LOW-TEMPERATURE SYNTHESIS OF BATIO3 THIN-FILMS ON SILICON SUBSTRATES BY HYDROTHERMAL REACTION

Crystalline BaTiO3 thin films (0.2-1 mum) of dielectric constant 450-5 00 have been synthesized by the hydrothermal reaction of a titanium fi lm (approximately 1 mum thickness) deposited on a silicon substrate wi th Ba(OH)2 solution (concentration 0.4 M) in the temperature range 100 -200-degrees-C. The reaction of the silicon substrate with the Ti film was prevented by deposition of a buffer layer of amorphous TiC betwee n the Ti film and the Si substrate. The TiC not only prevented the dif fusion of Si through the Ti layer but also allowed some reaction betwe en itself and the Ti layer so that the adherence of the films was not degraded.