屏蔽栅沟槽MOSFET源-漏极间的漏电流优化  

Optimization of Source-Drain Leakage Current of Shield Gate Trench MOSFET

作　　者：余长敏 罗志永 刘宇 Yu Changmin;Luo Zhiyong;Liu Yu(Shanghai Huahong Grace Semiconductor Manufacturing Co.,Ltd.,Shanghai 201203,China)

机构地区：[1]上海华虹宏力半导体制造有限公司,上海201203

出　　处：《半导体技术》2023年第12期1092-1096,共5页Semiconductor Technology

摘　　要：对于功率MOSFET,在较大的外加电压下能否获得更小的源-漏极间漏电流是评价器件性能的重要指标之一。针对击穿电压150 V的屏蔽栅沟槽MOSFET源-漏极间漏电流过大的问题,提出了两种有效的优化方法,包括降低接触孔离子注入后快速退火温度及减薄接触孔钛黏合层的厚度。结合理论计算,从缺陷影响的角度分析了上述方法减小漏电流的原因。这两种方法降低了源区pn结附近的缺陷浓度,导致pn结的反偏产生电流减小,从而减小漏电流,有效改善了源-漏极间漏电流过大的问题,使产品成品率得到提高。For power MOSFETs,whether a smaller source-drain leakage current can be obtained at a high external voltage is one of the important indexes for evaluating device performance.To solve the problem of excessive source-drain leakage current of shield gate trench MOSFET with a breakdown voltage of 150 V,two effective optimization methods were proposed,including lowering the rapid annealing tem-perature after ion implantation and reducing the Ti adhesion layer thickness of contact hole.Combined with the theoretical calculation,the reasons for the reduction of leakage current via above methods were analyzed from the angle of influence of defects.By using these two methods,the defect concentration near pn junction in source region is reduced,resulting in a smaller reverse current generated by pn junction,thus reducing the leakage current and effectively solving the problem of large source-drain leakage cur-rent,which improves the yield of the product.

关 键 词：漏电流 击穿电压 接触孔 黏合层 离子注入 

分 类 号：TN386.1[电子电信—物理电子学] TN305