Abstract: An industrial material such as metal, ceramics or plastics whose surface has a film passivated by fluoridation and a process of manufacturing the above industrial material. The industrial material comprises a substrate, a nickel alloy film formed on the substrate and containing nickel, semimetal and/or other metal whose fluoride becomes a volatile compound, and a fluorine passivated film formed at least on a surface of the nickel alloy film in such a manner that the fluorine passivated film contains nickel and does not contain said other metal or the semimetal, and satisfies stoichiometric ratio. The process of manufacturing an industrial material comprises the steps of performing grounding treatment of a surface of a substrate, forming a nickel alloy film, on the surface of the substrate, containing nickel, semimetal and/or other metal, and forming a fluorine passivated film on the nickel alloy film.

Abstract: A metal material characterized in that the material comprises a substrate metal, a film comprising a nickel fluoride layer and formed on the substrate metal, and a film comprising a carbon layer and formed on the film.

Abstract: A method of improving the surface of polypropylene product characterized is that the surface of polypropylene product is improved by contacting with diluted fluorine gas of concentration of 0.1-10% for 1-30 minutes to make it hydrophilic with the surface contact angle 80 degrees or less.

Abstract: Hydrofluoric acid has incorporated therein a hydrocarbon nonionic surfactant having an HLB value of 7 to 17. The composition exhibits improved wetting and other properties for use in surface treatment for micro processing.

Abstract: A metal material characterized in that the material comprises a substrate metal, a film comprising a nickel fluoride layer and formed on the substrate metal, and a film comprising a carbon layer and formed on the film.

Abstract: An etching agent and an electronic device manufacturing method using the etching agent. The etching agent contains, in a solution, hydrofluoric acid at a concentration of 0.05 to 0.5 mol/l, and halooxoacid ions, represented by the formula (XO.sub.n).sup.p- (wherein X is a halogen element, n is 3, 4 or 6, p is 1, 2 or 3), at a concentration of at least 0.01 mol/l. An electronic device manufactured using the etching agent requires only a single etching step to etch both conductive layers (such as aluminum) as well as ohmic contact layers (a-Si).

Abstract: A metal material characterized in that the material comprises a substrate metal, a film comprising a nickel fluoride layer and formed on the substrate metal, and a film comprising a carbon layer and formed on the film.

Abstract: Fluorine is recovered as calcium fluoride from a fluoroetchant solution composed mainly of hydrogen fluoride and ammonium fluoride using a sealed reaction tank equipped with a supply port for adding the fluoroetchant solution to the tank, a supply port for adding calcium carbonate to the tank, a vapor supply port for adding steam to heat the solution in the tank, an air supply port for providing air to aerate the contents of the tank, a stirrer for stirring the contents of the tank, an ejector for removing vapors from the tank connected to the tank via a mist separator for separating mist from the vapors being removed from the tank, and an exhaust port for removing calcium fluoride from the tank.

Abstract: Calcium fluoride with high purity of very small content of unreacted calcium carbonate and silica is recovered from an etchant mainly composed of hydrogen fluoride or hydrogen fluoride and ammonium fluoride. The etchant is reacted with calcium carbonate with transfer directions of the etchant and calcium carbonate being controlled within a composition region in which mole equivalent ratio of ammonium fluoride/hydrogen fluoride is specified.

Abstract: A method of preparing hydrofluoric acid of high purity at the point of use by causing molecular diffusion of hydrogen fluoride into ultrapure water through a resin membrane. The high-purity acid is available at the site of use free of contamination that would occur during transport from a site of preparation.

Abstract: Dry etching apparatus composed of any of metal, silica, ceramic or combination thereof with a processing chamber in which substrates are placed and a diluted anhydrous hydrogen fluoride gas generator, the processing chamber being connected to the diluted anhydrous hydrogen fluoride gas generator through a pipe line of stainless steel or nickel. There is also disclosed a dry-etching method with the dry-etching apparatus, and a diluted anhydrous hydrogen gas generator used in the dry-etching apparatus and dry-etching method.

Abstract: Disclosed is a dry-etching apparatus composed of any of metal, silica, ceramic or combination thereof including a processing chamber in which substrates are placed and a diluted anhydrous hydrogen fluoride gas generator, the processing chamber being connected to the diluted anhydrous hydrogen fluoride gas generator through a pipe line of such metal as stainless steel or nickel. There is also provided according to the invention a dry-etching method with the dry-etching apparatus, a cooled anhydrous hydrogen fluoride gas source and a diluted anhydrous hydrogen gas generator used in the dry-etching apparatus and dry-etching method.

Abstract: A metal material characterized in that a film passivated by fluorination which is mainly composed of a metal fluoride substantially satisfying stoichiometric ratio is formed at least partially on a surface of a metal of the metal material, and an apparatus at least partially composed of the metal material.