芯片真空金锡共晶焊接中的气压控制

Atmosphere Pressure Control in Vacuum Gold Tin Eutectic Soldering of Chip

真空共晶焊接是用真空共晶炉实现芯片与载体互连的一种重要的焊接工艺。对于需要共晶的芯片,其与载体间共晶焊接的空洞率会直接影响到芯片工作时的散热及其输出功率。重点针对无工装施加压力条件下真空共晶炉内抽真空、加压、泄压等工艺展开试验研究,分析不同的炉内气压与空洞率之间的关系。试验结果表明,在焊料熔化形成空洞时增加气压、在焊料凝固后排气降压,对降低焊接空洞率有明显改善。

Vacuum eutectic soldering is an important technology and process to realize the interconnection between die and carrier.For the chip that needs eutectic,the void ratio of eutectic soldering between the chip and the carrier will directly affect the heat dissipation and output power when the chip is working.In the process of vacuum eutectic soldering,without tooling pressure,the relationship between atmosphere pressure and void rate is analyzed by using vacuum eutectic furnace.It is found that in the vacuum soldering process,pressure is applied after solder melting and forming voids,and pressure is released after solder solidification,which can significantly reduce the void rate.