Electrical characterizations of MgTiO3 thin films grown on Si

We have analyzed MgTiO3 thin films grown on the Si substrate with/without SiO2 using pulsed laser deposition (PLD). We find that MgTiO3 thin films start to crystallize at 600 degreesC, causing electrical instabilities in the MIS capacitors above this temperature. Detailed analysis by XRD technique reveals that structural differences of MgTiO3 thin films were not obvious below 600 degreesC, whereas the electrical characteristics changes as a function of deposition temperature and the presence of thermally grown SiO2. We observe that the decrease of deposition temperature results in the increase of leakage current and anomalous positive charge (APC) density. These drawbacks were effectively suppressed by growing 100 Angstrom SiO2 layer on the Si substrate prior to the deposition of MgTiO3 thin films.