薄硅层阶梯埋氧PSOI高压器件新结构

基于介质电场增强ENDIF理论,提出了一种薄硅层阶梯埋氧型部分SOI(SBPSOI)高压器件结构。埋氧层阶梯处所引入的电荷不仅增强了埋层介质电场,而且对有源层中的电场进行调制,使电场优化分布,两者均提高器件的击穿电压。详细分析器件耐压与相关结构参数的关系,在埋氧层为2μm,耐压层为0.5μm时,其埋氧层电场提高到常规结构的1.5倍,击穿电压提高53.5%。同时,由于源极下硅窗口缓解SOI器件自热效应,使得在栅电压15V,漏电压30V时器件表面最高温度较常规SOI降低了34.76K。

A Novel Thin Silicon Layer PSOI High Voltage Device Structure with Step Buried Oxide

Based on ENDIF (ENhanced DIelectric layer Field),a novel PSOI (partial silicon-on-insulator) high voltage device with Step Buried oxide SBPSOI is proposed. The charges of step buried oxide not only enhance the electric field of dielectric buried layer but also modulate the active region to optimize the electric field distribution,and so increase the breakdown voltage (VB,V). The relationship of structure parameters with breakdown voltage was analyzed for the proposed device,dielectric buried layer electric field is as high as thrice of the conventional SOI device,the breakdown voltage increases by 53.5% in a 2 μm-thick dielectric buried layer and 0.5 μm-thick top silicon layer. The silicon window underneath a source alleviates SHE (Self-Heating Effect),to reduce the surface maximal temperatures by 34.76 K in comparison with the conventional SOI at 15 V gate-source voltage and 30 V drain-source voltage.