Air is drawn into the cleanroom as a gaseous medium by at least one outside air device located downstream from an outer air collection channel. The air device and collection channel form a unit that is situated in an equipment chase or chamber.
From the outer air device, a chemical-adsorptive filter processes air that flows in a region above a plenum. Conduits project air down into the plenum through at least one mechanical filter and into flow chambers that move air to processing units or surfaces.
Clean and processed air travels through flow chambers, through a perforated floor into a collection chamber in which the air is mixed with the processed air. Re-circulated air is drawn through filter-ventilators and filtered again before entering the cleanroom.
Patent number: 6,306,189
Date granted: October 23, 2001
Inventor: Manfred Renz, M+W Zander Facility Engineering GmbH & Co. (Germany)
The method calls for a plastic surface to be immersed in a solution of iso-propanol, or another light alcohol, and potassium hydroxide (KOH).
The method can be used for cleaning and etching plastic surfaces, such as PVC, with heavy organic chemical contamination. For best results, the concentration of KOH should be more than 10 g/l. Iso-propanol or another light alcohol is used to dissolve the KOH, and a plastic part is kept immersed in the solution for about 10 minutes under constant agitation.
After treatment, the surface is rinsed with de-ionized water until the pH of the water drops and the surface of the treated material tests neutral after litmus sampling.
Patent number: 6,303,554 B1
Date granted: October 16, 2001
Inventors: Donato Casati, Fabio Mauri, Silvano Passagrilli, of IBM Corp. (Armonk, NY)
Wafer cleaning system
The apparatus has two opposed brushes for cleaning vertically and can be contained in a tank filled with a process liquid. A controller regulates pressure exerted by brushes on the wafer to compensate for wear and tear. Rim-driving wheels engage the manifold, while a porous jacket hooked to a fluid delivery system, simultaneously rotates and cleans the wafer.
The fluid delivery system separately and independently delivers many cleaning solutions to the brushes, ensuring that freshly mixed agents reach the brushes.
The tank can be filled with a process liquid as well as outfitted with a megasonic transducer to enhance brush and wafer cleaning.
Patent number: 6.308,369 B1
Date granted: October 30, 2001
Inventors: Alejandro Garcia, Brent Krick,
Anthony Nichtawitz, Danile Nordeen; Josh Oen, Kenneth Smith, Vincent Suro, Daniel Wolf, of Silikinetic Technology Inc. (Fremont, CA)
Fabric and production method
The spun-fibered fabric is made up of high- and low-density strips that extend the length of the fabric in an alternating pattern. The strips provide the fabric with a higher percent elongation in the cross direction than in the machine direction. The alternating pattern is achieved by using a screen with numerous air-permeable sections that are separated by impenetrable sections.
The inventor says the object of the invention is to manufacture a non-woven fabric having a filament density pattern yielding low tensile strength and high percent elongation in a first direction, while ensuring high tensile strength and low elongation in the opposite direction.
Patent number 6,319,455 B1
Date granted:November 20, 2001
Inventors:Michael Kauschke and Mordechai Turi, of First Quality Nonwovens Inc. (State College, PA)
The clean air fan and motor mount assembly is made up of a bifurcated conical air inlet, a blown air deflector, a motor mount, motor mount supports and a motor and fan.
The conical air inlet and deflector has a long outer wall and a short inner wall that allows the fan motor to be suspended by mounts and supports that are fastened between the outer wall and deflector within the inlet. The fan has a series of vanes that extend outwardly from the longitudinal axis of the fan.
The fan assembly can be used in fan filter units, workstations, cleanroom ceiling systems, sterile suites and in modular or mobile softwall environments.
Patent number: 6,315,525 B1
Date granted: November 13, 2001
Inventor: Terrence Webb, Microzone Corp.
The invention is a cleaning system that includes a sealing container with a stack of saturated, nowoven, fine spunbond fiber wipers.The sheets have an average fiber diameter of less than 18 micrometers, a tensile strength of about 140-g/g/m2. The wipers, soaked in a one percent solution of sodium dioctyl sulfosuccinate, are singly removed from the container and can be applied to a variety of surfaces for cleaning and polishing.
Patent number: 6,315,114 B1
Date granted: November 13, 2001
Inventors: Laura Elizabeth Keck, Nicole Michele Amsler, Andrew Edward Diamond, James J. Holley, of Kimberly-Clark Worldwide Inc. (Neenah, WI)
Send your inventions
Information on the patents highlighted above was obtained through the U.S. Patent and Trademark Office. Inventors who have been granted patents within the last six months for new cleanroom and contamination technology are encouraged to submit them to CleanRooms magazine for publication. Send a brief description of the invention along with a detailed drawing to Mark A. DeSorbo, associate editor, CleanRooms, 98 Spit Brook Road, Nashua, NH 03062, or e-mail at [email protected].