Print: | ISSN 0256-1115 |
Online: | ISSN 1975-7220 |
Korean Journal of Chemical Engineering,
Vol.16, No.1, 12-21, 1999 NUMERICAL AMALYSIS OF LPCVD OF SiO2 FILMS FROM DIETHYLSILANE/OXYGEN
A mathematical model has been developed to explore the low pressure chemical vapor deposition (LPCVD) of silicon dioxide from diethylsilane (DES)/oxygen in a horizontal hot-wall reactor. We propose a new kinetic mechanism that includes realistic gas-phase and surface reactions. The partial differential equations in two-dimensional cylindrical coordinates are solved numerically by a control-volume-based finite difference method. The model successfully describes the behavior of the experimental data. Film growth rate and uniformity are studied over a wide range of operating conditions including deposition temperature, pressure, reactant flow rate, and distance between the inlet and the wafer. The predicted results show that parasitic gas-phase reactions become significant at higher pressures and temperatures resulting in a decrease in deposition rate. It is seen that the deposition rate becomes a maximum at the O2/DES ratio of around 2.5. A temperature of 475℃, a pressure of 0.75 torr, and a total now rate of 1,000 sccm are found to be desirable for obtaining both high deposition rate and good film uniformity.
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