High-capacitance metal-insulator-metal capacitors using amorphous Sm2Ti2O7 thin film

Amorphous Sm2Ti2O7 (SmT) films were investigated to assess their potential use in metal- insulator- metal (MIM) capacitors. A 72 nm thick SmT film showed a high capacitance density of 5.2 fF/mu m(2) with a low leakage current density of 0.12 nA/ cm(2) at 2.0 V. The capacitance density increased with decreasing film thickness to 8.18 fF/ mu m(2) for the 46 nm thick film. The 72 nm thick SmT film had small quadratic and linear voltage coefficients of capacitance of 158 ppm/ V-2 and - 283 ppm/ V, respectively, and a temperature coefficient of capacitance of 207 ppm/degrees C at 100 kHz. Overall, amorphous SmT films are good candidate materials for MIM capacitors. (c) 2007 The Electrochemical Society.