Flow Rate in an LCVD System

Another important factor to be considered in conjunction with the flow rate of monomer is that LCVD occurs predominantly in the glow region. Therefore, the true reaction volume is close to the volume of glow, Fg. However, the volume of glow is not always the same as the volume of the reactor, V, and in certain cases 

Although the sweeping rate of flow does not apply to a gas flow, as mentioned earlier, if such a parameter is compared (e.g., for a rough comparison of resident time of monomer in the reactor), the flow rate in the context of the flow velocity in a 

The linear velocity of gas flow in a vacuum is also dependent on the cross-sectional area of the reactor in which the flow takes place. Therefore, a parameter describing the linear velocity of a flow is given by FjA p, where A is the cross-sectional area (square centimeters). The value of FjA p for a flow of 50 seem in a bell jar of 50-cm diameter at 1 torr is 19.4cm/min, whereas the value of FjA p for a flow of 5 seem in a tube of 5-cm diameter at 0.1 torr is 1940cm/min. 

The parameter that is proportional to the resident time should also be calculated on the basis of FjA p, not F. The parameter VjF or L AjF, where V is the volume of a reactor and L the length of a tube, does not yield a number in units of length because F is equal to d pV)jdt, not dVjdt for a gas flow. 

a comparison of flow rates reveals a difference in monomer feed-in rates only. As is clear from these examples, 50 seem in a bell jar system under the given conditions is actually a much slower flow (in the context of the sweeping rate) than 5 seem in the tube system under the given conditions for the latter case, despite the value of F being 10 times greater. 

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