The improvement of pyroelectric properties of PZT thick films on Si substrate by TiOx barrier layer

The effects of TiOx diffusion barrier layer thickness on the microstructure and pyroelectric characteristics of PZT thick films were studied in this paper. The TiOx layer was prepared by thermal oxidation of Ti thin film in air and the PZT thick films were fabricated by electrophoresis deposition method (EPD). To demonstrate the barrier effect of TiOx layer, the electrode/substrate interface and Si content in PZT thick films were characterized by scanning electron microscope (SEM) and X-ray energy dispersive spectroscopy (EDS), respectively. The TiOx barrier thickness shows significant influence on the bottom electrode and the pyroelectric performance of the PZT thick films. The average pyroelectric coefficient of PZT films deposited on 400 nm TiOx layer was about 8.94 × 10−9 C/(cm2 K), which was improved by 70% than those without diffusion barrier layer. The results showed in this study indicate that TiOx barrier layer has great potential in fabrication of PZT pyroelectric device.

► Effects of TiOx thickness on PZT pyroelectric properties are studied.
► TiOx are prepared by thermal oxidation of melt Ti layer.
► At 750 °C sintering temperature, TiOx layers are significant in blocking Si diffusion.
► Pyroelectric coefficient of PZT thick films are enhanced by 70% with 400 nm TiOx thickness.
► Two diffusion barrier mechanisms are presented.