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WO1997036822A1 - Procede et appareil de mise en croissance de cristaux allonges - Google Patents

Procede et appareil de mise en croissance de cristaux allonges Download PDF

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Publication number
WO1997036822A1
WO1997036822A1 PCT/IL1997/000112 IL9700112W WO9736822A1 WO 1997036822 A1 WO1997036822 A1 WO 1997036822A1 IL 9700112 W IL9700112 W IL 9700112W WO 9736822 A1 WO9736822 A1 WO 9736822A1
Authority
WO
WIPO (PCT)
Prior art keywords
crystal
magnetic field
growing crystal
growing
parameter
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.)
Ceased
Application number
PCT/IL1997/000112
Other languages
English (en)
Inventor
Moshe Zarudi
Izida Tchernina
Alexander Katsen
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.)
ELMATEC Ltd
Original Assignee
ELMATEC Ltd
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
Application filed by ELMATEC Ltd filed Critical ELMATEC Ltd
Priority to AU20418/97A priority Critical patent/AU2041897A/en
Publication of WO1997036822A1 publication Critical patent/WO1997036822A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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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
    • C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
    • C30B25/02—Epitaxial-layer growth
    • C30B25/10—Heating of the reaction chamber or the substrate
    • 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
    • C01B33/021—Preparation
    • C01B33/027—Preparation by decomposition or reduction of gaseous or vaporised silicon compounds other than silica or silica-containing material
    • C01B33/035—Preparation by decomposition or reduction of gaseous or vaporised silicon compounds other than silica or silica-containing material by decomposition or reduction of gaseous or vaporised silicon compounds in the presence of heated filaments of silicon, carbon or a refractory metal, e.g. tantalum or tungsten, or in the presence of heated silicon rods on which the formed silicon is deposited, a silicon rod being obtained, e.g. Siemens process
    • 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
    • C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
    • 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
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/02—Elements
    • C30B29/06—Silicon

Definitions

  • the present invention relates to the technology of growing crystals in general, and particularly of producing an extended crystal rod of a semiconductor material by depositing on a surface thereof the semicon- ductor material from an appropriate reaction gas containing the same.
  • the further heating includes producing eddy currents within the growing crystal.
  • the eddy currents are induced by an alternating magnetic field of a predetermined frequency fhop so as to provide a skin effect in the growing crystal.
  • the at least one measured parameter is, preferably, a radius R of the growing crystal.
  • the disconnecting of the supply of the conductive current is effected at once the radius R of the growing crystal becomes of about 25 mm.
  • the measuring of the radius R is carried out by suitable sensor means, which may be a tenso-sensor for measuring a weight force P of the growing crystal.
  • the frequency of the alternating magnetic field fa is previously determined according to the following relationship:
  • Kp is a coefficient characterizing a mathematical connection between the wight force P and the radius R;
  • K ⁇ is a coefficient characterizing magnetic properties of the semicon- ductor material
  • K ⁇ is a skin-effect coefficient determined as a ratio ⁇ /R, wherein ⁇ is a depth of penetration of the alternating magnetic field into the growing crystal;
  • ⁇ TT is an electro-conductivity of the semiconductor material as a function of temperature T.
  • the method may further comprise the step of reducing the weight force P of the growing crystal.
  • this is effected by means of creating a travelling magnetic field so as to provide a movement of waves thereof in a direction opposite to the direction of the weight force P of the growing crystal.
  • a frequency of the travelling magnetic field ft should be less than the frequency of the alternating magnetic field f n .
  • an apparatus for producing an extended crystal formed of a semiconductor material grown on an initial rod formed of a seed crystal comprising:
  • a conductive current supply source for supplying the conductive current to pass through the crystal
  • - sensor means for measuring at least one parameter of the crystal and generating data representative thereof
  • control means coupled to the sensor means for processing the data representative of said at least one measured parameter so as to deter ⁇ mine whether or nor said parameter has reached a predetermined value thereof; - an additional heat source selectively actuated by the control means for heating the crystal so as to provide a substantially uniform temperature distribution within a whole volume of the growing crystal
  • the apparatus further includes a compensation means for reducing the weight force P of the growing crystal
  • FIG. 1 is a schematic cross-section view of an apparatus according to the invention
  • Fig. 2 is a schematic cross-section of the apparatus of Fig 1 taken along line A-A, and
  • Figs. 3a-3b illustrate a flow diagram of the principal steps of operation of the apparatus of Fig 1
  • an apparatus comprising a cylind ⁇ cally-shaped vessel 4 which is heat- insulated
  • the vessel 4 is closed by an upper cover 2 and a lower cover 9 at its opposite ends
  • Two pairs of openings 2a and 9a are provided in the covers 2 and 9, respectively
  • An extended rod 3 formed of a seed silicon crystal, typically of 5-10 mm in its diameter, is axially mounted inside the vessel 4 in a manner to be supported by its opposite ends in a pair of clamps 8a and 8b, which are freely movable relative to the vessel 4 along an axis thereof.
  • An appropriate power source 11 is coupled to the rod 3 in a conventional manner through a power regulator 12 so as to supply a conductive current of the commercial frequency passing through the rod 3.
  • the conductive current thus provides a heating of the rod 3.
  • Two gaseous reagents, Si n H m Cl p and H 2 are injected into the vessel 4 through the openings 9a and, when passing through a clearance 6 provided between a surface of the rod 3 and an inner surface of the vessel 4, react in a manner to educe pure silicon Si, which, in turn, is continuously deposited on the heated rod 3.
  • Resulted reaction products are ejected from the vessel 4 through the openings 2a. All these components and their functional features are known per se and, therefore, need not be more specifically described, except to note that this is carried out at surface temperature of the grown crystal 3a of about 1100-1150°C corresponding to the diameter of the crystal about 50 mm.
  • One of the essential features of the present invention is provision of an inductor 7 coupled to a power source 19 of alternating currents.
  • the alternating currents create an alternating magnetic field (AMF), which, in turn, induces eddy currents within the growing crystal 3a.
  • the inductor 7 is configured like a spiral formed of a plurality of spaced turns 22, and mounted in a manner to encompass the vessel 4 along its length, which is better shown in Fig. 2.
  • an inductor 5 which is coupled to a power source 14 for creating a travelling magnetic field (TMF) and is mounted in a manner to encompass the inductor 7 along its length and, thereby, the crystal 3a.
  • the inductor 5 is similarly comprised of spaced turns 21 so as to form a multiphase winding which is placed in a multiradial magnetic circuit 20.
  • the turns 21 and 22 of the inductors 5 and 7, respectively, are formed of electro-conductive and water- cooled tubes as self-explanatory shown in Fig. 1.
  • an optic sensor 15 of a known type mounted for measuring a surface temperature of the growing crystal 3a.
  • the sensor 15 has an imaging unit 16 which protrudes through the spaces between the turns 21 and 22 of the inductors 5 and 7 and is capable of observing the surface of the crystal 3a through a transparent window 4' made in the vessel 4.
  • the sensor 15 is electrically connected to the power source 19 through a processing unit 17 and a temperature regulator 18.
  • the lower supporting clamp 8b is supported on a tenso-electric sensor 10.
  • the sensor 10 may also be of any known type adapted for continuously measuring a weight force P by which the growing crystal 3a presses onto the sensor 10, and generating data representative thereof. By that reason the supporting clamps 8a and 8b are made vertically movable relative to the vessel 4, as specifically indicated above.
  • a regulator 13 Interconnected between the sensor 10 and the processing means 17 is a regulator 13, which is further coupled to the power source 14 of the inductor 5.
  • the skin effect is characterized by the following factor:
  • K ⁇ is a coefficient characterizing magnetic properties of the crystal material, that is silicon Si in the present example
  • f a is a frequency of alternation of the AMF
  • ⁇ iT is the electro-conductivity of the crystal material (Si) being a function of its temperature T.
  • the crystal 3a is considered to be of relatively small diameters such as 5-10 mm to 50 mm. Therefore, the surface temperature T of the crystal 3a is kept to be the same within its volume.
  • the radius R of the crystal 3a is calculated by the processing means 17 which are inputted by the data representative of the measured weight force P of the crystal 3a coming from the sensor 10.
  • Fig. 3 a flow diagram of the principal steps of operation of the apparatus 1, utilizing physical sense of the above mathe ⁇ matical dependence (5), is illustrated.
  • the weight force P is continuously measured by the tenso-sensor 10.
  • the weight force P reaches a predetermined value thereof correspond ⁇ ing to a certain value of the crystal's radius R, which is appropriately detected by the processor 17, the supply of the conductive current is discontinued, namely the power source 11 is switched off.
  • the PCML97/00112 the PCML97/00112
  • inductor 7 is actuated.
  • the inductor 7 creates the AMF of such a frequency f a that the clearly expressed skin effect takes place.
  • heating sources of the crystal 3a are thus moved from its central region to the surface region thereof.
  • the frequency f a is found to be of 10kHz and higher. It should be noted that in order to realize the method of the present invention there is no need to resort to a high frequency heating, that decreases an expenditure level.
  • the inductor 5 is actuated. Obviously, the inductor 5 may be actuated earlier, simultaneously with the actuation of the inductor 7. Further, the weight force P and the temperature T are concurrently measured by the tenso-sensor 10 and the optic sensor 15, respectively. This process enables to produce crystals of 300 mm and more in diameter.
  • the inductor 5 when actuated, creates an electromagnetic force F directed against the crystal's weight force P.
  • Direction of movement of the TMF waves coincides with the direction of the force F, while its wave length ⁇ equals to double distance, ⁇ , between those turns 21 of the inductor 5 which contain conductors of the same phase and in which currents are of opposite directions.
  • the TMF In contrast to the AMF which acts on the surface region of the growing crystal 3a, the TMF should, practically, act on the whole volume of the crystal 3a. If a frequency f, of the TMF is appropriately previously chosen, or changed during the process when the depth of penetration of TMF into the crystal 3a approaches to the radius R of the crystal 3a, the above formula (2) allows to conclude the following:
  • the frequency of the TMF is found to be of about 2-5 kHz.
  • the surface temperature T is measured by the optic sensor 15 and the data representative thereof is transmitted into the processing unit 17 as described above.
  • the degree of compensation K c is variable from 0 to 1.
  • K z is a coefficient which value depends on parameters of the magnetic circuit 20 and is, therefore, constant during the operation of the apparatus 1; I is a current in the inductor 5.
  • the optic sensor 15 may be replaced by another kind of sensing means adapted for measuring the surface temperature of the crystal.
  • the apparatus 1 may be easily modified to be employed for producing a silicon monocrystal from the polycrystal thereof due to the provision of the TMF inductor 5 reducing the weight force of the crystal in a non-contact manner and, thereby, eliminating one of the major problems of conventional systems of the kind associated with undesirable increase of crystal's weight force.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

Procédé et appareil de production d'un cristal allongé formé d'un matériau semi-conducteur, par dépôt, sur la surface d'une tige initiale composée d'un germe cristallin, de particules d'un matériau semi-conducteur provenant d'un gaz réactif contenant ce matériau. On chauffe la tige initiale en faisant passer un courant conducteur à travers elle. On mesure au moins un paramètre du cristal mis en croissance afin de déterminer si ce paramètre présente une valeur préétablie. Si c'est le cas, on déconnecte l'alimentation en courant conducteur et on chauffe à nouveau le cristal en croissance avec une répartition de température sensiblement uniforme dans tout le volume dudit cristal. Ce chauffage supplémentaire est assuré par des courants parasites produits dans le cristal et induits par un champ magnétique alternatif d'une fréquence prédéterminée, de sorte qu'un effet pelliculaire soit produit dans le cristal en croissance. Une charge pondérale du cristal peut ensuite être réduite au moyen d'un champ magnétique mobile créé de façon à entraîner un mouvement des ondes dans le sens opposé à celui de la charge pondérale.
PCT/IL1997/000112 1996-04-02 1997-03-28 Procede et appareil de mise en croissance de cristaux allonges Ceased WO1997036822A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU20418/97A AU2041897A (en) 1996-04-02 1997-03-28 Method and apparatus for growing extended crystals

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IL117770 1996-04-02
IL11777096A IL117770A0 (en) 1996-04-02 1996-04-02 Method and apparatus for growing of extended crystals

Publications (1)

Publication Number Publication Date
WO1997036822A1 true WO1997036822A1 (fr) 1997-10-09

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PCT/IL1997/000112 Ceased WO1997036822A1 (fr) 1996-04-02 1997-03-28 Procede et appareil de mise en croissance de cristaux allonges

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AU (1) AU2041897A (fr)
IL (1) IL117770A0 (fr)
WO (1) WO1997036822A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6221155B1 (en) 1997-12-15 2001-04-24 Advanced Silicon Materials, Llc Chemical vapor deposition system for polycrystalline silicon rod production
US6544333B2 (en) 1997-12-15 2003-04-08 Advanced Silicon Materials Llc Chemical vapor deposition system for polycrystalline silicon rod production
EP2100851A2 (fr) 2008-03-10 2009-09-16 AEG Power Solutions B.V. Dispositif et procédé de production d'une répartition régulière de température dans des tiges de silicium lors d'un procédé de séparation
CN101559948B (zh) * 2008-03-10 2014-02-26 安奕极电源系统有限责任公司 在沉积工艺期间在硅棒中产生均匀温度分布的装置和方法
DE102015122248A1 (de) * 2015-12-18 2017-06-22 Christian Menzel Reaktor und Verfahren zum Aufwachsen von Silizium
WO2020125932A1 (fr) * 2018-12-17 2020-06-25 Wacker Chemie Ag Procédé de production de silicium polycristallin

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3342161A (en) * 1961-11-27 1967-09-19 Siemens Ag Apparatus for pyrolytic production of semiconductor material
US3367303A (en) * 1963-05-29 1968-02-06 Monsanto Co Chemical equipment
US3502516A (en) * 1964-11-06 1970-03-24 Siemens Ag Method for producing pure semiconductor material for electronic purposes
US3980042A (en) * 1972-03-21 1976-09-14 Siemens Aktiengesellschaft Vapor deposition apparatus with computer control
US4426408A (en) * 1978-07-19 1984-01-17 Siemens Aktiengesellschaft Method of deposition of silicon in fine crystalline form

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3342161A (en) * 1961-11-27 1967-09-19 Siemens Ag Apparatus for pyrolytic production of semiconductor material
US3367303A (en) * 1963-05-29 1968-02-06 Monsanto Co Chemical equipment
US3502516A (en) * 1964-11-06 1970-03-24 Siemens Ag Method for producing pure semiconductor material for electronic purposes
US3980042A (en) * 1972-03-21 1976-09-14 Siemens Aktiengesellschaft Vapor deposition apparatus with computer control
US4426408A (en) * 1978-07-19 1984-01-17 Siemens Aktiengesellschaft Method of deposition of silicon in fine crystalline form

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6221155B1 (en) 1997-12-15 2001-04-24 Advanced Silicon Materials, Llc Chemical vapor deposition system for polycrystalline silicon rod production
US6544333B2 (en) 1997-12-15 2003-04-08 Advanced Silicon Materials Llc Chemical vapor deposition system for polycrystalline silicon rod production
US6749824B2 (en) 1997-12-15 2004-06-15 Advanced Silicon Materials Llc Chemical vapor deposition system for polycrystalline silicon rod production
DE19882883B4 (de) * 1997-12-15 2009-02-26 Advanced Silicon Materials LLC, (n.d.Ges.d.Staates Delaware), Moses Lake System für die chemische Abscheidung aus der Gasphase zum Herstellen polykristalliner Siliziumstangen
EP2100851A2 (fr) 2008-03-10 2009-09-16 AEG Power Solutions B.V. Dispositif et procédé de production d'une répartition régulière de température dans des tiges de silicium lors d'un procédé de séparation
EP2100851A3 (fr) * 2008-03-10 2011-02-09 AEG Power Solutions B.V. Dispositif et procédé de production d'une répartition régulière de température dans des tiges de silicium lors d'un procédé de séparation
US8330300B2 (en) 2008-03-10 2012-12-11 Aeg Power Solutions B.V. Device and method for producing a uniform temperature distribution in an object during a precipitation process
CN101559948B (zh) * 2008-03-10 2014-02-26 安奕极电源系统有限责任公司 在沉积工艺期间在硅棒中产生均匀温度分布的装置和方法
DE102015122248A1 (de) * 2015-12-18 2017-06-22 Christian Menzel Reaktor und Verfahren zum Aufwachsen von Silizium
WO2020125932A1 (fr) * 2018-12-17 2020-06-25 Wacker Chemie Ag Procédé de production de silicium polycristallin
US11655541B2 (en) 2018-12-17 2023-05-23 Wacker Chemie Ag Process for producing polycrystalline silicon

Also Published As

Publication number Publication date
IL117770A0 (en) 1996-08-04
AU2041897A (en) 1997-10-22

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