JP2005298288A - Quartz crucible - Google Patents
Quartz crucible Download PDFInfo
- Publication number
- JP2005298288A JP2005298288A JP2004118451A JP2004118451A JP2005298288A JP 2005298288 A JP2005298288 A JP 2005298288A JP 2004118451 A JP2004118451 A JP 2004118451A JP 2004118451 A JP2004118451 A JP 2004118451A JP 2005298288 A JP2005298288 A JP 2005298288A
- Authority
- JP
- Japan
- Prior art keywords
- recess
- single crystal
- crucible
- quartz crucible
- silicon
- 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.)
- Granted
Links
- 239000010453 quartz Substances 0.000 title claims abstract description 59
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 59
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 123
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 123
- 239000010703 silicon Substances 0.000 claims abstract description 123
- 239000013078 crystal Substances 0.000 claims abstract description 77
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 5
- 239000010439 graphite Substances 0.000 claims abstract description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 52
- 229910052760 oxygen Inorganic materials 0.000 abstract description 52
- 239000001301 oxygen Substances 0.000 abstract description 52
- 239000007788 liquid Substances 0.000 abstract description 7
- 229920006395 saturated elastomer Polymers 0.000 description 10
- 230000007423 decrease Effects 0.000 description 9
- 238000009826 distribution Methods 0.000 description 9
- 239000000155 melt Substances 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 238000010438 heat treatment Methods 0.000 description 5
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 230000002093 peripheral effect Effects 0.000 description 4
- 229910052785 arsenic Inorganic materials 0.000 description 3
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 229910052787 antimony Inorganic materials 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005247 gettering Methods 0.000 description 2
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- 229920002472 Starch Polymers 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 150000002927 oxygen compounds Chemical class 0.000 description 1
- 150000003376 silicon Chemical class 0.000 description 1
- 235000019698 starch Nutrition 0.000 description 1
- 239000008107 starch Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Classifications
-
- 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
- Y02P40/57—Improving the yield, e-g- reduction of reject rates
Landscapes
- Glass Melting And Manufacturing (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Description
本発明は、チョクラルスキー法（以下、ＣＺ法という。）によりシリコン単結晶を引上げる装置に用いられ、そのシリコン単結晶を引上げるためのシリコン融液が貯留される石英ルツボに関するものである。 The present invention relates to a quartz crucible used in an apparatus for pulling up a silicon single crystal by the Czochralski method (hereinafter referred to as CZ method) and storing a silicon melt for pulling up the silicon single crystal. .
シリコン単結晶を育成する方法の一つとしてＣＺ法が用いられている。このＣＺ法は、先ず、多結晶シリコン原料を石英ルツボ内でシリコンの融点以上に加熱融解してシリコン融液とする。次いでこの石英ルツボに貯えられたシリコン融液に種結晶を浸す。種結晶が浸されその一部を融解した後に引上げを開始する。引上げ中、最初にネックと呼ばれる細い結晶部がインゴットへの転位成長を除くために育成される。次いでインゴットはネックから成長しその結晶径が徐々に増大する。最初にコーン部、続いて肩部が形成された後、一定の直径を有する直胴部が形成される。上記ステップを経ることにより円柱状のシリコン単結晶が育成される。 The CZ method is used as one method for growing a silicon single crystal. In this CZ method, first, a polycrystalline silicon raw material is heated and melted in a quartz crucible above the melting point of silicon to obtain a silicon melt. Next, the seed crystal is immersed in the silicon melt stored in the quartz crucible. Pulling is started after the seed crystal is immersed and a part thereof is melted. During pulling, a thin crystal part called a neck is first grown to eliminate dislocation growth into the ingot. The ingot then grows from the neck and its crystal diameter gradually increases. After the cone portion and then the shoulder portion are formed first, a straight body portion having a constant diameter is formed. A cylindrical silicon single crystal is grown through the above steps.
ＣＺ法における結晶成長の間、石英ルツボの内壁部はシリコン融液に接し、そして次の式（１）に示す反応の結果、徐々に溶解する。
ＳｉＯ2 ＋ Ｓｉ → ２ＳｉＯ ………… （１）
シリコン融液に混入したＳｉＯの大半は、シリコン融液の自由表面からＳｉＯガスとして蒸発するが、一部がシリコン単結晶とシリコン融液の界面である固液界面からシリコン単結晶に取り込まれ不純物酸素の源となる。シリコン単結晶の引上げ初期段階では、シリコン融液と石英ルツボ内壁部が接触する面積が比較的広いため、シリコン融液に溶解する酸素濃度は非常に高い。しかし、結晶成長が進んで、シリコン単結晶が形成されるとシリコン融液の液面は下がり、シリコン融液と石英ルツボ内壁部の接触面積は引上げ初期段階と比べて小さくなる。融液とルツボの接触面積の減少は石英ルツボからシリコン融液に溶解する酸素量を減少させる。従って、十分に成長したシリコン単結晶は、その軸方向で不均一な酸素分布を示す。より詳しくは酸素濃度は、その測定が結晶のシード端部、結晶の中央部、又は結晶のテール端部でなされるかによって、変化する。
During crystal growth in the CZ method, the inner wall of the quartz crucible contacts the silicon melt and gradually dissolves as a result of the reaction shown in the following formula (1).
SiO 2 + Si → 2SiO (1)
Most of the SiO mixed into the silicon melt evaporates as SiO gas from the free surface of the silicon melt, but a part of it is taken into the silicon single crystal from the solid-liquid interface that is the interface between the silicon single crystal and the silicon melt. It becomes a source of oxygen. At the initial stage of pulling the silicon single crystal, the area where the silicon melt and the inner wall of the quartz crucible are in contact with each other is relatively large, so that the concentration of oxygen dissolved in the silicon melt is very high. However, as the crystal growth progresses and a silicon single crystal is formed, the liquid level of the silicon melt decreases, and the contact area between the silicon melt and the inner wall of the quartz crucible becomes smaller than the initial stage of pulling. The reduction of the contact area between the melt and the crucible reduces the amount of oxygen dissolved from the quartz crucible into the silicon melt. Therefore, a sufficiently grown silicon single crystal shows a non-uniform oxygen distribution in its axial direction. More specifically, the oxygen concentration varies depending on whether the measurement is made at the seed end of the crystal, the center of the crystal, or the tail end of the crystal.
一方、シリコン融液に高濃度のＡｓ、ＰやＳｂ等の元素をドープして得られるＮ型シリコン単結晶は、パワーディスクリート市場（power discrete market）で用いられるエピタキシャルウェーハ（以下、エピウェーハという。）の出発原料として好都合であり、その生産量は増加傾向にある。良好なエピウェーハ基板に求められる本質的な２つの特性はそのバルクの抵抗率とその内部ゲッタリング能力である。ウェーハの内部ゲッタリング能力はこの結晶内部に増大した固有の酸素濃度に密接に関係している。Ｎ型シリコン単結晶のバルクの抵抗率とこうしたＮ型シリコン単結晶の酸素濃度との間には直接の相関関係があることが知られている。特定の結晶の抵抗率が低くなればなるほど、結晶構造に自然に取り入れられる酸素濃度は低くなる。この挙動の理由の一部は、ＡｓやＳｂのような元素が酸素化合物を形成しながら容易に融液表面から蒸発して融液中の酸素濃度を減少させることにある。例えば、融液中のＳｂは酸素と結合して酸素の溶解度を高め、一方で、Ｓｂ単体やＳｂ2Ｏ等の形で蒸発する。その結果、Ｓｂが高濃度で含まれると、溶液中では酸素濃度が減少し、Ｓｂを高度にドープした結晶中に高度に酸素を取り込むことが難しくなる。このように、低抵抗率と高酸素濃度を同時に満たすＮ型シリコン単結晶を得ることが困難であった。 On the other hand, an N-type silicon single crystal obtained by doping a silicon melt with an element such as As, P, or Sb at a high concentration is an epitaxial wafer (hereinafter referred to as an epi wafer) used in the power discrete market. It is convenient as a starting material for the above, and its production amount tends to increase. Two essential properties required for a good epi-wafer substrate are its bulk resistivity and its internal gettering ability. The internal gettering capability of the wafer is closely related to the increased intrinsic oxygen concentration inside the crystal. It is known that there is a direct correlation between the bulk resistivity of an N-type silicon single crystal and the oxygen concentration of such an N-type silicon single crystal. The lower the resistivity of a particular crystal, the lower the oxygen concentration that is naturally incorporated into the crystal structure. Part of the reason for this behavior is that elements such as As and Sb readily evaporate from the melt surface while forming oxygen compounds, thereby reducing the oxygen concentration in the melt. For example, Sb in the melt is combined with oxygen to increase the solubility of oxygen, while evaporating in the form of Sb alone or Sb 2 O. As a result, when Sb is contained in a high concentration, the oxygen concentration in the solution decreases, and it becomes difficult to incorporate oxygen into the crystal highly doped with Sb. Thus, it has been difficult to obtain an N-type silicon single crystal that simultaneously satisfies a low resistivity and a high oxygen concentration.
この点を解消するために、図１０に示すように、グラファイトサセプタ１により支持されて設けられた石英ルツボ３の内部に石英からなるリング部材４を挿入し、ヒータ７により加熱されたシリコン融液６をそのルツボ３に貯留し、そのシリコン融液６からシリコン単結晶２を引上げることが提案されている（例えば、特許文献１参照。）。これは、石英からなるリング部材４をシリコン融液６に浸漬させることにより、シリコン単結晶２の成長が進んでシリコン融液６の液面が下がった場合においても、そのリング部材４からシリコン融液６中に酸素を溶解させ、軸方向で均一な酸素分布を有するシリコン単結晶２を得ることができるものとしている。
しかし、石英からなるリング部材４をシリコン融液６に浸漬させると、そのリング部材４はルツボ３の内底部に設置されシリコン融液６中にルツボ３の内底面から突出するような形となる。そして、このリング部材４からシリコン融液６中に融解する酸素の量はその温度に比例するけれども、ルツボ３の上昇に伴いヒータ７による加熱量が変化し、リング部材４からシリコン融液６中に融解する酸素の量も変化し、シリコン融液６中に酸素を均一に融解させることが困難であるという未だ解決すべき課題が残存していた。
本発明の目的は、シリコン単結晶引き上げ中のシリコン融液中に酸素を均一に融解させることのできるシリコン単結晶の引上げ装置における石英ルツボを提供することにある。
However, when the ring member 4 made of quartz is immersed in the silicon melt 6, the ring member 4 is installed at the inner bottom portion of the crucible 3, and is shaped to protrude from the inner bottom surface of the crucible 3 into the silicon melt 6. . The amount of oxygen melted from the ring member 4 into the silicon melt 6 is proportional to the temperature, but the amount of heating by the heater 7 changes as the crucible 3 rises, and the ring member 4 into the silicon melt 6 changes. The amount of oxygen to be melted also changed, and there still remained a problem to be solved that it was difficult to uniformly melt oxygen in the silicon melt 6.
An object of the present invention is to provide a quartz crucible in a silicon single crystal pulling apparatus capable of uniformly melting oxygen in a silicon melt being pulled.
請求項１に係る発明は、図４に示すように、チャンバ１１内にグラファイトサセプタ１４により支持されて設けられシリコン単結晶２４を引上げるためのシリコン融液１２が貯留される石英ルツボ１３の改良である。
その特徴ある構成は、図１に示すように、内底部にシリコン融液１２が澱む凹み１３ａが形成されたところにある。
この請求項１に記載された石英ルツボ１３では、凹み１３ａに澱むシリコン融液１２は特に加熱されて多くの酸素が溶け出すため、その酸素濃度は飽和状態となる。一方、図３に示すように、ルツボ１３に貯留されたシリコン融液１２にはテイラープラウドマン（Taylor-Proudman）循環流Ｐが発生し、凹み１３ａに澱みシリコン融液１２はこの循環流Ｐにより上昇してシリコン単結晶２４に取り込まれる。即ち、シリコン単結晶２４の直胴部を形成する時に、酸素濃度の比較的高いシリコン融液１２が凹み１３ａから循環流Ｐにより上昇してその単結晶２４に取り込まれ、酸素濃度の低下を抑制する効果が得られる。
As shown in FIG. 4, the invention according to claim 1 is an improvement of a quartz crucible 13 provided in a chamber 11 by being supported by a graphite susceptor 14 and storing a silicon melt 12 for pulling up a silicon single crystal 24. It is.
As shown in FIG. 1, the characteristic configuration is that a recess 13a in which the silicon melt 12 is stagnation is formed in the inner bottom portion.
In the quartz crucible 13 described in claim 1, since the silicon melt 12 stagnating in the recess 13a is particularly heated and a large amount of oxygen is dissolved, the oxygen concentration becomes saturated. On the other hand, as shown in FIG. 3, a Taylor-Proudman circulation flow P is generated in the silicon melt 12 stored in the crucible 13, and the stagnation silicon melt 12 flows into the recess 13 a due to the circulation flow P. It rises and is taken into the silicon single crystal 24. That is, when the straight body portion of the silicon single crystal 24 is formed, the silicon melt 12 having a relatively high oxygen concentration rises from the recess 13a by the circulating flow P and is taken into the single crystal 24, thereby suppressing the decrease in the oxygen concentration. Effect is obtained.
請求項２に係る発明は、請求項１に係る発明であって、凹みがルツボ回転中心Ａを中心とする１又は２以上のリング状の溝１３ａであることを特徴とする。
請求項３に係る発明は、請求項１に係る発明であって、図９に示すように、凹みが複数の有底穴１３ｅであって、複数の有底穴１３ｅがルツボ回転中心Ａを中心とする同心円状に配列されたことを特徴とする。
この請求項２又は請求項３に記載された石英ルツボでは、凹みがリング状の溝１３ａ又は複数の有底穴１３ｅであるのでその加工が容易で、比較的安価に本発明の石英ルツボを得ることができる。
The invention according to claim 2 is the invention according to claim 1, characterized in that the recess is one or more ring-shaped grooves 13 a centering on the crucible rotation center A.
The invention according to claim 3 is the invention according to claim 1, wherein, as shown in FIG. 9, the recess is a plurality of bottomed holes 13e, and the plurality of bottomed holes 13e are centered on the crucible rotation center A. It is characterized by being arranged in a concentric circle.
In the quartz crucible described in claim 2 or claim 3, since the recess is the ring-shaped groove 13a or the plurality of bottomed holes 13e, the processing is easy, and the quartz crucible of the present invention is obtained at a relatively low cost. be able to.
請求項４に係る発明は、請求項１に係る発明であって、図６に示すように、内底部にルツボ回転中心Ａを中心としかつ互いに所定の間隔を開けてそれぞれリング状の一対の凸条１３ｂ，１３ｃが形成され、凹みが一対の凸条１３ｂ，１３ｃの間に形成されたリング状の溝１３ｄであることを特徴とする。
この請求項４に記載された石英ルツボでは、シリコン単結晶２４の直胴部を形成する時に、酸素濃度の比較的高いシリコン融液１２を凹み１３ｄから単結晶２４に取り込ませるとともに、その一対の凸条１３ｂ，１３ｃからもシリコン融液１２中に酸素を溶解させることができ、軸方向で均一な酸素分布を有するシリコン単結晶２４を得ることが可能になる。
The invention according to claim 4 is the invention according to claim 1, wherein, as shown in FIG. 6, a pair of ring-shaped projections, each centering on the crucible rotation center A and spaced apart from each other at the inner bottom portion, are provided. Strips 13b and 13c are formed, and the recess is a ring-shaped groove 13d formed between the pair of projections 13b and 13c.
In the quartz crucible described in claim 4, when forming the straight body portion of the silicon single crystal 24, the silicon melt 12 having a relatively high oxygen concentration is taken into the single crystal 24 from the recess 13d, and the pair of Oxygen can be dissolved in the silicon melt 12 also from the ridges 13b and 13c, and a silicon single crystal 24 having a uniform oxygen distribution in the axial direction can be obtained.
請求項５に係る発明は、請求項１ないし４いずれか１項に係る発明であって、図１、図６及び図９に示すように、凹み１３ａ，１３ｄ．１３ｅは凹み開口部Ｂが凹み内部Ｃより小さくなるように形成されたことを特徴とする。
この請求項５に記載された石英ルツボでは、凹み開口部Ｂが凹み内部Ｃより小さくなるように形成するので、酸素濃度が飽和状態の凹み１３ａに澱みシリコン融液１２を循環流Ｐより徐々に上昇させてシリコン単結晶２４に取り込ませることができ、シリコン単結晶２４の直胴部を形成する時の酸素濃度の低下を有効に抑制することができる。
The invention according to a fifth aspect is the invention according to any one of the first to fourth aspects, wherein the recesses 13a, 13d,. 13e is characterized in that the dent opening B is formed to be smaller than the dent inside C.
In the quartz crucible described in claim 5, the recess opening B is formed so as to be smaller than the recess C. Therefore, the silicon melt 12 is gradually added to the recess 13 a in which the oxygen concentration is saturated from the circulating flow P. The silicon single crystal 24 can be raised and taken in, and the decrease in oxygen concentration when the straight body portion of the silicon single crystal 24 is formed can be effectively suppressed.
請求項６に係る発明は、請求項１ないし５いずれか１項に係る発明であって、凹み１３ａ，１３ｄ．１３ｅが引き上げられるシリコン単結晶２４の直径Ｄに相当する径の範囲内で内底部に形成されたことを特徴とする。
この請求項６に記載された石英ルツボでは、酸素濃度が飽和状態となる凹み１３ａ，１３ｄ．１３ｅ内部のシリコン融液１２を循環流Ｐに乗せてシリコン単結晶２４に有効に取り込ませることができ、酸素濃度の低下を更に有効に抑制することができる。
The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the recesses 13a, 13d. 13e is formed on the inner bottom within a diameter range corresponding to the diameter D of the silicon single crystal 24 to be pulled up.
In the quartz crucible described in claim 6, the recesses 13a, 13d. The silicon melt 12 inside 13e can be put on the circulating flow P and effectively taken into the silicon single crystal 24, and the decrease in oxygen concentration can be further effectively suppressed.
本発明の石英ルツボでは、内底部にシリコン融液が澱む凹みを形成したので、凹みに澱むシリコン融液は特に加熱されて多くの酸素が溶け出してその酸素濃度は飽和状態となり、酸素濃度が飽和状態のシリコン融液はテイラープラウドマン循環流により上昇してシリコン単結晶に取り込まれる。従って、シリコン単結晶の直胴部を形成する時に、酸素濃度の比較的高いシリコン融液をその凹みから単結晶に取り込ませて酸素濃度の低下を抑制することができる。この場合の凹みは、ルツボ回転中心Ａを中心とする１又は２以上のリング状の溝であったり、複数の有底穴であってルツボ回転中心を中心とする同心円状に配列されたものであることが好ましい。或いは、内底部にルツボ回転中心を中心としかつ互いに所定の間隔を開けてそれぞれリング状の一対の凸条を形成し、この一対の凸条の間を凹みとしても良い。 In the quartz crucible of the present invention, a recess in which the silicon melt stagnates was formed in the inner bottom, so that the silicon melt stagnated in the recess was heated particularly so that a large amount of oxygen was dissolved and the oxygen concentration became saturated, and the oxygen concentration was The saturated silicon melt is raised by the Taylor Proudman circulating flow and taken into the silicon single crystal. Therefore, when forming the straight body portion of the silicon single crystal, a silicon melt having a relatively high oxygen concentration can be taken into the single crystal from the recess to suppress a decrease in the oxygen concentration. The dents in this case are one or more ring-shaped grooves centered on the crucible rotation center A, or a plurality of bottomed holes arranged concentrically around the crucible rotation center. Preferably there is. Alternatively, a pair of ring-shaped ridges may be formed on the inner bottom portion with the crucible rotation center as a center and a predetermined distance from each other, and a recess may be formed between the pair of ridges.
また、凹みは凹み開口部が凹み内部より小さくなるように形成すれば、酸素濃度が飽和状態の凹みに澱みシリコン融液をその循環流より徐々に上昇させてシリコン単結晶に取り込ませることができ、凹みが引き上げられるシリコン単結晶の直径に相当する径の範囲内に形成すれば、酸素濃度が飽和状態となる凹み内部のシリコン融液をその循環流に乗せてシリコン単結晶に有効に取り込ませることができる。 In addition, if the dent is formed so that the opening of the dent is smaller than the inside of the dent, the silicon melt can gradually rise from the circulating flow into the dent in which the oxygen concentration is saturated and can be taken into the silicon single crystal. If the dent is formed within the diameter range corresponding to the diameter of the silicon single crystal to be pulled up, the silicon melt inside the dent where the oxygen concentration is saturated is put on the circulating flow and effectively taken into the silicon single crystal. be able to.
次に本発明を実施するための最良の形態を図面に基づいて説明する。
図４に示すように、シリコン単結晶引上げ装置１０のチャンバ１１内には、シリコン融液１２を貯える石英ルツボ１３が設けられ、この石英ルツボ１３はグラファイトサセプタ１４により外周面及び外底面を包囲されて支持される。サセプタ１４は支軸１６の上端に固定され、この支軸１６の下部はルツボ駆動手段１７に接続される。ルツボ駆動手段１７は図示しないが石英ルツボ１３を回転させる第１回転用モータと、石英ルツボ１３を昇降させる昇降用モータとを有し、これらのモータにより石英ルツボ１３が所定の方向に回転し、かつ上下方向に移動できるようになっている。サセプタ１４の外周面はヒータ１８により包囲され、このヒータ１８は保温筒１９により包囲される。ヒータ１８は石英ルツボ１３に充填された高純度の多結晶シリコン原料を加熱融解してシリコン融液１２にする。
Next, the best mode for carrying out the present invention will be described with reference to the drawings.
As shown in FIG. 4, a quartz crucible 13 for storing a silicon melt 12 is provided in the chamber 11 of the silicon single crystal pulling apparatus 10, and this quartz crucible 13 is surrounded by a graphite susceptor 14 on the outer peripheral surface and the outer bottom surface. Supported. The susceptor 14 is fixed to the upper end of the support shaft 16, and the lower portion of the support shaft 16 is connected to the crucible driving means 17. Although not shown, the crucible driving means 17 has a first rotation motor that rotates the quartz crucible 13 and a lifting motor that raises and lowers the quartz crucible 13, and the quartz crucible 13 is rotated in a predetermined direction by these motors. And it can move up and down. The outer peripheral surface of the susceptor 14 is surrounded by a heater 18, and the heater 18 is surrounded by a heat insulating cylinder 19. The heater 18 heats and melts the high-purity polycrystalline silicon raw material filled in the quartz crucible 13 to form the silicon melt 12.
またチャンバ１１の上端の円筒状のケーシング２１には引上げ手段２２が設けられる。引上げ手段２２はケーシング２１の上端部に水平状態で旋回可能に設けられた引上げヘッド（図示せず）と、このヘッドを回転させる第２回転用モータ（図示せず）と、ヘッドから石英ルツボ１３の回転中心に向って垂下されたワイヤケーブル２３と、上記ヘッド内に設けられワイヤケーブル２３を巻取り又は繰出す引上げ用モータ（図示せず）とを有する。ワイヤケーブル２３の下端には種結晶２６が取付けられる。シリコン単結晶２４の外周面と保温筒１９の内周面との間にはシリコン単結晶２４を包囲する円筒状の熱遮断部材２７が設けられる。この熱遮断部材２７はコーン部２７ａとフランジ部２７ｂからなり、このフランジ部２７ｂを保温筒１９に取付けることにより熱遮蔽部材２７が固定される。 A pulling means 22 is provided in a cylindrical casing 21 at the upper end of the chamber 11. The pulling means 22 is a pulling head (not shown) provided at the upper end of the casing 21 so as to be turnable in a horizontal state, a second rotating motor (not shown) for rotating the head, and the quartz crucible 13 from the head. And a pulling motor (not shown) that is provided in the head and winds or feeds the wire cable 23. A seed crystal 26 is attached to the lower end of the wire cable 23. A cylindrical heat blocking member 27 is provided between the outer peripheral surface of the silicon single crystal 24 and the inner peripheral surface of the heat retaining cylinder 19 to surround the silicon single crystal 24. The heat shield member 27 includes a cone portion 27a and a flange portion 27b, and the heat shield member 27 is fixed by attaching the flange portion 27b to the heat retaining cylinder 19.
この第１の実施の形態の特徴ある構成は、図１及ぶ図５に示すように、ルツボ１３の内底部にシリコン融液１２が澱む凹み１２ａが形成されたところにある。この実施の形態における凹み１３ａは、図１に詳しく示すように、ルツボ駆動手段１７によりそのルツボ１３が回転するルツボ回転中心Ａを中心としてルツボ１３の内底部に形成されたリング状の溝である。そしてこの凹み１３ａは、図１の拡大図に示すように、凹み開口部Ｂが凹み内部Ｃより小さくなるように形成され、引き上げられるシリコン単結晶の直径Ｄに相当する径の範囲内で内底部に形成される。 The characteristic configuration of the first embodiment is that a recess 12a in which the silicon melt 12 stagnates is formed at the inner bottom of the crucible 13, as shown in FIGS. As shown in detail in FIG. 1, the recess 13 a in this embodiment is a ring-shaped groove formed in the inner bottom portion of the crucible 13 around the crucible rotation center A around which the crucible 13 rotates by the crucible driving means 17. . As shown in the enlarged view of FIG. 1, the recess 13a is formed so that the recess opening B is smaller than the recess C, and the inner bottom portion is within a range corresponding to the diameter D of the silicon single crystal to be pulled up. Formed.
このような構成のルツボを用いたシリコン単結晶の引上げ方法について説明する。
先ず高純度の多結晶シリコン原料を石英ルツボ１３に充填し、ヒータ１８でシリコンの融点以上に加熱融解してシリコン融液１２にする。次いで石英ルツボ１３に貯えられたシリコン融液１２に種結晶２６を浸し、種結晶２６そのものを融解した後にルツボ駆動手段１７によりそのルツボ１３を回転させ、その状態でワイヤケーブル２３を回転させながら引上げることにより円柱状のシリコン単結晶２４を育成する。このとき石英ルツボ１３はワイヤケーブル２３の回転と逆の回転をさせる。
A method for pulling a silicon single crystal using the crucible having such a structure will be described.
First, a high-purity polycrystalline silicon raw material is filled in a quartz crucible 13, and heated and melted to a melting point of silicon or higher by a heater 18 to obtain a silicon melt 12. Next, the seed crystal 26 is immersed in the silicon melt 12 stored in the quartz crucible 13, and after melting the seed crystal 26 itself, the crucible driving means 17 rotates the crucible 13, and the wire cable 23 is rotated while being pulled. The cylindrical silicon single crystal 24 is grown by raising. At this time, the quartz crucible 13 rotates in the direction opposite to the rotation of the wire cable 23.
融液１２が形成されるとき及び単結晶２４の直胴部が形成されるときに行うヒータ１８による加熱は、先ず石英ルツボ１３の温度がその加熱により上昇しその後シリコン融液１２に伝達される。このときの温度分布状態を図２に示す。図２から明らかなように、石英ルツボ１３がヒータ１８により先ず加熱されることから、その加熱された石英ルツボ１３の内底部に形成された凹み１３ａに澱むシリコン融液１２は特に加熱されて多くの酸素が溶け出すため、その酸素濃度は飽和状態となる。 When the melt 12 is formed and when the straight body portion of the single crystal 24 is formed, the heating by the heater 18 first increases the temperature of the quartz crucible 13 by the heating, and then is transmitted to the silicon melt 12. . The temperature distribution state at this time is shown in FIG. As apparent from FIG. 2, the quartz crucible 13 is first heated by the heater 18, so that the silicon melt 12 stagnating in the recess 13a formed in the inner bottom portion of the heated quartz crucible 13 is heated particularly much. The oxygen concentration is saturated, so that the oxygen concentration is saturated.
一方、図３に示すように、ルツボ１３に貯留されたシリコン融液１２にはシリコン単結晶２４とルツボ１３が回転することから生じるテイラープラウドマン循環流Ｐ（以下、「循環流Ｐ」という。）が発生する。この循環流Ｐはシリコン単結晶２４の直径に相当するルツボ底部から上昇してルツボ１３の中央底部に向かって下降する対流である。一方、この循環流Ｐの外側におけるルツボ１３の周囲では、その内周部分から上昇しシリコン単結晶２４の径に相当する部分から下降する対流Ｇも生じる。従って、凹み１３ａに澱み酸素濃度が飽和状態にあるシリコン融液１２は循環流Ｐより上昇してシリコン単結晶２４に取り込まれることになる。即ち、シリコン単結晶２４の直胴部を形成する時に、酸素濃度の比較的高いシリコン融液１２が凹み１３ａから循環流Ｐにより上昇してその単結晶２４に取り込まれ、酸素濃度の低下を抑制する効果が得られる。このルツボ１３を用いて形成したシリコン単結晶２４は、従来の方法の課題であったシード端部、直胴部及びテール端部それぞれの位置によって含まれる酸素濃度の不均一な分布を解消することができる。よって、ＡｓやＳｂでドープされたシリコン融液１２の酸素濃度の低下も抑制することができる。 On the other hand, as shown in FIG. 3, the Taylor-Plaudeman circulation flow P (hereinafter referred to as “circulation flow P”) generated from the rotation of the silicon single crystal 24 and the crucible 13 in the silicon melt 12 stored in the crucible 13. ) Occurs. This circulating flow P is a convection that rises from the bottom of the crucible corresponding to the diameter of the silicon single crystal 24 and descends toward the center bottom of the crucible 13. On the other hand, around the crucible 13 outside the circulating flow P, a convection G that rises from the inner circumferential portion and descends from a portion corresponding to the diameter of the silicon single crystal 24 also occurs. Accordingly, the silicon melt 12 in which the starch oxygen concentration is saturated in the recess 13 a rises from the circulating flow P and is taken into the silicon single crystal 24. That is, when the straight body portion of the silicon single crystal 24 is formed, the silicon melt 12 having a relatively high oxygen concentration rises from the recess 13a by the circulating flow P and is taken into the single crystal 24, thereby suppressing the decrease in the oxygen concentration. Effect is obtained. The silicon single crystal 24 formed using this crucible 13 eliminates the uneven distribution of the oxygen concentration contained depending on the positions of the seed end, the straight body, and the tail end, which was a problem of the conventional method. Can do. Therefore, a decrease in oxygen concentration of the silicon melt 12 doped with As or Sb can also be suppressed.
図６に本発明の第２の実施の形態を示す。図面中上述した実施の形態と同一符号は同一部品を示し、繰り返しての説明を省略する。
この第２の実施の形態の特徴ある構成は、図６に示すように、内底部にルツボ回転中心Ａを中心としかつ互いに所定の間隔を開けてそれぞれリング状の一対の凸条１３ｂ、１３ｃが形成されたところにある。そして、一対の凸条１３ｂ，１３ｃの間に形成されたリング状の溝が、シリコン融液１２が澱む凹み１３ｄを形成する。そしてこの凹み１３ｄは、図７及び図８に示すように、凹み開口部Ｂが凹み内部Ｃより小さくなるように形成され、引き上げられるシリコン単結晶の直径Ｄに相当する径の範囲内で内底部に形成される。
FIG. 6 shows a second embodiment of the present invention. In the drawings, the same reference numerals as those in the above-described embodiment denote the same parts, and repeated description will be omitted.
As shown in FIG. 6, the characteristic configuration of the second embodiment is that a pair of ring-shaped ridges 13b and 13c are formed at the inner bottom centered on the crucible rotation center A and spaced apart from each other. It is where it was formed. The ring-shaped groove formed between the pair of ridges 13b and 13c forms a recess 13d in which the silicon melt 12 is stagnated. As shown in FIGS. 7 and 8, the recess 13d is formed so that the recess opening B is smaller than the recess C, and the inner bottom portion is within a range corresponding to the diameter D of the silicon single crystal to be pulled up. Formed.
このような構成の石英ルツボ１３では、融液１２が形成されるとき及び単結晶２４の直胴部が形成されるときに行うヒータ１８による加熱は、先ず石英ルツボ１３の温度がその加熱により上昇しその後シリコン融液１２に伝達される。このときの温度分布状態を示す図７から、石英ルツボ１３はヒータ１８により先ず加熱され、その加熱された石英ルツボ１３の内底部に形成された一対の凸条１３ｂ，１３ｃが加熱される。従って、一対の凸条１３ｂ，１３ｃの間に形成された凹み１３ｄに澱むシリコン融液１２は特に加熱されて多くの酸素が溶け出すため、その酸素濃度は飽和状態となる。 In the quartz crucible 13 having such a configuration, when the melt 12 is formed and when the straight body portion of the single crystal 24 is formed, the heating by the heater 18 first increases the temperature of the quartz crucible 13 by the heating. Then, it is transmitted to the silicon melt 12. From FIG. 7 showing the temperature distribution state at this time, the quartz crucible 13 is first heated by the heater 18, and the pair of ridges 13 b and 13 c formed on the inner bottom portion of the heated quartz crucible 13 is heated. Accordingly, the silicon melt 12 stagnating in the recess 13d formed between the pair of ridges 13b and 13c is particularly heated to dissolve a large amount of oxygen, so that the oxygen concentration is saturated.
一方、図８に示すように、ルツボ１３に貯留されたシリコン融液１２にはシリコン単結晶２４とルツボ１３が回転することから生じる循環流Ｐが発生する。従って、凹み１３ｄに澱み酸素濃度が飽和状態にあるシリコン融液１２は循環流Ｐより上昇してシリコン単結晶２４に取り込まれ、酸素濃度の低下を抑制する。そして一対の凸条１３ｂ，１３ｃはシリコン融液１２中に突出するように形成されるため、一対の凸条１３ｂ，１３ｃからもシリコン融液１２中に酸素を溶解させることができ、軸方向で均一な酸素分布を有するシリコン単結晶２４を得ることが可能になる。 On the other hand, as shown in FIG. 8, the silicon melt 12 stored in the crucible 13 generates a circulating flow P resulting from the rotation of the silicon single crystal 24 and the crucible 13. Accordingly, the silicon melt 12 in which the stagnation oxygen concentration is saturated in the recess 13d rises from the circulating flow P and is taken into the silicon single crystal 24, thereby suppressing the decrease in the oxygen concentration. And since a pair of protruding item | line 13b, 13c is formed so that it may protrude in the silicon melt 12, oxygen can be melt | dissolved in the silicon melt 12 also from a pair of protruding item | line 13b, 13c, and it is an axial direction. It is possible to obtain the silicon single crystal 24 having a uniform oxygen distribution.
なお、上述した実施の形態では、リング状の溝１３ａからなる凹み、及び一対の凸条１３ｂ，１３ｃの間に形成されたリング状の溝１３ｄからなる凹みを説明したが、図９に示すように、凹みは複数の有底穴１３ｅであっても良い。この場合の複数の有底穴１３ｅは、酸素濃度の比較的高いシリコン融液１２を凹み１３ｅから単結晶２４に均一に取り込ませるため、ルツボ回転中心Ａを中心とする同心円状に配列することが好ましい。 In the above-described embodiment, the dent composed of the ring-shaped groove 13a and the dent composed of the ring-shaped groove 13d formed between the pair of ridges 13b and 13c have been described. However, as shown in FIG. In addition, the recess may be a plurality of bottomed holes 13e. In this case, the plurality of bottomed holes 13e can be arranged concentrically around the crucible rotation center A in order to allow the silicon melt 12 having a relatively high oxygen concentration to be uniformly taken into the single crystal 24 from the recess 13e. preferable.
１１ チャンバ
１２ シリコン融液
１３ 石英ルツボ
１３ａ 溝（凹み）
１３ｂ，１３ｃ 凸条
１３ｄ 溝（凹み）
１３ｅ 有底穴（凹み）
１４ サセプタ
２４ シリコン単結晶
Ａ ルツボ回転中心
Ｂ 凹み開口部
Ｃ 凹み内部
Ｄ シリコン単結晶の直径
11 Chamber 12 Silicon melt 13 Quartz crucible 13a Groove (dent)
13b, 13c ridge 13d groove (dent)
13e Bottomed hole (dent)
14 susceptor 24 silicon single crystal A crucible rotation center B dent opening C dent inside D silicon single crystal diameter
Claims (6)
内底部に前記シリコン融液(12)が澱む凹み(13a,13d.13e)が形成されたことを特徴とする石英ルツボ。 In the quartz crucible (13) in which the silicon melt (12) for pulling up the silicon single crystal (24) provided to be supported by the graphite susceptor (14) is stored in the chamber (11).
A quartz crucible characterized in that a recess (13a, 13d.13e) in which the silicon melt (12) stagnates is formed in an inner bottom portion.
The quartz crucible according to any one of claims 1 to 5, wherein the recess (13a, 13d.13e) is formed on the inner bottom within a diameter range corresponding to the diameter (D) of the silicon single crystal (24) to be pulled up. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004118451A JP4466175B2 (en) | 2004-04-14 | 2004-04-14 | Quartz crucible |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004118451A JP4466175B2 (en) | 2004-04-14 | 2004-04-14 | Quartz crucible |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2005298288A true JP2005298288A (en) | 2005-10-27 |
| JP4466175B2 JP4466175B2 (en) | 2010-05-26 |
Family
ID=35330289
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004118451A Expired - Lifetime JP4466175B2 (en) | 2004-04-14 | 2004-04-14 | Quartz crucible |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4466175B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008095594A1 (en) * | 2007-01-19 | 2008-08-14 | Vesuvius Crucible Company | Crucible and method of filling a crucible for melting a non-ferrous product |
| EP2071059A1 (en) * | 2007-12-14 | 2009-06-17 | Japan Super Quartz Corporation | High-purity vitreous silica crucible for pulling large-diameter single-crystal silicon ingot |
| EP2687623A1 (en) * | 2011-12-12 | 2014-01-22 | Shin-Etsu Quartz Products Co., Ltd. | Silica container for pulling up single crystal silicon, and method for manufacturing same |
| WO2019116972A1 (en) * | 2017-12-12 | 2019-06-20 | 信越石英株式会社 | Mold and method for manufacturing quartz glass crucible |
| CN114347218A (en) * | 2021-12-28 | 2022-04-15 | 宁夏盾源聚芯半导体科技股份有限公司 | Preparation device and method of quartz crucible for improving tail oxygen content of czochralski single crystal silicon rod and quartz crucible |
-
2004
- 2004-04-14 JP JP2004118451A patent/JP4466175B2/en not_active Expired - Lifetime
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008095594A1 (en) * | 2007-01-19 | 2008-08-14 | Vesuvius Crucible Company | Crucible and method of filling a crucible for melting a non-ferrous product |
| EP2071059A1 (en) * | 2007-12-14 | 2009-06-17 | Japan Super Quartz Corporation | High-purity vitreous silica crucible for pulling large-diameter single-crystal silicon ingot |
| KR101104674B1 (en) | 2007-12-14 | 2012-01-13 | 쟈판 스파 쿼츠 가부시키가이샤 | High-purity vitreous silica crucible used for pulling large-diameter single-crystal silicon ingot which enables reduction of pinhole defect among large-diameter single-crystal silicon ingot |
| US8172945B2 (en) | 2007-12-14 | 2012-05-08 | Japan Super Quartz Corporation | High-purity vitreous silica crucible for pulling large-diameter single-crystal silicon ingot |
| EP2687623A1 (en) * | 2011-12-12 | 2014-01-22 | Shin-Etsu Quartz Products Co., Ltd. | Silica container for pulling up single crystal silicon, and method for manufacturing same |
| EP2687623A4 (en) * | 2011-12-12 | 2015-01-07 | Shinetsu Quartz Prod | Silica container for pulling up single crystal silicon, and method for manufacturing same |
| US9382640B2 (en) | 2011-12-12 | 2016-07-05 | Shin-Etsu Quartz Products Co., Ltd. | Single crystal silicon pulling silica container and manufacturing method thereof |
| WO2019116972A1 (en) * | 2017-12-12 | 2019-06-20 | 信越石英株式会社 | Mold and method for manufacturing quartz glass crucible |
| JP2019104647A (en) * | 2017-12-12 | 2019-06-27 | 信越石英株式会社 | Mold and method for manufacturing quartz glass crucible |
| US11905196B2 (en) | 2017-12-12 | 2024-02-20 | Shin-Etsu Quartz Products Co., Ltd. | Mold and method for manufacturing quartz glass crucible |
| CN114347218A (en) * | 2021-12-28 | 2022-04-15 | 宁夏盾源聚芯半导体科技股份有限公司 | Preparation device and method of quartz crucible for improving tail oxygen content of czochralski single crystal silicon rod and quartz crucible |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4466175B2 (en) | 2010-05-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101105950B1 (en) | Manufacturing device for crystal ingot | |
| JP2008100854A (en) | Apparatus and method of manufacturing sic single crystal | |
| JP2755588B2 (en) | Crystal pulling method | |
| KR101048831B1 (en) | Graphite heater for producing single crystal, single crystal manufacturing device and single crystal manufacturing method | |
| CN107849728B (en) | System and method for low oxygen crystal growth using a two-layer continuous Czochralsk method | |
| JP3970580B2 (en) | Silicon single crystal pulling apparatus and pulling method thereof | |
| JP5399212B2 (en) | Method for producing silicon single crystal | |
| KR100679135B1 (en) | Thermal shield member of silicon single crystal pulling system | |
| JP2017222551A (en) | Production method of silicon single crystal | |
| JP2006315869A (en) | Method for manufacturing nitrogen-doped silicon single crystal | |
| JP4466175B2 (en) | Quartz crucible | |
| JP2813592B2 (en) | Single crystal manufacturing method | |
| JP2010254487A (en) | Method for growing single crystal | |
| JPH11130592A (en) | Production of silicon single crystal | |
| KR101218664B1 (en) | Semiconductor Single Crystal Ingot dopped by carbon and Method of manufacturing the same | |
| CN109154101B (en) | Method for producing single-crystal silicon semiconductor wafer, apparatus for producing single-crystal silicon semiconductor wafer, and single-crystal silicon semiconductor wafer | |
| JP4218460B2 (en) | Graphite heater for single crystal production, single crystal production apparatus and single crystal production method | |
| CN105887187B (en) | Method for stably controlling concentration of dopant for silicon single crystal growth | |
| KR100714215B1 (en) | High quality silicon single crystal ingot and high quality silicon wafer manufactured from the same | |
| JP4148060B2 (en) | Graphite heater for single crystal production, single crystal production apparatus and single crystal production method | |
| JP2006199533A (en) | Method for pulling silicon single crystal | |
| JP4148059B2 (en) | Graphite heater for single crystal production, single crystal production apparatus and single crystal production method | |
| KR101105526B1 (en) | Heater used for manufacturing single crystal ingot and single crystal ingot manufacturing apparatus having the same | |
| JP2017193469A (en) | After-heater and sapphire single crystal production apparatus | |
| KR100793371B1 (en) | Growing method of silicon single crystal and apparatus for growing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20060711 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20081017 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20081028 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20081203 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20091208 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20100108 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20100202 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20100215 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 4466175 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130305 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130305 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140305 Year of fee payment: 4 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |