Free standing GaN nano membrane by laser liftoff method
Date of this Version8-26-2012
Liang Tang, Yuefeng Wang, Gary Cheng, Michael J. Manfra and Timothy D. Sands (2012). Free standing GaN nano membrane by laser liftoff method. MRS Proceedings,1432, mrss121432g0302 doi:10.1557/opl.2012.1054
In this work, we present a method able to fabricate thin GaN nanomembranes fit for device applications. Starting from commercial GaN on sapphire substrates, MBE was used to deposit a sacrificial layer, which comprises of a superlattice of InN/InGaN, after which thin a GaN film of hundreds of nanometers thickness was grown on top. Pulsed laser irridiation with photon energy of 2.3eV gives rise to the controlled decomposition of the sacrificial intermediate layer, which can be followed by easy separation of the top GaN membrane from the substrate. This process can be used to manufacture GaN membranes with low defect density and a wider range of thickness. We demonstrated that large area, free-standing GaN membranes, with a thickness from 200nm and up, could be made using this method, and the high crystal quality of the lift-off GaN layers is well preserved in this process.
Electronic Devices and Semiconductor Manufacturing | Energy Systems | Nanotechnology Fabrication