一种改善VDMOSFET高频性能新结构的分析与研究

Analysis of a Novel Power VDMOSFET Structure with Reducing Gate Charge

栅电荷是低压功率MOSFETs开关性能的一项很重要的参数。器件优值(Ron*Qg)是常用来量化开关性能的指标。文中对传统结构和新结构的栅电荷特性进行了二维数值模拟,并推导出可用于计算栅电荷的解析模型。仿真结果表明新结构相对于常规结构,栅电荷降低42.93%,器件优值降低37.05%。最后对新结构进行了参数优化。

For the switching performance of low-voltage （LV） power MOSFETs, the gate charge （Qg） is an important parameter. The so-called figure-of-merit （FOM）, which is defined as the product of the on-resistance （Ron） and Qg is commonly used for quantifying the switching performance, analyzed the switching behavior in power MOSFETs by using 2 dimension simulations, focusing on the gate charge. An analytical model for calculating the Qg, which takes into account the geometry dependence was devived. The simulation results of new structure show that the Qg is reduced 42.93% and the figure-of-merit is reduced to 37. 05%. the new structure is optimized for the best characteristics.