Sol-gel PTC BaTiO/sub 3/ thin films: application of PTC film to heater plate

摘要

PTC BaTiO/sub 3/ (BT) thin films were fabricated to apply to a heater plate. BT sol solutions composed of barium acetate and titanium-tetrabutoxide were prepared in a mixture of glycerine, methanol and acetic acid. The small amounts of donor (La), acceptor (Mn) and sintering aid (Si) were added to the BT sol solutions. In this study, we found out that the fabrication conditions of the sol-gel PTC BT thin films for heater devices were as follows: (1) the sol compositions available for PTC films, (2) the substrates which don't react with the films such as high purity BT ceramics, (3) relatively high firing temperatures to crystallize the tetragonal phase, (4) coarse grains (20-80 /spl mu/m), and (5) the film thickness of 2-4 /spl mu/m for the film heaters which showed high response to temperature change and uniform heating.