Temperature dependence characterization of effective electron and hole mobilities in the accumulation layers of N- and P-type MOSFET's

Experimental results for the MOS electron and hole accumulation layer mobilities (mu(acc)), measured for a wide range of doping concentrations (1 x 10(16) cm(-3)-4 x 10(17) cm(-3)) and at temperatures ranging from 25 degrees C to 150 degrees C, indicate a "universal behavior" at high effective fields and over the temperature range of the measurement, similar to that of MOS inversion carriers. At low to moderate transverse fields, mu(acc) is found to be greater than the bulk mobility at lower temperatures, and gradually decreases toward the bulk mobility values with the increasing lattice temperature. However, for lower doping levels, mu(acc) is found to be lower than the bulk mobility values at all temperatures and effective fields.