提高4H-SiC横向BJT电流增益的新思路  

A New Method of Improving the Current Gain of 4H-SiC Lateral BJTs

作　　者：邓永辉[1] 盛况[1] 谢刚[1] 

机构地区：[1]浙江大学电气工程学院,杭州310027

出　　处：《半导体技术》2013年第5期342-346,共5页Semiconductor Technology

基　　金：教育部高等学校博士学科点专项科研基金资助项目(20100101110056);浙江省自然科学杰出青年基金资助项目(R1100468)

摘　　要：为了获得4H-SiC横向BJT器件高耐压下的高电流增益,文中通过降低漂移区的掺杂浓度(NDRI),使得漂移区内靠近基极方向的电场强度降低,从而使集-基结在基区的耗尽大幅减小。通过对基区的优化,就可以在高耐压下获得高电流增益。仿真结果表明,当漂移区内的掺杂浓度(NDRI)为3.3 1016cm-3时,4H-SiC横向BJT器件可以在保持较高耐压(3 000 V以上)的同时,集-基结在基区的耗尽最少。当基区掺杂浓度(PB)为3 1017cm-3、厚度(WB)为0.25 mm时,获得耐压高于3 000 V、电流增益近400的4H-SiC横向BJT器件。To obtain high current gain of4H-SiC lateral bipolar junction transistor （BJT） with high breakdown voltage, a new method of achieving current gain was presented and confirmed by simulations. By decreasing doping concentration （NDRI） in the drift region of 4H-SiC lateral BJT, electric field at the base side of the drift region was lowed and collector-base junction depletion extension in the base region was suppressed. Therefore, a high current gain can be obtained by optimization of the base width （ WB ） and doping （PB） respectively. Simulation results show that when NDRI i8 decreased to 3.3 ×10^16cm^-3, collector-base junction depletion extends in the base region least. And when with optimized Ws of 0.25μm and PB of 3 ×10^17cm^-3, current gain of the 4H-SiC lateral bipolar junction transistor current gain close to 400 is achieved with breakdown voltage more than 3 000 V.

关 键 词：4H-SIC 横向BJT 电流增益 击穿电压 漂移区 

分 类 号：TN304.24[电子电信—物理电子学] TN32