β-Ga_(2)O_(3)SBD器件的解析模型与仿真研究

Analytical models and simulations analysis of β-Ga_(2)O_(3)Schottky barrier diodes

本文设计了不同电场调节策略的Ga_(2)O_(3)SBD器件,通过研究器件结构、钝化层方案下器件电学特性,分析不同终端结构(场板结构FP、边缘终端结构ET、沟槽型Trench、高K钝化)下Ga_(2)O_(3)SBD的结构设计.此外本文结合理论分析和实验数据拟合,完善了Ga_(2)O_(3)材料和器件模型,通过对比实验数据验证了模型的正确性.研究发现:(1)高K钝化(κ>100)结合场板结构可有效舒缓表面电场并提升结终端效率,2μm Ga_(2)O_(3)SBD采用BaTiO_(3)钝化场板可实现终端效率91.4%,V_(br)=1.43 kV,巴利加优值BFOM=1.62 GW/cm^(2),七倍于Al2O_(3)FP SBD;(2)采用BaTiO_(3)钝化的FP&ET复合终端可实现终端效率93.6%,V_(br)=1.46 kV,BFOM=0.41 GW/cm^(2);(3)相较FP设计,SiO_(2),Al2O_(3),HfO_(2)钝化的FP&Trench SBD更适于改善SBD导通电阻Ron,sp,V_(br)及BFOMs.上述研究为优化Ga_(2)O_(3)功率器件性能提供了理论依据和参考.

The device performance ofβ-Ga_(2)O_(3)Schottky barrier diodes(SBDs)with various structures is investigated using technology computer-aided design simulation.To mitigate field crowding at the electrode edge,three field management strategies(field plate(FP),trench anode,implanted edge termination(ET),using various passivation,such as SiO_(2),Al2O_(3),HfO_(2),BaTiO_(3))are investigated.After reviewing various models and parameters in the present literature,calibrated models for technology computer-aided design simulation ofβ-Ga_(2)O_(3)power SBDs are established.Highpermittivity(κ>100)FPs effectively smooth the surface field and improve termination efficiency.β-Ga_(2)O_(3)SBDs with a 2-μm drift layer and BaTiO_(3)FPs provide high termination efficiency(η=91.4%),breakdown voltage(V_(br)=1.43 kV),and reasonable BFOM(1.62 GW/cm^(2),7 times of FP SBDs using Al2O_(3)).Additionally,FP&ET with BaTiO_(3)provide maximum V_(br)(V_(br)=1.46 kV)and high termination efficiency(η=93.6%)with comparable BFOM(0.41 GW/cm^(2)).Furthermore,when compared with FP-SBDs,FP&Trench SBDs with SiO_(2),Al2O_(3),and HfO_(2)can improve Ron,sp,V_(br),and BFOMs.All of these provide theories and references for optimizing Ga_(2)O_(3)device performance in the future.