Fabrication method of GaN template for high-speed chemical lift-off

Abstract

In this study, a gallium nitride (GaN) template fabrication method for efficient chemical lift-off (CLO) is developed. CLO is slower than other lift-off methods. An air tunnel structure is formed using a photoresist to reduce the process time and improve the etchant penetration rate. Furthermore, an aluminum nitride (AlN) sacrificial layer is mounted on a trapezoid-shaped patterned sapphire substrate. GaN epitaxial growth is observed on the AlN sacrificial layer. The basic physical properties of the grown GaN are investigated using x-ray diffraction, atomic force microscopy, and photoluminescence measurement. The GaN template with the air tunnel structure is depleted by CLO, and the peeling rate is found to be 2.3-6.45 times higher than that reported in the literature.