Au-Au Wafer Bonding in Vertical-structure GaN LED Fabrication

摘要

Metallic bonding including Au-Au, Au-Si, Al-Al and Al-Si bonding were attempted, and the Au-Au diffusion bonding with the best interface quality and nearly 100% bonded area was used to fabricate the vertical InGaN-GaN light-emitting diodes (LEDs) on 50-mm Si substrate. After the wafer bonding, a KrF excimer laser was used to separate the GaN layer from the grown sapphire substrate. The underlying mechanisms in above metallic bonding pairs were investigated by SAM (Scanning acoustic micrographs) and SEM (Scanning electron microscope).