深硅杯湿法腐蚀中金属保护工艺研究

A Novel Method for Metal Pattern Protection in Silicon Wet Etching Process

提出了一种新的采用聚酯胶膜保护金属图形的硅湿法腐蚀工艺,解决了深硅杯湿法腐蚀中金属保护难题,允许在器件完成所有IC工艺后再进行深硅杯湿法腐蚀。通过工艺试验研究,增加贴膜前的预处理和贴膜后的热压等工艺,能够有效延长掩膜的保护时间,在TMAH湿法腐蚀工艺条件下掩膜能够坚持6h,且成功实现了对硅280μm的深刻蚀。新工艺与IC工艺兼容,简单可靠,也能进行圆片级批量腐蚀。

A novel silicon wet etching process using polyester film was presented to protect patterned metal structures,which overcome the difficulty of metal protection,permitting the etching process proceed after all of the IC processes.It is demonstrated experimentally that the protection of polyester film for patterned metal can be prolonged efficiently by the processes such as the pretreatment before film pasting and the heat pressing after film pasting,etc.The optimized polyester film can survive 6hours in TMAH etchant,enabling 280μm deep etching of silicon.The process is reliable and easy to implement,which is compatible with conventional IC processes and suitable for mass production in wafer level.