Pulsed laser deposition of ferroelectric bismuth titanate

Stoichiometric bismuth titanate films were prepared on MgO, Si, and Pt-coated Si by the technique of pulsed excimer laser deposition. This technique is a high-energy process with the potential to form the ferroelectric phase at a lower temperature than by sputtering. Fiber textured films were obtained on MgO [110] with preferred c-axis orientation. Polycrystalline films were obtained on Si [100] and Pt-coated Si at a temperature as low as 500 degrees C. The estimated saturation polarization and coercive field measured for the films were 28.0 mu C/cm/sup 2/ and 200 kV/cm, respectively. Also important from an integrated silicon device point of view, the as-deposited films had few particulates and were crack-free without the need for a postdeposition anneal. Results of attempts to integrate the films prepared in this manner in a FET memory structure are outlined.<
>