Structural, optical and electrical properties of high-k ZrO2 dielectrics on Si prepared by plasma assisted pulsed laser deposition

ZrO2 films were grown on p-type Si(100) using plasma assisted pulsed laser deposition and the electrical characteristics of the ZrO2 dielectrics incorporated in metal oxide silicon (MOS) capacitors were studied in combination with their structural and optical properties. The ZrO2 dielectric layers are of polycrystalline structure with a monoclinic phase and show good interfacial properties without obvious SiOx interface. The electrical performance of the capacitors exhibits typical MOS-type capacitance–voltage (C–V) and leakage current density–voltage (J–V) characteristics. Thermal annealing of the ZrO2 dielectrics results in an improvement in C–V and J–V characteristics and a reduction in C–V hysteresis without obvious introduction of leakage paths for the fabricated MOS capacitors. The dielectric constant was calculated to be 15.4 and the leakage current density was measured to be 6.7 × 10− 6 A/cm2 at a gate voltage of + 1.0 V for 900 °C annealed ZrO2 dielectric layers with an equivalent oxide thickness of 5.2 nm.

► We study the ZrO2 dielectrics prepared by plasma assisted pulsed laser deposition. ► The ZrO2 dielectric layers are of polycrystalline structure with monoclinic phase. ► The ZrO2 films show high optical transparency from ultraviolet to near infrared. ► Capacitors with ZrO2 show typical metal–oxide–silicon electrical characteristics. ► Annealing of ZrO2 results in an improvement in electrical characteristics.