SiC MOS结构空间电荷区杂质离化的研究

Study of impurity ionization in SiC MOS structures

在研究SiCMOS表面空间电荷区杂质不完全离化的过程中引入了Frenkel Pool效应 ,并建立了在电场作用下SiC杂质离化的新模型 .基于对一维Poisson方程的求解 ,分析了场致离化对SiCMOS结构特性的影响 ,结果表明 ,电场的作用会提高SiC中杂质离化浓度 ,使析冻效应减弱 。

Frenkel-Pool effect has been taken into account in studying incomplete ionization of impurity in the SiC MOS devices, and a new model of impurity ionization in SiC is developed. The influence of field-aided-ionization on SiC MOS structure is investigated based on the one-dimensional numerical solving of Poisson's equation. The results show that Frenkel-Pool effect can enhance the impurity ionization by lowering the effective barrier height, and induce a voltage shift in the SiC MOS C-V characteristics. The classical impurity freeze-out effect seems weakened in SiC MOS space-charge-region. The model is more applicable for studying SiC devices.