JPH04101476A - Laser device - Google Patents
Laser deviceInfo
- Publication number
- JPH04101476A JPH04101476A JP21960490A JP21960490A JPH04101476A JP H04101476 A JPH04101476 A JP H04101476A JP 21960490 A JP21960490 A JP 21960490A JP 21960490 A JP21960490 A JP 21960490A JP H04101476 A JPH04101476 A JP H04101476A
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- electric field
- width
- laser
- laser device
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- 238000012545 processing Methods 0.000 description 6
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- 230000008713 feedback mechanism Effects 0.000 description 2
- 229910052736 halogen Inorganic materials 0.000 description 2
- 150000002367 halogens Chemical class 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 2
- 229910052753 mercury Inorganic materials 0.000 description 2
- 230000002040 relaxant effect Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
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- 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 1
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- 238000002474 experimental method Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
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Landscapes
- Lasers (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、材料加工、投影露光用等の光源に用いる放電
励起型のレーザ装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a discharge-excited laser device used as a light source for material processing, projection exposure, and the like.
放電励起型のレーザ装置はマーキング、切断、溶接など
の材料加工に用いられるほか大規模集積回路（ＬＳＩ）
の回路パターンの製作のため光りソグラフィ用光源とし
て用いられる。Discharge-excited laser devices are used for material processing such as marking, cutting, and welding, as well as for large-scale integrated circuits (LSI).
It is used as a light source for optical lithography to produce circuit patterns.
月料加工用としてはＣＯ２、エキシマレーザなどが用い
られる。また光りソグラフィには主に縮小投影法か使わ
れており、この縮小投影法では照明光源により照らされ
た原画（レチクル）パタンの透過光を縮小投影光学系に
より半導体基板上の光感光性物質に投影して回路パター
ンを形成する。この投影像の分解能は用いられる光源の
波長で制限される。そこで、分解能を向上させるため光
源の波長は可視領域から紫外領域へと近年次第に短波長
化してきている。従来、紫外領域の光源として高圧水銀
ランプから発生ずるｇ線（波長４５３ｎｍ）、ｉ線（波
長３６５ ｎ ｍ）が使用されていた。しかし最小パタ
ーンの線幅が６４ＭＢで要求される０、２５μｍ以下と
なると、ｉ線ですでに短波長化としてはそろそろ限界に
来ている。CO2, excimer laser, etc. are used for monthly processing. In addition, the reduction projection method is mainly used in optical lithography, and in this reduction projection method, the transmitted light of the original image (reticle) pattern illuminated by the illumination light source is applied to the photosensitive material on the semiconductor substrate using the reduction projection optical system. Project it to form a circuit pattern. The resolution of this projected image is limited by the wavelength of the light source used. Therefore, in order to improve the resolution, the wavelength of the light source has been gradually shortened in recent years from the visible region to the ultraviolet region. Conventionally, G-lines (wavelength: 453 nm) and i-lines (wavelength: 365 nm) generated from high-pressure mercury lamps have been used as light sources in the ultraviolet region. However, when the line width of the minimum pattern becomes 0.25 μm or less, which is required for 64 MB, the i-line has already reached its limit for shortening the wavelength.
この技術的限界を解決するものとして深紫外（Ｄｅｅｐ
Ｕｌｔｒａ Ｖｉｏｌｅｔ；以下Ｄｅｅｐ−ＵＶ
という）レーザ光源が有望視されている。Deep ultraviolet (Deep UV)
Ultra Violet; hereinafter referred to as Deep-UV
) laser light sources are seen as promising.
特にエキシマレーザは高出力、高効率であり、媒質ガス
の組成によりＫｒＦ （波長２４６ｎｍ）、ＡｒＦ （
波長］、９３ｎｍ）なとの短波長で強い発振を得ること
ができる。上記Ｄｅｅｐ−ＵＶ領域では縮小投影レンズ
系を構成するガラス、結晶材料が非常に制約されるため
水銀ランプを用いた縮小投影レンズ系で用いられてきた
色収差補正が困難となる。そこで、レンズ系を色収差補
正する替りにレーザ共振器内にエタロン等の波長選択素
子を配没し、出力光のスペクトル幅をレンズ祠の色収差
が無視できる程度まで小さくすることにしている。この
方法で自然発振の場合にスペクトル幅て数ｎｍあった出
力を数ｐｍまで細く狭帯域化することかできる。In particular, excimer lasers have high output and high efficiency, and depending on the composition of the medium gas, KrF (wavelength 246 nm), ArF (
Strong oscillation can be obtained at short wavelengths such as 93 nm). In the deep-UV region, the glass and crystal materials constituting the reduction projection lens system are extremely restricted, making it difficult to correct chromatic aberration, which has been used in reduction projection lens systems using mercury lamps. Therefore, instead of correcting the chromatic aberration of the lens system, a wavelength selection element such as an etalon is placed inside the laser resonator to reduce the spectral width of the output light to the extent that the chromatic aberration of the lens can be ignored. With this method, the output spectrum width, which was several nanometers in the case of spontaneous oscillation, can be narrowed down to several nanometers.
こうした狭帯域エキシマレーザは放電励起型のレーザ装
置であり、第１２図に示すようにレーザチャンバ］内に
ＫｒＦ等のレーザガスを満たして、このレーザガスをレ
ーザチャンバ１の長手方向に沿って上下に配設された電
極６．７によって放電、励起してレーザ発振を行う。図
面において破線で囲まれた部分１１は放電励起領域であ
る。放電に伴い電極６．７の対向面６ａ、７ａが消耗し
、放電輪ＷＡが変化する。それとともに出力レーザ光４
のビーム幅が変化する。これはビーム幅の安定化という
点て問題となる。なお、同図において同図（ｂ）は同図
（ａ）のＣ−Ｃ断面図、同図（Ｃ）は同図（ａ）の縦断
面図である。加工用として使用する場合、このレーザの
ビーム幅の変化は横モトを劣化させ、ビームの集光性を
変化させたり、出力の変化を引き起こし、実用上問題と
なる。特に光リソグラフイ用の光源として使う場合には
このビーム幅の変化は狭帯域エキシマレーザの実用上以
下のような不都合を招来する。Such a narrow band excimer laser is a discharge excitation type laser device, and as shown in FIG. Laser oscillation is performed by discharging and exciting the electrodes 6 and 7 provided. A portion 11 surrounded by a broken line in the drawing is a discharge excitation region. As discharge occurs, the opposing surfaces 6a and 7a of the electrodes 6.7 are worn out, and the discharge ring WA changes. At the same time, the output laser beam 4
beam width changes. This poses a problem in terms of stabilizing the beam width. In addition, in the same figure, the same figure (b) is a CC sectional view of the same figure (a), and the same figure (C) is a longitudinal sectional view of the same figure (a). When used for processing, changes in the beam width of this laser deteriorate the lateral width, change the beam focusing ability, and cause changes in output, which poses a practical problem. In particular, when used as a light source for optical lithography, this change in beam width causes the following practical disadvantages of narrowband excimer lasers.
すなわち、狭帯域化に用いる波長選択素子は角度分散特
性を持つことはよく知られている。たとえば波長選択素
子として回折格子を使った場合はスペクトル幅を小さく
するため高い次数の回折を用いるため、動作点での角度
分散が大きくレーザの発散角がそのままスペクトル幅に
影響を及ぼす。That is, it is well known that the wavelength selection element used for band narrowing has angular dispersion characteristics. For example, when a diffraction grating is used as a wavelength selection element, high-order diffraction is used to reduce the spectral width, so the angular dispersion at the operating point is large and the divergence angle of the laser directly affects the spectral width.
すなわち発散角が大きいとスペクトル幅も広かってしま
うという性質を持つ。したがって放電幅が変化し、利得
領域が変化した場合レーザ光のビムダイバージェンスが
変化するためにスペクトル幅も大きく変化する。この変
動を回避するために従来アパーチュア８（第１２図（ａ
））を配設し、利得幅の安定化を図るようにしていた。In other words, it has the property that the larger the divergence angle, the wider the spectral width. Therefore, when the discharge width changes and the gain region changes, the beam divergence of the laser light changes, so the spectral width also changes significantly. In order to avoid this fluctuation, the conventional aperture 8 (Fig. 12(a)
)) to stabilize the gain range.
しかし、従来使用されていたいわゆるＣｈａｎｇ型電極
等では電極消耗時に出力を増加する際に不可避的に放電
幅が大きく増加するためアパーチュア８による利得制限
は出力の制御を困難としていた。However, with conventionally used so-called Chang-type electrodes, the discharge width inevitably increases greatly when increasing the output when the electrode wears out, so the gain restriction by the aperture 8 makes it difficult to control the output.
ここで放電幅が広がるメカニズムについて説明する。な
お、以下、電極は第１２図（ｂ）に示すＣ−Ｃ断面で表
すものとする。放電現象を説明する巨視的現象論として
はタウンゼント理論が知られており、放電現象を理解す
る」二で有用である。Here, the mechanism by which the discharge width widens will be explained. Hereinafter, the electrode will be represented by a cross section taken along the line C--C shown in FIG. 12(b). Townsend's theory is known as a macroscopic phenomenology that explains discharge phenomena, and is useful for understanding discharge phenomena.
この理論によればエキシマレーザに用いられるハロゲン
ガスを含む気体は負性ガスと呼ばれ、ハロゲンの大きな
電子親和力により放電中の電子の衝突電離（電離係数：
α）で生成された電子を捕捉しく電子付着係数：η）、
見掛上の電離係数（αη）を小さくし、放電を集中させ
やすくしている。これらの各係数と電界強度Ｅの関係を
第１３図に示す。なお、Ｐは規格化のための定数である
。According to this theory, the gas containing halogen gas used in excimer lasers is called a negative gas, and due to the large electron affinity of halogen, the impact ionization of electrons during discharge (ionization coefficient:
To capture the electrons generated by α), the electron attachment coefficient: η),
The apparent ionization coefficient (αη) is reduced, making it easier to concentrate the discharge. The relationship between each of these coefficients and the electric field strength E is shown in FIG. Note that P is a constant for normalization.
第１３図から明らかなように電離係数αは電界強度Ｅに
強く依存して、電子付着係数ηはほとんど電界強度Ｅに
依存しないため見掛上の電離係数（α−η）はある電界
強度Ｅ以上で急激に大きくなり、電界強度Ｅに大きく依
存する。すなわち、電極の表面上の電界強度分布に応じ
て放電を駆動するパラメータ（α−η）が変化するため
放電幅が電極表面での電界強度分布の影響を大きく受け
る。このため、放電幅を確保するためには放電励起型の
レーザ装置の電極形状として電極幅方向に均一となる電
界強度領域を大きくとれる形状にする必要がある。従来
は理想的な条件における電界計算の解析解をもとにＣｈ
ａｎｇ、変形Ｃｈａｎｇ型電極なとの形状が採用されて
きた。As is clear from FIG. 13, the ionization coefficient α strongly depends on the electric field strength E, and the electron attachment coefficient η hardly depends on the electric field strength E. Therefore, the apparent ionization coefficient (α−η) is Above this value, it increases rapidly and depends largely on the electric field strength E. That is, since the parameter (α-η) for driving the discharge changes depending on the electric field intensity distribution on the surface of the electrode, the discharge width is greatly influenced by the electric field intensity distribution on the electrode surface. Therefore, in order to ensure the discharge width, the electrode shape of the discharge-excited laser device needs to be shaped so that it can have a large field strength region that is uniform in the electrode width direction. Conventionally, Ch.
ang and modified Chang-type electrodes have been adopted.
ここで第１４図（ａ）にＣｈａｎｇ型電極の場合の電界
計算の電位分布を示す。同図（ａ）においてＬ］・・・
は等電位線である。図から負高圧電位にあるカソード（
上側電極）６とアノード（下側電極）７の間の電位分布
はアノード７の載った金属板と、電流の戻り配線１０お
よび絶縁部祠９により大きく曲げられていることがわか
る。ずなわち、実際の構成ではこうした配線や絶縁のた
め電界は理想的なＣｈａｎｇ型電界からずれていること
がわかる。Here, FIG. 14(a) shows the potential distribution of the electric field calculation in the case of the Chang type electrode. In the same figure (a), L]...
are equipotential lines. From the figure, the cathode (
It can be seen that the potential distribution between the upper electrode (upper electrode) 6 and the anode (lower electrode) 7 is greatly bent by the metal plate on which the anode 7 is mounted, the current return wiring 10, and the insulating part shrine 9. That is, it can be seen that in the actual configuration, the electric field deviates from the ideal Chang type electric field due to such wiring and insulation.
第１４図（ｂ）にカソード電極６近傍の等電界強度線Ｌ
２・・・を、同図（ｃ）にカソード電極６の表面に沿っ
た電界強度の変化の様子を示す。電極上の電界強度は、
電極中心点（Ａ点）から］／３程度離間した領域内では
等電界強度線との交わりが少なくこの領域内で均一電界
となっている。ラインＬ３に示すように電極中心点Ａか
ら電極右端点（Ｂ点）に行くにしたかって電界強度は最
初非常に緩やかに上昇し、端点Ｂに近づくにつれて急激
に上昇する様子がわかる。また第１４図（ｄ）にアノー
ド電極７近傍の等電界強度線Ｌ４・・・を示し、同図（
ｅ）にアノード電極表面に沿った電界強度の変化の様子
を示す。中心点Ａの電界強度をＥｏとする。これら図に
示すように電極中心点（Ａ点）から最初の約４ ｍｍの
区間では電界強度が均一であり、その後電極の右端点（
Ｂ点）に行くにつれて緩やかに弱くなり１２ｍｍはど離
れた後急激に弱くなる様子がわかる（ラインＬ４、Ｌ５
参照）。これは前述のカソード′６の場合とは逆の傾向
になっている。放電は電極中央部で発生しているが、放
電の幅を制限している要因は中央部で電界強度が大きく
なっているアノード７側であると考えられる。Figure 14(b) shows the constant electric field strength line L near the cathode electrode 6.
2..., the change in electric field strength along the surface of the cathode electrode 6 is shown in FIG. 2(c). The electric field strength on the electrode is
In a region spaced about ]/3 from the center point of the electrode (point A), there are few intersections with the equal electric field intensity lines, and a uniform electric field is created within this region. As shown by line L3, it can be seen that the electric field strength increases very slowly at first as it goes from the electrode center point A to the right end point (point B) of the electrode, and then increases sharply as it approaches end point B. Further, FIG. 14(d) shows a constant electric field strength line L4 near the anode electrode 7, and the same figure (
Figure e) shows how the electric field strength changes along the anode electrode surface. Let Eo be the electric field strength at center point A. As shown in these figures, the electric field strength is uniform in the first 4 mm from the electrode center point (point A), and then from the right end point of the electrode (point A).
You can see that it gradually weakens as you go to point B), and suddenly weakens after 12mm away (lines L4 and L5).
reference). This trend is opposite to that of the cathode '6 described above. Although the discharge occurs at the center of the electrode, it is thought that the factor limiting the width of the discharge is the anode 7 side where the electric field strength is large at the center.
放電を開始してから１．Ｘ］、、０８シヨツト後に消耗
した電極の中央部分における形状を測定し、この形状測
定データを用いて、消耗した電極中央部における電界強
度分布をシミュレーション解析の手法により計算した。1. After starting discharge. X], 08 After the shot, the shape of the exhausted electrode at its central portion was measured, and using this shape measurement data, the electric field intensity distribution at the exhausted electrode's central portion was calculated by a simulation analysis method.
このシミュレーション結果を横軸を中心点Ａから右方向
に向かう離間距離、縦軸を中心点Ａの電界強度Ｅ。に列
する電界強度Ｅの変化率△Ｅ／Ｅとして第１５図に示す
。同図（ａ）はカソード６を、同図（ｂ）はアノード７
を示す。白丸印は放電開始前を、黒丸印は１×１０８シ
ョット後を示している。これら図からも明らかなように
１． Ｘ １．０８ショット後では消耗が進］０
行してスタート時よりも中央部分において均一電界部分
が広がっている。この均一電界部分の幅は観測されたビ
ーム幅とほぼ対応している。これは強電界である均一電
界部分に電流が集中し消耗が進み、結果的に広い均一電
界部分が形成されたものと考えられる。このように従来
の電極形状ではレーザ装置の運転が開始されると時間の
経過とともに電極が消耗して、均一電界部分が拡大され
これに応じて出力レーザ光のビーム幅が変動してしまう
ことになる。これは電極幅が放電幅よりも大きいという
ことに起因している。In this simulation result, the horizontal axis represents the distance to the right from the center point A, and the vertical axis represents the electric field strength E at the center point A. FIG. 15 shows the rate of change ΔE/E of the electric field strength E in the order of ΔE/E. The figure (a) shows the cathode 6, and the figure (b) shows the anode 7.
shows. White circles indicate before the start of discharge, and black circles indicate after 1×108 shots. As is clear from these figures, 1. X 1. Depletion progresses after 08 shots] 0 The uniform electric field part is wider in the center than at the start. The width of this uniform electric field portion roughly corresponds to the observed beam width. It is thought that this is because the current concentrates in the uniform electric field portion, which is a strong electric field, and the consumption progresses, resulting in the formation of a wide uniform electric field portion. In this way, with the conventional electrode shape, when the laser device starts operating, the electrode wears out over time, and the uniform electric field area expands, causing the beam width of the output laser light to fluctuate accordingly. Become. This is due to the fact that the electrode width is larger than the discharge width.
本発明はこうした実情に鑑みてなされたものであり、電
極消耗によるビーム幅の変動を少なくすることができる
レーザ装置を提供しようとするものである。The present invention has been made in view of these circumstances, and it is an object of the present invention to provide a laser device that can reduce variations in beam width due to electrode wear.
そこで本発明では、レーザチャンバの長手方向に沿って
上下に対向して配設された２つの電極間で放電を行い、
前記レーザチャンバ内のレーザガスを励起してレーザ光
を発生させるレーザ装置に］ ］
おいて、前記２つの電極のうち少なくとも一方の電極の
幅を放電幅と略一致させるとともに、前記少なくとも一
方の電極の長手方向に沿って該電極の左右両側に導電体
を配設している。Therefore, in the present invention, a discharge is generated between two electrodes arranged vertically facing each other along the longitudinal direction of the laser chamber.
In the laser device that excites a laser gas in the laser chamber to generate laser light, the width of at least one of the two electrodes is made substantially equal to the discharge width, and the width of at least one of the at least one electrode is Conductors are disposed on both left and right sides of the electrode along the longitudinal direction.
すなわち、かかる構成によれば、放電幅が電極幅の大き
さに応じた一定幅となる。このため出力レーザ光のビー
ム幅が一定となり、レーザ装置が安定して運転される。That is, according to this configuration, the discharge width becomes a constant width depending on the size of the electrode width. Therefore, the beam width of the output laser light is constant, and the laser device can be operated stably.
しかも電極の両側に配設された導電体によって電極の消
耗速度が小さく押さえられて電極からのコンタミネーシ
ョンが少なくなる。Furthermore, the conductors disposed on both sides of the electrode keep the rate of wear of the electrode to a low level, thereby reducing contamination from the electrode.
以下、図面を参照して本発明に係るレーザ装置の実施例
について説明する。実施例ではレーザ装置として狭帯域
発振エキシマレーザを想定している。実施例装置は先に
第１２図に示したものと基本的には同一構成のものであ
り、電極６．７の替りに後述する電極１２．１３を用い
ている。レーザチャンバ１内にはＫ ｒ Ｆ等のレーザ
ガスか満たされていて、このレーザガスをレーザチャン
バ１の長手方向に沿って上下に配設された電極１２（カ
ソード電極）、電極１３（アノード電極）によって放電
、励起してレーザ発振を行う。レーザ光はレーザチャン
バ］とフロントミラー２と波長選択素子であるグレーテ
ィング５とで構成された光共振器で共振され、フロント
ミラー２から有効なレーザ光４として出力される。グレ
ーティング５は発振光を狭帯域化するとともにリアミラ
ーとして機能するものであり、いわゆるリトロ−配置を
とっている。図面において破線で囲まれた部分１］は放
電励起領域であり、８はアパーチュア、９は絶縁部材、
１０はアノード電流戻り配線である。ＷＡは放電幅を示
す。電極］３はレーザチャンバ１の長手方向に垂直な断
面、つまり横断面の外郭ラインのうち電極１２に対向す
るラインを楕円状にしたことを特徴としている。さらに
同横断面において形状が円となる円柱状の電界緩和用の
金属構造物１４（以下、電界緩和電極という）を電極１
３の左右両側に配設したことを特徴としている。なお、
第１２図（ｂ）の矢視方向において右側のものを１４Ｒ
１左側のものを１４Ｌとする。Embodiments of the laser device according to the present invention will be described below with reference to the drawings. In the embodiment, a narrow band oscillation excimer laser is assumed as the laser device. The apparatus of this embodiment has basically the same structure as that shown in FIG. 12, and electrodes 12.13, which will be described later, are used in place of electrodes 6.7. The laser chamber 1 is filled with a laser gas such as K r F, and the laser gas is transferred by an electrode 12 (cathode electrode) and an electrode 13 (anode electrode) arranged vertically along the longitudinal direction of the laser chamber 1. Laser oscillation is performed by discharging and excitation. The laser beam resonates in an optical resonator constituted by a laser chamber], a front mirror 2, and a grating 5 which is a wavelength selection element, and is outputted from the front mirror 2 as an effective laser beam 4. The grating 5 narrows the band of the oscillated light and also functions as a rear mirror, and has a so-called retro arrangement. In the drawing, the part 1 surrounded by a broken line is a discharge excitation region, 8 is an aperture, 9 is an insulating member,
10 is an anode current return wiring. WA indicates discharge width. The electrode] 3 is characterized in that a cross section perpendicular to the longitudinal direction of the laser chamber 1, that is, a line facing the electrode 12 among the outer contour lines of the cross section is shaped like an ellipse. Further, a cylindrical electric field relaxation metal structure 14 (hereinafter referred to as an electric field relaxation electrode) having a circular shape in the same cross section is attached to the electrode 1.
It is characterized by being placed on both the left and right sides of 3. In addition,
14R on the right side in the direction of the arrow in Fig. 12(b)
1. Let the one on the left be 14L.
電極］２、］３の横断面は左右対称であり、したがって
レーザ装置運転中の電位分布は横断面中心軸に関して左
右対称である。そこで電極１２、］３の右側部分のみを
代表させて電位分布を第１図に示す。The cross sections of the electrodes ]2, ]3 are bilaterally symmetrical, and therefore the potential distribution during operation of the laser device is bilaterally symmetrical with respect to the central axis of the cross section. Therefore, the potential distribution is shown in FIG. 1, representing only the right side of the electrodes 12, ]3.
同図において上側は半径］−３ｍｍの円弧状の対向面１
２ａを持つカソード電極１２であり、下側は横方向電極
幅が８ ＋ｎｎ＋で、対向面１．３ ａが楕円状に形成
されたアノード電極］３である。この実施例では電極１
３の横幅が楕円の長径の長さと一致し、かつ電極］３の
左右中心軸が楕円の短径軸と一致するように形成されて
いる。これらカソード電極１２とアノード電極１３の電
極間隔は２５ｍｍであるものとする。すなわち電極］３
の横幅は電極間隔以下である。アノード電極１３の右脇
の電界緩和電極１．４ Ｒの横断面は直径８ｍｍの円で
あり、電極１３と電気的に接続されている。左側の電界
緩和電極１４ Ｌについても同様である。つまり電界］
４
緩和電極］４は電極１３の対向面に対して段差を設けて
その高さが電極］−３の高さよりも小さくなるように配
設されている。ここで電極１．２．１．３は放電を行う
ので、耐放電性に優れた高融点金属材料等を用いる必要
がある。一方、電界緩和電極］、４Ｒ（１４Ｌも）は放
電を行うことはなく静電的に電位を保持するたけでよ・
いので、必ずしも耐放電性に優れた高融点金属材料等を
用いる必要はなく、加工性に優れた電極１２、］−３の
材料とは異なる金属材料を用いることができる。In the same figure, the upper side is an arc-shaped opposing surface 1 with a radius of −3 mm.
2a, and the lower side is an anode electrode with a lateral electrode width of 8 +nn+ and an opposing surface 1.3a formed in an elliptical shape. In this example, electrode 1
The width of the electrode 3 is formed to match the length of the major axis of the ellipse, and the left-right center axis of the electrode 3 coincides with the minor axis of the ellipse. It is assumed that the electrode interval between the cathode electrode 12 and the anode electrode 13 is 25 mm. i.e. electrode] 3
The width of the electrode is less than or equal to the electrode spacing. The cross section of the electric field relaxation electrode 1.4R on the right side of the anode electrode 13 is a circle with a diameter of 8 mm, and is electrically connected to the electrode 13. The same applies to the left electric field relaxation electrode 14L. In other words, electric field]
4 Relaxation electrode] 4 is provided with a step on the opposite surface of electrode 13, and is arranged so that its height is smaller than the height of electrode]-3. Here, since the electrodes 1.2.1.3 perform discharge, it is necessary to use a high melting point metal material or the like having excellent discharge resistance. On the other hand, the electric field relaxation electrode], 4R (also 14L) does not discharge, but merely holds the potential electrostatically.
Therefore, it is not necessarily necessary to use a high melting point metal material with excellent discharge resistance, and a metal material different from the material of the electrode 12,]-3, which has excellent workability, can be used.
同図（ａ）はアノード電極１３の対向面１３ ａの楕円
の短長径比（ｒ＝短径／長径）がｒ＝ｉの場合、つまり
対向面１３ ａが円弧の場合のシミュレーション結果で
ある。また同図（ｂ）は短長径比ｒ＝２の場合、同図（
ｃ）は短長径比ｒ＝４の場合の各シミュレーション結果
である。なお、以下第８図までの図面において（ａ）、
（ｂ）および（Ｃ）はそれぞれ短長径比ｒ＝１．２およ
び４の各場合をそれぞれ示すものとする。FIG. 5A shows the simulation results when the ratio of minor axis to major axis (r=minor axis/major axis) of the ellipse of the opposing surface 13a of the anode electrode 13 is r=i, that is, when the opposing surface 13a is an arc. In addition, the same figure (b) shows the case where the minor axis ratio r=2, the same figure (
c) shows each simulation result when the minor axis ratio r=4. In addition, in the drawings up to Figure 8 below, (a),
(b) and (C) show the cases where the minor axis ratio r=1.2 and 4, respectively.
全体の等電位線の傾向は第１２図（ａ）に示す］ ５
従来のものと似ているが、アノード１３近傍の等電位線
が電界緩和電極１４Ｒにより押し上げられ電極上端部分
（中心軸部分）での電位傾度が緩やかになっている。こ
の様子はアノード１３近傍明大した第２図でよくわかる
。The tendency of the whole equipotential line is shown in FIG. 12(a)] 5. It is similar to the conventional one, but the equipotential line near the anode 13 is pushed up by the electric field relaxation electrode 14R, and the upper end part of the electrode (central axis part) The potential gradient at is gradual. This situation can be clearly seen in FIG. 2, where the vicinity of the anode 13 is clearly enlarged.
また第３図はアノード電極１３近傍の電界強度分布の詳
細を、第４図は電極１３表面での電界強度Ｅの変化の様
子をそれぞれ示す。（ａ）の真円の場合には電極１３の
中心点Ａで電界強度が強く、右端に行くに従い急激に弱
くなって尖った分布になっている。（ｂ）の楕円（短長
径比１：２）の場合には中心点Ａ近傍で（ａ）の場合よ
りも平坦な電界分布になっている。（Ｃ）の楕円（短長
径比１：４）の場合には逆に中心点Ａ近傍の電界強度が
小さくなり中央周辺部りで電界が強くなっている。Further, FIG. 3 shows details of the electric field intensity distribution near the anode electrode 13, and FIG. 4 shows changes in the electric field intensity E on the surface of the electrode 13. In the case of a perfect circle as shown in (a), the electric field strength is strong at the center point A of the electrode 13, and as it goes to the right end, it rapidly weakens, resulting in a sharp distribution. In the case of the ellipse shown in (b) (minor length axis ratio 1:2), the electric field distribution near the center point A is flatter than in the case of (a). In the case of the ellipse shown in (C) (minus/major axis ratio 1:4), on the contrary, the electric field strength near the center point A is small and the electric field is strong near the center.
ここで電界緩和電極１４を設けたことによる効果につい
て説明する。第５図、第６図は電界緩和電極］４が配設
されていない場合におけるアット電極］３近傍の電界強
度分布の詳細を示す図および電極１３表面における電界
強度Ｅの変化の様子を示す図である。これら第５、第６
図と第３、第４図との比較から明らかに電界緩和電極１
４を設けたことによりアノード電極１３の中央周辺部り
における電界が緩和、つまり中心点Ａと周辺部りにおけ
る電界の大きさの差が小さくなっていることがわかる。Here, the effect of providing the electric field relaxation electrode 14 will be explained. 5 and 6 are diagrams showing the details of the electric field strength distribution in the vicinity of the electric field relaxation electrode [at electrode in the case where the electric field relaxation electrode 4 is not provided] 3 and diagrams showing changes in the electric field strength E on the surface of the electrode 13. It is. These fifth and sixth
From the comparison between the figure and Figures 3 and 4, it is clear that the electric field relaxation electrode 1
4, the electric field at the center and periphery of the anode electrode 13 is relaxed, that is, the difference in the magnitude of the electric field between the center point A and the periphery becomes smaller.
さらにアノード電極１−３の上端部の電界強度の絶対値
をみると（ａ）、（ｂ）、（ｃ）の順で強く、楕円形状
が偏平になるにしたがって中心”ｔｌ Ａに電界強度は
小さくなり、周辺部りにおける電界が逆に強くなるのが
わかる。また、アノード電極１−３の中心点Ａにおける
電界強度は、電界緩和電極１４が配設された場合には、
配設されていない場合に比較して一様に小さくなってい
るのがわがる。Furthermore, looking at the absolute value of the electric field strength at the upper end of the anode electrode 1-3, it is strong in the order of (a), (b), and (c), and as the elliptical shape becomes flat, the electric field strength at the center "tlA" increases. It can be seen that the electric field becomes smaller, and the electric field at the periphery becomes stronger.Also, the electric field strength at the center point A of the anode electrode 1-3 is as follows when the electric field relaxation electrode 14 is provided.
It can be seen that the size is uniformly smaller than when it is not provided.
今、仮にレーザ装置の運転を開始すべくオペレタが操作
スイッチをオン側に投入して、（ｂ）の状態から放電が
始まったものとする。電界は対向面１３ａの中央部分の
広い範囲に渡りかなり均−であり、放電は電極］３の楕
円部分１３ ａ全面にわたり広がっているため電極］３
の消耗は電極楕円部分１３ａ全面にわたり同時に進行す
る。第４図（ｂ）かられかるように中心点Ａ近傍の電界
の強い領域に局所的に放電電流がより多く流れるためこ
の部分がより早く消耗する。やがて（ｃ）の状態に近づ
き中心点近傍の領域の電界が弱くなり消耗が少なくなる
。今度は中央周辺部りの電界が強まり、電界の強い周辺
部りに放電電流がより多く流れ、より早く消耗する。こ
うして再び（ｂ）の状態に戻る。こうして（ｂ）、（Ｃ
）の間のある安定な形状に放電部形状が落ち着くことと
なる。Now, assume that the operator turns on the operation switch to start operating the laser device, and discharge begins in the state shown in (b). The electric field is fairly uniform over a wide range in the center of the opposing surface 13a, and the discharge spreads over the entire elliptical part 13a of the electrode]3.
The wear progresses simultaneously over the entire surface of the electrode elliptical portion 13a. As can be seen from FIG. 4(b), more discharge current locally flows in the area where the electric field is strong near the center point A, so this area is consumed more quickly. Eventually, the state of (c) is approached, and the electric field in the area near the center point becomes weaker, resulting in less consumption. This time, the electric field in the center and periphery areas becomes stronger, and more discharge current flows in the periphery areas where the electric field is stronger, causing faster depletion. In this way, the state returns to state (b). Thus (b), (C
) The shape of the discharge portion settles into a stable shape between .
こうした一種の負のフィードバック機構による自己形状
維持機構が働くため均一電界を一定の領域において維持
することができ、放電幅ＷＡを変化させることなく長期
間安定に運転させることが可能となる。以上のことはシ
ミュレーション結果から明らかになった。Since this self-shape maintenance mechanism based on a kind of negative feedback mechanism works, a uniform electric field can be maintained in a certain region, and it becomes possible to operate stably for a long period of time without changing the discharge width WA. The above points were made clear from the simulation results.
実験的には短長径比ｒが小さいと電界強度Ｅが電極の中
心点Ａで強く、周辺部りに行くに従い急］ ８
激に弱くなるため放電は中央の狭い領域に集まる。Experimentally, when the short-to-long axis ratio r is small, the electric field strength E is strong at the center point A of the electrode, and becomes steeper toward the periphery.] 8 It becomes extremely weak, so that the discharge gathers in a narrow area at the center.
一方、短長径比ｒを増やし過ぎると中央周辺部りでの電
界強度Ｅが増加し、放電は電極の周辺部の部分に集中し
やすくなる。すなわち短長径比ｒには放電が一箇所に集
中しないある最適値が存在し、実験の場合には短長径比
ｒ ＝ ３とすると電極幅に渡り電界かほぼ均一となり
電極幅とほぼ同じ長さの放電幅ＷＡを得ることができた
。すなわち、こうした最適な短長径比ｒて電極１３の対
向面１３ａが形成され、レーザ運転が行われると放電は
ほぼ電極積内部分１．３ ａ全面にわたり広がるため消
耗は電極積内部分１３ ａ全面にわたり同時に進行する
。たとえ局所的に電界の強い部分があったとしてもそこ
に放電電流がより多く流れ、そこがより早く消耗する。On the other hand, if the short-major axis ratio r is increased too much, the electric field strength E at the center and periphery increases, and the discharge tends to concentrate at the periphery of the electrode. In other words, there is an optimum value for the short-major axis ratio r that prevents the discharge from concentrating in one place, and in the case of experiments, when the short-major axis ratio r = 3, the electric field is almost uniform over the electrode width, and the length is almost the same as the electrode width. It was possible to obtain a discharge width WA of . In other words, the opposing surface 13a of the electrode 13 is formed with such an optimal short-long axis ratio r, and when laser operation is performed, the discharge spreads over almost the entire area within the electrode area 1.3a, so that wear occurs over the entire area within the electrode area 13a. progress simultaneously across the board. Even if there is a locally strong electric field, more discharge current will flow there and the battery will be consumed more quickly.
やがてその部分の電界が弱くなり消耗が少なくなる一種
の負のフィードバック機構が働く。このため長期間均一
電界を電極幅で規定される領域において維持することが
でき、放電幅を一定にして運転させることが可能となる
。Eventually, the electric field in that area becomes weaker, causing a kind of negative feedback mechanism that reduces consumption. Therefore, a uniform electric field can be maintained for a long period of time in the region defined by the electrode width, and it is possible to operate with a constant discharge width.
ここて電界緩和電極１４を配設したことによる］９
利点について説明する。電界緩和電極１４が設けられて
いない場合には、アノード電極］３の表面における電界
強度が大きくなり、このため電極１３からのコンタミネ
ーションが多いという不都合があったが、電界緩和電極
１４を配設することによりこの点が改善された。さらに
電界緩和電極１４か設けられていない場合には、アノー
ド電極］３の表面における電界強度の分布の状態がアッ
ト電極］３の形状により大きく変わるため、特にレーザ
運転開始時に放電か不安定になる場合があったが、この
点も電界緩和電極１４を配設することにより改善された
。こうした実験上の所見は上記シミュレーション結果と
ほぼよい一致を示し、上記所見が妥当であることを示し
ている。[9] Advantages of arranging the electric field relaxation electrode 14 will now be explained. If the electric field relaxation electrode 14 was not provided, the electric field strength on the surface of the anode electrode 3 would be large, resulting in a large amount of contamination from the electrode 13.However, the electric field relaxation electrode 14 is provided. This point was improved by doing so. Furthermore, if the electric field relaxation electrode 14 is not provided, the electric field intensity distribution on the surface of the anode electrode 3 changes greatly depending on the shape of the at electrode 3, resulting in unstable discharge, especially at the start of laser operation. However, this point was also improved by providing the electric field relaxation electrode 14. These experimental findings show almost good agreement with the above simulation results, indicating that the above findings are valid.
この実施例では短長径比ｒ＝３で電極積内部分１、３
ａ全面において一定の電界を得て、電極幅と同じ大きさ
の放電幅ＷＡを得るようにしたが、この最適値の値は全
体の電極の幅、電極間間隔、幾何学的な配置、絶縁部の
誘電率、放電媒質ガスの性質で変化するため、状況に応
して最適値を求める必要がある。In this example, the ratio r=3 and the electrode product inner parts 1 and 3
A A constant electric field was obtained over the entire surface, and a discharge width WA of the same size as the electrode width was obtained. However, this optimum value depends on the overall electrode width, inter-electrode spacing, geometrical arrangement, and insulation. Since it changes depending on the dielectric constant of the part and the properties of the discharge medium gas, it is necessary to find the optimum value depending on the situation.
なお実施例では電界緩和電極］４の断面を円と（７たが
、本発明としてはこれに限定されることなくたとえば第
７図に示すように断面形状が］７４円となる電界緩和電
極１５てあってもよい。第７図、第８図は第３図、第４
図に相当するものであり、同等の効果を奏していること
がわかる。Note that in the embodiment, the cross section of the electric field relaxing electrode 4 is a circle (74), but the present invention is not limited to this; for example, as shown in FIG. Figures 7 and 8 may be compared to Figures 3 and 4.
It can be seen that this corresponds to the figure and has the same effect.
なお電界緩和電極の断面形状は実施例のものに限定され
ることなく、第９図（ａ）に示すように断面形状として
楕円と直線とを組み合わせたラインを有する電界緩和電
極］６、同図（ｂ）に示すように断面形状として円弧と
直線を組み合わせたラインを有する電界緩和電極１７て
あってもよい。Note that the cross-sectional shape of the electric field relaxation electrode is not limited to that of the example, and as shown in FIG. 9(a), the electric field relaxation electrode may have a cross-sectional shape that is a combination of an ellipse and a straight line. As shown in (b), the electric field relaxation electrode 17 may have a cross-sectional shape that is a combination of a circular arc and a straight line.
他に断面形状を楕円、スムースな関数系の曲線で形成す
ることが考えられる。いずれにせよ、直線と直線、また
は曲線と直線が接続する部分てそれらをスムーズにつな
げば電界集中が起こり難くなり、沿面放電や不要放電の
発生を防止することかできる。要は電界緩和電極として
は隣接する放電用の電極の両側に配設されるものであれ
ばよい。Another possibility is to form the cross-sectional shape with an ellipse or a smooth functional curve. In any case, if straight lines or curved lines are connected smoothly, electric field concentration will be less likely to occur, and creeping discharge and unnecessary discharge can be prevented. In short, it is sufficient that the electric field relaxing electrodes be disposed on both sides of adjacent discharge electrodes.
このように放電用の電極の両側に電界緩和電極すると、
電極交換時は、カソード電極およびアノード電極のみを
交換すればよく、電界緩和電極の交換は不要である。し
たがってアノード電極、カソード電極をそれぞれ単一部
材で構成した場合と比較すると、交換時のコスト、さら
には電極製作コスト低減の利点が得られる。When electric field relaxation electrodes are placed on both sides of the discharge electrode in this way,
When replacing the electrodes, it is only necessary to replace the cathode electrode and the anode electrode, and there is no need to replace the electric field relaxation electrode. Therefore, compared to a case in which the anode electrode and the cathode electrode are each made of a single member, there is an advantage in that the cost at the time of replacement and further the cost for manufacturing the electrodes can be reduced.
また実施例では片側のアノード電極１３のみについて電
極幅と同じ大きさの放電幅ＷＡを得るとともに、電界緩
和電極１４を設けるようにしたか、第１０図に示すよう
に両側の電極１．２−１３−について電極幅と同じ大き
さの放電幅ＷＡを得るように各電極の対向面を形成する
とともに、各電極それぞれに電界緩和電極１．４−１．
４を配設する実施も可能であり、実施例と同等の効果が
得られる。In addition, in the embodiment, a discharge width WA of the same size as the electrode width was obtained only for the anode electrode 13 on one side, and an electric field relaxation electrode 14 was provided, or as shown in FIG. 13-, the opposing surfaces of each electrode are formed so as to obtain a discharge width WA of the same size as the electrode width, and each electrode is provided with an electric field relaxation electrode 1.4-1.
4 is also possible, and the same effect as the embodiment can be obtained.
なお、電界緩和電極の材質としては導電性物質であれば
、金属、セラミック、プラスチックいずれても実施可能
である。また電界緩和電極は静電的に電位を保持するこ
とかできればよく、第１１図（ａ）に示すように電界緩
和電極１４の全部を絶縁性のチューブ１８で被覆する実
施も可能であり、同図（ｂ）に示すように一部を絶縁物
１９て被覆するとともに、電気的（容量、誘導、抵抗的
）に電極］３と接続させる実施も可能である。The material for the electric field relaxation electrode may be metal, ceramic, or plastic as long as it is conductive. Further, the electric field relaxation electrode only needs to be able to hold the potential electrostatically, and it is also possible to cover the entire electric field relaxation electrode 14 with an insulating tube 18 as shown in FIG. 11(a). As shown in Figure (b), it is also possible to cover a part with an insulator 19 and electrically (capacitively, inductively, resistively) connect it to the electrode 3.
なお実施例では放電用の電極の他に電界緩和電極を別途
用意し、これを放電用の電極の両側に隣接配置するよう
にしたが、これらを一体成型する実施もまた可能である
。In the embodiment, electric field relaxation electrodes were separately prepared in addition to the discharge electrodes, and these electrodes were arranged adjacent to both sides of the discharge electrodes, but it is also possible to integrally mold these electrodes.
以上説明したように本発明によれば放電励起型のレーザ
装置を長期間にわたり放電幅を変化させることなく安定
に運転することが可能となる。したがって材料加工に木
し−サ装置を使用すれば、長期にわたり安定で、ビーム
幅、横モードの変化のない安定な材料加工が可能であり
、実用」二きわめて有用である。また本し−サ装置の共
振器内部あるいはその一部に波長選択素子を用いること
てスペクトル幅の変動が極めて小さい狭帯域発振レーザ
を実現することができ、従来レーザリソグラフィの課題
となっていた発振スペクトル幅の長期間安定化を可能と
し実用」二極めて有用である。As explained above, according to the present invention, it is possible to stably operate a discharge-excited laser device over a long period of time without changing the discharge width. Therefore, if a wood cutting machine is used for material processing, it is possible to perform stable material processing over a long period of time without changes in beam width or transverse mode, which is extremely useful in practice. In addition, by using a wavelength selection element inside or a part of the resonator of this laser device, it is possible to realize a narrowband oscillation laser with extremely small fluctuations in spectral width, which has been an issue in conventional laser lithography. It is extremely useful in practical applications because it enables long-term stabilization of the spectral width.
第１図は本発明に係るレーザ装置の実施例装置で使用さ
れる電極の近辺における等電位線の分布の様子を示す図
、第２図は第１図に示すアノード電極近傍の等電位線の
分布の様子を示す図、第３図は第１図に示すアノード電
極近傍の電界強度の分布の様子を示す図、第４図は第３
図に示すアット電極の対向面における電界強度の変化の
様子を示す図、第５図は電界緩和電極が配設されていな
い場合のアノード電極近傍の電界強度の分布の様子を示
す図、第６図は第５図に示すアノード電極の対向面にお
ける電界強度の変化の様子を示す図、第７図は電界緩和
電極の断面形状が人なる場合のアノード電極近傍の電界
強度の分布の様子を示す図、第８図は第７図に示すアノ
ード電極の対向面における電界強度の変化の様子を示す
図、第９図は他の実施例における電界緩和電極の形状を
示す図、第１０図は対向する画電極に本発明を適用した
場合の断面の様子を示す図、第、１１図は電界緩和電極
を絶縁性被膜で被覆した実施例を示す図、第１２図は従
来のレーザ装置の全体構成を示す図、第１３図はエキシ
マレーザガス放電中の電離係数、付着係数、見掛けの電
離係数の電界強度依存性を示すグラフ、第１４図（ａ）
、（ｂ）、（ｃ）、（ｄ）および（ｅ）はそれぞれ従来
技術における電極を用いた場合の画電極近傍の電位分布
、カソード電極近傍における電界強度分布、カソード電
極の対向面における電界強度の変化、アノード電極近傍
における電界強度分布、アノード電極の対向面における
電界強度の変化を示す図、第１５図は従来技術の電極を
用いた場合のレーザ運転前後における電極表面の電界強
度の変化率を示すグラフである。
１・・レーザチャンバ、２・・フロントミラー、４・・
レーザ光、５・・グレーティング、１２・・カソード電
極、］３・・・アノード電極、１−４、］４−１５．１
６．１７・・電界緩和電極。
ぐａ）
（ｂ）
７５Ｆ？
第
図FIG. 1 is a diagram showing the distribution of equipotential lines near the electrodes used in the embodiment of the laser device according to the present invention, and FIG. 2 is a diagram showing the distribution of equipotential lines near the anode electrode shown in FIG. 1. Figure 3 is a diagram showing the distribution of the electric field strength near the anode electrode shown in Figure 1.
Figure 5 is a diagram showing how the electric field strength changes on the opposing surface of the at electrode shown in Figure 5. Figure 5 is a diagram showing the distribution of electric field strength near the anode electrode when no electric field relaxation electrode is provided. The figure shows how the electric field intensity changes on the opposing surface of the anode electrode shown in Fig. 5, and Fig. 7 shows the electric field intensity distribution near the anode electrode when the cross-sectional shape of the electric field relaxation electrode is human. 8 is a diagram showing how the electric field intensity changes on the opposing surface of the anode electrode shown in FIG. 7, FIG. 9 is a diagram showing the shape of the electric field relaxation electrode in another embodiment, and FIG. 11 is a diagram showing an embodiment in which the electric field relaxation electrode is covered with an insulating film, and FIG. 12 is the overall configuration of a conventional laser device. Figure 13 is a graph showing the electric field strength dependence of the ionization coefficient, adhesion coefficient, and apparent ionization coefficient during excimer laser gas discharge, Figure 14 (a)
, (b), (c), (d), and (e) are the potential distribution near the picture electrode, the electric field intensity distribution near the cathode electrode, and the electric field intensity on the opposite surface of the cathode electrode when using electrodes in the prior art, respectively. Fig. 15 shows the change in electric field intensity on the electrode surface before and after laser operation when using the conventional electrode. This is a graph showing. 1...Laser chamber, 2...Front mirror, 4...
Laser light, 5... Grating, 12... Cathode electrode, ]3... Anode electrode, 1-4, ]4-15.1
6.17...Electric field relaxation electrode. Gua) (b) 75F? Diagram
Claims (10)
て配設された２つの電極間で放電を行い、前記レーザチ
ャンバ内のレーザガスを励起してレーザ光を発生させる
レーザ装置において、 前記２つの電極のうち少なくとも一方の電極の幅を放電
幅と略一致させるとともに、前記少なくとも一方の電極
の長手方向に沿って該電極の左右両側に導電体を配設し
たことを特徴とするレーザ装置。(1) In a laser device that generates a laser beam by generating a discharge between two electrodes arranged vertically opposite to each other along the longitudinal direction of a laser chamber to excite a laser gas in the laser chamber, the above-mentioned 2 A laser device characterized in that the width of at least one of the two electrodes is made substantially equal to the discharge width, and conductors are disposed on both left and right sides of the at least one electrode along the longitudinal direction of the at least one electrode.
致し、かつ該電極の前記レーザチャンバの長手方向に垂
直な断面の鉛直中心軸が短径軸と一致するように前記断
面の外部ラインのうち前記他方の電極に対向する外郭ラ
インを楕円状に形成したものである請求項（１）記載の
レーザ装置。(2) The width of the at least one electrode matches the length of the major axis, and the external line of the cross section is aligned such that the vertical central axis of the cross section perpendicular to the longitudinal direction of the laser chamber of the electrode coincides with the minor axis. 2. The laser device according to claim 1, wherein the outer line facing the other electrode is formed in an elliptical shape.
４の範囲にしたものである請求項（２）記載のレーザ装
置。(3) The laser device according to claim 2, wherein the ratio of the length of the major axis to the length of the minor axis of the ellipse is in the range of 1 to 4.
たものである請求項（１）記載のレーザ装置。(4) The laser device according to claim (1), wherein the width of the electrode is equal to or less than the distance between the two electrodes.
る請求項（１）記載のレーザ装置。(5) The laser device according to claim (1), wherein the conductor is made of a material different from that of the electrode.
である請求項（１）記載のレーザ装置。(6) The laser device according to claim (1), wherein the conductor is housed in an insulating tube.
されたものである請求項（１）記載のレーザ装置。(7) The laser device according to claim (1), wherein a part of the surface of the conductor is coated with an insulating film.
直な断面の外部ラインは円形または円弧と直線とを組み
合わせたラインを有する形状である請求項（１）記載の
レーザ装置。(8) The laser device according to (1), wherein an external line of a cross section of the conductor perpendicular to the longitudinal direction of the laser chamber has a circular shape or a line that is a combination of an arc and a straight line.
が設けられ、該光共振器によって前記レーザ光の発振波
長を狭帯域化する狭帯域発振レーザ装置である請求項（
１）記載のレーザ装置。(9) The laser device is a narrowband oscillation laser device that is provided with an optical resonator having a wavelength selection element, and narrows the oscillation wavelength of the laser beam by the optical resonator.
1) The laser device described above.
して配設された２つの電極間で放電を行い、前記レーザ
チャンバ内のレーザガスを励起してレーザ光を発生させ
るレーザ装置において、 前記２つの電極のうち少なくとも一方の電極の長手方向
に沿った左右両側部分を中央部分の高さよりも小さくな
るように形成するとともに、前記中央部分をその横幅が
放電幅と略一致するように形成したことを特徴とするレ
ーザ装置。(10) In a laser device that generates a laser beam by generating a discharge between two electrodes disposed vertically and opposing each other along the longitudinal direction of a laser chamber to excite a laser gas in the laser chamber, the above-mentioned 2 The left and right side portions of at least one of the two electrodes along the longitudinal direction are formed so that the height thereof is smaller than the height of the central portion, and the central portion is formed such that the horizontal width thereof substantially matches the discharge width. A laser device featuring:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21960490A JP2926191B2 (en) | 1990-08-21 | 1990-08-21 | Laser device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21960490A JP2926191B2 (en) | 1990-08-21 | 1990-08-21 | Laser device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04101476A true JPH04101476A (en) | 1992-04-02 |
| JP2926191B2 JP2926191B2 (en) | 1999-07-28 |
Family
ID=16738136
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21960490A Expired - Lifetime JP2926191B2 (en) | 1990-08-21 | 1990-08-21 | Laser device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2926191B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06112554A (en) * | 1992-09-28 | 1994-04-22 | Komatsu Ltd | Laser device |
-
1990
- 1990-08-21 JP JP21960490A patent/JP2926191B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06112554A (en) * | 1992-09-28 | 1994-04-22 | Komatsu Ltd | Laser device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2926191B2 (en) | 1999-07-28 |
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