Development of SLID Bonding Technology for GaN Assembly Based on Ag Microflakes

This paper covers the main aspects of applying SLID (Solid Liquid InterDiffusion bonding) for assembly of GaN structures to DBC (Direct Bonded Copper) substrates with Sn metallization. The influence of GaN ohmic contact metallization, Sn thickness on DBC as well as bonding parameters (pressure, temperature, time) on adhesion of GaN structures to DBC substrate were investigated. It was found that the weakest points of adhesion are the interfaces between micro-Ag sintered layer and surfaces of GaN or DBC metallization. The cohesion of micro-Ag layer sintered at ${8}\ MPa/280^{\mathrm{o}}C$ exceeds ${20}\ MPa$.