Positive temperature coefficient of resistivity in thin films of barium titanate

One of the perspective directions in using positive temperature coefficient (PTC) thermistors is their application in surface heater in various electronic devices and integrated circuits. The special interest in this connection makes possible fabrication of thin film structures on the basis of materials with PTCR. In the given work a result of the investigation of Y–BaTiO3 thin films has been presented. Thin films have been deposited by RF-sputtering technique. Films had thickness of 1.5–2mm. Subsequent annealing was carried out to obtain polycrystalline films of a single phase. The temperature dependence of resistance of films has been investigated. The increase of the resistance were observed in the temperature range 50–80°C. The jump of the resistance in field of phase transition was 70%.