Abstract: A valve particularly for use within a chemical-mechanical polishing (CMP) system for controlling the supply of slurry and de-ionized water streams while allowing for the constant recirculation of those streams. The valve includes a body having a bore with first and second inlet and outlet port openings for the slurry and water streams, and a third outlet port opening selectably couplable with the first and second inlet ports. A spool or other valve element is slidably received within the bore for axial movement therein, and is positionable within the bore in a null orientation closing the third outlet port to the first and second inlet ports. The spool is movable from the null orientation to a first operating orientation opening the third outlet port path to the first inlet port, and to a second operating orientation opening the third outlet port to the second inlet port.

Abstract: A valve particularly for use within a chemical-mechanical polishing (CMP) system for controlling the supply of slurry and de-ionized water streams while allowing for the constant recirculation of those streams. The valve includes a body having a bore with first and second inlet and outlet port openings for the slurry and water streams, and a third outlet port opening selectably couplable with the first and second inlet ports. A spool or other valve element is slidably received within the bore for axial movement therein, and is positionable within the bore in a null orientation closing the third outlet port to the first and second inlet ports. The spool is movable from the null orientation to a first operating orientation opening the third outlet port path to the first inlet port, and to a second operating orientation opening the third outlet port to the second inlet port.