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 (/spl mu//sub acc/), measured for a wide range of doping concentrations (1/spl times/10/sup 16/ cm/sup -3/-4/spl times/10/sup 17/ cm/sup -3/) and at temperatures ranging from 25/spl deg/C to 150/spl deg/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, /spl mu//sub 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, /spl mu//sub acc/ is found to be lower than the bulk mobility values at all temperatures and effective fields.