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This thesis applies a numerical technique, DSMC, to simulate the thermal flow field in a vertical low-pressure Cu-CVD reactor. It is incorporated with a project supported by a manufacturer and the National Science council, ROC, under a contract, NSC87-2622-E-009-004. The main purpose is to provide the simulation data as a reference for designing the reacting chamber. According to the requirement of the manufacturer, the effects of rotating injector with fixed suscepter are investigated numerically in this thesis. The parametric studies are based on the changes in physical conditions, such as reactor pressure, temperature of substrate, inlet flow rate, angular velocity of rotating injector and carrier gas. The effect of distance between the injector and substrate is also studied. In the meantime, the influence of two different chemical reaction models on the surface deposition of substrate is considered as well. The results show that a good deposition uniformity for the angular velocities within the domain of 10 to 20 rpm can be achieved. When the reactor pressure increases, the deposition rate increases but the uniformity becomes worse. Increasing the percentage of reactant in precursor can raise the deposition rate more effectively than increasing the reactor pressure. It can also obtain a better deposition uniformity. A higher deposition rate and a better deposition uniformity can be reached by shorting the distance between the injector and substrate. However, an enough distance should be reserved to let the robot arm be able to deliver the wafer into and out from the reacting chamber. When a carrier gas with lower molecular weight is used, a higher deposition rate but with a worse deposition uniformity is found. The high temperature of substrate results in a high temperature in the injector, therefore, the temperature of suscepter suggested not too high in order not to make the reactant deposition on the its aperture to block the transportation of carrier gas and reactants.
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