Temperature effect on the reliability of ZrO2 gate dielectric deposited directly on silicon

Temperature effect on the reliability of ZrO₂ gate dielectric has been presented. High effective voltage-ramp breakdown field was observed. The activation energy of temperature accelerated voltage-ramp breakdown calculated from Arrhenius plot indicates that the breakdown of ZrO₂ is less sensitive to temperature than a thermal oxide of similar electrical thickness. ZrO₂ films exhibit excellent TDDB characteristics with low charge trapping and no stress induced leakage current. The field and temperature acceleration for TDDB for the 15.8 Å capacitance equivalent oxide thickness (CET) ZrO₂ shows that the activation energy for TDDB falls into the range reported for oxide from 39 Å to 150 Å. It was found that the extrapolated 10-year lifetime operating voltage can be as high as -1.9 V, even at 150°C based on the “log(t_BD) vs E” extrapolation model for a film with a CET of 15.8 Å