Low temperature ISSG oxidation and its application in SSRW for 20nm and below semiconductor devices

Abstract

This paper investigates low temperature in situ steam generation (ISSG) oxidation, the correlation between the thickness growth rate and temperature, pressure, hydrogen flow and oxidation time. For low temperature ISSG oxidation, the within wafer uniformity is improved by increasing the temperature. An optimum pressure is revealed for all the possible hydrogen concentrations studied in this paper. However, the hydrogen flow itself exhibits a much more complicated relationship with the uniformity than that of temperature and pressure. Good uniformity is achieved through process optimization. It is found that the low temperature ISSG process exhibits a more robust within wafer uniformity than typical high temperature ISSG process due to the fact that the former one has better resistance to pressure and gas flow disturbance. One of the advantages that low temperature ISSG can enable SSRW application in 20nm semiconductor devices is also discussed in this paper.