Simple Low-Temperature GaN/Diamond Bonding Process with an Atomically Thin Intermediate Layer
Takashi Matsumae, Sho Okita, Shoya Fukumoto, Masanori Hayase, Yuichi Kurashima, Hideki Takagi
Abstract
High Resolution Image Download MS PowerPoint Slide We demonstrated the low-temperature bonding of GaN and diamond substrates using wet chemical treatments. The GaN and diamond surfaces treated with HCl and NH 4 OH/H 2 O 2 solutions, respectively, could adhere to each other by contact under atmospheric conditions. After annealing at 200 °C, they were bonded with a shear strength of 8.19 MPa. Interfacial observations revealed that the GaN and diamond crystallines were bonded through an ∼3 nm-thick amorphous layer consisting of Ga, O, and sp 2 -C. The proposed bonding process consists of wet chemical treatment followed by low-temperature annealing under atmospheric conditions. As this simple process enables GaN/diamond integration without adhesive layers, it would contribute to future high-power and high-frequency GaN devices integrated on the diamond heat spreader.