JP2881930B2 - Manufacturing method of quartz glass for optical transmission - Google Patents
Manufacturing method of quartz glass for optical transmissionInfo
- Publication number
- JP2881930B2 JP2881930B2 JP7974790A JP7974790A JP2881930B2 JP 2881930 B2 JP2881930 B2 JP 2881930B2 JP 7974790 A JP7974790 A JP 7974790A JP 7974790 A JP7974790 A JP 7974790A JP 2881930 B2 JP2881930 B2 JP 2881930B2
- Authority
- JP
- Japan
- Prior art keywords
- quartz glass
- optical transmission
- oxygen
- oxidizing agent
- plasma
- 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.)
- Expired - Fee Related
Links
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
- C03B19/00—Other methods of shaping glass
- C03B19/14—Other methods of shaping glass by gas- or vapour- phase reaction processes
- C03B19/1415—Reactant delivery systems
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/02—Pure silica glass, e.g. pure fused quartz
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/30—For glass precursor of non-standard type, e.g. solid SiH3F
- C03B2207/32—Non-halide
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/36—Fuel or oxidant details, e.g. flow rate, flow rate ratio, fuel additives
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は光伝送用石英ガラスの製造方法に関する。さ
らに詳しくは、酸素過剰や酸素不足による欠陥が少な
く、従って光伝送損失の少ない光ファイバー通信に適し
た光伝送用石英ガラスの製造方法に関する。The present invention relates to a method for producing quartz glass for optical transmission. More specifically, the present invention relates to a method for producing quartz glass for optical transmission, which has few defects due to oxygen excess or oxygen deficiency, and is therefore suitable for optical fiber communication with small optical transmission loss.
光ファイバー通信に使用される光ファイバーのコア材
については、光伝送損失を低減する研究が進められてお
り、例えば石英ガラス材コアについてはOHイオンの除去
などを含む材料の高純度化技術や屈折率制御技術の進歩
によって光伝送の低損失化が図られているが、更にその
向上が望まれている。Research is being conducted on reducing the optical transmission loss of optical fiber core materials used in optical fiber communications.For example, for silica glass cores, high-purity technologies for materials including removal of OH ions and refractive index control Although the loss of optical transmission has been reduced by the progress of technology, further improvement is desired.
光ファイバー用石英ガラスは、現在主に、煤付け法に
よって製造されているが、この他にプラズマを用いるプ
ラズマ法が知られている。従来知られているプラズマ法
は酸素プラズマを用いる方法であり、その概略は、特公
昭48-16330号等に記載されているように、ケイ素化合物
を酸素プラズマ中に導入して酸化分解し、生成した溶融
状態のシリカを基板上に堆積し透明な塊として得る。Quartz glass for optical fibers is currently mainly manufactured by a sooting method, but a plasma method using plasma is also known. The conventionally known plasma method is a method using oxygen plasma, and the outline thereof is, as described in JP-B-48-16330, etc., by introducing a silicon compound into oxygen plasma and oxidizing and decomposing the compound. The melted silica is deposited on the substrate to obtain a transparent mass.
この酸素プラズマは酸素もしくは酸素とアルゴンの混
合ガス流（容量比：O2/Ar＝3/2）を高周波誘導プラズマ
トーチ等で加熱してつくられる。The oxygen plasma is formed by heating a flow of oxygen or a mixed gas of oxygen and argon (volume ratio: O 2 / Ar = 3/2) with a high frequency induction plasma torch or the like.
この酸素プラズマ法に対して、アルゴンガス流中に少
量の酸素を加えたいわゆるアルゴンプラズマ法によって
も石英ガラスが得られるが、原料ケイ素化合物からの石
英ガラスの生成効率は酸素プラズマ法がアルゴンプラズ
マ法により数倍よいため、酸素プラズマ法が主流となっ
ているのが現状である。ところが酸素プラズマ法は、生
成する石英ガラス中の酸素原子が過剰になり易い問題が
ある。この過剰酸素は、製造条件によっては≡Si−Ｏ−
Ｏ−Si≡のようなパーオキシリンケージや酸素分子の形
で石英ガラスのネットワークを不均質にし、特に紫外領
域で吸収帯を生ずる。さらに酸素過剰の他の問題点は、
酸素量の微小変動によりプラズマ温度の変化が著しく、
ガラス状態が不均一になり易くやはり光の吸収が起るこ
とである。このような酸素過剰欠陥を有するものは光伝
送の際に吸収帯を生じて光伝送損失が大きくなるため遠
距離伝送用光ファイバーのコア材としては適当でない。In contrast to this oxygen plasma method, quartz glass can be obtained by the so-called argon plasma method in which a small amount of oxygen is added to an argon gas flow. At present, the oxygen plasma method is the mainstream because it is several times better. However, the oxygen plasma method has a problem that oxygen atoms in generated quartz glass are likely to be excessive. This excess oxygen can be reduced depending on the production conditions.
It makes the network of quartz glass inhomogeneous in the form of peroxylinkage or oxygen molecules such as O-Si≡ and produces absorption bands, especially in the ultraviolet region. Another problem with excess oxygen is that
The change in plasma temperature is remarkable due to the minute fluctuation of the oxygen amount.
That is, the glass state tends to be non-uniform, which also causes light absorption. Those having such an oxygen excess defect are not suitable as a core material of an optical fiber for long-distance transmission because an absorption band is generated during optical transmission and optical transmission loss increases.
本発明は、アルゴンプラズマ法によって従来の酸素プ
ラズマ法の問題を解決した光伝送損失の少ない優れた伝
送特性を有する石英ガラスの製造方法を提供する。The present invention provides a method for producing quartz glass having excellent transmission characteristics with little optical transmission loss, which has solved the problems of the conventional oxygen plasma method by the argon plasma method.
本発明によれば、高純度ケイ素化合物と酸化剤とをア
ルゴンプラズマ流に供給して生成するガラス状の酸化ケ
イ素を基板上に堆積固化させる石英ガラスの製造方法で
あって、酸化剤の量を高純度ケイ素化合物に対して化学
当量で0.6〜1.2倍量に制御することを特徴とする光伝送
用石英ガラスの製造方法が提供される。According to the present invention, there is provided a method for producing quartz glass in which a high-purity silicon compound and an oxidizing agent are supplied to an argon plasma flow to deposit and solidify glassy silicon oxide generated on a substrate, wherein the amount of the oxidizing agent is reduced. A method for producing quartz glass for optical transmission characterized by controlling the chemical equivalent to 0.6 to 1.2 times the amount of a high-purity silicon compound.
さらに、上記製造方法において、高純度ケイ素化合物
に対する酸化剤の量を制御することにより、光伝送損失
が650nmの波長で5.8〜12.7（dB/km）、830nmの波長で4.
0〜6.1（dB/km）である光伝送用石英ガラスを製造する
方法が提供される 本発明はアルゴンプラズマ法を用いる石英ガラスの製
造方法である。アルゴンプラズマはアルゴンガス流を高
周波誘導プラズマトーチ炉に導く公知の方法によって形
成される。本発明はアルゴンプラズマの中に酸化可能な
高純度ケイ素化合物と酸素原子を含む酸化剤とを供給
し、ケイ素化合物を酸化分解して、生成したガラス状の
酸化ケイ素を基板上に堆積し、固化して透明な石英ガラ
ス塊を製造する方法である。Further, in the above production method, by controlling the amount of the oxidizing agent with respect to the high-purity silicon compound, the optical transmission loss is 5.8 to 12.7 (dB / km) at a wavelength of 650 nm, and 4.
The present invention provides a method for producing quartz glass for optical transmission having a wavelength of 0 to 6.1 (dB / km). The present invention is a method for producing quartz glass using an argon plasma method. The argon plasma is formed by a known method of directing an argon gas flow into a high frequency induction plasma torch furnace. The present invention supplies an oxidizable high-purity silicon compound and an oxidizing agent containing oxygen atoms in an argon plasma, oxidizes and decomposes the silicon compound, deposits the generated glassy silicon oxide on a substrate, and solidifies it. To produce a transparent quartz glass block.
本発明の石英ガラスの原料となる酸化可能な高純度ケ
イ素化合物としては、たとえば四塩化ケイ素、トリクロ
ルシラン、ジクロルシランおよびモノシラン等が挙げら
れ、不純物量が10ppm以下のものが用いられる。Examples of the oxidizable high-purity silicon compound as a raw material of the quartz glass of the present invention include silicon tetrachloride, trichlorosilane, dichlorosilane, and monosilane, and those having an impurity amount of 10 ppm or less are used.
不純物である他の金属元素の存在は得られる石英ガラ
スにおいて特に紫外領域に望ましくない吸収帯を生じる
ので赤外域伝送には適さない。The presence of other metal elements, which are impurities, is not suitable for infrared transmission since the resulting quartz glass produces an undesirable absorption band especially in the ultraviolet region.
本発明の酸化剤としては精製した酸素が好適に用いら
れる。As the oxidizing agent of the present invention, purified oxygen is preferably used.
またアルゴンガスは市販の高純度品を用いることがで
きる。As the argon gas, a commercially available high-purity product can be used.
本発明の石英ガラスの製造方法においては酸化剤の量
が前記ケイ素化合物の量に対して、化学当量で0.6〜1.2
倍の範囲に定められる。In the method for producing quartz glass of the present invention, the amount of the oxidizing agent is 0.6 to 1.2 in chemical equivalent to the amount of the silicon compound.
The range is set to double.
酸化剤の量が、ケイ素化合物の量に対し化学当量の1.
2倍以上になると、酸素プラズマ法を用いる場合と同様
に、得られる石英ガラス中の酸素原子が過剰となりやす
い。この過剰の酸素は、反応条件により≡Si−Ｏ−Ｏ−
Si≡のようなパーオキシリンケージや酸素分子の形で石
英ガラスのネットワーク中に存在し、ネットワークを不
均一にし、特に163nm、325nm、600〜630nm等の帯域に吸
収を生じ、いわゆる酸素過剰欠陥が増大して光伝送損失
増加の原因となるので好ましくない。また酸化剤の量が
ケイ素化合物の量に対し化学当量の0.6倍以下では、原
料ケイ素化合物から生成する酸化ケイ素の量が減少し、
製品歩留りが下がる。また得られる石英ガラスが酸素原
子不足となり、酸素空孔による欠陥を生じ、215nm、225
nmおよび245nmの紫外領域に吸収を起して光伝送損失を
生ずること等の理由により好ましくない。The amount of the oxidizing agent is 1.
If it is twice or more, oxygen atoms in the obtained quartz glass tend to be excessive as in the case of using the oxygen plasma method. This excess oxygen can be reduced by 反 応 Si—O—O—
It exists in the network of quartz glass in the form of peroxylinkage and oxygen molecules such as Si≡, and makes the network non-uniform, causing absorption in the bands such as 163 nm, 325 nm, and 600 to 630 nm. It is not preferable because it causes an increase in optical transmission loss. When the amount of the oxidizing agent is 0.6 times or less of the chemical equivalent to the amount of the silicon compound, the amount of silicon oxide generated from the starting silicon compound decreases,
Product yield decreases. In addition, the resulting quartz glass becomes deficient in oxygen atoms, causing defects due to oxygen vacancies, 215 nm, 225 nm
It is not preferable because it causes absorption in the ultraviolet region of nm and 245 nm to cause optical transmission loss.
原料の四塩化ケイ素ガス等は酸素ガス及びアルゴンガ
スと共に高周波プラズマトーチに供給され、高周波加熱
されて四塩化ケイ素の酸化により生じた二酸化ケイ素が
プラズマガス流と共に耐火物基板上に衝突し、該基板上
にガラス状の透明石英ガラスが形成される。この石英ガ
ラスは引伸ばして光ファイバーのコア材として用いられ
る。The raw material silicon tetrachloride gas and the like are supplied to a high-frequency plasma torch together with oxygen gas and argon gas, and silicon dioxide generated by oxidation of silicon tetrachloride by high-frequency heating collides with the plasma gas flow on the refractory substrate, and A glassy transparent quartz glass is formed thereon. This quartz glass is stretched and used as a core material of an optical fiber.
以上述べたように本発明の製造方法においては、アル
ゴンプラズマ中にケイ素化合物と酸化剤とを導入するの
で、酸素プラズマ法に較べて導入する酸素量を極めて正
確に特定の範囲に制御することができ酸素過剰および酸
素不足による欠陥がなく、光伝送損失の少ない優れた光
伝送特性の石英ガラスを製造することができる。具体的
には、実施例に示すように、光伝送損失が650nmの波長
で5.8〜12.7（dB/km）、830nmの波長で4.0〜6.1（dB/l
m）の石英ガラスを得ることができる。As described above, in the production method of the present invention, since the silicon compound and the oxidizing agent are introduced into the argon plasma, it is possible to control the amount of oxygen to be introduced to a specific range extremely accurately as compared with the oxygen plasma method. As a result, it is possible to manufacture quartz glass having excellent light transmission characteristics with no defects due to oxygen excess and oxygen shortage and low optical transmission loss. Specifically, as shown in the examples, the optical transmission loss is 5.8 to 12.7 (dB / km) at a wavelength of 650 nm and 4.0 to 6.1 (dB / l) at a wavelength of 830 nm.
m) quartz glass can be obtained.
なお、本発明の製造方法は各種のドーパントを導入す
る場合にも好適に適用することができる。The manufacturing method of the present invention can be suitably applied to the case where various dopants are introduced.
本発明の実施例を比較例と共に以下に示す。 Examples of the present invention are shown below together with comparative examples.
実施例１ 高周波誘導プラズマトーチに、高純度の四塩化ケイ
素、アルゴンおよび酸素を第１表の流量で供給して、ア
ルゴンプラズマ中で四塩化ケイ素を酸化し基板上に石英
ガラスを形成した。得られた石英ガラスの重量よりケイ
素収率は62％であった。Example 1 High-purity silicon tetrachloride, argon and oxygen were supplied at a flow rate shown in Table 1 to a high-frequency induction plasma torch, and silicon tetrachloride was oxidized in argon plasma to form quartz glass on a substrate. The silicon yield was 62% based on the weight of the obtained quartz glass.
この石英塊をロッド状に成形した後、外径200μｍの
ファイバーに延伸し、これにシリコーン樹脂のクラッド
を被覆して外径300μｍファイバーとした。After forming this quartz lump into a rod shape, it was drawn into a fiber having an outer diameter of 200 μm, and this was coated with a silicone resin clad to obtain a fiber having an outer diameter of 300 μm.
この光ファイバーについて、650nmおよび830nmの波長
における光伝送損失を測定して第１表の結果を得た。With respect to this optical fiber, the optical transmission loss was measured at wavelengths of 650 nm and 830 nm, and the results shown in Table 1 were obtained.
実施例２〜４ 実施例１において、酸素の流量を第１表に示したよう
に変え、他の条件は実施例１と全く同一にして石英ガラ
スを製造し、ケイ素収率を求め、得られた石英ガラスよ
り実施例１と同様にして外径300μｍの光ファイバーを
つくり、650nmと830nmにおける光伝送損失を測定した。
結果を第１表に示した。Examples 2 to 4 In Example 1, the flow rate of oxygen was changed as shown in Table 1 and the other conditions were exactly the same as in Example 1 to produce quartz glass, and the silicon yield was obtained. An optical fiber having an outer diameter of 300 μm was made from the quartz glass in the same manner as in Example 1, and the optical transmission loss at 650 nm and 830 nm was measured.
The results are shown in Table 1.
比較例１ 酸素プラズマ法により製造した石英ガラスを用いて、
実施例１と同様にして外径300μｍの光ファイバーを製
造し、同様に光伝送損失を測定した。結果を第１表に並
記した。Comparative Example 1 Using quartz glass manufactured by the oxygen plasma method,
An optical fiber having an outer diameter of 300 μm was manufactured in the same manner as in Example 1, and the optical transmission loss was measured in the same manner. The results are shown in Table 1.
比較例２、３ 実施例１において、アルゴンプラズマ中の酸素流量を
第１表のように本発明の範囲より過剰もしくは過少の条
件で製造した石英ガラスを用いて光ファイバーとし、同
様に光伝送損失を測定した結果を第１表に掲げて比較し
た。Comparative Examples 2 and 3 In Example 1, an optical fiber was formed using quartz glass manufactured under conditions in which the oxygen flow rate in the argon plasma was too large or too small as shown in Table 1, and the optical transmission loss was similarly reduced. The measured results are listed in Table 1 and compared.
以上の実施例および比較例で明らかなように、本発明
に係るアルゴンプラズマ法による光ファイバーの伝送損
失は比較例に比べて大幅に少ない。As is clear from the above examples and comparative examples, the transmission loss of the optical fiber by the argon plasma method according to the present invention is significantly smaller than that of the comparative example.
なお、酸素の四塩化ケイ素に対する当量比が0.5まで
減少すると、光伝送損失の改善は少なく、ケイ素収率が
低下する傾向がある。When the equivalent ratio of oxygen to silicon tetrachloride decreases to 0.5, the improvement in light transmission loss is small and the silicon yield tends to decrease.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) C03B 8/04 C03B 19/14 C03B 20/00 ──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. 6 , DB name) C03B 8/04 C03B 19/14 C03B 20/00
Claims (2)
プラズマ流に供給して生成するガラス状の酸化ケイ素を
基板上に堆積固化させる石英ガラスの製造方法であっ
て、酸化剤の量を高純度ケイ素化合物に対して化学当量
で0.6〜1.2倍量に制御することを特徴とする光伝送用石
英ガラスの製造方法。1. A method for producing quartz glass, comprising depositing and solidifying glassy silicon oxide produced by supplying a high-purity silicon compound and an oxidizing agent to an argon plasma stream on a substrate, wherein the amount of the oxidizing agent is high. A method for producing silica glass for optical transmission, characterized in that the chemical equivalent is controlled to 0.6 to 1.2 times the chemical equivalent of the pure silicon compound.
制御することにより、光伝送損失が650nmの波長で5.8〜
12.7（dB/km）、830nmの波長で4.0〜6.1（dB/km）であ
る光伝送用石英ガラスを製造する請求項１に記載の製造
方法。2. An optical transmission loss of 5.8 to 650 nm at a wavelength of 650 nm by controlling the amount of the oxidizing agent with respect to the high-purity silicon compound.
The manufacturing method according to claim 1, wherein quartz glass for optical transmission having a wavelength of 12.7 (dB / km) and 4.0 to 6.1 (dB / km) at a wavelength of 830 nm is manufactured.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7974790A JP2881930B2 (en) | 1990-03-28 | 1990-03-28 | Manufacturing method of quartz glass for optical transmission |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7974790A JP2881930B2 (en) | 1990-03-28 | 1990-03-28 | Manufacturing method of quartz glass for optical transmission |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03279231A JPH03279231A (en) | 1991-12-10 |
| JP2881930B2 true JP2881930B2 (en) | 1999-04-12 |
Family
ID=13698821
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7974790A Expired - Fee Related JP2881930B2 (en) | 1990-03-28 | 1990-03-28 | Manufacturing method of quartz glass for optical transmission |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2881930B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3794664B2 (en) | 1998-07-29 | 2006-07-05 | 信越化学工業株式会社 | Synthetic quartz glass member, manufacturing method thereof, and optical component for excimer laser |
| JP2001019465A (en) * | 1999-07-07 | 2001-01-23 | Shin Etsu Chem Co Ltd | Synthetic quartz glass member for excimer laser and its production |
-
1990
- 1990-03-28 JP JP7974790A patent/JP2881930B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03279231A (en) | 1991-12-10 |
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