A novel organic coating assisted laser drilling method for TSV fabrication

作者:Mai Xiquan; Chen Yun; Shi Dachuang; Xun Chen; Xin Chen; Gao Jian; Cui Chengqiang; He Yunbo; Wong Ching Ping
来源:19th International Conference on Electronic Packaging Technology, ICEPT 2018, 2018-08-08 To 2018-08-11.
DOI:10.1109/ICEPT.2018.8480753

摘要

Through-silicon vias (TSVs) is a promising three-dimensional packaging solution in post-Moore's law era in the semiconductor industry. The fabrication of through silicon via plays an important role in three-dimensional packaging. Laser drilling is widely used in TSVs fabrication. However, the geometry quality of laser drilling is unsatisfied and heat affected zone (HAZ) is intrinsic. In this work, a novel organic coating assisted picosecond UV laser drilling method is proposed to obtain high-quality TSVs, the HAZ was noticeably eliminated and the TSVs quality was significantly improved. The effects of the organic thickness and laser power on the TSVs'quality were also studied in detail. It is found that the diameter of vias decreases with the increase of the organic thickness and decrease of the laser power. The minimum diameter of TSV obtained by this method is about 15 μm while the aspect ratio is beyond 30. Most importantly, by coating with the organic layer, the minimized via diameter can be decreased to about only 70% of the laser spot size which breaks the limit that the minimized via should be larger than or at least equal to the laser spot size. These findings will be helpful for TSV technology development in modern three-dimensional packaging.

  • 出版日期2018

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