The Influence of Impurity Scattering in Highly Doped SOI-MOSFETs

The relationship between the most commonly used empirical and physical mobility models is investigated. The parameters of the empirical model are given as a function of those of the physical model. Based on these relations, it will be shown that the three empirical mobility parameters ¿0, ¿1 and ¿2 are influenced by impurity scattering which increases with the doping concentration. This mechanism can be dominant in the linear mobility reduction factor ¿1 which may become negative. Experimental results of highly doped SOI-MOSFETs demonstrate that impurity scattering cannot be neglected any longer at ambient and higher temperatures.