Damage-Free Transfer of GaN-Based Light-Emitting Devices and Reuse of Sapphire Substrate. (10th August 2020)

• Record Type: Journal Article
• Authors: Zhang, Baoguo; Luo, Chao; Li, Yun-Fei
• Is Part Of: ECS journal of solid state science and technology. Volume 9:Number 6(2020)
• Publication Date: 2020-08-10
• Subjects: GaN, gallium nitride -- CMP -- laser lift-off -- patterned sapphire substrate -- LEDs; Solid state chemistry -- Periodicals; Electronics -- Materials -- Periodicals; Electrochemistry -- Periodicals; 541.0421
• DOI: 10.1149/2162-8777/aba7fc
• Languages: English
• ISSNs: 2162-8777

Abstract

Abstract : Gallium nitride (GaN) based semiconductors have been gaining worldwide attention in optoelectronics application, notably information displays and solid-state lighting. GaN light-emitting diodes (LEDs) epilayers are typically grown on sapphire substrates with metal-organic chemical vapor deposition (MOCVD) technique due to the absence of native nitride substrates. In this paper, the mesh-patterned sapphire substrates are fabricated to speed up the laser lift-off efficiency for the separation of GaN films from sapphire substrates. Damage-free GaN thin films fabricated on the sapphire substrates were successfully released and transferred onto Si substrates with sufficient quality through a Ti/Pt/Au/In bonding and subsequent laser lift-off processes. The GaN film mounted on Si substrates exhibits almost no attenuation in PL intensity before and after its transfer. The released sapphire substrate can be reprocessed by annealing & chemical mechanical polishing (CMP) process for reuse as epitaxial substrate with considerable cost reduction, featuring a comparable photoluminescence performance with fresh sapphire substrates.