The ruggedness of a superjunction metal-oxide semiconductor field-effect transistor （MOSFET） under unclamped inductive switching conditions is improved by optimizing the avalanche current path. Inserting a P-island ...The ruggedness of a superjunction metal-oxide semiconductor field-effect transistor （MOSFET） under unclamped inductive switching conditions is improved by optimizing the avalanche current path. Inserting a P-island with relatively high doping concentration into the P-column, the avalanche breakdown point is localized. In addition, a trench type P＋ contact is designed to shorten the current path. As a consequence, the avalanche current path is located away from the N＋ source/P-body junction and the activation of the parasitic transistor can be effectively avoided. To verify the proposed structural mechanism, a two-dimensional （2D） numerical simulation is performed to describe its static and on-state avalanche behaviours, and a method of mixed-mode device and circuit simulation is used to predict its performances under realistic unclanlped inductive switching. Simulation shows that the proposed structure can endure a remarkably higher avalanche energy compared with a conventional superjunction MOSFET.展开更多
The repetitive unclamped inductive switching(UIS)avalanche stress is conducted to investigate the degradation and breakdown behaviors of conventional shield gate trench MOSFET(C-SGT)and P-ring SGT MOSFETs(P-SGT).It is...The repetitive unclamped inductive switching(UIS)avalanche stress is conducted to investigate the degradation and breakdown behaviors of conventional shield gate trench MOSFET(C-SGT)and P-ring SGT MOSFETs(P-SGT).It is found that the static and dynamic parameters of both devices show different degrees of degradation.Combining experimental and simulation results,the hot holes trapped into the Si/SiO_(2) interface and the increase of crystal lattice temperature should be responsible for the degradation and breakdown behaviors.Moreover,under repetitive UIS avalanche stress,the reliability of P-SGT overcomes that of C-SGT,benefitting from the decreasing of the impact ionization rate at bottom of field oxide caused by the existence of P-ring.展开更多
As a type of charge-balanced power device,the performance of super-junction MOSFETs(SJ-MOS)is significantly influ-enced by fluctuations in the fabrication process.To overcome the relatively narrow process window of co...As a type of charge-balanced power device,the performance of super-junction MOSFETs(SJ-MOS)is significantly influ-enced by fluctuations in the fabrication process.To overcome the relatively narrow process window of conventional SJ-MOS,an optimized structure"vertical variable doping super-junction MOSFET(VVD-SJ)"is proposed.Based on the analysis using the charge superposition principle,it is observed that the VVD-SJ,in which the impurity concentration of the P-pillar gradually decreases while that of the N-pillar increases from top to bottom,improves the electric field distribution and mitigates charge imbalance(CIB).Experimental results demonstrate that the optimized 600 V VVD-SJ achieves a 35.90%expansion of the pro-cess window.展开更多
基金supported by the National Key Scientific and Technological Project (Grant No. 2011ZX02503-005)the Fundamental Research Funds for the Central Universities, China (Grant No. ZYGX2010J038)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20110185120005)
文摘The ruggedness of a superjunction metal-oxide semiconductor field-effect transistor （MOSFET） under unclamped inductive switching conditions is improved by optimizing the avalanche current path. Inserting a P-island with relatively high doping concentration into the P-column, the avalanche breakdown point is localized. In addition, a trench type P＋ contact is designed to shorten the current path. As a consequence, the avalanche current path is located away from the N＋ source/P-body junction and the activation of the parasitic transistor can be effectively avoided. To verify the proposed structural mechanism, a two-dimensional （2D） numerical simulation is performed to describe its static and on-state avalanche behaviours, and a method of mixed-mode device and circuit simulation is used to predict its performances under realistic unclanlped inductive switching. Simulation shows that the proposed structure can endure a remarkably higher avalanche energy compared with a conventional superjunction MOSFET.
基金Project supported by the National Natural Science Foundation of China(Grant No.61504049)Jiangsu Province Postdoctoral Science Foundation(Grant No.2018K057B)the Fundamental Research Funds for the Central Universities,China(Grant No.JUSRP51510).
文摘The repetitive unclamped inductive switching(UIS)avalanche stress is conducted to investigate the degradation and breakdown behaviors of conventional shield gate trench MOSFET(C-SGT)and P-ring SGT MOSFETs(P-SGT).It is found that the static and dynamic parameters of both devices show different degrees of degradation.Combining experimental and simulation results,the hot holes trapped into the Si/SiO_(2) interface and the increase of crystal lattice temperature should be responsible for the degradation and breakdown behaviors.Moreover,under repetitive UIS avalanche stress,the reliability of P-SGT overcomes that of C-SGT,benefitting from the decreasing of the impact ionization rate at bottom of field oxide caused by the existence of P-ring.
基金supported by the National Science Foundation of Guangdong Province under Grant 2023A1515012652School-enterprise cooperation projects of ZTE Corporation.
文摘As a type of charge-balanced power device,the performance of super-junction MOSFETs(SJ-MOS)is significantly influ-enced by fluctuations in the fabrication process.To overcome the relatively narrow process window of conventional SJ-MOS,an optimized structure"vertical variable doping super-junction MOSFET(VVD-SJ)"is proposed.Based on the analysis using the charge superposition principle,it is observed that the VVD-SJ,in which the impurity concentration of the P-pillar gradually decreases while that of the N-pillar increases from top to bottom,improves the electric field distribution and mitigates charge imbalance(CIB).Experimental results demonstrate that the optimized 600 V VVD-SJ achieves a 35.90%expansion of the pro-cess window.
