US3880681A - Method for the transfer of a gas of high purity - Google Patents

Method for the transfer of a gas of high purity Download PDF

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Publication number
US3880681A
US3880681A US256765A US25676572A US3880681A US 3880681 A US3880681 A US 3880681A US 256765 A US256765 A US 256765A US 25676572 A US25676572 A US 25676572A US 3880681 A US3880681 A US 3880681A
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United States
Prior art keywords
gas
valves
tubing
distributing
pure
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Expired - Lifetime
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US256765A
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English (en)
Inventor
Gaston Sifre
Rene Barandon
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Cegelec SA
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Cegelec SA
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C7/00—Methods or apparatus for discharging liquefied, solidified, or compressed gases from pressure vessels, not covered by another subclass
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2203/00—Vessel construction, in particular walls or details thereof
    • F17C2203/06—Materials for walls or layers thereof; Properties or structures of walls or their materials
    • F17C2203/0634—Materials for walls or layers thereof
    • F17C2203/0636—Metals
    • F17C2203/0639—Steels
    • F17C2203/0643—Stainless steels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2203/00—Vessel construction, in particular walls or details thereof
    • F17C2203/06—Materials for walls or layers thereof; Properties or structures of walls or their materials
    • F17C2203/0634—Materials for walls or layers thereof
    • F17C2203/0658—Synthetics
    • F17C2203/066—Plastics
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2205/00—Vessel construction, in particular mounting arrangements, attachments or identifications means
    • F17C2205/03—Fluid connections, filters, valves, closure means or other attachments
    • F17C2205/0302—Fittings, valves, filters, or components in connection with the gas storage device
    • F17C2205/0323—Valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2205/00—Vessel construction, in particular mounting arrangements, attachments or identifications means
    • F17C2205/03—Fluid connections, filters, valves, closure means or other attachments
    • F17C2205/0302—Fittings, valves, filters, or components in connection with the gas storage device
    • F17C2205/0338—Pressure regulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2205/00—Vessel construction, in particular mounting arrangements, attachments or identifications means
    • F17C2205/03—Fluid connections, filters, valves, closure means or other attachments
    • F17C2205/0302—Fittings, valves, filters, or components in connection with the gas storage device
    • F17C2205/0352—Pipes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
    • F17C2227/04—Methods for emptying or filling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2270/00—Applications
    • F17C2270/05—Applications for industrial use
    • F17C2270/0518—Semiconductors
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S148/00—Metal treatment
    • Y10S148/007—Autodoping
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S148/00—Metal treatment
    • Y10S148/051—Etching
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S438/00—Semiconductor device manufacturing: process
    • Y10S438/905—Cleaning of reaction chamber
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S438/00—Semiconductor device manufacturing: process
    • Y10S438/935—Gas flow control
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/0318—Processes
    • Y10T137/0402—Cleaning, repairing, or assembling
    • Y10T137/0441—Repairing, securing, replacing, or servicing pipe joint, valve, or tank
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/0318—Processes
    • Y10T137/0402—Cleaning, repairing, or assembling
    • Y10T137/0441—Repairing, securing, replacing, or servicing pipe joint, valve, or tank
    • Y10T137/048—With content loading or unloading [e.g., dispensing, discharge assistant, etc.]

Definitions

  • ABSTRACT Method for transferring very pure ultimate use gas from a cylinder to a user apparatus through a tube fitted with valves and other distributing and control elements, the tube being fitted, more particularly stated, for regulating flow and pressure.
  • the tubing, valves and other elements are subjected, before the transferring, and before assembly as a flow line, to chemical etching by aqueous solutions of volatile noncontaminating acids, then to decontamination by extensive sweeping by a very pure hot gas to volatilize the acids.
  • the ultimate use gas is subsequently transferred, after assembly and additional sweeping by a pure hot gas, through the decontaminated tubing, valves and other elements, to the ultimate user apparatus, as for example in the transferring of dopantcontaining gas in the manufacturing of semiconductors by epitaxy or diffusion.
  • the present invention concerns a method and a device for transferring very pure gas from a supply to a user apparatus through a pipe fitted with valves and other distributing and control elements, more particularly for regulating flow and pressure. It applies more particularly to the transferring of gas intended for providing the depositing of doping impurities at a predetermined low percentage on pellets made of a basic semiconductor material, for example, silicon, germanium, gallium arsenide, silicon carbide. etc., with a view to manufacturing semiconductors, in installations for treating by epitaxy or by diffusion. or else for any other operation for the treatment of semiconductors requiring the presence of very pure gas. It is also suitable for other applications, such as the transferring of carrier gas for analysis by chromatography or the trans ferring of gas for medical uses.
  • the very pure gases supplied in industry are generally stored either in a cylinder under very high pressure, or sometimes. in the liquid state in a heat-proof container. Their impurity content is in the order of l volume per million (10*). After possible vaporization and expansion, they are often subjected to additional purifying in a purifying apparatus, for example, in the case of hydrogen, to a treatment by selective diffusion through a palladium or palladium alloy membrane. which further reduces their impurity contents.
  • the aim of the present invention is to overcome the above disadvantages. and to provide a method and a device for transferring very pure gas which ensure the maintaining of that purity up to the using apparatus,
  • the method according to the invention is characterized in that the tubing, valves and other distributing and control elements, are subjected, prior to the transferring of gas. to chemical etching by means of acids which are not liable to introduce harmful impurities into the gas, then to a decontamination treatment by extensive sweeping by means of a very pure gas.
  • chemical etching is effected by means of acids free from doping impurities, preferably by means of a mixture of nitric. hydrochloric and hydrofluoric acids having electronic purity.
  • Each tubing element, each valve and each other element. are subjected, after etching, to extensive sweeping by means of a very pure hot gas; the elements are assembled in a place sheltered from impurities; then 'the assembly is subjected to sweeping by means of a very pure gas.
  • the device according to the invention is characterized in that the valves it comprises are manually or pneumatically operated. and in that the tubing, the valves and the other distributing and control elements have their internal surfaces made of stainless steel, metal or alloy, silica glass, polymonochlorotrifluorethylene, or any other polymer having analogous mechanical strength, chemical inertia characteristics and favorable characteristics under vacuum conditions, are etched by means of acids free from impurities liable to be drawn in with the gas to be transferred, subjected to a decontamination treatment by extensive sweeping by means of a very pure hot gas. then assembled. after the fluid-tight sealing, under vacuum conditions. of each component has been ascertained. 1n the case of the use of stainless steel tubing or valves, there are preferably made of steel containing approximately 18 percent chromium and 12 percent nickel.
  • FIGURE shows a schematic representation of an embodiment of gas supply connection tubing and use apparatus according to the present invention.
  • the elements of the gas transferring device from a gas supplying source 1 to a gas use apparatus 2 include tubing 4, connections 5, valves 3, flowmeters 6 which comprise, for example at least on their internal surface, stainless steel containing approximately 18 percent chromium and 12 percent nickel, such as that corresponding to AFNOR standard Z3 CND 18-12 or to designation 316L of US standard AlSl, are subjected, after removal of grease with a hot chlorated solvent such as trichlorethylene, to chemical etching in a bath at 60C having a volumetric composition of about 16 percent nitric acid at adensity of 1.42, 3 percent hydrochloric acid at a density of 1.189, 4 percent by volume of hydrofluoric acid at a density of 1.18 and 77 percent de-ionized water, for several minutes.
  • a hot chlorated solvent such as trichlorethylene
  • the various elements are then stored in filtered air and assembled. after the fluid-tight sealing of each of them under vacuum conditions has been ascertained. After the fluid-tight sealing of the assembly under vacuum conditions has been ascertained. the latter is subjected to a decontamination treatment by sweeping by means of a very pure gas. for example. hydrogen containing not more than 0.1 volume per million of oxygen and dampness. during several days.
  • a very pure gas for example. hydrogen containing not more than 0.1 volume per million of oxygen and dampness. during several days.
  • valves and other distributing and control elements so formed by extensively sweeping them with a very pure sweeping gas :
  • valves and other distributing and control elements are further decontaminated after assembly but prior to the passage of said very pure use gas therethrough by sweeping with another very pure sweeping gas.
  • said another very pure sweeping gas is hydrogen containing not more than about 0.l volume per million of oxygen and water vapor. and further wherein said very pure sweeping gas is nitrogen.
  • said volatile acid is selected from the group consisting of nitric acid, hydrochloric acid and hydrofluoric acid.
  • valves and other distributing and control elements are washed. rinsed and dried after chemical etching and prior to sweeping with decontaminating gas.
  • valves and other distributing and control elements are passivated by immersion in a cold nitric acid bath after washing. rinsing and drying and prior to sweeping with decontaminating gas.
  • a use gas consisting essentially of a very pure carrier gas charged with a doping quantity of a doping impurity is transferred from a use gas supply to a user apparatus where said doping impurity is deposited on a basic semiconductor material at a predetermined low percentage.
  • said use gas being transferred from said use gas supply to said user apparatus via tubing fitted with valves and other distributing and control elements for regulating the flow and pressure of said use gas.
  • the improvement for maintaining the purity of said very pure use gas comprising chemically etching the tubing. valves and other distributing and control elements prior to assembly together in a bath of an aqueous volatile acid selected from the group consisting of nitric acid.
  • valves and other distributing and control elements by extensively sweeping them with a first very pure decontaminating gas; assembling said tubing. valves and other distributing and control elements together". and sweeping said tubing. valves and other distributing and control elements with a second very pure decontaminating gas prior to the transfer of said use gas therethrough.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Drying Of Semiconductors (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
US256765A 1971-05-27 1972-05-25 Method for the transfer of a gas of high purity Expired - Lifetime US3880681A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR717119398A FR2138539B1 (enrdf_load_stackoverflow) 1971-05-27 1971-05-27

Publications (1)

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US3880681A true US3880681A (en) 1975-04-29

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US (1) US3880681A (enrdf_load_stackoverflow)
DE (1) DE2225754A1 (enrdf_load_stackoverflow)
FR (1) FR2138539B1 (enrdf_load_stackoverflow)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4432808A (en) * 1982-05-26 1984-02-21 Textron Inc. Treatment of stainless steel apparatus used in the manufacture, transport or storage of nitrogen oxides
US5759287A (en) * 1993-06-30 1998-06-02 Applied Materials, Inc. Method of purging and passivating a semiconductor processing chamber
US20040188272A1 (en) * 2003-03-25 2004-09-30 Blanks Jeremy Daniel Method for reducing degradation of reactive compounds during transport

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2935429A (en) * 1956-07-25 1960-05-03 Dow Chemical Co Method for cleaning non-drainable tubes
US2948642A (en) * 1959-05-08 1960-08-09 Bell Telephone Labor Inc Surface treatment of silicon devices
US2965523A (en) * 1957-02-12 1960-12-20 Dow Chemical Co Scale removal from ferrous metal surfaces
US3168422A (en) * 1960-05-09 1965-02-02 Merck & Co Inc Process of flushing unwanted residue from a vapor deposition system in which silicon is being deposited
US3461003A (en) * 1964-12-14 1969-08-12 Motorola Inc Method of fabricating a semiconductor structure with an electrically isolated region of semiconductor material
US3511727A (en) * 1967-05-08 1970-05-12 Motorola Inc Vapor phase etching and polishing of semiconductors
US3645812A (en) * 1968-05-03 1972-02-29 Siemens Ag Method of purifying a quartz processing vessel for use in the production of semiconductors

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2935429A (en) * 1956-07-25 1960-05-03 Dow Chemical Co Method for cleaning non-drainable tubes
US2965523A (en) * 1957-02-12 1960-12-20 Dow Chemical Co Scale removal from ferrous metal surfaces
US2948642A (en) * 1959-05-08 1960-08-09 Bell Telephone Labor Inc Surface treatment of silicon devices
US3168422A (en) * 1960-05-09 1965-02-02 Merck & Co Inc Process of flushing unwanted residue from a vapor deposition system in which silicon is being deposited
US3461003A (en) * 1964-12-14 1969-08-12 Motorola Inc Method of fabricating a semiconductor structure with an electrically isolated region of semiconductor material
US3511727A (en) * 1967-05-08 1970-05-12 Motorola Inc Vapor phase etching and polishing of semiconductors
US3645812A (en) * 1968-05-03 1972-02-29 Siemens Ag Method of purifying a quartz processing vessel for use in the production of semiconductors

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4432808A (en) * 1982-05-26 1984-02-21 Textron Inc. Treatment of stainless steel apparatus used in the manufacture, transport or storage of nitrogen oxides
US5759287A (en) * 1993-06-30 1998-06-02 Applied Materials, Inc. Method of purging and passivating a semiconductor processing chamber
US20040188272A1 (en) * 2003-03-25 2004-09-30 Blanks Jeremy Daniel Method for reducing degradation of reactive compounds during transport
WO2004088004A1 (en) * 2003-03-25 2004-10-14 E.I. Dupont De Nemours And Company Method for reducing degradation of reactive compounds during transport

Also Published As

Publication number Publication date
FR2138539A1 (enrdf_load_stackoverflow) 1973-01-05
FR2138539B1 (enrdf_load_stackoverflow) 1973-05-25
DE2225754A1 (de) 1972-12-07

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