DE1215109B - Method for crucible-free zone melting of semiconductor material - Google Patents

Method for crucible-free zone melting of semiconductor material

Info

Publication number
DE1215109B
DE1215109B DES64464A DES0064464A DE1215109B DE 1215109 B DE1215109 B DE 1215109B DE S64464 A DES64464 A DE S64464A DE S0064464 A DES0064464 A DE S0064464A DE 1215109 B DE1215109 B DE 1215109B
Authority
DE
Germany
Prior art keywords
rod
coil
diameter
current
crucible
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
DES64464A
Other languages
German (de)
Inventor
Dr Wolfgang Keller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to NL135666D priority Critical patent/NL135666C/xx
Priority to BE594105D priority patent/BE594105A/xx
Priority to NL252591D priority patent/NL252591A/xx
Application filed by Siemens AG filed Critical Siemens AG
Priority to DES64464A priority patent/DE1215109B/en
Priority to DES66492A priority patent/DE1277813B/en
Priority to GB21453/60A priority patent/GB899688A/en
Priority to CH774460A priority patent/CH389249A/en
Priority to US49330A priority patent/US3265470A/en
Priority to FR835936A priority patent/FR1265080A/en
Publication of DE1215109B publication Critical patent/DE1215109B/en
Pending legal-status Critical Current

Links

Classifications

    • 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
    • C30B13/00—Single-crystal growth by zone-melting; Refining by zone-melting
    • C30B13/28—Controlling or regulating
    • C30B13/30—Stabilisation or shape controlling of the molten zone, e.g. by concentrators, by electromagnetic fields; Controlling the section of the crystal
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating
    • H05B6/06—Control, e.g. of temperature, of power
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating
    • H05B6/22—Furnaces without an endless core
    • H05B6/30—Arrangements for remelting or zone melting
    • 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
    • Y10T117/00—Single-crystal, oriented-crystal, and epitaxy growth processes; non-coating apparatus therefor
    • Y10T117/10—Apparatus
    • Y10T117/1004—Apparatus with means for measuring, testing, or sensing
    • Y10T117/1008—Apparatus with means for measuring, testing, or sensing with responsive control means
    • 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
    • Y10T117/00—Single-crystal, oriented-crystal, and epitaxy growth processes; non-coating apparatus therefor
    • Y10T117/10—Apparatus
    • Y10T117/1024—Apparatus for crystallization from liquid or supercritical state
    • Y10T117/1076—Apparatus for crystallization from liquid or supercritical state having means for producing a moving solid-liquid-solid zone
    • Y10T117/1084—Apparatus for crystallization from liquid or supercritical state having means for producing a moving solid-liquid-solid zone having details of a stabilizing feature

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • General Induction Heating (AREA)
  • Liquid Deposition Of Substances Of Which Semiconductor Devices Are Composed (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Description

BUNDESREPUBLIK DEUTSCHLANDFEDERAL REPUBLIC OF GERMANY

deutsches '///znZWl· Patentamt Int. α..german '/// znZWl · Patent Office Int. α ..

BOIdBOId

AUSLEGESCHRIFTEDITORIAL

Deutsche Kl,; 12 c- 2German Kl; 12 c- 2

Nummer: 1215 109Number: 1215 109

Aktenzeichen: S 64464IV c/12 cFile number: S 64464IV c / 12 c

Anmeldetag: 17. August 1959 Filing date: August 17, 1959

Auslegetag: 28, April 1966Opened on: April 28, 1966

Es ist bereits ein Verfahren zum tiegelfreien Zonenschmelzen von Halbleitermaterial vorgeschlagen worden, bei dem eine Schmelzzone zwischen den beiden gehalterten Enden eines Halbleiterstabes in Richtung der Stabachse entlang geführt wird, die mittels induktiver Erhitzung durch eine von einem Hochfrequenzgenerator gespeiste, den Stab ringförmig umgebende Spule erzeugt wird, und bei welchem der in die Spule eingespeiste, von dem Durchmesser des Stabes abhängige Strom zur Steuerung einer Einrichtung verwendet wird, welche die beiden Halterungen in der Weise einander nähert bzw. voneinander entfernt, daß der Strom in der Hochfrequenzspule auf einen gewünschten Wert zurückgeführt wird, wobei der Blindstrom der Heizspule mit Hilfe einer parallelgeschalteten Kapazität auskompensiert wird.A method for crucible-free zone melting of semiconductor material has already been proposed has been, in which a melting zone between the two supported ends of a semiconductor rod in Direction of the rod axis is guided along, by means of inductive heating by one of a High-frequency generator fed, the rod ring-shaped surrounding coil is generated, and in which the current fed into the coil, dependent on the diameter of the rod, for controlling a device is used, which the two brackets in such a way approaches each other or from each other removes that the current in the high frequency coil is returned to a desired value the reactive current of the heating coil is compensated with the help of a parallel connected capacitance will.

Die Erfindung betrifft eine Verbesserung dieses Verfahrens, die erfindungsgemäß dadurch erreicht wird, daß ein gewünschter Stabdurchmesser durch Einstellung der Frequenz des Hochfrequenzgenerators eingestellt wird.The invention relates to an improvement of this method, which is achieved according to the invention that a desired rod diameter by adjusting the frequency of the high frequency generator is set.

An Hand der Zeichnung soll die Erfindung näher erläutert werden. Es ist das Prinzip der Durchmessereinstellung und -regelung schematisch dargestellt. Ein Halbleiterstab 2 ist an seinen Enden in zwei Halterungen 3 und 4 fest eingespannt, von denen die obere 4 in Achsrichtung des Stabes bewegt werden kann. Eine Spule 5 ist um den Halbleiterstab herumgelegt und erzeugt durch induktive Erhitzung eine Schmelzzone 6. Zwecks Kompensation des Blindstromes ist der Spule 5 eine Kapazität 7 parallel geschaltet. Die Spule 5 und die Kapaziät bilden somit einen sekundären Schwingkreis (im folgenden Heizkreis genannt), der an die Ausgangsklemmen 8 eines Hochfrequenzgenerators 9 angekoppelt ist. Der Hochfrequenzgenerator arbeitet zweckmäßigerweise auf einer Flanke der Resonanzkurve des Heizkreises. Der Generator 9 wird an den Klemmen 10 vom Netz her eingespeist. Ein Drehknopf 11 soll symbolisieren, daß die Frequenz des Hochfrequenzgenerators 9 einstellbar ist.The invention is to be explained in more detail with reference to the drawing. It is the principle of diameter adjustment and control shown schematically. A semiconductor rod 2 is at its ends in two holders 3 and 4 firmly clamped, of which the upper 4 can be moved in the axial direction of the rod. A coil 5 is placed around the semiconductor rod and generates a melting zone by inductive heating 6. In order to compensate for the reactive current, a capacitor 7 is connected in parallel to the coil 5. the Coil 5 and the capacitance thus form a secondary oscillating circuit (hereinafter referred to as the heating circuit), which is coupled to the output terminals 8 of a high-frequency generator 9. The high frequency generator expediently works on an edge of the resonance curve of the heating circuit. The generator 9 is fed in from the mains at terminals 10. A knob 11 is intended to symbolize that the frequency of the high frequency generator 9 is adjustable.

Der Anodenstrom des Generators ist von der aufgenommenen Leistung des Heizkreises abhängig und damit von dem Durchmesser des Halbleiterstabes, da eine Änderung des Stabdurchmessers eine Änderung der Koppelung zwischen Spule 5 und Schmelzzone 6 bewirkt. Eine solche Änderung des Anodenstromes wird durch das Meßgerät 12 angezeigt und ruft an dem Widerstand 13 einen Spannungsabfall hervor. Dieser Widerstand wird so eingestellt, daß ein Anodenstrom, wie er sich bei dem gewünschten Durch-The anode current of the generator depends on the power consumed by the heating circuit and hence from the diameter of the semiconductor rod, since a change in the rod diameter is a change the coupling between coil 5 and melting zone 6 causes. Such a change in the anode current is indicated by the measuring device 12 and causes a voltage drop across the resistor 13. This resistance is set in such a way that an anode current, as it is at the desired through-

Verfahren zum tiegelfreien Zonenschmelzen von
HalbleitermaterialProcess for crucible-free zone melting of
Semiconductor material

Anmelder:Applicant:

Siemens-Schuckertwerke Aktiengesellschaft,Siemens-Schuckertwerke Aktiengesellschaft,

Berlin und Erlangen,Berlin and Erlangen,

Erlangen, Werner-von-Siemens-Str. 50Erlangen, Werner-von-Siemens-Str. 50

Als Erfinder benannt:Named as inventor:

Dr. Wolfgang Keller, PretzfeldDr. Wolfgang Keller, Pretzfeld

messer des Halbleiterstabes einstellt, einen Spannungsabfall gleich der Spannung der Batterie 14 bewirkt. Dies führt dazu, daß das gepolte Relais 15 in Ruhestellung liegt.knife of the semiconductor rod sets, a voltage drop equal to the voltage of the battery 14 causes. This results in the polarized relay 15 in Rest position is.

Ändert sich nun der Stabdurchmesser, so ändert sich auch der Anodenstrom und damit der Spannungsabfall an dem Widerstand 13. Das Relais 15 zieht an, der Kontakt 16 schließt in der einen Richtung und schaltet den Motor 17 ein. Über ein Zahnrad 18 wird eine Zahnstange 19 betätigt, mit deren Hilfe die obere Stabhalterung 4 entweder der unteren Stabhalterung 3 genähert oder von dieser entfernt wird. Durch entsprechende Polung von Relais 15 und Motor Ϊ7 läßt sich erreichen, daß der Motor 17 immer in der richtigen Richtung umläuft, d. h., daß bei zu großem Stabdurchmesser ein Abziehen und bei zu kleinem Stabdurchmesser ein Stauchen der Schmelzzone erfolgt. Auf diese Weise kann man also beim Zonenschmelzen von Halbleiterstäben mit der Erzielung eines definierten Durchmessers rechnen.If the rod diameter now changes, the anode current and thus the voltage drop also change at the resistor 13. The relay 15 picks up, the contact 16 closes in one direction and switches on the motor 17. A rack 19 is actuated via a gear 18, with the Help the upper rod holder 4 either approached the lower rod holder 3 or removed from it will. Corresponding polarity of relay 15 and motor Ϊ7 ensures that motor 17 always runs in the right direction, d. This means that if the rod diameter is too large, pulling off and If the rod diameter is too small, the melt zone will be compressed. So this way you can When zone melting of semiconductor rods, expect a defined diameter to be achieved.

Wie sich nun bei näherer Untersuchung des Verfahrens herausstellte, besteht bei gegebenem Heizkreis und konstanter Kopplung zwischen Heizkreis und Generator ein eindeutiger Zusammenhang zwischen Generatorfrequenz, Anodenstrom und Stabdurchmesser. Man kann also durch Einstellen bestimmter Werte von Frequenz und Anodenstrom bestimmte reproduzierbare Stabdurchmesser erzwingen. Die Frequenzskala des Generators kann gleich in Durchmesserangaben geeicht werden. Es zeigte sich, daß der Stabdurchmesser wesentlich intensiver auf eine Frequenzänderung als auf eine Stromänderung reagierte. So trat bei einer Frequenzänderung von 1% nach oben oder unten eine Veränderung desAs it turned out on closer examination of the process, there is a given heating circuit and constant coupling between heating circuit and generator a clear connection between Generator frequency, anode current and rod diameter. So by setting certain Values of frequency and anode current force certain reproducible rod diameters. The frequency scale of the generator can also be calibrated in terms of diameter. It was found, that the rod diameter is much more sensitive to a change in frequency than to a change in current responded. With a frequency change of 1% upwards or downwards, there was a change in the

609 560/333609 560/333

Durchmessers von etwa 6 % auf. Demgegenüber veränderte eine Anodenstromabweichung von 5% den Stabdurchmesser nur um etwa 1%.Diameter of about 6%. In contrast, an anode current deviation of 5% changed the Rod diameter by only about 1%.

Claims (1)

Patentanspruch:Claim: Verfahren zum tiegelfreien Zonenschmelzen von Halbleitermaterial, bei dem eine Schmelzzone zwischen den beiden gehalterten Enden eines Halbleiterstabes in Richtung der Stabachse entlanggeführt wird, die mittels induktiver Erhitzung durch eine von einem Hochfrequenzgenerator gespeiste, den Stab ringförmig umgebende Spule erzeugt wird, und bei welchem der in die Spule eingespeiste, von dem Durchmesser des Stabes abhängige Strom zur Steuerung einer Einrichtung verwendet wird, welche die beiden Halterungen in der Weise einander nähert bzw. voneinander entfernt, daß der Strom in der Hochfrequenzspule auf einen gewünschten Wert zurückgeführt wird, wobei der Blindstrom der Heizspule mit Hilfe einer parallelgeschalteten Kapazität auskompensiert wird, dadurch gekennzeichnet, daß ein gewünschter Stabdurchmesser durch Einstellung der Frequenz des Hochfrequenzgenerators eingestellt wird.Method for crucible-free zone melting of semiconductor material, in which a melting zone guided along between the two supported ends of a semiconductor rod in the direction of the rod axis that is generated by means of inductive heating by a high-frequency generator The coil surrounding the rod in a ring shape is generated, and in which the coil is inserted fed in current, dependent on the diameter of the rod, for controlling a device is used, which the two brackets in such a way approaches each other or from each other removes that the current in the high frequency coil is returned to a desired value, whereby the reactive current of the heating coil is compensated with the help of a capacitance connected in parallel is, characterized in that a desired rod diameter by setting the frequency of the high frequency generator is set. In Betracht gezogene ältere Patente:
Deutsches Patent Nr. 1153 908.Legacy Patents Considered:
German Patent No. 1153 908. Hierzu 1 Blatt Zeichnungen For this purpose, 1 sheet of drawings 609 560/333 4.66 © Bundesdruckerei Berlin609 560/333 4.66 © Bundesdruckerei Berlin
DES64464A 1959-08-17 1959-08-17 Method for crucible-free zone melting of semiconductor material Pending DE1215109B (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
NL135666D NL135666C (en) 1959-08-17
BE594105D BE594105A (en) 1959-08-17
NL252591D NL252591A (en) 1959-08-17
DES64464A DE1215109B (en) 1959-08-17 1959-08-17 Method for crucible-free zone melting of semiconductor material
DES66492A DE1277813B (en) 1959-08-17 1959-12-31 Method for crucible-free zone melting of semiconductor material
GB21453/60A GB899688A (en) 1959-08-17 1960-06-17 An automatically controlled process for melting a rod of semi-conductor material zone-by-zone
CH774460A CH389249A (en) 1959-08-17 1960-07-07 Method for crucible-free zone melting of semiconductor material
US49330A US3265470A (en) 1959-08-17 1960-08-12 Method and apparatus for floating-zone melting of semiconductor material
FR835936A FR1265080A (en) 1959-08-17 1960-08-16 Zonal crucible-less melting process of semiconductor materials

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DES64464A DE1215109B (en) 1959-08-17 1959-08-17 Method for crucible-free zone melting of semiconductor material
DES66492A DE1277813B (en) 1959-08-17 1959-12-31 Method for crucible-free zone melting of semiconductor material

Publications (1)

Publication Number Publication Date
DE1215109B true DE1215109B (en) 1966-04-28

Family

ID=25995811

Family Applications (2)

Application Number Title Priority Date Filing Date
DES64464A Pending DE1215109B (en) 1959-08-17 1959-08-17 Method for crucible-free zone melting of semiconductor material
DES66492A Pending DE1277813B (en) 1959-08-17 1959-12-31 Method for crucible-free zone melting of semiconductor material

Family Applications After (1)

Application Number Title Priority Date Filing Date
DES66492A Pending DE1277813B (en) 1959-08-17 1959-12-31 Method for crucible-free zone melting of semiconductor material

Country Status (6)

Country Link
US (1) US3265470A (en)
BE (1) BE594105A (en)
CH (1) CH389249A (en)
DE (2) DE1215109B (en)
GB (1) GB899688A (en)
NL (2) NL252591A (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3321299A (en) * 1964-10-13 1967-05-23 Monsanto Co Apparatus and process for preparing semiconductor rods
DK116145B (en) * 1965-07-09 1969-12-15 Siemens Ag Plant for inductive heating of semiconductor material.
NL6512921A (en) * 1965-10-06 1967-04-07
US3446602A (en) * 1965-11-13 1969-05-27 Nippon Electric Co Flame fusion crystal growing employing vertically displaceable pedestal responsive to temperature
US3660062A (en) * 1968-02-29 1972-05-02 Siemens Ag Method for crucible-free floating zone melting a crystalline rod, especially of semi-crystalline material
US3776703A (en) * 1970-11-30 1973-12-04 Texas Instruments Inc Method of growing 1-0-0 orientation high perfection single crystal silicon by adjusting a focus coil
DE2220519C3 (en) * 1972-04-26 1982-03-11 Siemens AG, 1000 Berlin und 8000 München Process for crucible-free zone melting of semiconductor rods
GB1434527A (en) * 1972-09-08 1976-05-05 Secr Defence Growth of crystalline material
DK142586B (en) * 1977-07-07 1980-11-24 Topsil As Apparatus for zone melting of a semiconductor rod.
US4857689A (en) * 1988-03-23 1989-08-15 High Temperature Engineering Corporation Rapid thermal furnace for semiconductor processing

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2470443A (en) * 1944-07-21 1949-05-17 Mittelmann Eugene Means for and method of continuously matching and controlling power for high-frequency heating of reactive loads
US2508321A (en) * 1945-09-05 1950-05-16 Raymond M Wilmotte Method and means of controlling electronic heating
US2691732A (en) * 1948-12-07 1954-10-12 Westinghouse Electric Corp Radio frequency generator
DE1061527B (en) * 1953-02-14 1959-07-16 Siemens Ag Process for zone-wise remelting of rods and other elongated workpieces
US2972525A (en) * 1953-02-26 1961-02-21 Siemens Ag Crucible-free zone melting method and apparatus for producing and processing a rod-shaped body of crystalline substance, particularly semiconductor substance
US2868902A (en) * 1958-03-19 1959-01-13 Prec Metalsmiths Inc Induction heater control
DE1153908B (en) * 1958-04-22 1963-09-05 Siemens Ag Method and device for crucible-free zone melting with changing the spacing of the rod ends
GB904100A (en) * 1959-09-11 1962-08-22 Siemens Ag A process for zone-by-zone melting of a rod of semi-conductor material using an induction coil as the heating means and an automatic arrangement for controlling the current through the coil

Also Published As

Publication number Publication date
BE594105A (en)
NL135666C (en)
GB899688A (en) 1962-06-27
CH389249A (en) 1965-03-15
NL252591A (en)
DE1277813B (en) 1968-09-19
US3265470A (en) 1966-08-09

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