JP2006235515A - Photomask and method for manufacturing display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a display panel having a small contact hole. <P>SOLUTION: The method for manufacturing a display panel includes a contact hole forming step of forming a contact hole in at least one layer in layers formed on the surface of a substrate. The contact hole forming step includes steps of applying a resist film on the surface of one layer, exposing the resist film through a photomask and developing to form a first opening in the resist film corresponding to the contact hole. The exposure step is carried out by using a photomask 2 having a main pattern 41 corresponding to the contact hole with addition of a first auxiliary pattern 42. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a photomask and a display panel.

  Some display devices have a display panel and a housing for housing the display panel, such as a liquid crystal display device and an organic EL display device. The display panel includes a substrate, and a plurality of pixels are formed on the surface of the substrate. The display panel displays a video, an image, and the like by driving each pixel.

  Some display panels have a structure in which a thin film layer is stacked on a surface of a substrate in order to form pixels or drive elements for driving the pixels. As a manufacturing method for forming such a laminate, there is a method called a photolithography method.

  In the photolithography method, a resist film made of a photosensitive material is arranged on the surface of one layer, and light is irradiated to a region corresponding to a shape to be manufactured. Next, for example, in the case of a positive resist film, when the portion irradiated with light is removed by development, an opening is formed in the shape of the portion irradiated with light. Next, the one layer can be formed into a desired shape by performing etching or the like on the one layer through the opening of the resist film.

  In the step of irradiating light to the resist film, light is irradiated using an exposure apparatus. The exposure apparatus includes a photomask, and light is irradiated through the photomask. For example, the photomask includes a reticle of an exposure apparatus. The photomask is formed, for example, so as to irradiate light into a region having a shape to be processed. In the exposure apparatus, the image formed on the photomask is enlarged or reduced, and the resist film is exposed to a desired shape.

  Japanese Patent Laid-Open No. 2003-75988 discloses a reticle pattern forming method. 18 to 23 are explanatory diagrams relating to the reticle disclosed in Japanese Patent Laid-Open No. 2003-75988.

  FIG. 18 shows a schematic plan view of one pattern data corresponding to the exposure pattern formed on the reticle. FIG. 19 shows a schematic plan view of an exposure pattern of a reticle formed with one pattern data.

  Referring to FIGS. 18 and 19, pattern data 71 is formed such that corner portions are substantially perpendicular. Based on the pattern data 71, an exposure pattern 72 is formed on the photomask. In the exposure pattern 72, the convex corner portion is rounded, and the rounded corner portion is generated in the concave corner portion.

  FIG. 20 shows a schematic plan view of another pattern data. In the other pattern data 73, a square exposure pattern is added to the convex corner portion, and a square exposure pattern is deleted from the concave corner portion. It is disclosed that by using the pattern data 73, it is possible to suppress a round portion of the corner of the exposure pattern of the reticle to be a shape approximate to the original exposure pattern.

  FIG. 21 shows a schematic plan view of another pattern data. FIG. 22 shows a schematic plan view of an exposure pattern of a reticle formed with different pattern data. As shown in FIG. 21, when pattern data 74 having a substantially square planar shape is used, as shown in FIG. 22, the exposure pattern 75 formed on the reticle has rounded corners of the square of the planar shape. Become.

  FIG. 23 shows a schematic plan view of still another pattern data. The pattern data 76 has a planar shape formed in a substantially square shape, and a substantially square pattern data is added to a corner portion. By adding pattern data to corner portions, the shape of the exposure pattern formed on the reticle can be brought close to the original square shape.

As described above, Japanese Patent Laid-Open No. 2003-75988 discloses that the shape of a corner portion can be accurately reproduced by adding or deleting pattern data to the corner portion.
JP 2003-75988 A

  As represented by the display panel of a television receiver, the display panel has been increased in size, while the display panel has been reduced in size, such as a mobile phone. In the downsizing of the display panel, in addition to the downsizing of the pixels in the respective display areas, there is a demand for downsizing of drive drivers and the like arranged outside the display areas.

  Along with the miniaturization of the display panel, there is a demand for miniaturization of the opening of the resist film in the photolithography method. The method of processing one layer after exposing the resist film to form an opening in the resist film is used for forming a point-like contact hole in addition to the formation of a line-like wiring. The contact hole is an opening formed so as to penetrate an arbitrary layer among a plurality of stacked layers. An electrode is formed on the surface of the contact hole, or a wiring penetrating each layer by filling the inside of the contact hole with a conductive substance is formed.

  When an opening is formed in a part of the resist film and a contact hole is formed using this opening, the planar shape of the opening formed in the resist film is desired as the diameter of the contact hole decreases. Going away from the shape, it becomes difficult to form a small opening in the resist film. That is, in the step of forming the contact hole, if the shape of the exposure pattern of the photomask is reduced, the diameter of the contact hole to be formed becomes smaller, and eventually the formation of the contact hole becomes difficult. Although it is conceivable to reduce the diameter of the opening by shortening the wavelength of the light source of the exposure apparatus, there is a problem that a new exposure apparatus must be introduced.

  In the reticle exposure pattern forming method disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2003-75988, although it is disclosed that the corners of the exposure pattern formed on the reticle are prevented from being rounded, the resist There is no description regarding downsizing of the opening formed in the film.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a photomask capable of forming a small contact hole and a method for manufacturing a display panel having a small contact hole.

  The method of manufacturing a display panel according to the present invention includes a contact hole forming step of forming a contact hole in at least one layer among layers formed on the surface of the substrate, and the contact hole forming step includes a resist on the surface of the single layer. A step of arranging a film, an exposure step of exposing the resist film through a photomask, and a development step of performing development to form a first opening corresponding to the contact hole in the resist film. Including. In the exposure step, the photomask in which the first auxiliary pattern is added to the main pattern corresponding to the contact hole is used. By adopting this method, a method for manufacturing a display panel having the small contact hole can be provided. Alternatively, the contact hole can be formed with high accuracy corresponding to the size of the main pattern.

  Preferably, in the above invention, the photomask includes a step of forming a line pattern on the one layer, and the exposure step uses the photomask in which a second auxiliary pattern is added to a corner portion of the main pattern corresponding to the line pattern. . The developing step includes a step of forming a second opening corresponding to the line pattern in the resist film. By adopting this method, the shape of the line pattern can be brought close to the design value, and the line pattern can be miniaturized.

  Preferably, in the above invention, an imaging type exposure apparatus is used for exposure in the exposure step, and the photomask having a width of the main pattern of 4 μm or less is used. By adopting this method, the effect of accurately forming the contact hole with respect to the main pattern becomes remarkable.

  Preferably, in the above invention, the planar shapes of the main pattern corresponding to the contact hole and the first auxiliary pattern are each formed in a quadrangular shape, and the portion that becomes the corner of the main pattern corresponding to the contact hole when viewed in plan The first auxiliary pattern is disposed in By adopting this method, the main pattern and the first auxiliary pattern corresponding to the contact hole can be easily formed.

  In the above invention, a liquid crystal display panel is preferably manufactured as the display panel. By adopting this method, the present invention can be applied to a method for manufacturing a liquid crystal display panel.

  In order to achieve the above object, a photomask according to the present invention includes an exposure pattern for forming a contact hole, and the exposure pattern includes a main pattern and an auxiliary pattern, and the auxiliary pattern is seen in a plan view. Are arranged at the corners of the main pattern. By adopting this configuration, a photomask for forming the small contact hole can be provided.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the photomask which can form a small contact hole, and the display panel which has a small contact hole can be provided.

  With reference to FIG. 1 to FIG. 18, a method for manufacturing a photomask and a display panel according to an embodiment of the present invention will be described. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

  The display panel in the present embodiment is a liquid crystal display panel. The liquid crystal display panel in this embodiment is an active matrix liquid crystal display panel including a TFT (Thin Film Transistor) substrate.

  FIG. 1 shows an enlarged schematic cross-sectional view of a surface portion of a TFT substrate on which a TFT is formed in the liquid crystal display panel of the present embodiment. FIG. 2 is an enlarged schematic plan view of a portion of the liquid crystal display panel where the TFT is formed.

  1 and 2, a silicon layer 25 is formed on the surface of a glass substrate 21 as a substrate. A gate insulating layer 22 is formed on the surface of the silicon layer 25 so as to cover the silicon layer 25. A gate electrode 26 is disposed above a substantially central portion in the width direction of the silicon layer 25 via a gate insulating layer 22. An interlayer insulating layer 23 is formed on the surfaces of the gate insulating layer 22 and the gate electrode 26.

  A contact hole 32 is formed on the side of the gate electrode 26 so as to penetrate the gate insulating layer 22 and the interlayer insulating layer 23. The contact hole 32 has the gate electrode 26 disposed on both sides. An electrode layer 24 is disposed on the surface of the contact hole 32. The electrode layer 24 is disposed along the side wall of the contact hole 32 and the surface of the silicon layer 25. The electrode layer 24 is disposed so as to contact the silicon layer 25. In the silicon layer 25, an impurity implantation region is formed so as to correspond to a region where the contact hole 32 is formed (not shown).

  Referring to FIG. 2, gate electrode 26 is formed to extend from gate bus line 27. In the present embodiment, the contact hole 32 is formed so that the planar shape thereof is substantially square. The electrode layer 24 is formed so as to cover the contact hole 32.

  The electrode layer 24 on the side that becomes the drain electrode of the electrode layer 24 is connected to the pixel electrode. A pixel electrode is arranged on the upper side of the stacked body shown in FIG. 1 by laminating a planarization insulating film or the like (not shown). Further, in the liquid crystal display panel of the present embodiment, TFTs are formed in circuits such as drivers of each pixel and the panel peripheral portion.

  3 to 5 show enlarged schematic cross-sectional views of each step of the display panel manufacturing method according to the present embodiment.

  As shown in FIG. 3, a silicon layer 25 is formed on the surface of a glass substrate 21 as a substrate. A gate insulating layer 22 is formed so as to cover the silicon layer 25. Further, a gate electrode 26 is formed on the surface of the gate insulating layer 22. An interlayer insulating layer 23 is formed on the surfaces of the gate electrode 26 and the gate insulating layer 22.

  Next, a contact hole forming step for forming contact holes in the gate insulating layer 22 and the interlayer insulating layer 23 is performed. A photosensitive resist film 28 is disposed on the surface of the interlayer insulating layer 23. The resist film 28 may be a positive type or a negative type. In the present embodiment, a positive resist film 28 is used. An exposure process of irradiating the resist film 28 with light through a photomask is performed using an exposure apparatus. In the exposure step of the present embodiment, light is irradiated to a region where a contact hole is to be formed as indicated by an arrow 82.

  Next, as shown in FIG. 4, a first opening 35 corresponding to the contact hole is formed in the resist film 28 by performing a development process.

  Next, as shown in FIG. 5, contact holes 32 are formed in the gate insulating layer 22 and the interlayer insulating layer 23 by etching, for example, from above the resist film 28. The contact hole 32 is formed so as to reach the silicon layer 25. Thereafter, an electrode layer is formed and the display panel shown in FIG. 1 is manufactured.

  FIG. 6 shows an enlarged schematic plan view of an exposure pattern for forming a contact hole in the photomask used in the exposure process of the present embodiment. An exposure pattern 40 is formed on the photomask 2. The exposure pattern 40 includes a main pattern 41 having a substantially square planar shape and an auxiliary pattern 42 having a substantially square planar shape. In the present embodiment, the light is transmitted through a region inside the exposure pattern.

  The auxiliary pattern 42 is disposed at a portion that becomes a square corner of the planar shape of the main pattern 41. The auxiliary pattern 42 is arranged so that the center of gravity of the square overlaps with the corner of the main pattern 41 when viewed in plan. Further, when viewed in plan, the main pattern 41 and the auxiliary pattern 42 are arranged so that their sides are substantially parallel to each other. The auxiliary pattern 42 is arranged such that the length δ of the portion overlapping the main pattern 41 when viewed in plan is half the length 2δ of one side of the auxiliary pattern 42.

  In the exposure process, by using a photomask having an exposure pattern in which the first auxiliary pattern is added to the main pattern corresponding to the shape of the contact hole, the diameter of the contact hole that can be formed in the same exposure apparatus is reduced. Can do.

  FIG. 7 is an enlarged schematic plan view when contact holes are formed in the resist film using the photomask in this embodiment mode. An opening 36 is formed in the resist film 28. As shown in FIG. 6, the main pattern 41 of the exposure pattern 40 has a square shape, but the opening 36 has a shape in which a corner portion is rounded and close to a circle. When the same exposure apparatus is used, the diameter of the opening 36 is smaller than the diameter of the opening that can be formed by the conventional technique.

  In the present invention, the “diameter” means a diameter when the planar shape is substantially circular in a plan view, and when the planar shape is substantially square, the shorter one of the distances between opposing sides Indicates the length. In other shapes, the smallest length of the lines passing through the center of gravity of the planar shape is the diameter of the shape. Moreover, when the main pattern and the auxiliary pattern are formed in the exposure pattern of the photomask, the diameter of the exposure pattern indicates the diameter of the main pattern.

  In the present embodiment, the planar shapes of the main pattern and the first auxiliary pattern corresponding to the contact holes are each formed into a quadrangle. By adopting this method, it is possible to form a small contact hole with an exposure pattern with a simple structure.

  With reference to FIG. 8 to FIG. 13, a study on the downsizing of the contact hole in the present embodiment will be described.

  FIG. 8 is an enlarged schematic plan view of a conventional photomask, and FIG. 9 is a plan view of an opening of a resist film formed using the photomask. An exposure pattern 43 having a substantially square planar shape is formed on the photomask 3. When the diameter L1a of the exposure pattern 43 is reduced using such a photomask, the planar shape of the opening 37 formed in the resist film 29 approaches a circle. The diameter L1b of the opening 37 at this time is preferably the same as the diameter L1a of the exposure pattern 43 in the photomask 3. However, when the diameter L1a of the exposure pattern 43 is reduced, it is observed that the diameter L1b of the opening 37 of the resist film 29 decreases away from the diameter L1a.

  In the present invention, the minimum value at which the diameter of the exposure pattern formed on the photomask is approximately the same as the diameter of the opening formed in the resist film is referred to as “minimum compatible dimension”.

  Consider a case where an exposure apparatus equipped with a mercury lamp is used using a photomask based on the prior art shown in FIG. The mercury lamp has spectral peaks of i-line (365 nm), h-line (405 nm) and g-line (436 nm). Of the three spectral peaks, the i-line wavelength is the shortest. Using the g-line and h-line of the mercury lamp, the minimum compatible dimension when using the photomask 3 shown in FIG. 8 is 4 μm.

  FIG. 10 and FIG. 11 are explanatory diagrams when the i-line of the mercury lamp is used. FIG. 10 shows an enlarged schematic plan view of a photomask used in this test, and FIG. 11 shows an enlarged schematic plan view of a resist film formed using this photomask.

  A contact hole having a small diameter can be formed by shortening the wavelength of light for exposure. An exposure pattern 44 having a substantially square planar shape is formed on the photomask 4. By reducing the diameter L2a of the exposure pattern 44, the planar shape of the opening 38 of the resist film 30 to be formed becomes close to a circular shape. At this time, the minimum conforming dimension in which the diameter L2b of the opening 38 and the diameter L2a of the exposure pattern 44 are substantially equal was 2 μm.

  In this manner, the contact hole can be reduced in size by shortening the wavelength of light for exposure. However, when the wavelength of the exposure apparatus is shortened, the time for performing exposure becomes longer. For example, the throughput (processing capacity per unit time) when using the i-line shown in FIGS. 10 and 11 is about half of the throughput when using the g-line and h-line shown in FIGS. End up. In order to shorten the wavelength of light of the exposure apparatus and make the throughput the same, it is necessary to use a large number of apparatuses, and there is a problem that the working place becomes large. In addition, when a short wavelength exposure apparatus is used, there is a problem that the price of the exposure apparatus per unit increases and the price of the display panel increases.

  FIG. 12 is an enlarged schematic plan view of a photomask in which the first auxiliary pattern in this embodiment is formed, and FIG. 13 is a schematic plan view of an opening of a resist film formed using this photomask. . On the photomask 5, an exposure pattern 40 is formed which includes a main pattern having a square shape in a square shape and a first auxiliary pattern having a square shape in a square shape.

  FIG. 13 shows a planar shape of the opening when the diameter L3a of the exposure pattern 40 is reduced. The opening 39 formed in the resist film 31 has a planar shape close to a circular shape. When the g-line and h-line of the mercury lamp are used, the minimum conforming dimension in which the diameter L3b of the opening 39 is substantially the same as the diameter L3a of the exposure pattern 40 of the photomask 5 is 3 μm or less, and the first auxiliary pattern A smaller opening can be formed than in the case of an exposure mask that does not form a film. The throughput at this time is the same as the performance test shown in FIGS. 8 and 9 because the g-line and the h-line of the light from the mercury lamp are used.

  Thus, the diameter of the contact hole to be formed can be reduced using the same exposure apparatus without reducing the processing capability. That is, in the present invention, the exposure is performed using a photomask having an exposure pattern in which an auxiliary pattern is formed on the main pattern, so that the contact of the exposure apparatus is maintained without shortening the wavelength of light while maintaining productivity. The hall can be downsized.

  The resolution is indicated by k × (λ / NA) (k: process factor depending on the type of photosensitive resin, λ: wavelength of light for exposure, NA: numerical aperture). NA indicates the degree to which the lens for performing exposure collects the spread light and depends on the characteristics of the lens. λ depends on the light to be exposed. In the present invention, by adding an auxiliary pattern to the main pattern, the process factor k can be changed and the processing dimension can be reduced. As a result, the contact hole can be reduced in size.

  Furthermore, by using a photomask having an exposure pattern in which the first auxiliary pattern is added to the main pattern corresponding to the contact hole, a contact hole having a shape close to the design value can be formed. Referring to FIG. 2, for example, when the contact hole 32 has the same area when viewed in plan, the contact hole 32 is preferably shaped along the planar shape of the outer edge of the electrode layer 24. An arrow 80 and an arrow 81 are distances from the contact hole 32 to the outer edge of the electrode layer 24. This distance becomes a manufacturing margin (manufacturing margin) when the electrode layer 24 is disposed in the contact hole 32. By forming the contact hole 32 in a shape close to the design value, the distance indicated by the arrows 80 and 81 can be increased, and the manufacturing margin can be increased.

  Further, the method may include a step of forming a line pattern in the layer for forming the contact hole, and a step of forming a second opening corresponding to the line pattern in the resist film for forming the contact hole. At this time, it is preferable to use a photomask in which the second auxiliary pattern is added to the corner of the main pattern corresponding to the shape of the line pattern in the exposure process. By adopting this method, the shape of the corner portion of the line pattern can be brought close to the design, and the line pattern can be miniaturized. As a result, the display panel can be reduced in size.

  For example, it is preferable to add a second auxiliary pattern having a square planar shape to a convex corner when the line pattern is viewed in plan. Although the convex corner portion is rounded only with the main pattern, the corner portion can be brought close to the design shape by forming the auxiliary pattern.

  FIG. 14 shows a schematic layout of the display panel. A display area 51 is set on the main surface of the glass substrate 54. The display area 51 is a part where a plurality of pixels are formed. The display area 51 is formed so that the planar shape is a quadrangle. On the side of the display area 51, an area for arranging a driver for driving the TFT in each pixel is set. The outside of the display area 51 is also called a frame area, and a driver is arranged in the frame area. In FIG. 14, the gate driver arrangement area 52 is set on the left side and the source driver arrangement area 53 is set on the lower side of the display area 51.

  For example, by using CGS (continuous grain boundary Si) as the silicon film, the display region portion and the driver can be simultaneously formed on the surface of the substrate. In the process of forming the driver, there is a process of forming a contact hole or the like using a resist film.

  Therefore, the present invention not only reduces the size of the pixels in the display area, but also contributes to reducing the area of the driver arranged in the frame area. That is, by adopting the manufacturing method or the photomask according to the present invention, it is possible to reduce the size of a driver IC (Integrated Circuit) and to reduce the driver arrangement area. In FIG. 14, the gate driver arrangement area 52 and the source driver arrangement area 53 can be reduced, and the frame area in the display panel can be reduced. As a result, the display panel can be reduced in size.

  Next, with reference to FIGS. 15 to 17, a performance test when the main pattern of the exposure pattern and the size of the first auxiliary pattern are changed will be described.

  FIG. 15 is a schematic plan view of a test piece used for the performance test, and FIG. 16 is a schematic cross-sectional view of the test piece used for the performance test. As the test piece, a test piece having the same configuration as the stacked state of the contact hole portion of the TFT of the display panel in this embodiment was formed. A silicon layer 61 is formed on the surface of the glass substrate 60. A gate insulating layer 62 is formed on the surface of the silicon layer 61. An interlayer insulating layer 63 is formed on the surface of the gate insulating layer 62. A plurality of contact holes 64 are formed so as to penetrate the gate insulating layer 62 and the interlayer insulating layer 63. In forming the contact hole 64, a plurality of through holes are formed so as to be arranged in a lattice pattern.

  In the performance test, a resist film containing a novolac resin as a main component is used. Further, as the exposure apparatus, a stepper type out of the imaging type exposure apparatus is used.

  The exposure pattern of the photomask used for forming the contact hole 64 includes an exposure pattern 40 (see FIG. 6) including the main pattern 41 and the first auxiliary pattern 42, and an exposure pattern having no first auxiliary pattern. did.

  Referring to FIG. 6, in the performance test, the width W of the main pattern 41 (corresponding to the diameter of the exposure pattern) was changed by a minimum of 0.5 μm within a range from 2.0 μm to 9.0 μm. . Further, the first auxiliary pattern was changed by a minimum of 0.25 μm within the range of the length δ from 0 μm to 1.0 μm. The length δ is the length of a square side where the main pattern and the auxiliary pattern overlap when the sides of the main pattern and the first auxiliary pattern are extended. The length of one side of the first auxiliary pattern is 2δ.

  A length δ of 0 μm indicates that the first auxiliary pattern is not formed. That the length δ is 0.75 μm indicates that the length of one side of the first auxiliary pattern is 1.5 μm (2 × 0.75 μm). Using these photomasks, the test pieces were exposed to form contact holes. The diameter of the formed contact hole is shown in Table 1 below.

  As a result of the performance test, a contact hole having a small diameter that could not be formed without adding the first auxiliary pattern could be formed by adding the first auxiliary pattern. For example, when there is no first auxiliary pattern (δ = 0), a contact hole having a diameter of 3 μm could not be formed, but a first auxiliary pattern having a length δ of 0.75 μm is formed. As a result, a contact hole having a diameter of 3 μm could be formed with high accuracy.

  When the width W of the main pattern is constant, the diameter of the contact hole can be increased as the auxiliary pattern length δ increases. For example, when the width W of the main pattern is 2.5 μm and the length δ of the first auxiliary pattern is 0.5 μm, the diameter of the contact hole is 1.62 μm, but the length of the first auxiliary pattern is By setting δ to 1.0 μm, a contact hole having a diameter of 3.53 μm could be formed.

  FIG. 17 shows a graph of the results of the performance test. The horizontal axis is the diameter of the exposure pattern of the photomask, and the vertical axis is the diameter of the contact hole formed. The diameter of the opening formed in the resist film and the diameter of the contact hole formed can be accurately matched by using, for example, a dry etching method.

  In both cases where the exposure pattern includes the first auxiliary pattern and when the first auxiliary pattern does not exist, when the width (exposure pattern diameter) W of the main pattern of the photomask is 7.0 μm or more, the main pattern of the exposure pattern The width W and the diameter of the contact hole formed are approximately the same. That is, the contact hole can be formed almost as designed.

  On the other hand, when the width W of the main pattern becomes smaller than 7.0 μm, the diameter of the contact hole becomes smaller as the width W of the main pattern becomes smaller when there is no first auxiliary pattern (when the length δ is 0 μm). It becomes smaller than the width W of the main pattern. That is, the diameter of the contact hole goes away from the design. From this result, the diameter of the minimum conforming dimension when the first auxiliary pattern was not formed was 7.0 μm.

  On the other hand, when the first auxiliary pattern having a length δ of 0.75 μm or less is formed, the width W of the main pattern of the exposure pattern is formed when the width W of the main pattern of the photomask is 4 μm or more. The diameter of the contact hole is almost the same size. Therefore, by forming the first auxiliary pattern, the minimum conforming dimension can be made 4.0 μm or less.

  For example, when the first auxiliary pattern having a length δ of 0.75 μm is formed, contact holes having substantially the same diameter as the width W of the main pattern are formed until the width W of the main pattern of the photomask is approximately 2 μm. can do. That is, the minimum conforming dimension can be 2 μm.

  In consideration of manufacturing errors (stability of pattern processing) when developing, the minimum diameter of the exposure pattern allowed when the first auxiliary pattern is not formed is 4 μm. When the auxiliary pattern is formed, the minimum allowable exposure pattern diameter can be 3 μm or less. As described above, in the present invention, it is possible to form a contact hole that is smaller than that of the prior art using the same exposure apparatus.

  Furthermore, in the present invention, the contact hole to be formed can be enlarged by increasing the width of the first auxiliary pattern. For example, referring to Table 1 and FIG. 17, when the width δ of the main pattern of the photomask is 5 μm or less by setting the length δ of the first auxiliary pattern to 1.0 μm or more, the main pattern of the exposure pattern The diameter of the contact hole formed can be made larger than the width W of.

  In the present embodiment, the planar shapes of the main pattern and the first auxiliary pattern corresponding to the contact holes are each formed in a quadrangle, but the present invention is not limited to this, and the exposure pattern of the photomask is arbitrary. Shapes can be used. In this case, a small contact hole can be formed by arranging the auxiliary pattern at the corner of the main pattern.

  In this embodiment mode, a liquid crystal display panel has been described as an example of a display panel. However, the present invention is not limited to this mode, and the present invention can be applied to a display panel having a contact hole. For example, the present invention can be applied to an organic EL (Electro Luminescence) display panel.

  In this embodiment, the stepper type exposure apparatus is used as the imaging type exposure apparatus, but the present invention is not limited to this type, and the same effect can be obtained even if a scanning type or mirror projection type imaging exposure apparatus is used. Can do.

  In addition, the said embodiment disclosed this time is an illustration in all the points, Comprising: It is not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and includes all modifications within the scope and meaning equivalent to the terms of the claims.

It is an expansion schematic sectional drawing of the part of TFT of the display area in the liquid crystal display panel of embodiment. It is an expansion schematic plan view of the TFT part of the display area in the liquid crystal display panel of an embodiment. It is 1st process explanatory drawing of the manufacturing method of the liquid crystal display panel in embodiment. It is 2nd process explanatory drawing of the manufacturing method of the liquid crystal display panel in embodiment. It is 3rd process explanatory drawing of the manufacturing method of the liquid crystal display panel in embodiment. It is an expansion schematic plan view of the exposure pattern of the photomask in embodiment. It is an expansion schematic plan view of the opening part of the resist film formed in embodiment. It is an expansion schematic plan view of the exposure pattern of the 1st comparative example in embodiment. It is an expansion schematic plan view of the opening part of the resist film of the 1st comparative example in embodiment. It is an expansion schematic plan view of the exposure pattern of the 2nd comparative example in embodiment. It is an expansion schematic plan view of the opening part of the resist film of the 2nd comparative example in embodiment. It is an expansion schematic plan view of the exposure pattern of the photomask in embodiment. It is an expansion schematic plan view of the opening part of the resist film formed using the photomask in embodiment. It is explanatory drawing of the area | region where drive IC is arrange | positioned among the board | substrates of a liquid crystal display panel. It is a schematic plan view of the test piece of the performance test in embodiment. It is a schematic sectional drawing of the test piece of the performance test in embodiment. It is a graph explaining the result of the performance test in embodiment. It is a schematic plan view of the 1st pattern data based on a prior art. It is a schematic plan view of the exposure pattern of the photomask based on a prior art. It is a schematic plan view of the 2nd pattern data based on a prior art. It is a schematic plan view of the 3rd pattern data based on a prior art. It is a schematic plan view of the exposure pattern of the photomask based on a prior art. It is a schematic plan view of the 4th pattern data based on a prior art.

Explanation of symbols

  2-5 photomask, 21, 54, 60 glass substrate, 22,62 gate insulating layer, 23, 63 interlayer insulating layer, 24 electrode layer, 25, 61 silicon layer, 26 gate electrode, 27 gate bus line, 28-31 Resist film, 32, 64 contact hole, 35-39, 64 opening, 40, 43, 44, 72, 75 exposure pattern, 41 main pattern, 42 auxiliary pattern, 51 display area, 52 gate driver placement area, 53 source driver Arrangement area, 71, 73, 74, 76 pattern data, 80, 81, 82 arrow, L1a, L1b, L2a, L2b, L3a, L3b diameter.

Claims (6)

A contact hole forming step of forming a contact hole in at least one of the layers formed on the surface of the substrate;
The contact hole forming step includes a step of disposing a resist film on the surface of the one layer,
An exposure step of exposing the resist film through a photomask;
Developing, and forming a first opening corresponding to the contact hole in the resist film,
The exposure process uses a photomask in which a first auxiliary pattern is added to a main pattern corresponding to the contact hole. Forming a line pattern in the one layer;
The exposure step uses the photomask in which a second auxiliary pattern is added to a corner portion of the main pattern corresponding to the line pattern,
The display panel manufacturing method according to claim 1, wherein the developing step includes a step of forming a second opening corresponding to the line pattern in the resist film. In the exposure of the exposure step, using an imaging exposure apparatus,
The method for manufacturing a display panel according to claim 1, wherein the photomask having a diameter of the main pattern of 4.0 μm or less is used. The main pattern corresponding to the contact hole and the planar shape of the first auxiliary pattern are each formed into a quadrangle,
The method for manufacturing a display panel according to claim 1, wherein the first auxiliary pattern is disposed at a corner of the main pattern corresponding to the contact hole when seen in a plan view.   The method for manufacturing a display panel according to claim 1, wherein a liquid crystal display panel is manufactured as the display panel. With an exposure pattern to form contact holes,
The exposure pattern includes a main pattern and an auxiliary pattern,
The auxiliary pattern is a photomask arranged at a corner of the main pattern when seen in a plan view.

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