具有多段分裂栅的屏蔽栅沟槽型MOSFET特性研究  

Study on characteristics of shielded gate trench MOSFET with multi-segment split gate

作　　者：李嘉楠 冯全源[1] 陈晓培[1] LI Jianan;FENG Quanyuan;CHEN Xiaopei(Institute of Microelectronics,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]西南交通大学微电子研究所,四川成都611756

出　　处：《电子元件与材料》2023年第11期1324-1328,共5页Electronic Components And Materials

基　　金：国家自然科学基金(62090012);四川省重点研发项目(2023YFG0004)。

摘　　要：为了能够有效调制屏蔽栅沟槽型(Shielded Gate Trench,SGT)MOSFET器件阻断状态下的电场分布,改善器件的电荷耦合效应,从而提高器件击穿电压(BV)和特征导通电阻(Ron,sp)之间的折衷关系,研究提出了一种具有多段分裂栅的SGT MOSFET结构。该结构是将传统的SGT MOSFET沟槽中的屏蔽栅分裂成三部分,最上层的屏蔽栅接源极,中间和最下层的屏蔽栅为浮空,分别命名为UFG和LFG。新结构器件在阻断状态下可以在n型漂移区引入两个额外的电场峰值,使得电场分布更加均匀。Sentaurus TCAD软件仿真结果显示,在元胞参数相同的条件下,相较传统SGT MOSFET,具有双段浮空栅(DSFSGT)MOSFET的BV和优值(Figure of Merit,FOM)分别提高了37.7%和66.7%,BV达到了173.6 V,FOM达到了177.3 V2/(mΩ·mm^(2));相较单段浮空栅(SFSGT)MOSFET,BV和优值分别提高了10.7%和19.8%。Here a shielded gate trench(SGT)MOSFET structure was proposed with multi-segment split gate to effectively modulate the electric field distribution in the blocking state,to improve the charge coupling effect,and to better compromise the relationship between the breakdown voltage(BV)and the characteristic on-resistance(Ron,sp)of the device.The traditional SGT MOSFET has three parts.The upper shield gate is connected to electrode,and the middle and lower shield gates are floating,which are named UFG and LFG respectively.The new structure introduces two additional electric field peaks in n-type drift region in the blocking state to achieve more uniform electric field distribution.Simulation results from Sentaurus TCAD software show that under the same cell parameters the BV and figure of merit(FOM)of MOSFET with dual-segment floating gate(DSFSGT)are increased by 37.7%and 66.7%from traditional SGT MOSFET,respectively.The BV and FOM can reach up to 173.6 V and 177.3 V2/(mΩ·mm^(2)),respectively.Compared with single-segment floating gate(SFSGT)MOSFET,the BV and FOM are improved by 10.7%and 19.8%respectively.

关 键 词：分裂栅 电场分布 MOSFET SGT 击穿电压 

分 类 号：TN386.1[电子电信—物理电子学]