JP2010160340A - Method for forming spacer, method for manufacturing substrate for display panel, spacer, and substrate for display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming a spacer capable of uniformizing a cell gap, to provide a method for manufacturing a substrate for a display panel, and to provide a substrate for a display panel. <P>SOLUTION: The method includes stages of: forming a film 17 of a photosensitive material on the surface of a substrate 1 for a display panel; irradiating a part of the photosensitive material film 17 removed by development in a later stage with light at first intensity while blocking light in a part of the film corresponding to a spacer 15, and irradiating a region approximately in the center of the region corresponding to the spacer 15 with light at second intensity lower than the first intensity; and forming a recessed part in the region irradiated with light energy at the second intensity in the photosensitive material film 17 by developing the photosensitive material film 17. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for forming a spacer, a method for manufacturing a substrate for a display panel, a spacer, and a substrate for a display panel, and more specifically, a method for forming a spacer for maintaining a cell gap at a predetermined dimension, The present invention relates to a method for manufacturing a substrate for a display panel including a spacer, a spacer for defining a cell gap, and a substrate for a display panel including the spacer.

  A general liquid crystal display panel includes two display panel substrates. For example, in the case of an active matrix type liquid crystal display panel, a TFT array substrate and a color filter are provided as substrates for the display panel. Then, these two display panel substrates are bonded to each other with a predetermined minute interval, and liquid crystal is filled therebetween (that is, the liquid crystal is interposed between the two display panel substrates). Layer is formed).

  If the thickness of the liquid crystal layer (or the distance between two display panel substrates, hereinafter referred to as “cell gap”) is not uniform, unevenness may occur on the screen. Therefore, in order to maintain or improve the display quality of the liquid crystal display panel, it is necessary to maintain the cell gap uniformly over the entire surface of the display panel. Therefore, in general, a configuration is adopted in which the cell gap is uniformly maintained by the spacer.

  For example, a configuration in which the spacer is formed of the same material as a structure that regulates the alignment of liquid crystal (hereinafter referred to as “alignment regulating structure”) may be used. However, since the height of the spacer needs to be higher than the height of the alignment regulating structure, in such a configuration, the spacer may have a laminated structure of two or more stages. That is, first, the lower part of the spacer and the alignment control structure are formed of the same material in the same process. Next, the upper part of the spacer is formed so as to be stacked on the lower part of the previously formed spacer. Thereby, the height of a spacer can be made higher than the height of an orientation control structure.

  As another configuration, a configuration is also proposed in which the spacer is formed of the same material as the colored layer (see Patent Document 1). That is, a columnar spacer is formed by laminating the same material as the colored layer on the surface of the substrate for a display panel.

  By the way, the structure which forms a spacer by laminating | stacking the same material as an orientation control structure may have the following problems. The spacer and the alignment regulating structure are generally made of a photosensitive material. Then, it is formed into a predetermined shape by photolithography. For this reason, a photomask for forming the alignment regulating structure and the lower part of the spacer and a photomask for forming the upper part of the spacer are required. That is, in order to form the spacer, a plurality of photomasks are required. For this reason, the increase in equipment cost is invited. In addition, a process for forming the alignment regulating structure and the lower part of the spacer and a process for forming the upper part of the spacer are required. For this reason, the number of processes increases and the manufacturing cost rises.

  Further, in order to keep the cell gap uniformly over the entire surface of the display panel, it is necessary to make the height and shape of the spacers uniform. However, it has become difficult to make the height and shape of the spacers uniform over the entire surface of the display panel substrate. That is, when the spacer is made of a photosensitive material, the height and shape of the spacer change according to the heating temperature in the heat treatment. For this reason, in order to make the height and shape of the spacers uniform, it is necessary to heat the entire surface of the mother substrate so that the temperature is uniform in the heat treatment. However, with an increase in the area of the mother substrate, it has become difficult to heat the entire surface of the mother substrate to a uniform temperature.

  In addition, the spacer formed of the photosensitive material becomes a spherical shape or a curved shape with a protruding end portion when subjected to heat treatment. When the tips of the spacers are spherical or projecting curved surfaces, the tips of the spacers are easily crushed when the display panel substrates are bonded to each other. When the tip of the spacer is crushed, the height of the spacer is lowered, and it becomes difficult to maintain a predetermined cell gap. Further, if the spacer shape is non-uniform as described above, the way the spacers are crushed also becomes non-uniform. As a result, it becomes difficult to keep the cell gap uniform.

JP-A-9-120075

  In view of the above circumstances, the problem to be solved by the present invention is to provide a spacer forming method, a display panel substrate manufacturing method, a spacer, and a display panel substrate capable of reducing equipment costs and manufacturing costs. Or providing a method for forming a spacer, a method for manufacturing a substrate for a display panel, a spacer, a substrate for a display panel, or securing a predetermined cell gap It is to provide a method for forming a spacer, a method for manufacturing a substrate for a display panel, a spacer, and a substrate for a display panel.

  In order to solve the above-mentioned problems, the present invention provides a method for forming a spacer for defining a cell gap between display panel substrates, wherein a film of a photosensitive material is formed on the surface of the display panel substrate. Irradiating the photosensitive material film with light energy through a first semi-transmissive region formed in a photomask on a region substantially in the center corresponding to the spacer of the photosensitive material film; and developing the photosensitive material film And forming a recess in a region irradiated with light energy through the first semi-transmissive region of the photomask.

  In this case, it is preferable that the developed photosensitive material is heated and softened so that the upper surface is formed in a substantially flat surface.

  As the photosensitive material, a positive photosensitive material can be applied. In this case, the photomask includes a light shielding region corresponding to the spacer and a first semi-transmissive region formed substantially at the center of the light shielding region. And shielding light from the region corresponding to the spacer in the film of the photosensitive material, and irradiating light energy through the first semi-transmissive region to a region substantially in the center corresponding to the spacer. In the development of the film of the photosensitive material, it is preferable to leave the photosensitive material in the region corresponding to the spacer and to form a recess in the region irradiated with light energy through the first semi-transmissive region.

  A method of manufacturing a substrate for a display panel having a spacer for defining a cell gap, comprising: forming a photosensitive material film on a surface of the display panel substrate; and forming the photosensitive material film on the spacer Irradiating light energy through a first semi-transmissive region formed in the photomask to a substantially central region of the corresponding region; and developing the film of the photosensitive material to develop the first half of the photomask. And forming a recess in a region irradiated with light energy through the transmission region.

  In this case, it is preferable to form the upper surface in a substantially flat surface by heating and softening the developed photosensitive material.

  As the photosensitive material, a positive photosensitive material can be applied. In this case, the photomask includes a light shielding region corresponding to the spacer and a first semi-transmissive region formed substantially at the center of the light shielding region. And shielding light from the region corresponding to the spacer in the film of the photosensitive material, and irradiating light energy through the first semi-transmissive region to a region substantially in the center corresponding to the spacer. In the development of the film of the photosensitive material, it is preferable that the photosensitive material is left in the region corresponding to the spacer and the concave portion is formed in the region irradiated with the light energy through the first semi-transmissive region.

  The photomask further includes a second semi-transmissive region corresponding to the pattern of the alignment control structure that controls the alignment of the liquid crystal, and the first semi-transmissive region is passed through the region substantially at the center of the region corresponding to the spacer. It is preferable to irradiate light energy to the region corresponding to the alignment control structure through the second semi-transmissive region simultaneously with the light energy irradiation.

  A method of forming a spacer for defining a cell gap between substrates for a display panel, comprising: forming a photosensitive material film on a surface of the display panel substrate; and a predetermined film of the photosensitive material film. Light having a second intensity that is weaker than the light energy of the first intensity is applied to the area of the photosensitive material film corresponding to the spacer and is irradiated with light energy of the first intensity on the area. Irradiating energy, and developing the photosensitive material film to form a recess in a region of the photosensitive material film irradiated with the second intensity of light energy. It is a summary.

  When the photosensitive material formed on the surface of the display panel substrate is a positive type, the light energy of the first intensity is determined from the surface of the display panel substrate in the development process. Light energy that is strong enough to be completely or almost completely removed. Further, when the photosensitive material formed on the surface of the display panel substrate is a negative type, light that can leave the workable material completely or almost intact on the surface of the display panel in the development process. It refers to energy. The second-strength light energy is light energy that is weaker than the first-strength light energy, and the photosensitive resin material formed on the surface of the display panel substrate is a positive type. Even if it is a case or a negative type, a part of the photosensitive material formed on the surface of the substrate for the display panel can be removed and a part can be left in the development process (that is, development) In the process, it means light energy with such a strength that the thickness of the photosensitive resin material formed on the surface of the substrate for the display panel can be reduced but cannot be completely removed.

  The predetermined region of the photosensitive material film is irradiated with light energy having a first intensity through a light-transmitting region formed on a photomask, and an abbreviation of a region corresponding to the spacer of the photosensitive material film. The center is preferably configured to irradiate light energy having a second intensity that is weaker than the light energy having the first intensity through the first semi-transmissive region formed in the photomask.

  Note that the light-transmitting region formed on the photomask has a configuration in which the intensity of light energy that can be irradiated through the light-transmitting region can be higher than the intensity of light energy that can be irradiated through the semi-transmitting region. Good. That is, the light-transmitting region is not limited to a configuration that transmits light emitted from the light source of the exposure apparatus as it is, for example, and may have a configuration that can adjust (for example, weaken) the intensity of transmitted light energy.

  A positive photosensitive material can be applied to the photosensitive material film. In this case, the predetermined region of the photosensitive material film is a region to be removed by development. The photomask includes a light shielding region corresponding to the spacer, a first semi-transmissive region formed substantially at the center of the light shielding region, and a transparent portion formed in a portion other than the light shielding region and the first semi-transmissive region. Light region. Then, a region corresponding to the spacer in the photosensitive material film is shielded by a light shielding region formed on the photomask, and the predetermined region of the photosensitive material film (that is, a region removed by development). Is irradiated with light energy having a first intensity through a light-transmitting region formed on the photomask, and the photomask is applied to a region of the photosensitive material film at a substantially central region corresponding to the spacer. A second intensity of light energy that is weaker than the first intensity of light energy is irradiated through the formed first semi-transmissive region. Then, the photosensitive material film is developed to leave the photosensitive material film in a region corresponding to the spacer, and a recess is formed in the region irradiated with the second intensity light energy through the first semi-transmissive region. The configuration of performing is applicable.

  It is preferable that the developed photosensitive material film is softened by heating to form a substantially flat upper surface of the developed photosensitive material film.

  The present invention relates to a method for manufacturing a substrate for a display panel having a spacer for defining a cell gap, the step of forming a photosensitive material film on a surface of the display panel substrate, and the photosensitive material film. The second region is irradiated with light energy having a first intensity at a predetermined region and a second strength weaker than the light energy having the first strength at a substantially center of a region corresponding to the spacer of the film of the photosensitive material. Irradiating the light energy of the thickness; and developing a film of the photosensitive material to form a recess in the region of the photosensitive material film irradiated with the second intensity of light energy. It has a gist.

  The predetermined region of the photosensitive material film is irradiated with light energy having a first intensity through a light-transmitting region formed on a photomask, and an abbreviation of a region corresponding to the spacer of the photosensitive material film. A structure in which light energy having a second intensity that is weaker than the light energy having the first intensity is applied to the center through the first semi-transmissive region formed in the photomask can be applied.

  A positive photosensitive material can be applied to the photosensitive material film. In this case, the predetermined region of the photosensitive material film is a region to be removed by development. The photomask includes a light shielding region corresponding to the spacer, a first semi-transmissive region formed substantially at the center of the light shielding region, and a transparent portion formed in a portion other than the light shielding region and the first semi-transmissive region. Light region. Then, a region corresponding to the spacer in the photosensitive material film is shielded by a light shielding region formed on the photomask, and the predetermined region of the photosensitive material film (that is, a region removed by development). Is irradiated with light energy having a first intensity through a light-transmitting region formed on the photomask, and the photomask is applied to a region of the photosensitive material film at a substantially central region corresponding to the spacer. A second intensity of light energy that is weaker than the first intensity of light energy is irradiated through the formed first semi-transmissive region. Then, the photosensitive material film is developed to leave the photosensitive material film in a region corresponding to the spacer, and a recess is formed in the region irradiated with the second intensity light energy through the first semi-transmissive region. The configuration of performing is applicable.

  A configuration in which the developed photosensitive material is heated and softened to form an upper surface of the developed photosensitive material in a substantially flat surface can be applied.

  The photomask further includes a second transflective region corresponding to the pattern of the alignment control structure, and has a second strength through the first transflective region at a substantially central region of the region corresponding to the spacer. A structure in which light energy is irradiated through the second semi-transmissive region to the region corresponding to the alignment control structure at the same time as light energy is applied can be applied.

  The gist of the present invention is a spacer that defines a cell gap between substrates for a display panel. The gist of the present invention is that the upper surface is formed in a substantially flat surface or a recess is formed in the approximate center of the upper surface.

  This spacer preferably has a single-layer structure of a photosensitive material and is formed in a substantially columnar shape.

  The gist of the present invention is a substrate for a display panel, and has a spacer having a top surface formed in a substantially flat surface or a recess formed in a substantially center of the top surface. This spacer preferably has a single-layer structure of a photosensitive material and is formed in a substantially columnar shape.

  Here, the spacer may be formed of the same material as the orientation control structure.

  According to the present invention, the upper surface of the finally formed spacer can be formed into a substantially planar shape or a curved shape with a depressed central portion. The spacer having such a shape is less likely to be crushed even when a compressive force is applied, as compared to a spacer formed with a substantially spherical surface or a curved surface with a protruding upper surface. That is, the spacer formed on the upper surface having a substantially spherical shape or a protruding curved surface has a tapered shape, so that the strength of the narrowed portion is low. For this reason, when a compressive force is applied to the spacer, the tip end portion is crushed and the height tends to be lowered. On the other hand, a curved spacer whose upper surface is substantially flat or whose central portion of the upper surface is depressed has almost the same thickness over the entire length (that is, there is no thin portion), and therefore it is crushed even if a compressive force is applied. Hateful. For this reason, since a deformation | transformation of a spacer is prevented or suppressed, the cell gap of a predetermined dimension is securable.

  In addition, according to the present invention, since the upper surface of the spacer is substantially flat or has a curved shape with the central portion of the upper surface recessed, the shape and height of the spacer are uniform. In other words, the curvature radius and height of the upper surface of a spacer having a substantially spherical surface or a protruding curved surface changes depending on processing conditions such as heating temperature. For this reason, if the processing conditions are not uniform, the height and shape of the spacers are also not uniform. On the other hand, if the upper surface of the spacer is substantially planar or a curved surface with a depressed central portion of the upper surface, the height hardly changes even if the processing conditions are different. Therefore, the height of the spacer can be made uniform, and the cell gap can be kept uniform.

  According to the present invention, the structure that regulates the alignment of the liquid crystal (alignment regulating structure) and the spacer are simultaneously formed in the same process. Therefore, the number of steps can be reduced as compared with a structure formed separately, and the production cost can be reduced.

  In addition, according to the present invention, since the spacer has a single layer structure, the number of photomasks required for formation can be reduced as compared with the spacer having a stacked structure. That is, since a spacer can be formed by one exposure and one development using a single photomask, the number of photomasks can be reduced as compared with a configuration in which a spacer having a stacked structure is formed. The number of processes can be reduced. Therefore, it is possible to reduce the equipment cost and the manufacturing cost.

It is the figure which showed typically the structure of the board | substrate for display panels concerning embodiment of this invention, (a) is the perspective view which showed the whole structure, (b) is the plane which showed one structure of the pixel FIG. 4C is a cross-sectional view taken along the line AA of FIG. 5B, showing a cross-sectional structure of the picture element. It is sectional drawing which showed typically the structure of the spacer concerning embodiment of this invention, (a) shows the structure by which an upper surface is formed in a substantially plane, (b) shows the structure by which a recessed part is formed in an upper surface. Show. It is sectional drawing which showed the predetermined | prescribed process of the formation method of the spacer concerning embodiment of this invention. It is the figure which showed typically the structure of the photomask used when forming the spacer of this invention, (a) is a top view, (b) is sectional drawing. It is sectional drawing which showed the predetermined process (exposure process) of the formation method of the spacer concerning embodiment of this invention. It is sectional drawing which showed the predetermined process (development process) of the formation method of the spacer concerning embodiment of this invention. It is sectional drawing which showed typically the predetermined | prescribed process of the manufacturing method of the board | substrate for display panels concerning embodiment of this invention. It is sectional drawing which showed typically the predetermined | prescribed process of the manufacturing method of the board | substrate for display panels concerning embodiment of this invention. It is sectional drawing which showed typically the predetermined | prescribed process of the manufacturing method of the board | substrate for display panels concerning embodiment of this invention. It is sectional drawing which showed typically the predetermined | prescribed process of the manufacturing method of the board | substrate for display panels concerning embodiment of this invention. It is sectional drawing which showed typically the predetermined | prescribed process of the manufacturing method of the board | substrate for display panels concerning embodiment of this invention. It is sectional drawing which showed typically the predetermined | prescribed process of the manufacturing method of the board | substrate for display panels concerning embodiment of this invention. It is sectional drawing which showed typically the predetermined | prescribed process of the manufacturing method of the board | substrate for display panels concerning embodiment of this invention.

  Embodiments of the present invention will be described below in detail with reference to the drawings. A substrate for a display panel according to an embodiment of the present invention is a color filter for a liquid crystal display panel.

  FIG. 1A is a plan view schematically showing the entire structure of a display panel substrate 1 according to an embodiment of the present invention, and FIG. 1B is a diagram for a display panel according to an embodiment of the present invention. FIG. 1C is a plan view showing one of the picture elements formed on the substrate 1. FIG. 1C is a cross-sectional view taken along line AA of FIG. FIG.

  As shown in FIGS. 1A, 1B, and 1C, a display panel substrate 1 according to an embodiment of the present invention has a black matrix 12 and a predetermined color on the surface of a transparent substrate 11. The layer 13, the common electrode 14, the alignment regulating structure 16, and the spacer 15 are formed.

  As shown in FIGS. 1A and 1B, the black matrix 12 is a lattice-like structure, and is formed of, for example, a photosensitive material (for example, a photosensitive resin composition) containing a black colorant. . This black matrix 12 can have the same configuration as the black matrix of various known color filters. Therefore, detailed description is omitted.

  In a region partitioned by the black matrix 12 (that is, inside each lattice formed by the black matrix 12), colored layers 13 of red, green, and blue are formed. The colored layer 13 is formed of a resin composition containing red, green, and blue colorants.

  A common electrode 14 is formed on the surfaces of the black matrix 12 and the colored layer 13 (see particularly FIG. 1C). The common electrode 14 is formed of a transparent conductive material. For example, indium tin oxide (ITO) can be applied to the transparent conductive material.

  As shown in FIGS. 1B and 1C, an alignment regulating structure 16 is formed on the surface of the common electrode 14. The alignment regulating structure 16 is a convex structure for regulating the alignment of the liquid crystal. The alignment regulating structure 16 is formed of a photosensitive material (that is, a resist material, such as a photosensitive resin composition).

  Spacers 15 are formed at positions overlapping the black matrix 12 on the surface of the common electrode 14. The spacer 15 is a columnar structure for defining a cell gap. FIG. 1B shows a configuration in which the spacer 15 is formed in a substantially cylindrical shape, but the shape of the spacer 15 is not particularly limited. For example, the spacer 15 may be formed in a quadrangular prism shape or an octagonal prism shape.

  FIG. 2 is a cross-sectional view schematically showing the configuration of the spacer 15 according to the embodiment of the present invention. FIG. 2A shows the spacer 15 whose upper surface is formed in a substantially flat surface. FIG. 2B shows the spacer 15 having a recess formed on the upper surface. As shown in FIGS. 2A and 2B, the spacer 15 according to the embodiment of the present invention is a columnar structure formed on the display panel substrate 1. The spacer 15 has a single layer structure of a photosensitive material (for example, a photosensitive resin composition made of an acrylic resin or the like). That is, the spacer 15 is not formed by laminating a plurality of photosensitive material films, but is integrally formed by a single photosensitive material. As shown in FIG. 2A, the upper surface of the spacer 15 is formed in a substantially flat surface, or as shown in FIG. 2B, the substantially center of the upper surface of the spacer 15 is formed in a depressed shape. .

  The spacer 15 according to the embodiment of the present invention is less likely to be crushed even when a compressive force is applied, as compared to a spacer formed with a substantially spherical surface or a curved surface with a protruding upper surface. That is, the spacer formed in a substantially spherical shape or a curved surface with a protruding upper surface has a tapered shape. Therefore, when a compressive force is applied, the thinned portion tends to be crushed and the height tends to be lowered. On the other hand, the spacer 15 having a substantially flat upper surface or a curved surface with a depressed central portion of the upper surface has substantially the same thickness over the entire length (that is, there is no thin portion). It is hard to be crushed. For this reason, since the deformation of the spacer 15 is prevented or suppressed, a cell gap having a predetermined dimension can be secured.

  A method of forming the spacer 15 having such a configuration is as follows. 3, 5, and 6 are cross-sectional views schematically showing each step of the method for forming the spacer 15.

  First, as shown in FIG. 3, the surface of the transparent substrate 11 (that is, the display panel substrate 1 according to the embodiment of the present invention) on which the black matrix 12, the colored layer 13, and the common electrode 14 are formed is photosensitive. A film 17 of a material (for example, a photosensitive resin composition made of an acrylic resin) is formed. The photosensitive material film 17 has a single-layer structure made of a single material. For example, a slit coater is used to form the photosensitive material film 17. The photosensitive material may be a positive type or a negative type, but is assumed to be a positive type in the embodiment of the present invention.

  Next, the formed photosensitive material film 17 is subjected to an exposure process. FIGS. 4A and 4B are diagrams showing a part necessary for forming the spacer 15 extracted from the photomask 9 used in the exposure process. FIG. 4A is a plan view and FIG. 4B is a cross-sectional view. It is.

  As shown in FIGS. 4A and 4B, the photomask 9 can transmit a part of the light energy, a light-transmitting region 91 through which light energy can be transmitted, a light-shielding region 92 that blocks light energy, and the like. That is, the first semi-transmissive region 93a is formed, which can reduce the intensity of transmitted light energy. Specifically, a light shielding region 92 having a shape substantially equal to the shape of the spacer 15 is formed at a position corresponding to the position where the spacer 15 is formed. For example, when forming a cylindrical spacer, as shown in FIG. 4A, a substantially circular light shielding region 92 is formed. A first semi-transmissive region 93 a is formed at the approximate center of the light shielding region 92. Further, a light transmitting region 91 is formed in a region corresponding to a region where the spacer 15 is not formed (that is, a region where the photosensitive material film 17 is removed by development).

  Note that the light transmitting region 91 formed in the photomask 9 has a light energy intensity that can be irradiated through the light transmitting region 91 more than the light energy intensity that can be irradiated through the first semi-transmissive region 93a. As long as the configuration can be strong. That is, the translucent region 91 is not limited to a configuration that transmits light emitted from the light source of the exposure apparatus as it is, for example, and may have a configuration that can adjust (for example, weaken) the intensity of transmitted light energy. .

  FIG. 5 is a cross-sectional view schematically showing the exposure process. As shown in FIG. 5, a photomask 9 is overlaid on the transparent substrate 11 on which the photosensitive material film 17 is formed. Then, an exposure process is performed on the film 17 of the photosensitive material through the photomask 9 (the arrow in the figure schematically shows the light energy to be irradiated). When the exposure process is performed through the photomask 9, as shown in FIG. 5, the region corresponding to the translucent region 91 in the film 17 of the photosensitive material is irradiated with light energy having the first intensity. . A region corresponding to the light shielding region 92 is not irradiated with light energy. The region corresponding to the first semi-transmissive region 93a is irradiated with light energy having the second intensity.

  When the photosensitive material film 17 is made of a positive photosensitive material (that is, a positive resist), the light energy having the first intensity is a photosensitive material film in a later development step. This is the intensity of light energy that can provide the exposure necessary and sufficient to completely or substantially remove 17. The light energy having the second intensity is light energy that is weaker than the light energy having the first intensity, and a part of the film 17 of the photosensitive material can be removed in a later development process. (That is, the thickness of the film 17 of the photosensitive material can be reduced in the developing step). The light energy emitted from the light source of the exposure machine is transmitted through the first semi-transmissive region 93a of the photomask 9, so that the intensity is weakened to become the light energy of the second intensity.

  The light energy transmitted through the light transmitting region of the photomask 9 is applied to the film 17 of the photosensitive material as light energy having the first intensity. The light energy transmitted through the first translucent region 93a of the photomask 9 is weakened and irradiated to the photosensitive material film 17 as light energy of the second intensity.

  Next, development processing is performed on the film 17 of the photosensitive material that has been subjected to the exposure processing. FIG. 6 is a cross-sectional view showing a film 17 of a photosensitive material that has been subjected to development processing. As shown in FIG. 6, when the development process is performed, a portion of the photosensitive material film 17 irradiated with light energy of the first intensity through the light-transmitting region 91 of the photomask 9 is removed. . The film 17 of the photosensitive material remains in the portion where the light energy is blocked by the light shielding region 92 (that is, the portion where the light energy is not irradiated). Further, although the photosensitive material film 17 remains in the portion exposed through the first semi-transmissive region 93 a, the thickness thereof is lower than the portion shielded by the light shielding region 92. As a result, as shown in FIG. 6, the columnar photosensitive material remains on the surface of the display panel substrate 1. The remaining columnar photosensitive material becomes the spacer 15. The approximate center of the upper surface of the spacer 15 is irradiated with light energy having a second intensity through the first semi-transmissive region 93a of the photomask 9, and thus becomes thinner than the light-shielded portion. As a result, a recess is formed on the upper surface.

  Next, the photosensitive material that has been subjected to development processing is subjected to heat treatment. The photosensitive material is softened when heated to a temperature equal to or higher than the glass transition point, and is deformed by surface tension. Here, when the upper surface of the photosensitive material (that is, the spacer 15) left on the surface of the display panel substrate 1 is substantially flat (that is, when a recess is not formed at the approximate center of the upper surface), the surface tension The upper surface is hemispherical or has a curved surface. However, when the concave portion is formed at the center of the upper surface, it is possible to prevent or suppress the upper surface from protruding upward.

  For this reason, the upper surface of the columnar photosensitive material after heating (that is, the spacer 15) is substantially flat as shown in FIG. 2 (a), or the central part is slightly depressed as shown in FIG. 2 (b). It becomes a curved surface. The final shape of the upper surface of the spacer 15 depends on the thickness of the central portion of the columnar photosensitive material (spacer 15) left by the developing process, the heating temperature and the heating time in the heating process, and the like. Therefore, the final shape of the spacer 15 can be set by adjusting these appropriately.

  According to such a configuration, the shape and height of the spacer 15 can be made uniform. In other words, the curvature radius and height of the upper surface of a spacer having a substantially spherical surface or a protruding curved surface changes depending on processing conditions such as heating temperature. For this reason, if the processing conditions are not uniform, the height and shape of the spacers are also not uniform. On the other hand, if the upper surface of the spacer 15 is substantially flat or has a curved shape with a depressed central portion, the height hardly changes even if the processing conditions are different. Therefore, the heights of the spacers 15 can be made uniform, and the cell gap can be kept uniform.

  Further, since the spacer 15 has a single layer structure of a photosensitive material, the number of photomasks required for formation can be reduced as compared with a spacer having a laminated structure. That is, the spacer 15 can be formed by one exposure and one development using one photomask 9. Therefore, the number of photomasks and the number of processes can be reduced as compared with the case where a spacer having a laminated structure of photosensitive materials is formed. Therefore, it is possible to reduce the equipment cost and the manufacturing cost.

  In the above-described embodiment, a configuration in which a positive photosensitive material is applied is shown, but a configuration in which a negative photosensitive material (that is, a negative resist) may be applied. In the case where the photosensitive material film 17 is made of a negative photosensitive material, the first intensity of light energy completely cures the photosensitive material film 17 in a later development step. Or it is the light energy of the intensity | strength which can give a sufficient exposure amount necessary to leave almost as it is. The light energy having the second intensity is light energy that is weaker than the light energy having the first intensity, and a part of the film 17 of the photosensitive material can be removed in a later development process. (That is, the thickness of the film 17 of the photosensitive material can be reduced in the developing step). The light energy emitted from the light source of the exposure device is transmitted through the first semi-transmissive region of the photomask, so that the intensity is weakened to become the light energy having the second intensity.

  When the photosensitive material film 17 is made of a negative photosensitive material, the photomask used in the exposure process is a photomask used when the photosensitive material film 17 is made of a positive photosensitive material. A photomask having a configuration in which the light transmitting region and the light shielding region are interchanged is used. The pattern of the first semi-transmissive region has the same pattern whether the photosensitive material film 17 is made of a negative photosensitive material or a positive photosensitive material. The light energy emitted from the light source of the exposure device is transmitted through the first semi-transmissive region of the photomask, so that the intensity is weakened to become the light energy having the second intensity.

  Referring to FIG. 4, a light-transmitting region having a shape substantially equal to the shape of the spacer 15 is formed at a position corresponding to the position where the spacer 15 is formed (the light-blocking region 92 shown in FIG. To replace). At the approximate center of the light transmitting region, a first semi-transmissive region (the first semi-transmissive region 93a shown in FIG. 4 becomes the first semi-transmissive region as it is), and a region where the spacer 15 is not formed ( That is, a light-shielding region is formed in a region corresponding to a region where the photosensitive material film 17 is removed by development (the light-transmitting region 91 shown in FIG. 4 is replaced with the light-shielding region).

  Of the photosensitive material film 17 formed on the surface of the substrate for the display panel, the portion left in the development process (that is, the portion serving as a spacer) is first through a light-transmitting region formed in the photomask. Irradiate with light energy of intensity. Further, the portion to be removed in the development process is shielded from light by a light-transmitting region formed on the photomask and is not irradiated with light energy. A light spot having a second intensity that is weaker than the light intensity having the first intensity is irradiated to a portion (that is, a concave portion) having a low height at the center of the spacer 15 through the first semi-transmissive region.

  With such a configuration, a spacer 15 having a configuration as shown in FIG. 6 is obtained.

  Next, a manufacturing method of the display panel substrate 1 according to the embodiment of the present invention will be described. 7 to 13 are cross-sectional views schematically showing each step of the method for manufacturing the display panel substrate 1 according to the embodiment of the present invention. The manufacturing process of the display panel substrate 1 according to the embodiment of the present invention includes a black matrix forming process, a colored layer forming process, and a transparent electrode (common electrode) forming process. In addition, these figures are typical for description, and are not cut along a specific cutting line.

  As shown in FIG. 7, a black matrix 12 is formed on the surface of a transparent substrate 11 made of glass or the like. The formation method of the black matrix 12 is, for example, as long as it is a resin BM method. First, a layer of a photosensitive resin composition (also referred to as “BM resist”) containing a black colorant is formed on the surface of the transparent substrate 11. Next, the formed BM resist is patterned into a predetermined pattern by a photolithography method or the like. Thereby, a grid-like black matrix 12 is formed.

  As shown in FIG. 8, in the colored layer forming step, colored layers 13 of red, green, and blue colors for color display are formed. An ink jet printer is used to form the colored layer 13. That is, using an ink jet printer, a resin material containing a colorant of a predetermined color is dropped onto each region partitioned by the black matrix 12 (that is, inside each lattice of the black matrix 12). The dropped resin material is solidified. Thereby, the colored layer 13 of each color is formed.

  As shown in FIG. 9, in the common electrode forming step, the common electrode 14 is formed on the surfaces of the black matrix 12 and the colored layer 13. For example, if it is a masking method, a mask will be arrange | positioned on the surface of the transparent substrate 11 which passed the said process, and a transparent conductive material is vapor-deposited by sputtering etc. Thereby, a common electrode 14 having a predetermined pattern is formed at a predetermined position on the transparent substrate 11. Further, according to the photolithography method, a film of a conductive material is formed on the surface of the transparent substrate 11 that has undergone the above steps, and the formed film of the conductive material is patterned into a predetermined pattern by etching. For this patterning, wet etching using ferric chloride can be applied. Indium tin oxide (ITO) can be applied to the transparent conductive material.

  Next, the spacer 15 and the alignment regulating structure 16 are simultaneously formed in the same process. Specifically, it is as follows.

  First, as shown in FIG. 10, a film 17 of a photosensitive material (for example, a photosensitive resin composition made of an acrylic resin) is formed on the surface of the common electrode 14. For forming the photosensitive material film 17, for example, a method of applying a photosensitive material by a slit coater can be applied. Here, an example in which the photosensitive material film 17 is made of a positive photosensitive material will be described.

  Then, as shown in FIG. 11, the formed photosensitive material film 17 is exposed using a predetermined photomask 9. The photomask 9 includes a light-transmitting region 91, a light-shielding region 92 and a first semi-transmissive region 93a for forming the spacer 15, and a second semi-transmissive region 93b for forming the alignment regulating structure 16. And are formed. The light transmissive region 91 can transmit light energy. The light shielding region 92 can block light energy. The first semi-transmissive region 93a and the second semi-transmissive region 93b can weaken the intensity of transmitted light energy.

  A portion of the photosensitive material film 17 to be removed in a later development process is irradiated with light energy having a first intensity through the light-transmitting region 91 of the photomask 9. In addition, the portion of the photosensitive material film 17 that becomes the spacer 15 is shielded from light by the light shielding region 92 of the photomask 9, and the second region through the first semi-transmissive region 93 a is provided at the approximate center of the region that becomes the spacer 15. The light energy of the intensity is irradiated. The portion that becomes the alignment regulating structure 16 is irradiated with light energy through the second semi-transmissive region 93 b of the photomask 9.

  The intensity of light energy irradiated through the second semi-transmissive region 93b of the photomask 9 is light energy that is weaker than the light energy of the first intensity, and in the subsequent development process, The intensity of light energy is such that a part of the material film 17 can be removed and a part can be left (that is, the thickness of the film 17 of the photosensitive material can be reduced in the developing process). Specific strength is set according to the height of the alignment control structure 16 to be formed.

  Next, development processing is performed on the film 17 of the photosensitive material that has been subjected to the exposure processing. As shown in FIG. 12, when the development process is performed, a portion of the photosensitive material film 17 irradiated with light energy of the first intensity through the light-transmitting region 91 of the photomask 9 is removed, A portion shielded by the light shielding region 92 of the photomask 9 (that is, a portion not irradiated with light energy) remains. Further, a portion of the photomask 9 irradiated with light energy of the second intensity through the first semi-transmissive region 93a and a light intensity of the first intensity through the second semi-transmissive region 93b of the photomask 9 The part irradiated with light energy of weak intensity remains. For this reason, the columnar spacer 15 and the alignment regulating structure 16 having a predetermined pattern remain on the surface of the display panel substrate 1.

  In the photosensitive material film 17, the portion of the photomask 9 that is irradiated with light energy having the second intensity through the first semi-transmissive region 93 a is thicker than the portion that is shielded by the light shielding region 92. Becomes thinner. For this reason, the thickness of the approximate center of the upper surface of the columnar spacer 15 is reduced, and a recess is formed at the approximate center of the upper surface. Similarly, the portion irradiated with energy weaker than the light intensity of the first intensity through the second semi-transmissive region 93b of the photomask 9 is thinner than the portion shielded by the light shielding region 92. Become. For this reason, the height of the alignment regulating structure 16 is lower than the height of the spacer 15.

  Even when the photosensitive material film 17 is made of a negative photosensitive material, the spacer 15 and the alignment regulating structure 16 having the above-described configuration can be formed. When the photosensitive material film 17 is made of a negative photosensitive material, the photomask used in the exposure step is a photomask used when the photosensitive material film 17 is made of a positive photosensitive material; The light-transmitting area and the light-shielding area are interchanged. The pattern of the first semi-transmissive region for forming the concave portion in the center of the spacer 15 and the pattern of the second semi-transmissive region for forming the alignment regulating structure 16 are such that the photosensitive material film 17 is negative. Whether the photosensitive material is made of a positive photosensitive material, it has the same pattern.

  That is, with reference to FIG. 11, the light shielding region 92 of the photomask 9 shown in FIG. 11 is light-transmitting in a photomask used when a film of a photosensitive material is formed of a negative photosensitive material. It becomes an area. A light-transmitting region 91 of the photomask 9 shown in FIG. 11 is a light-shielding region in a photomask used when the photosensitive material film is formed of a negative photosensitive material. The pattern of the first semi-transmissive region for forming the concave portion in the center of the spacer 15 and the pattern of the second semi-transmissive region for forming the alignment regulating structure 16 are such that the photosensitive material film 17 is negative. Whether the photosensitive material is made of a positive photosensitive material, it has the same pattern.

  The portion of the photosensitive material film 17 that is removed in the subsequent development process is shielded by the light shielding region of the photomask and is not irradiated with light energy. In the later development process, the remaining portion (that is, the portion that becomes the spacer 15) is irradiated with light energy having the first intensity through the light transmitting region. Light energy having the second intensity is applied to the approximate center of the region to be the spacer 15 through the first semi-transmissive region. Light energy is applied to the portion serving as the alignment regulating structure 16 through the second transflective region of the photomask.

  The intensity of the light energy irradiated through the second translucent region of the photomask is light energy having a weaker intensity than the light intensity of the first intensity. The light energy is strong enough to remove a part of the film 17 and leave a part (that is, the thickness of the film 17 of the photosensitive material can be reduced in the developing process). Specific strength is set according to the height of the alignment control structure 16 to be formed.

  Next, development processing is performed on the film 17 of the photosensitive material that has been subjected to the exposure processing. As shown in FIG. 12, when the development process is performed, a portion of the photosensitive material film 17 irradiated with light energy having the first intensity through the light-transmitting region of the photomask remains. A portion shielded by the light shielding region (that is, a portion not irradiated with light energy) is removed. In addition, a portion irradiated with light energy of the second intensity through the first semi-transmissive region of the photomask and an intensity weaker than the light energy of the first strength through the second semi-transmissive region of the photomask. The portion irradiated with the light energy remains. For this reason, the columnar spacer 15 and the alignment regulating structure 16 having a predetermined pattern remain on the surface of the display panel substrate 1.

  Of the photosensitive material film 17, the portion of the photomask irradiated with light energy of the second intensity through the first semi-transmissive region is thicker than the portion irradiated with light energy through the light-transmitting region. Becomes thinner. For this reason, the thickness of the approximate center of the upper surface of the columnar spacer 15 is reduced, and a recess is formed at the approximate center of the upper surface. Similarly, a portion irradiated with light energy less than the first intensity light energy through the second transflective region of the photomask has a thickness that is larger than a portion irradiated with light energy through the light transmitting region. getting thin. For this reason, the height of the alignment regulating structure 16 is lower than the height of the spacer 15.

  As described above, even when the photosensitive material film 17 is made of a negative photosensitive material, the spacer 15 and the alignment regulating structure 16 having the same structure as that of the positive photosensitive material are formed. be able to.

  Next, the film 17 of the photosensitive material that has been subjected to the development process (that is, the spacer 15 and the alignment regulating structure 16) is subjected to heat treatment. FIG. 13 is a cross-sectional view schematically showing the structure of the spacer 15 and the alignment regulating structure 16 that have been subjected to heat treatment. When the photosensitive material is heated to a temperature higher than the glass transition temperature, the formed spacer 15 and alignment regulating structure 16 are softened and deformed by surface tension. As described above, since the concave portion is formed in the central region of the upper surface of the spacer 15, the upper surface is substantially flat or has a shape in which the approximate center of the upper surface is recessed. On the other hand, the orientation regulating structure 16 has a substantially semicircular cross section or a curved shape projecting upward.

  Through the above steps, the display panel substrate 1 according to the embodiment of the present invention is manufactured.

  According to the embodiment of the present invention, the alignment regulating structure 16 that regulates the alignment of the liquid crystal and the spacer 15 are simultaneously formed in the same process. Therefore, the number of steps can be reduced as compared with a structure formed separately, and the production cost can be reduced.

  The embodiments of the present invention have been described in detail with reference to the drawings. However, the present invention is not limited to the embodiments, and various modifications can be made without departing from the spirit of the present invention. It goes without saying that it is possible.

DESCRIPTION OF SYMBOLS 1 Substrate for display panels 11 Transparent substrate 12 Black matrix 13 Colored layer 14 Common electrode 15 Spacer 16 Orientation control structure 17 Photosensitive resin composition layer 9 Photomask 91 Translucent area 92 Light-shielded area 93a First semi-transmissive area 93b Second translucent region

Claims (21)

A method of forming a spacer for defining a cell gap between substrates for a display panel,
Forming a photosensitive material film on the surface of the display panel substrate;
Irradiating light energy through a first semi-transmissive region formed in a photomask on a region substantially in the center corresponding to the spacer of the film of the photosensitive material; and
Forming a recess in a region irradiated with light energy through the first translucent region of the photomask by developing the film of photosensitive material;
A method for forming a spacer, comprising:   2. The method of forming a spacer according to claim 1, wherein the developed photosensitive material is heated and softened to form a substantially flat upper surface. The photosensitive material is a positive photosensitive material,
The photomask has a light shielding region corresponding to the spacer and a first semi-transmissive region formed substantially at the center of the light shielding region,
The region corresponding to the spacer is shielded from the film of the photosensitive material, and light energy is irradiated through the first semi-transmissive region to a region substantially in the center corresponding to the spacer,
The photosensitive material is left in a region corresponding to a spacer in development of the film of the photosensitive material, and a concave portion is formed in a region irradiated with light energy through the first semi-transmissive region. Item 3. A method for forming a spacer according to Item 2. A method of manufacturing a substrate for a display panel having a spacer that defines a cell gap,
Forming a photosensitive material film on the surface of the display panel substrate;
Irradiating light energy through a first semi-transmissive region formed in a photomask on a region substantially in the center corresponding to the spacer of the film of the photosensitive material; and
Forming a recess in a region irradiated with light energy through the first transflective region of the photomask by developing the film of photosensitive material;
A method for manufacturing a substrate for a display panel, comprising:   5. The method for manufacturing a substrate for a display panel according to claim 4, wherein the developed photosensitive material is heated and softened to form a substantially flat upper surface. The photosensitive material is a positive photosensitive material,
The photomask has a light shielding region corresponding to the spacer and a first semi-transmissive region formed substantially at the center of the light shielding region,
The region corresponding to the spacer is shielded from the film of the photosensitive material, and light energy is irradiated through the first semi-transmissive region to a region substantially in the center corresponding to the spacer,
5. The photosensitive material is left in a region corresponding to a spacer in the development of the photosensitive material film, and a concave portion is formed in a region irradiated with light energy through the first semi-transmissive region. Item 6. A method for producing a substrate for a display panel according to Item 5.   The photomask further includes a second semi-transmissive region corresponding to the pattern of the alignment control structure that controls the alignment of the liquid crystal, and the first semi-transmissive region is passed through the region substantially at the center of the region corresponding to the spacer. 7. The method of manufacturing a substrate for a display panel according to claim 6, wherein light energy is irradiated to a region corresponding to the orientation control structure simultaneously with light energy through the second semi-transmissive region. A method of forming a spacer for defining a cell gap between substrates for a display panel,
Forming a photosensitive material film on the surface of the display panel substrate;
A predetermined area of the photosensitive material film is irradiated with light energy of a first intensity, and the light intensity of the first intensity is applied to the approximate center of the area corresponding to the spacer of the film of photosensitive material. Irradiating light energy of weak second intensity,
Forming a recess in a region of the photosensitive material film irradiated with light energy of the second intensity by developing the photosensitive material film; and
A method for forming a spacer, comprising:   The predetermined region of the photosensitive material film is irradiated with light energy having a first intensity through a light-transmitting region formed on a photomask, and an abbreviation of a region corresponding to the spacer of the photosensitive material film. The light intensity of the second intensity that is weaker than the light intensity of the first intensity is irradiated to the center through the first semi-transmissive region formed in the photomask. Spacer forming method. The photosensitive material film is made of a positive photosensitive material,
The predetermined area of the photosensitive material film is an area to be removed by development;
The photomask is formed in a light shielding region corresponding to the spacer, a first semi-transmissive region formed substantially at the center of the light shielding region, and a portion other than the light shielding region and the first semi-transmissive region. A translucent region,
A region corresponding to the spacer of the photosensitive material film is shielded by a light shielding region formed on the photomask, and a transparent region formed on the photomask is formed on the predetermined region of the photosensitive material film. A light energy having a first intensity is irradiated through the light region, and the first portion of the film of the photosensitive material corresponding to the spacer is substantially centered in the region through the first semi-transmissive region formed in the photomask. Irradiate light energy of a second intensity that is weaker than light energy of one intensity,
The photosensitive material film is developed to leave a photosensitive material film in a region corresponding to the spacer, and a recess is formed in a region irradiated with light energy of a second intensity through the first semi-transmissive region. The method of forming a spacer according to claim 9.   11. The developed photosensitive material film is heated and softened to form a substantially flat upper surface of the developed photosensitive material film. A method for forming a spacer as described in 1. above. A method of manufacturing a substrate for a display panel having a spacer that defines a cell gap,
Forming a photosensitive material film on the surface of the display panel substrate;
A predetermined area of the photosensitive material film is irradiated with light energy of a first intensity, and the light intensity of the first intensity is applied to the approximate center of the area corresponding to the spacer of the film of photosensitive material. Irradiating light energy of weak second intensity,
Forming a recess in the region of the photosensitive material film irradiated with the second intensity of light energy by developing the photosensitive material film; and
A method for manufacturing a substrate for a display panel, comprising:   The predetermined region of the photosensitive material film is irradiated with light energy having a first intensity through a light-transmitting region formed on a photomask, and an abbreviation of a region corresponding to the spacer of the photosensitive material film. 13. The light energy having a second intensity that is weaker than the light energy having the first intensity is irradiated to the center through the first transflective region formed in the photomask. A method for manufacturing a substrate for a display panel. The photosensitive material is a positive photosensitive material,
The predetermined area of the photosensitive material film is an area to be removed by development;
The photomask includes a light-shielding region corresponding to the spacer, a first semi-transmissive region formed substantially at the center of the light-shielded region, and a light-transmitting region formed in a portion other than the light-shielding region and the first semi-transmissive region. And
A region corresponding to the spacer in the photosensitive material film is shielded by a light shielding region formed on the photomask, and a transparent region formed on the photomask is formed in the predetermined region of the photosensitive material film. A light energy having a first intensity is irradiated through the light region, and the first portion of the photosensitive material film corresponding to the spacer is substantially centered in a region corresponding to the spacer through the first translucent region. Irradiate light energy of a second intensity that is weaker than light energy of one intensity,
Developing the photosensitive material film to leave a photosensitive material film in a region corresponding to the spacer, and forming a recess in a region irradiated with light energy of a second intensity through the first semi-transmissive region. A method for manufacturing a substrate for a display panel according to claim 13.   15. The display panel according to claim 12, wherein an upper surface of the developed photosensitive material is formed in a substantially flat surface by heating and softening the developed photosensitive material. Of manufacturing a substrate for the use.   The photomask further includes a second transflective region corresponding to the pattern of the alignment control structure, and has a second strength through the first transflective region at a substantially central region of the region corresponding to the spacer. 16. The display panel according to claim 12, wherein light energy is irradiated through the second semi-transmissive region simultaneously with light energy irradiation to a region corresponding to the alignment control structure. Substrate manufacturing method.   A spacer for defining a cell gap between substrates for a display panel, wherein an upper surface is formed in a substantially flat surface or a recess is formed in a substantially center of the upper surface.   The spacer according to claim 17, wherein the spacer has a single-layer structure of a photosensitive material and is formed in a substantially columnar shape.   A substrate for a display panel, characterized in that the upper surface is formed in a substantially flat surface or has a spacer in which a recess is formed in the approximate center of the upper surface.   20. The display panel substrate according to claim 19, wherein the spacer has a single layer structure of a photosensitive material and is formed in a substantially columnar shape.   21. The display panel substrate according to claim 19, wherein the spacer is made of the same material as the alignment control structure.

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