A physical model for the gate current injection in p-channel MOSFET´s

A quantitative physical model for calculating the hot-electron injection probability, I/sub G//I/sub SUB/, for both buried and surface p-channel MOSFETs is presented. The model utilizes the two-dimensional potential contours generated by PISCES, and integrates the probability of substrate hot-electron injection across the high-field region near the drain. The known phenomenon that buried-channel (BC) PMOS has higher hot-electron injection probability but lower channel field (I/sub SUB//I/sub D/) than a similar surface-channel (SC) device is successfully modeled. This phenomenon can be attributed to the larger energy band hump-up near the drain and the larger oxide field (and thus greater barrier lowering) at a given bias condition for the buried-channel device. The I/sub G/ characteristics can be obtained from the calculated I/sub G//I/sub SUB/ ratio, using readily available I/sub SUB/ values.<>