Title :
A first-order charge conserving MOS capacitance model
Author :
Sakallah, Karem A. ; Yen, Yao-Tsung ; Greenberg, Steve S.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA
fDate :
1/1/1990 12:00:00 AM
Abstract :
The Meyer capacitance model (see RCA Rev., vol.32, p.42-63, 1971) fails to obey the charge conservation law. It is shown that the charge nonconservation in the Meyer model is not due to any physical assumptions. Rather, it is caused by the mathematical error of characterizing a multidimensional function (the stored charge on the four terminals of a MOSFET) by an incomplete subset of its partial derivatives (the partial derivatives of the gate charge). This conclusion is supported by developing and implementing a correct mathematical characterization of the MOS charges based on the same physical assumptions used in the Meyer model. One important outcome of this exercise is that the nonreciprocal nature of MOS capacitive coupling is evident even in a first-order physical model of the device
Keywords :
capacitance; insulated gate field effect transistors; semiconductor device models; MOSFET; Meyer capacitance model; capacitive coupling; charge nonconservation; first-order charge conserving MOS capacitance model; first-order physical model; gate charge; mathematical error; multidimensional function; nonreciprocal nature; partial derivatives; Capacitance; Circuit simulation; Design automation; Differential equations; Lead; MOSFET circuits; Mathematical model; Multidimensional systems; Nonlinear equations; SPICE;
Journal_Title :
Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on
