平面工艺功率型半导体晶体管铝迁移实验

Experiments of aluminum migration of power silicon transistor using planar process

在平面工艺制造的功率型半导体晶体管芯片表面,发现高强度电场条件下存在跨越0.05 mm半绝缘硅带的铝迁移现象,对此开展了一系列实验研究.通过开帽物理观察与分析、低温测试与烘干验证、迁移物质分析对比,确定了迁移现象中的迁移物质,同时分别取证环境温度、湿度、芯片表面污染物以及器件局部结构与此迁移现象的关联性,以此提出了迁移机理假说,为在不同的诱发条件下对此迁移机理进行确认和量化研究提供指导.

Experiments have been carried out on to study a phenomenon of aluminum migration across a 50 micron semi-insulation gap on the die surface of a power silicon transistor under a high-intensity electric field,which is manufactured using a typical planar process with aluminum as the metallization material.After physical observation and analysis by opening cap,testing at low temperature and validation by drying and analysis and comparison of composition in the migration,the chemical composition of the substances involved in the migration process was verified.Then the correlation between the migration process and environmental conditions of temperature and humidity,contaminants on the die surface as well as local structure of transistor were identified respectively.Based on the experiment results obtained in this study,a hypothesis was made on the mechanism of this migration phenomenon.The analysis provides direction for verification and quantization of the migration mechanism under different induced conditions.