Electrical and Structural Studies of Laser-debonded GaN Light Emitting Diodes

We report experimental investigation of laser-assisted debonding of GaN-based light emitting diodes grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrates. Transmission electron microscopy is employed to characterize the laser affected zone of the debonded LEDs. The findings from TEM studies are in good agreement with our thermal analysis predictions. The as-debonded surface is then roughened by photo-electro chemical (PEC) wet etching to form nano-scaled hexagonal pyramid structures and this morphology is found to be useful for light extraction on LEDs.