Abstract: Supply system include a first vessel containing the precursor, a second vessel, a first gas conduit fluidically connecting the first vessel to the second vessel, wherein a pressure reduction device and a flow control device are fluidically mounted therein, a second gas conduit fluidically connecting the second vessel to a point of use, and a pressure gauge downstream the pressure reduction device for measuring a partial pressure of the precursor in the second vessel, wherein the partial pressure of the precursor in the second vessel is at a pressure lower than the saturated vapor pressure of the precursor at the temperature of the second vessel and higher than an inlet pressure requirement of the flow control device at the point of use. Methods for using the supply system are also disclosed.

Abstract: A preprocessing method comprises a sintering step of heating a solid material container filled with a solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and crystallizing at least part of the solid material, and an impurity removal step of heating the solid material container filled with the solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and removing at least part of the impurities included in the solid material.

Abstract: A solid material container for supplying solid materials housed inside by evaporating the solid materials, and includes a carrier gas introduction line, a first filling section that is filled with the solid material, a second filling section that is located in at least a part of an outer periphery of the first filling section, and is filled with the solid material, at least one tray-shaped third filling section that is disposed on the ceiling side of an interior of the solid material container, and a solid material lead-out line.

Abstract: A preprocessing method comprises a sintering step of heating a solid material container filled with a solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and crystallizing at least part of the solid material, and an impurity removal step of heating the solid material container filled with the solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and removing at least part of the impurities included in the solid material.

Abstract: A solid material container for supplying solid materials housed inside by evaporating the solid materials, and includes a carrier gas introduction line, a first filling section that is filled with the solid material, a second filling section that is located in at least a part of an outer periphery of the first filling section, and is filled with the solid material, at least one tray-shaped third filling section that is disposed on the ceiling side of an interior of the solid material container, and a solid material lead-out line.

Abstract: A method for producing a highly pure PMDA comprises at least the following steps: (1) a step of preparing a raw material solution by dissolving a raw material of a pyromellitic dianhydride in an acetic acid solvent, (2) a step of preparing a precursor pyromellitic dianhydride by recrystallizing the pyromellitic dianhydride in the prepared raw material solution and separating the acetic acid solvent, (3) a step of performing a degassing treatment on the precursor pyromellitic dianhydride by stirring the precursor pyromellitic dianhydride in a fluidized state while heating under reduced-pressure conditions, and (4) a step of taking out the pyromellitic dianhydride subjected to the degassing treatment.

Abstract: Disclosed is a film formation method, including vaporizing a plurality of raw material monomers in respective corresponding vaporizers, supplying the plurality of raw material monomers into a film formation apparatus, causing vapor deposition polymerization of the plurality of raw material monomers in the film formation apparatus to form an organic film on a substrate, and removing an impurity contained in at least one raw material monomer among the plurality of raw material monomers before the vapor deposition polymerization.

Abstract: A method for producing a highly pure PMDA comprises at least the following steps: (1) a step of preparing a raw material solution by dissolving a raw material of a pyromellitic dianhydride in an acetic acid solvent, (2) a step of preparing a precursor pyromellitic dianhydride by recrystallizing the pyromellitic dianhydride in the prepared raw material solution and separating the acetic acid solvent, (3) a step of performing a degassing treatment on the precursor pyromellitic dianhydride by stirring the precursor pyromellitic dianhydride in a fluidized state while heating under reduced-pressure conditions, and (4) a step of taking out the pyromellitic dianhydride subjected to the degassing treatment.

Abstract: Disclosed is a film formation method, including vaporizing a plurality of raw material monomers in respective corresponding vaporizers, supplying the plurality of raw material monomers into a film formation apparatus, causing vapor deposition polymerization of the plurality of raw material monomers in the film formation apparatus to form an organic film on a substrate, and removing an impurity contained in at least one raw material monomer among the plurality of raw material monomers before the vapor deposition polymerization.

Abstract: Methods for cleaning a stannane distributions system. A stannane distribution system connecting a stannane supply source and a semiconductor manufacturing tool is provided. Stannane is flown through the system, and a tin layer is formed on the components of the distribution system. This tin layer is then cleaned from the distribution system without the use of liquid cleaning chemicals.

Abstract: To provide a stannane gas supply system capable of supplying a stannane gas to an extreme ultraviolet ray radiation source with a stable flow rate. A stannane gas supply system for supplying a stannane gas to an extreme ultraviolet ray radiation source characterized by comprising a sealed container for storing a mixture of a stannane liquid and a stannane gas, connected with the extreme ultraviolet ray radiation source via a pipe, cooling means for cooling the sealed container to a temperature lower than ?60° C., a low pressure mass flow controller provided in the pipe, a pressure detecting device mounted in the pipe part disposed between the sealed container and the low pressure mass flow controller, for detecting the pressure of the stannane gas in the pipe part, and controlling means for controlling the cooling degree of the sealed container by the cooling means based on the pressure detection value by the pressure detecting device.

Abstract: Provided is a process of preparing a slurry sample containing abrasive particles useful in CMP for observation with a scanning electron microscope in order to monitor particle size distribution. The process comprises providing a slurry sample containing abrasive particles useful in CMP, and placing a sample of the slurry on an iso-pore filter to thereby remove liquid from the slurry.

Abstract: Provided is a method for preparing a fluid containing size-controlled particles that is optimized with respect to use of a target fluid as a matrix fluid under conditions approximating actual conditions. In a preferred embodiment, size-controlled SiO2 particles are obtained by mixing and dispersing SiO2 starting particles having various sizes in a N2 carrier gas followed by fractionation with a fractionator. The size-controlled particles are electrostatically collected by a porous member from the carrier gas flow. Ultrasonic vibrations are then applied to the porous member while a HCl matrix fluid flows through the porous member loaded with the size-controlled particles. This causes release of the size-controlled particles from the porous member and their admixture and dispersion into the HCl matrix fluid.

Abstract: Provided is a safe method for qualifying the cylinder valves on gas cylinders, which method can also clean the cylinder valve when necessary. Compressed gas residing in a gas cylinder is discharged through the flow path of a cylinder valve with the cylinder valve on the gas cylinder in an open position. During this process ultrasound vibrations from the generator are applied to the cylinder valve and the number of particles in the outflowing gas is counted by a detector. The cleanliness of the cylinder valve is evaluated based on the detected value of the number of particles provided by the detector. When the detected value exceeds a standard value, the application of ultrasound vibrations, counting of the number of particles, and evaluation of the cleanliness are repeated until the detected value reaches or falls below the standard value.

Abstract: A process to detect metal impurities in a gas or gas mixture including the steps of directing the gas or gas mixture through non-metallic pipings to a sampling device and sampling the gas or gas mixture for metal impurities detection, wherein the sampling device is close to an inlet and/or outlet of a machine employing the gas or gas mixture as a processing gas, the machine being surrounded by a booth containing a gaseous atmosphere which is continuously circulated in the booth, partially renewing said atmosphere continuously, and exhausting excess atmosphere.

Abstract: A process for reducing corrosion in a gas distribution network of ultra high purity gas or any part of said distribution network, including:(a) Wet cleaning the gas distribution network or at least one part thereof with a wet cleaning agent,(b) Liquid drying the gas distribution network or the at least one part thereof with an H.sub.2 O desorbing liquid drying agent selected from the group consisting of acetone dimethylacetal DMP, 2.2 dichloropropane DCP or 2.2 dibromopropane DBP, mixtures thereof and any equivalent thereof,(c) purging said gas distribution network or any part thereof with a dry high purity gas comprising less than 1 ppm of any impurity, and(d) evacuating the gas distribution network or any part thereof at a pressure which is lower than 5.times.10.sup.4 Pascal(e) exposing the gas distribution network or any part thereof to an atmosphere including an ultra high purity corrosive gas or air.

Abstract: A nuclear fuel conversion system comprises a unit for heating and denitrifying a nitric acid solution of uranyl nitrate, plutonium nitrate, or mixture thereof, a unit for grinding denitrified products, a unit connected to the grinding unit through a first conveying unit for roasting and reducing ground products, a unit connected to the roast-reduction unit through a second conveying unit for further grinding and then sieving the roasted and reduced products, and a unit for disposing of waste gases and waste liquor. The denitrification unit includes a microwave generator for heating and denitrifying the nitric acid solution and for cooling the denitrified product, and the first and second conveying units comprise pneumatic carrier means each of which consists of a suction nozzle, cyclone connected to the nozzle through a pipe, and a blower for creating a reduced pressure condition in the pipe.