Tampere University of Technology

TUTCRIS Research Portal

High speed, high strength microwelding of Si/glass using ps-laser pulses

Research output: Contribution to journalArticleScientificpeer-review


Original languageEnglish
Pages (from-to)3427-3439
Number of pages13
JournalOptics Express
Issue number3
Publication statusPublished - 9 Feb 2015
Publication typeA1 Journal article-refereed


A novel microwelding procedure to join Si-to-glass using pslaser pulses with high repetition rates is presented. The procedure provides weld joint with mechanical strength as high as 85 MPa and 45 MPa in sample pairs of Si/aluminosilicate (Si/SW-Y) and Si/borosilicate (Si/Borofloat 33), respectively, which are higher than anodic bonding, at high spatial resolution (< 20 μm) and very high throughput without pre- and post-heating. Laser-matter interaction analysis indicates that excellent weld joint of Si/glass is obtained by avoiding violent evaporation of Si substrate using ps-laser pulses. Laser welded Si/glass samples can be singulated along the weld lines by standard blade dicer without defects, demonstrating welding by ps-laser pulses is applicable to wafer-level packaging.

Publication forum classification

Field of science, Statistics Finland