Practical high precise and efficient micromachining can be realized with computer controlled ultrashort laser pulses suppressing the thermal diffusion effect inside the material to be ablated. A direct translation from solid to the vapor state takes place at sufficient intensity levels. Experimental results of micromachining of different materials with femtosecond laser pulses at wavelengths of 800 nm and 267 nm from a commercial Ti:sapphire laser are presented. Holes down to a diameter below 1 micron have been drilled with 800 nm pulses into aluminum as an interesting metal with an absorption peak in the IR-range nearby 800 nm. Because of their low energy band gap semiconductors have a strong absorption at UV wavelengths. Arrays of holes down to 1 micrometer in diameter have been drilled into silicon and InP using 267 nm pulses. Results of fused silica as an example for transparent insulator materials are compared to result of semiconductors. The hole array manufacturing process takes only a few seconds. Precision can be improved by matching laser parameters to the processed material.

Date Published: 15 July 1999
PDF: 8 pages
Proc. SPIE 3618, Laser Applications in Microelectronic and Optoelectronic Manufacturing IV, (15 July 1999); doi: 10.1117/12.352676

Published in SPIE Proceedings Vol. 3618:
Laser Applications in Microelectronic and Optoelectronic Manufacturing IV
Jan J. Dubowski; Henry Helvajian; Ernst-Wolfgang Kreutz; Koji Sugioka, Editor(s)