JP6213960B2

JP6213960B2 - Substrate holder

Info

Publication number: JP6213960B2
Application number: JP2013233649A
Authority: JP
Inventors: 康世松浦; 征秀加藤; 康浩梅津; 磯貝　宏道; 宏道磯貝
Original assignee: Techno Quartz Inc
Current assignee: Techno Quartz Inc
Priority date: 2013-11-12
Filing date: 2013-11-12
Publication date: 2017-10-18
Anticipated expiration: 2033-11-12
Also published as: JP2015094002A

Description

本発明は、例えば液晶パネルまたはウェーハの露光装置用ないし検査装置用の基板を保持する基板保持盤に好適で、基板保持盤の全周面にＤＬＣ（ダイヤモンドライクカーボン）膜を被覆し、基板載置面の摩耗を防止し基板の摺動を円滑にするとともに、側面のＤＬＣ膜の膜厚を他部位周面よりも厚く形成して、露光または検査時に側面から基板保持盤へ入射する光を抑制し基板載置面の低反射率を維持して、露光装置ないし検査装置の大型化と表面の低反射率化を図るとともに、他部位周面のＤＬＣ膜の膜厚を薄膜化して、ＤＬＣ膜コーティングの合理化と低廉化を図り安価に製作できるようにした、基板保持盤に関する。 The present invention is suitable for, for example, a substrate holding plate for holding a substrate for a liquid crystal panel or wafer exposure apparatus or inspection apparatus. A DLC (diamond-like carbon) film is coated on the entire peripheral surface of the substrate holding plate to mount the substrate. The surface of the DLC film on the side surface is made thicker than the peripheral surface of other parts to prevent wear on the mounting surface, and light incident on the substrate holding plate from the side surface during exposure or inspection Suppressing and maintaining the low reflectivity of the substrate mounting surface to increase the size of the exposure apparatus or inspection apparatus and reduce the reflectivity of the surface, and reduce the thickness of the DLC film on the peripheral surface of the other part to reduce the DLC. achieving rationalization and cost reduction of the membrane coating was to be manufactured at a low cost, it relates to a substrate holding plate.

微細なパタ−ンを形成する露光装置では、波長３６５ｎｍ（ｉ線）、４０５ｎｍ（ｈ線）、４３６ｎｍ（ｇ線）の光線が使用され、光学検査用の装置では、白色光が使用される
これらの装置において、液晶パネル基板やＳｉＣウェ−ハ等の透明基板を対象として露光処理または光学的な検査をする場合、基板保持盤からの光の反射によって、露光が不要な領域まで光が照射されたり、反射光のコントラストの変化から傷や異物等の擬似的な欠陥が検出されたりする不具合が生じていた。 In an exposure apparatus that forms a fine pattern, light beams having wavelengths of 365 nm (i-line), 405 nm (h-line), and 436 nm (g-line) are used, and in an optical inspection apparatus, white light is used. In the above-mentioned apparatus, when an exposure process or optical inspection is performed on a transparent substrate such as a liquid crystal panel substrate or a SiC wafer, light is irradiated to an area that does not require exposure due to reflection of light from the substrate holder. Or a flaw such as a flaw or a foreign object is detected from a change in contrast of reflected light.

このため、基板保持盤表面を黒色化したり粗面にして、前記表面の低反射率化を図るようにしている。
例えば、黒色系セラミックス製の基板保持盤表面を所定の粗面に研削後、ブラスト加工したり、アルミニウム製の基板載置台の表面をアルマイト処理して艶消し処理し、基板保持盤表面を低反射率化したものがある（例えば、特許文献１および２参照）。 For this reason, the surface of the substrate holding plate is blackened or roughened to reduce the reflectance of the surface.
For example, the surface of the substrate holding board made of black ceramics is ground to a specified rough surface and then blasted, or the surface of the aluminum substrate mounting table is alumite treated to make the surface of the board holding plate low reflective. There are some which have become efficient (see, for example, Patent Documents 1 and 2).

しかし、前者の場合は、セラミックス製基板保持盤の焼結成形時に収縮や割れを生じ易いため、大型化が難しく歩留まりが低い上に、反射率が６〜１０%と比較的高いという問題があった。また、後者の場合は、母材であるアルミニウムの熱変形による露光精度の低下や、繰り返し使用による載置面の摩耗によって、反射率が経年的に上昇変化する問題があった。 However, in the former case, shrinkage and cracking are liable to occur during the sintering of the ceramic substrate holder, so that it is difficult to increase the size and the yield is low, and the reflectivity is relatively high at 6 to 10%. It was. In the latter case, there is a problem that the reflectance increases and changes over time due to a decrease in exposure accuracy due to thermal deformation of aluminum as a base material and wear of the mounting surface due to repeated use.

このような問題を解決するものとして、基板保持盤の表面に第１の被覆層を被覆し、この第１の被覆層を透明材料からなる第２の被覆層で被覆したものや、冶具本体表面にＳｉＣ製の内部層とＡｌ₂Ｏ₃製の透明な表面層との二層からなるセラミック薄膜層を被覆したもの、更にアルミニウム板等の母材表面にセラミックス皮膜を溶射し、該セラミックス皮膜の表面に凹凸部を形成し、該凹凸部の表面に透明な超薄膜を形成して、基板保持盤の表面の反射率を低くしたものがある（例えば、特許文献３乃至５参照）。 In order to solve such problems, the surface of the substrate holding plate is coated with a first coating layer, and the first coating layer is coated with a second coating layer made of a transparent material, or the surface of the jig body. A ceramic thin film layer comprising two layers of an inner layer made of SiC and a transparent surface layer made of Al ₂ O ₃ was coated, and a ceramic film was sprayed on the surface of a base material such as an aluminum plate. There is a type in which a concavo-convex portion is formed on the surface and a transparent ultra-thin film is formed on the surface of the concavo-convex portion to reduce the reflectance of the surface of the substrate holder (see, for example, Patent Documents 3 to 5).

しかし、前記内外二層の被覆層ないし皮膜は製作に手間が掛かり高価になるとともに、前二者の保持盤表面の反射率は約１３％で高く、また後者の反射率は６〜７％であるが、均一なセラミックス皮膜を得難く、またその製作が高価になって近時の低反射率化と大型化ないしその軽量化と高精度化への対応が難しいという問題があった。 However, the inner and outer two coating layers or coatings are time-consuming and expensive to manufacture, and the former two holders have a high reflectance of about 13%, and the latter has a reflectance of 6-7%. However, there is a problem that it is difficult to obtain a uniform ceramic film, and the production thereof is expensive, and it is difficult to cope with the recent low reflectance, large size, light weight, and high accuracy.

ところで、基板保持盤は経年的な使用によって基板の載置面が摩耗するため、基板保持盤の表面と裏面並びに側面に、耐摩耗性と摺動性に優れるＤＬＣ膜をコーティングして、摩耗を抑制するとともに、基板の摺動を円滑にするようにしたものがある（例えば、特許文献６および７参照）。 By the way, since the mounting surface of the substrate wears over time due to the use of the substrate holding plate, the surface, the back surface and the side surface of the substrate holding plate are coated with a DLC film having excellent wear resistance and slidability. There is one that suppresses and makes the substrate slide smoothly (see, for example, Patent Documents 6 and 7).

しかし、これらの基板保持盤は、低反射率を得るための適切なＤＬＣ膜の厚さが明示されておらず、一様な厚さのＤＬＣ膜コーティングで低反射率を得ようとすると、膜厚が１０μｍ以上も必要となり、コーティングに時間が掛かりコ−ティング費用が高価になるとともに、ＤＬＣ膜の残留応力の増加によって剥離し易くなる問題があった。
また、ＤＬＣ膜が経年的な使用によって摩耗すると、基板載置面が短期間で摩耗し、基板の露光時に外部に散乱した光や周辺の光が側面のＤＬＣ膜から基板保持盤に入射して反射率が変化し、良好で一様な露光作用を得られず、近時の基板保持盤の大型化と低反射率化に対応できなくなる等の問題があった。 However, these substrate holders do not clearly show the appropriate DLC film thickness for obtaining a low reflectivity, and when attempting to obtain a low reflectivity with a uniform DLC film coating, The thickness is required to be 10 μm or more, and it takes time to coat and the coating cost is high, and there is a problem that it is easy to peel off due to an increase in residual stress of the DLC film.
In addition, when the DLC film is worn out over time, the substrate mounting surface is worn out in a short period of time, and light scattered around the substrate and surrounding light are incident on the substrate holding plate from the side DLC film. There was a problem that the reflectivity changed, a good and uniform exposure action could not be obtained, and it was not possible to cope with the recent increase in size and low reflectivity of the substrate holding plate.

特許文献１：特許第４５１８８７６号公報
特許文献２：特開２００５−３３２９１０号公報
特許文献３：特許第３０９５５１４号公報
特許文献４：特開平８−１３９１６８号公報
特許文献５：特開２０１２−２０３２８６号公報
特許文献６：特開２００５−１０１２４７号公報
特許文献７：特開２００４−９１６５号公報 Patent Document 1: Japanese Patent No. 4518887 Patent Document 2: Japanese Patent Laid-Open No. 2005-332910 Patent Document 3: Japanese Patent No. 3095514 Patent Document 4: Japanese Patent Laid-Open No. 8-139168 Patent Document 5: Japanese Patent Laid-Open No. 2012-203286 Patent Document 6: Japanese Patent Application Laid-Open No. 2005-101247 Patent Document 7: Japanese Patent Application Laid-Open No. 2004-9165

本発明はこのような問題を解決し、例えば液晶パネルまたはウェーハの露光装置用ないし検査装置用の基板を保持する基板保持盤に好適で、基板保持盤の全周面にＤＬＣ（ダイヤモンドライクカーボン）膜を被覆し、基板載置面の摩耗を防止し基板の摺動を円滑にするとともに、側面のＤＬＣ膜の膜厚を他部位周面よりも厚く形成して、露光または検査時に側面から基板保持盤へ入射する光を抑制し基板載置面の低反射率を維持し、露光装置ないし検査装置の大型化と表面の低反射率化を図るとともに、他部位周面のＤＬＣ膜の膜厚を薄膜化して、ＤＬＣ膜コーティングの合理化と低廉化を図り安価に製作できるようにした、基板保持盤を提供することを目的とする。 The present invention solves such a problem, and is suitable for a substrate holding plate for holding a substrate for a liquid crystal panel or wafer exposure device or inspection device, for example, and DLC (Diamond Like Carbon) on the entire peripheral surface of the substrate holding plate. Covers the film, prevents abrasion of the substrate mounting surface, makes the substrate slide smoothly, and forms the DLC film on the side surface thicker than the peripheral surface of the other part, so that the substrate is exposed from the side surface during exposure or inspection. The light incident on the holding plate is suppressed to maintain the low reflectivity of the substrate mounting surface, and the exposure apparatus or inspection apparatus is increased in size and the surface has a low reflectivity. An object of the present invention is to provide a substrate holding plate that can be manufactured at a low cost by reducing the thickness of the DLC film and thereby rationalizing and reducing the cost of the DLC film coating.

請求項１の発明は、母材表面側に複数のピンと凹部と吸引孔を形成し、母材表面と裏面および側面の全周面と前記吸引孔の内面をＤＬＣ（ダイヤモンドライクカーボン）コーティングし、前記側面のＤＬＣ膜の膜厚を、前記側面以外の他部位周面のＤＬＣ膜よりも肉厚に形成した基板保持盤において、少なくとも前記ピンと凹部を含む母材表面側のＤＬＣ膜に透明な薄膜をコーティングし、母材表面の透明な薄膜によって低反射率化を促進し、良好な露光作用ないし検査精度または検査環境を得られるとともに、母材表面側のＤＬＣ膜の損傷によって母材が露出しても低反射率を維持して、良好な露光作用ないし検査精度または検査環境を得られ、露光装置ないし検査装置の大型化と高精度化と高機能化を図る一方、他部位周面のＤＬＣ膜の薄膜化を図り、そのＤＬＣ膜コーティング時間と費用を低減して、合理的かつ安価に製作し得るようにするとともに、一部のＤＬＣ膜が剥離しても、しばらくの間、継続使用ないし装置の稼働率と生産性の向上を図るようにし、しかも吸引孔の内面をＤＬＣコーティングし、吸引孔による反射を防止して、基板保持盤表面の低反射率化を促進するようにしている。 In the first aspect of the present invention, a plurality of pins, recesses and suction holes are formed on the surface side of the base material, and the entire surface of the base material surface, the back surface and the side surface and the inner surface of the suction hole are DLC (diamond-like carbon) coated , A thin film transparent to the DLC film on the surface side of the base material including at least the pins and the recesses in the substrate holding plate in which the thickness of the DLC film on the side surface is made thicker than the DLC film on the peripheral surface of the other part other than the side surface The substrate is coated with a transparent thin film on the surface of the base material to promote low reflectivity, so that a good exposure action, inspection accuracy or inspection environment can be obtained, and the base material is exposed due to the damage of the DLC film on the surface of the base material. However, while maintaining a low reflectivity, it is possible to obtain a good exposure action or inspection accuracy or inspection environment, and to increase the size, accuracy, and functionality of the exposure apparatus or inspection apparatus, while DLC on the peripheral surface of other parts Membrane Achieving form a film, by reducing the DLC film coating time and expense, as well as to be produced reasonably low cost, also a part of the DLC film is peeled off, while, to not continue using apparatus I Ru FIG increased productivity and utilization Unishi, yet to DLC coating an inner surface of the suction holes, to prevent reflection by the suction holes, and by Unishi to promote reduction of reflectance of the substrate holding plate surface .

請求項２の発明は、薄膜の膜厚を２μｍ以下に形成し、基板保持盤の平面度を維持して低反射率化を保持するようにしている。 The invention of claim 2, the thickness of the thin film is formed 2μm or less, and the so that to hold the reduction of reflectance to maintain the flatness of the substrate holding plate.

請求項３の発明は、母材表面の全反射率を５％以下にし、従来の基板保持盤に比べて全反射率を低下し、露光装置における二重露光を確実に防止して良好な露光作用ないし検査精度または検査環境を得られるようにしている。また、検査装置においては、反射光強度が低くなることによって、保持盤に起因するコントラスト変化を抑制し、検査基板の欠陥に起因するコントラストの変化を確実に検出できるようにしている。 The invention of claim 3 makes the total reflectance of the base material surface 5% or less, lowers the total reflectance as compared with the conventional substrate holder, and reliably prevents double exposure in the exposure apparatus. Action, inspection accuracy or inspection environment can be obtained. Further, in the inspection device, by the reflected light intensity is lowered, suppressing the contrast change due to the retaining disc, and in so that can reliably detect a change in contrast due to the defect of the test board.

請求項１の発明は、少なくとも前記ピンと凹部を含む母材表面側のＤＬＣ膜に透明な薄膜をコーティングしたから、母材表面の透明な薄膜によって低反射率化を促進し、良好な露光作用ないし検査精度または検査環境を得られるとともに、母材表面側のＤＬＣ膜の損傷によって母材が露出しても低反射率を維持して、良好な露光作用ないし検査精度または検査環境を得られ、露光装置ないし検査装置の大型化と高精度化と高機能化を図る一方、他部位周面のＤＬＣ膜の薄膜化を図り、そのＤＬＣ膜コーティング時間と費用を低減して、合理的かつ安価に製作し得るようにするとともに、一部のＤＬＣ膜が剥離しても、しばらくの間、継続使用ないし装置の稼働率と生産性の向上を図るようにし、しかも吸引孔の内面をＤＬＣコーティングし、吸引孔による反射を防止して、基板保持盤表面の低反射率化を促進することができる。 In the first aspect of the present invention , since a transparent thin film is coated on the DLC film on the base material surface side including at least the pins and the recesses, the transparent thin film on the base material surface promotes a low reflectivity, and good exposure action or In addition to obtaining inspection accuracy or inspection environment and maintaining low reflectivity even when the base material is exposed due to damage to the DLC film on the surface of the base material, it is possible to obtain good exposure action or inspection accuracy or inspection environment, and exposure While increasing the size, accuracy, and functionality of equipment and inspection equipment, the DLC film on the periphery of other parts is made thinner, and the DLC film coating time and cost are reduced, making it reasonably and inexpensively. together so as to be, even if some of the DLC film is peeled off, while, by Ru FIG increased productivity and utilization of from continued use device Unishi, yet to DLC coating an inner surface of the suction holes , To prevent reflection by引孔can facilitate the reduction of reflectance of the substrate holding plate surface.

請求項２の発明は、薄膜の膜厚を２μｍ以下に形成したから、基板保持盤の平面度を維持し低反射率化を保持することができる。 In the second aspect of the present invention, since the thickness of the thin film is 2 μm or less, the flatness of the substrate holder can be maintained and the low reflectance can be maintained .

請求項３の発明は、母材表面の全反射率を５％以下にしたから、従来の基板保持盤に比べて全反射率を低下し、露光装置における二重露光を確実に防止して良好な露光作用ないし検査精度または検査環境を得られるようにしている。また、検査装置においては、反射光強度が低くなることによって、保持盤に起因するコントラスト変化を抑制し、検査基板の欠陥に起因するコントラストの変化を確実に検出することがきる。 In the invention of claim 3 , since the total reflectivity of the base material surface is 5% or less, the total reflectivity is reduced as compared with the conventional substrate holding plate, and double exposure in the exposure apparatus is reliably prevented, which is good. It is possible to obtain a sufficient exposure action, inspection accuracy or inspection environment. Further, in the inspection apparatus, the reflected light intensity is lowered, so that the contrast change due to the holding plate can be suppressed, and the contrast change due to the defect of the inspection substrate can be detected reliably .

本発明を適用した基板と基板保持盤の要部を拡大して示す斜視図である。It is a perspective view which expands and shows the principal part of the board | substrate and board | substrate holding board to which this invention is applied. 図１のＡ−Ａ線に沿う基板保持盤の拡大断面図である。It is an expanded sectional view of the board | substrate holding board along the AA line of FIG. 本発明に係る基板保持盤の製造工程を順に示す説明図で、（ａ）は基板保持盤の母材を板状に切断した拡大断面図、（ｂ）は切断した板状の母材に吸引孔を加工した状況を示す拡大断面図、（ｃ）は吸引孔を形成後の表面にエッジとピンと凹部を形成した状況の要部を示す拡大断面図、（ｄ）は前記加工後の表面側にＤＬＣ膜をコーティングした前半の状況の要部を示す拡大断面図、（ｅ）は前半コーティング後、基板を反転し裏面側にＤＬＣ膜をコーティングした後半の状況の要部を示す拡大断面図、（ｆ）はＤＬＣ膜コーティング後の表面に薄膜をコーティングした状況の要部を示す拡大断面図である。BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the manufacturing process of the board | substrate holding board which concerns on this invention in order, (a) is an expanded sectional view which cut | disconnected the base material of the board | substrate holding board in plate shape, (b) is attracted | sucked to the cut plate-shaped base material. An enlarged cross-sectional view showing the state of processing the hole, (c) is an enlarged cross-sectional view showing the main part of the state where the edge, the pin and the recess are formed on the surface after forming the suction hole, (d) is the surface side after the processing An enlarged cross-sectional view showing the main part of the first half of the situation where the DLC film is coated on, (e) is an enlarged cross-sectional view showing the main part of the second half of the situation where the substrate is inverted and the back side is coated with the DLC film after the first half coating, (F) is an expanded sectional view which shows the principal part of the condition which coated the thin film on the surface after DLC film coating.

本発明の基板保持盤の種々の実験例の要部を示す拡大断面図で、（ａ）〜（ｅ）は実験例１〜５を示している。It is an expanded sectional view which shows the principal part of the various experiment examples of the board | substrate holding board of this invention, (a)-(e) has shown Experiment Examples 1-5. 前記実験例２，３と従来技術の全反射率の測定結果を比較して示すグラフである。It is a graph which compares and shows the measurement result of the total reflectance of the said experimental examples 2 and 3 and a prior art.

以下、本発明を液晶露光装置の液晶基板保持盤に適用した図示の実施形態について説明すると、図１乃至図４において１は石英ガラスを母材とする透明な基板保持盤で、矩形板状に形成され、その表面１ａの周囲にエッジ２が突設され、該エッジ２の内側の表面１ａ側に多数のピン３と凹部４がそれぞれ等間隔に形成され、このピン３上にウエハ等の石英ガラス製の基板５を載置している。 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention applied to a liquid crystal substrate holding disk of a liquid crystal exposure apparatus will be described below. In FIGS. An edge 2 is formed around the surface 1a, and a large number of pins 3 and recesses 4 are formed at equal intervals on the surface 1a on the inner side of the edge 2. On the pins 3, quartz such as a wafer is formed. A glass substrate 5 is placed.

前記ピン３と凹部４は、表面１ａの表面を所望の平面度に研削後、サンドブラストまたは研削加工によって形成され、このうちピン３はエッジ２よりも幅狭の直径１ｍｍφ、高さ０．２ｍｍの円錐台形状または円筒状に形成され、隣接するピン３とは２ｍｍピッチで形成されている。
前記適宜な凹部４に吸引孔６が形成され、該吸引孔６の下側開口部は真空ポンプ（図示略）に連通していて、ピン３周辺の空気を吸引して減圧し、ピン３上に載置した基板５を吸着保持するようにしている。 The pin 3 and the recess 4 are formed by sand blasting or grinding after the surface 1a is ground to a desired flatness. Of these, the pin 3 has a diameter 1 mmφ narrower than the edge 2 and a height of 0.2 mm. It is formed in a truncated cone shape or a cylindrical shape, and is formed at a pitch of 2 mm with the adjacent pins 3.
A suction hole 6 is formed in the appropriate recess 4, and the lower opening of the suction hole 6 communicates with a vacuum pump (not shown). The substrate 5 placed on the substrate is sucked and held.

前記基板保持盤１の全周面、すなわち表面１ａ側のエッジ２とピン３と凹部４の全周面、および裏面１ｂの全周面と側面１ｃの全周面、吸引孔６の内面全面に耐磨耗性と摺動性に優れ、導電性を有するＤＬＣ膜７，７ａがコーティングされている。
このうち、側面１ｃの全周面を除くＤＬＣ膜７の膜厚を１０μｍ以下、実施形態では３μｍ以下に形成し、側面１ｃの全周面のＤＬＣ膜７ａの膜厚を３〜６μｍに形成し、側面１ｃのＤＬＣ膜７ａを他のＤＬＣ膜７よりも肉厚に形成している。 On the entire peripheral surface of the substrate holder 1, that is, the entire peripheral surface of the edge 2, the pin 3 and the recess 4 on the front surface 1 a side, the entire peripheral surface of the back surface 1 b and the side surface 1 c, and the entire inner surface of the suction hole 6. The DLC films 7 and 7a, which are excellent in wear resistance and slidability and have conductivity, are coated.
Of these, the thickness of the DLC film 7 excluding the entire peripheral surface of the side surface 1c is formed to be 10 μm or less, in the embodiment, 3 μm or less, and the thickness of the DLC film 7a on the entire peripheral surface of the side surface 1c is formed to 3 to 6 μm. The DLC film 7a on the side surface 1c is formed thicker than the other DLC films 7.

前記ＤＬＣ膜７，７ａは、基板保持盤１に対するピン３と凹部４と吸引孔６の形成後、例えば実施形態のようなプラズマＣＶＤ法、或いはスパッタリング法によってコーティングしている。
すなわち、前記各部を形成した基板保持盤１を反応器８に搬入し、これを反応器８内に配置したカソード電極９に載置し、このカソード電極９と対向配置したアノード電極（図示略）間に高周波電圧を印加する。 The DLC films 7 and 7a are coated by, for example, the plasma CVD method or the sputtering method as in the embodiment after the pins 3, the recesses 4 and the suction holes 6 are formed on the substrate holding plate 1.
That is, the substrate holding plate 1 in which each part is formed is carried into the reactor 8, placed on the cathode electrode 9 disposed in the reactor 8, and an anode electrode (not shown) disposed opposite to the cathode electrode 9. A high frequency voltage is applied between them.

これと同時に反応器８の入口側（図示略）から、例えば原料ガスであるメタンを供給して原料ガスをプラズマ１０化し、反応器８内部のガスを出口側（図示略）から真空ポンプ（図示略）で排出する。
このようにして、原料ガスのメタンを分解し、分解した炭素をカソ−ド電極９上の基板保持盤１に付着させＤＬＣ膜７を堆積して、凹部４と吸引孔６の内面を含む基板保持盤１の表面１ａ側周面と、側面１ｃ周面にＤＬＣ膜をコ−ティングする。 At the same time, for example, methane, which is a raw material gas, is supplied from the inlet side (not shown) of the reactor 8 to turn the raw material gas into a plasma 10, and the gas inside the reactor 8 is vacuum pumped (not shown) from the outlet side (not shown). Omitted).
In this way, the source gas methane is decomposed, the decomposed carbon is attached to the substrate holding plate 1 on the cathode electrode 9, the DLC film 7 is deposited, and the substrate including the recess 4 and the inner surface of the suction hole 6 is deposited. A DLC film is coated on the peripheral surface of the holding surface 1 on the surface 1a side and the peripheral surface of the side surface 1c.

そして、前記周面を所定肉厚にＤＬＣ膜コーティング後、該コーティングを一旦中断し、カソード電極９上の基板保持盤１を反転して配置し、つまり裏面１ｂを上向きに配置し、エッジ２とピン３と凹部４を下向きに配置した後、反応器８内のプラズマ１０化とＤＬＣ膜コーティングを再開し、吸引孔６の内面を含む基板保持盤１の裏面１ｂと側面１ｃ周面にＤＬＣ膜コーティングする。
この場合、基板保持盤１を反転する代わりに、基板保持盤１を回転させながら表裏両面にＤＬＣ膜コーティングすることも可能であり、その場合は基板保持盤１の保持部におけるＤＬＣ膜コーティングに対応する必要がある。 Then, after coating the DLC film with a predetermined thickness on the peripheral surface, the coating is temporarily interrupted, the substrate holding plate 1 on the cathode electrode 9 is inverted and arranged, that is, the back surface 1b is arranged upward, After the pins 3 and the recesses 4 are disposed downward, the plasma 10 in the reactor 8 and the DLC film coating are restarted, and the DLC film is formed on the peripheral surface of the back surface 1b and the side surface 1c of the substrate holder 1 including the inner surface of the suction hole 6. Coating.
In this case, instead of inverting the substrate holder 1, it is also possible to coat the DLC film on both the front and back surfaces while rotating the substrate holder 1. In this case, DLC film coating on the holding part of the substrate holder 1 is supported. There is a need to.

このように基板保持盤１を反転し、その表面１ａ側と裏面１ｂ側から前後二回に亘ってＤＬＣ膜コーティングすることによって、吸引孔６の内面を精密にＤＬＣ膜コーティングできるとともに、側面１ｃ周面を前後二回に亘ってＤＬＣ膜コーティングすることによって、当該部のＤＬＣ膜７ａを他の表面１ａ側周面および裏面１ｂのＤＬＣ膜７よりも容易かつ安価に肉厚に形成できるとともに、露光時に側面１ｃから基板保持盤１へ入射する光を抑制し、基板保持盤１表面の低反射率を維持できる。 In this way, by reversing the substrate holding plate 1 and coating the DLC film twice in front and rear from the front surface 1a side and the back surface 1b side, the inner surface of the suction hole 6 can be precisely coated with the DLC film, and the side surface 1c By coating the surface with the DLC film twice before and after, the DLC film 7a of the part can be easily and cheaply formed thicker than the DLC film 7 on the other surface 1a side peripheral surface and the back surface 1b, and exposure Sometimes, light incident on the substrate holder 1 from the side surface 1c can be suppressed, and the low reflectance of the surface of the substrate holder 1 can be maintained.

そして、側面１ｃのＤＬＣ膜７ａを他の表面のＤＬＣ膜７よりも肉厚に形成することによって、他の表面のＤＬＣ膜７の薄膜化を促がし、当該部のＤＬＣ膜７のコーティングの合理化と低廉化を図れる。
実施形態では基板保持盤１の表面１ａ側周面と裏面１ｂのＤＬＣ被膜の膜厚を３μｍ以下に形成し、側面１ｃ周面のＤＬＣ被膜の膜厚を前記部位の膜厚以上の３〜６μｍに形成している。 Then, by forming the DLC film 7a on the side surface 1c thicker than the DLC film 7 on the other surface, the thinning of the DLC film 7 on the other surface is promoted, and the coating of the DLC film 7 on the relevant part is promoted. Streamline and reduce costs.
In the embodiment, the film thickness of the DLC film on the front surface 1a side surface and the back surface 1b of the substrate holder 1 is 3 μm or less, and the film thickness of the DLC film on the side surface 1c is 3 to 6 μm, which is equal to or greater than the film thickness of the above part. Is formed.

この後、少なくとも前記基板保持盤１の表面１ａ側の表面、つまりエッジ２とピン３と凹部４周面のＤＬＣ被膜上に無機透明の薄膜１１を形成している。
前記薄膜１１は、基板保持盤１の全表面にＤＬＣ膜コーティング後、基板保持盤１の表面１ａ側の表面に、硬化被膜が透明になる低粘性コート剤を塗布して形成され、その膜厚を２μｍ以下に形成している。したがって、薄膜１１による基板保持盤１の平面度の悪化の懸念が無く、顕著な反射率低減が可能である。
実施形態では前記コート剤として、アルコキシシラン化合物を含むものやシロキサン系の無機系コート剤を使用し、基板保持盤１の表面１ａ側の表面に硬化被膜の無機透明の薄膜１１を形成している。 Thereafter, an inorganic transparent thin film 11 is formed at least on the surface of the substrate holding plate 1 on the surface 1a side, that is, on the DLC film on the peripheral surface of the edge 2, the pin 3, and the recess 4.
The thin film 11 is formed by coating a DLC film on the entire surface of the substrate holder 1 and then applying a low-viscosity coating agent on the surface 1a side of the substrate holder 1 so that the cured film is transparent. Is formed to be 2 μm or less. Therefore, there is no concern about the deterioration of the flatness of the substrate holder 1 due to the thin film 11, and a significant reduction in reflectance is possible.
In the embodiment, as the coating agent, an alkoxysilane compound-containing one or a siloxane-based inorganic coating agent is used, and an inorganic transparent thin film 11 of a cured coating is formed on the surface 1 a side of the substrate holder 1. .

次に、発明者は構成を異にした種々の基板保持盤１を製作し、それらの平面度や反射率、製作コストを比較して、最良の基板保持盤１を採択した。
先ず、実験例１の基板保持盤１は、図４（ａ）のように表面１ａ側のみに膜厚３μｍのＤＬＣ膜７をコーティングし、それらの表面には薄膜１１をコーティングせず、また側面１ｃと吸引孔６内にＤＬＣ膜７をコーティングしていない。 Next, the inventor manufactured various substrate holding plates 1 having different configurations, and compared the flatness, reflectivity, and manufacturing cost thereof, and adopted the best substrate holding plate 1.
First, as shown in FIG. 4 (a), the substrate holder 1 of Experimental Example 1 is coated with a DLC film 7 having a film thickness of 3 μm only on the surface 1a side, and the thin film 11 is not coated on the surface. The DLC film 7 is not coated in 1c and the suction hole 6.

実験例２の基板保持盤１は、図４（ｂ）のように表面１ａ側と裏面１ｂ側に膜厚３μｍのＤＬＣ膜７をコーティングし、それらの表面には薄膜１１をコーティングせず、また側面１ｃに膜厚４〜６μｍのＤＬＣ膜７をコーティングし、吸引孔６内に膜厚２〜６μｍのＤＬＣ膜７をコーティングしている。
実験例３の基板保持盤１は、図４（ｃ）のように表面１ａ側と裏面１ｂ側に膜厚３μｍのＤＬＣ膜７をコーティングし、それらの表面に極薄の薄膜１１をコーティングするとともに、側面１ｃに膜厚４〜６μｍのＤＬＣ膜７をコーティングし、吸引孔６内に膜厚２〜６μｍのＤＬＣ膜７をコーティングしている。 As shown in FIG. 4B, the substrate holder 1 of Experimental Example 2 is coated with a DLC film 7 having a film thickness of 3 μm on the front surface 1a side and the back surface 1b side, and the front surface is not coated with the thin film 11; The side surface 1c is coated with a DLC film 7 having a film thickness of 4 to 6 μm, and the suction hole 6 is coated with a DLC film 7 having a film thickness of 2 to 6 μm.
As shown in FIG. 4C, the substrate holder 1 of Experimental Example 3 is coated with a DLC film 7 having a film thickness of 3 μm on the front surface 1a side and the back surface 1b side, and an extremely thin thin film 11 is coated on these surfaces. The side surface 1c is coated with a DLC film 7 having a film thickness of 4 to 6 μm, and the suction hole 6 is coated with a DLC film 7 having a film thickness of 2 to 6 μm.

実験例４の基板保持盤１は、図４（ｄ）のように表面１ａ側と裏面１ｂ側に膜厚１０μｍのＤＬＣ膜７をコーティングし、それらの表面に極薄の薄膜１１をコーティングするとともに、側面１ｃに膜厚５〜２０μｍのＤＬＣ膜７をコーティングし、吸引孔６内に膜厚５〜２０μｍのＤＬＣ膜７をコーティングし、全体的にＤＬＣ膜７を肉厚にしている。
実験例５の基板保持盤１は、拡大して示した図４（ｅ）のように表面１ａ側と裏面１ｂ側に膜厚１μｍのＤＬＣ膜７をコーティングし、それらの表面に極薄の薄膜１１をコーティングするとともに、側面１ｃに膜厚１．５〜２μｍのＤＬＣ膜７ａをコーティングし、吸引孔６内に膜厚１〜２μｍのＤＬＣ膜７をコーティングし、全体的にＤＬＣ膜７を肉薄にしている。 As shown in FIG. 4D, the substrate holder 1 of Experimental Example 4 is coated with a DLC film 7 having a film thickness of 10 μm on the front surface 1a side and the back surface 1b side, and an extremely thin thin film 11 is coated on these surfaces. The DLC film 7 having a film thickness of 5 to 20 μm is coated on the side surface 1c, and the DLC film 7 having a film thickness of 5 to 20 μm is coated in the suction hole 6 so that the DLC film 7 is made thick as a whole.
As shown in FIG. 4 (e), the substrate holding plate 1 of Experimental Example 5 is coated with a DLC film 7 having a thickness of 1 μm on the front surface 1a side and the back surface 1b side, and an extremely thin thin film is formed on these surfaces. 11, the side surface 1 c is coated with a DLC film 7 a having a film thickness of 1.5 to 2 μm, the DLC film 7 having a film thickness of 1 to 2 μm is coated in the suction hole 6, and the DLC film 7 is thinned as a whole. I have to.

こうして製作した５種類の基板保持盤１に対し、平面度と波長３６０〜７４０ｎｍに亘る反射率を測定する。
この場合、平面度測定にはミツトヨ製三次元測定器（ＲＶＡ１５００Ａ）を使用し、基材表面のエッジ部およびピン先端部を合計２０箇所測定した。また、反射率測定にはコニカミノルタ製分光側色計ＣＭ−２６００ｄを使用して表面側の１０箇所について、全反射率および拡散反射率を測定した。 The flatness and the reflectance over a wavelength range of 360 to 740 nm are measured for the five types of substrate holders 1 thus manufactured.
In this case, a Mitutoyo three-dimensional measuring instrument (RVA1500A) was used for the flatness measurement, and a total of 20 edges and pin tips were measured on the substrate surface. Further, for the reflectance measurement, the total reflectance and the diffuse reflectance were measured at 10 points on the surface side using a spectroscopic color meter CM-2600d manufactured by Konica Minolta.

前記反射率の結果は表１の通りで、正反射成分と拡散反射成分を足し合わせた全全反射率の測定結果は図５の通りである。
このうち、反射率は表面側の薄膜１１のコーティングの有無によって、反射率が大きく変化し、薄膜１１がコーティングされている、例えば実験例３が、コーティングされていない、例えば実験例２に比べて、反射率が著しく改善されていることが分かる。
また、全反射率は図５のように、実験例３が波長３６０〜７２０ｎｍの全域に亘って約４％を維持し、実験例２が約８％であるのに比べて非常に低く、従来技術（特許文献５）と比べても３６０〜５００ｎｍの範囲で大幅に反射率を低下できる結果を得られた。 The result of the reflectance is as shown in Table 1, and the measurement result of the total total reflectance obtained by adding the regular reflection component and the diffuse reflection component is as shown in FIG.
Of these, the reflectivity varies greatly depending on the presence or absence of coating of the thin film 11 on the surface side, and the thin film 11 is coated, for example, Experimental Example 3 is not coated, for example, compared to Experimental Example 2, for example. It can be seen that the reflectance is remarkably improved.
Further, as shown in FIG. 5, the total reflectance is about 4% in the experimental example 3 over the entire wavelength range of 360 to 720 nm, and is very low compared with the experimental example 2 of about 8%. Even when compared with the technique (Patent Document 5), the reflectance can be significantly reduced in the range of 360 to 500 nm.

このことから薄膜１１のコーティングが有利であると考えられる。これは薄膜１１とＤＬＣ膜７の二重皮膜を入射光が伝播する際の屈折に原因していると考えられる。
製造コストは、ＤＬＣ膜７の肉厚ないしその塗布作業の手間に関係し、ＤＬＣ膜７が肉厚のものが薄肉のものよりも高いことが分かる。
これらの結果を実験例毎にまとめて総合評価したところ、次のような結果を得た。

From this, it is considered that the coating of the thin film 11 is advantageous. This is considered to be caused by refraction when incident light propagates through the double film of the thin film 11 and the DLC film 7.
It can be seen that the manufacturing cost is related to the thickness of the DLC film 7 or the time for applying the DLC film 7, and that the DLC film 7 is thicker than the thin one.
When these results were collectively evaluated for each experimental example, the following results were obtained.

こうして平面度と反射率と製造コストを総合評価すると、実験例３が最も良い結果を得られた。実験例３を再掲すると次のようである。
表面１ａ側と裏面１ｂ側に膜厚３μｍのＤＬＣ膜７をコーティングし、それらの表面に極薄の薄膜１１をコーティングし、側面１ｃに膜厚４〜６μｍのＤＬＣ膜７ａをコーティングし、吸引孔６内に膜厚２〜６μｍのＤＬＣ膜７をコーティングする。
前記実験例３を前記実施形態と比較すると、両者は側面１ｃのＤＬＣ膜７ａの膜厚以外は共通し、ただ実施形態の側面１ｃのＤＬＣ膜７ａの膜厚が３〜６μｍであるのに対し、実験例３のそれは４〜６μｍであり、その範囲が僅かに狭くなっているが、概ね両者の構成は同一である、といえる。 Thus, when the flatness, reflectance, and manufacturing cost were comprehensively evaluated, Experimental Example 3 gave the best results. Experimental example 3 is shown again as follows.
The surface 1a side and the back surface 1b side are coated with a DLC film 7 having a film thickness of 3 μm, the surface is coated with a very thin thin film 11, and the side surface 1c is coated with a DLC film 7a having a film thickness of 4 to 6 μm. 6 is coated with a DLC film 7 having a film thickness of 2 to 6 μm.
Comparing the experimental example 3 with the above embodiment, both are common except for the thickness of the DLC film 7a on the side surface 1c, whereas the thickness of the DLC film 7a on the side surface 1c of the embodiment is 3 to 6 μm. In Experimental Example 3, it is 4 to 6 μm, and the range is slightly narrow, but it can be said that the configurations of both are almost the same.

このように構成した液晶基板保持盤は、母材を透明な石英ガラスとしたから、軽量で液晶基板サイズないし基板ステ−ジの大型化に伴なう基板保持盤１の大型化に対応できるとともに、熱変形が極めて小さく、露光装置においては露光精度の低下を防止することもできる。
また、検査装置においては、保持盤に起因する反射光の強度が低く、検査基板の欠陥に起因するコントラストの変化を確実に検出できるとともに、反射光のコントラストの変化を抑制し、擬似的な傷や異物等の検出を未然に防止し、検査精度を向上し得る。 Since the liquid crystal substrate holding disk constructed as described above is made of transparent quartz glass as a base material, it is lightweight and can cope with the increase in size of the liquid crystal substrate or the increase in the size of the substrate holding disk 1 due to the increase in the substrate stage. Further, thermal deformation is extremely small, and it is possible to prevent a reduction in exposure accuracy in the exposure apparatus.
In addition, in the inspection apparatus, the intensity of the reflected light caused by the holding plate is low, and it is possible to reliably detect a change in contrast due to a defect in the inspection substrate, and to suppress a change in the contrast of the reflected light, resulting in a pseudo flaw. The detection accuracy can be improved by preventing the detection of foreign matter and foreign matters.

しかも、基板保持盤１の表面と吸引孔６の内面に耐摩耗性と摺動性に優れるＤＬＣ膜７，７ａをコーティングしたから、経年的な使用による摩耗を抑制し、基板５の長期に亘る円滑な移動を促がし、基板５の脱着を容易かつ速やかに行なえる。
したがって、従来のセラミックス製のように、焼結時の収縮や割れを生じ易くて歩留まりが悪かったり、またアルミニウムにブラックアルマイトをコーティングしたもののように、熱変形によって露光精度が低下するとともに、経年的な使用によってブラックアルマイトが摩耗し、反射率が変化する不具合から解消される。 In addition, since the surface of the substrate holder 1 and the inner surface of the suction hole 6 are coated with the DLC films 7 and 7a having excellent wear resistance and slidability, wear due to aging is suppressed, and the substrate 5 is kept for a long time. Smooth movement is promoted, and the substrate 5 can be easily and quickly attached and detached.
Therefore, shrinkage and cracking are likely to occur during sintering as in the case of conventional ceramics, resulting in poor yields, and exposure accuracy decreases due to thermal deformation, such as when aluminum is coated with black alumite. The anodized black anodized wears away from the problem of changing reflectance.

更に、基板保持盤１は全面をＤＬＣ膜コーティングしたから、表面側のＤＬＣ膜コーティングがトラブルまたは劣化により剥離しても、他部位のＤＬＣ膜によって反射率は上昇することなく低反射率を維持できるため、直ちに装置を停止して基板保持盤を交換する必要がない。したがって、新たな基盤保持盤を準備している間も装置を稼働し得るから、装置稼働率の大幅な向上と生産性の向上を図れる。 Further, since the entire surface of the substrate holding plate 1 is coated with the DLC film, even if the DLC film coating on the surface side is peeled off due to trouble or deterioration, the DLC film at the other part can maintain the low reflectance without increasing the reflectance. Therefore, it is not necessary to immediately stop the apparatus and replace the substrate holding plate. Therefore, since the apparatus can be operated while preparing a new base holding panel, the apparatus operating rate can be greatly improved and the productivity can be improved.

前記基板保持盤１を製作する場合は、先ず透明な石英ガラスのインゴットを切断し、これを基板保持盤１を形成可能な寸法の矩形板状に切り出す。
この状況は図３（ａ）のようで、前記切断をダイヤモンド砥粒を固着した金属ブレードを用い、または切削油等の流体中に砥粒を混在させ、これをノズルから高速で噴射させて行なう。 When the substrate holding plate 1 is manufactured, first, a transparent quartz glass ingot is cut, and the substrate holding plate 1 is cut into a rectangular plate having a size capable of forming the substrate holding plate 1.
This situation is as shown in FIG. 3 (a), and the cutting is performed by using a metal blade with diamond abrasive grains fixed thereto or by mixing abrasive grains in a fluid such as cutting oil and injecting the abrasive grains from a nozzle at a high speed. .

次に、前記切り出した石英ガラス板の表裏両面を研削加工し、所望の厚さに精密に加工するとともに、それらの両面を所定の平面度と平坦度に加工し、この石英ガラス板に吸引孔６を形成する。この状況は図３（ｂ）のようである。
この後、石英ガラス板の表面１ａをサンドブラストおよび研削加工して、外周にエッジ２を形成し、その内側に多数のピン３と凹部４を形成する。この状況は図１および図２、図３（ｃ）のようである。 Next, both the front and back sides of the cut quartz glass plate are ground and precisely processed to a desired thickness, and both sides are processed to a predetermined flatness and flatness, and suction holes are formed in the quartz glass plate. 6 is formed. This situation is as shown in FIG.
Thereafter, the surface 1a of the quartz glass plate is sandblasted and ground to form an edge 2 on the outer periphery, and a large number of pins 3 and recesses 4 are formed on the inside. This situation is as shown in FIGS. 1, 2, and 3 (c).

そして、前記基板保持盤１の全周面、すなわち表面１ａ側のエッジ２とピン３と凹部４の全周面、および裏面１ｂの全周面と側面１ｃの全周面、吸引孔６の内面全面に耐磨耗性と摺動性に優れるＤＬＣ膜７，７ａをコーティングする。
前記コーティングは、側面１ｃの全周面を除くＤＬＣ膜７の膜厚を１０μｍ以下、実施形態では３μｍ以下に形成し、側面１ｃの全周面のＤＬＣ膜７ａの膜厚を３〜６μｍに形成し、側面１ｃのＤＬＣ膜７ａを他のＤＬＣ膜７よりも肉厚に形成する。 Then, the entire peripheral surface of the substrate holder 1, that is, the peripheral surface of the edge 2, the pin 3 and the recess 4 on the front surface 1 a side, the entire peripheral surface of the back surface 1 b and the side surface 1 c, and the inner surface of the suction hole 6. The entire surface is coated with DLC films 7 and 7a having excellent wear resistance and sliding properties.
In the coating, the DLC film 7 excluding the entire peripheral surface of the side surface 1c is formed to have a thickness of 10 μm or less, and in the embodiment, 3 μm or less, and the DLC film 7a on the entire peripheral surface of the side surface 1c is formed to have a thickness of 3 to 6 μm. Then, the DLC film 7 a on the side surface 1 c is formed thicker than the other DLC films 7.

前記ＤＬＣ膜７，７ａは、基板保持盤１に対するピン３と凹部４と吸引孔６の形成後、プラズマＣＶＤ法によってコーティングする。
すなわち、前記各部を形成した基板保持盤１を反応器８に搬入し、これを反応器８内に配置したカソ−ド電極９に載置し、このカソ−ド電極９と対向配置したアノ−ド電極（図示略）間に高周波電圧を印加する。
これと同時に反応器８の入口側（図示略）から、例えば原料ガスであるメタンを供給して原料ガスをプラズマ１０化し、反応器８内部のガスを出口側（図示略）から真空ポンプ（図示略）で排出する。 The DLC films 7 and 7a are coated by the plasma CVD method after the pins 3, the recesses 4 and the suction holes 6 are formed on the substrate holder 1.
That is, the substrate holding plate 1 in which each of the above parts is formed is carried into a reactor 8 and placed on a cathode electrode 9 disposed in the reactor 8, and an anode disposed opposite to the cathode electrode 9. A high frequency voltage is applied between the two electrodes (not shown).
At the same time, for example, methane, which is a raw material gas, is supplied from the inlet side (not shown) of the reactor 8 to turn the raw material gas into a plasma 10, and the gas inside the reactor 8 is vacuum pumped (not shown) from the outlet side (not shown). Omitted).

このようにして、原料ガスのメタンを分解し、分解した炭素をカソード電極９上の基板保持盤１に付着させＤＬＣ膜７を堆積して、凹部４と吸引孔６の内面を含む基板保持盤１の表面１ａ側周面と、側面１ｃ周面にＤＬＣ膜コーティングする。この状況は図３（ｄ）のようである。 In this way, the source gas methane is decomposed, the decomposed carbon is attached to the substrate holding plate 1 on the cathode electrode 9 to deposit the DLC film 7, and the substrate holding plate including the recess 4 and the inner surface of the suction hole 6 is deposited. DLC film coating is performed on the surface 1a side peripheral surface of 1 and the side surface 1c peripheral surface. This situation is as shown in FIG.

そして、前記周面に所定膜厚のＤＬＣ膜コーティング後、該コーティングを一旦中断し、カソ−ド電極１０上の基板保持盤１を反転して配置し、つまり裏面１ｂを上向きに配置し、エッジ２とピン３と凹部４を下向きに配置した後、反応器８内のプラズマ１０化とＤＬＣ膜コーティングを再開し、吸引孔６の内面を含む基板保持盤１の裏面１ｂと側面１ｃ周面にＤＬＣ膜コーティングする。この状況は図３（ｅ）,（ｆ）のようである。
この場合、基板保持盤１を反転する代わりに、基板保持盤１を回転させながら表裏両面にＤＬＣ膜コーティングすることも可能であり、その場合は基板保持盤１の保持部におけるＤＬＣ膜コーティングの欠損部に対処する。 Then, after coating the DLC film with a predetermined film thickness on the peripheral surface, the coating is temporarily interrupted, and the substrate holding plate 1 on the cathode electrode 10 is inverted and arranged, that is, the back surface 1b is arranged upward, the edge 2, the pin 3, and the concave portion 4 are disposed downward, and then the plasma 10 in the reactor 8 is converted to plasma 10 and the DLC film coating is resumed, and the back surface 1 b and the side surface 1 c of the substrate holding plate 1 including the inner surface of the suction hole 6. DLC film coating. This situation is as shown in FIGS.
In this case, instead of inverting the substrate holding plate 1, it is also possible to coat the DLC film on both the front and back surfaces while rotating the substrate holding plate 1. In this case, the DLC film coating defect in the holding part of the substrate holding plate 1 is possible. Deal with the department.

このように基板保持盤１を反転し、その表面１ａ側と裏面１ｂ側から前後二回に亘ってＤＬＣ膜コーティングすることによって、吸引孔６の内面を精密にＤＬＣ膜コーティングできる。
また、側面１ｃ周面を前後二回に亘ってＤＬＣ膜コーティングすることによって、当該部のＤＬＣ膜７ａを、他の表面１ａ側周面および裏面１ｂのＤＬＣ膜７よりも肉厚に形成でき、他の表面１ａ側周面および裏面１ｂのＤＬＣ膜７の膜厚の薄膜化を図れるから、当該部のＤＬＣ膜コーティングを合理的かつ安価に行なえる。 In this way, by inverting the substrate holder 1 and coating the DLC film twice in the front and rear directions from the front surface 1a side and the back surface 1b side, the inner surface of the suction hole 6 can be precisely coated with the DLC film.
In addition, by coating the peripheral surface of the side surface 1c twice before and after, the DLC film 7a of the part can be formed thicker than the DLC film 7 on the other surface 1a side peripheral surface and the back surface 1b, Since the film thickness of the DLC film 7 on the other peripheral surface of the front surface 1a and the back surface 1b can be reduced, the DLC film coating of the part can be performed reasonably and inexpensively.

このように側面１ｃのＤＬＣ膜７ａを肉厚に形成することによって、露光時に側面１ｃから基板保持盤１へ入射する光を抑制し、基板保持盤１表面の低反射率を維持して良好な露光作用を奏する。その際、吸引孔６の内面もＤＬＣ膜コーティングされているから、基板保持盤１表面の低反射率化を促す。 By forming the DLC film 7a on the side surface 1c thick in this way, light incident on the substrate holding plate 1 from the side surface 1c at the time of exposure is suppressed, and the low reflectance on the surface of the substrate holding plate 1 is maintained and good. Exhibits exposure. At this time, since the inner surface of the suction hole 6 is also coated with the DLC film, the surface of the substrate holding plate 1 is promoted to have a low reflectance.

こうして製作した基板保持盤１を用いて基板５を露光する場合は、基板保持盤１を露光装置（図示略）の基板ステージ（図示略）上に配置し、その吸引孔６を真空ポンプ（図示略）に連通し、表面１ａ側に基板５を載置して真空ポンプを作動し、ピン３と凹部４周辺の空気を吸引して当該スペースを減圧し、基板５を保持する。
この状況の下で基板５の上方から露光光を照射し、これを投影光学系を介して基板５に入射し、所定のパターン像を基板５に結像する。
その際、基板５を透過した露光光の一部が基板保持盤１の表面１ａに到達し、その一部が前記表面１ａで反射して基板５に入射し、二重露光を引き起こす可能性がある。 When the substrate 5 is exposed using the substrate holder 1 thus manufactured, the substrate holder 1 is placed on a substrate stage (not shown) of an exposure apparatus (not shown), and the suction hole 6 is vacuum pumped (not shown). The substrate 5 is placed on the surface 1a side, the vacuum pump is operated, the air around the pins 3 and the recesses 4 is sucked to decompress the space, and the substrate 5 is held.
Under this condition, exposure light is irradiated from above the substrate 5, and this is incident on the substrate 5 through the projection optical system, and a predetermined pattern image is formed on the substrate 5.
At that time, a part of the exposure light transmitted through the substrate 5 reaches the surface 1a of the substrate holder 1 and a part of the exposure light may be reflected by the surface 1a and incident on the substrate 5 to cause double exposure. is there.

この場合、実施形態の基板保持盤１の表面１ａはＤＬＣ膜７と薄膜１１とで被覆され、当該部の全反射率は５%以下で僅少であるから、前記反射光の入射を抑制し二重露光を防止する。
その際、基板５の外周部で露光光が散乱し、この散乱光と基板保持盤１の外部の光が側面１ｃから内部に入射し得るが、側面１ｃのＤＬＣ膜７ａは他の部位のＤＬＣ膜７よりも肉厚であるから、前記入射を抑制する。
しかも、吸引孔６の内面にはＤＬＣ膜７が被覆され、吸引孔６を透過して表面１ａ側へ伝播する入射光を遮蔽するから、基板保持盤１の表面１ａにおける反射光を抑制する。 In this case, the surface 1a of the substrate holding plate 1 according to the embodiment is covered with the DLC film 7 and the thin film 11, and the total reflectance of the portion is 5% or less, so that the incidence of the reflected light is suppressed. Prevent heavy exposure.
At that time, the exposure light is scattered at the outer peripheral portion of the substrate 5 and the scattered light and the light outside the substrate holder 1 can enter the inside from the side surface 1c. Since it is thicker than the film 7, the incidence is suppressed.
In addition, the inner surface of the suction hole 6 is covered with the DLC film 7 and shields the incident light that passes through the suction hole 6 and propagates to the surface 1a side, so that the reflected light on the surface 1a of the substrate holder 1 is suppressed.

このようにして基板保持盤１の表面１ａにおける反射率が低下され、前記表面１ａにおける反射が抑制されて、前記二重露光の発生を阻止し良好かつ安定した露光を実現する。また、検査装置においては、保持盤からの反射光強度が低いため、保持盤起因のコントラスト変化を無視することができ、検査基板に起因する欠陥を精度良く検出し検査精度を向上することができる。 In this way, the reflectance on the surface 1a of the substrate holder 1 is lowered, the reflection on the surface 1a is suppressed, the occurrence of the double exposure is prevented, and good and stable exposure is realized. Further, in the inspection apparatus, since the intensity of reflected light from the holding plate is low, the contrast change caused by the holding plate can be ignored, and the defect caused by the inspection substrate can be detected with high accuracy and the inspection accuracy can be improved. .

このように本発明の液晶基板保持盤は、基板保持盤の全周面にＤＬＣ（ダイヤモンドライクカーボン）膜を被覆し、基板載置面の摩耗を防止し基板の摺動を円滑にするとともに、側面のＤＬＣ膜の膜厚を他部位周面よりも厚く形成して、露光または検査時に側面から基板保持盤へ入射する光を抑制し基板載置面の低反射率を維持して、露光装置ないし検査装置の大型化と表面の低反射率化を図るとともに、他部位周面のＤＬＣ膜の膜厚を薄膜化して、ＤＬＣ膜コーティングの合理化と低廉化を図り安価に製作できるから、例えば液晶パネルまたはウェーハの露光装置用ないし検査装置用の基板を保持する基板保持盤に好適である。 Thus, the liquid crystal substrate holding disk of the present invention covers the entire peripheral surface of the substrate holding disk with a DLC (diamond-like carbon) film, prevents wear of the substrate mounting surface and makes the substrate slide smoothly, An exposure apparatus that forms the DLC film on the side surface thicker than the peripheral surface of other parts, suppresses light incident on the substrate holding plate from the side surface during exposure or inspection, and maintains the low reflectance of the substrate mounting surface. In addition to increasing the size of the inspection device and lowering the reflectance of the surface, the thickness of the DLC film on the peripheral surface of other parts can be reduced, and the DLC film coating can be rationalized and reduced in cost. It is suitable for a substrate holding plate for holding a substrate for a panel or wafer exposure apparatus or inspection apparatus.

１母材（基板保持盤）
１ａ母材表面
１ｂ裏面
１ｃ側面
３ピン
４凹部
５基板
６吸引孔
７，７ａＤＬＣ膜
１１薄膜 1 Base material (board holding board)
1a Base material surface 1b Back surface 1c Side surface 3 Pin 4 Recess 5 Substrate 6 Suction hole 7, 7a DLC film 11 Thin film

Claims

The base material surface to form a plurality of pins and recesses and the suction holes, the entire peripheral surface of the base metal surface and the back surface and the side surface and the inner surface of the suction holes and DLC (diamond-like carbon) coating film of the DLC film of the side In the substrate holding plate formed with a thickness thicker than the DLC film on the peripheral surface other than the side surface, a transparent thin film is coated on the DLC film on the base material surface side including at least the pin and the recess. Board holding board.

The substrate holder according to claim 1 , wherein the thickness of the thin film is 2 μm or less .

Substrate holding plate according to claim 1, wherein the total reflectivity was less than 5% of the base material surface.