JPH06321552A - Production of fluorine-doped quartz glass - Google Patents

Production of fluorine-doped quartz glass

Info

Publication number
JPH06321552A
JPH06321552A JP10857493A JP10857493A JPH06321552A JP H06321552 A JPH06321552 A JP H06321552A JP 10857493 A JP10857493 A JP 10857493A JP 10857493 A JP10857493 A JP 10857493A JP H06321552 A JPH06321552 A JP H06321552A
Authority
JP
Japan
Prior art keywords
fluorine
quartz glass
plasma
plasma flame
doped quartz
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
JP10857493A
Other languages
Japanese (ja)
Inventor
Kouji Tsumanuma
孝司 妻沼
Katsuyuki Seto
克之 瀬戸
Kazuo Sanada
和夫 真田
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.)
Fujikura Ltd
Original Assignee
Fujikura 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 Fujikura Ltd filed Critical Fujikura Ltd
Priority to JP10857493A priority Critical patent/JPH06321552A/en
Publication of JPH06321552A publication Critical patent/JPH06321552A/en
Pending legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/012—Manufacture of preforms for drawing fibres or filaments
    • C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
    • C03B37/01413—Reactant delivery systems
    • C03B37/0142—Reactant deposition burners
    • C03B37/01426—Plasma deposition burners or torches
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2201/00—Type of glass produced
    • C03B2201/06—Doped silica-based glasses
    • C03B2201/08—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant
    • C03B2201/12—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant doped with fluorine

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Plasma & Fusion (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Glass Melting And Manufacturing (AREA)
  • Manufacture, Treatment Of Glass Fibers (AREA)

Abstract

PURPOSE:To provide a process for the production of a fluorine-doped quartz glass having high specific refractive index difference at stable deposition rate. CONSTITUTION:A fluorine-doped quartz glass is formed on the circumference of a starting member 10 by plasma outer deposition method. The deposition process is carried out by placing a plasma torch opposite to the starting member 10 and perpendicular to the length of the member and supplying a quartz glass raw material gas coaxially with a plasma flame 11 ejected from the plasma torch simultaneously with the supply of a fluorine-based gas 15 into the plasma flame 11 from a direction different from the direction of the quarts glass raw material. Since the fluorine-based gas is supplied to the plasma flame 11 independent of the supply of the quartz glass raw material gas, the etching of the formed glass with the fluorine-based gas can be inhibited to attain a stable deposition rate.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、フッ素ドープ石英ガラ
スの製造方法に関する。FIELD OF THE INVENTION The present invention relates to a method for producing fluorine-doped quartz glass.

【０００２】[0002]

【従来の技術】一般に、光ファイバは、高屈折率のコア
と、その周囲に設けられた低屈折率のクラッドよりなる
が、その一例として、ゲルマニウムドープ石英ガラスを
コアとし、純粋石英ガラスをクラッドとしたもの、ある
いは純粋石英ガラスをコアとし、フッ素ドープ石英ガラ
スをクラッドとしたものなどがある。純粋石英ガラスを
コアとした光ファイバは、ゲルマニウムドープ石英ガラ
スをコアとした光ファイバに比べ、短波長側で低損失で
あることや、耐放射線特性に優れるなどの点から、その
需要が盛んである。2. Description of the Related Art Generally, an optical fiber comprises a high-refractive index core and a low-refractive index clad provided around the core. As an example thereof, germanium-doped silica glass is used as the core and pure silica glass is used as the cladding. Or a core made of pure quartz glass and a cladding made of fluorine-doped quartz glass. Optical fiber with a core of pure silica glass is in high demand because of its low loss on the short wavelength side and excellent radiation resistance compared to the optical fiber with a core of germanium-doped silica glass. is there.

【０００３】この純粋石英ガラスをコアとし、フッ素ド
ープ石英ガラスをクラッドとした光ファイバ母材を作製
する方法としては、ＣＶＤ（化学気相沈積）法、ＶＡＤ
（気相軸付け）法、プラズマ外付け法などが挙げられ
る。As a method for producing an optical fiber preform having this pure quartz glass as a core and fluorine-doped quartz glass as a clad, a CVD (Chemical Vapor Deposition) method, VAD is used.
(Vapor axis attachment) method, plasma external attachment method and the like.

【０００４】ところが、ＣＶＤ法は、石英管を出発母材
とするため、薄肉クラッドの母材が得難い。またＶＡＤ
法では、比屈折率差が０.７％程度が限界であるという
問題があり、特に紫外線透過用または耐放射線光ファイ
バやイメージファイバ用母材の作製には不適当である。However, in the CVD method, since a quartz tube is used as a starting base material, it is difficult to obtain a base material with a thin clad. Also VAD
The method has a problem that the relative refractive index difference is limited to about 0.7%, and is particularly unsuitable for producing a base material for transmitting ultraviolet light or for a radiation resistant optical fiber or an image fiber.

【０００５】一方、プラズマ炎によるプラズマ外付け法
は、比屈折率差が１.０程度と非常に大きな石英ガラス
を得ることができる。On the other hand, the plasma external attachment method using a plasma flame makes it possible to obtain quartz glass having a very large relative refractive index difference of about 1.0.

【０００６】従来のプラズマ外付け法によるフッ素ドー
プ石英ガラスの製造方法を図２に示す。図中符号１が出
発石英棒である。この出発石英棒１を回転させつつ左右
に移動させながら、一定方向（直交方向）からプラズマ
炎２を放射する。プラズマ炎２中には、これと同軸方向
から、原料ガスであるＳｉＣｌ4、Ｏ2とＳＦ6を同時に
供給する。FIG. 2 shows a conventional method for producing fluorine-doped quartz glass by a plasma external attachment method. Reference numeral 1 in the figure is a starting quartz rod. While the starting quartz rod 1 is rotated and moved left and right, the plasma flame 2 is emitted from a fixed direction (orthogonal direction). Raw material gases SiCl 4 , O 2 and SF 6 are simultaneously supplied into the plasma flame 2 in the same direction as the plasma flame 2.

【０００７】[0007]

【発明が解決しようとする課題】ところが、前記方法で
は、ディポジション速度が０.０５ｇ／ｍｉｎ程度と非
常に遅いことが問題であった。その理由としては、一般
にフッ素系ガスがエッチング作用を有するために、石英
ガラス原料ガスと同時にフッ素系ガスをプラズマ炎内に
供給すると、その供給量次第ではガラス生成とエッチン
グが相殺してガラスの成長が遅くなるということが考え
られる。However, the above-mentioned method has a problem that the deposition speed is very slow at about 0.05 g / min. The reason for this is that, since fluorine-based gas generally has an etching action, when fluorine-based gas is supplied into the plasma flame at the same time as the quartz glass raw material gas, glass generation and etching cancel out depending on the supply amount, and glass growth occurs. Can be slow.

【０００８】本発明は、このような事情に鑑みてなされ
たものであって、フッ素系ガスによる生成ガラスのエッ
チングを極力抑制してディポジション速度の低下防止を
図ったフッ素ドープ石英ガラスの製造方法を提供するこ
とを目的としている。The present invention has been made in view of the above circumstances, and is a method for producing a fluorine-doped quartz glass in which the etching of the produced glass by the fluorine-based gas is suppressed as much as possible to prevent the deposition rate from decreasing. Is intended to provide.

【０００９】[0009]

【課題を解決するための手段】かかる目的を達成するた
めに、本発明は、フッ素ドープ石英ガラスをプラズマ外
付け法で出発部材の周囲に形成するに際し、出発部材の
長さ方向に直交してプラズマトーチを対向させ、このプ
ラズマトーチから放射されるプラズマ炎と同軸上に石英
ガラス原料ガスを供給すると同時に、これと異なる方向
から、プラズマ炎中にフッ素系ガスを供給することを特
徴としている。In order to achieve the above object, the present invention provides a method of forming a fluorine-doped quartz glass around a starting member by a plasma external attachment method in a direction orthogonal to the longitudinal direction of the starting member. The plasma torch is made to face each other, and the quartz glass raw material gas is supplied coaxially with the plasma flame emitted from the plasma torch, and at the same time, a fluorine-based gas is supplied into the plasma flame from a different direction.

【００１０】[0010]

【作用】本発明のフッ素ドープ石英ガラスの製造方法に
よれば、プラズマ炎と同軸上に石英ガラス原料ガスを供
給すると同時に、これと異なる方向から、プラズマ炎中
にフッ素系ガスを供給するので、石英ガラス原料ガスと
フッ素系ガスを同時にプラズマ炎中に供給していた従来
の方法に比べ、フッ素系ガス量を石英ガラス原料ガスと
は別に独立して制御できるため、フッ素系ガスによる生
成ガラスのエッチングを抑制して安定したディポジショ
ン速度を得ることができる。According to the method for producing fluorine-doped quartz glass of the present invention, the quartz glass raw material gas is fed coaxially with the plasma flame, and at the same time, the fluorine-based gas is fed into the plasma flame from a different direction. Compared to the conventional method in which the quartz glass raw material gas and the fluorine-based gas were simultaneously supplied into the plasma flame, the amount of the fluorine-based gas can be controlled independently of the quartz glass raw material gas, so It is possible to suppress etching and obtain a stable deposition rate.

【００１１】[0011]

【実施例】以下、本発明について詳しく説明する。図１
は、本発明のフッ素ドープ石英ガラス製造方法を示す図
である。図中符号１０は石英棒（出発部材）である。こ
の石英棒１０をその軸の周りに回転させつつ長手方向に
移動させながら、この移動方向に直交する方向から、石
英棒１０の表面に、プラズマ炎１１を放射する。プラズ
マ炎１１は、石英棒１０の長手方向に対して直交方向に
配置されプラズマ発生用のガスを含んだプラズマトーチ
１２の外周にコイル１３を巻き付け、そのコイル１３を
高周波電源１４に接続して電流を流すことによって発生
し、このプラズマトーチ１２先端より放射される。The present invention will be described in detail below. Figure 1
FIG. 3 is a diagram showing a method for producing fluorine-doped quartz glass of the present invention. In the figure, reference numeral 10 is a quartz rod (starting member). While rotating the quartz rod 10 around its axis in the longitudinal direction, a plasma flame 11 is radiated onto the surface of the quartz rod 10 from a direction orthogonal to the moving direction. The plasma flame 11 has a coil 13 wound around the outer circumference of a plasma torch 12 which is arranged in a direction orthogonal to the longitudinal direction of the quartz rod 10 and which contains a gas for plasma generation. Is generated by flowing the magnetic field and is radiated from the tip of the plasma torch 12.

【００１２】このプラズマ炎１１中には、プラズマ炎１
１と同軸上に、石英ガラス原料ガス（ＳｉＣｌ4、Ｏ2）
を供給する。ＳｉＣｌ4の供給量は、１００〜５００ｍ
ｌ／ｍｉｎ程度、Ｏ2の供給量は、２００〜１０００ｍ
ｌ／ｍｉｎ程度とするのが好ましい。In the plasma flame 11, the plasma flame 1
Quartz glass source gas (SiCl 4 , O 2 ) coaxial with 1
To supply. The supply amount of SiCl 4 is 100 to 500 m
About 1 / min, the supply amount of O 2 is 200 to 1000 m
It is preferably about 1 / min.

【００１３】またこれと同時に、プラズマ炎１１中に
は、プラズマ炎１１の軸に対して直交方向に配されたノ
ズル１５から、フッ素系ガス（ＳＦ6）を噴射する。Ｓ
Ｆ6の供給量は、１０〜２００ｍｌ／ｍｉｎ程度とする
のが好ましい。なお、ノズル１５は、プラズマ炎１１の
軸に対して直交方向に配置するに限らず、プラズマ炎１
１中に効率良くガスを供給できれば、プラズマ炎１１に
対して適当な角度を付けて配置してもよい。At the same time, a fluorine-based gas (SF 6 ) is injected into the plasma flame 11 from a nozzle 15 arranged in a direction orthogonal to the axis of the plasma flame 11. S
The supply amount of F 6 is preferably about 10 to 200 ml / min. The nozzle 15 is not limited to be arranged in a direction orthogonal to the axis of the plasma flame 11, but the plasma flame 1
As long as the gas can be efficiently supplied into 1, the plasma flame 11 may be arranged at an appropriate angle.

【００１４】この方法によれば、プラズマ炎１１中で、
ＳｉＣｌ4はＯ2と反応して直接ガラス化されＳｉＯ2が
形成される。また、ＳＦ6は分解してＦが生成し、この
Ｆがプラズマ炎１１中でＳｉＯ2にドープされる。こう
して生成されたＦドープＳｉＯ2が、石英棒１０の表面
に堆積される。According to this method, in the plasma flame 11,
SiCl 4 reacts with O 2 to directly vitrify and form SiO 2 . Further, SF 6 is decomposed to generate F, and this F is doped into SiO 2 in the plasma flame 11. The F-doped SiO 2 thus produced is deposited on the surface of the quartz rod 10.

【００１５】このように、本実施例の方法では、プラズ
マ炎１１と同軸上にＳｉＣｌ4とＯ2を供給すると同時
に、これと異なる方向から、プラズマ炎１１中にＳＦ6
を供給するので、ＳｉＣｌ4とＳＦ6を同時にプラズマ炎
中に供給していた従来の方法に比べ、ＳＦ6量のコント
ロールが容易であり、そのためにＳＦ6による生成ガラ
スのエッチングを極力抑制して、安定したディポジショ
ン速度を得ることができる。As described above, according to the method of this embodiment, SiCl 4 and O 2 are supplied coaxially with the plasma flame 11 and, at the same time, SF 6 is introduced into the plasma flame 11 from a different direction.
As compared with the conventional method in which SiCl 4 and SF 6 are simultaneously supplied into the plasma flame, it is easier to control the amount of SF 6 and therefore the etching of the produced glass by SF 6 is suppressed as much as possible. , You can get a stable deposition speed.

【００１６】以下、具体的な実施例を示して、本発明の
効果を明らかにする。 （実施例１）出発石英棒に、径５０ｍｍのものを使用
し、プラズマ炎と同軸上にＳｉＣｌ4を１００ｍｌ／ｍ
ｉｎ、Ｏ2を２００ｍｌ／ｍｉｎ供給し、同時にこのプ
ラズマ炎中に、このプラズマ炎の直交方向からＳＦ6を
５０ｍｌ／ｍｉｎで噴射した。こうして、石英棒の表面
にＦドープ石英ガラスを堆積させ。Hereinafter, the effects of the present invention will be clarified by showing concrete examples. (Example 1) A starting quartz rod having a diameter of 50 mm was used, and SiCl 4 was 100 ml / m coaxially with the plasma flame.
In, O 2 was supplied at 200 ml / min, and at the same time, SF 6 was injected into this plasma flame at a rate of 50 ml / min from the direction orthogonal to this plasma flame. Thus, F-doped quartz glass was deposited on the surface of the quartz rod.

【００１７】（比較例１）ＳｉＣｌ4、ＳＦ6とＯ2をと
もにプラズマ炎と同軸上にそれぞれ実施例１と同量供給
し、従来法によりフッ素ドープ石英ガラスを得た。(Comparative Example 1) SiCl 4 , SF 6 and O 2 were all supplied in the same amount as in Example 1 coaxially with the plasma flame, and a fluorine-doped quartz glass was obtained by a conventional method.

【００１８】実施例および比較例で得られたフッ素ドー
プ石英ガラスの比屈折率差（石英ガラスとの）を測定
し、結果を表１に示す。また、各例におけるディポジシ
ョン速度を測定し、表１に示す。The relative refractive index difference (with respect to quartz glass) of the fluorine-doped quartz glass obtained in Examples and Comparative Examples was measured, and the results are shown in Table 1. In addition, the deposition speed in each example was measured and is shown in Table 1.

【００１９】[0019]

【表１】 [Table 1]

【００２０】表１の結果から、実施例において、ディポ
ジション速度の安定したフッ素ドープ石英ガラスが得ら
れることが明らかとなった。From the results shown in Table 1, it was revealed that in the Examples, fluorine-doped quartz glass having a stable deposition rate was obtained.

【００２１】なお、実施例で用いた石英棒１０として高
純度のものを用いれば、これが光ファイバ用のコアとな
り、その周りに形成されたフッ素ドープ石英ガラスがク
ラッドとなる光ファイバ母材を得ることができる。さら
に石英棒１０として、Ｇｅなどのドーパントを含ませた
ものを使用することもできる。If a high-purity quartz rod 10 is used in the embodiment, this serves as a core for an optical fiber, and an optical fiber preform having a fluorine-doped quartz glass formed around it as a clad is obtained. be able to. Further, as the quartz rod 10, a substance containing a dopant such as Ge can be used.

【００２２】[0022]

【発明の効果】以上説明したように、本発明のフッ素ド
ープ石英ガラスの製造方法によれば、高い比屈折率差を
有するフッ素ドープ石英ガラスを、安定したディポジシ
ョン速度で製造することができる。As described above, according to the method for producing fluorine-doped quartz glass of the present invention, fluorine-doped quartz glass having a high relative refractive index difference can be produced at a stable deposition rate.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明のフッ素ドープ石英ガラスの製造方法の
一例を示す断面図である。FIG. 1 is a sectional view showing an example of a method for producing a fluorine-doped quartz glass of the present invention.

【図２】従来のフッ素ドープ石英ガラスの製造方法の例
を示す断面図である。FIG. 2 is a cross-sectional view showing an example of a conventional method for producing fluorine-doped quartz glass.

【符号の説明】[Explanation of symbols]

１０ 石英棒（出発部材） １１ プラズマ炎 10 Quartz rod (starting member) 11 Plasma flame

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 フッ素ドープ石英ガラスをプラズマ外付
け法で出発部材の周囲に形成するに際し、 出発部材の長さ方向に直交してプラズマトーチを対向さ
せ、このプラズマトーチから放射されるプラズマ炎と同
軸上に石英ガラス原料ガスを供給すると同時に、これと
異なる方向から、プラズマ炎中にフッ素系ガスを供給す
ることを特徴とするフッ素ドープ石英ガラスの製造方
法。1. When a fluorine-doped quartz glass is formed around a starting member by a plasma external attachment method, a plasma torch is opposed to the starting member at right angles to a lengthwise direction of the starting member, and a plasma flame emitted from the plasma torch. A method for producing a fluorine-doped quartz glass, which comprises supplying a quartz glass raw material gas coaxially and at the same time, supplying a fluorine-based gas into a plasma flame from a different direction.
JP10857493A 1993-05-10 1993-05-10 Production of fluorine-doped quartz glass Pending JPH06321552A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10857493A JPH06321552A (en) 1993-05-10 1993-05-10 Production of fluorine-doped quartz glass

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10857493A JPH06321552A (en) 1993-05-10 1993-05-10 Production of fluorine-doped quartz glass

Publications (1)

Publication Number Publication Date
JPH06321552A true JPH06321552A (en) 1994-11-22

Family

ID=14488272

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10857493A Pending JPH06321552A (en) 1993-05-10 1993-05-10 Production of fluorine-doped quartz glass

Country Status (1)

Country Link
JP (1) JPH06321552A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001322820A (en) * 2000-03-06 2001-11-20 Shin Etsu Chem Co Ltd Fluorine-containing synthetic quartz glass and its manufacturing method
FR2847893A1 (en) * 2002-12-02 2004-06-04 Cit Alcatel METHOD AND DEVICE FOR PLASMA RECHARGING OF A PREFORM FOR OPTICAL FIBER WITH REDUCED NITROGEN OXIDES
KR100695036B1 (en) * 2006-02-20 2007-03-14 엄환섭 High-temperature large-volume plasma gas-scrubber
EP2206689A1 (en) * 2008-12-26 2010-07-14 Shin-Etsu Chemical Co., Ltd. Method and apparatus for manufacturing optical fiber preform using high frequency induction thermal plasma torch
JP2012512798A (en) * 2008-12-19 2012-06-07 ジェイ−ファイバー ゲーエムベーハー Multi-nozzle tubular plasma deposition burner for producing preforms as semi-finished products for optical fibers

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001322820A (en) * 2000-03-06 2001-11-20 Shin Etsu Chem Co Ltd Fluorine-containing synthetic quartz glass and its manufacturing method
FR2847893A1 (en) * 2002-12-02 2004-06-04 Cit Alcatel METHOD AND DEVICE FOR PLASMA RECHARGING OF A PREFORM FOR OPTICAL FIBER WITH REDUCED NITROGEN OXIDES
EP1426340A1 (en) 2002-12-02 2004-06-09 Alcatel Process and apparatus for overcladding an optical fibre preform by plasma
KR100695036B1 (en) * 2006-02-20 2007-03-14 엄환섭 High-temperature large-volume plasma gas-scrubber
JP2012512798A (en) * 2008-12-19 2012-06-07 ジェイ−ファイバー ゲーエムベーハー Multi-nozzle tubular plasma deposition burner for producing preforms as semi-finished products for optical fibers
EP2206689A1 (en) * 2008-12-26 2010-07-14 Shin-Etsu Chemical Co., Ltd. Method and apparatus for manufacturing optical fiber preform using high frequency induction thermal plasma torch

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