Fluid dispensing system having independently operated pumps

• US 6,251,293 B1
• Filed: 02/14/2000
• Issued: 06/26/2001
• Est. Priority Date: 03/28/1989
• Status: Expired due to Fees

• Current Assignee: Entegris Incorporated
• Original Assignee: Millipore Investment Holdings, Ltd. (Merck & Co., Inc.)
• Inventors: Gibson, Gregory M., Snodgrass, Ocie T., Farney, Michael K.
• Primary Examiner(s): Drodge, Joseph W.
• Application Number:
  US09/503,862
• Time in Patent Office: 498 Days
• Field of Search: 210/97, 210/102, 210/134, 210/258, 210/416.1, 210/767, 222/1, 222/189.06, 222/214, 222/252, 222/255, 417/2, 417/53, 417/246, 417/313, 417/383, 417/395, 417/413.1, 417/413.2, 417/413.3, 417/426, 417/540, 417/244, 417/401, 417/402, 417/412, 417/472, 428/593, 501/154
• US Class Current: 210/767
• CPC Class Codes: B01D 29/15 arranged for inward flow filtration
• CPC Class Codes: B01D 29/46 of flat, stacked bodies
• CPC Class Codes: B01D 35/26 Filters with built-in pumps filters provided with a pump mounted in or on the casing aquarium pumps or filters A01K63/04
• CPC Class Codes: F04B 15/02 the fluids being viscous or non-homogeneous
• CPC Class Codes: F04B 43/067 the fluid being actuated directly by a piston
• CPC Class Codes: F04B 7/0076 the members being actuated by electro-magnetic means
• CPC Class Codes: F04B 9/02 the means being mechanical
• CPC Class Codes: F04B 9/1095 having two or more pumping chambers in series
• CPC Class Codes: Y10S 210/90 Ultra pure water, e.g. conductivity water
• CPC Class Codes: Y10T 428/1234 Honeycomb, or with grain orientation or elongated elements in defined angular relationship in respective components [e.g., parallel, inter- secting, etc.]

Abstract

A fluid dispensing system is provided which has a first diaphragm pump, a filter connected to receive the discharge of said first pump, and an accumulator/second diaphragm pump connected to receive the discharge of said filter. Hydraulic fluids pumped by cylinder/piston/stepper assemblies independently actuate each of the diaphragm pumps, providing accurate, controllable and repeatable dispense of the subject fluid. The system further includes a suck-back device downstream of the second pump.

Claims

1. A method of dispensing a fluid for use within the microelectronics industry, including the steps of:

pumping said fluid with first pumping means;

receiving said fluid by operating second pumping means;

dispensing said fluid from an outlet downstream of said second pumping means; and

sucking-back fluid downstream of said second pumping means.

2. The method of claim 1 further comprising filtering said fluid prior to said fluid being received by said second pumping means.

3. The method of claim 1 in which said fluid is one or more of viscous high purity and shear sensitive.

4. A substantially defect-free microelectric substrate, said substrate fabricated by a step of applying a precise volume of fluid thereto, said precise volume pumped by a system comprising first and second pumping means in series and structure operable to suck-back fluid from downstream of said second pumping means.

5. The substrate of claim 4 further comprising filtering said fluid prior to being received by said second pumping means.