Stable zirconium silicate gate dielectrics deposited directly on silicon
03 January 2000
Zirconium silicate (ZrSixOy) gate dielectric films with similar to 3-5 at. % Zr exhibit excellent electrical properties and high thermal stability in direct contact with Si. We demonstrate an equivalent oxide thickness of about 21 Angstrom for a 50 Angstrom ZrSixOy film sputter-deposited directly on a Si substrate, as measured by capacitance-voltage techniques, with a hysteresis shift less than 10 mV. Leakage currents for these films are very low, approximately 1 x 10(-6) A/cm(2) at 1.0 V bias in accumulation. Films ramped to hard breakdown exhibit breakdown fields E-bd similar to 10 MV/cm. Excellent electrical properties are obtained with Au electrodes, in particular. (C) 2000 American Institute of Physics. {[}S0003-6951(00)03101-6].