Metallic Contamination Contained With In Situ Furnace Processes

A new cleaning system for production furnaces using an electric field protection against ionic contaminants was presented by researchers from Texas Instruments GmbH (Freising, Germany) in the March Journal of the Electrochemical Society . The system was tested for high- and low-temperature processes, and it was shown that the technique could maintain metallic contamination on the same level as standard cleaning with chlorine or HCl. Because the electric field is always active during the process, the cleaning is continuous with no special process time. The in situ cleaning system was shown to reduce the contamination to an acceptable level even in worst-case scenarios. The cleaning processes were tested and the results compared to standard chlorine-based processes. They indicate that the in situ cleaning can replace the conventional process, improve systems utilization, and eliminate environment, safety and health hazards. The system was tested in annealing processes as well as in thermal oxidation. Exceptional results were obtained for mobile ions cleaning at the oxidation furnace at process temperatures as low as 850°C.

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