微模具重复利用的高深宽比铜微结构微电铸复制技术

Micro Electroforming Replication Technology with Reusable Micro Molds for High Aspect Ratio Copper Microstructure

针对紫外线光刻、电铸成型和注塑(UV-LIGA)工艺的去胶难题,提出了一种以脱模代替去胶的改良工艺,用于批量制造高深宽比铜微结构。该工艺以可重复利用的硅橡胶软模具代替传统的SU-8光刻微模具,采用硅通孔(TSV)镀铜技术进行微电铸填充,然后通过直接脱模实现金属微结构的完全释放,既解决了去胶难题,又能够解决高深宽比微模具电铸因侧壁金属化导致的空洞包夹问题,同时可以大幅降低成套工艺成本。仿真和实验结果显示,热处理可以改善脱模效果,显著降低脱模损伤,支持微模具重复利用。采用初步优化的改良工艺已成功实现深宽比约3∶1的铜微结构的高精度复制。

An improved process that employs mold release as a substitute for the debinding was proposed for the debinding challenges of the ultraviolet lithography,galvano-formung,abformung(UV-LIGA)process.And it can be applied for the batch production of copper microstructures with high aspect ratios.The process replaces conventional SU-8 photolithography micro-molds with reusable silicone rubber soft molds,and utilizes throughsilicon via(TSV)copper plating technology for micro-electroforming filling.Subsequently,the complete liberation of the metal microstructures was realized by direct mold release,thus solving the debinding challenges,addressing the issues of cavity entrapment due to sidewall metallization in galvano-formung process of high aspect ratio micro-molds,and meanwhile significantly reducing the cost of the overall process.Simulation and experimental results show that heat treatment can enhance the mold release effect,obviously reduce the mold release damage,and support the reuse of micro-molds.The improved process was preliminarily optimized,by which high-precision replication of copper microstructures with aspect ratio of about 3∶1 was successfully achieved.