Issue



Inventor's Corner -- December


12/01/1999







Air Replenishment Unit

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The air replenishment unit fits in suspended ceiling rails in cleanrooms. An arc-like housing contains a filter, a fan, and a hood muffler to dampen noise. Air moves through intake at the top of the fan and is circulated through the hood and into another filter before it flows into the cleanroom. According to the inventor, the unit is cost-effective and easier-to-handle than other air-replenishment devices that have multiple parts and welded housings that are difficult to mount.

Patent number: 5,961,702

Date granted: October 5, 1999

Inventor: Wolfgang Doneit, Gebhardt Ventilatoren

GmbH & Co.

Waldenburg, Germany

Microscope Stage Assembly

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The microscope stage assembly prevents particles generated by the meshing of gears from scattering onto the hands of an operator. The assembly includes a stage, which has a gear that drives the stage, while another drives the focusing mechanism. Control knobs rotate the gears. A particle collection tray fits between the gears and the control knobs to catch particles falling from the gears. The stage assembly can be outfitted with a vacuum system connected to the stage and focus gears. The vacuum removes particles that are generated from gear meshing. In processes sensitive to particle contamination, such as semiconductor manufacturing, the operator will not carry particles from the microscope when entering the cleanroom.

Patent number: 5,969,857

Date granted: October 19, 1999

Inventor: Chung-woo Byun, Samsung Electronics Co., Ltd.

Suwon, Korea

Portable Cleanroom Cabinet

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The mobile cleanroom cabinet receptacles hold such components as disks or wafers. Air enters through four openings in the unit housing. The two top openings feed the upstream, while the two bottom openings feed the downstream. Collectively, these openings define a recirculating airflow. A blower maintains re-circulation, and a HEPA or ULPA filter near the top openings catches contaminants coming into the cabinet. A charcoal-type filter at the downstream absorbs evaporating fumes and chemicals.

Patent number: 5,944,602

Date granted: August, 31 1999

Inventor: David A. Grundy, TUMI Manufacturing, Inc.
Fremont, CA

Cleanroom Weld

This material can extend the life of pipe welds in gas supply systems. Welds for gas supply pipes normally contain a passivative film and a chromium oxide surface. Iron oxides from the film can cause corrosion and reduce cleanliness, according to the inventor. The invention is a weld that consists of ferritic stainless steel that has an outer surface that contains chromium oxide and no iron oxides.

Patent number: 5,961,158

Date granted: October 5, 1999

Inventor: Tadahiro Ohmi

Japan

Grounding Arrangement

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The arrangement is within the cleanroom floor and is made up of intersecting conductors, which are flexible leads that are jacketed with polyvinylchloride. The leads extend to connecting lines and then to outlets in which cleanroom equipment can be plugged.

Patent number: 5,954,524

Date granted: September 21, 1999

Inventor: Erhard Wingert, Meissner & Wurst GmbH & Co.

Stuttgart, Germany

Plastic Glove Pad

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The invention is a flat, stacked pad of paired, disposable plastic gloves. Each glove has a straight perforated weakened tear line above the wrist portion. Above the tear line is the heat-fused portion of the pad, which has a stapled flap that contains three holes, allowing the glove stack to be mounted. The gloves can be made of many plastic material combinations and used in such applications as cleanroom manufacturing, medicine, and dentistry. The gloves can also be used to handle food and for domestic cleaning purposes.

Patent number: 5,966,741

Date granted: October 19, 1999

Inventor: Miro Klecina

New York, NY

Air Decontamination Method

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Particle-laden air enters the tangential inlet and crosses an axial ionizer. The charged air enters the cyclone vortex, where the electrified particles pass through an axial magnetic field or a centripetal radial electric field. The magnetic field is maintained by conducting turns fed from a rack. The magnetic and/or electric fields enhance the naturally spiraling path of the particles in the cyclone, and channel the particles toward the cyclone. The particles are brought into contact with the cold coil, where condensation occurs and water is injected at the inlet though a nozzle. The particles are then trapped in water, clumped, and ejected together with the water droplets onto the lateral cyclone surface. At the base of the cyclone, the particles and water droplets pass into the tranquilizing chamber through the vents. The particles are then trapped at the water surface, and the level is kept constant by siphon. Purified air is then moved by the deflector back through the cyclone vortex.

Patent number: 5,968,231

Date granted: October 19, 1999

Inventors: Michel Parmentier and Jean-Charles Weber, Grignotage (SARL)
Dombasle, France

Laser Imaging System

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A laser imaging system is used to analyze semiconductor wafer defects that were detected by scanner. The imaging replaces optical microscope review stations. In addition to analyzing defects, the imaging system can be used for microscopic inspections, including defect detection and metrology. The system operates under Class 1 cleanroom conditions, can produce a three-dimensional image that provides quantitative dimensional information, and allows sub-surface viewing of defects lying beneath dielectric layers.

Patent number: 5,963,314
Date granted: October 5, 1999
Inventors: Bruce W. Worster, Dale E. Crane, Hans J. Hansen, Christopher R. Fairley, and Ken K. Lee, of Ultrapointe Corp.

San Jose, CA