On Basic Parameters and Radiation Theory of Non-Uniform Channel DMOS

摘要

Researching the non-uniform channel DMOS is the basic knowledge of the new generation high voltage power MOS devices and the important domain of the IC, smart power ICs. This dissertation investigates the basic parameters and the radiation theory of non-uniform channel DMOS. The threshold voltage model of micron and deep sub-micron non-uniform channel DMOS, the radiation threshold voltage model, the radiation mobility model and the transient response model of single ion radiation are internationally proposed for the first time. Theory study and model constitution would establish foundation of the next generation power devices and power circuits. The author's main contributions are outlined as following: The 2-D threshold voltage models of non-uniform channel DMOS is proposed. The model includes the micron and deep sub-micron non-uniform channel DMOS. Based on the 2-D distribution of channel impurity, Resolved the Poisson equation, the channel depletion width is obtained. So the channel depletion charge is calculated and the mathematics expression of the micron level threshold voltage model is obtained. The non-uniform channel impurity, the non-equal surface potential for the changing of balance energy band and the gate capacitor by the edge effect is thought about; the mathematics expression of the deep sub-micron non-uniform channel DMOS threshold voltage model is obtained. The results of the threshold voltage model agree well with those of the experiment, and those of the 2-D simulator MEDICI. The simplified expression of DMOS threshold voltage is given with the channel surface diffusion concentration changing from 2.0 x 10~(16) cm~(-3) to 10.0 x 10~(16) cm~(-3).