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

Abstract

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

The Separation Improvement in Transferring GaAs Solar Cell on Copper Tungsten

“…The dissolved layers, such as aluminum arsenide (AlAs) or aluminum nitride (AlN), also called sacrifice layer for its high etch selectivity, played key roles in the ELO process. [9][10][11][12] Here, we used AlAs as the sacrifice layer and hydrofluoric (HF) mixture etchant to transfer epilayers to the carrier substrate.…”