表面活化处理在激光局部键合中的应用

为了研究低热应力键合工艺,提出了一种将表面活化直接键合与激光局部键合相结合的键合技术。首先采用RCA溶液对键合片进行表面亲水活化处理,并在室温下成功地完成了预键合。然后在不使用任何夹具施加外力辅助的情况下,利用波长1064nm、光斑直径500μm、功率70W的Nd:YAG连续式激光器,实现了激光局部键合,并取得了6.3MPa~6.8MPa的键合强度。结果表明,这种以表面活化预键合代替加压的激光局部键合技术克服了传统激光键合存在的激光对焦困难,以及压力不匀易损害键合片和玻璃盖板等缺点,同时缩短了表面活化直接键合的退火时间,提高了键合效率。

Application of surface activation in laser localized bonding

A new bonding technique to alleviate the high temperature adverse effect in silicon-glass bonding process was presented which combines the advantages of surface activated direct bonding and local laser bonding techniques. RCA solution was used to make the bonding surfaces hydrophilic and the silicon-glass prebonding was accomplished at room temperature. The laser with a wavelength of 1064nm was used and its spot diameter was 500~m and the power was 70W. Without any external pressure, the prebonded pairs were bonded locally and the bonding strength reaches 6.3MPa - 6.8Mpa. The experimental results of show that this bonding technique, which employs surface activated prebonding to substitute pressure to maintain the intimate contact of bonding chips ,has overcome the disadvantages that focusing is difficult and bonding chips and glass cover are easy to broken in normal local laser bonding processing. This technique also improves the efficiency of surface activated direct bonding by shortening the annealing time.