Study of switching behavior in Pb(Zr,Ti)O3 thin films using X-ray diffraction

Pb(Zr,Ti)O3 (PZT) thin films are being developed for use in optical and electronic memory devices. To study ferroelectric switching behavior, we have produced relatively untextured PZT thin films on Si substrates. We have developed a method for using x-ray diffraction to observe domain switching in situ. Our study involved the use of a micro-diffractometer to monitor the switching behavior in relatively small (0.7 mm diameter) electroded areas. Diffraction analyzes were done while DC voltages were applied and removed, representing several places in the hysteresis loop. In particular, we were looking for relative intensity changes in the [h 00],[00l] diffraction peaks as a function of position in the hysteresis loop. Our study indicates that the 90° domain switching exhibited by bulk ferroelectrics, is very limited in films on Si when grain sizes are less than about 1 μm.