Surface modification of SiC substrates via direct fluorination to promote adhesion of electroless-deposited Ni film

To improve the adhesion between a silicon carbide (SiC) substrate and an electroless-plated Ni film, this study focused on the modification of a SiC substrate via direct fluorination (using F-2 gas) at 100-300 ? and 380 Torr for 10-120 min. During fluorination, the surface topography of the samples changed markedly at temperatures > 200 ?. However, the SiC surface fluorinated at 200 ? adhered poorly to the electroless-plated Ni films because of the formation of hydrophobic layers such as those comprising CF2 and CF3 groups. At temperatures greater than 300 ?, CF4 gasification of hydrophobic groups occurred on the SiC surface. This resulted in a SiC substrate with high surface roughness and hydrophilicity that strongly adhered to an electroless-plated Ni film. When the reaction temperature was 300 ? and the reaction time was 30 min or longer, the plating adhered strongly to the substrate. The adhesion strength between the SiC substrate and the electroless-deposited Ni film could be enhanced by hydrophilizing and roughening the SiC substrate through direct fluorination with F-2.