Patent ID: 6579371
Filing Date: 2003-06-17
Classification: G03F

Abstract:
A system for applying a layer of a flowable material to a substrate, the system comprising:a rotatable chuck for receiving the substrate, a dispensing unit for dispensing an amount of the flowable material onto the substrate, the rotatable chuck further for rotating the substrate and thereby spreading the flowable material across the substrate and conveying a surplus amount of the flowable material away from the substrate, an exhaust system for receiving the surplus amount of the flowable material, a vacuum source for creating an exhaust stream within the exhaust system, the exhaust stream for entraining at least a portion of the surplus amount of the flowable material conveyed away from the substrate and received by the exhaust system, and a vane anemometer disposed within and extending substantially completely across a cross sectional area of the exhaust system, for creating a pressure drop in the exhaust stream across the vane anemometer within the exhaust system and thereby for reducing blow back of the entrained portion of the surplus amount of the flowable material from a downstream position in the exhaust system to the substrate.