Electroless Deposition of Noble Metal Nano Particles as Catalyst and Subsequent Micropatterning of Silicon Substrate by Wet Chemical Etching

Noble metal particles such as Ag and Pd were deposited site-selectively on Si substrate using colloidal crystal composed of polystyrene spheres as a mask for electroless plating to obtain metallic honeycomb pattern. After metal-assisted chemical etching of Si in HF/H2O2, ordered Si convex arrays were formed. On the other hand, isolated-island metal pattern was obtained on Si substrate by hydrophobic treatment with colloidal crystal templating, which acted as a mask for subsequent electroless plating. Si hole arrays formed after chemical etching corresponded to inverse structure of above-mentioned Si convex arrays. The dimensions of the resultant pattern could be adjusted with feature sizes ranging from 3 µm to 200 nm by changing the diameter of the polystyrene spheres used as an initial mask.