Abstract: 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.

Abstract: An air filter, a method for manufacturing the same, and also a high efficiency air cleaning apparatus employing the same are disclosed. The air filter includes a supporter and an inorganic material layer that is formed by fixing the powder of the fraipontite mineral to the surface of the supporter, using the powder of an inorganic substance as a binder. The method for manufacturing the filter includes the steps of immersing a supporter in a suspension in which the powder of the fraipontite mineral and the powder of an inorganic substance as a binder are dispersed as the suspensoid, and drying the supporter impregnated with the suspensoid, thereby forming an inorganic material layer fixed to the surface of the supporter. The fraipontite mineral adsorbs and removes gaseous acid or basic impurities in the air while the inorganic substance as a component of the inorganic material layer works as an adsorbent against gaseous organic impurities contained in the space of the air cleaning apparatus.

Abstract: An air cleaning apparatus such as a clean room or the like having an air circulation mechanism which circulates the humidity controlled air through a predetermined air circulation path, wherein the air circulation path is provided with a filter which has a hydrophobic zeolite layer formed on its base filter media surface and another filter which is disposed downstream from the filter having a hydrophobic zeolite layer and is used for removing particulate impurities contained in the circulating air. According to this air cleaning apparatus, gaseous organic impurities and particulate impurities contained in the air circulating in the air cleaning apparatus can be removed without lowering the humidity of the circulating air. Furthermore, since this air cleaning apparatus includes no activated charcoal which is inflammable, the apparatus is excellent from the standpoint of disaster prevention.

Abstract: 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.

Abstract: 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.

Abstract: An apparatus for removing static electricity from charged articles existing in a clean space, particularly in a clean room for the production of semiconductor articles, includes a AC ionizer having a plurality of needle-like emitters disposed in a flow of clean air. A discharge end of each emitter is coated with a dielectric ceramic material. Opposite conductors are also included which are respectively positioned apart from the discharge end of each emitter by a predetermined distance. Each opposite conductor is grounded. Emitters of some of the discharge pairs are connected to a high voltage AC source having added thereto negative voltage bias to thereby form pseudo negative pole emitters, and emitters of the other discharge pairs are connected to a high voltage AC source having added thereto a more positive voltage bias relative to the negative voltage bias to thereby form pseudo positive pole emitters.

Abstract: An apparatus for removing static electricity from charged articles existing in a clean space, particularly in a clean room for the production of semiconductor devices, includes an AC ionizer having a plurality of needle-like emitters disposed in a flow of clean air. A discharge end of each emitter is coated with a dielectric ceramic material. Opposite conductors are also included which are respectively positiond apart from each emitter by a predetermined distance. A DC voltage (or voltages) is applied to the opposite conductors. By adjusting the DC voltage (or voltages), the positive and negative ion concentration generated by each emitter is controlled. Further, a bias voltage may be added to the DC to increase the ion concentration.