L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des

L'air Liquide

L'air Liquide, Societe Anonyme L'etude Et L'exploitation Des Procedes

Jean-Marie Friedt

Eiichi Ozawa

Juichi Arai

Pierre Claverie

Masao Kimura

Frederic Rotman

Henri Chevrel

Pierre Jalby

A Nimal Liyanage

Hideki Takagi

Kazuo Yokogi

Kohei Tarutani

Masahiko Matsukata

Toshiyuki Tsukamoto

Alain Boireau

Taeko Hattori

Toshinori Kojima

Jeome Perrin

A method of detecting a malfunction or failure of a pressure regulator in a corrosive or reactive gas distribution system while in use involves continuously measuring or monitoring the output pressure of the pressure regulator, both in the presence and the absence of gas flow. The onset of a malfunction of the pressure regulator can be predicted when the differential output pressure between flowing and non-flowing gas fluctuates highly and increases gradually. Failure of the pressure regulator or of the total system is detected when the differential output pressure in the presence and absence of flowing gas exceeds some experimentally determined value.

Method and system for assessing the operating condition of a pressure

A process for reducing corrosion in a gas distribution network of ultra high purity gas or any part of said distribution network, including:

Process for distributing ultra high purity gases with minimized corrosion

A process to avoid or limit corrosion at the junction of two piping comprising devices welded together, said piping comprising devices being adapted to flow corrosive gases through them, said process comprising the steps of:

Process for assembling piping or components by TIG welding

A process for welding stainless steel tubing in the presence of an inert gas comprising a silicon base gas, in particular silane SiH.sub.4. During the welding operation, a suitable quantity of silicon is deposited by chemical vapor deposition at the weld joint to significantly improve the corrosion resistance of the weld.

Corrosion resistant welding of stainless steel

A process for coating powders with ultrafine particles of silicon, silicon oxide, silicon nitride or alloys thereof, entailing:

Process for the elaboration of powders uniformly coated with ultrafine

A process for producing a deposit of an inorganic and amorphous protective coating on an organic polymer substrate, the coating comprising compounds in the form of an oxide, nitride, carbide, or alloys thereof, by photosensitized decomposition in the gas phase, which comprises decomposing a gas medium by photosensitized decomposition, including precursors of the elements constituting the deposit of the inorganic and amorphous protective coating to be produced by photonic excitation of an impurity which has been previously introduced into the medium, said decomposition being adapted for producing an indirect transfer of energy to the molecules of the medium, thereby causing the decomposition and subsequent deposition of the these elements onto the substrate.

Process for producing a deposit of an inorganic and amorphous protective

The invention relates to a method of forming a silicon diffusion and/or overlay coating on the surface of a metallic substrate comprising the steps of introducing the sample into a cold wall Low Pressure Chemical Vapor Deposition (LPCVD) enclosure, evacuating the enclosure up to a pressure P.sub.1 which is lower than 0.5 Torr, maintaining said pressure P.sub.1 while heating up said sample to a temperature which is comprised between about room temperature and about 300.degree. C., bringing under same pressure P1 the sample to the CVD temperature comprised between about 50.degree. C. and 1000.degree. C., introducing a gas or gas mixture comprising at least one silicon hydride gas, maintaining the pressure inside the enclosure between about 0.1 and about 100 Torr, maintaining the introduction of said gas or gas mixture in the enclosure for deposition and/or diffusion of silicon on and/or through the surface of said metallic sample to obtain the desired thickness of the silicon diffusion and/or overlay coating, cooling down the sample to about room temperature and withdrawing said sample from said LPCVD enclosure. The substrate is preferably polished to obtain a mirror finish and then cleaned, either mechanically or chemically, with a solvent, or both.

Method of forming a silicon diffusion and/or overlay coating on the

The present invention provides a method of forming a free standing shape made of a material containing refractory metal, which entails providing a mandrel in a CVD enclosure, injecting a refractory halide gas and a reducing gas in the enclosure, reacting the gases in the enclosure to generate a material containing refractory metal, growing a layer of the material containing refractory metal on the mandrel and removing the mandrel to obtain the free standing shape, wherein the reducing gases is a silicon hydride gas or a mixture thereof.

Method of forming refractory metal free standing shapes

The invention relates to a process of making a high purity silicide target comprising the steps of providing a substrate in a CVD enclosure, evacuating said enclosure up to a pressure P1 which is at least equal to or smaller than 5.times.10.sup.-5 Torr, heating the substrate at a temperature T1, which is at least equal to or greater than 20.degree. C., injecting in said enclosure a refractory metal halide MXm having a purity, as far as metallic impurities are concerned, greater than 5N (99,999%) and a silicon hydride having a purity, as far as metallic impurities are concerned, greater than 6N (99,9999%) setting the pressure in the enclosure between about 0.01 Torr and the atmospheric pressure while maintaining the temperature in the CVD enclosure between about 20.degree. C., growing a refractory metal silicide layer on the substrate to make a target having a purity, as far as metallic impurities are concerned, greater than 5N (99,99%), maintaining the temperature in the enclosure during said growing step at a value T2 which is not greater than T1, then withdrawing the target from said CVD enclosure.

Growing community of inventors

Tokyo, Japan

Jean-Marie Friedt