Clean room air filtering

An air filtering system for filtering an air stream for use in a clean room comprising

• a HEPA (high efficiency particulate air) filter positioned to introduce air into the clean room adjacent to a film deposition system and comprising borosilicate glass, and
• an upstream air filtering bed positioned upstream of said HEPA filter to receive an air stream from adjacent the film deposition system and comprising a basic reagent selected to effectively remove boron contamination from the air stream as said air stream passes through the upstream air filtering bed, said boron contamination being released from borosilicate glass in said HEPA filter.

An air filtering system for filtering an air stream for use in a clean room comprising

• a HEPA (high efficiency particulate air) filter positioned to introduce air into the clean room, and
• an upstream air filtering bed positioned upstream of said HEPA filter to receive from the clean room an air stream containing photoresist compounds and comprising activated carbon impregnated with an antibacterial agent selected to effectively suppress the growth of bacteria on said activated carbon, said bacterial growth resulting from the interaction of photoresist compounds with activated carbon in said upstream air filter.

An air filtering system for filtering an air stream for use in a clean room to effectively remove a process-limiting molecular contaminant therefrom comprising sequentially arranged first and second air filtering beds, said first air filtering bed positioned to receive the air stream from the clean room and comprising a first reagent selected to effectively remove the process-limiting molecular contaminant from the air stream as said air stream passes through the first air filtering bed, and said second air filtering bed positioned to receive the air stream that has passed through said first air filtering bed and comprising a second reagent different from said first reagent.