Application of Diamond/Al in Microwave Power Modules

Aiming at the application requirements for advanced thermal management materials such as diamond/Al of power amplifier chips in high power microwave modules, preparation of solderable coating on diamond/Al surface and the Au80Sn20 automatic eutectic welding of power amplifier chip are studied in this paper. The heat dissipation test samples are prepared and the actual heat dissipation effect of both diamond/Al and MoCu is tested under operating conditions. The result shows that the Ni/Au coating plated on the surface of diamond/Al is uniform and compact and has good adhesion strength and solderability and the solder is well laid on the surface with soldering rate higher than 90%; that compared with MoCu, diamond/Al has better heat dissipation performance in the same condition for the highest temperature on the surface of diamond/Al decreases by 6.3 ℃ on average.