InGaN-Based Light Emitting Diodes with an A1N Sacrificial Buffer Layer for Chemical Lift-Off Process

摘要

The InGaN-based light-emitting diodes (LEDs) grown on triangle-shaped patterned sapphire substrates were separated through a chemical lift-off process by laterally etching an A1N sacrificial layer at the GaN/sapphire substrate interface. The lateral etching rate of the A1N buffer layer was calculated at 10um/min for the 100μm-width LED chip that was lifted off from the sapphire substrate. A triangular-shaped hole structure and a hexagonal-shaped air-void structure were observed on the lift-off GaN surface that was transferred from the patterned sapphire substrate. The chemical lift-off process was achieved by using an A1N buffer layer as a sacrificial layer in a hot potassium hydroxide solution.