Catalytic nanopores for electroless deposition of adhesive metal films on silicon: Applications to various silicon substrates including multi- and micro-crystalline

Metal-particle-assisted hydrofluoric acid etching of silicon (Si) is a unique method of preparing Si nanopores with metal nanoparticles at the bottom of each nanopore. Autocatalytic electroless deposition, which is the conventional method to metalize nonmetallic substrates, requires catalyzation of the substrates before deposition. For Si substrates, obtaining adhesive metal films with conventional catalyzation pretreatments is difficult. We recently developed a new method to produce adhesive metal films on Si substrates using catalytic nanopores that consists of three steps: 1) displacement deposition of metal nanoparticles; 2) Si nanopore formation by metal-particle-assisted hydrofluoric acid etching; and 3) autocatalytic electroless deposition of metal films. In this study, the new method is applied not only to previously reported p-Si (100) 1 Ω cm substrates but also to various Si substrates, such as low and high resistibility, p- and n-types, (100), (111), and (110) planes, and single-, multi- and micro-crystalline substrates. Adhesive and bright metal films were formed on all Si substrates. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)