Process gas distribution system and method
AssigneeSCI Systems, Inc.
InventorsDennis A. Sierk, Ronald R. DuRoss, Stephen G. Geist, Gregory L. Hayes
Life of this patent
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Abstract
Gas flow control units in cabinet are connected to distribute process gas, on demand, to a plurality of utilization locations known as "tool" locations in a semi-conductor manufacturing plant. The flow control units are adapted to deliver process gas selectively from one of two supply tanks to any one or all of four different tool locations. Simple, fast, low-cost purging of the gas delivery conduits is provided to facilitate maintenance, gas cylinder changes, etc. Means are provided to enable pulse purging of the long gas delivery conduit from the cabinet to the tool when flow-through or other purging is not possible.
Claims16
A process gas distribution control unit, said control unit comprising, in combination, a cabinet, a plurality of distribution conduit legs and an interconnecting conduit between said distribution conduit legs in said cabinet, means for delivering process gas selectively through at least one of said conduit legs to one or more utilization locations, means responsive to computer control for selectively isolating said legs from said interconnecting conduit and from one another, and for purging said legs by a cycle of alternatingly connecting each of said distribution legs first to a vacuum source to evacuate said legs, and then to a purge gas source to fill said legs with a purge gas, said purging of said legs being accomplished while permitting delivery of process gas to one or more utilization locations through said interconnecting conduit and through those legs which are not being purged at the same time, and computer means for controlling and repeating said cycle a pre-determined number of times, in accordance with stored data representing said pre-determined number.
In a process gas distribution control unit for delivering process gas through an elongated conduit to a remote semiconductor fabrication tool, a method for purging said elongated conduit of process gas comprising the steps of:
- closing said elongated conduit at a point adjacent said tool,
- alternatingly applying first a vacuum and then a purge gas source to said elongated conduit from a location in or proximate to said control unit for a pre-determined time duration for each of said applications of vacuum and purge gas, and for a predetermined number of cycles during which said applications are repeated.
A method of purging process gas from selected legs of a multileg distribution manifold for delivering process gas to selected ones of a plurality of different tool locations, said distribution manifold being contained within a cabinet and including an interconnecting conduit connecting said legs, said method comprising the step of
- selectively isolating each of said legs from said interconnecting conduit and from the others of said legs and purging said legs by applying to each in alternating steps of a pre-determined number and time duration a vacuum and a purge gas source while permitting delivery of process gas to one or more utilization locations through said interconnecting conduit and through legs which are not being purged at the same time.
Dependencies are inferred from the claim text.