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

Abstract

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)

Filling of porous silicon with magnetic materials

“…For example, it has been investigated with respect to forming adhesive metal layers on a silicon substrate. Since it is difficult to obtain adhesive metal films on bare silicon substrates, nanoporous silicon has been used, acting as a catalyst for the electroless metal deposition [34]. Ni deposition has been performed within porous silicon, offering pores with an aspect ratio of about 200, where the deposition has been controlled by the plating bath chemistry and the reaction time [35].…”

Noble Metal Recovering by Electroless Displacement Deposition on Silicon Powder

“…The demand for recycling these noble metals is also expected to increase. We previously studied the electroless displacement deposition of noble metal on silicon (Si) substrates (6-10) and reported it for preparation of Au, Ag, Pt, Pd, and Rh nanoparticles on Si (11,12), and application for efficient solar cell production (13)(14)(15) and metal film formation (16,17). This deposition is a local galvanic reaction expressed by the following: In this study, we applied electroless displacement deposition on Si for recovering noble metals from aqueous solutions.…”