Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5354146 | Applied Surface Science | 2016 | 31 Pages |
Abstract
Selective laser lift-off (SLLO) is an innovative technology used to manufacture and repair micro-light-emitting diode (LED) displays. In SLLO, laser is irradiated to selectively separate micro-LED devices from a transparent sapphire substrate. The light source used is an ultraviolet (UV) laser with a wavelength of 266Â nm, pulse duration of 20Â ns, and repetition rate of 30Â kHz. Controlled adhesion between a LED and the substrate is key for a SLLO process with high yield and reliability. This study examined the fundamental relationship between adhesion and laser irradiation. Two competing mechanisms affect adhesion at the irradiated interface between the GaN LED and sapphire substrate: Ga precipitation caused by the thermal decomposition of GaN and roughened interface caused by thermal damage on the sapphire. The competition between these two mechanisms leads to a non-trivial SLLO condition that needs optimization. This study helps understand the SLLO process, and accelerate the development of a process for manufacturing micro-LED displays via SLLO for future applications.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Junsu Park, Young-Gwan Sin, Jae-Hyun Kim, Jaegu Kim,