A femtosecond laser focused inside bulk GaN was used to slice a thin GaN film with an epitaxial device structure from a bulk GaN substrate. The demonstrated laser slicing lift-off process did not require any special release layers in the epitaxial structure. GaN film with a thickness of 5 μm and an InGaN LED epitaxial device structure was lifted off a GaN substrate and transferred onto a copper substrate. The electroluminescence of the LED chip after the laser slicing lift-off was demonstrated.
@article{arxiv.1902.06348,
title = {Laser slicing: a thin film lift-off method for GaN-on-GaN technology},
author = {Vladislav Voronenkov and Natalia Bochkareva and Ruslan Gorbunov and Andrey Zubrilov and Viktor Kogotkov and Philipp Latyshev and Yuri Lelikov and Andrey Leonidov and Yuri Shreter},
journal= {arXiv preprint arXiv:1902.06348},
year = {2019}
}