New Surface-Activation Process for Electroless Deposition of Adhesive Metal Films on Silicon

硅表面的金纳米颗粒不仅可以作为引发自催化化学金属沉积的催化剂，还可以作为沉积金属膜与硅表面的结合点。金纳米颗粒可以不经任何处理直接在硅平面上形成金属薄膜。透射电镜观察表明，金纳米颗粒在室温下与硅形成合金。这种合金提高了金属薄膜在硅上的附着力。利用光刻胶图案和本发明的电镀方法，在硅表面形成了几十微米尺度的清晰的金属图案。化学沉积的金属膜与硅的接触电阻率与传统金属化方法的接触电阻率一样低。

Gold nanoparticles on silicon work not only as catalysts to initiate autocatalytic electroless metal deposition but also as binding points between the deposited metal film and the silicon surface. Gold nanoparticles can directly produce adhesive metal films on flat silicon surfaces without any treatments. Crosssectional transmission electron microscopic observation reveals that gold nanoparticles form an alloy with silicon at the room temperature. This alloy improves the adhesion of metal film on silicon. A sharp and clear metal pattern in tens-micron-scale was formed on the silicon surface by using a photoresist pattern and the present plating method. The contact resistivity between the electrolessly deposited metal film and silicon was as low as that for the conventional metallization methods.