Issue



Inventor’s Corner


11/01/2005







Removing AMC using water/gas mixtures

This invention is designed to provide a method for removing airborne molecular contaminants (AMC) from internal surfaces of high-purity components and silicon substrates found in advanced semiconductor processes by using purge gases containing oxygen and/or water. In this schematic flow diagram of a test set-up, a double dilution system (A) creates known hydrocarbon concentrations from the contamination gas standard. Nitrogen, XCDA, or other oxygen-containing mixtures are then fed to the carrier input (B). When producing a hydrocarbon mixture to contaminate the surfaces of a test device, nitrogen is used at the carrier input, with the hydrocarbon component concentrations being determined by mass flow controllers (C) and the concentration of hydrocarbons in the gas standard. When the purging performance of the purge gas is being evaluated, either nitrogen or a mixture of nitrogen and oxygen is used at the carrier input, with valve D closed and valves E and F open. A purifier (G) purifies the nitrogen or mixtures. The gas mixtures are then directed to the device under test (H). Hydrocarbon concentrations leaving the device under test are introduced into the input of the gas chromatograph gas analysis system (I), where the hydrocarbon levels can be measured. The faster the hydrocarbon concentration drops in the gas exiting the device under test, the more effective the purging process. A cold trap (J) accumulates condensed hydrocarbons prior to injection into the gas chromatograph (K).
Patent number: 6,913,654
Date granted: July 5, 2005
Inventors: Daniel Alvarez, Jr., and Jeffrey Spiegelman, San Diego, Calif.

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Preparing clean gases for substrates

To prevent contamination of a substrate or a substrate surface-especially in the production of semiconductors and liquid crystals-a gas coming in contact with a base material or substrate is purified by a dust-removing apparatus and an adsorption and/or absorption apparatus so that the concentration of fine particles in the gas is below Class 1,000 [ISO Class 6], and nonmethane hydrocarbon concentration is below 0.2 parts per million. This invention addresses contamination control of wafer manufacturing, of glass substrates in liquid crystal manufacturing, and of substrates in precision machinery manufacturing processes. The drawing shows how the invention is used to clean air to be supplied for creating an air knife in a Class 10,000 [ISO Class 7] cleanroom. Air (A) is treated within the cleanroom by means of a gas-preparing apparatus (B) comprising a dehumidifier (C), and adsorbent (D) for adsorbing gaseous deleterious components that will increase the angle of contact, and a dust-removing filter (E). Air emerging from the apparatus (F) is clean air that is free not only from dust but also from the gaseous deleterious components. It is subsequently supplied to air-knife equipment (G) for cleaning wafers.
Patent number: 6,911,064
Date granted: June 28, 2005
Inventors: Toshiaki Fujii, Tsukuru Suzuki, and Hidetomo Suzuki, Kanagawa-ken, Japan; Kazuhiko Sakamoto, Saitama-ken, Japan.

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Sterilizing drug cartridge assembly

The inventor proposes that many existing drug cartridge manufacturing methods employ sterilization processes that are ineffective or harmful when used on other components. In addition, existing methods often do not efficiently utilize cleanroom environments, thereby adding to manufacturing costs. This invention is designed to be especially advantageous where the drug cartridge device needs to be constructed from multiple components or from more than one type of material, where certain sterilization processes pose problems relating to only a portion of the device, or where it is important that certain steps be carried out in a clean environment. In this close-up view, the drug cartridge assembly includes a liquid container (A) and a nozzle (B). The nozzle also serves as a housing for the liquid container. A cartridge seal (C) may be provided at the end of the cartridge (D) to maintain a drug dose within the cartridge until it is to be ejected from the cartridge assembly. As shown, the cartridge seal may be implemented as a ball-type check valve, including a ball (E) and a sealing member (F). When the ball engages the sealing member, the end of the cartridge is sealed. Typically, a plunger (G) is provided to seal the other end of the cartridge. The end of the nozzle can be fitted with a removable cap (H) during shipping or storage. An injection may be administered by forcing the plunger toward the nozzle opening, applying pressure to the liquid. When the drug cartridge assembly is provided in the ready-to-use configuration shown here, the user does not have to fill the injection device with a measured dose of injectable liquid, as is required with many existing injection devices.
Patent number: 6,883,222
Date granted: April 26, 2005
Inventor: Sergio Landau, Laguna Niguel, Calif.

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