Gd. Wilk et B. Brar, Electrical characteristics of high-quality sub-25-angstrom oxides grown byultraviolet ozone exposure at low temperature, IEEE ELEC D, 20(3), 1999, pp. 132-134
We have developed a method for controllably and reproducibly growing self-l
imiting ultrathin oxides with excellent electrical properties in the range
similar to 10-25 Angstrom thick at temperatures ranging from 25 to 600 degr
ees C, respectively, using an ultraviolet ozone (UVO3) oxidation process. T
he self-limiting thickness depends primarily on the substrate temperature,
allowing ultrathin oxide growth with precision and reproducibility using th
is UVO3 process. Oxides grown by this method are comparable in electrical q
uality to thermal oxides, with similar leakage current densities and breakd
own fields E-BD > 10 MV/cm. Current-voltage (I-V) analysis shows oxide thic
kness uniformity to within 1% from center to edge of a 4-in wafer. Capacita
nce-voltage (C-V) characterization of similar to 25 Angstrom oxides shows e
xcellent saturation behavior, with low midgap interface trap densities and
no hysteresis or dispersion.