漏电低软度大的4500 V FRD设计

4500 V FRD Chips with Low Leakage Current and Big Softness

为了满足4500 V快恢复二极管(Fast recovery diode,FRD)反向偏置漏电低、反向恢复软度大的应用要求,介绍了一种新的FRD设计方法。该设计通过优化阳极掺杂,采用轻离子辐照和电子辐照相结合的寿命控制方式来增加FRD的反向恢复软度,降低FRD的元胞漏电流,并通过台阶形场板保护环结构来降低保护环的漏电流。采用203.2 mm(8英寸)平面栅加工工艺制作芯片并封装成4500 V/3000 A FRD模块,模块在高温125℃下的正向压降为3.1 V,反向偏置漏电流为10 mA,反向恢复能量为5300 mJ,反向恢复软度为1.24,反向恢复电流下降速度为6000 A/μs时,承受的极限功率可达8 MW。

To meet the application requirement of 4500 V FRD with low reverse bias leakage current and big reverse recovery softness,a new FRD design was proposed.In the design,the soft-ness was increased and cell leakage current was reduced by optimizing anode doping and light ions irra-diation combined with electrons irradiation,the terminal leakage current was reduced by adopting the guard ring structure with stepped electric field plates.By adopting 8-inch planar gate process,FRD chips were fabricated and packaged to 4500 V/3000 A modules.The forward voltage(VF)of the modules is 3.1 V,reverse leakage current(IR)is 10 mA,and reverse recovery energy(Erec)is 5300 mJ,the reverse recovery softness is 1.24 and the maximum power is 8 MW when the reverse recovery current falling rate with time is 6000 A/μs at the temperature of 125℃.