JPH04335352A - Mask for exposure - Google Patents
Mask for exposureInfo
- Publication number
- JPH04335352A JPH04335352A JP3135557A JP13555791A JPH04335352A JP H04335352 A JPH04335352 A JP H04335352A JP 3135557 A JP3135557 A JP 3135557A JP 13555791 A JP13555791 A JP 13555791A JP H04335352 A JPH04335352 A JP H04335352A
- Authority
- JP
- Japan
- Prior art keywords
- light
- glass substrate
- exposure
- mask
- scattered light
- 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.)
- Withdrawn
Links
- 239000011521 glass Substances 0.000 claims abstract description 49
- 239000000758 substrate Substances 0.000 claims abstract description 48
- 238000005286 illumination Methods 0.000 claims abstract description 14
- 239000000463 material Substances 0.000 claims abstract description 13
- 239000011651 chromium Substances 0.000 abstract description 7
- 101100269850 Caenorhabditis elegans mask-1 gene Proteins 0.000 abstract description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 abstract description 4
- 229910052804 chromium Inorganic materials 0.000 abstract description 4
- 238000007740 vapor deposition Methods 0.000 abstract description 3
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052750 molybdenum Inorganic materials 0.000 abstract description 2
- 239000011733 molybdenum Substances 0.000 abstract description 2
- 230000001678 irradiating effect Effects 0.000 abstract 2
- 230000002093 peripheral effect Effects 0.000 abstract 1
- 239000010408 film Substances 0.000 description 11
- 239000010409 thin film Substances 0.000 description 5
- 238000000034 method Methods 0.000 description 4
- 229920002120 photoresistant polymer Polymers 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 238000000059 patterning Methods 0.000 description 1
- 238000009751 slip forming Methods 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
Landscapes
- Preparing Plates And Mask In Photomechanical Process (AREA)
- Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
Abstract
Description
【0001】0001
【産業上の利用分野】本発明は、例えばICやLSI等
の製造工程においてパターン露光を行うための露光装置
で用いられる露光用マスクに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure mask used in an exposure apparatus for performing pattern exposure in the manufacturing process of, for example, ICs and LSIs.
【0002】0002
【従来の技術】ICやLSI等の製造工程においては、
一般的に、光を用いてウエハ(或いはウエハ上に形成さ
れている各種の薄膜)上のホトレジストにパターンを露
光する。このパターン露光には、密着露光、近接露光、
等倍投影露光、縮小投影露光等、様々な方法があるが、
何れも基本的には、所定のパターンを有する露光用マス
クを光源の光により照明し、その照明によって得られる
パターンの像をホトレジストに露光する。[Prior Art] In the manufacturing process of ICs, LSIs, etc.,
Generally, a pattern is exposed to photoresist on a wafer (or various thin films formed on the wafer) using light. This pattern exposure includes contact exposure, close exposure,
There are various methods such as 1:1 projection exposure, reduced projection exposure, etc.
In either case, basically, an exposure mask having a predetermined pattern is illuminated with light from a light source, and an image of the pattern obtained by the illumination is exposed onto a photoresist.
【0003】図3は縮小投影露光に用いられる従来の露
光用マスクの拡大断面図である。このマスク11は、石
英ガラス等からなるほぼ正方形状の透明なガラス基板1
2の表面(光の出射側)に、クロム(Cr)等の薄膜に
よって所定の回路パターン13が形成されたものである
。なお、縮小投影露光用のマスク11は拡大された回路
パターン13を有するものであり、通常、拡大マスク或
いはレチクルと称されている。FIG. 3 is an enlarged sectional view of a conventional exposure mask used for reduction projection exposure. This mask 11 consists of a substantially square transparent glass substrate 1 made of quartz glass or the like.
A predetermined circuit pattern 13 is formed on the surface (light emitting side) of 2 using a thin film of chromium (Cr) or the like. The mask 11 for reduction projection exposure has an enlarged circuit pattern 13, and is usually called an enlargement mask or reticle.
【0004】図4は上記マスク11が用いられる縮小投
影露光装置の概略斜視図である。この図において、例え
ば超高圧水銀灯からなる光源21の光によって、楕円集
光鏡22やコンデンサレンズ23等の照明光学系を介し
て、マスクマウント24に保持されたマスク11が一様
に照明される。図3に示すように、マスク11のガラス
基板12に入射される照明光Pは回路パターン13によ
り部分的に遮光され、露光光Qのみが出射される。そし
て、露光光Qによって得られる回路パターン13の像が
、図4に示すように、縮小レンズ25によってウエハ2
6上のホトレジストに縮小投影される。ウエハ26はX
Yステージ27上に支持されたウエハチャック28に保
持されており、XYステージ27によってウエハ26が
X、Y方向へ順次移動されながら縮小投影露光が繰り返
され、このステップアンドリピートによってウエハ26
の全面が露光される。FIG. 4 is a schematic perspective view of a reduction projection exposure apparatus in which the mask 11 described above is used. In this figure, a mask 11 held on a mask mount 24 is uniformly illuminated by light from a light source 21, such as an ultra-high pressure mercury lamp, through an illumination optical system such as an elliptical condenser mirror 22 and a condenser lens 23. . As shown in FIG. 3, the illumination light P incident on the glass substrate 12 of the mask 11 is partially blocked by the circuit pattern 13, and only the exposure light Q is emitted. Then, as shown in FIG.
6 is reduced and projected onto the photoresist above. Wafer 26 is X
The wafer 26 is held by a wafer chuck 28 supported on a Y stage 27, and reduction projection exposure is repeated while the wafer 26 is sequentially moved in the X and Y directions by the XY stage 27. Through this step and repeat, the wafer 26
The entire surface is exposed.
【0005】[0005]
【発明が解決しようとする課題】ところで、上述したよ
うな装置による露光の際、図3に示すように、前記光源
21からの光は適正な照明光Pとしてマスク11のガラ
ス基板12を照明するのであるが、往々にして、その光
源21からの光が照明光学系の各部で乱反射する等して
、散乱光Rが発生する場合がある。一方、マスク11の
ガラス基板12は透明なガラス材によって形成されてい
るので、露光の際に上述したような散乱光Rがあると、
その散乱光Rがガラス基板12の端面12aから内部に
入り込んでしまう。そして、この散乱光Rは、ガラス基
板12の内部で適正な照明光Pと干渉したり、ガラス基
板12を透過して適正な露光光Qと干渉する等して、パ
ターン像を崩す原因となる。このように、ガラス基板1
2の端面12aから内部に入り込む散乱光Rは、パター
ン露光に多大な悪影響を及ぼすという問題があった。な
お、露光装置自体において散乱光Rの発生防止対策を施
すことが考えられるが、これは装置の複雑化並びに高コ
スト化を招き、それでいて、散乱光Rの発生を完全に防
止するのは極めて困難である。By the way, during exposure using the above-mentioned apparatus, the light from the light source 21 illuminates the glass substrate 12 of the mask 11 as proper illumination light P, as shown in FIG. However, in some cases, the light from the light source 21 is diffusely reflected by various parts of the illumination optical system, resulting in scattered light R. On the other hand, since the glass substrate 12 of the mask 11 is made of a transparent glass material, if there is the above-mentioned scattered light R during exposure,
The scattered light R enters the inside of the glass substrate 12 from the end surface 12a. Then, this scattered light R interferes with the proper illumination light P inside the glass substrate 12 or interferes with the proper exposure light Q after passing through the glass substrate 12, causing the pattern image to collapse. . In this way, the glass substrate 1
There was a problem in that the scattered light R entering the inside from the end surface 12a of No. 2 had a great negative effect on pattern exposure. It is conceivable to take measures to prevent the occurrence of scattered light R in the exposure equipment itself, but this will make the equipment more complicated and expensive, and it is extremely difficult to completely prevent the occurrence of scattered light R. It is.
【0006】そこで本発明は、露光の際に無用な散乱光
がガラス基板の端面から内部に入り込むことを防止でき
るようにした露光用マスクを提供することを目的とする
。SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an exposure mask that can prevent unnecessary scattered light from entering the inside of a glass substrate from the end surface during exposure.
【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、本発明は、ガラス基板の表面に所定のパターンが形
成され、前記ガラス基板に入射させた照明光を前記パタ
ーンにより部分的に遮光して露光光を出射させる露光用
マスクにおいて、前記ガラス基板の端部に、外部からの
散乱光の入光を防止するための遮光部を有するものであ
る。なお、前記遮光部を前記ガラス基板の端面に形成さ
れた遮光膜によって構成することができ、この場合、遮
光膜の形成材料が前記パターンの形成材料と同一である
とよい。また、前記遮光部を前記ガラス基板の端部に設
けられた減光層によって構成することもできる。Means for Solving the Problems In order to achieve the above object, the present invention provides a method in which a predetermined pattern is formed on the surface of a glass substrate, and the illumination light incident on the glass substrate is partially blocked by the pattern. In the exposure mask that emits exposure light, the glass substrate has a light shielding part at an end thereof to prevent scattered light from entering from outside. Note that the light shielding portion can be formed by a light shielding film formed on an end surface of the glass substrate, and in this case, it is preferable that the material for forming the light shielding film is the same as the material for forming the pattern. Further, the light shielding section can also be constituted by a light attenuation layer provided at an end of the glass substrate.
【0008】[0008]
【作用】上記のように構成された本発明によれば、ガラ
ス基板の端部に遮光部が存在するので、露光の際に適正
な照明光以外の無用な散乱光が発生しても、その散乱光
がガラス基板の端面から内部に入り込むことを防止する
ことができる。[Operation] According to the present invention configured as described above, since there is a light shielding part at the edge of the glass substrate, even if unnecessary scattered light other than proper illumination light is generated during exposure, it will not be removed. Scattered light can be prevented from entering the inside from the end face of the glass substrate.
【0009】[0009]
【実施例】以下、本発明を縮小投影露光用マスク(いわ
ゆる拡大マスク或いはレチクル)に適用した実施例を図
1及び図2を参照して説明する。なお、この露光用マス
クが用いられる縮小投影露光装置は、図4に示した従来
の装置と実質的に同様でよい。DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a reduction projection exposure mask (so-called enlargement mask or reticle) will be described below with reference to FIGS. 1 and 2. Note that a reduction projection exposure apparatus using this exposure mask may be substantially the same as the conventional apparatus shown in FIG.
【0010】まず、図1は第1実施例における露光用マ
スクの拡大断面図である。このマスク1は、ほぼ正方形
状をなす透明なガラス基板2の表面(光の出射側)に所
定の回路パターン3が形成されたものである。ガラス基
板2は、熱膨張係数が小さくかつ紫外線透過率が大きい
ガラス材、例えば石英ガラスが用いられる。回路パター
ン3は、ガラス基板2の表面にクロム(Cr)等の薄膜
を例えば蒸着によって被着し、その薄膜にパターニング
したものである。First, FIG. 1 is an enlarged sectional view of an exposure mask in a first embodiment. This mask 1 has a predetermined circuit pattern 3 formed on the surface (light exit side) of a transparent glass substrate 2 having a substantially square shape. For the glass substrate 2, a glass material having a small thermal expansion coefficient and high ultraviolet transmittance, such as quartz glass, is used. The circuit pattern 3 is obtained by depositing a thin film of chromium (Cr) or the like on the surface of the glass substrate 2 by, for example, vapor deposition, and then patterning the thin film.
【0011】そして、このガラス基板2の外周における
全ての端面2aには遮光膜4が形成されている。この遮
光膜4は、クロム(Cr)、モリブデン(Mo)等の光
反射性の材料を用いるとよく、例えば蒸着によって形成
することができる。この場合、遮光膜4の形成材料を回
路パターン3の形成材料と同一にするのが好ましい。な
お、本実施例では、遮光膜4がガラス基板2の表面の外
周部にも回り込むように連続的に形成されている。[0011] A light shielding film 4 is formed on all end faces 2a on the outer periphery of the glass substrate 2. This light-shielding film 4 is preferably made of a light-reflective material such as chromium (Cr) or molybdenum (Mo), and can be formed, for example, by vapor deposition. In this case, it is preferable that the material for forming the light shielding film 4 is the same as the material for forming the circuit pattern 3. In this embodiment, the light shielding film 4 is continuously formed so as to extend around the outer circumference of the surface of the glass substrate 2 as well.
【0012】上述のように構成された露光用マスク1に
よれば、このマスク1を図4で説明した従来と同様な露
光装置に装着してパターン露光する際、図1に示すよう
に、ガラス基板2を適正に照明する照明光P以外に、ガ
ラス基板2の端面2aを照射するような散乱光Rが発生
しても、その散乱光Rは端面2aに形成された遮光膜4
によって反射されるので、散乱光Rが端面2aから内部
に入り込むことが防止される。なお、遮光膜4に回路パ
ターン3と同一の材料を用いると、ガラス基板2に回路
パターン3のための薄膜を被着させる際に、遮光膜4も
同時に被着させることができるので、特別な工程を必要
としない。また、近年、マスク1の外寸が大きくなる傾
向にあるので、本実施例のように遮光膜4をガラス基板
2の表面の外周部にも形成しておくと、その外周部にお
いても無用な散乱光の入光を防止することができる。According to the exposure mask 1 constructed as described above, when the mask 1 is attached to the conventional exposure apparatus described in FIG. 4 for pattern exposure, as shown in FIG. In addition to the illumination light P that properly illuminates the substrate 2, even if scattered light R that illuminates the end surface 2a of the glass substrate 2 is generated, the scattered light R will be transmitted to the light shielding film 4 formed on the end surface 2a.
Therefore, the scattered light R is prevented from entering the inside from the end surface 2a. Note that if the same material as the circuit pattern 3 is used for the light-shielding film 4, the light-shielding film 4 can also be deposited at the same time when the thin film for the circuit pattern 3 is deposited on the glass substrate 2. No process required. Furthermore, as the outer dimensions of the mask 1 tend to increase in recent years, if the light-shielding film 4 is also formed on the outer periphery of the surface of the glass substrate 2 as in this embodiment, there will be no need to use the outer periphery. It is possible to prevent scattered light from entering.
【0013】次に、図2は第2実施例における露光用マ
スク1の拡大断面図である。この例においては、ガラス
基板2の外周における全ての端面2aから内方へ一定の
厚さで減光層5が設けられている。この減光層5は、例
えばガラス基板2の端部に多数の気泡を形成したり、ガ
ラス基板2の端部の組成を変化させたりすることによっ
て設けることができる。Next, FIG. 2 is an enlarged sectional view of the exposure mask 1 in the second embodiment. In this example, the light attenuation layer 5 is provided with a constant thickness inward from all end faces 2a on the outer periphery of the glass substrate 2. This light attenuation layer 5 can be provided, for example, by forming a large number of bubbles at the edge of the glass substrate 2 or by changing the composition of the edge of the glass substrate 2.
【0014】この第2実施例によれば、露光の際に散乱
光Rがガラス基板2の端面2aに入り込むことがあって
も、その散乱光Rは減光層5内を進行するうちに次第に
減衰されていく。即ち、実質的に端面2aからの散乱光
Rの入光が防止されることになる。なお、多数の気泡や
組成変化等による減光層5は、ガラス基板2自体を加工
すると同時に、そのガラス基板2の熱処理や材料成分の
調整等よって設けることができるので、特別な工程を必
要としない。According to this second embodiment, even if the scattered light R may enter the end surface 2a of the glass substrate 2 during exposure, the scattered light R gradually disappears as it travels through the light attenuation layer 5. It is being attenuated. That is, the scattered light R is substantially prevented from entering from the end surface 2a. Note that the light-attenuating layer 5 due to a large number of bubbles, changes in composition, etc. can be provided by processing the glass substrate 2 itself and at the same time by heat-treating the glass substrate 2 or adjusting the material components, so no special process is required. do not.
【0015】以上、本発明の実施例に付き説明したが、
本発明は上記実施例に限定されることなく、本発明の技
術的思想に基づいて各種の有効な変更並びに応用が可能
である。例えば、遮光部は実施例以外にも各種の有効な
構成を採用することができ、その遮光部は円形のガラス
基板にも同様に設けることができる。なお本発明は、縮
小投影露光用マスク以外に、様々な露光用マスクに適用
することができる。The embodiments of the present invention have been described above, but
The present invention is not limited to the above-mentioned embodiments, and various effective changes and applications can be made based on the technical idea of the present invention. For example, the light shielding part can adopt various effective configurations other than those in the embodiment, and the light shielding part can be similarly provided on a circular glass substrate. Note that the present invention can be applied to various exposure masks other than reduction projection exposure masks.
【0016】[0016]
【発明の効果】以上説明したように、本発明によれば、
ガラス基板の端部に遮光部が存在するので、露光の際に
適正な照明光以外の無用な散乱光が発生しても、その散
乱光がガラス基板の端面から内部に入り込むことを防止
することができる。従って、散乱光がガラス基板の内部
で適正な照明光と干渉したり、ガラス基板を透過して適
正な露光光と干渉する等の問題がなく、極めて良好なパ
ターン露光を行うことができる。また、露光用マスク自
体で散乱光の入光を防止することによって、露光装置自
体に複雑でコスト高につく散乱光の発生防止対策を必ず
しも施す必要がないので、露光装置の簡素化並びに低コ
スト化を図ることができる。[Effects of the Invention] As explained above, according to the present invention,
Since there is a light shielding part at the edge of the glass substrate, even if unnecessary scattered light other than proper illumination light is generated during exposure, the scattered light is prevented from entering the inside from the end surface of the glass substrate. Can be done. Therefore, there is no problem that the scattered light interferes with proper illumination light inside the glass substrate or interferes with proper exposure light after passing through the glass substrate, and extremely good pattern exposure can be performed. In addition, by preventing the entrance of scattered light with the exposure mask itself, it is not necessary to take complicated and costly measures to prevent the occurrence of scattered light in the exposure equipment itself, which simplifies the exposure equipment and reduces costs. It is possible to aim for
【図1】本発明の第1実施例における縮小投影露光用マ
スクの拡大断面図である。FIG. 1 is an enlarged sectional view of a reduction projection exposure mask in a first embodiment of the present invention.
【図2】本発明の第2実施例における縮小投影露光用マ
スクの拡大断面図である。FIG. 2 is an enlarged sectional view of a reduction projection exposure mask in a second embodiment of the present invention.
【図3】従来の縮小投影露光用マスクの拡大断面図であ
る。FIG. 3 is an enlarged cross-sectional view of a conventional reduction projection exposure mask.
【図4】従来の露光用マスクが用いられる縮小投影露光
装置の概略斜視図である。FIG. 4 is a schematic perspective view of a reduction projection exposure apparatus using a conventional exposure mask.
1 露光用マスク 2 ガラス基板 2a 端面 3 回路パターン 4 遮光膜 5 減光層 P 照明光 Q 露光光 R 散乱光 1 Exposure mask 2 Glass substrate 2a End face 3 Circuit pattern 4. Light shielding film 5 Light attenuation layer P Illumination light Q Exposure light R Scattered light
Claims (4)
形成され、前記ガラス基板に入射させた照明光を前記パ
ターンにより部分的に遮光して露光光を出射させる露光
用マスクにおいて、前記ガラス基板の端部に、外部から
の散乱光の入光を防止するための遮光部を有することを
特徴とする露光用マスク。1. An exposure mask in which a predetermined pattern is formed on the surface of a glass substrate, and the illumination light incident on the glass substrate is partially blocked by the pattern and the exposure light is emitted. An exposure mask characterized by having a light-shielding portion at an end portion for preventing scattered light from entering from the outside.
形成された遮光膜によって構成した請求項1記載の露光
用マスク。2. The exposure mask according to claim 1, wherein the light shielding portion is constituted by a light shielding film formed on an end surface of the glass substrate.
の形成材料と同一である請求項2記載の露光用マスク。3. The exposure mask according to claim 2, wherein the material for forming the light shielding film is the same as the material for forming the pattern.
設けられた減光層によって構成した請求項1記載の露光
用マスク。4. The exposure mask according to claim 1, wherein the light shielding portion is constituted by a light attenuation layer provided at an end of the glass substrate.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3135557A JPH04335352A (en) | 1991-05-10 | 1991-05-10 | Mask for exposure |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3135557A JPH04335352A (en) | 1991-05-10 | 1991-05-10 | Mask for exposure |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH04335352A true JPH04335352A (en) | 1992-11-24 |
Family
ID=15154594
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3135557A Withdrawn JPH04335352A (en) | 1991-05-10 | 1991-05-10 | Mask for exposure |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH04335352A (en) |
-
1991
- 1991-05-10 JP JP3135557A patent/JPH04335352A/en not_active Withdrawn
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
A300 | Application deemed to be withdrawn because no request for examination was validly filed |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19980806 |