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US3194691A - Method of manufacturing rod-shaped crystals of semi-conductor material - Google Patents

Method of manufacturing rod-shaped crystals of semi-conductor material Download PDF

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Publication number
US3194691A
US3194691A US53692A US5369260A US3194691A US 3194691 A US3194691 A US 3194691A US 53692 A US53692 A US 53692A US 5369260 A US5369260 A US 5369260A US 3194691 A US3194691 A US 3194691A
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Prior art keywords
crystal
directions
seed
rod
growing
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Expired - Lifetime
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US53692A
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English (en)
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Dikhoff Johannes Aloysiu Maria
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US Philips Corp
North American Philips Co Inc
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US Philips Corp
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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
    • C30B13/00—Single-crystal growth by zone-melting; Refining by zone-melting
    • C30B13/34—Single-crystal growth by zone-melting; Refining by zone-melting characterised by the seed, e.g. by its crystallographic orientation
    • 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
    • C30B11/14—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method characterised by the seed, e.g. its crystallographic orientation
    • 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
    • C30B15/10—Crucibles or containers for supporting the melt
    • C30B15/12—Double crucible methods
    • 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
    • C30B15/36—Single-crystal growth by pulling from a melt, e.g. Czochralski method characterised by the seed, e.g. its crystallographic orientation
    • 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
    • Y10S117/902—Specified orientation, shape, crystallography, or size of seed or substrate

Definitions

  • the invention relates to a method of manufacturing rod-shaped crystals of semi-conductor material having diamond structure by growing a pre-orientated seed crystal from a melt of the material.
  • diamond structure as used herein is to be understood to mean not only a crystal structure comprising one kind of atoms, such as in germanium and silicon, but also a crystal structure comprising several kinds of atoms and exhibiting an analogous arrangement of the atoms in the crystal lattice, such as, for example, the sphalerite or zinc blende lattice.
  • Growing may be effected by various methods, the most usual being the crystal pulling method, the zone melting method and the zone melting method without the use of a crucible, the so-called floating zone method.
  • the rod-shaped, generally monocrystalline crystals obtained can be divided, for example by sawing, into plate-shaped bodies which are used in semiconductor electrode systems, such as transistors, diodes and photoelectric cells.
  • Such a rod-shapedcrystal is required to be homogeneous as far as possible, at least with respect to its specific resitivity. It has been found in practice that in such a rod-shaped crystal the specific resistivity in the transverse directions frequently is not homogeneous, and that in particular the phenomenon may occur that in a generally central part of the crystal extending in the direction of length thereof the specific resistivity differs considerably from that in the adjoining parts of the crystal. Due to this effect, which hereinafter will be referred to as core formation, the specific resistivity values measured at different points through cross sections of the crystal show relative differences exceeding 30% and even 50%.
  • the invention is based on the discovery that the occurrcnce of core formation is related to the orientation of the lattice of the growing crystal. Since generally in semiconductor elect-rode systems plate-shaped single-crystal semi-conductor bodies are used in which the normals to the upper and lower faces coincide with a main crystallographic, direction of the crystal lattice, that is to say a [l(l0]-, [1101- or [UH-direction, and preferably with a [UH-direction, in practice in manufacturing rodshaped crystals the direction of growing is generally chosen as accurately as possible according to such a main crystallographic direction, in most cases according to a [UH-direction, the obtained rod-shaped crystal being subsequently divided, for example by sawing, into slices according to planes extending at right angles to the longitudinal direction of the rod.
  • the invention "ice is based on the discovery that core formation takes place at the point at which in the growing crystal the normal to the solidification frontier or solid-liquid interface coincides with a main crystallographic direction of the crystal, the strongest core formation occurring when this normal coincides with a [MU-direction, and that this undesirable effect can be avoided by choosing the orientation so that at no point the main crystallographic directions are at right angles the to the solidification frontier.
  • the seed crystal is orientated so that the main crystallographic directions of the crystal deviate from the growing direction of the crystal by angles of at least 5.
  • the resultant rod-shaped crystal is sliced into wafers by dividing the rod along planes extending substantially at right angles to one of the main crystallographic directions of the crystal.
  • the solidification frontier of the growing crystal tends to extend in a direction such that locally the normal to this frontier coincides with a [UH-direction, this tendency increasing with increased curvature of the frontier.
  • the minimum angle between the growing direction and the [UH-directions of the crystal preferably are chosen so as to exceed 5 and even to be at least 20.
  • the smallest of the angles between the growing direction and the [UH-directions does not exceed 30, so that the rod-shaped crystal produced can readily be divided into slices according to dividing planes extending at right angles to the [UH-direction associated with this smallest angle.
  • FIGURE 1 shows an apparatus for growing a crystal to a seed crystal by means of the floating-zone method
  • FIGURE 2 shows the orientation of'the crystal of FIGURE 1
  • FIGURE 3 shows an apparatus for pulling a crystal from a melt
  • FIGURE 4 shows the orientation of the crystal of FIGURE 3
  • FIGURE 5 shows an apparatus for zone melting in an elongated crucible
  • FIGURE 6 shows the orientation of the seed crystal of FIGURE 5.
  • reference numeral 1 designates a silicon seed crystal the upper end of which is secured in a holder 2 revolving about its vertical axis X at a speed of revolutions per minute.
  • a silicon rod 3 arranged vertically along the X-axis is secured at its lower end in a holder 4.
  • a molten zone 5 which'is heated by a highfrequency coil 6 symmetrically encircling this zone, themolten material being prevented from flowing down by its high surface tension.
  • the high-frequency coil islowered in the direction indicated by an arrow at a rate of 1 mm. per minute, so that the rod 3 melts gradually and the crystal 1 gradually grows in the vertical direction so as to form a rod.
  • the solidification frontier 7 between the growing seed crystal 1 and the molten zone 5 has a slightly curvedform which is substantially symmetrical with respect to the X-axis.
  • the orientation of the crystal 1 is shown in FIGURE 2 by means of a cube 8 the position of which corresponds to that of a cubic unit cell of the crystal.
  • the [lIIJ-direction 9 (a cube body diagonal) must be assumed to extend parallel to the plane of the drawing.
  • HIM-directions when employed'herein, it includes any and all directions within the cubic crystal corresponding to a cube diagonal, of which there are four, totalling eight directions; and the term [100]- directions similarly indicates any and all directions corresponding to a cubic crystal edge; and the term [110]- directions similarly includesany and all directions corresponding to a face diagonal of the cubic crystal.
  • main crystallographic directions means all the directions corresponding to one of the foregoing [111]-, [100]- or [110] -directions.
  • the rod-shaped crystal obtained in this manner can readily be divided into slices by sawing according to planes at right angles to the [UH-direction 9. If in such a slice the specific resistivity is measured at different points, it
  • FIGURE 3 shows a device for pulling crystals from a melt, reference numeral 11 denoting a graphite crucible arranged on a graphite disc 12 having a rim 13 and disposed on a container 14, so that two chambers 15 and 16 are produced between the crucible 11 and the container 14.
  • the container 14 comprises a cylinder 17 and a piston 18.
  • a narrow duct 19 which is provided in the bottom of the crucible '11 and the upper wall of the container 14 and extends through a rod-shaped intermediate member 20 passing through an aperture 2.1 in the disc 12, the container 14 is in communication with the crucible 11.
  • the assembly is surrounded by a highfrequency coil 22 so that it can be heated. Due to the presence of the graphite disc 12 with the rim 13 and of the chambers 15 and 16, additional heat can be supplied to the bottom of the crucible 11.
  • V highfrequency coil 22
  • the container 14 and the duct 19 are entirely filled with a melt 23 of germanium, which also fills the crucible 11 to r is measured at different points, the measured values may be different but the relative differences are always less than 10%.
  • FIGURE 5 shows an apparatus for producing rodshaped crystals by means of zone melting, in which a quartz crucible 3%? in the form 'of an elongated boat is adapted to be displaced horizontally in its direction of length with respect to-an encirclinghigh-frequency coil 31.
  • the seed crystal 33 leans against an end wall 34 of the crucible so'that its direction of length makes an angle of 10 with the direction of length of the crucible 30.
  • the orientationrof the seed crystal is shown in FIGURE 6 with the aid of a cube 35,'while the [l11]-direction 36 must be assumed to extend parallel to the plane of the drawing.
  • the crucible (FIGURE 5) now is arranged so that the high-frequency coil 31 surrounds the area of contact between the rod 32 and the seed crystal 33 'and subse quently a molten zone 37 is produced at this point byv the coil being energized; Then the crucible is displaced with respect to the coil in the direction indicated-by an arrow at a rate of 2 mm. per minute, so that the molten zone passes through the rod 32 in the direction of length thereof, in which process this rod gradually. melts and the seed crystal 33 grows along the direction of length of the cru proficient to form a rod-shaped crystal-having an orientation as shown in FIGURE 6.
  • The.cr.ystal produced can be divided into slices according to planes extending at right angles to the [111]- direction 27. If, now, in such a slice the specific resistivity nal axis of the growing part of the crystal, the lower part of this frontier being substantially at right angles to a direction 39 in which the crystal grows whereas the upper portion of the frontier greatly deviates from this position. Since the [11l]-direction 36 of the seed crystal deviates from the growth direction 3? (FIGURE 6) through an angle of 10, at no point is it at right angles to the solidification frontier 38 (FIGURE 5) sothat no core formation occurs in the growing crystal. It should be mentioned that in this case the choice of the direction in which the [111]-axis'36 deviates from the growing direction by a comparatively small angle is not arbitrary but directly related to the asymmetrical shape of the solidifi: cation frontier.
  • a method of making generally monocrystalline wafers for use 'in semiconductor devices comprising providing a single seed crystal of semiconductormaterial having a diamond structure and having three main crystiallograpihic directions including the [flu-directions, []-directions, and the []-directions, contacting the seed to a melt of the same semiconductor material which is then translated away. relative to the seed to grow from the seed agenerally rod-shaped crystal, said single seed crystal being oriented relative to the-melt such that its growing direction corresponding to the direction of translation deviates from-all of the said three main crystallographic directions-by an angle of at'least 5, and the smallest angle between a [UH-direction of the seed and the said growing direction.
  • melt-solid interface is oblique to the said three main crystallographic directions and the rodshaped crystal thus grown exhibits more uniform transverse resistivity, and forming monocrystalline wafers from the thusgrown rod-shaped crystal by dividing same along planes extending substantially at rig-ht angles to one of said three main crystallographic directions, said wafers or sections thereof to be incorporated in the devices made.
  • crys tal is grown by zone-melting from the oriented seed.
  • a method of making generally monocrystalline wafers for use in semiconductor devices comprising providing a single seed crystal of semiconductor material having a diamond structure and having three main crystallographic directions including the [111]-directions, [1001-directions, and the [110]-directions, contacting the seed to a melt of the same semiconductor material which is then translated away relative to the seed to grow from the seed a generally rod-shaped crystal, said single seed crystal being oriented relative to the melt such that its 10 growing direction corresponding to the direction of translation deviates from all of the said three main crystallographic directions by an angle of at least 5, and the smallest angle between a [UH-direction of the seed and the said growing direction is between 20 and 30, and such that the melt-solid interface is oblique to the said three main crystallographic directions and the rod-shaped crystal thus grown exhibits more uniform transverse resistivity, and forming monocrystalline wafers from the thus-grown rod-shaped crystal by dividing same along planes extending substantially at right angles to the said 6 [UH-direction forming the

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  • 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)
  • Liquid Deposition Of Substances Of Which Semiconductor Devices Are Composed (AREA)
US53692A 1959-09-18 1960-09-02 Method of manufacturing rod-shaped crystals of semi-conductor material Expired - Lifetime US3194691A (en)

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3283220A (en) * 1962-07-24 1966-11-01 Ibm Mobility anisotropic semiconductor device
US3329884A (en) * 1964-06-08 1967-07-04 Bell Telephone Labor Inc Frequency multiplier utilizing a hybrid junction to provide isolation between the input and output terminals
US3342560A (en) * 1963-10-28 1967-09-19 Siemens Ag Apparatus for pulling semiconductor crystals
US3377182A (en) * 1963-03-27 1968-04-09 Siemens Ag Method of producing monocrystalline semiconductor bodies
US3655345A (en) * 1967-03-09 1972-04-11 Siemens Ag Method of growing rod-shaped dislocation-free monocrystals, particularly of silicon, by crucible-free floating zone melting
US3767473A (en) * 1970-12-11 1973-10-23 Philips Corp Method of manufacturing semiconductor single crystals
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
JPS4953372A (xx) * 1972-07-13 1974-05-23
US3880984A (en) * 1971-07-28 1975-04-29 Hitachi Ltd Method of producing plate single-crystal of gadolinium molybdate
US4894206A (en) * 1986-09-22 1990-01-16 Kabushiki Kaisha Toshiba Crystal pulling apparatus
FR2660940A1 (fr) * 1990-04-16 1991-10-18 Chichibu Cement Kk Procede de fabrication d'un monocristal de rutile.
US5069743A (en) * 1990-04-11 1991-12-03 Hughes Aircraft Company Orientation control of float-zone grown TiC crystals
US5492079A (en) * 1993-07-15 1996-02-20 Wacker-Chemitronic Gesellschaft Fur Elektronik-Grundstoffe Mbh Process for producing rods or blocks of semiconductor material and an apparatus for carrying out the process

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL171309C (nl) * 1970-03-02 1983-03-01 Hitachi Ltd Werkwijze voor de vervaardiging van een halfgeleiderlichaam, waarbij een laag van siliciumdioxyde wordt gevormd op een oppervlak van een monokristallijn lichaam van silicium.

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2651831A (en) * 1950-07-24 1953-09-15 Bell Telephone Labor Inc Semiconductor translating device
US2981875A (en) * 1957-10-07 1961-04-25 Motorola Inc Semiconductor device and method of making the same
US3018539A (en) * 1956-11-06 1962-01-30 Motorola Inc Diffused base transistor and method of making same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2651831A (en) * 1950-07-24 1953-09-15 Bell Telephone Labor Inc Semiconductor translating device
US3018539A (en) * 1956-11-06 1962-01-30 Motorola Inc Diffused base transistor and method of making same
US2981875A (en) * 1957-10-07 1961-04-25 Motorola Inc Semiconductor device and method of making the same

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3283220A (en) * 1962-07-24 1966-11-01 Ibm Mobility anisotropic semiconductor device
US3377182A (en) * 1963-03-27 1968-04-09 Siemens Ag Method of producing monocrystalline semiconductor bodies
US3342560A (en) * 1963-10-28 1967-09-19 Siemens Ag Apparatus for pulling semiconductor crystals
US3329884A (en) * 1964-06-08 1967-07-04 Bell Telephone Labor Inc Frequency multiplier utilizing a hybrid junction to provide isolation between the input and output terminals
US3655345A (en) * 1967-03-09 1972-04-11 Siemens Ag Method of growing rod-shaped dislocation-free monocrystals, particularly of silicon, by crucible-free floating zone melting
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
US3767473A (en) * 1970-12-11 1973-10-23 Philips Corp Method of manufacturing semiconductor single crystals
US3880984A (en) * 1971-07-28 1975-04-29 Hitachi Ltd Method of producing plate single-crystal of gadolinium molybdate
JPS4953372A (xx) * 1972-07-13 1974-05-23
US4894206A (en) * 1986-09-22 1990-01-16 Kabushiki Kaisha Toshiba Crystal pulling apparatus
US5069743A (en) * 1990-04-11 1991-12-03 Hughes Aircraft Company Orientation control of float-zone grown TiC crystals
FR2660940A1 (fr) * 1990-04-16 1991-10-18 Chichibu Cement Kk Procede de fabrication d'un monocristal de rutile.
US5492079A (en) * 1993-07-15 1996-02-20 Wacker-Chemitronic Gesellschaft Fur Elektronik-Grundstoffe Mbh Process for producing rods or blocks of semiconductor material and an apparatus for carrying out the process

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NL104644C (xx)
GB931992A (en) 1963-07-24
DE1256202B (de) 1967-12-14
NL243511A (xx)

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