JP2008181010A - Substrate position adjusting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate position adjusting system that can adjust relative positions between a substrate and a photomask with high accuracy without obstructing display even when an alignment mark is provided in the effective display area of the substrate. <P>SOLUTION: The substrate position adjusting system includes an imaging means to optically image an alignment mark formed on a substrate, an image optimizing means to optimize the obtained image, and an alignment adjusting means to finely adjust the alignment of the substrate based on the image information. The imaging means comprises inserting the substrate into between a pair of polarizing plates, projecting light through one of the polarizing plates and imaging the alignment mark through the other polarizing plate. The image optimizing means rotates at least one of the pair of polarizing plates around the optical axis so as to maximize the contrast of the imaged alignment mark. The alignment adjusting means finely adjusts the position of the substrate based on the optimized image information. The alignment mark is made of a liquid crystal material. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

Field of Invention

  The present invention relates to a substrate position adjustment system that can adjust the relative position between a substrate and a photomask with high accuracy without disturbing display even when an alignment mark is provided in an effective display area of the substrate.

  In the manufacture of semiconductors and electronic displays, in recent years, a fine patterning technique by exposure through a photomask, so-called photolithography, has become an indispensable technique. For example, a color filter is an important member that determines the color display performance of a liquid crystal display, and a fine pattern composed of three primary colors of red (R), green (G), and blue (B) is formed on a glass substrate. is there. For the patterning of each member constituting the color filter, a photolithography method capable of high-definition and high-resolution patterning is preferably used.

  The photolithographic method is performed by exposing a resist coated on a crow substrate through a photomask. Since the pattern formed on the base material is determined by the relative position between the photomask and the base material, it is necessary to strictly align the substrate and the photomask.

  The alignment between the substrate and the photomask is proposed in JP-A-1-293304 (Patent Document 1), JP-A-2-89004 (Patent Document 2) and JP-A-2-160202 (Patent Document 3). In general, by adjusting the relative positions of the substrate and the photomask by visually observing each other or mechanically recognizing the alignment marks provided on the substrate and the photomask facing each other. Done.

  Usually, such an alignment mark is formed by a pattern having a certain shape that reflects or absorbs light from a light source. For example, in the plate making process of the color filter, first, a black matrix and an alignment mark are simultaneously formed on the substrate. At this time, the relative position of the black matrix region serving as an effective display portion is not uniformly determined with respect to the base material to be configured, but the relative position with the alignment mark is uniformly determined by the design of the photomask. Is. The subsequent formation of the RGB coloring pattern is performed by adjusting the position together with the alignment mark formed on the photomask with reference to the alignment mark previously formed together with the black matrix, and performing exposure. .

  As the alignment mark, a light-shielding or reflective sign is usually used. However, it is necessary to be able to optically recognize the shape of a reflection pattern or a transmission pattern. Therefore, as the alignment mark provided on the substrate, a chromium thin film or an aluminum thin film that can be used for both reflection and transmission, or a resin black film that can be used mainly in the transmission mode is used.

Such an alignment mark is indispensable when positioning the substrate and the photomask. However, when assembled as a liquid crystal display device, the alignment mark usually hinders display. It is provided outside the effective area. Therefore, since it is necessary to provide a color filter layer on the substrate in consideration of the alignment mark formation location outside the effective display area, it is necessary to use a substrate having a margin around the effective display area.
JP-A-1-293304 JP-A-2-89004 JP-A-2-160202

  The inventors use a liquid crystal material that causes a phase difference as an alignment mark, and uses an imaging unit that can recognize the alignment mark only through the polarizing plate, thereby aligning the effective display area of the substrate. It was found that the substrate and the photomask can be positioned with high accuracy without hindering the display even when the mark is provided. The present invention is based on this finding.

  Therefore, an object of the present invention is to provide a substrate position adjustment system capable of adjusting the relative position between the substrate and the photomask with high accuracy without disturbing the display even when the alignment mark is provided in the effective display area of the substrate. Is to provide.

A substrate position adjustment system according to the present invention includes an imaging unit that optically images an alignment mark formed on a substrate, an image optimization unit that optimizes the captured image, and the substrate based on the image information. In a substrate position adjustment system comprising an alignment adjustment means for performing an alignment fine adjustment operation,
The imaging means sandwiches a substrate between a pair of polarizing plates, projects light from one polarizing plate side, and images an alignment mark from the other polarizing plate side,
The image optimization means rotates at least one of the pair of polarizing plates around the optical axis so as to maximize the contrast of the captured alignment mark,
The alignment adjustment means performs fine adjustment of the position of the substrate based on the optimized image information,
The alignment mark is made of a liquid crystal material.

  In the above aspect, the pair of polarizing plates are arranged so as to be in a parallel Nicol state, and the pair of polarizing plates rotate around the optical axis while maintaining the parallel Nicol state. preferable.

Further, a substrate position adjustment system as another aspect of the present invention includes an imaging unit that optically images an alignment mark formed on a substrate, an image optimization unit that optimizes the captured image, and In a substrate position adjustment system comprising alignment adjustment means for performing an alignment fine adjustment operation of the substrate based on image information,
The imaging means projects light onto the substrate through the polarizing plate from the imaging position side, reflects light transmitted through the substrate by a light reflecting plate provided on the surface of the substrate opposite to the projection surface, and The upper alignment mark is imaged,
The image optimization means rotates the polarizing plate around the optical axis so as to maximize the contrast of the captured alignment mark,
The alignment adjustment means performs fine adjustment of the substrate position based on the optimized image information;
The alignment mark is made of a liquid crystal material.

  In the substrate position adjustment system, the alignment mark is preferably formed in the effective display area of the substrate.

  In the substrate position adjusting system according to the present invention, it is preferable that the liquid crystal material includes a nematic liquid crystal material fixed in a uniaxial orientation.

  The substrate position adjustment system according to the present invention can be preferably applied to photolithography used for patterning of color filters and the like.

  Further, the substrate position adjusting system according to the present invention can be suitably applied to substrate cutting processing and bonding processing between substrates.

Furthermore, the substrate position adjusting method according to another aspect of the present invention optically images an alignment mark formed on the substrate, optimizes the captured image, and based on the optimized image information, In the substrate position adjustment method for performing the substrate alignment fine adjustment operation,
The imaging is performed by inserting a substrate between a pair of polarizing plates, projecting light from one polarizing plate side, and imaging an alignment mark from the other polarizing plate side,
Performing optimization of the image by rotating at least one of the pair of polarizing plates around the optical axis so that the contrast of the captured alignment mark is maximized,
The alignment mark is made of a liquid crystal material.

  In the above aspect, it is preferable that the pair of polarizing plates are arranged so as to be in a parallel Nicol state, and the pair of polarizing plates rotate around the optical axis while maintaining the parallel Nicol state.

Further, the substrate position adjusting method as another aspect of the present invention is based on the optimized image information by optically imaging the alignment mark formed on the substrate and optimizing the captured image. In the substrate position adjustment method for performing the fine alignment operation of the substrate,
The image is projected onto the substrate through the polarizing plate from the imaging position side, and the light transmitted through the substrate is reflected by the light reflecting plate provided on the surface of the substrate opposite to the light projecting surface. By imaging the alignment mark of
Performing the optimization of the image by rotating the polarizing plate around the optical axis so as to maximize the contrast of the captured alignment mark,
The alignment mark is made of a liquid crystal material.

  In the substrate position adjusting method according to the present invention, a photomask is inserted between the substrate and the polarizing plate, and the substrate is determined depending on the relative position between the alignment mark formed on the photomask and the alignment mark formed on the substrate. It is preferable to perform the fine alignment operation.

As another aspect of the present invention, a substrate cutting method is a method of cutting a substrate at a desired position.
Preparing a substrate on which an alignment mark made of a liquid crystal material is formed;
Adjusting the relative position between the substrate and the cutting means using the substrate position adjustment system described above;
And a step of cutting the substrate by a cutting means.

Moreover, the substrate bonding method as another aspect of the present invention is a method of bonding a pair of substrates at a desired relative position.
Forming an alignment mark made of a liquid crystal material on at least one of the pair of substrates;
Using the substrate position adjustment system according to any one of claims 1 to 5 to adjust the relative positions of the substrates;
And a step of adhering the substrates to each other.

  According to the substrate position adjusting system of the present invention, since the alignment mark made of a liquid crystal material is a latent image that can be detected only through the polarizing plate, even if the alignment mark is provided in the effective display area of the substrate, the display is performed. The relative position between the substrate and the photomask can be adjusted with high accuracy without disturbing the above.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The substrate position adjustment system according to the first aspect of the present invention will be described by taking as an example the production of a color filter incorporated in a liquid crystal display device or the like.

  FIG. 1 is a perspective view showing an outline of the system of the present invention used when performing RGB fine patterning of a color filter. A substrate 3 is placed on the XYθ stage 2 on the gantry 1, and an image sensor for detecting the alignment mark 4 formed on the substrate 3 is disposed on the alignment mark 4. Then, the system includes an imaging unit that optically images the alignment mark 4 formed on the substrate 3, an image optimization unit that optimizes the captured image, and alignment of the substrate based on the image information. And an alignment adjusting means for performing a fine adjustment operation. Hereinafter, each means will be described.

(1) Alignment mark imaging means The substrate used in the present invention is not particularly limited as long as it is a light-transmitting material, and an inorganic material such as glass or an organic material such as acrylic transparent resin can be suitably used. . Examples of the organic material include polyester resins, polycarbonate resins, polyarylate resins, polyether sulfone resins, acrylic resins, cellulose resins such as triacetyl cellulose, epoxy resins, cyclic olefin resins, and cyclic olefin copolymer resins.

  The substrate may be a plate or a film.

  On the substrate 3, a black matrix serving as a boundary of a colored region as a color filter is formed (not shown), and the region where the black matrix is formed becomes an effective display area of the color filter.

  In the present invention, the alignment mark 4 is formed in advance in this black matrix region. Since the alignment mark made of such a liquid crystal material becomes a latent image when it is not polarized as described below, even if an alignment mark is provided in the effective display area, display is not hindered.

  The alignment mark 4 can be formed by applying a coating liquid mainly composed of a nematic liquid crystal material on the substrate 3 having alignment ability. The coating film in which this nematic liquid crystal material is uniaxially oriented changes the polarization state of polarized light due to its refractive index anisotropy. As a result, when the alignment mark is observed while being sandwiched between parallel Nicol polarizing plates, the alignment mark can be observed as a dark display with respect to a bright background at a certain azimuth angle. That is, as shown in FIG. 2, since the light having a predetermined polarization direction that has passed through the first polarizing plate 6 is transmitted through the alignment mark 4 portion, the polarization direction changes. The transmitted light is absorbed by the second polarizing plate 7 having a parallel Nicol relationship with the first polarizing plate 6 and imaged as a dark display. For this reason, the alignment mark can be recognized only by taking an image through the polarizing plates 6 and 7, and the alignment mark cannot be recognized by normal non-polarized light, so that it becomes a latent image.

  As such a liquid crystal material, a nematic liquid crystal material fixed at a working temperature can be used. As an example, the liquid crystal structure can be fixed by quenching from the temperature showing the liquid crystal phase, a polymer liquid crystal material having a mesogenic group that exhibits liquid crystallinity in the side chain, and an unsaturated double molecule in the molecule. A polymerizable liquid crystal material having a bond and capable of fixing the liquid crystal structure by polymerization can be preferably used.

上記一般式（１）において、Ｒ^１及びＲ^２はそれぞれ水素又はメチル基を示すが、液晶相を示す温度範囲の広さからＲ^１及びＲ^２はともに水素であることが好ましい。Ｘは水素、塩素、臭素、ヨウ素、炭素数１〜４のアルキル基、メトキシ基、シアノ基、ニトロ基のいずれであっても差し支えないが、塩素又はメチル基であることが好ましい。また、上記一般式（１）において、分子鎖両端の（メタ）アクリロイロキシ基と芳香環とのスペーサーであるアルキレン基の鎖長を示すａ及びｂは、それぞれ個別に２〜１２の範囲で任意の整数をとり得るが、４〜１０の範囲であることが好ましく、６〜９の範囲であることがさらに好ましい。ａ＝ｂ＝０である一般式（１）の化合物は、安定性に乏しく、加水分解を受けやすい上に、化合物自体の結晶性が高い。また、ａ及びｂがそれぞれ１３以上である一般式（１）の化合物は、アイソトロピック転移温度（ＴＩ）が低い。この理由から、これらの化合物はどちらも液晶相を示す温度範囲が狭く好ましくない。 In the present invention, it is preferable to use a polymerizable liquid crystal material capable of fixing the liquid crystal structure as described below. Examples of such polymerizable nematic liquid crystal materials include compounds represented by the following general formula (1) and compounds represented by the following formulas (2-i) to (2-xi). it can. These compounds can be used alone or in combination.

In the above general formula (1), R ¹ and R ² each represent hydrogen or a methyl group, but both R ¹ and R ² are preferably hydrogen because of the wide temperature range showing the liquid crystal phase. X may be hydrogen, chlorine, bromine, iodine, an alkyl group having 1 to 4 carbon atoms, a methoxy group, a cyano group, or a nitro group, but is preferably a chlorine or methyl group. Moreover, in the said General formula (1), a and b which show the chain length of the alkylene group which is a spacer of the (meth) acryloyloxy group and aromatic ring of the molecular chain both ends are arbitrary in the range of 2-12, respectively. Although it can take an integer, it is preferably in the range of 4 to 10, and more preferably in the range of 6 to 9. The compound of the general formula (1) in which a = b = 0 is poor in stability, is susceptible to hydrolysis, and has high crystallinity. In addition, the compound of the general formula (1) in which a and b are each 13 or more has a low isotropic transition temperature (TI). For this reason, both of these compounds are not preferable because the temperature range in which the liquid crystal phase is exhibited is narrow.

In the above, an example of a polymerizable liquid crystal monomer has been described as a polymerizable liquid crystal material exhibiting nematic regularity. However, the present invention is not limited thereto, and a polymerizable liquid crystal oligomer, a polymerizable liquid crystal polymer, a polymer liquid crystal, etc. It is also possible to use. Such a polymerizable liquid crystal oligomer, a polymerizable liquid crystal polymer, and a polymer liquid crystal can be appropriately selected from those conventionally proposed.

  In the present invention, as described later, the position of the polarizing plate is such that high contrast imaging can be obtained by simultaneously rotating the two polarizing plates while maintaining the parallel Nicol state in which the background has the maximum luminance. Can be easily set, which is preferable in terms of speeding up the work.

  The liquid crystal material can be applied as it is on the substrate, but in order to match the viscosity with the coating device or to obtain a good alignment state, it is dissolved in an appropriate solvent such as an organic solvent to make an ink. Also good.

  Such a solvent is not particularly limited as long as it can dissolve the polymerizable nematic liquid crystal material as described above, but preferably does not erode the substrate. Specific examples include acetone, 3-methoxybutyl acetate, diglyme, cyclohexanone, tetrahydrofuran, toluene, xylene, chlorobenzene, methylene chloride, methyl ethyl ketone, and the like. The degree of dilution of the polymerizable liquid crystal material is not particularly limited, but it is 5 to 50%, more preferably 10 in view of the fact that the liquid crystal itself is a material with low solubility and high viscosity. It is preferable to dilute to about 30%.

  After applying a liquid crystal material on the substrate to form an alignment mark, in an alignment treatment step, the liquid crystal molecules in the liquid crystal are aligned by maintaining a predetermined temperature at which a uniaxial liquid crystal structure is developed. Next, the aligned liquid crystal molecules are cured to fix the liquid crystal structure.

  Here, in the curing treatment step, it is preferable to use a method in which liquid crystal molecules in the liquid crystalline material are photopolymerized and cured by irradiation with radiation. For example, after forming a semi-cured liquid crystal layer by evaporating the solvent in the coating film made of the liquid crystal material applied on the substrate using a method as described in JP-A-14-286935, It is preferable to irradiate the liquid crystal layer in an air atmosphere and cure the liquid crystal layer over time.

  The black matrix is used to prevent reflection of external light at the boundary between each pixel and increase the contrast of images and videos. Usually, it is a vertical and horizontal grid made up of black thin lines as viewed from the observation side. Or a pattern having an opening, such as a lattice shape in only one direction.

  In order to form a black matrix, first, the substrate 1 is sufficiently washed, and then a metal thin film is formed by various methods such as vapor deposition, ion plating, or sputtering using a metal such as chromium. In this case, a metal thin film made of chromium is most preferable in consideration of washing resistance and processing characteristics. In order to form the patterned black matrix as described above from the formed metal thin film, a normal photolithography method or the like can be used. For example, a photoresist is applied to the surface of the formed metal thin film. The film can be coated with a pattern mask and subjected to steps such as exposure, development, etching, and washing. The black matrix can also be formed by using an electroless plating method or a printing method using a black ink composition.

  The thickness of the black matrix is about 0.2 to 0.4 μm when it is formed as a thin film, and is about 0.5 to 2 μm when it is printed.

  In the present invention, the substrate on which the alignment mark as described above is formed is placed on the XYθ table, and the alignment mark is detected by the image sensor.

  In the substrate position adjusting system according to the first aspect of the present invention, as shown in FIG. 2, the substrate 3 is placed on the lower side (XYθ stage 2 side) so as to sandwich the substrate 3 between the two polarizing plates 6 and 7. ) And polarizing plates 6 and 7 are arranged on the upper side of the substrate 3 (on the image pickup element 5 side), respectively. The polarizing plate 7 on the lower side of the substrate 3 may be provided in the XYθ stage 2 as shown in FIG. 2, or a through hole or the like is provided in a part of the XYθ stage 2 so that light can pass therethrough. The polarizing plate 7 may be provided below the XYθ stage 2 or the polarizing plate 7 may be provided between the substrate 3 and the XYθ stage 2.

  On the other hand, the polarizing plate 6 provided on the image pickup device 5 side only needs to be disposed between the substrate 3 and the image pickup device 5, and may be one in which the image pickup device 5 and the polarizing plate 6 are integrated.

  As shown in FIG. 3, the two polarizing plates are provided so as to be rotatable in the θ direction (around the optical axis) so that the polarization direction can be changed in the XY directions. However, until the image optimization described later is performed, the two polarizing plates are arranged in a state other than crossed Nicols so that the substrate or the photomask can be observed. This is because if two polarizing plates are arranged in a crossed Nicol state, light is not transmitted and dark display is obtained, so that imaging contrast is deteriorated. In the present invention, it is preferable to arrange the two polarizing plates 6 and 7 in a parallel Nicol state so that the brightness of the image of the portion other than the alignment mark (background portion) is maximized.

  In the system according to the first aspect of the present invention, as shown in FIG. 2, light is incident on the substrate 3 by the projector 8 from the lower surface of the polarizing plate 7 provided on the lower side of the substrate, and the alignment mark on the substrate 3 is obtained. 4 is detected by imaging with the image sensor 5. The light from the projector 8 on the lower side of the substrate 3 passes through the polarizing plate 7 provided between the substrate 3 and the projector 8 and becomes linearly polarized light. This linearly polarized light changes its polarization state when light passes through the nematic liquid crystal that constitutes the alignment mark described above. Therefore, when the alignment mark is imaged in a parallel Nicol state, the alignment mark portion is displayed against a bright background. The captured image is displayed dark. Thus, since the alignment mark formed in the board | substrate can be recognized by an imaging means, the exact position of a board | substrate can be grasped | ascertained based on the image information from an image pick-up element.

  In the system according to the second aspect of the present invention, as shown in FIG. 4, a light source that irradiates light from the image sensor 5 side toward the surface of the substrate 3 and the substrate 3 opposite to the image sensor 5 side. It is comprised from the reflecting plate 10 provided in the side. A single polarizing plate 6 is provided between the image sensor 5 and the substrate 3. The reflecting plate 10 is not particularly limited as long as it can reflect light, and for example, a mirror, a material obtained by vapor-depositing aluminum or the like on a base material, or the like can be used.

  The light projected from the imaging element 5 side is first linearly polarized by the polarizing plate 6 and enters the substrate 3. At that time, the linearly polarized light transmitted through the place where the alignment mark 4 is formed in the substrate 3 changes its polarization state, and the light passing through the other place passes through the substrate 3 without changing its polarization state. . Next, the light transmitted through the substrate 3 is reflected by the reflecting plate 10 and passes through the substrate 3 again. At this time, the polarization state changes only for the light that passes through the place where the alignment mark 4 is formed, and the polarization state does not change for the light that passes through other places. The transmitted light passes through the polarizing plate 6 and enters the image sensor 5. Here, since the polarization state of the light transmitted through the alignment mark 4 is changed, a part of the light is absorbed by the polarizing plate 6. On the other hand, the light transmitted through the background is transmitted without being absorbed by the polarizing plate 6 because the polarization state has not changed. Therefore, in the captured image, the part with the alignment mark 4 is dark and the background part is bright. Thus, since the alignment mark 4 formed in the board | substrate 3 can be recognized by an imaging means, the exact position of a board | substrate can be grasped | ascertained based on the image information from an image pick-up element.

  In order to make light incident from the image sensor side, a projector may be provided separately from the image sensor, or a projector integrated with the image sensor may be used as shown in FIG.

  The light source light used in the present invention is not particularly limited as long as it can pass through an optical member other than the reflection plate installed on the optical path, but a monochromatic light or a light source having a narrow half-value width is preferable. The set phase difference of the alignment mark is preferably set to ½ wavelength of the light source used for observation by transmission and ¼ wavelength for observation by reflection. Parallel Nicol observation by combining monochromatic light or a light source with a narrow half-value width and a transmission observation alignment mark having a half-wave phase difference or a reflection observation alignment mark having a quarter-wave phase difference This is because in the system, the alignment mark is almost completely dark and high contrast can be secured.

  A CCD camera etc. can be used for an image pick-up element, for example. Further, an optical lens such as a zoom lens may be attached to the image sensor so that the alignment mark position can be accurately detected.

(2) Image optimization means An alignment mark made of a nematic liquid crystal material is not defined in the alignment direction of the liquid crystal relative to the substrate, that is, the orientation angle of the alignment axis. May be different. Therefore, depending on the alignment direction of the liquid crystal, an image with sufficient contrast may not be obtained, and it may be assumed that the substrate cannot be accurately aligned.

  The present invention includes means for optimizing an image obtained from the image sensor in order to solve the above-described problems. As shown in FIG. 3, based on the information from the image sensor, one of the two polarizing plates 6 and 7 is rotated around the optical axis (θ direction) to change the polarizing direction of the polarizing plate. Then, by stopping the polarizing plates 6 and 7 at a position where the contrast of the image is maximized, an image having the maximum contrast can be obtained with any alignment mark having any azimuth angle. Alignment becomes possible. In particular, in the substrate position adjustment system by transmission observation according to the first aspect of the present invention, more preferably, the two polarizing plates 6 and 7 are arranged so as to maintain a parallel Nicol state, and the contrast of the captured image is maximized. By rotating the two polarizing plates around the optical axis, the orientation in which the alignment mark is displayed darkest can be easily detected while maintaining a bright background image, so that the contrast of the image is maximized. In this state, the alignment mark can be imaged. It goes without saying that the brightness of the background can also be adjusted by adjusting the light source intensity from the projector or by rotating the two polarizing plates independently around the optical axis.

(3) Alignment adjusting means As described above, accurate position information of the substrate can be obtained by detecting the alignment mark.

  For example, in manufacturing a color filter, a color filter layer is formed by laminating RGB colors between pixels of a black matrix formed on a substrate. This color filter layer is formed, for example, by forming a red fine color filter region by photolithography, and repeating the same operation in order of green and blue to form a full color color filter layer.

  In the present invention, the alignment of the substrate and the photomask can be performed accurately by providing the alignment mark on the photomask used when forming the color filter layer together with the alignment of the substrate. For example, as shown in FIG. 5, the alignment mark 4 on the substrate 3 side is a cross mark (“+”), the alignment mark 12 on the photomask 11 side is a square mark (“□”), and the cross mark is inside the square mark. The substrate 3 and the photomask 11 can be aligned so that the Note that the alignment mark 12 provided on the photomask 11 side may be formed of a conventional metal thin film, or a nematic liquid crystal material used in the present invention.

  Such alignment adjustment means is performed by operating the XYθ stage on which the substrate is placed relative to the photomask based on the image obtained by the image optimization means. Specifically, with respect to the image data of the obtained alignment mark, the correction amount in the X-axis direction, the correction amount in the Y-axis direction, and the θ angle necessary for correct alignment are performed using image processing or the like. Each correction amount is calculated. This processing may be performed by a unit configured as a dedicated image processing apparatus, or may be performed by fetching image data into a PC and executing an image processing program.

  In addition, after the substrate is aligned with the calculated correction amounts of XYθ, the correction amount is calculated again by the imaging unit and the alignment adjustment unit, and it is verified whether the correction amount is within the standard range. Thus, more accurate alignment can be performed.

  Further, since the alignment between the substrate 3 and the photomask 11 is performed based on the relative position between them, only the stage 2 or the photomask 11 on which the substrate 3 is placed may be moved. The stage 2 and the photomask 11 may be moved. Both may be moved for position adjustment.

  The substrate position adjusting system according to the present invention can be suitably applied not only to substrate patterning when manufacturing the color filter substrate exemplified above, but also to those that need to adjust the relative position of the substrate. For example, the substrate cutting process can be applied to a cutting apparatus that uses the above-described substrate position adjustment system to perform a substrate cutting process at a coordinate position programmed in advance by a PC, using an alignment mark on the substrate as a base point.

  Also in the process of bonding the TFT substrate and the color filter substrate, an alignment mark made of nematic liquid crystal is formed on either or both substrates, and the relative position of both substrates is adjusted using the system. Thus, the bonding can be performed with high accuracy.

It is a perspective view of a substrate position adjustment system showing an embodiment of the present invention. It is a side view of a substrate position adjustment system showing an embodiment of the present invention. It is a perspective partial enlarged view of a substrate position adjustment system showing an embodiment of the present invention. It is a side view of the board | substrate position adjustment system which showed the other embodiment of this invention. It is an example which applied the board | substrate position adjustment system of this invention to photolithography.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stand 2 XY (theta) stage 3 Board | substrate 4,12 Alignment mark 5 Image pick-up element 6,7 Polarizing plate 8 Floodlight 10 Reflector 11 Photomask

Claims (15)

Imaging means for optically imaging the alignment mark formed on the substrate, image optimization means for optimizing the captured image, and alignment adjusting means for performing the fine alignment operation of the substrate based on the image information A substrate position adjustment system comprising:
The imaging means sandwiches a substrate between a pair of polarizing plates, projects light from one polarizing plate side, and images an alignment mark from the other polarizing plate side,
The image optimization means rotates at least one of the pair of polarizing plates around the optical axis so as to maximize the contrast of the captured alignment mark,
The alignment adjustment means performs fine adjustment of the position of the substrate based on the optimized image information,
A substrate position adjusting system, wherein the alignment mark is made of a liquid crystal material.   The substrate position adjusting system according to claim 1, wherein the pair of polarizing plates are arranged so as to be in a parallel Nicol state, and the pair of polarizing plates rotate around an optical axis while maintaining the parallel Nicol state. . Imaging means for optically imaging the alignment mark formed on the substrate, image optimization means for optimizing the captured image, and alignment adjusting means for performing the fine alignment operation of the substrate based on the image information A substrate position adjustment system comprising:
The imaging means projects light onto the substrate through the polarizing plate from the imaging position side, reflects light transmitted through the substrate by a light reflecting plate provided on the surface of the substrate opposite to the projection surface, and The upper alignment mark is imaged,
The image optimization means rotates the polarizing plate around the optical axis so as to maximize the contrast of the captured alignment mark,
The alignment adjustment means performs fine adjustment of the substrate position based on the optimized image information;
A substrate position adjusting system, wherein the alignment mark is made of a liquid crystal material.   The substrate alignment system according to claim 1, wherein the alignment mark is formed in an effective display area of the substrate.   The substrate position adjusting system according to any one of claims 1 to 4, wherein the liquid crystal material comprises a nematic liquid crystal material fixed in a uniaxial orientation.   Use of the substrate positioning system according to any one of claims 1 to 5 for photolithography.   Use according to claim 6, wherein the photolithography is performed in the patterning of a color filter.   Use of the substrate position adjusting system according to any one of claims 1 to 5 for substrate cutting.   Use of the substrate position adjusting system according to any one of claims 1 to 5 for substrate bonding processing. In the substrate position adjustment method, the alignment mark formed on the substrate is optically imaged, the captured image is optimized, and the alignment fine adjustment operation of the substrate is performed based on the optimized image information.
The imaging is performed by inserting a substrate between a pair of polarizing plates, projecting light from one polarizing plate side, and imaging an alignment mark from the other polarizing plate side,
Performing optimization of the image by rotating at least one of the pair of polarizing plates around the optical axis so that the contrast of the captured alignment mark is maximized,
A substrate position adjusting method, wherein the alignment mark is made of a liquid crystal material.   The substrate position adjusting method according to claim 10, wherein the pair of polarizing plates are arranged so as to be in a parallel Nicol state, and the pair of polarizing plates rotate around an optical axis while maintaining a parallel Nicol state. . In the substrate position adjustment method, the alignment mark formed on the substrate is optically imaged, the captured image is optimized, and the alignment fine adjustment operation of the substrate is performed based on the optimized image information.
The image is projected onto the substrate through the polarizing plate from the imaging position side, and the light transmitted through the substrate is reflected by the light reflecting plate provided on the surface of the substrate opposite to the light projecting surface. By imaging the alignment mark of
Performing the optimization of the image by rotating the polarizing plate around the optical axis so as to maximize the contrast of the captured alignment mark,
A substrate position adjusting method, wherein the alignment mark is made of a liquid crystal material.   A photomask is inserted between the substrate and the polarizing plate, and an alignment fine adjustment operation of the substrate is performed by a relative position between the alignment mark formed on the photomask and the alignment mark formed on the substrate. The substrate position adjusting method according to any one of 10 to 12. In a method of cutting a substrate at a desired position,
Preparing a substrate on which an alignment mark made of a liquid crystal material is formed;
Adjusting the relative position between the substrate and the cutting means using the substrate position adjusting system according to any one of claims 1 to 5;
Cutting the substrate with a cutting means. In a method of attaching a pair of substrates at a desired relative position,
Forming an alignment mark made of a liquid crystal material on at least one of the pair of substrates;
Using the substrate position adjustment system according to any one of claims 1 to 5 to adjust the relative positions of the substrates;
And a step of adhering the substrates together.

Images