JPH0497922A - Optical member for ultraviolet laser - Google Patents
Optical member for ultraviolet laserInfo
- Publication number
- JPH0497922A JPH0497922A JP21025290A JP21025290A JPH0497922A JP H0497922 A JPH0497922 A JP H0497922A JP 21025290 A JP21025290 A JP 21025290A JP 21025290 A JP21025290 A JP 21025290A JP H0497922 A JPH0497922 A JP H0497922A
- Authority
- JP
- Japan
- Prior art keywords
- glass body
- optical member
- ultraviolet laser
- silica glass
- synthetic silica
- 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
- 230000003287 optical effect Effects 0.000 title claims abstract description 21
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 31
- 239000011521 glass Substances 0.000 claims abstract description 21
- 239000007789 gas Substances 0.000 claims abstract description 16
- 238000011282 treatment Methods 0.000 claims abstract description 15
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 12
- 238000001513 hot isostatic pressing Methods 0.000 claims abstract description 10
- 239000011261 inert gas Substances 0.000 claims abstract description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 9
- 239000001301 oxygen Substances 0.000 claims description 9
- 229910052760 oxygen Inorganic materials 0.000 claims description 9
- 206010040925 Skin striae Diseases 0.000 claims description 3
- 229910052804 chromium Inorganic materials 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 229910052744 lithium Inorganic materials 0.000 claims description 3
- 229910052759 nickel Inorganic materials 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 3
- 229910052783 alkali metal Inorganic materials 0.000 claims description 2
- 150000001340 alkali metals Chemical class 0.000 claims description 2
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims description 2
- 150000001342 alkaline earth metals Chemical class 0.000 claims description 2
- 229910052791 calcium Inorganic materials 0.000 claims description 2
- 229910052749 magnesium Inorganic materials 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
- 229910052723 transition metal Inorganic materials 0.000 claims description 2
- 150000003624 transition metals Chemical class 0.000 claims description 2
- 239000010953 base metal Substances 0.000 abstract 1
- 238000000034 method Methods 0.000 description 11
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 10
- 229910001882 dioxygen Inorganic materials 0.000 description 10
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 238000002834 transmittance Methods 0.000 description 8
- 238000010521 absorption reaction Methods 0.000 description 7
- 238000010438 heat treatment Methods 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 230000008859 change Effects 0.000 description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 239000001307 helium Substances 0.000 description 5
- 229910052734 helium Inorganic materials 0.000 description 5
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- BJQHLKABXJIVAM-UHFFFAOYSA-N bis(2-ethylhexyl) phthalate Chemical compound CCCCC(CC)COC(=O)C1=CC=CC=C1C(=O)OCC(CC)CCCC BJQHLKABXJIVAM-UHFFFAOYSA-N 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 238000010411 cooking Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000007872 degassing Methods 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000006552 photochemical reaction Methods 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000004071 soot Substances 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 1
- 101000880156 Streptomyces cacaoi Subtilisin inhibitor-like protein 1 Proteins 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 1
- OYLGJCQECKOTOL-UHFFFAOYSA-L barium fluoride Chemical compound [F-].[F-].[Ba+2] OYLGJCQECKOTOL-UHFFFAOYSA-L 0.000 description 1
- 229910001632 barium fluoride Inorganic materials 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- 229910001634 calcium fluoride Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 150000002222 fluorine compounds Chemical class 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 230000005865 ionizing radiation Effects 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- -1 is the same Chemical compound 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- ORUIBWPALBXDOA-UHFFFAOYSA-L magnesium fluoride Chemical compound [F-].[F-].[Mg+2] ORUIBWPALBXDOA-UHFFFAOYSA-L 0.000 description 1
- 229910001635 magnesium fluoride Inorganic materials 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000003947 neutron activation analysis Methods 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000011265 semifinished product Substances 0.000 description 1
- 239000005049 silicon tetrachloride Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Landscapes
- Glass Compositions (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は、略３６０ｒ＋ｍ以下の高出力紫外光、より具
体的にはＫｒＦ若しくはＡｒＦエキシマレーザ光、ＹＡ
Ｇ４倍高調波（略２５０ｎｍ）レーザ光その他の高出力
紫外線レーザ光を利用した各種装置に組込まれるレンズ
、プリズム、フィルタ、ウィンドウ５ ミラ、エタロン
板若しくはこれらの部材の最終仕上げ加工前の半製品と
して機能し得る紫外線レーザ用光学部材に関する。Detailed Description of the Invention <Industrial Application Field> The present invention is directed to high-output ultraviolet light of about 360r+m or less, more specifically KrF or ArF excimer laser light, YA
Lenses, prisms, filters, windows, mirrors, etalon plates, etc. that are incorporated into various devices that use G4 harmonic (approximately 250 nm) laser light and other high-power ultraviolet laser light, or semi-finished products before final finishing of these parts. The present invention relates to a functional optical member for an ultraviolet laser.
〈従来技術〉
近年、エレキシマレーザやＹＡＧ４倍高調波をはじめと
する波長変換紫外線レーザは、ＬＳＩ製造のためのリソ
グラフィー技術、光化学反応を利用する技術、切断研削
の為の加工技術、レーザ核融合技術に利用されるものと
して注目を集めている。<Prior art> In recent years, wavelength conversion ultraviolet lasers such as electric excimer lasers and YAG 4th harmonic have been developed using lithography technology for LSI manufacturing, technology using photochemical reactions, processing technology for cutting and grinding, and laser fusion. It is attracting attention as it is used in technology.
又紫外線レーザを透過、伝送、屈折、反射、吸収、干渉
させることにより制御するレンズ、プリズム、フィルタ
ー、ウィンドウ、ミラー、エタロン板、ファイバーの素
材としては、フッ化マグネシウム、フッ化カルシウム、
フッ化バリウム等のフッ化物もしくはシリカガラスが利
用できるが、加工性、寸法、脈理や屈折率の均質性から
シリカガラスが最もふされしいものである。In addition, materials for lenses, prisms, filters, windows, mirrors, etalon plates, and fibers that control ultraviolet lasers by transmitting, transmitting, refracting, reflecting, absorbing, and interfering with them include magnesium fluoride, calcium fluoride,
Fluorides such as barium fluoride or silica glass can be used, but silica glass is most suitable in terms of workability, size, homogeneity of striae and refractive index.
しかしながら、前記各種オブテイクスを構成するシリカ
ガラスは略３６０ｎｍから略１６０ｎｍの紫外波調域の
光が作用した場合、他の電離放射線、例えばＸ線やγ線
に比較して大幅に強い光学的ダメージを受けやすい。However, when the silica glass that constitutes the various objects mentioned above is exposed to light in the ultraviolet harmonic range from about 360 nm to about 160 nm, it causes much stronger optical damage than other ionizing radiation, such as X-rays and γ-rays. Easy to accept.
例えば、紫外線レーザが長時間照射されるとシリカガラ
スの網目構造が切断され、いわゆるＥ′センターと呼ば
れる略２１５ｎｍの吸収バンドと、別の略２６０ｎｍ吸
収バンドが生成し、略３６０ｎｍから略１６０ｎＩ１１
の透過率を低下させ、光学特性を劣化させてしまう、従
って、シリカガラスを前記波長域レーザに対して耐久性
を向上させることは構造上非常にむずかしい。For example, when an ultraviolet laser is irradiated for a long time, the network structure of silica glass is cut, and an absorption band of about 215 nm called the so-called E' center and another absorption band of about 260 nm are generated, and from about 360 nm to about 160 nI11
Therefore, it is structurally very difficult to improve the durability of silica glass against lasers in the wavelength range.
更にパルス発振レーザ、特に略２５０ｎｍ以下の短紫外
域におけるＫｒＦ若しくはＡｒＦエキシマレーザは、他
のあらゆる種類の紫外光に比較して最も強いエネルギー
を持っており、該エキシマレーザの照射により一層強い
光学的ダメージを受けやすいことが確認されている。Furthermore, pulsed lasers, especially KrF or ArF excimer lasers in the short ultraviolet region of approximately 250 nm or less, have the strongest energy compared to all other types of ultraviolet light, and irradiation with the excimer laser produces even stronger optical effects. It has been confirmed that it is susceptible to damage.
〈発明が解決しようとする課題〉
かかる欠点を解消するために１本出願人は全方向脈理フ
リーで複屈折も認められず、泡及び蛍光の発生もない高
純度高均質性の５ＵＰＲＡＳＩＬ−ＰＩＯｌＳＵＰＲＡ
ＳＩＬ−１，５ＵＰＲＡＳＩＬ−Ｗ ｌ、（商品名、信
越石英株式会社製）等の合成シリカガラス体を開発した
が、かかるガラス体はｘｉや３６０■以上の近紫外線に
は有効であるが、略３６０ｒ＋ｍ以下の短紫外域レーザ
、特に略２５０ｎｍ以下の短紫外域におけるＫｒＦ若し
くはＡｒＦエキシマレーザの照射においてはダメージが
極めて大きかった。<Problems to be Solved by the Invention> In order to eliminate such drawbacks, the applicant has developed a highly pure and highly homogeneous 5UPRASIL-PIOlSUPRA that is free of striae in all directions, has no birefringence, and does not generate bubbles or fluorescence.
We have developed synthetic silica glass bodies such as SIL-1, 5 UPRASIL-W l (trade name, manufactured by Shin-Etsu Quartz Co., Ltd.), but such glass bodies are effective against near ultraviolet rays of xi and 360 μ or more, but Irradiation with a short ultraviolet laser of 360 r+m or less, particularly KrF or ArF excimer laser irradiation in a short ultraviolet region of about 250 nm or less, caused extremely large damage.
本発明はかかる従来技術の欠点に鑑み、耐レーザ性と高
透過率を保証し得る紫外線レーザ用光学部材を提供する
事を目的とする。In view of the drawbacks of the prior art, it is an object of the present invention to provide an optical member for an ultraviolet laser that can ensure laser resistance and high transmittance.
く課題を解決するための手段〉
本発明者は、シリカガラス中の酸素ガスの存在が耐紫外
線レーザ性に強い影響を与え、他の溶存ガス、例えば水
素ガスの含有濃度が同じであれば酸素ガス含有濃度が高
ければ高いほど耐紫外線レーザ性が低下することを見出
し、高純度高均質の合成シリカガラス体、特にＯＨ基を
１０重量ｐｐｍ以上含有させた高純度高均質の合成シリ
カガラス体を出発母材とし、該ガラス体を例えば不活性
ガス雰囲気下で且つ高温高圧下で所定時間維持させて、
該ガラス体中に含有する。２ガスを実質的に除去。Means for Solving the Problems> The present inventor has discovered that the presence of oxygen gas in silica glass has a strong influence on ultraviolet laser resistance, and that if the concentration of other dissolved gases, such as hydrogen gas, is the same, oxygen We discovered that the higher the gas content concentration, the lower the UV laser resistance, and we developed a high-purity, highly homogeneous synthetic silica glass body, especially a high-purity, highly homogeneous synthetic silica glass body containing 10 ppm by weight or more of OH groups. As a starting base material, the glass body is maintained for a predetermined period of time under an inert gas atmosphere and under high temperature and high pressure,
contained in the glass body. 2 gases are substantially removed.
より具体的には前記ガラス体中の０２含有量を、真空中
１０００℃昇温時における酸素分子放出量換算で、略ｈ
Ｘ １０” （ｍｏｌｅｃｕｌｅｓ／ｒｌ（）以下に
設定した紫外線レーザ用光学部材を提案する。More specifically, the 02 content in the glass body is approximately h in terms of the amount of oxygen molecules released when the temperature is raised to 1000°C in vacuum.
We propose an optical member for ultraviolet laser that is set to less than X 10'' (molecules/rl()).
尚、前記高均質の合成シリカガラス体とは、三軸方向の
調理が除去され且つ屈折率変動幅（Δｎ）を２×１０−
６以下に設定したガラス体を指し、又高純度の合成シリ
カガラス体とは、 Ｌｉ、Ｎａ及びＫからなるアルカリ
金属含有量を１５０ｐｐｂ以下、Ｍｇ及びＣａからなる
アルカリ土類金属含有量を１ｏｏｐｐｂ以下、 Ｔｉ、
Ｃｒ、Ｆｅ、Ｎｉ及びＣｕの遷移金属含有量を５ｏｐｐ
ｂ以下に設定したガラス体をさす。The highly homogeneous synthetic silica glass body is one in which cooking in the triaxial direction is removed and the refractive index variation width (Δn) is 2×10 −
6 or less, and a high-purity synthetic silica glass body has an alkali metal content of Li, Na, and K of 150 ppb or less, and an alkaline earth metal content of Mg and Ca of 1 ooppb or less. , Ti,
The transition metal content of Cr, Fe, Ni and Cu is 5opp.
Refers to a glass body set below b.
又本発明はＫｒＦ若しくはＡｒＦエキシマレーザ光、Ｙ
ＡＧ４倍高調波（略２５０ｎｍ）レーザ光に有効である
が、これのみに限定されない。The present invention also provides KrF or ArF excimer laser light, Y
Although it is effective for AG4 harmonic (approximately 250 nm) laser light, it is not limited to this.
「作用」
さて、このように酸素ガスの存在が何故耐紫外線レーザ
性に悪影響を及ぼすのか明確でないが、下記の様に推測
される。"Effect" Now, it is not clear why the presence of oxygen gas has such a negative effect on ultraviolet laser resistance, but it is speculated as follows.
即ち、シリカガラス体に紫外線が照射されると、該ガラ
ス体中の含有酸素ガスが紫外線エネルギーを吸収して光
化学反応により各種励起体、例えば０．０２，０３が生
成し、これらの励起体が石英ガラス構造中の酸素元素に
エネルギーを伝達し、結果として石英ガラス構造中の網
目構造を切断してＥ′センター（イープライムセンター
）やＮＢＯＨセンター（ノンブリッジオキシジエンホー
ルセンター）等の吸収バンドを形成するものと思慮され
る。That is, when a silica glass body is irradiated with ultraviolet rays, the oxygen gas contained in the glass body absorbs the ultraviolet energy, and various excited bodies, such as 0.02 and 0.03, are generated by a photochemical reaction, and these excited bodies Energy is transferred to the oxygen element in the silica glass structure, and as a result, the network structure in the silica glass structure is cut to create absorption bands such as the E' center (E-prime center) and NBOH center (non-bridge oxydiene hole center). It is considered to form.
この為本出願人は先に前記ガラス体中に水素ガスをドー
プさせ前記Ｅ′センターやＮＢＯＨセンターと水素ガス
と反応させることにより前記吸収バンドを補修せんとす
る技術［特願平１−１４５２２６号］を提案し、かかる
技術も耐レーザ性を向上させるのに有効であるが、かか
る技術は０，０２，０３の生成を前提とする対処療法で
ある。For this reason, the present applicant has proposed a technique to repair the absorption band by first doping hydrogen gas into the glass body and causing the E' center and NBOH center to react with the hydrogen gas [Patent Application No. 1-145226] Although this technique is also effective in improving laser resistance, this technique is a countermeasure that assumes the generation of 0, 02, and 03.
又本出願人は更に、前記シリカガラス体の網目構造中に
存在する酸素欠陥を極力除去する技術［特願昭６３−２
１３６１号］も開示しているが、かかる技術も、酸素欠
陥が存在しないためにレーザ照射当初において前記吸収
バンドの形成が抑制されるが、前記シリカガラス体中に
含有酸素ガス〔分子としての酸素１が存在する限り０，
０．．０３が生成するという図式には変りがな（、結果
として経時的な耐レーザ性の低下を抑制しうるもこれを
完全には補償し得ない。The present applicant has also proposed a technique for removing as much as possible the oxygen defects present in the network structure of the silica glass body [Patent Application No. 63-2].
No. 1361], this technique also suppresses the formation of the absorption band at the beginning of laser irradiation due to the absence of oxygen defects; 0 as long as 1 exists,
0. ．． There is no change in the diagram that 03 is generated (as a result, although it is possible to suppress the decline in laser resistance over time, it cannot be completely compensated for.
そこで本発明は、前記励起体の生成を根本から除去する
ために、前記シリカガラス体中に含有する酸素ガス〔分
子としての酸素］自体を実質的に除去せんとするもので
ある。Therefore, the present invention aims to substantially remove the oxygen gas (oxygen as a molecule) itself contained in the silica glass body in order to fundamentally eliminate the generation of the excited body.
尚、前記ガラス体中に含有する０２ガスの除去は、単に
還元性若しくは真空雰囲気下で加熱処理したのみではそ
の除去は困難であり、そこで本発明は前記高純度高均質
の合成シリカガラス体を、ヘリウムやアルゴン等の希ガ
ス若しくは窒素ガスを含めたいわゆる不活性ガス雰囲気
下で且つ熱間等方圧加圧法（ＨＩＰ）処理にて所定時間
維持させて除去させている。It should be noted that it is difficult to remove the 02 gas contained in the glass body simply by heat treatment in a reducing or vacuum atmosphere. Therefore, the present invention provides a method for using the high purity and highly homogeneous synthetic silica glass body. , in an atmosphere of a so-called inert gas containing a rare gas such as helium or argon, or nitrogen gas, and maintained for a predetermined period of time by hot isostatic pressing (HIP).
尚、前記ガラス体中にＯＨ基を含有、より具体的には１
０重量ｐｐｍ以上のＯＨ基を含有させると、ＯＨ基の存
在が旧Ｐ処理時の高均質性の維持とともに耐紫外線レー
ザ性ともに好ましい影響が生じせしめる。Note that the glass body contains an OH group, more specifically, 1
When the OH group is contained in an amount of 0 ppm or more by weight, the presence of the OH group has a favorable effect on both the maintenance of high homogeneity during the prior P treatment and the ultraviolet laser resistance.
その理由は、ＯＨ基はガラス綱目構造の終端部となるも
ので、いわゆるネットワークターミネータである。この
ネットワークターミネータが適量存在すると、ガラス綱
目構造中の元素間の距離の狂いや元素間の結合角度のね
じれをリラックスさせて、安定化させ、更にＯＨ基の水
素がＥ′センター等の吸収バンドの修復に作用するもの
と推定される。The reason for this is that the OH group serves as the terminal end of the glass mesh structure, and is a so-called network terminator. When this network terminator exists in an appropriate amount, it relaxes and stabilizes the distances between elements in the glass network structure and the twisting of bond angles between elements, and furthermore, the hydrogen of the OH group causes absorption bands such as the E' center to be stabilized. It is presumed that it acts on repair.
〈実施例〉
先ず本発明者は、３軸方向における調理が除去されてお
り、先便用領域における屈折率変動幅（Δｎ）を２×１
０−”以下で且つ歪量を５ｎコ／ｃｍ以下に抑、ｔ、？
：：５ＵＰＲＡＳＩＬ Ｐ−１０ノ内、ＯＨ基が略７０
０重量ｐｐｎ＋のシリカガラス体を選択し５該シリ力ガ
ラス体を切断、研削加工して直径５０Ｘ”２０ｍｍの試
験片を作成した後、該試験片を、クリーンなステンレス
スチールジャケット内にタングステンヒータを配置した
電気炉内に設！し、Ｉ Ｘ ＩＰ２（Ｔｏｏｒ）以下の
真空雰囲気下で８００〜１０００℃に加熱しながら脱ガ
ス処理を行なった後、室温まで冷却した。この処理の目
的は２本発明の効果を明確に確認するため、耐紫外線レ
ーザ性に影響を与えるシリカガラス中の溶存ガスを同一
条件である程度脱ガスさせ実験上の出発材料として溶存
ガスに関して同一条件としておくためであり、工業上の
必須条件ではない。<Example> First, the present inventors determined that cooking in the three axial directions was removed and the refractive index variation width (Δn) in the first use area was reduced to 2×1.
0-" or less and suppress the amount of distortion to 5n/cm or less, t,?
::5UPRASIL P-10, OH group is approximately 70
A 0 weight ppn+ silica glass body was selected, and the silica glass body was cut and ground to create a test piece with a diameter of 50 x 20 mm.The test piece was placed in a clean stainless steel jacket with a tungsten heater. It was placed in an electric furnace and degassed while heating to 800 to 1000°C in a vacuum atmosphere below I In order to clearly confirm the effects of the invention, the dissolved gas in silica glass that affects ultraviolet laser resistance was degassed to some extent under the same conditions, and the same conditions were used for the dissolved gas as a starting material for the experiment. The above is not a necessary condition.
次に、前記試験片を２熱処理を行わないもの（Ｎｏ。Next, the test piece 2 was not subjected to heat treatment (No.
６）、ＨＩＰ処理法（熱間等方圧加圧法）により、アル
ゴンガス１００％雰囲気で、１０００℃、２０００ａｔ
ｍ２０ｈｒｓの処理を行なったもの（Ｎｏ、 １ ）
、同様の処理条件下でヘリウムガス１００％雰囲気で旧
Ｐ処理を行なったもの（Ｎｏ、２） 、同様の処理条件
下で酸素２０％チッ素８０％の雰囲気でＨＩＰ処理を行
なったもの（Ｎｏ、３）、前記脱ガス処理を行ったクリ
ーンな電気炉内でヘリウム１００％雰囲気で１０００℃
、ｌａｔｍ。6), 1000℃, 2000at in 100% argon gas atmosphere by HIP treatment method (hot isostatic pressing method)
Those processed for m20hrs (No. 1)
, those subjected to old P treatment in a 100% helium gas atmosphere under similar treatment conditions (No. 2), and those subjected to HIP treatment in an atmosphere of 20% oxygen and 80% nitrogen under similar treatment conditions (No. 2). , 3), 1000°C in a 100% helium atmosphere in a clean electric furnace that has undergone the degassing process.
, latm.
２０ｈｒｓの処理を行なったもの（Ｎｏ、４） 、大気
ガス雰囲気下でＮｏ、４と同様な処理で行なったもの（
Ｎｏ。20hrs treatment (No. 4), and No. 4 treated in the same way as No. 4 under an atmospheric gas atmosphere (No. 4).
No.
５）を用意し、次にこれらの処理済試験片を切断、研磨
加工し、２０Ｘ２０Ｘ’１ｍの酸素ガス放出量測定用サ
ンプル、３０Ｘ３０ＸｔｌＯｍの耐ＫｒＦエキシマレー
ザ性評価用サンプルを作成した。5) were prepared, and then these treated test pieces were cut and polished to create samples for measuring the amount of oxygen gas released measuring 20×20×′1 m and samples for evaluating KrF excimer laser resistance measuring 30×30×tlOm.
尚、酸素ガス測定は、前記サンプルをセットした石英チ
ャンバー内を真空雰囲気にした後、４℃／ｓｉｎで１０
００℃まで昇温させた後、該１０００℃にて２ｈｒ保持
する。その時放出される酸素ガスその他の各種ガスを四
重極型質量分析計に導入してその放出量を測定する方法
である。In addition, oxygen gas measurement was performed after creating a vacuum atmosphere in the quartz chamber in which the sample was set, and then heating at 4°C/sin for 10
After raising the temperature to 00°C, the temperature was maintained at 1000°C for 2 hours. In this method, oxygen gas and other various gases released at that time are introduced into a quadrupole mass spectrometer to measure the amount released.
又耐ＫｒＦエキシマレーザ性評価では、パルス当りのエ
ネルギー密度を４００ｍＪ／ ｅｒｒ！ 、 ｐとし、
１００Ｈｚにて連続照射を行ないながら、Ｅ′センター
吸収バンドの検出のため透過率計にて、５８ｅＶ （略
２１５ｎｍ）の透過率の経時変化を測定し、前記各サン
プルにおける内部透過率が１％低下するまでの照射パル
ス数と、屈折率の均質性を評価するために３０φエリア
における照射パルスＩ Ｘ １ｏ６Ｐｕｌｓｅｓ照射前
後における屈折率分布の均質度の変化を各々測定した。In addition, in the KrF excimer laser resistance evaluation, the energy density per pulse was 400mJ/err! , p,
While continuously irradiating at 100 Hz, the change in transmittance of 58 eV (approximately 215 nm) over time was measured using a transmittance meter to detect the E' center absorption band, and the internal transmittance of each sample decreased by 1%. In order to evaluate the number of irradiation pulses until the irradiation and the homogeneity of the refractive index, changes in the degree of homogeneity of the refractive index distribution were measured before and after irradiation with the irradiation pulse I x 106 Pulses in the 30φ area.
そして前記測定結果を表１及び表２に示す。The measurement results are shown in Tables 1 and 2.
その結果、前記サンプルのうち、アルゴン及びヘリウム
雰囲気下でＨＩＰ処理したものは、いずれも内部透過率
の低下も屈折率変化の均質性のいずれについても経時変
化が実質的になく好ましい耐ＫｒＦエキシマレーザ性を
得ると共に、その酸素ガス放出量はいずれも略Ｉ Ｘ
１０” （ｍｏｌｅｃｕｌｅｓ／ｒｒｆ）以下であった
。（Ｎｏ、１．２）
又ヘリウム１００％雰囲気で常圧下で熱処理を行ったも
のについては経時変化は多少存在するが。As a result, among the above samples, those subjected to HIP treatment in an argon and helium atmosphere showed no substantial change over time in either the internal transmittance decrease or the homogeneity of the refractive index change, making them resistant to KrF excimer lasers. At the same time, the amount of oxygen gas released is approximately I
10" (molecules/rrf) or less. (No. 1.2) Also, for those subjected to heat treatment under normal pressure in a 100% helium atmosphere, there are some changes over time.
熱処理を行わなかったものに比較して数段耐レーザ性が
若干向上している事が確認された。 （Ｎｏ、４）一方
大気と同一組成の酸素２０％チッ素８０％の雰囲気下で
ＨＩＰ処理したものについては、内部透過率屈折率の均
質性のいずれも大幅に悪化しくＮｏ。It was confirmed that the laser resistance was slightly improved by several steps compared to the one that was not heat treated. (No, 4) On the other hand, for the HIP treatment in an atmosphere of 20% oxygen and 80% nitrogen, which has the same composition as the atmosphere, both the internal transmittance and refractive index homogeneity were significantly deteriorated.
３）、又大気雰囲気で常圧下で熱処理を行ったものにつ
いてはＮ０９３程ではないが耐レーザ性が悪化している
ことが理解される。（Ｎｏ、５）従って前記実験結果よ
り酸素ガス放出量、即ちシリカガラス体中の酸素ガス含
有量と耐レーザ性は逆相関関係にあることが確認された
。3) It is also understood that the laser resistance of those subjected to heat treatment under atmospheric pressure under normal pressure is deteriorated, although not as much as N093. (No. 5) Therefore, from the above experimental results, it was confirmed that there is an inverse correlation between the amount of oxygen gas released, that is, the oxygen gas content in the silica glass body, and the laser resistance.
次に、本発明者は、シリカガラス中のＯＨ基量が耐紫外
線レーザ性にいかなる影響を与えるかを調べるために、
前記実施例と同様に高純度四塩化ケイ素原料を準備した
後、ＣＶＤスート再溶融法（スート法）にて、ＯＨ基量
を３重量Ｉ）Ｉ）０１以下、略１０ｗｔ、 ｐｐｍ、略
２２０ｗｔ、Ｉ）Ｉ）Ｉｎ含有する高純度シリカガラス
塊を合成し、 該ガラス塊を切断、研削加工して直径５
０Ｘｔ２０ｍｍの試験片を作成した後、前記と同様な脱
ガス処理−室温冷却を行った。Next, the present inventors investigated how the amount of OH groups in silica glass affects ultraviolet laser resistance.
After preparing a high-purity silicon tetrachloride raw material in the same manner as in the above example, the amount of OH groups was reduced to 3 weight I) I) 01 or less, approximately 10 wt, ppm, approximately 220 wt, using the CVD soot remelting method (soot method). I) I) Synthesize a high-purity silica glass lump containing In, cut and grind the glass lump to a diameter of 5
After creating a test piece of 0×t20 mm, it was subjected to the same degassing treatment and room temperature cooling as described above.
そして前記試験片をＨＩＰ処理法により、アルゴンガス
１００％雰囲気で、１０００℃、２０００ａｔｍ２０ｈ
ｒｓの処理を行なったもの（Ｎｏ、 ７．８．９）につ
いて、前記実施例と同様にＫｒＦエキシマレーザを照射
して、内部透過率の低下と屈折率変化の均質性の経時変
化について測定したところ、ＯＨ基に付いても相関があ
り、３重量１）１）ｍ以下の試験片Ｎｏ、 ７の耐レー
ザ性については、好ましい結果が得られなかった。Then, the test piece was subjected to HIP treatment at 1000°C and 2000 atm for 20 hours in a 100% argon gas atmosphere.
The sample that had been subjected to the rs treatment (No. 7.8.9) was irradiated with a KrF excimer laser in the same manner as in the above example, and the decrease in internal transmittance and the change over time in the homogeneity of the refractive index change were measured. However, there is also a correlation with respect to the OH groups, and favorable results were not obtained regarding the laser resistance of test piece No. 7 with a weight of 3.1) 1) m or less.
尚、前記角サンプルについて、原子吸光光度法及び中性
子放射化分析法によって、不純物分析を行なったところ
Ｌｉ、Ｎａ、にの合計が１５０ｗｔ、ｐｐｂ以下、Ｍｇ
、Ｃａの合計が１００ｗｔ、ｐｐｂ以下、Ｔｉ、 Ｃｒ
、 Ｆｅ、 Ｎｉ、 Ｃｕの合計が５０ｗｔ、 ｐｐｂ
以下であり、各種加熱処理によっても高純度が保持され
ていた。In addition, impurity analysis was performed on the corner sample by atomic absorption spectrometry and neutron activation analysis, and the total of Li, Na, and less than 150wt, ppb, and Mg
, total Ca is 100wt, ppb or less, Ti, Cr
, total of Fe, Ni, Cu is 50wt, ppb
The purity was maintained even after various heat treatments.
又比較供試体として、三軸方向より強い原理が認められ
かつ、屈折率変動幅（Δｎ）１ｘ１０−ｓの５ＵＰＲＡ
Ｓ ＩＬ−Ｐ２Ｏを出発母材として、Ａｒガス１００％
、１０００℃、２０００ａｔｍの条件にてＨＩＰ処理を
行った結果、屈折率の均質性の面で光学部材としては使
えるものは得られなかった。In addition, as a comparison specimen, a 5UPRA with a refractive index variation width (Δn) of 1x10-s was used, which was recognized to have a stronger principle than in the triaxial direction.
S IL-P2O as starting material, Ar gas 100%
As a result of performing HIP treatment under the conditions of , 1000° C. and 2000 atm, no material usable as an optical member was obtained in terms of homogeneity of refractive index.
「発明の効果」
以上記載したように、本発明によれば、紫外線レーザを
長時間照射した場合においても光学特性も屈折率の均質
性も劣化する事なく、耐レーザ性と高透過率を保証し得
る紫外線レーザ用光学部材を得る事が出来る。"Effects of the Invention" As described above, according to the present invention, even when irradiated with ultraviolet laser for a long time, neither the optical properties nor the homogeneity of the refractive index deteriorate, and laser resistance and high transmittance are guaranteed. Thus, it is possible to obtain an optical member for an ultraviolet laser that can be used.
等の種々の著効を有す。It has various effects such as
Claims (1)
質の合成シリカガラス体からなり、該ガラス体中に含有
するＯ＿２ガスを実質的に除去したことを特徴とする紫
外線レーザ用光学部材。 ２）前記ガラス体中のＯ＿２含有量を、真空中１０００
℃昇温時における酸素分子放出量換算で、略２×１０＾
１＾８（ｍｏｌｅｃｕｌｅｓ／ｍ＾２）以下に設定した
請求項１）記載の紫外線レーザ用光学部材。 ３）前記高均質の合成シリカガラス体が、三軸方向の脈
理が除去され且つ屈折率変動幅（Δｎ）を２×１０＾−
＾６以下に設定したガラス体である請求項１）記載の紫
外線レーザ用光学部材。 ４）前記前記高均質の合成シリカガラス体が、Ｌｉ、Ｎ
ａ及びＫからなるアルカリ金属含有量を１５０ｐｐｂ以
下、Ｍｇ及びＣａからなるアルカリ土類金属含有量を１
００ｐｐｂ以下、Ｔｉ、Ｃｒ、Ｆｅ、Ｎｉ及びＣｕの遷
移金属含有量を５０ｐｐｂ以下に設定したガラス体であ
る事を特徴とする請求項１）記載の紫外線レーザ用光学
部材。 ５）前記高純度高均質の合成シリカガラス体を不活性ガ
ス雰囲気下で且つ熱間等方圧加圧法（ＨＩＰ）処理にて
所定時間維持させる事により、該ガラス体中に含有する
Ｏ＿２を実質的に除去した事を特徴とする請求項１）記
載の紫外線レーザ用光学部材。 ６）前記ガラス体に照射される紫外線レーザが、ＫｒＦ
若しくはＡｒＦエキシマレーザ又はＹＡＧ４倍高調波（
略２５０ｎｍ）レーザ光である請求項１）記載の紫外線
レーザ用光学部材。[Claims] 1) It is characterized by being made of a highly pure and highly homogeneous synthetic silica glass body containing 10 weight ppm or more of OH groups, and having substantially removed O_2 gas contained in the glass body. Optical components for ultraviolet lasers. 2) The O_2 content in the glass body was adjusted to 1000% in vacuum.
Approximately 2 x 10^ in terms of the amount of oxygen molecules released when the temperature rises to ℃
The optical member for an ultraviolet laser according to claim 1, wherein the optical member is set to 1^8 (molecules/m^2) or less. 3) The highly homogeneous synthetic silica glass body has triaxial striae removed and has a refractive index fluctuation width (Δn) of 2×10^-
The optical member for an ultraviolet laser according to claim 1, which is a glass body having an irradiance of ^6 or less. 4) The highly homogeneous synthetic silica glass body contains Li, N
The alkali metal content consisting of a and K is 150 ppb or less, and the alkaline earth metal content consisting of Mg and Ca is 1
2. The optical member for an ultraviolet laser according to claim 1, wherein the glass body has a transition metal content of Ti, Cr, Fe, Ni, and Cu set to 50 ppb or less. 5) By maintaining the high-purity, highly homogeneous synthetic silica glass body under an inert gas atmosphere and using hot isostatic pressing (HIP) treatment for a predetermined period of time, the O_2 contained in the glass body is substantially removed. 2. The optical member for an ultraviolet laser according to claim 1, wherein the optical member is completely removed. 6) The ultraviolet laser irradiated to the glass body
Or ArF excimer laser or YAG 4th harmonic (
The optical member for an ultraviolet laser according to claim 1, wherein the optical member is a laser beam having a wavelength of approximately 250 nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2210252A JPH0829960B2 (en) | 1990-08-10 | 1990-08-10 | Ultraviolet laser optical components |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2210252A JPH0829960B2 (en) | 1990-08-10 | 1990-08-10 | Ultraviolet laser optical components |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0497922A true JPH0497922A (en) | 1992-03-30 |
| JPH0829960B2 JPH0829960B2 (en) | 1996-03-27 |
Family
ID=16586304
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2210252A Expired - Fee Related JPH0829960B2 (en) | 1990-08-10 | 1990-08-10 | Ultraviolet laser optical components |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0829960B2 (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09512384A (en) * | 1995-02-21 | 1997-12-09 | ゼネラル・エレクトリック・カンパニイ | Sodium halide discharge lamp |
| US6376401B1 (en) | 1998-09-07 | 2002-04-23 | Tosoh Corporation | Ultraviolet ray-transparent optical glass material and method of producing same |
| DE10308466A1 (en) * | 2003-02-21 | 2004-09-02 | Carl Zeiss Smt Ag | Producing quartz glass material used in microlithography-projection devices comprises minimizing the amount of peroxide defects in the material |
| WO2005105685A1 (en) * | 2004-04-28 | 2005-11-10 | Asahi Glass Company, Limited | Optical member made of synthetic quartz glass, and process for its production |
| US7934390B2 (en) | 2006-05-17 | 2011-05-03 | Carl Zeiss Smt Gmbh | Method for manufacturing a lens of synthetic quartz glass with increased H2 content |
| WO2011052610A1 (en) | 2009-10-30 | 2011-05-05 | 旭硝子株式会社 | Optical member for deep ultraviolet and process for producing same |
| WO2018198774A1 (en) | 2017-04-26 | 2018-11-01 | 東ソ－・エスジ－エム株式会社 | Ultraviolet-resistant quartz glass and method for manufacturing same |
| KR20190135013A (en) | 2017-04-26 | 2019-12-05 | 토소 에스지엠 가부시키가이샤 | UV-resistant quartz glass and its manufacturing method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6275604A (en) * | 1985-09-30 | 1987-04-07 | Mitsubishi Metal Corp | Light transmitting line having resistance to radiant rays |
| JPH0280343A (en) * | 1988-09-14 | 1990-03-20 | Shin Etsu Chem Co Ltd | Ultraviolet light resistant synthetic quartz glass and production thereof |
| JPH02124739A (en) * | 1988-10-31 | 1990-05-14 | Shin Etsu Chem Co Ltd | Synthetic quartz glass and its production |
-
1990
- 1990-08-10 JP JP2210252A patent/JPH0829960B2/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6275604A (en) * | 1985-09-30 | 1987-04-07 | Mitsubishi Metal Corp | Light transmitting line having resistance to radiant rays |
| JPH0280343A (en) * | 1988-09-14 | 1990-03-20 | Shin Etsu Chem Co Ltd | Ultraviolet light resistant synthetic quartz glass and production thereof |
| JPH02124739A (en) * | 1988-10-31 | 1990-05-14 | Shin Etsu Chem Co Ltd | Synthetic quartz glass and its production |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09512384A (en) * | 1995-02-21 | 1997-12-09 | ゼネラル・エレクトリック・カンパニイ | Sodium halide discharge lamp |
| US6376401B1 (en) | 1998-09-07 | 2002-04-23 | Tosoh Corporation | Ultraviolet ray-transparent optical glass material and method of producing same |
| DE10308466A1 (en) * | 2003-02-21 | 2004-09-02 | Carl Zeiss Smt Ag | Producing quartz glass material used in microlithography-projection devices comprises minimizing the amount of peroxide defects in the material |
| WO2005105685A1 (en) * | 2004-04-28 | 2005-11-10 | Asahi Glass Company, Limited | Optical member made of synthetic quartz glass, and process for its production |
| US7784307B2 (en) | 2004-04-28 | 2010-08-31 | Asahi Glass Company, Limited | Optical member made of synthetic quartz glass, and process for its production |
| US7934390B2 (en) | 2006-05-17 | 2011-05-03 | Carl Zeiss Smt Gmbh | Method for manufacturing a lens of synthetic quartz glass with increased H2 content |
| WO2011052610A1 (en) | 2009-10-30 | 2011-05-05 | 旭硝子株式会社 | Optical member for deep ultraviolet and process for producing same |
| US8541326B2 (en) | 2009-10-30 | 2013-09-24 | Asahi Glass Company, Limited | Optical member for deep ultraviolet and process for producing same |
| WO2018198774A1 (en) | 2017-04-26 | 2018-11-01 | 東ソ－・エスジ－エム株式会社 | Ultraviolet-resistant quartz glass and method for manufacturing same |
| KR20190135013A (en) | 2017-04-26 | 2019-12-05 | 토소 에스지엠 가부시키가이샤 | UV-resistant quartz glass and its manufacturing method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0829960B2 (en) | 1996-03-27 |
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