Better than Bubblers

Users of bubblers are well aware of their problems including: limited flow rates, film contamination, water filling, and non-uniformity. The RASIRC Steamer has demonstrated improved growth rates and uniformity by elimination of the oxygen carrier gas.

Bubbler versus Steamer Growth Rate

The growth rate of the oxide layer is directly related to the effective diffusion coefficient of the water molecules into the oxide layer and the equilibrium concentration in the immediate area. When a carrier gas is used to deliver water vapor, the carrier gas molecules generate a partial pressure. This partial pressure lowers the partial pressure of water vapor and slows the diffusion of water into the oxide film. The result is lower driving force and slower growth rate.

The RASIRC Steamer compensates for the partial pressure created by the carrier gas by delivery of ultrapure steam at a constant positive pressure. By eliminating the carrier gas and blanketing the entire furnace tube in pure water vapor, even the loading end of the furnace tube reaches maximum theoretical growth rate.

The RASIRC Steamer eliminates contaminants that bubblers pass through to the process. The RASIRC Steamer uses a non-porous hydrophilic membrane that selectively allows water vapor to pass. Selectivity is significant with up to 1,000,000x relative to nitrogen molecules. In the vapor phase, the membrane only allows water. All other molecules are greatly restricted, so contaminants in water such as dissolved gases, ions, TOCs, particles, viruses, bacteria, pyrons, and metals can be removed in the steam phase.

	RASIRC Steamer	Pyrolitic Torch	Catalytic Systems	Bubbler	Direct Liquid Injection
Acquisition Cost
Operating Cost
Scalability
Particulate
Purity
Flow Control
Accuracy
Safety