Neodymium (Nd)-doped Bi4Ti3O12 (Bi3.15Nd0.85Ti3O12, BNT) ferroelectric films have been deposited on Pt/Ti/SiO2/Si substrates by a sol-gel process and crystallized in nitrogen, air and oxygen environments, respectively. The crystallization environment was found to be important in determining the crystallization and ferroelectric properties of the BNT films. The film crystallized in nitrogen at a relatively low temperature of 650 degreesC, and exhibits excellent crystallinity and ferroelectricity with a remanent polarization of 2P(chi) = 63.6 muC/cm(2), a coercive field of 130 kV/cm and a fatigue-free characteristic. While the films annealed in air and oxygen, they did not show good crystallinity and ferroelectricity until they were annealed at 710 and 730 degreesC, respectively. A correlation between the remanent polarization and dielectric constants of the BNT films has been observed. (C) 2004 Elsevier B.V. All rights reserved.