JP4971835B2 - Exposure method and exposure apparatus - Google Patents

Description

  The present invention relates to a method of exposing a predetermined pattern by conveying an object to be exposed in one direction, irradiating exposure light from a light source to the object to be exposed at a predetermined timing through a photomask. The present invention relates to an exposure method and an exposure apparatus that detect the amount of misalignment and automatically correct the exposure light irradiation timing to improve the exposure position accuracy of the pattern.

A conventional exposure apparatus includes an exposure optical system that irradiates an exposure object with exposure light from a light source, and a conveying unit that is disposed to face the exposure optical system and carries the exposure object at a constant speed. And exposing an image of a mask pattern of a photomask interposed on the optical path of the exposure optical system on the object to be exposed. The exposure position of the exposure optical system in the moving direction of the object to be exposed is An imaging unit that images the reference pattern formed in advance on the object to be exposed, and a reference position preset in the reference pattern imaged by the imaging unit is detected, and the reference position is used as a reference. Control means for controlling the irradiation timing of the exposure light of the exposure optical system and exposing the image of the mask pattern of the photomask at a predetermined position of the object to be exposed (see, for example, Patent Document 1).
JP 2006-17895 A

  However, since such a conventional exposure apparatus does not have a function of automatically adjusting the exposure light irradiation timing, the mask pattern is set in a predetermined manner when the photomask arrangement is shifted in the conveyance direction of the object to be exposed. It was difficult to correctly expose the position. Therefore, it is difficult to ensure the exposure position accuracy of the pattern with high accuracy.

  In this case, in order to ensure the exposure position accuracy of the pattern with high accuracy, it is necessary to perform a plurality of trial exposures by changing the irradiation timing and find an appropriate irradiation timing.

  Accordingly, the present invention addresses such problems, and an exposure method and an exposure that attempt to automatically correct the exposure light irradiation timing by detecting the amount of misalignment of the photomask to improve the exposure position accuracy of the pattern. An object is to provide an apparatus.

In order to achieve the above object, an exposure method according to a first aspect of the present invention transports an object to be exposed having a reference pattern on its surface in one direction, and a predetermined timing from a light source to the object to be exposed via a photomask. Exposure method for exposing a plurality of mask patterns arranged in at least one line in a direction substantially orthogonal to the transport direction of the object to be exposed on the photomask, wherein the mask pattern array The center of the row of the mask pattern in the observation window provided in the photomask for observing the reference pattern at a position on the front side in the transport direction of the object to be exposed or outside the observation window axis are formed by matching the center axis on an axis parallel to the alignment mark configured to include the first and second fine-line pattern you intersect at different angles with respect to said axis, prior to A method of imaging by the imaging means arranged in a straight line a plurality of light receiving elements in the conveying direction in a direction substantially perpendicular to the object to be exposed, to process the image captured by the imaging means, said first and said alignment mark A step of measuring a distance between the second fine line patterns to calculate a shift amount of the photomask in the transport direction; and automatically correcting an exposure timing of the exposure light based on the shift amount of the photomask to And irradiating.

An exposure method according to a second aspect of the present invention conveys an object to be exposed having a reference pattern on its surface in one direction, irradiates the object to be exposed from a light source with a predetermined timing through a photomask, An exposure method for exposing a plurality of mask patterns arranged in at least one line on a photomask in a direction substantially orthogonal to the conveyance direction of the object to be exposed, the center of the mask pattern line on the photomask or A first fine line pattern formed on an axis parallel to the central axis and extending perpendicularly to the central axis or the axis and a second fine line pattern inclined at a predetermined angle. Imaging the alignment mark formed by an imaging unit in which a plurality of light receiving elements are aligned in a direction substantially orthogonal to the transport direction of the object to be exposed, and processing the image captured by the imaging unit Measuring a distance between the first and second fine line patterns of the alignment mark to calculate a shift amount of the photomask in the transport direction, and irradiating the exposure light according to the shift amount of the photomask. The step of automatically correcting the timing and irradiating the exposure light is executed .

Preferably , the imaging means captures a reference pattern provided on the object to be exposed and the alignment mark within the same field of view and simultaneously focuses and images .

More preferably , the step of irradiating the exposure light detects an edge located on the leading side in the transport direction of the reference pattern formed on the object to be exposed based on the image captured by the imaging unit, It is desirable to irradiate the exposure light at a timing when the object to be exposed is moved by a distance obtained by adding and correcting the deviation amount of the photomask to a preset value after the edge is detected.

More preferably , before the step of irradiating the exposure light, the image captured by the imaging means is processed, and an edge portion extending in parallel with the transport direction of the reference pattern provided on the object to be exposed Between the first and second fine line patterns of the alignment mark and a reference position preset on one of the fine line patterns so that the distance becomes a predetermined value. Further, it is desirable that the photomask is displaced in a direction substantially orthogonal to the transport direction relative to the object to be exposed .

In the second aspect of the invention, the photomask is provided with a viewing window on a side of the row of the mask pattern, which allows a reference pattern provided on the exposed object to be observed, and the alignment mark is placed on the viewing window. It is desirable that the inspection window is formed inside the window or outside the inspection window, and is disposed so as to face the object to be exposed so that the inspection window is on the front side in the transport direction of the object to be exposed .

Furthermore, in the first invention, the alignment mark includes a first fine line pattern extending perpendicular to an axis parallel to a central axis of the mask pattern row, and a predetermined angle with respect to the axis. It is desirable to include a second fine line pattern that is inclined at the angle.

In this case, or, in the second invention, the alignment mark, two of the first thin line-shaped pattern, and one of said provided between the first thin line-shaped pattern of the two It is desirable to include the second fine line pattern .

According to a third aspect of the present invention, there is provided an exposure apparatus according to a third aspect of the present invention, comprising: a conveying unit that conveys an object to be exposed having a reference pattern on its surface in one direction; A pattern, a viewing window for observing the reference pattern of the object to be exposed, and a central axis of the mask pattern array in or outside the viewing window. is formed by matching the center axis on an axis parallel to, a photomask provided with the alignment marks configured to include the first and second fine-line pattern that intersect at different angles with respect to said axis, the object to be exposed as the viewing window with the central axis of the column of the mask pattern is substantially perpendicular to the conveying direction of the object to be exposed is the transport direction front side of the object to be exposed for the columns of the mask pattern A mask stage for holding in proximity face with a light source that emits the exposure light irradiated to the object to be exposed through the photomask, side by side plurality Kazunao lines the in the conveying direction and a direction substantially orthogonal to the object to be exposed An image pickup means for picking up the alignment mark of the photomask, processing an image picked up by the image pickup means, and setting an interval between the first and second fine line patterns of the alignment mark. Control means for measuring and calculating a shift amount of the photomask in the transport direction, and correcting and controlling the exposure light irradiation timing by the shift amount of the photomask.

Furthermore, an exposure apparatus according to a fourth aspect of the present invention includes a transport unit that transports an object having a reference pattern provided on the surface in one direction, and a plurality of masks arranged above the transport unit and arranged in at least one row. A pattern and a first thin line pattern formed on a central axis of the row of the mask pattern or on an axis parallel to the central axis and extending perpendicular to the central axis or the axis at a predetermined angle A photomask provided with an alignment mark including an inclined second fine line pattern is exposed so that the central axis of the row of the mask pattern is substantially orthogonal to the transport direction of the object to be exposed A mask stage that is held in close proximity to the body, a light source that emits exposure light that irradiates the object to be exposed through the photomask, and a line that is aligned in a direction substantially perpendicular to the transport direction of the object to be exposed. An image pickup means for picking up the alignment mark of the photomask, processing an image picked up by the image pickup means, and setting an interval between the first and second fine line patterns of the alignment mark. Control means for measuring and calculating a shift amount of the photomask in the transport direction and correcting and controlling the exposure light irradiation timing by the shift amount of the photomask .

Preferably , the imaging means captures a reference pattern provided on the object to be exposed and the alignment mark within the same field of view and simultaneously focuses and images .

More preferably , the control means detects an edge located on the leading side in the transport direction of the reference pattern formed on the object to be exposed based on an image picked up by the image pickup means, and the edge is It is desirable to control so that the exposure light is irradiated at a timing when the object to be exposed moves by a distance obtained by adding and correcting the deviation amount of the photomask to a preset value after detection .

More preferably , the mask stage is formed so that the photomask can be displaced in a direction substantially orthogonal to a conveyance direction of the object to be exposed, and the control unit includes the reference pattern and the alignment imaged by the imaging unit. Based on the image of the mark , the edge of the reference pattern extending in parallel with the transport direction and the first and second fine line patterns of the alignment mark are preliminarily placed on one of the fine line patterns. It is desirable to calculate a distance from the set reference position, and to drive and control the mask stage so that the distance becomes a predetermined value, thereby displacing the photomask in a direction intersecting the transport direction .

The light source is preferably a flash lamp that is controlled by the control means to be turned on and off .

According to the first, second, ninth, or tenth aspect of the present invention, it is possible to detect the displacement amount of the photomask and automatically correct the exposure light irradiation timing, thereby improving the exposure position accuracy of the mask pattern. Therefore, it is not necessary to perform a plurality of trial exposures before performing the main exposure to find an appropriate timing of the exposure light, and the exposure process time can be shortened.

According to the invention of claim 3 or 11 , the imaging means captures the reference pattern of the object to be exposed and the alignment mark provided on the photomask within the same field of view, and simultaneously focuses and images the exposure light. The calculation of the irradiation timing and the amount of deviation in the direction substantially perpendicular to the conveyance direction between the reference pattern of the object to be exposed and the mask pattern of the photomask can be performed in real time. Therefore, exposure can be performed by increasing the conveyance speed of the object to be exposed, and the exposure time can be further shortened.

Further, according to the invention according to claim 4 or 12 , since the reference of the exposure light irradiation timing is set to the edge located on the leading side in the transport direction of the reference pattern formed on the exposed object, the imaging unit having side by side elements Kazunao line in a direction substantially perpendicular to the conveying direction of the object to be exposed, it is possible to easily detect the edges by detecting the brightness change. Therefore, detection of the shift amount of the photomask and detection of the edge portion of the reference pattern of the object to be exposed can be performed by a single imaging unit, and the configuration of the imaging unit can be simplified.

And according to the invention concerning Claim 5 or 13 , it can align with the mask pattern of a photomask, and the reference | standard pattern of a to-be-exposed body, and can improve the exposure position accuracy of a mask pattern more.

According to the invention of claim 6 , a viewing window is formed on the side of the mask pattern row, and the reference pattern provided on the object to be exposed is conveyed through the viewing window so as to face the photomask. Since the observation is performed, it becomes easy to capture the reference pattern by the imaging means.

According to the seventh aspect of the present invention, the amount of displacement of the photomask in the transport direction of the object to be exposed is determined by measuring the interval between the first and second fine line patterns and storing the interval in advance in the memory. It can be calculated by calculating the difference from the stored reference value. In addition, the detection resolution of the photomask shift amount can be improved. Therefore, the control accuracy of the exposure light irradiation timing can be improved.

Furthermore, according to the invention according to claim 8 , the amount of displacement of the photomask in the conveyance direction of the object to be exposed is obtained by measuring the interval between adjacent thin line patterns and calculating the difference between the intervals. Can be calculated. Therefore, it is not necessary to store the reference value in the memory in advance. In addition, the detection resolution of the photomask shift amount can be improved. Therefore, the control accuracy of the exposure light irradiation timing can be improved.

According to the fourteenth aspect of the present invention , exposure light irradiation and stop control can be easily performed, and the control can be performed at high speed.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a schematic view showing a first embodiment of an exposure apparatus according to the present invention. This exposure apparatus conveys an object to be exposed in one direction, irradiates the object to be exposed with exposure light at a predetermined timing through a photomask 9, and exposes a predetermined pattern. The stage 2, the light source 3, the imaging unit 4, the illumination unit 5, and the control unit 6 are included. In the following description, the case where the object to be exposed is composed of a color filter substrate 7 coated with a color resist as a photosensitive resin will be described.

  The transport means 1 is configured to place the color filter substrate 7 on the upper surface of the stage 8 as a placement surface and transport it in the direction of arrow A. A transport motor (not shown) is controlled by the control means 6 described later. The stage 8 is moved. Further, the transport means 1 is provided with a position detection sensor and a speed sensor (not shown) such as an encoder and a linear sensor, and the output is fed back to the control means 6 to enable position detection and speed control. Yes. The stage 8 is provided with an opening (not shown) corresponding to the entire exposure area of the color filter substrate 7, and the color filter substrate 7 is provided by the illumination means 5 described below disposed below the stage 8. Can be illuminated from below.

  A mask stage 2 is provided above the transport means 1. The mask stage 2 holds a photomask 9 (see FIG. 2) provided with a plurality of mask patterns 12 in close proximity to the color filter substrate 7 with a gap of, for example, 100 to 300 μm. An opening is provided corresponding to the area where the plurality of mask patterns 12 are formed, and the peripheral edge of the photomask 9 is held. The mask stage 2 is controlled by the control means 6 so that the photomask 9 can be displaced in a direction substantially orthogonal to the transport direction of the color filter substrate 7 (the direction of arrow A in FIG. 1). In this case, the means for driving the mask stage 2 can be configured by combining, for example, a motor, a ball screw, and a guide rail. The description of being substantially orthogonal means that it is orthogonal within a predetermined allowable range, and so on.

  Here, as shown in FIG. 2, the photomask 9 includes a transparent substrate 10, a light shielding film 11, a mask pattern 12, an alignment mark 13, and a viewing window 14.

  The transparent substrate 10 is a transparent glass substrate that transmits ultraviolet light and visible light with high efficiency, and is made of, for example, quartz glass. As shown in FIG. 3 or 4, a light shielding film 11 is formed on one surface 10 a of the transparent substrate 10. The light shielding film 11 shields exposure light and is formed of an opaque thin film of, for example, chromium (Cr).

As shown in FIG. 2, for example, a plurality of mask patterns 12 are formed in the light shielding film 11 in a line. The plurality of mask patterns 12 are openings having a predetermined shape that can irradiate exposure light to the color filter substrate 7 that is transported oppositely, and are formed of the black matrix 15 formed on the color filter substrate 7 shown in FIG. It is transferred onto the pixel 16 (reference pattern). Further, for example, the pixel 16 has a rectangular shape that substantially matches the vertical and horizontal widths, and is formed at an interval that matches the pitch interval of the pixels 16. Then, as shown in FIG. 2, for example, the lower edge in the drawing of the mask pattern 12a positioned near the center portion is previously set as the reference position S _1. 2 shows a case where a plurality of mask patterns 12 are provided in a line, the mask patterns 12 may be a plurality of lines.

  As shown in FIG. 3, an ultraviolet antireflection film 17 is formed in a region (see FIG. 2) corresponding to the region where the mask pattern 12 is formed on the other surface 10b of the transparent substrate 10, and exposure is performed. The transmission efficiency of the ultraviolet component contained in the light can be improved.

As shown in FIG. 2, an alignment mark is formed on the side of the row of mask patterns 12 by aligning the central axis on an axis Y parallel to the central axis X of the mask pattern 12 and separated by a predetermined distance L. 13 is provided. The alignment mark 13 aligns a reference position S ₁ preset on the mask pattern 12 with a reference position S ₂ preset on the pixel 16 of the color filter substrate 7 (see FIG. 5). This is for detecting the amount of displacement of the arrangement of the photomask 9 and is composed of at least two thin line patterns intersecting the axis Y at different angles. A specific configuration example thereof includes two fine line patterns 18a as first fine line patterns extending perpendicularly to an axis Y parallel to the central axis X of the row of mask patterns 12 as shown in FIG. , 18b and a fine line pattern 18c as a second fine line pattern provided between the two fine line patterns 18 and inclined at an angle of 45 degrees with respect to the axis Y. Of the two fine line patterns 18a and 18b extending perpendicular to the axis Y parallel to the center axis X of the row of the mask pattern 12, for example, the alignment reference is placed on the lower fine line pattern 18a in FIG. The position is preset. Thus, by adjusting the distance the position of the photomask 9 to a predetermined value between the reference position S ₂ of the thin line-shaped pattern 18a and the color filter substrate 7, the reference position S of the mask pattern 12 can ₁ and positioning of the reference position S ₂ of the color filter substrate 7. The inclination angle of the fine line pattern 18c is not limited to 45 degrees. The alignment mark 13 includes two fine line patterns 18a and 18b orthogonal to the axis Y, and a fine line pattern 18c provided between the two fine line patterns 18a and 18b and inclined with respect to the axis Y. It is not restricted to what was comprised, What kind of thing may be sufficient as long as it comprised including the fine linear pattern orthogonal to the axis | shaft Y, and the inclined fine linear pattern. However, in the following description, the case where the alignment mark 13 is constituted by the three thin line patterns 18a to 18c will be described.

As shown in FIG. 2, a viewing window 14 is formed on the side of the row of the mask pattern 12. The viewing window 14 is for observing the pixels 16 formed on the color filter substrate 7 shown in FIG. 5 that are transported oppositely. The imaging means 4 described later uses, for example, the vicinity of the center as shown in FIG. It has become possible to detect the reference position S ₂ which is preset in the lower edge in the figure extending parallel to the conveying direction of the pixels 16a located part. Then, as shown in FIG. 2, it is formed in a rectangular shape extending from one end 9a side to the other end 9b side in parallel with the central axis X of the row of the mask pattern 12, and inside thereof. The alignment mark 13 is provided. The viewing window 14 is formed in a rectangular shape extending from the central portion toward the one end portion 9a in parallel with the central axis X of the row of the mask pattern 12, and the alignment mark 13 is disposed outside thereof. May be.

  In addition, as shown in FIG. 4, visible light is transmitted through an area (see FIG. 2) corresponding to the formation area of the viewing window 14 and the alignment mark 13 on the other surface 10 b of the transparent substrate 10. A reflective wavelength selective film 19 is formed, and an ultraviolet component contained in the exposure light is irradiated to the color filter substrate 7 through the observation window 14 and the alignment mark 13 formation region, and the color resist applied to the color filter substrate 7 is exposed. Can be prevented.

  As shown in FIG. 1, the photomask 9 has the light-shielding film 11 formed side down, the viewing window 14 is positioned on the front side of the color filter substrate 7 in the transport direction, and the mask pattern 12 array. Is held on the mask stage 2 so that the central axis X of the center is substantially perpendicular to the transport direction (arrow A direction).

  A light source 3 is provided above the mask stage 2. The light source 3 emits ultraviolet exposure light that irradiates the color filter substrate 7 via the photomask 9 and is a flash lamp that is turned on and off under the control of the control means 6. The exposure light emitted from the light source 3 is collimated by, for example, the condenser lens 20 and irradiates the photomask 9.

An imaging unit 4 is provided above the stage 8 of the transport unit 1. The imaging means 4 captures and captures the pixels 16 of the black matrix 15 formed on the color filter substrate 7 and the alignment marks 13 formed on the photomask 9 in the same field of view through the half mirror 21. There is a side-by-side line camera having a plurality of light receiving elements 22 (see FIG. 9) to Kazunao line in a direction substantially perpendicular to the conveying direction of the color filter substrate 7. As shown in FIG. 1, the specific configuration example is formed on a plurality of light receiving elements 22 and pixels 16 or a photomask 9 of a black matrix 15 disposed in front of the light receiving elements 22 and formed on the color filter substrate 7. A condenser lens 23 that forms an image of the alignment mark 13 on the light receiving surface of the light receiving element 22, and an optical distance correction unit 24 provided between the light receiving element 22 and the condenser lens 23 are provided.

  As shown in FIG. 6, the optical distance correction unit 24 substantially matches the optical distance between the light receiving element 22 and the color filter substrate 7 and the optical distance between the light receiving element 22 and the photomask 9. And a transparent member having a predetermined refractive index larger than that of air, for example, a glass plate. As a result, the pixels 16 of the color filter substrate 7 and the alignment marks 13 of the photomask 9 that are shifted in the optical axis direction of the image pickup means 4 can be simultaneously focused and imaged.

  An illumination unit 5 is provided below the stage 8 of the transport unit 1 so as to face the mask stage 2. The illumination means 5 emits illumination light composed of visible light to illuminate the color filter substrate 7 from the back surface, and the imaging means 4 can image the pixels 16 of the color filter substrate 7 and the alignment marks 13 of the photomask 9. For example, a halogen lamp or the like. An ultraviolet cut filter (not shown) is provided in front of the illumination unit 5 in the radiation direction of the illumination light, and the color resist on the color filter substrate 7 is exposed by ultraviolet rays contained in visible light emitted from the illumination unit 5. Is prevented.

A control means 6 is provided in electrical connection with the transport means 1, imaging means 4, mask stage 2, and light source 3. The control means 6 processes the image picked up by the image pickup means 4, measures the intervals between the three fine line patterns 18 a to 18 c constituting the alignment mark 13 of the photomask 9, and the color filter substrate of the photomask 9. 7 is calculated, and the exposure light irradiation timing is corrected and controlled by the amount of deviation of the photomask 9, and as shown in FIG. 26, a mask stage drive controller 27, a light source drive controller 28, an illumination means drive controller 29, a calculation unit 30, a memory 31, and a control unit 32.

  The transfer means drive controller 25 moves the stage 8 of the transfer means 1 in the direction of arrow A at a predetermined speed, and feeds back the output of the speed sensor provided in the transfer means 1 to control the speed. Yes.

  The image processing unit 26 binarizes the image picked up by the image pickup means 4 and sequentially outputs image data for one line.

Furthermore, the mask stage drive controller 27, the distance between the alignment reference position of the alignment mark 13 of the reference position S ₂ and the photomask 9 pixels 16 of the color filter substrate 7 (fine linear pattern 18a) becomes a predetermined value Thus, the mask stage 2 is displaced.

  Furthermore, the light source drive controller 28 controls the turning on and off of the light source 3. The lighting means drive controller 29 controls the lighting means 5 to be turned on and off.

  The arithmetic unit 30 also includes two adjacent thin line patterns 18a, 18a to 18c of the three thin line patterns 18a to 18c of the alignment mark 13 provided on the photomask 9 based on the image data from the image processing unit 26. The distances 18c, 18b, and 18c are measured and the difference is calculated to calculate the amount of deviation in the transport direction of the photomask 9, and the second is positioned in the transport direction of the pixels 16 formed on the color filter substrate 7. The position data of the two edges 16b and 16c are input from the position sensor of the transport means 1, the center position between the two edges 16b and 16c is calculated, and the mask pattern is detected after the center position of the pixel 16 is detected. The shift amount of the photomask 9 is added to the distance L between the center axis X of the 12 columns and the center axis Y of the alignment mark 13.

Further, the memory 31 stores control parameters input by operating means (not shown), such as the conveyance speed V of the color filter substrate 7, the irradiation time of the light source 3, the output value of the light source 3, and the center of the mask pattern 12 column. set distance D between the distance L, the reference position of the reference position S ₂ and the alignment marks 13 of the pixels 16 of the color filter substrate 7 between the center axis Y of the axis X and the alignment mark 13 (fine linear pattern 18a), And the result etc. which were calculated by the said calculating part 30 are preserve | saved temporarily.
And the said control part 32 integrates and controls the whole apparatus so that each said component may drive appropriately.

Next, the operation of the exposure apparatus configured as described above and the exposure method performed using the exposure apparatus will be described.
First, the side on which the photomask 9 forms the light shielding film 11 is face down, the viewing window 14 is positioned on the front side of the color filter substrate 7 in the transport direction (arrow A direction), and the central axis X of the row of the mask pattern 12 is It is held on the mask stage 2 so as to be substantially orthogonal to the transport direction.

  Next, the color filter substrate 7 coated with a predetermined color resist is placed at a predetermined position on the stage 8 of the transport means 1. When an exposure start switch (not shown) is turned on, the exposure apparatus is activated and the illumination unit 5 is turned on by the illumination unit drive controller 29 of the control unit 6. Further, the conveyance means drive controller 25 is activated and the stage 8 starts moving in the direction of arrow A shown in FIG. 1 at a predetermined speed V, and the color filter substrate 7 is conveyed in the same direction. Further, the imaging unit 4 is activated, and the image on the color filter substrate 7 and the alignment mark 13 of the photomask 9 are simultaneously focused through the viewing window 14 of the photomask 9 and captured by the image processing unit 26 of the control unit 6. The binarization process is performed, and image data for one line is sequentially output.

Here, in the calculation part 30 of the control means 6, first, based on the image data of the image imaged by the imaging means 4, as shown in FIG. 8, the three thin linear patterns of the alignment mark 13 of the photomask 9 are shown. The distances G ₁ and G ₂ between two adjacent fine line patterns 18a and 18c and 18b and 18c among 18a to 18c are measured. Specifically, after detecting the edges of the three fine line patterns 18a to 18c based on the luminance change of the image picked up by the image pickup means 4, the center position of each fine line pattern is detected. Then, the difference between the gaps G ₁ and G ₂ between the two adjacent thin line patterns 18a, 18c and 18b, 18c is calculated, and the shift amount G = (G ₁ −G ₂ ) / 2 in the transport direction of the photomask 9 is calculated. Is calculated. This deviation amount G is temporarily stored in the memory 31.

Next, the leading edge portion of the two edge portions 16b and 16c positioned in the transport direction of the pixel 16 of the color filter substrate 7 shown in FIG. 16b is detected. The detection of the leading edge 16b in the transport direction of the pixel 16 can be detected by capturing the moment when the image of the imaging means 4 changes from dark to bright. When the conveyance direction leading side edge 16b of the pixel 16 is detected, the position data P ₁ is obtained by the output of the position sensor of the transport means 1.

Further, it captures the moment when image pickup means 4 changes from bright to dark, the conveying direction trailing side edge portion 16c of the pixel 16 shown in FIG. 9 is detected, the position data P ₂ is the position of the transport means 1 Acquired by the output of the sensor.

Next, by using the two position data P ₁ and P ₂ , the central position P ₀ between the two edges 16 b and 16 c of the pixel 16 is calculated by the calculation unit 30 as (P ₁ + P ₂ ) / 2. Is calculated by In the arithmetic unit 30, the distance L between the center position P _{0 of the} pixel 16, the center axis X of the row of the mask pattern 12 and the center axis Y of the alignment mark 13, and the shift amount in the transport direction of the photomask 9. Based on G, the irradiation position P of the exposure light is
P = Ks × P ₀ + L + Ke × G (1)
Is obtained by calculating. The calculation result is temporarily stored in the memory 31. In Equation (1), Ks and Ke are resolutions of the image pickup means 4, Ks is the resolution in the transport direction of the color filter substrate 7, and Ke is the resolution between adjacent light receiving elements 22 of the image pickup means 4. ing.

At the same time, based on the luminance change of the image picked up by the image pickup means 4, the reference position S ₂ shown in FIG. 9 set in advance on the pixel 16 of the color filter substrate 7 and the reference position set in advance on the alignment mark 13 ( distance _{D 1} of the between the thin line pattern 18a) is measured by the arithmetic unit 30.

Then, in the mask stage drive controller 27, a distance D ₁ that is the measurement is compared with a predetermined value D read out from the memory 31, as shown in FIG. _{10 (D-D 1) =} 0 and becomes as a mask The stage 2 is displaced by the mask stage drive controller 27 in a direction crossing the transport direction. As shown in FIG. 9, when the photomask 9 is displaced in the arrow B direction relative to the color filter substrate 7, the photomask 9 may be moved in the arrow C direction as shown in FIG. .

  Subsequently, the color filter substrate 7 is conveyed in the direction of arrow A shown in FIG. At this time, in the light source drive controller 28, while the color filter substrate 7 is being transported, the position data of the color filter substrate 7 that is always output from the position sensor of the transport unit 1 and the exposure light irradiation position read from the memory 31. P data is compared. When the two data coincide with each other, a trigger for turning on the light source 3 is output from the light source drive controller 28 to the light source 3, and the light source 3 is turned on for a predetermined time. As a result, exposure light is emitted from the light source 3 for a predetermined time, and the mask pattern 12 of the photomask 9 is exposed onto the pixels 16 of the color filter substrate 7.

Thereafter, each time the center position P ₀ of each pixel 16 aligned along the transport direction of the color filter substrate 7 is detected, the exposure light irradiation position P is calculated by calculating the above equation (1). Then, each time the color filter substrate 7 is transported and reaches the exposure light irradiation position P, a trigger for turning on the light source 3 is output from the light source drive controller 28 to the light source 3, and the light source 3 is turned on for a predetermined time. Thereby, the mask pattern 12 of the photomask 9 is exposed on each pixel 16 of the color filter substrate 7.

  In this case, if every two triggers for driving the light source 3 to be output are output, as shown by hatching in FIG. 5, two rows are arranged for the plurality of pixels 16 of the color filter substrate 7. Can be exposed.

In the first embodiment, the case where the exposure timing is set based on the detection of the center position P ₀ of the pixel 16 of the color filter substrate 7 has been described. However, the present invention is not limited to this, and the pixel 16 The exposure timing may be set based on the detection of the leading edge 16b in the transport direction.

  FIG. 12 is a front view showing the schematic arrangement of the second embodiment of the exposure apparatus of the present invention. The difference from the first embodiment is that, as shown in FIG. 13, an alignment mark 13 is provided on the central axis of a plurality of mask pattern columns provided in a line on the photomask 9, for example. Therefore, in the second embodiment, the imaging unit 4 images the alignment mark 13 of the photomask 9 and the pixel 16 of the color filter substrate 7 observed through the mask pattern 12 simultaneously.

  According to the exposure apparatus of the second embodiment configured as described above, first, the alignment mark 13 is imaged by the imaging means 4, and the shift amount G of the photomask 9 in the arrow A direction as shown in FIG. Is calculated. Next, when the image pickup means 4 detects the leading edge in the transport direction of the pixels 16 of the color filter substrate 7 through the mask pattern 12 of the photomask 9, the exposure light irradiation timing is calculated. For example, if the width of the pixel 16 in the transport direction is W, the leading edge of the pixel 16 in the transport direction is detected, and the exposure light is emitted when the color filter substrate 7 moves by (W / 2 + G). An irradiation timing is set, and at the same time, the light source 3 is turned on for a predetermined time and irradiated with exposure light. Here, the resolutions Ks and Ke of the imaging unit 4 are not considered, but in order to further improve the exposure position accuracy, the exposure light irradiation timing may be calculated in consideration of the resolution.

At the same time, through a mask pattern 12 of the photomask 9 by the imaging unit 4, the reference position S _2, which is set to the pixel 16 of the color filter substrate 7 is detected, as in the first embodiment, the reference position S ₂ And the distance between the alignment mark 13 and the fine line pattern 18a is measured. Then, the photomask 9 is displaced in a direction substantially orthogonal to the transport direction of the color filter substrate 7 so that this distance matches a preset value. Thus, the reference position S ₂ of the pixels 16 of the reference position S ₁ and the color filter substrate 7 set in the mask pattern 12 of the photomask 9 is aligned.

In the above first and second embodiments, a case has been described in which to align the reference position S ₂ of the reference position S ₁ and the color filter substrate 7 of the photomask 9, for example, a mask of a photomask 9 When the shape of the pattern 12 is a line shape having a length corresponding to the length of a row of pixels 16 aligned in a direction substantially orthogonal to the conveyance direction of the color filter substrate 7, the photomask 9 and the color filter substrate 9 It is not necessary to take the alignment.

  In the first and second embodiments, the case where exposure light irradiation and stop control is performed by turning on and off the light source has been described. However, the present invention is not limited to this, and by opening and closing the shutter. You may control exposure light irradiation and a stop.

  Further, in the first and second embodiments, the case where the illumination unit 5 is provided below the stage 8 of the transport unit 1 and the backlight is used is described. However, the present invention is not limited to this, and the stage 8 is not limited thereto. It is good also as an epi-illumination by providing above.

In the above description, the case of observing the pixels 16 of the color filter substrate 7 through the viewing window 14 or the mask pattern 12 of the photomask 9 has been described. However, the present invention is not limited to this. Imaging means for detecting the displacement amount G of the arrangement of the photomask 9 may be provided, and other imaging means for imaging the pixels 16 of the color filter substrate 7 may be provided on the front side in the transport direction of the photomask 7. In this case, the timing for executing the exposure from the detection of the center position P ₀ of the conveying direction leading side edge 16b or pixels 16 of the pixel 16 by the other imaging means, the deviation amount G of the arrangement of the photomask 9 What is necessary is just to correct.

  Further, in the above description, the case where the exposure light is intermittently irradiated at a predetermined timing has been described. However, the present invention is not limited to this, and the exposure light irradiation timing at the start of the exposure is misaligned. You may correct | amend with the quantity G.

  In the above description, the case where the object to be exposed is the color filter substrate 7 has been described. However, the present invention is not limited to this, and the object to be exposed is provided with a predetermined reference pattern in a matrix. Anything may be used.

1 is a schematic diagram showing a first embodiment of an exposure apparatus according to the present invention. It is a top view of the photomask used in the said exposure apparatus. It is XX sectional drawing of the said photomask. It is the YY sectional view taken on the line of the said photomask. It is a top view of the color filter board | substrate used in the said exposure apparatus. It is explanatory drawing which shows optical distance correction | amendment of the imaging means with which the said exposure apparatus was equipped. It is a block diagram which shows schematic structure of the control means of the said exposure apparatus. It is explanatory drawing which shows the calculation principle of the deviation | shift amount of the said photomask arrangement | positioning. It is a figure explaining the alignment adjustment of the said photomask and a color filter substrate, and is a top view which shows the state before adjustment. It is a figure explaining the alignment adjustment of the said photomask and a color filter substrate, and is a top view which shows the state after adjustment. It is a top view explaining the irradiation timing of the exposure light in the said exposure apparatus. It is a front view which shows schematic structure of 2nd Embodiment of the exposure apparatus by this invention. It is a top view which shows one structural example of the photomask applied to the exposure apparatus of the said 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Conveyance means 2 ... Mask stage 3 ... Light source 4 ... Imaging means 6 ... Control means 7 ... Color filter substrate (exposed body)
9 ... Photomask 12 ... Mask pattern 14 ... Viewing window 16 ... Pixel (reference pattern)
18a, 18b ... fine line pattern (first fine line pattern)
18c ... fine line pattern (second fine line pattern)

Claims (14)

An object to be exposed having a reference pattern provided on the surface is conveyed in one direction, exposure light is irradiated from a light source to the object to be exposed through a photomask at a predetermined timing, and the object to be exposed is exposed on the photomask. An exposure method for exposing a plurality of mask patterns arranged in at least one line in a direction substantially orthogonal to a transport direction,
In order to observe the reference pattern at a position on the front side in the transport direction of the object to be exposed with respect to the row of mask patterns, the mask is provided inside or outside the viewing window provided in the photomask. It is formed by matching the center axis on an axis parallel to the central axis of the column of the pattern, the alignment mark configured to include the first and second fine-line pattern you intersect at different angles relative to the axis the steps of imaging by the imaging means said aligned in a straight line a plurality of light receiving elements in the conveying direction and a direction substantially orthogonal to the object to be exposed,
Processing an image picked up by the image pickup means, measuring an interval between the first and second fine line patterns of the alignment mark, and calculating a shift amount of the photomask in the transport direction;
Irradiating the exposure light by automatically correcting the irradiation timing of the exposure light according to the shift amount of the photomask; and
The exposure method characterized by performing. An object to be exposed having a reference pattern provided on the surface is conveyed in one direction, exposure light is irradiated from a light source to the object to be exposed through a photomask at a predetermined timing, and the object to be exposed on the photomask An exposure method for exposing a plurality of mask patterns arranged in at least one line in a direction substantially orthogonal to a transport direction,
Formed on a central axis of a mask pattern row of the photomask or on an axis parallel to the central axis, and at a predetermined angle with the first thin linear pattern extending perpendicular to the central axis or the axis Imaging an alignment mark including the inclined second fine line pattern by an imaging means in which a plurality of light receiving elements are aligned in a direction substantially orthogonal to the conveying direction of the object to be exposed;
Processing an image picked up by the image pickup means, measuring an interval between the first and second fine line patterns of the alignment mark, and calculating a shift amount of the photomask in the transport direction;
Irradiating the exposure light by automatically correcting the irradiation timing of the exposure light according to the shift amount of the photomask; and
The exposure method characterized by performing. 3. The exposure method according to claim 1 , wherein the imaging unit captures a reference pattern provided on the object to be exposed and the alignment mark within the same field of view and simultaneously focuses the images. The step of irradiating the exposure light detects, based on the image picked up by the image pickup means, an edge located on the leading side in the transport direction of the reference pattern formed on the object to be exposed, and the edge is 3. The exposure according to claim 1 , wherein the exposure light is irradiated at a timing when the object to be exposed is moved by a distance obtained by adding and correcting a deviation amount of the photomask to a preset value after detection. Method. Before the step of irradiating the exposure light, the image picked up by the image pickup means is processed, and an edge portion of the reference pattern provided on the object to be exposed and extending in parallel with the transport direction and the alignment mark The photomask is configured such that a distance from a preset reference position on either one of the first and second fine line patterns is calculated and the distance becomes a predetermined value. The exposure method according to claim 1, wherein the position is displaced in a direction substantially orthogonal to the transport direction relative to the object to be exposed. The photomask is provided with a viewing window on a side of the row of the mask pattern that enables observation of a reference pattern provided on the object to be exposed, and the alignment mark is formed inside or outside the viewing window. 3. The exposure method according to claim 2 , wherein the viewing window is disposed to face the object to be exposed so that the observation window is on the front side in the transport direction of the object to be exposed. The alignment mark includes a first fine line pattern extending perpendicular to an axis parallel to a central axis of the mask pattern row, and a second fine line pattern inclined at a predetermined angle with respect to the axis. the exposure method according to claim 1, characterized in that it is configured to include and. The alignment marks are two of the first fine line pattern, and that the one of the second fine-line pattern which is provided between the first thin line-shaped pattern of the two constituted by containing 8. The exposure method according to claim 2 or 7 , wherein: A transport means for transporting an object to be exposed having a reference pattern on the surface in one direction;
A plurality of mask patterns arranged above the conveying means and arranged in at least one row; provided on the side of the row of the mask patterns ; and a viewing window for observing the reference pattern of the object to be exposed;該覗-out is formed by matching the center axis on an axis parallel to the central axis at or within sight Madogai columns of the mask pattern window, first and second intersecting at different angles relative to the axis A photomask provided with an alignment mark configured to include a thin line pattern , a central axis of the mask pattern row is substantially perpendicular to a conveyance direction of the object to be exposed, and the viewing window is with respect to the mask pattern row. a mask stage for holding by closely opposed to the subject to be exposed as a transport direction front side of the object to be exposed Te,
A light source that emits exposure light applied to the object to be exposed through the photomask;
Imaging means for the side by side in Kazunao line in a direction substantially perpendicular to the conveying direction of the object to be exposed having a plurality of light receiving elements, for imaging the alignment marks of said photomask,
Processing the image picked up by the image pickup means, measuring an interval between the first and second fine line patterns of the alignment mark to calculate a shift amount of the photomask in the transport direction, and the exposure light; Control means for correcting and controlling the irradiation timing according to the amount of deviation of the photomask;
An exposure apparatus comprising: A transport means for transporting an object to be exposed having a reference pattern on the surface in one direction;
A plurality of mask patterns arranged above the conveying means and arranged in at least one row, and formed on the central axis of the row of the mask patterns or on an axis parallel to the central axis, and the central axis or the axis A photomask provided with an alignment mark including a first fine line pattern extending perpendicularly to the second fine line pattern and a second fine line pattern inclined at a predetermined angle; A mask stage that is held in close proximity to the object to be exposed so that its axis is substantially perpendicular to the conveying direction of the object to be exposed;
A light source that emits exposure light applied to the object to be exposed through the photomask;
An imaging unit that has a plurality of light receiving elements arranged in a straight line in a direction substantially orthogonal to the conveyance direction of the object to be exposed, and that images the alignment mark of the photomask;
Processing the image picked up by the image pickup means, measuring an interval between the first and second fine line patterns of the alignment mark to calculate a shift amount of the photomask in the transport direction, and the exposure light; Control means for correcting and controlling the irradiation timing according to the amount of deviation of the photomask;
An exposure apparatus comprising: 11. The exposure apparatus according to claim 9 , wherein the imaging unit captures a reference pattern provided on the object to be exposed and the alignment mark within the same field of view and simultaneously focuses the images. The control means detects an edge located on the leading side in the conveyance direction of the reference pattern formed on the object to be exposed based on the image picked up by the image pickup means, and after the edge is detected 11. The control according to claim 9 , wherein exposure light is irradiated at a timing when the object to be exposed is moved by a distance obtained by adding and correcting a deviation amount of the photomask to a preset value. Exposure device. The mask stage is formed so as to be able to displace the photomask in a direction substantially orthogonal to the conveying direction of the object to be exposed,
The control unit is configured to, based on the reference pattern and the alignment mark image captured by the imaging unit, the edge of the reference pattern extending in parallel with the transport direction and the first and first alignment marks. of the two fine line patterns, one of the computed distance between the predetermined reference position on the thin line pattern, wherein the distance by driving and controlling the mask stage to a predetermined value The exposure apparatus according to claim 9 or 10 , wherein the photomask is displaced in a direction crossing the transport direction. The exposure apparatus according to claim 9 , wherein the light source is a flash lamp that is controlled by the control unit to be turned on and off.

Images