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Brooks direct liquid injection vaporizer employs hot gas, rather than a hot metal surface, to accomplish liquid vaporization. As liquid enters the hot gas chamber, it is atomized by a carrier gas stream. Once the atomized liquid contacts the hot gas, it immediately changes to vapor. The result is chemically pure vapor, free of decomposition byproducts or liquid carry-over. Moreover, a Brooks direct liquid injection vaporizer can accept multiple liquid inlets and will generate perfectly mixed vapors. Brooks offers several heat exchanger designs to accommodate an extraordinarily wide range of liquid properties: extremely low vapor pressures (sub 1 torr), very low flow rates (sub 5 grams per hour), and very high flow rates (more than 15 kg/hr). Unlike bubblers and hotsurface vaporizers, Brooks direct liquid injection vaporizers are extremely efficient at producing vapor from liquid.
The Brooks direct liquid injection vaporizer is close to being a true "vapor-on-demand" system because increasing, decreasing, or stopping the incompressible liquid flow quickly results in the desired change in vapor flow. Figure 2 demonstrates the Brooks direct liquid injection vaporizer’s extremely fast response to 900 g/hr tetraethyl orthosilicate (TEOS) step challenges. By comparison, for example, the large bubblers commonly used for MTS (methyltrichlorosilane), BCl3, TiCl4 and similar liquids are difficult to start, run, and stop effectively
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