Takasago Thermal Engineering Co., Ltd.

Hideto Takahashi

Soichiro Sakata

Katsumi Sato

Takao Okada

The present invention relates to an air filter having an inorganic material layer in which the following adsorbent is fixed on the surface of the supporter using powder of an inorganic substance as a binder. That is, the adsorbent is prepared by impregnating a salt of an inorganic acid to powder of an inorganic substance consisting of at least one of diatom earth, silica, alumina, a mixture of silica and alumina, aluminum silicate, activated alumina, porous glass, activated clay, activated bentonite, or synthetic zeolite. The air filter according to the present invention can adsorb and remove both of gaseous basic impurities and gaseous organic impurities, thus making a very effective filter for manufacturing semiconductor and LCD.

Air cleaning filter, process for preparing the same, and high-level cleaner

Air-cleaning filter, method of producing the same, and high-level

Air cleaning apparatus, air filter and method for manufacturing the same

Apparatus and a method for evaluating the contamination over the surface of a substrate for use in manufacturing semiconductor devices, liquid crystal devices and so on, said contamination being caused by contaminants, for instance airborne organic substances or the equivalent in the clean room atmosphere. For evaluation, there is measured with passage of time in the atmosphere having a substantially constant relative humidity the surface resistivity (R) of the substrate 104 by bringing electrodes 106 into close contact with an insulating film as formed on said substrate surface, or a contact angle (.alpha.) of a liquid-drop 207 dropped on the substrate 206. From this measurement, the degree of said contamination is judged by comparing the value of the surface resistivity or contact angle as measured immediately after rinsing the substrate, with the values of the same as measured after exposing the substrate to the objective atmosphere to be evaluated.

Apparatus and method for evaluating contamination caused by organic

A storehouse is constituted including a clean room 12 and a storage space 10 for storing clean materials, which is isolated from the clean room. The clean air for storage is generated by a storage air generator 36 and is supplied to the storage space 10 through air supply systems 32, 46. The clean air for storage is purified to such a cleanliness level that it contains hydrocarbon group including methane of less than 10 ppb by using the method of combustion with a catalyst, or purified to such a cleanliness level extent that the contact angle of a pure water droplet or the surface resistivity to the clean material surface can be kept at substantially the same level as that which is indicated immediately after cleaning the material, by using a catalytic reaction tower, an activated charcoal filter, or a fluid bed type adsorbing tower, all of which are made by using materials generating no gaseous impurities. Accordingly, it is possible to effectively prevent the substrate surface from contamination caused by the organic substance. No inert gas is employed, thus ensuring safety operation with an inexpensive running cost.

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Kanagawa-ken, Japan

Hideto Takahashi