Pulsed laser activation and electroless metallization of SiC single crystal

Abstract

A novel approach to the metallization of silicon carbide single crystal is examined. It is shown that the activation of SiC single crystal for electroless metal plating is possible via laser ablation. The ablated areas of SiC are covered by metal upon dipping the sample into an aqueous electroless solution. The electrolessly deposited Ni and Cu show the ohmic contact to n-SiC without any auxiliary annealing. The ablation of SiC under nanosecond duration laser pulses is uncongruent, and the Raman analysis reveals the formation of Si clusters of 10-20 nm character size on SiC surface under laser ablation in air and in vacuum. The ability of the ablated SiC areas to reduce metal from its electroless solution is assigned to the residual modifications of its band structure within the ablated areas. Spatial resolution of the metallization method is about 1 /spl mu/m and can be improved using shorter laser wavelengths and fine optics.