US2999737A - Production of highly pure single crystal semiconductor rods - Google Patents
Production of highly pure single crystal semiconductor rods Download PDFInfo
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- US2999737A US2999737A US806882A US80688259A US2999737A US 2999737 A US2999737 A US 2999737A US 806882 A US806882 A US 806882A US 80688259 A US80688259 A US 80688259A US 2999737 A US2999737 A US 2999737A
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- 239000004065 semiconductor Substances 0.000 title claims description 41
- 239000013078 crystal Substances 0.000 title claims description 12
- 238000004519 manufacturing process Methods 0.000 title description 2
- 239000000463 material Substances 0.000 claims description 28
- 238000010891 electric arc Methods 0.000 claims description 16
- 150000001875 compounds Chemical class 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 11
- 238000006243 chemical reaction Methods 0.000 claims description 10
- 239000000155 melt Substances 0.000 claims description 7
- 238000010438 heat treatment Methods 0.000 claims description 6
- 238000007598 dipping method Methods 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims description 3
- 238000005979 thermal decomposition reaction Methods 0.000 claims description 3
- 239000012768 molten material Substances 0.000 claims description 2
- 238000002844 melting Methods 0.000 description 12
- 230000008018 melting Effects 0.000 description 12
- 239000007789 gas Substances 0.000 description 8
- 238000000926 separation method Methods 0.000 description 6
- 238000000354 decomposition reaction Methods 0.000 description 4
- 239000012495 reaction gas Substances 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 230000005672 electromagnetic field Effects 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 150000003377 silicon compounds Chemical class 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000004807 localization Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/08—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
- B01J19/087—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electric or magnetic energy
- B01J19/088—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electric or magnetic energy giving rise to electric discharges
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B19/00—Selenium; Tellurium; Compounds thereof
- C01B19/007—Tellurides or selenides of metals
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
- C01B21/064—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with boron
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
- C01B21/072—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with aluminium
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/06—Hydrogen phosphides
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B35/00—Boron; Compounds thereof
- C01B35/02—Boron; Borides
- C01B35/04—Metal borides
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B41/00—Obtaining germanium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B5/00—General methods of reducing to metals
- C22B5/02—Dry methods smelting of sulfides or formation of mattes
- C22B5/16—Dry methods smelting of sulfides or formation of mattes with volatilisation or condensation of the metal being produced
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/007—Preparing arsenides or antimonides, especially of the III-VI-compound type, e.g. aluminium or gallium arsenide
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/003—Coating on a liquid substrate
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B11/00—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method
- C30B11/04—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method adding crystallising materials or reactants forming it in situ to the melt
- C30B11/08—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method adding crystallising materials or reactants forming it in situ to the melt every component of the crystal composition being added during the crystallisation
- C30B11/12—Vaporous components, e.g. vapour-liquid-solid-growth
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
- C30B15/02—Single-crystal growth by pulling from a melt, e.g. Czochralski method adding crystallising materials or reactants forming it in situ to the melt
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/32—Gas-filled discharge tubes
- H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
- H01J37/32018—Glow discharge
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
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- 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
- Y10S117/00—Single-crystal, oriented-crystal, and epitaxy growth processes; non-coating apparatus therefor
- Y10S117/901—Levitation, reduced gravity, microgravity, space
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- 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
- Y10S117/00—Single-crystal, oriented-crystal, and epitaxy growth processes; non-coating apparatus therefor
- Y10S117/917—Magnetic
Definitions
- This invention is concerned with producing highly pure single crystal semiconductor rods, especially silicon rods, by separation of the semiconductor material in a glowarc discharge, comprising dipping into a drop-shaped highly pure semiconductor melt a thin single crystal of the semiconductor material having a cross-sectional area which is small as compared with the surface area of the melt, and thereupon moving the single crystal from the melt, resulting in the drawing of a thin semiconductor rod, the drawing speed being such that substantially as much semiconductor material solidifies at the drawn rod as is newly formed at the surface of the molten zone by thermal decomposition of a. highly pure gaseous compound of the semiconductor material.
- silicon from the gaseous compound will under some circumstances be deposited not only upon the surface of the molten zone but also upon colder parts.
- the molten zone itself forms one electrode of one gas discharge or of a plurality of gas discharges, preferably glow-arc discharges, and the highly pure gaseous compound of the semiconductor material is injected in the direction of the molten zone.
- the gaseous compound of the semiconductor material, subjected to the gas discharge, is decomposed and the semiconductor material to be obtained is precipitated upon the electrodes, that is, when using a direct current discharge according to the invention, upon the one electrode which is formed by the molten zone and connected as cathode.
- the advantage of using a glow-arc discharge which constitutes a special form of the arc discharge is, that the discharge does not impact the cathode as a focal point but distributed over a relatively large area, resulting in a correspondingly large area of the zone of the semiconductor which is thereby brought to melting temperature and, accordingly, in a large-area reaction zone.
- the heat development at the cathode and also the decomposition of the reaction gas are moreover better effective in the high cathode drop of the glow-arc discharge.
- the invention proposes to provide for advantageously uniform heating of the melting zone and uniform separation of the semiconductor material, a plurality of counter electrodes (anodes) disposed circularly distributed about the melting zone and connected with positive potential, resulting in a plurality of parallel effective glow are discharges.
- the gas stream containing the silicon compound is introduced into the reaction vessel so that it is advantageously confined to the immediate neighborhood of the counter electrodes and aimed in the direction of the melting zone. It is particularly advantageous to pro vide tubular counter electrodes and to introduce the raaction gas therethrough.
- FIG. 1 is a longitudinal sectional view of apparatus for practicing the invention
- FIG. 2 is a transverse sectional view of the apparatus assuming the use of five counter electrodes
- FIG. 3 shows in transverse sectional view an embodiment in which a closed ring-shaped member is used as a counter electrode.
- the electrodes serving as anodes in the glow-arc discharge, extend laterally of the melting zone at which is effected the decomposition of the highly pure gaseous compound of the semiconductor material.
- Sealed into the reaction vessel 1 which may, for example, be made of quartz, are the gas discharge conduit 9 and the counter electrodes (anodes), of which two are shown in schematic sectional view and designate-d by numerals 10 and 12.
- Within the vessel is arranged a polycrystalline rod 2 of semiconductor material, at the upper end or" which is formed the melting zone 4 into which is dipped the single crystal seed 5. From this melt at which the continuously introduced gas mixture containing a gaseous semiconductor compound is decomposed, is drawn the thin single crystal rod 3.
- a coil 6 may be arranged in the reaction vessel, producing an electromagnetic field for supporting the melting zone.
- the thin semiconductor rod. 3- may be disposed rotatably and axially movable so as to obtain desirable temperature distribution and continuous adjusted removal of the rod in accordance with the growth thereof.
- FIG. 2 shows a transverse section of the arrangement employing, for example, five counter electrodes 10, 12, 15, 18 and 19 sealed into the reaction vessel, thus providing for a plurality of parallel effective glow-arc discharges.
- These counter electrodes are arranged circularly about the melting zone in order to obtain uniform heating and uniform separation of the desired semiconductor material. The uniform heating and material separation may be supported for example, by rotation of the melting zone.
- the counter electrodes are advantageously made of copper and may be water-cooled by suitable means not shown) so as to prevent precipitation of semiconductor material thereon.
- the counter electrodes are tubular, providing ducts 1'1, 13, 16, 17 and 20' for directing the reaction gas to the melting zone so as to favor separation thereat.
- FIG. 3 shows a further embodiment in which the counter electrode is formed by a closed ring-shaped member 21 which faces the melting zone, the single crystal being drawn therethrough.
- a suitable gas inlet must be provided for the reaction vessel.
- the glow discharge is rotated by a magnetic field arranged substantially radially or perpendicularly to the direction of the current thereof. The potential gradient of the glow-arc discharge is thereby increased and the decomposition of silicon compound is favored, that is, the amount of semiconductor material separated in a time unit is increased.
- doping substances may be added to the gaseous semiconductor compound so as to perm-it drawing of a single crystal of defined conductivity type or, by intermittent addition of doping substance to the reaction gas, drawing of a semiconductor rod with desired pn-junctions.
- the method of continuously growing in a continuous operation a highly pure relatively thin single crystal rodlike semiconductor body from a melt of said semiconductor material comprising producing within a reaction vessel between one end of a main electrode consisting of said semiconductor material and at least one counter electrode a glow-arc discharge to form said melt at said one end of said main electrode in the form of a substantially drop-shaped molten zone, said electrodes being disposed to produce substantially uniform heating of such molten zone by said glow-arc discharge, dipping into said melt the end of a relatively thin seed member consisting of said semiconductor material and having a cross-sec tional area which is small as compared with the surface area of said drop-shaped melt, directing onto said dropshaped melt a highly pure gaseous compound of said semiconductor material to continuously supply the melt therewith, said gaseous compound decomposing thermal- 1y by the action of said glow-arc discharge to effect continuous deposit of said semiconductor material upon said drop-shaped melt, and continuously withdrawing said body from said drop-shaped melt to cause molten material to solidify thereon at a rate which
- a method according to claim 2. wherein a plurality of glow-arc discharges are eiiected between said cathode formed by said drop-shaped melt and a plurality of counter electrodes arranged about said melt.
- a method according to claim 4, comprising the step of cooling said counter electrodes.
- a method according to claim 1, comprising the step of rota-ting said main electrode carrying said dropshaped melt.
- a method according to claim 1, comprising the step of supporting said drop-shaped melt by an electromagnetic field.
- a method according to claim 1, comprising the step of applying the effect of a magnetic field which is operative radially of the main electrode and perpendicularly of the direction of the glow-arc discharge.
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Description
Sept. 12, 1961 K. SIEBERTZ 2,999,737
PRODUCTION os' HIGHLY PURE SINGLE CRYSTAL SEMICONDUCTOR RODS Filed April 16, 1959 Jwezzfox Jay @5503,
2,999,737 PRODUCTION OF HIGHLY PURE SINGLE CRYSTAL SEMICONDUCTOR RODS Karl Siehertz, Munich, Germany, assignor to Siemens and Halske Alrtiengesellschaft Berlin and Munich, a
corporation of Germany Filed Apr. 16, 1959, Ser. No. 806,882 Claims priority, application Germany Apr. 30, 1958 9 Claims. (Cl. 23-2235) This invention is concerned with producing highly pure single crystal semiconductor rods, especially silicon rods, by separation of the semiconductor material in a glowarc discharge, comprising dipping into a drop-shaped highly pure semiconductor melt a thin single crystal of the semiconductor material having a cross-sectional area which is small as compared with the surface area of the melt, and thereupon moving the single crystal from the melt, resulting in the drawing of a thin semiconductor rod, the drawing speed being such that substantially as much semiconductor material solidifies at the drawn rod as is newly formed at the surface of the molten zone by thermal decomposition of a. highly pure gaseous compound of the semiconductor material.
When the molten zone is inductively heated to the decomposition temperature of the gaseous compound of the semiconductor material which is conducted into the reaction vessel, silicon from the gaseous compound will under some circumstances be deposited not only upon the surface of the molten zone but also upon colder parts.
The method according to the invention avoids this drawback. In accordance with a characteristic feature of the invention, the molten zone itself forms one electrode of one gas discharge or of a plurality of gas discharges, preferably glow-arc discharges, and the highly pure gaseous compound of the semiconductor material is injected in the direction of the molten zone.
The gaseous compound of the semiconductor material, subjected to the gas discharge, is decomposed and the semiconductor material to be obtained is precipitated upon the electrodes, that is, when using a direct current discharge according to the invention, upon the one electrode which is formed by the molten zone and connected as cathode.
The advantage of using a glow-arc discharge which constitutes a special form of the arc discharge is, that the discharge does not impact the cathode as a focal point but distributed over a relatively large area, resulting in a correspondingly large area of the zone of the semiconductor which is thereby brought to melting temperature and, accordingly, in a large-area reaction zone. The heat development at the cathode and also the decomposition of the reaction gas are moreover better effective in the high cathode drop of the glow-arc discharge.
The invention proposes to provide for advantageously uniform heating of the melting zone and uniform separation of the semiconductor material, a plurality of counter electrodes (anodes) disposed circularly distributed about the melting zone and connected with positive potential, resulting in a plurality of parallel effective glow are discharges. In order to favor the separation at the melting zone, the gas stream containing the silicon compound is introduced into the reaction vessel so that it is advantageously confined to the immediate neighborhood of the counter electrodes and aimed in the direction of the melting zone. It is particularly advantageous to pro vide tubular counter electrodes and to introduce the raaction gas therethrough.
The various objects and features of the invention will appear from the description which is rendered below with reference to the accompanying drawing, in which mirgfi rates Patent Q Patented Sept. 12, 3961 FIG. 1 is a longitudinal sectional view of apparatus for practicing the invention;
'FIG. 2 is a transverse sectional view of the apparatus assuming the use of five counter electrodes; and
FIG. 3 shows in transverse sectional view an embodiment in which a closed ring-shaped member is used as a counter electrode.
Referring now to FIG. 1, the electrodes, serving as anodes in the glow-arc discharge, extend laterally of the melting zone at which is effected the decomposition of the highly pure gaseous compound of the semiconductor material. Sealed into the reaction vessel 1 which may, for example, be made of quartz, are the gas discharge conduit 9 and the counter electrodes (anodes), of which two are shown in schematic sectional view and designate-d by numerals 10 and 12. Within the vessel is arranged a polycrystalline rod 2 of semiconductor material, at the upper end or" which is formed the melting zone 4 into which is dipped the single crystal seed 5. From this melt at which the continuously introduced gas mixture containing a gaseous semiconductor compound is decomposed, is drawn the thin single crystal rod 3. A coil 6 may be arranged in the reaction vessel, producing an electromagnetic field for supporting the melting zone. The thin semiconductor rod. 3- may be disposed rotatably and axially movable so as to obtain desirable temperature distribution and continuous adjusted removal of the rod in accordance with the growth thereof.
Smooth, cylindrical semiconductor single crystal rods are in this manner produced which may be drawn from the. reaction vessel by way of the schematically indicated sealing bushing 7. The mounting 14 of the relatively thick semiconductor body 2 is likewise carried to the outside by means of a sealing bushing 8.
'FIG. 2 shows a transverse section of the arrangement employing, for example, five counter electrodes 10, 12, 15, 18 and 19 sealed into the reaction vessel, thus providing for a plurality of parallel effective glow-arc discharges. These counter electrodes are arranged circularly about the melting zone in order to obtain uniform heating and uniform separation of the desired semiconductor material. The uniform heating and material separation may be supported for example, by rotation of the melting zone. The counter electrodes are advantageously made of copper and may be water-cooled by suitable means not shown) so as to prevent precipitation of semiconductor material thereon. In the illustrated example, the counter electrodes are tubular, providing ducts 1'1, 13, 16, 17 and 20' for directing the reaction gas to the melting zone so as to favor separation thereat.
FIG. 3 shows a further embodiment in which the counter electrode is formed by a closed ring-shaped member 21 which faces the melting zone, the single crystal being drawn therethrough. A suitable gas inlet must be provided for the reaction vessel. In order to secure in such case a uniform distribution of the heating and to avoid concentration and localization of the glow-arc discharge, the glow discharge is rotated by a magnetic field arranged substantially radially or perpendicularly to the direction of the current thereof. The potential gradient of the glow-arc discharge is thereby increased and the decomposition of silicon compound is favored, that is, the amount of semiconductor material separated in a time unit is increased.
It is understood, of course, that doping substances may be added to the gaseous semiconductor compound so as to perm-it drawing of a single crystal of defined conductivity type or, by intermittent addition of doping substance to the reaction gas, drawing of a semiconductor rod with desired pn-junctions.
Changes may be made within the scope and spirit of the appended claims which define what. is believed to be new and desired to have protected by Letters Patent.
I claim:
1. The method of continuously growing in a continuous operation a highly pure relatively thin single crystal rodlike semiconductor body from a melt of said semiconductor material, comprising producing within a reaction vessel between one end of a main electrode consisting of said semiconductor material and at least one counter electrode a glow-arc discharge to form said melt at said one end of said main electrode in the form of a substantially drop-shaped molten zone, said electrodes being disposed to produce substantially uniform heating of such molten zone by said glow-arc discharge, dipping into said melt the end of a relatively thin seed member consisting of said semiconductor material and having a cross-sec tional area which is small as compared with the surface area of said drop-shaped melt, directing onto said dropshaped melt a highly pure gaseous compound of said semiconductor material to continuously supply the melt therewith, said gaseous compound decomposing thermal- 1y by the action of said glow-arc discharge to effect continuous deposit of said semiconductor material upon said drop-shaped melt, and continuously withdrawing said body from said drop-shaped melt to cause molten material to solidify thereon at a rate which corresponds substantially to the rate at which said semiconductor material is deposited on said melt by the thermal decomposition of said gaseous compound.
2. A method according to claim 1, wherein the glowarc discharge is a direct current discharge, said dropshaped melt forming the cathode for such discharge.
3. A method according to claim 2., wherein a plurality of glow-arc discharges are eiiected between said cathode formed by said drop-shaped melt and a plurality of counter electrodes arranged about said melt.
4. A method according to claim 3, wherein said counter electrodes are tubular, said gaseous compound of the semiconductor material being supplied through said tubular counter electrodes.
5. A method according to claim 4, comprising the step of cooling said counter electrodes.
6. A method according to claim 1, wherein said glowarc discharge is efiected between said drop-shaped melt and a circular counter electrode disposed about said melt.
7. A method according to claim 1, comprising the step of rota-ting said main electrode carrying said dropshaped melt.
8. A method according to claim 1, comprising the step of supporting said drop-shaped melt by an electromagnetic field.
9. A method according to claim 1, comprising the step of applying the effect of a magnetic field which is operative radially of the main electrode and perpendicularly of the direction of the glow-arc discharge.
References Cited in the file of this patent UNITED STATES PATENTS 2,631,356 Sparks et al. Mar. 17, 1953 2,768,074 Staufier Oct. 23, 1956 2,854,318 Rummel Sept. 30, 1958 2,892,739 Rusler June 30, 1959 FOREIGN PATENTS 1,125,277 France July 9, 1956 OTHER REFERENCES Nelson: Article in Transistors I, RCA Laboratories, pages 66-76, March 1956.
Claims (1)
1. THE METHOD OF CONTINUOUSLY GROWING IN A CONTINUOUS OPERATION A HIGHLY PURE RELATIVELY THIN SINGLE CRYSTAL RODLIKE SEMICONDUCTOR BODY FROM A MELT OF SAID SEMICONDUCTOR MATERIAL, COMPRISING PRODUCING WITHIN A REACTION VESSEL BETWEEN ONE END OF A MAIN ELECTRODE CONSISTING OF SAID SEMICONDUCTOR MATERIAL AND AT LEAST ONE COUNTER ELECTRODE A GLOW-ARC DISCHARGE TO FORM SAID MELT AT SAID ONE END OF SAID MAIN ELECTRODE IN THE FORM OF A SUBSTANTIALLY DROP-SHAPED MOLTEN ZONE, SAID ELECTRODES BEING DISPOSED TO PRODUCE SUBSTANTIALLY UNIFORM HEATING OF SUCH MOLTEN ZONE BY SAID GLOW-ARC DISCHARGE, DIPPING INTO SAID MELT AND END OF A RELATIVELY THIN SEED MEMBER CONSISTING OF SAID SEMICONDUCTOR MATERIAL AND HAVING A CROSS-SECTIONAL AREA WHICH IS SMALL AS COMPARED WITH THE SURFACE AREA OF SAID DROP-SHAPED MELT, DIRECTING ONTO SAID DROPSHAPED MELT A HIGHLY PURE GASEOUS COMPOUND OF SAID SEMICONDUCTOR MATERIAL TO CONTINUOUSLY SUPPLY THE MELT THEREWITH, SAID GASEOUS COMPOUND DECOMPOSING THERMALLY BY THE ACTION OF SAID GLOW-ARC DISCHARGE TO EFFECT CONTINUOUS DEPOSIT OF SAID SEMICONDUCTOR MATERIAL UPON SAID DROP-SHAPED MELT, AND CONTINUOUSLY WITHDRAWING SAID BODY FROM SAID DROP-SHAPED MELT TO CAUSE MOLTEN MATERIAL TO SOLIDIFY THEREON AT A RATE WHICH CORRESPONDS SUBSTANTIALLY TO THE RATE AT WHICH SAID SEMICONDUCTOR MATERIAL IS DEPOSITED ON SAID MELT BY THE THERMAL DECOMPOSITION OF SAID GASEOUS COMPOUND.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DES39578A DE976899C (en) | 1954-06-13 | 1954-06-13 | Gas discharge system for the production of a rod from high-purity silicon |
DES40843A DE1042539B (en) | 1954-06-13 | 1954-09-15 | Process for producing ultra-pure semiconductor crystals |
DES58066A DE1151782B (en) | 1954-06-13 | 1958-04-30 | Process for producing highly purified single-crystalline semiconductor rods |
Publications (1)
Publication Number | Publication Date |
---|---|
US2999737A true US2999737A (en) | 1961-09-12 |
Family
ID=27212571
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US509980A Expired - Lifetime US2992984A (en) | 1954-06-13 | 1955-05-20 | Gas discharge device for producing extremely pure crystalline semiconductor substances |
US806882A Expired - Lifetime US2999737A (en) | 1954-06-13 | 1959-04-16 | Production of highly pure single crystal semiconductor rods |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US509980A Expired - Lifetime US2992984A (en) | 1954-06-13 | 1955-05-20 | Gas discharge device for producing extremely pure crystalline semiconductor substances |
Country Status (6)
Country | Link |
---|---|
US (2) | US2992984A (en) |
CH (3) | CH355220A (en) |
DE (5) | DE1017795B (en) |
FR (3) | FR1131422A (en) |
GB (3) | GB795191A (en) |
NL (1) | NL105537C (en) |
Cited By (12)
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US3129059A (en) * | 1960-04-27 | 1964-04-14 | Wacker Chemie Gmbh | Process for manufacturing high purity gallium arsenide |
US3205046A (en) * | 1959-06-05 | 1965-09-07 | Ind De Pierres Scient Hrand Dj | Rotary arbor for making synthetic stone |
US3224844A (en) * | 1961-03-01 | 1965-12-21 | Philips Corp | Zone-melting method for metal compounds |
US3245761A (en) * | 1962-10-11 | 1966-04-12 | Norton Co | Apparatus for making magnesium oxide crystals |
US3259468A (en) * | 1963-05-02 | 1966-07-05 | Monsanto Co | Slim crystalline rod pullers with centering means |
US3261722A (en) * | 1962-12-12 | 1966-07-19 | Siemens Ag | Process for preparing semiconductor ingots within a depression |
US3293002A (en) * | 1965-10-19 | 1966-12-20 | Siemens Ag | Process for producing tape-shaped semiconductor bodies |
US3351433A (en) * | 1962-12-12 | 1967-11-07 | Siemens Ag | Method of producing monocrystalline semiconductor rods |
US3494742A (en) * | 1968-12-23 | 1970-02-10 | Western Electric Co | Apparatus for float zone melting fusible material |
US3519394A (en) * | 1965-02-10 | 1970-07-07 | Ugine Kuhlmann | Apparatus for the fabrication of a synthetic ruby |
US3634045A (en) * | 1967-04-14 | 1972-01-11 | Atomic Energy Authority Uk | Growing of crystals using electron beam heating and annealize |
US4087313A (en) * | 1975-11-28 | 1978-05-02 | Joseph Beril Milstein | Process and apparatus for preparation of single crystals and textured polycrystals |
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DE1061527B (en) * | 1953-02-14 | 1959-07-16 | Siemens Ag | Process for zone-wise remelting of rods and other elongated workpieces |
DE1017795B (en) * | 1954-05-25 | 1957-10-17 | Siemens Ag | Process for the production of the purest crystalline substances, preferably semiconductor substances |
DE1141255B (en) * | 1958-03-05 | 1962-12-20 | Siemens Ag | Process for producing highly purified single-crystalline semiconductor rods |
GB878765A (en) * | 1956-11-05 | 1961-10-04 | Plessey Co Ltd | Improvements in and relating to processes for the manufacture of semiconductor materials |
DE1109154B (en) * | 1957-03-12 | 1961-06-22 | Licentia Gmbh | Process for the production of boron bromide or boron iodide-free silicon bromide or iodide |
NL226998A (en) * | 1957-04-30 | |||
DE1114170B (en) * | 1957-07-03 | 1961-09-28 | Int Standard Electric Corp | Method and device for the production of extremely pure semiconductor material |
US3006734A (en) * | 1957-11-14 | 1961-10-31 | Plessey Co Ltd | Process for preparing pure silicon |
DE1081869B (en) * | 1957-12-03 | 1960-05-19 | Siemens Ag | Process for the production of silicon single crystals |
DE1198321B (en) * | 1958-01-06 | 1965-08-12 | Int Standard Electric Corp | Process for the production of semiconductor material of great purity |
DE1073460B (en) * | 1958-01-11 | 1960-01-21 | LICENTIA Patent-Verwaltungs-G.m.b.H., Frankfurt/M | Process for purifying silane or chlorinated silanes |
US3116175A (en) * | 1958-01-27 | 1963-12-31 | Marvalaud Inc | Method for forming bicrystalline specimens |
US3036892A (en) * | 1958-03-05 | 1962-05-29 | Siemens Ag | Production of hyper-pure monocrystal-line rods in continuous operation |
DE1180346B (en) * | 1958-03-14 | 1964-10-29 | Gustav Weissenberg Dr H C Dr H | Process for producing high-purity crystals, in particular from semiconductor materials |
US3098741A (en) * | 1958-04-03 | 1963-07-23 | Wacker Chemie Gmbh | Process for effecting crucibleless melting of materials and production of shaped bodies therefrom |
DE1181669B (en) * | 1958-06-03 | 1964-11-19 | Wacker Chemie Gmbh | Process for the production of solid connections or alloys |
DE1719025A1 (en) * | 1958-09-20 | 1900-01-01 | ||
DE1154796B (en) * | 1958-12-16 | 1963-09-26 | Western Electric Co | Process for cleaning silicon or germanium compounds |
NL256017A (en) * | 1959-09-23 | 1900-01-01 | ||
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DE1128412B (en) * | 1959-12-17 | 1962-04-26 | Metallgesellschaft Ag | Process for the production of hyperpure silicon by the thermal decomposition of gaseous silicon compounds |
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DE1190918B (en) * | 1960-06-24 | 1965-04-15 | Wacker Chemie Gmbh | Process for the targeted doping of rod-shaped bodies during zone melting |
DE1216842B (en) * | 1960-09-30 | 1966-05-18 | Karl Ernst Hoffmann | Process for the production of the purest silicon and germanium |
DE1245332B (en) * | 1961-09-14 | 1967-07-27 | Gen Electric | Device for the continuous production of single crystals by deposition from the vapor phase |
US3267529A (en) * | 1961-10-04 | 1966-08-23 | Heraeus Gmbh W C | Apparatus for melting metals under high vacuum |
US3239368A (en) * | 1962-04-26 | 1966-03-08 | Nra Inc | Method of preparing thin films on substrates by an electrical discharge |
US3303115A (en) * | 1962-05-31 | 1967-02-07 | Corning Glass Works | Methods for forming materials of high purity by fusion |
DE1258397B (en) * | 1962-11-15 | 1968-01-11 | Siemens Ag | Method for producing a semiconductor arrangement by means of single-crystalline growth of semiconducting layers by means of a transport reaction |
GB1108741A (en) * | 1963-09-19 | 1968-04-03 | Ass Elect Ind | Improvements in and relating to epitaxial layers of semiconductor materials |
DE1244733B (en) * | 1963-11-05 | 1967-07-20 | Siemens Ag | Device for growing monocrystalline semiconductor material layers on monocrystalline base bodies |
DE1248014B (en) * | 1963-12-05 | 1967-08-24 | Siemens Ag | Process for depositing semiconductor material using an electric glow discharge |
FR1492063A (en) * | 1966-04-05 | 1967-08-18 | Commissariat Energie Atomique | Further development of high frequency electric furnaces for the continuous production of electro-cast refractories |
US4068025A (en) * | 1971-03-22 | 1978-01-10 | Brown, Boveri & Company Limited | Method of applying a protective coating to a body |
CH540995A (en) * | 1971-03-22 | 1973-08-31 | Bbc Brown Boveri & Cie | Method for applying a protective layer to a body |
DE2636348A1 (en) * | 1976-08-12 | 1978-02-16 | Wacker Chemitronic | METHOD FOR MANUFACTURING PURE ELEMENTARY SEMICONDUCTOR MATERIAL |
US4102764A (en) * | 1976-12-29 | 1978-07-25 | Westinghouse Electric Corp. | High purity silicon production by arc heater reduction of silicon intermediates |
US4102767A (en) * | 1977-04-14 | 1978-07-25 | Westinghouse Electric Corp. | Arc heater method for the production of single crystal silicon |
US4102766A (en) * | 1977-04-14 | 1978-07-25 | Westinghouse Electric Corp. | Process for doping high purity silicon in an arc heater |
JPS60246208A (en) * | 1984-05-21 | 1985-12-05 | Toshiba Tungaloy Co Ltd | Preparation of boron nitride |
JPS63222011A (en) * | 1987-03-11 | 1988-09-14 | Mitsubishi Metal Corp | Production of polycrystal silicon |
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CN111574909B (en) * | 2020-04-23 | 2021-11-02 | 华北电力大学(保定) | Preparation method of breakdown-resistant epoxy resin-boron nitride composite material |
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- 1954-05-25 DE DES39318A patent/DE1017795B/en active Pending
- 1954-06-13 DE DES39578A patent/DE976899C/en not_active Expired
- 1954-09-15 DE DES40843A patent/DE1042539B/en active Pending
- 1954-10-21 CH CH355220D patent/CH355220A/en unknown
- 1954-10-21 CH CH362061D patent/CH362061A/en unknown
- 1954-10-26 NL NL191838A patent/NL105537C/xx active
- 1954-10-26 FR FR1131422D patent/FR1131422A/en not_active Expired
- 1954-10-26 GB GB30885/54A patent/GB795191A/en not_active Expired
-
1955
- 1955-05-20 US US509980A patent/US2992984A/en not_active Expired - Lifetime
- 1955-05-23 GB GB14816/55A patent/GB812818A/en not_active Expired
- 1955-05-25 FR FR1125277D patent/FR1125277A/en not_active Expired
- 1955-06-06 DE DES44220A patent/DE1023889B/en active Pending
-
1958
- 1958-04-30 DE DES58066A patent/DE1151782B/en active Pending
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1959
- 1959-04-06 GB GB11585/59A patent/GB890230A/en not_active Expired
- 1959-04-16 US US806882A patent/US2999737A/en not_active Expired - Lifetime
- 1959-04-17 FR FR792433A patent/FR1220648A/en not_active Expired
- 1959-04-23 CH CH7245559A patent/CH376584A/en unknown
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Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3205046A (en) * | 1959-06-05 | 1965-09-07 | Ind De Pierres Scient Hrand Dj | Rotary arbor for making synthetic stone |
US3129059A (en) * | 1960-04-27 | 1964-04-14 | Wacker Chemie Gmbh | Process for manufacturing high purity gallium arsenide |
US3224844A (en) * | 1961-03-01 | 1965-12-21 | Philips Corp | Zone-melting method for metal compounds |
US3245761A (en) * | 1962-10-11 | 1966-04-12 | Norton Co | Apparatus for making magnesium oxide crystals |
US3261722A (en) * | 1962-12-12 | 1966-07-19 | Siemens Ag | Process for preparing semiconductor ingots within a depression |
US3351433A (en) * | 1962-12-12 | 1967-11-07 | Siemens Ag | Method of producing monocrystalline semiconductor rods |
US3259468A (en) * | 1963-05-02 | 1966-07-05 | Monsanto Co | Slim crystalline rod pullers with centering means |
US3519394A (en) * | 1965-02-10 | 1970-07-07 | Ugine Kuhlmann | Apparatus for the fabrication of a synthetic ruby |
US3293002A (en) * | 1965-10-19 | 1966-12-20 | Siemens Ag | Process for producing tape-shaped semiconductor bodies |
US3634045A (en) * | 1967-04-14 | 1972-01-11 | Atomic Energy Authority Uk | Growing of crystals using electron beam heating and annealize |
US3494742A (en) * | 1968-12-23 | 1970-02-10 | Western Electric Co | Apparatus for float zone melting fusible material |
US4087313A (en) * | 1975-11-28 | 1978-05-02 | Joseph Beril Milstein | Process and apparatus for preparation of single crystals and textured polycrystals |
Also Published As
Publication number | Publication date |
---|---|
GB812818A (en) | 1959-04-29 |
DE976899C (en) | 1964-07-23 |
FR1131422A (en) | 1957-02-21 |
DE1017795B (en) | 1957-10-17 |
DE1023889B (en) | 1958-02-06 |
FR1220648A (en) | 1960-05-25 |
GB890230A (en) | 1962-02-28 |
CH376584A (en) | 1964-04-15 |
DE1042539B (en) | 1958-11-06 |
CH362061A (en) | 1962-05-31 |
CH355220A (en) | 1961-06-30 |
US2992984A (en) | 1961-07-18 |
FR1125277A (en) | 1956-10-29 |
GB795191A (en) | 1958-05-21 |
NL105537C (en) | 1963-08-15 |
DE1151782B (en) | 1963-07-25 |
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