Metal black pattern formation on photofunctional ZnO thin films by electroless deposition

A novel method is presented for the preparation of patterned metallic black thin films under ambient pressure conditions and without the use of photoresist. This method makes use of the rough underside of a metal layer which was deposited on a ZnO thin film on a smooth glass substrate. This highly black metallic underside is achieved by controlling the surface texture of the ZnO thin film. The black pattern is prepared via a photopatterning method that was recently developed in our laboratory, in which a Pd-(0) pattern is first produced by the photocatalytic reaction of the ZnO film, and then a metal, e.g., Cu, is selectively electroless deposited on the patterned Pd-(0). The metal patterns produced in this fashion exhibit very high optical densities (greater than 4.0 for transmission density and greater than 1.8 for reflection density) and relatively high adhesive strength, which makes it possible to use this method to fabricate high quality black matrices for use in liquid crystal color displays at lower cost. (C) 1998 The Electrochemical Society, Inc. S1099-0062(97)12-108-3.