Abstract: A method of applying a layer of a flowable material to a substrate. The substrate is received with a rotatable chuck, and an amount of the flowable material is dispensed on to the substrate. The substrate is spun on the rotatable chuck, thereby spreading the flowable material across the substrate and conveying a surplus amount of the flowable material away from the substrate. An exhaust stream is created with a vacuum source. At least a portion of the surplus amount of the flowable material conveyed away from the substrate is entrained into the exhaust stream, which exhaust stream is conveyed into an exhaust system. A pressure drop is created in the exhaust stream across a vane anemometer within the exhaust system. The 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 is thereby reduced.

Abstract: A method of applying a layer of material to a substrate. The substrate is received with a chuck, and the material is dispensed. The substrate is spun on the chuck, spreading the material and conveying a surplus of the material away. The surplus of the material conveyed away is entrained into an exhaust stream. A pressure drop is created in the exhaust stream across a vane anemometer. The blow back of the entrained surplus of the material from a downstream position in the exhaust system to the substrate is thereby reduced.

Abstract: A method of applying a layer of a flowable material to a substrate. The substrate is received with a rotatable chuck, and an amount of the flowable material is dispensed on to the substrate. The substrate is spun on the rotatable chuck, thereby spreading the flowable material across the substrate and conveying a surplus amount of the flowable material away from the substrate. An exhaust stream is created with a vacuum source. At least a portion of the surplus amount of the flowable material conveyed away from the substrate is entrained into the exhaust stream, which exhaust stream is conveyed into an exhaust system. A pressure drop is created in the exhaust stream across a vane anemometer within the exhaust system. The 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 is thereby reduced.