The effect of microwave irradiation process on crystallization of Pb(ZrxTi1-x)O-3 (PZT) films was investigated. The PZT thin films were coated on Pt/Ti/SiO2/Si substrates by a sol-gel method and then crystallized by single-mode 2.45 GHz microwave irradiation in the magnetic field at 500 degrees C for 30 min and 650 degrees C for 60 s, respectively. The crystalline phases, microstructures and electrical properties of the PZT films are investigated. X-ray diffraction analysis indicated that both the films heated by microwave irradiation at 500 degrees C for 30 min and those at 650 degrees C for 60 s were crystallized well into the perovskite phase. However, the PZT films crystallized at 500 degrees C for 30 min had a (100)-preferred orientation while the PZT films crystallized at 650 degrees C for 60 s had a (111)-preferred orientation. The average values of remanent polarization, coercive field, dielectric constant and loss of the PZT films crystallized at 500 degrees C for 30 min are approximately 21 mu C/cm(2), 90 kV/cm, 510 and 0.07 respectively, whereas the PZT films crystallized at 650 degrees C for 60 s are approximately 27 mu C/cm(2), 82 kV/cm, 900 and 0.05 respectively. The difference between the electrical properties of the PZT films crystallized by deferent process can be related to the microstructure effect.