针对功率集成电路中的高压器件应用,提出一种局部电荷补偿超结横向双扩散金属氧化物半导体(LDMOS)器件结构。利用常规LDMOS工艺,通过调整n阱的版图尺寸,在漏区形成局部的电荷补偿,可以缓解横向超结器件中存在的衬底辅助耗尽效应,促进超结的电荷平衡。n型电荷补偿区与P型衬底在超结下方形成pn结,可以同时优化横向和纵向电场分布,提高超结器件的耐压。此器件结构可以通过BCD工艺实现,适用于功率集成电路。三维器件仿真结果表明,新结构的器件耐压达到490V,较常规的电荷补偿超结器件提高了53%。
A super junction lateral double-diffusion MOSFET (LDMOS) with partial charge com- pensation was proposed for applications of high voltage devices in power integration circuits (PIC). Par- tial charge compensation was achieved at drain by modulating the layout size of n-well region in conven- tional LDMOS process, which relieved the substrate-assisted depletion effect existing in lateral super junction device and promoted the charge balance. The pn junction was instituted by n-type charge com- pensation region and p-type substrate and optimized synchronously the lateral and vertical electric field distribution, which improved the breakdown voltage of the super junction device. The proposed structure can be implemented by BED (bipolar, CMOS, DMOS) process for PIC. Three dimensional device sim- ulation results indicate that the breakdown voltage of the proposed structure achieves 490 V, which in- creases 53% compared with that of the conventional charge compensation super junction device.