具有高斯型的倾斜表面漂移区的LDMOS的器件特性研究  

Device Characteristics of LDMOS with the Gauss-Shape Surface in the Drift Region

作　　者：罗向东[1] 翟宪振[1] 戴珊珊[1] 余晨辉[1] 刘培生[1] 

机构地区：[1]南通大学江苏省专用集成电路设计重点实验室,江苏南通226019

出　　处：《计算机工程与科学》2012年第4期23-27,共5页Computer Engineering & Science

基　　金：国家自然科学基金资助项目(A040205);江苏省高校重大基础研究基金资助项目(08KJA510002);江苏省企业博士集聚计划;中国博士后基金资助项目(20110490075);南通市应用科技计划资助项目(K2008024)

摘　　要：本文提出一种具有高斯型的倾斜表面漂移区的LDMOS结构。P阱、沟道、源区、栅极等位于高斯中心的一侧,而漏端位于高斯中心的另一侧并靠近高斯中心,器件既具有倾斜表面漂移区的高耐压性,又具有VDMOS结构的高开态击穿特性和良好的安全工作区域。我们研究了高斯表面的弯曲程度对高斯型倾斜表面漂移区的影响。结果表明,P阱的长时间退火对具有高斯表面的漂移区的掺杂浓度分布有一定影响。具有高斯表面的倾斜漂移区的LDMOS结构在不同弯曲程度下器件耐压性和表面电场分布均匀性不同。高斯弯曲参数P在0.5左右时开态耐压性能最优,并且表面电场分布相对均匀;当弯曲参数P增大时,击穿特性基本饱和或略有下降。A LDMOS structure with the Gauss-shape surface in the drift region is proposed here.P-well,channel,source region,poly-silicon gate are set on one side of the Gauss center,and the drain region is put on the other side of the Gauss center.This LDMOS structure has high breakdown voltage of the LDMOS with a gradient surface in the drift region,but also has high on-state breakdown voltage and safe operating area.By changing the height factor of the Gauss shape of the drift region,the drift region with the Gauss-shape surface is studied.The results indicate that high temperature drive-in of p-well changes the net doping of the drift region with different Gauss-shape surfaces.The device breakdown voltage and the surface electric field profile of the LDMOS structures with different Gauss-shape surfaces are investigated by changing the height factor of the Gauss shape.There has an optimized on-state breakdown voltage and a smooth surface electric profile when the height factor is around 0.5.Meanwhile,when the height factor increases from 0.5 to 1.0,the on-state breakdown voltage is saturated.

关 键 词：LDMOS 高斯表面 漂移区 开态击穿电压 表面电场 

分 类 号：TP305[自动化与计算机技术—计算机系统结构]