基于求解二维Po isson方程,分析了具有埋氧层界面电荷的SO I结构纵向击穿特性,提出了界面电荷耐压模型。该模型通过埋氧层界面电荷来调制硅层和埋氧层电场,获得极高击穿电压。进一步提出临界界面电荷面密度概念,给出其工程化应用的近似公式。并对文献中的不同结构SO I器件的纵向耐压进行计算。解析结果和试验结果或M ED IC I仿真结果吻合良好。
A new 2D analytical model for the surface electrical field distribution and optimization of bulk-silicon double RESURF devices is presented. Based on the solution to the 2D Poisson＇s equation, the model gives the influence on the surface electrical field of the drain bias and structure parameters such as the doping concentration,the depth and the position of the p-top region, the thickness and the doping concentration of the drift region, and the substrate doping concentration. The dependence of breakdown voltage on the length and doping concentration of the drift region is also calculated. Further more,an effective way to gain the optimum high-voltage is also proposed. All analytical results are verified by simulation results obtained by MEDICI and previous experimental data,showing the validity of the model presented here.
