can be compensated in spite of the different voltage between a source terminal and a bulk terminal. The proposed parameter extraction circuit can be applicated to two MOSFETs voltage subtractor and voltage follower operating under low power supply in order to compensate the body effect for MOSFETs. The characteristics of the extraction circuit fabricated with a standard 0.18μ m n-well CMOS technology are measured to investigate the basic principle. The thermal chracteristics are also measured. Measured characteristics of the proposed circuit fit to the theoretical chracteristics exactly.