The ferroelectric properties of c-axis oriented Pb5Ge3O11 thin films prepared by metalorganic chemical vapor deposition

C-axis oriented ferroelectric Pb5Ge3O11 thin films were prepared on Pt/Ir-coated Si wafers by metalorganic chemical vapor deposition (MOCVD) and rapid thermal process annealing techniques. The films were specular and crack free and showed complete crystallization with c-axis orientation for growth temperatures between 500 and 550 degrees C. Good ferroelectric properties were obtained for a 150-nm-thick film with Pt/Ir electrodes: the remanent polarization (2P(r)) and coercive field (2E(c)) values were about 3.8 mu C/cm(2) and 93 kV/cm, respectively. The films also showed excellent fatigue characteristics: no fatigue was observed up to 1 x 10(9) switching cycles. The leakage current increased with increasing applied voltage, and is about 3.6 x 10(-7) A/cm(2) at 100 kV/cm. The dielectric constant showed behavior similar to most ferroelectric materials in that the dielectric constant changed with applied voltages. The maximum dielectric constant is about 45. High-quality MOCVD Pb5Ge3O11 films can be used for single transistor ferroelectric memory devices. (C) 1999 American Institute of Physics. [S0003-6951(99)04002-4].