非平衡超结器件的电荷补偿能力在薄层SOI器件中受到限制,文中提出一种具有T型电荷补偿区的器件结构。通过漏端刻蚀的PSOI结构使硅衬底与埋氧层同时参与纵向耐压,可以提高非平衡超结n区的电荷补偿能力;在埋氧层刻蚀区增加垂直的n型补偿区,弥补埋氧层的缺失。由横向的非平衡超结n区和漏端垂直的n区共同构成T型补偿区,可以有效缓解薄层SOI超结器件中的衬底辅助耗尽效应,优化横向电场,提高器件的耐压。器件的制作可以通过改进传统的PSOI工艺实现,应用于SOI功率集成电路。三维器件仿真结果表明,新结构下的器件耐压达到290V,相对于常规的SOI超结器件和非平衡超结器件提高了267%和164%。
Because the charge compensation of unbalanced super junction(SJ) device is restricted in thin SOI devices,a device structure with T-type charge compensation region is proposed in this paper.The partial SOI structure formed by drain region etching makes the silicon substrate and buried oxide(BOX) together undertake voltage,which improves the charge compensation capability of unbalanced SJ n-pillars.A vertical n-type compensation region is implemented to make up a loss of the etched BOX.Lateral n-pillars and vertical n-type region together constitute the T-type charge compensation region which suppresses the substrate-assisted depletion effect.The lateral electric field is improved resulting in the increase of the breakdown voltage(BV).The fabrication process is implemented by mending the conventional partial SOI process for the application of SOI power integrated circuits(PICs).Simulation results indicate that the BV of proposed structure achieves 290 V,which increases by 267% and 164% compared with conventional one and the unbalanced SJ structure.