Wet processing for the fabrication of ceramic thin films on plastics

Development of a versatile technique for fabricating ceramic thin films on plastics has long been a challenge for those who aim at providing the surface of lightweight, flexible plastics a variety of functions. Wet processing techniques that have been reported so far on the fabrication of ceramic thin films on plastics are reviewed in this article. The techniques include crystalline nanoparticle deposition, liquid phase deposition, sol-gel method and chemical solution deposition (CSD). In these techniques, the issue of how to crystallize and/or densify the films on plastic substrates without firing has been focused on, and it would be recognized that great efforts have been made on this issue. Self-combustion of CSD thin films is also introduced, which only requires heat treatment at low temperatures for films to be crystallized. Finally a transfer process that our group has proposed recently is presented, which is unique in that the crystallization and densification are guaranteed by a firing step.