皮秒雷射應用在三維晶片矽導孔及Low-k晶圓切割研究

A Study on picosecond laser technology on 3D IC TSV and Low-k wafer grooving

王辰譯(Chen-Yi Wang)

指導教授 ： 徐祥禎

共同指導教授 ： 吳士傑(Shih-Jeh Wu)

義守大學/理工學院/機械與自動化工程學系/碩士(2014年)

https://doi.org/10.6343/ISU.2014.00139

摘要

本研究主要探討皮秒雷射應用於矽導孔之製程，雷射使用皮秒等級的綠光雷射。厚度100 um的晶圓試片進行雷射穿孔加工，並著重於精密加工，以確認控制參數對材料所造成的影響，實驗的參數則有加工速度、加工刀數、加工能量。本文將針對上述三個參數，進行穿孔、熱燒結、孔洞大小、孔洞寬高比等，進行探討。在本研究中不斷的實驗獲得的結果，例如孔洞直徑越來越小、孔洞內無阻塞等，使得雷射矽導孔實現度大幅增加，期望對半導體產業界未來在3D IC製程有所幫助。
另外也做了45 nm製程Low-K晶圓試片的切割優化實驗，針對Low-K晶圓試片先以雷射做切割道，再用鑽石刀將試片切斷，目的是為了減少晶圓因為鑽石刀切割所產生的裂紋，影響晶圓裡內埋的導線通路，優化過後可以明顯的改善短路問題，對晶圓切割製程上有很大的助益。

關鍵字

皮秒雷射 ； 矽導孔 ； 雷射穿孔 ； Low-k晶圓 ； 切割道

並列摘要

The aim of this research is to study the formation of TSV (through silicon via) by picosecond laser. Wafer thickness is 100 um and laser engine is green series. Experimental works are focused on micro precision process to observe the effect of silicon wafer material after laser drill. Parameters used in this work are speed, path and power. The effect of thermal affected zone, recast. via diameter and aspect ratio have been observed. Preliminary results on laser drill demonstrate that a decrease in drilled via diameter and no residual remains in via would improve TSV formation technology. An improved laser TSV technology will contribute to 3D IC packaging in semiconductor industry in the near future.
Secondary, the optimization on laser grooving on 45 nm low-k wafer is conducted. The material used in scribe line in 45nm wafer comprises metal (copper), low-k (ceramics) and silicon. Traditional diamond cutter would result in micro-cracking and chipping on silicon die. Newly developed process is applied laser grooving in the first and follows by a diamond cutting. A series of experimental works has been conducted on laser grooving and the results can then be applied to the wafer saw process.

並列關鍵字

picosecond laser ； TSV(through silicon via) ； laser drilling ； Low-k wafer ； laser grooving

參考文獻

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