JPH05343284A - Projecting exposure apparatus and exposing method therefor - Google Patents
Projecting exposure apparatus and exposing method thereforInfo
- Publication number
- JPH05343284A JPH05343284A JP4146076A JP14607692A JPH05343284A JP H05343284 A JPH05343284 A JP H05343284A JP 4146076 A JP4146076 A JP 4146076A JP 14607692 A JP14607692 A JP 14607692A JP H05343284 A JPH05343284 A JP H05343284A
- Authority
- JP
- Japan
- Prior art keywords
- light source
- exposure apparatus
- projection exposure
- house
- air
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/708—Construction of apparatus, e.g. environment aspects, hygiene aspects or materials
- G03F7/70858—Environment aspects, e.g. pressure of beam-path gas, temperature
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/708—Construction of apparatus, e.g. environment aspects, hygiene aspects or materials
- G03F7/70858—Environment aspects, e.g. pressure of beam-path gas, temperature
- G03F7/70866—Environment aspects, e.g. pressure of beam-path gas, temperature of mask or workpiece
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/708—Construction of apparatus, e.g. environment aspects, hygiene aspects or materials
- G03F7/70858—Environment aspects, e.g. pressure of beam-path gas, temperature
- G03F7/70883—Environment aspects, e.g. pressure of beam-path gas, temperature of optical system
- G03F7/70891—Temperature
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Atmospheric Sciences (AREA)
- Toxicology (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Epidemiology (AREA)
- Public Health (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
- Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
- Projection-Type Copiers In General (AREA)
- Light Sources And Details Of Projection-Printing Devices (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、半導体装置などの製造
で行う投影露光に用いる投影露光装置及び露光方法に関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection exposure apparatus and an exposure method used for projection exposure performed in manufacturing semiconductor devices and the like.
【０００２】上記投影露光では、スループットが低下し
ないように投影露光装置の劣化を少なくすることが望ま
れる。In the above-mentioned projection exposure, it is desired to reduce deterioration of the projection exposure apparatus so as not to reduce the throughput.
【０００３】[0003]
【従来の技術】図３は従来例の投影露光装置の要部構成
図である。図３において、露光用の光源６からの光は、
楕円鏡７の反射によって集光され投影露光装置本体１２
内に送り込まれるが、光源６と楕円鏡７は投影露光装置
本体１２とは独立した光源ハウス５の中にある。光源ハ
ウス５は、光源６の発熱による楕円鏡７ならびにその他
の部品の温度上昇を抑えるよう換気によって空冷されて
いる。換気の方法はファン８による強制換気で、空気吸
入口から取り込まれたクリーンルーム内の空気が光源ハ
ウス５内を冷却し空気排出口から出て行くようになって
いる。2. Description of the Related Art FIG. 3 is a schematic view of a main part of a conventional projection exposure apparatus. In FIG. 3, the light from the light source 6 for exposure is
The projection exposure apparatus main body 12 is focused by the reflection of the elliptical mirror 7.
The light source 6 and the elliptic mirror 7 are fed into the light source house 5 independent of the projection exposure apparatus main body 12. The light source house 5 is air-cooled by ventilation so as to suppress the temperature rise of the elliptical mirror 7 and other parts due to the heat generation of the light source 6. The ventilation method is forced ventilation by the fan 8, and the air in the clean room taken in from the air intake port cools the inside of the light source house 5 and goes out from the air exhaust port.
【０００４】このことにより、クリーンルーム内の空気
が光源ハウス５内の楕円鏡７や他の光学部品に直接当た
るため、その空気に含まれている微量のガスが光源６か
らの強い紫外線によって化学反応を起こし、楕円鏡７や
他の光学部品に付着してそれらの表面が曇るという問題
があった。その化学反応例として、空気中のＮＨ
4 +（アンモニウムイオン）とＳＯ4 2- （硫酸イオン）
が（ＮＨ4)2 ＳＯ4 （硫酸アンモニウム）となって、楕
円鏡７の反射表面が白濁化する実例がある。この白濁に
よって露光エネルギーが半分以下に低下した。As a result, the air in the clean room directly hits the elliptic mirror 7 and other optical parts in the light source house 5, so that a small amount of gas contained in the air chemically reacts with strong ultraviolet rays from the light source 6. There is a problem in that the surface of the elliptic mirror 7 and other optical components adheres to the surface and becomes cloudy. As an example of the chemical reaction, NH in air
4 + (ammonium ion) and SO 4 2- (sulfate ion)
Becomes (NH 4 ) 2 SO 4 (ammonium sulfate), and the reflecting surface of the elliptical mirror 7 becomes white turbid. This cloudiness reduced the exposure energy to less than half.
【０００５】[0005]
【発明が解決しようとする課題】このように露光エネル
ギーが低下すると、露光時間を長くする必要があり結果
的に露光のスループットが落ちてしまう。この露光エネ
ルギーの低下を防止するためには、光源ハウス５内の楕
円鏡７や他の光学部品に曇りが生じないようにすれば良
い。When the exposure energy is lowered as described above, it is necessary to lengthen the exposure time, and as a result, the exposure throughput is lowered. In order to prevent the decrease of the exposure energy, it is sufficient to prevent the elliptic mirror 7 and other optical components in the light source house 5 from being fogged.
【０００６】そこで本発明は、半導体装置などの製造で
行う投影露光に関し、光源ハウス内の楕円鏡や他の光学
部品に曇りが生じ難い投影露光装置及び露光方法の提供
を目的とする。Therefore, the present invention relates to projection exposure performed in the manufacture of semiconductor devices and the like, and an object of the present invention is to provide a projection exposure apparatus and an exposure method in which the elliptic mirror and other optical parts in the light source house are less likely to be fogged.
【０００７】[0007]
【課題を解決するための手段】上記目的を達成するため
に、本発明による投影露光装置は、本発明の原理説明図
である図１を参照して、露光用の光源６と光源６からの
光を反射し集光させる楕円鏡７とを内部に有する光源ハ
ウス５が、換気されるようになっており（図ではファン
４による）、該換気の空気吸入口に空気清浄剤１を配置
してあることを特徴としている。また、この投影露光装
置において、楕円鏡７を加熱するヒータ２を有すること
を特徴としている。In order to achieve the above object, the projection exposure apparatus according to the present invention comprises a light source 6 for exposure and a light source 6 for exposure with reference to FIG. 1 which is an explanatory view of the principle of the present invention. A light source house 5 having an elliptical mirror 7 for reflecting and condensing light therein is designed to be ventilated (by a fan 4 in the figure), and an air cleaner 1 is arranged at an air intake port of the ventilation. It is characterized by the presence. Further, this projection exposure apparatus is characterized in that it has a heater 2 for heating the elliptic mirror 7.
【０００８】そして、露光方法は、クリーンルーム内で
上記投影露光装置を用いて投影露光を行うことを特徴と
している。The exposure method is characterized in that the projection exposure is performed in the clean room using the projection exposure apparatus.
【０００９】[0009]
【作用】上記換気のため光源ハウス５に取り込まれる空
気に楕円鏡７を曇らせる微量のガスが含まれていても、
そのガスは空気清浄剤１によって除去されるので、楕円
鏡７は曇りが生じ難くなる。光源ハウス５内の他の光学
部品も同様である。それでも楕円鏡７は、特に強い紫外
線が当たるので長期に渡れば空気清浄剤１をリークした
極々微量のガスによって曇る可能性がある。ヒータ２は
その曇りを生じさせる物質を昇華させて楕円鏡７を半永
久的に曇らないようにさせる。[Effect] Even if the air taken into the light source house 5 for the above-mentioned ventilation contains a small amount of gas that makes the elliptical mirror 7 cloudy,
Since the gas is removed by the air freshener 1, the elliptic mirror 7 is less likely to be fogged. The same applies to other optical components in the light source house 5. Nevertheless, the elliptic mirror 7 is exposed to particularly strong ultraviolet rays, so that it may be clouded by an extremely small amount of gas leaking the air cleaning agent 1 for a long period of time. The heater 2 sublimates the substance that causes the fogging so that the elliptical mirror 7 is semi-permanently prevented from fogging.
【００１０】そして、このようにした投影露光装置をク
リーンルーム内で用いれば、クリーンルーム内の空気に
含まれる微量のガスが一般ルーム内の空気に含まれる同
ガスより低濃度であることから、上記曇りがより一層生
じ難くなる。When such a projection exposure apparatus is used in a clean room, a trace amount of gas contained in the air in the clean room has a lower concentration than that of the gas contained in the air in the general room. Is more difficult to occur.
【００１１】[0011]
【実施例】以下本発明の実施例について図２を用いて説
明する。図２は実施例の投影露光装置の要部構成図であ
り、全図を通し同一符号は同一対象物を示す。EXAMPLE An example of the present invention will be described below with reference to FIG. FIG. 2 is a configuration diagram of essential parts of the projection exposure apparatus of the embodiment, and the same reference numerals denote the same objects throughout the drawings.
【００１２】図２において、この投影露光装置は、図３
で説明した従来例の光源ハウス５の空気吸入口に空気清
浄剤１とヘパフィルター３とファン４を配置して従来の
ファン８を外し、更に、楕円鏡７にヒータ２を配置した
ものである。In FIG. 2, this projection exposure apparatus is shown in FIG.
The air cleaner 1 and the hepafilter 3 and the fan 4 are arranged in the air inlet of the light source house 5 of the conventional example described in 1 above, the conventional fan 8 is removed, and the heater 2 is arranged on the elliptic mirror 7. .
【００１３】光源ハウス５を換気する空気は、空気清浄
剤１とヘパフィルター３とを順次に通り、ファン４によ
って光源ハウス５内に送り込まれている。ヘパフィルタ
ー３は、空気清浄剤１を通る前の空気に含まれる塵と共
に空気清浄剤１から出る塵を除去するために設けてあ
る。ファン４の配置は図ではヘパフィルター３の後にな
っているがそれより前であっても良い。ファン４を光源
ハウス５の空気吸入口に配置したのは、空気が投影露光
装置本体１２から光源ハウス５に入り込むのを避けるた
めであり、投影露光装置本体１２が密閉構造であるなら
ば従来のファン８をファン４の代わりにしても良い。The air for ventilating the light source house 5 sequentially passes through the air cleaner 1 and the hepa filter 3 and is sent into the light source house 5 by the fan 4. The hepa filter 3 is provided to remove the dust contained in the air before passing through the air freshener 1 and the dust emitted from the air freshener 1. The fan 4 is arranged after the hepa filter 3 in the drawing, but may be arranged before it. The reason why the fan 4 is arranged at the air inlet of the light source house 5 is to prevent air from entering the light source house 5 from the projection exposure apparatus main body 12. If the projection exposure apparatus main body 12 has a closed structure, The fan 8 may be used instead of the fan 4.
【００１４】空気清浄剤１は、その場の空気に含まれる
ガスに最も効果を示す種類のものを使用するのが良く、
実施例ではＮＨ4 + （アンモニウムイオン）とＳＯ4 2-
（硫酸イオン）に効果が大きい２種類の清浄剤を使用し
ている。その清浄剤は日本化学製のピュアライトであ
る。また、ヘパフィルター３は０．１μm のものを使用
している。As the air cleaner 1, it is preferable to use the kind which is most effective for the gas contained in the air in the place.
In the example, NH 4 + (ammonium ion) and SO 4 2-
Two kinds of detergents that have a great effect on (sulfate ion) are used. The detergent is Pure Light manufactured by Nippon Kagaku. Further, the hepa filter 3 having a thickness of 0.1 μm is used.
【００１５】ヒータ２は、シート状のものであって楕円
鏡７の非反射面に貼着してあり、楕円鏡７を設定温度に
保温できるしくみになっている。その温度は、ＮＨ4 +
とＳＯ4 2- が紫外線で反応して生成する（ＮＨ4)2 ＳＯ
4 （硫酸アンモニウム）の昇華温度（１２０℃）より高
く設定してある。The heater 2 is in the form of a sheet and is attached to the non-reflective surface of the elliptic mirror 7 so that the elliptic mirror 7 can be kept at a preset temperature. The temperature is NH 4 +
And SO 4 2- react with UV light to produce (NH 4 ) 2 SO
It is set higher than the sublimation temperature (120 ° C) of 4 (ammonium sulfate).
【００１６】ヒータ２の制御は、ヒーター２に電源供給
するヒーター電源９と、ヒーター電源９の出力を制御す
る温度コントローラー１０と、楕円鏡７の近傍に配置さ
れて楕円鏡７の温度を検出しその信号を温度コントロー
ラー１０に送る温度センサー１１とによって行われる。The heater 2 is controlled by a heater power supply 9 for supplying power to the heater 2, a temperature controller 10 for controlling the output of the heater power supply 9, and an elliptic mirror 7 arranged near the elliptic mirror 7 to detect the temperature of the elliptic mirror 7. The temperature sensor 11 sends the signal to the temperature controller 10.
【００１７】ちなみに、ヒーター２が無い場合の光源６
からの加熱による楕円鏡７の温度は、８０〜１００℃で
（ＮＨ4)2 ＳＯ4 の昇華温度より低い。楕円鏡７の温度
を１２０℃以上にする方策として光源６のパワーを大き
くすることが考えられるが、その場合は光源ハウス５内
の他の光学部品も温度が高くなるので問題である。Incidentally, the light source 6 without the heater 2
The temperature of the elliptical mirror 7 due to the heating from 80 to 100 ° C. is lower than the sublimation temperature of (NH 4 ) 2 SO 4 . As a measure for increasing the temperature of the elliptic mirror 7 to 120 ° C. or higher, it is conceivable to increase the power of the light source 6, but in that case, the temperature of other optical components in the light source house 5 also becomes high, which is a problem.
【００１８】上述した実施例の投影露光装置は、先に述
べた露光エネルギーが例えば１０％低下するまでの使用
時間が従来例の投影露光装置の２０倍をはるかに越えて
どこまで延びるか不明であり、ヒーター２による楕円鏡
７の加熱を行わなくとも１０倍を越えていた。また、従
来例の投影露光装置をクリーンルームで使用した場合と
一般ルームで使用した場合との間で上記使用時間に差が
あり、前者の方が後者の３倍程度であったので、実施例
の投影露光装置においても、クリーンルームで使用する
ことが上記使用時間の延伸に有効であると判断される。In the projection exposure apparatus of the above-mentioned embodiment, it is unknown how long the operating time until the above-mentioned exposure energy decreases by, for example, 10% far exceeds 20 times that of the conventional projection exposure apparatus. Even if the elliptic mirror 7 was not heated by the heater 2, it exceeded 10 times. Further, there is a difference in the above-mentioned usage time between the case where the projection exposure apparatus of the conventional example is used in a clean room and the case where it is used in a general room, and the former is about 3 times as long as the latter, so that Even in the projection exposure apparatus, it is judged that use in a clean room is effective in extending the above-mentioned use time.
【００１９】[0019]
【発明の効果】以上説明したように本発明によれば、半
導体装置などの製造で行う投影露光に関し、光源ハウス
内の楕円鏡や他の光学部品に曇りが生じ難い投影露光装
置及び露光方法が提供されて、長期に渡り一定の露光エ
ネルギーが得られるようになり、スループットの低下抑
制を可能にさせる効果がある。As described above, according to the present invention, there is provided a projection exposure apparatus and an exposure method which are less likely to cause fog on an elliptical mirror or other optical parts in a light source house in projection exposure performed in manufacturing a semiconductor device or the like. By being provided, a constant exposure energy can be obtained for a long period of time, and there is an effect that it is possible to suppress a decrease in throughput.
【図１】 本発明の原理説明図FIG. 1 is an explanatory view of the principle of the present invention.
【図２】 実施例の投影露光装置の要部構成図FIG. 2 is a configuration diagram of a main part of a projection exposure apparatus according to an embodiment.
【図３】 従来例の投影露光装置の要部構成図FIG. 3 is a configuration diagram of main parts of a conventional projection exposure apparatus.
１ 空気清浄剤 ２ ヒーター ３ ヘパフィルター ４ ファン ５ 光源ハウス ６ 光源 ７ 楕円鏡 ８ ファン ９ ヒーター電源 １０ 温度コントローラ １１ 温度センサー １２ 投影露光装置本体 1 Air Cleaning Agent 2 Heater 3 Hepa Filter 4 Fan 5 Light Source House 6 Light Source 7 Elliptical Mirror 8 Fan 9 Heater Power Supply 10 Temperature Controller 11 Temperature Sensor 12 Projection Exposure System Main Unit
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.5 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｇ０３Ｆ 7/20 ５２１ 9122−2Ｈ ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 5 Identification code Internal reference number FI technical display location G03F 7/20 521 9122-2H
Claims (3)
光源（６）と該光源（６）からの光を反射し集光させる
楕円鏡（７）とを内部に有する光源ハウス（５）が、換
気されるようになっており、該換気の空気吸入口に空気
清浄剤（１）を配置してあることを特徴とする投影露光
装置。1. A light source house (5) for performing projection exposure, comprising a light source (6) for exposure and an elliptical mirror (7) for reflecting and condensing light from the light source (6). ) Is ventilated, and an air cleaner (1) is arranged at an air intake of the ventilation.
前記楕円鏡（７）を加熱するヒータ（２）を有すること
を特徴とする投影露光装置。2. The projection exposure apparatus according to claim 1, wherein
A projection exposure apparatus comprising a heater (2) for heating the elliptical mirror (7).
載の投影露光装置を用いて投影露光を行うことを特徴と
する露光方法。3. An exposure method, wherein projection exposure is performed in a clean room using the projection exposure apparatus according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4146076A JPH05343284A (en) | 1992-06-08 | 1992-06-08 | Projecting exposure apparatus and exposing method therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4146076A JPH05343284A (en) | 1992-06-08 | 1992-06-08 | Projecting exposure apparatus and exposing method therefor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05343284A true JPH05343284A (en) | 1993-12-24 |
Family
ID=15399567
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4146076A Pending JPH05343284A (en) | 1992-06-08 | 1992-06-08 | Projecting exposure apparatus and exposing method therefor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05343284A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006222130A (en) * | 2005-02-08 | 2006-08-24 | Nsk Ltd | Exposure apparatus |
| JP2011114001A (en) * | 2009-11-24 | 2011-06-09 | Canon Inc | Exposure apparatus and device manufacturing method using the same |
-
1992
- 1992-06-08 JP JP4146076A patent/JPH05343284A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006222130A (en) * | 2005-02-08 | 2006-08-24 | Nsk Ltd | Exposure apparatus |
| JP2011114001A (en) * | 2009-11-24 | 2011-06-09 | Canon Inc | Exposure apparatus and device manufacturing method using the same |
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