An improved SOI trench LDMOST with double vertical high-k insulator pillars  

作　　者：Huan Li Haimeng Huang Xingbi Chen 

机构地区：[1]State Key Laboratory of Electronic Thin Films and Integrated Devices of China, University of Electronic Science and Technology of China

出　　处：《Journal of Semiconductors》2018年第9期61-66,共6页半导体学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.51237001,51607026);the Fundamental Research Funds for the Central Universities(No.ZYGX2016J048)

摘　　要：An SOI trench LDMOST（TLDMOST）with ultra-low specific on-resistanceis proposed.It features double vertical high-k insulator pillars（Hk1 and Hk2）in the oxide trench,which are connected to the source electrode and drain electrode,respectively.Firstly,under reverse bias voltage,most electric displacement lines produced by the charges of the depleted drift region in the source side go through the Hk1,and thus the average electric field strength under the source can be enhanced.Secondly,two additional electric field peaks are induced by the Hk_1,which further modulate the electric field in the drift region under the source.Thirdly,most electric displacement lines produced by the charges of the depleted drift region in the drain side enter into the Hk2.This not only introduces one more electric field peak at the corner of the oxide trench around the Hk2,but also forms the enhanced vertical reduced surface field effect,which modulates the electric field in the drift region under the drain.With the effects of the two Hk insulator pillars,the breakdown voltage（BV）and the drift region doping concentration are significantly improved.The simulation results indicate that compared with the oxide trench LDMOST（previous TLDMOST）with the same geometry,the proposed double Hk TLDMOST enhances the BV by 86%and reduces theby 88%.An SOI trench LDMOST（TLDMOST）with ultra-low specific on-resistanceis proposed.It features double vertical high-k insulator pillars（Hk1 and Hk2）in the oxide trench,which are connected to the source electrode and drain electrode,respectively.Firstly,under reverse bias voltage,most electric displacement lines produced by the charges of the depleted drift region in the source side go through the Hk1,and thus the average electric field strength under the source can be enhanced.Secondly,two additional electric field peaks are induced by the Hk_1,which further modulate the electric field in the drift region under the source.Thirdly,most electric displacement lines produced by the charges of the depleted drift region in the drain side enter into the Hk2.This not only introduces one more electric field peak at the corner of the oxide trench around the Hk2,but also forms the enhanced vertical reduced surface field effect,which modulates the electric field in the drift region under the drain.With the effects of the two Hk insulator pillars,the breakdown voltage（BV）and the drift region doping concentration are significantly improved.The simulation results indicate that compared with the oxide trench LDMOST（previous TLDMOST）with the same geometry,the proposed double Hk TLDMOST enhances the BV by 86%and reduces theby 88%.

关 键 词：breakdown voltage HIGH-K specific on-resistance trench LDMOST 

分 类 号：TN386[电子电信—物理电子学]