Preparation and dielectric properties of polycrystalline films with dense nano-structured BaTiO3 by chemical vapor deposition using inductively coupled plasma

To clarify the dielectric properties of BaTiO3 with nanometer size region, it is necessary to fabricate the dense structure composed of BaTiO3 nanoparticles. In the present study, BaTiO3 nanoparticles were directly deposited on Pt/Al2O3/SiO2/Si substrate by introducing Ba(DPM)2 and Ti(OiPr)4 into an inductively coupled plasma (ICP). The optimal condition for preparing dense structure of BaTiO3 nanoparticles was investigated by changing the substrate temperature. Single phase BaTiO3 of perovskite structure was obtained at the substrate temperatures between 773 and 1173 K. The dense structure of BaTiO3 nanoparticles with particle sizes of about 30 nm was successfully obtained at the substrate temperature of 773 K. At the substrate temperature>873 K, the deposited nanoparticles sintered to be the columnar structure. The εr and tan δ of the BaTiO3 nanoparticles were estimated to be 285 and 6.6%, respectively (1 kHz and 100 mV). The phase of the BaTiO3 nanoparticles were found to be paraelectric by the measurement of C-V curves. The breakdown field of the dense structure of BaTiO3 nanoparticles was estimated to be 649 kV/cm according to I-V curves. These features are favorable for applying the structure to the dielectric layer of multilayer capacitors.