Characterization of ultrathin oxide prepared by low-temperature wafer loading and nitrogen preannealing before oxidation
- 15 August 1992
- journal article
- research article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 72 (4) , 1378-1385
- https://doi.org/10.1063/1.351749
Abstract
In this study, we report a high‐performance ultrathin oxide (≊80 Å) prepared by a low‐temperature wafer loading and N2 preannealing before oxidation. This recipe can reduce native oxide thickness and thermal stress compared to the conventional oxidation recipe. The high‐resolution transmission electron microscopy reveals that the SiO2/Si interface is atomically flat, and a thin crystalline‐like oxide layer about 7 Å exists at the interface. Oxides prepared by the proposed recipe show a very high dielectric breakdown field (≥16 MV/cm) and a very low interface state density (N it ≊ 3 × 109 eV−1 cm−2 at midgap). The effective barrier height at cathode derived from the slopes of log(J g /E 2 ox) vs 1/E ox and t bd vs 1/E ox plots is about 3.9 eV, instead of 3.2 eV for the control sample. It also shows a better immunity to the charge trapping and interface state generation under high‐field stressing, and superior time‐dependent dielectric breakdowncharacteristics.This publication has 19 references indexed in Scilit:
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