Line beam processing for laser lift-off of GaN from sapphire
Article first published online: 10 OCT 2012
Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
physica status solidi (a)
Volume 209, Issue 12, pages 2653–2658, December 2012
How to Cite
Delmdahl, R., Pätzel, R., Brune, J., Senczuk, R., Goßler, C., Moser, R., Kunzer, M. and Schwarz, U. T. (2012), Line beam processing for laser lift-off of GaN from sapphire. Phys. Status Solidi A, 209: 2653–2658. doi: 10.1002/pssa.201228430
- Issue published online: 12 DEC 2012
- Article first published online: 10 OCT 2012
- Manuscript Accepted: 23 SEP 2012
- Manuscript Revised: 23 AUG 2012
- Manuscript Received: 27 JUN 2012
- laser lift-off;
Gallium nitride (GaN) layers grown on sapphire substrate wafers have been successfully separated using a novel line beam laser lift-off (LLO) approach. The absorption of the 248 nm excimer laser radiation by the GaN through the sapphire wafer results in the formation of metallic gallium and nitrogen gas. The sapphire wafer was easily removable by heating above the gallium melting point. The metallic gallium phase has been inspected via diverse microscopic surface analysis techniques after line beam LLO processing. The measurements indicate that the sapphire separation process using line beam laser scanning has only a marginal impact on the structural quality of the GaN layer. Line beam LLO processing has inherent upscaling advantages over conventional square field LLO. Processing results are evaluated in view of aptness for mass production of high brightness light emitting diodes (HB-LEDs).
Differential interference contrast image of GaN film after 248-nm LLO with line beam (A) and square beam (B).