3300V碳化硅肖特基二极管及混合功率模块研制

基于数值仿真结果,采用结势垒肖特基(JBS)结构和多重场限环终端结构实现了3 300 V/50 A 4H-SiC肖特基二极管(SBD),所用4H-SiC外延材料厚度为35 μm、n型掺杂浓度为2× 1015cm-3.二极管芯片面积为49 mm2,正向电压2.2V下电流达到50 A,比导通电阻13.7 mΩ· cm2;反偏条件下器件的雪崩击穿电压为4 600 V.基于这种3 300 V/50 A 4H-SiC肖特基二极管,研制出3 300 V/600 A混合功率模块,该模块包含24只3 300 V/50 A Si IGBT与12只3 300 V/50 A 4H-SiC肖特基二极管,SiC肖特基二极管为模块的续流二极管.模块的动态测试结果为:反向恢复峰值电流为33.75 A,反向恢复电荷为0.807 μC,反向恢复时间为41 ns.与传统的Si基IGBT模块相比,该混合功率模块显著降低了器件开关过程中的能量损耗.

Development of 3 300 V SiC SBD and Hybrid Power Module

Based on the numerical simulation results,a 3 300 V/50 A 4H-SiC Schottky barrier diode (SBD) with junction barrier Schottky (JBS) structure and multiple field limiting ring (FLR)junction termination structure was achieved,which was fabricated on the 4H-SiC substrate with the epitaxial layer thickness of 35 μm and n-type doping concentration of 2×1015cm-3.The chip area is 49 mm2 and the current is 50 A at 2.2 V forward bias voltage,which indicates the specific on resistance of 13.7 mΩ · cm2;the avalanche breakdown voltage is 4 600 V under the reverse bias voltage.Based on the 3 300 V/50 A SBD diode,a 3 300 V/600 A hybrid module was developed,which includes 24 Si insulated gate bipolar transistor (IGBT) of 3 300 V/50 A and 12 SiC SBD diode of 3 300 V/50 A;the SiC SBD works as a free-wheeling diode in the hybrid module.The dynamic characteristic test results show that the reverse recovery peak current is 33.75 A,the reverse recovery charge is 0.807 μC,and the reverse recovery time is 41 ns.Compared with conventional Si IGBT power modules,the SiC hybrid power module reduces the energy loss greatly during the switching process of the devices.