Ti-precoating Effect on Wetting and Joining of Cu to SiC

抄録

The wettability of molten Cu on ti-precoating SiC was evaluated by a sessile drop technique. Titanium was coated by RF magnetron sputtering in argon gas. The contact angle of copper was measured by photography at 1 373 K in a vacuum. The equilibrium contact angle of copper on SiC was improved by increasing Ti precoating thickness. The Ti-precoating improves the wetting of copper on SiC. The formation of carbide and silicide such as TiC and Ti₅Si₃ at Cu/SiC interface accounts for the good wetting of copper on SiC.
The joining strength of copper with SiC was measured by fracture shear loading after joining copper to molybdenum. The joining strength of copper exhibits the maximum 10 μm of Ti thickness. The excess amounts of carbide and silicide cause the degradation of copper near the interface of Cu/SiC, though the formation of the compounds improve the wetting of copper. This is attributable to the maximum of joining strength of copper-metallized layer on SiC.