Electrical properties of crystalline YSZ films on silicon as alternative gate dielectrics

Crystalline yttria-stabilized zirconia oxide (YSZ) film was successfully de posited on a silicon wafer without an interfacial amorphous SiO2 layer. The film with equivalent oxide thickness t(eox) down to 1.77 nm shows negligib le hysteresis and low interface state density, less than 3 x 10(11) cm(-2) eV(-1). The leakage current density for t(eox) = 1.77 nm film, 1.5 x 10(-5) A cm(-2) at 1 V bias voltage, is five orders of magnitude lower than that for SiO2 with the same equivalent oxide thickness. The results demonstrate that an ultra-thin YSZ film has sufficient resistivity against the Formatio n of an underlying amorphous layer, and can be a promising gate dielectric replacing SiO2 to reduce the feature size of devices.