JP3813508B2 - Active matrix substrate, composite active matrix substrate, and display device and detection device using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an active matrix substrate suitably used for a display device such as an organic EL display device and a liquid crystal display device (LCD), and a detection device for detecting various two-dimensional information and two-dimensional distribution information, and the active matrix substrate. In particular, the present invention relates to a composite active matrix substrate formed by connecting a plurality of the end portions to each other, and a display device and a detection device using the composite active matrix substrate.
[0002]
[Prior art]
  An active matrix substrate is an electronic component in which fine structures such as electrical wiring and switching elements are arranged two-dimensionally (matrix) on the surface of an insulating substrate such as a glass substrate. It is widely applied to various display devices and detection devices.
[0003]
  In recent years, both the display device and the detection device have been required to increase the display area and the detection area and to improve the display quality and the detection quality. However, in order to meet the above requirements, there are three problems in the technical field of active matrix substrates: (1) high definition, (2) large area, and (3) versatility of manufacturing equipment.
[0004]
  (1) High definition
  As described above, since various metal wirings and thin film transistors (TFTs) as switching elements are formed on the surface of the active matrix substrate with high definition, advanced fine processing techniques such as photolithography are used. . Nevertheless, in the manufacturing process, some defects due to disconnection of electrical wiring, defects in switching elements, and the like occur.
[0005]
  Therefore, if the active matrix substrate is further refined, the fine structure per unit area may increase, and even if the above-mentioned advanced microfabrication technology is used, the yield rate in the manufacturing process is significantly reduced. . In addition, the manufacturing process is complicated due to high definition. As a result, the manufacturing cost of the active matrix substrate increases.
[0006]
  (2) Increase in area
  When the area of the active matrix substrate is increased, the absolute number of fine structures is increased, so that the yield rate is remarkably reduced and the manufacturing process is complicated as in the case (1). As a result, the manufacturing cost of the active matrix substrate also increases.
[0007]
  (3) Versatile manufacturing facilities
  Once a manufacturing facility for manufacturing an active matrix substrate is constructed, an active matrix substrate larger than the size suitable for the manufacturing facility cannot be manufactured. Therefore, it is practically impossible to manufacture an active matrix substrate with a large area using existing manufacturing equipment, and a new manufacturing equipment must be constructed.
[0008]
  However, the manufacturing equipment generally tends to increase in scale because the manufacturing process of the active matrix substrate is complicated. Therefore, it is difficult to construct a new manufacturing facility every time the active matrix substrate is enlarged.
[0009]
  Therefore, in recent years, as a technique that can cope with the above problems (1) to (3), a method of forming one large substrate, that is, a “composite active matrix substrate” using a plurality of active matrix substrates has been proposed. . In the following description, for convenience, the composite active matrix substrate is appropriately referred to as “composite substrate”, and individual active matrix substrates constituting the composite substrate are appropriately referred to as “unit substrates”.
[0010]
  As a technology related to the composite active matrix substrate, for example, Document (A): “Large Area Liquid Crystal Display Realized by Tiling of Four Back Panels (Proceedings of the 15th International Display Research Conference (ASIA DISPLAY '95.) Pp. 201- 204, 1995) ”and literature (B): US Pat. No. 5,827,757.
[0011]
  The above document (A) discloses a composite substrate used for an LCD and a manufacturing method thereof. As shown in FIGS. 7A to 7C, this composite substrate is formed by bonding four small-sized unit substrates 101 on a single support substrate 102.
[0012]
  Specifically, first, four small-sized unit substrates 101 are placed on a stage 103 with a vacuum chuck in a state where an element forming surface (Active Face) 101a faces downward, and each unit substrate 101 is placed. Align. Thereafter, one support substrate (Base Glass Plate) 102 is bonded to the back side of the unit substrate 101 (upper side in FIG. 7A) with an adhesive resin 105. Here, since the spacer 104 is mixed in the adhesive resin 105, a cell gap is secured between the support substrate 102 and the unit substrate 101. Then, the composite substrate is manufactured by curing the adhesive resin 105.
[0013]
  On the other hand, Document (B) discloses a method for manufacturing a composite substrate and an X-ray detection apparatus using the composite substrate. Similarly to the above-mentioned document (A), this composite substrate is also formed by bonding a plurality of small-sized unit substrates 111 onto a single support substrate 112, as shown in FIG. 8 (g).
[0014]
  Specifically, as shown in FIG. 8A, a substrate having an element formation surface covered with a protective film 121 is used as the unit substrate 111. As shown in FIG. The edge portion (edge portion) is cut by dicing and then polished. Next, as shown in FIG. 8C, the stage 113 is arranged in such a manner that the unit substrates 111 are arranged so that the element forming surfaces face downward and the cut end portions (end surfaces) are connected to each other. Place on top and align. Thereafter, as shown in FIG. 8D, the gap between the two substrates is filled with an adhesive resin 141 to connect the two substrates. After that, as shown in FIG. 8E, one support substrate 112 is bonded to the back surface of the plurality of unit substrates 111 (the upper side in FIG. 8D) with an adhesive resin 131. A large number of through holes 112 a are formed in the support substrate 112. Then, as shown in FIG. 8 (f), after removing the unit substrate 111 (and the support substrate 112 arranged opposite to it) from the stage 113, the protective film 121 is peeled off as shown in FIG. 8 (g). Thus, the composite substrate is manufactured.
[0015]
  In particular, as is apparent from the technique of the above-mentioned document (B), the edge of the display device or the like manufactured using only one active matrix substrate is necessary. Since the end portions of the unit substrates are connected to each other, the edge portion is not necessary.
[0016]
  Moreover, the composite substrate is required to have a substantially constant overall pixel pitch. That is, when the pixel pitch of the connection portion between the unit substrates is larger than the pixel pitch of other portions, not only the connection portion becomes conspicuous, but also when used in a display device, the image quality is used in the detection device. In some cases, the detection accuracy may be reduced.
[0017]
  For this reason, in the technology of the composite active matrix substrate, the unit substrates must be connected with high definition so that the pixel pitch of the connection portion between the unit substrates is equal to or close to that of the other portions. Therefore, high precision is required in the cutting process so that the edge part can be cut as close as possible to the pixel electrode in the vicinity of the side (to be referred to as the edge part) which is a connection part in each unit substrate. The Therefore, a dicing method using a diamond blade is generally used for cutting the edge portion.
[0018]
  By the way, as one of active matrix substrates for LCD applications, for example, a substrate having a Pixel on Passivation structure (hereinafter referred to as a POP structure for convenience of description) as disclosed in Japanese Patent No. 2,598,420 is known. ing. The POP structure refers to a structure in which an insulating film (interlayer insulating film) is formed between the active matrix layer and the pixel electrode layer. When an active matrix substrate having a POP structure is used, the filling rate of pixel electrodes per pixel can be improved, so that the non-display area can be reduced and the image quality can be improved.
[0019]
[Problems to be solved by the invention]
  However, when a composite substrate is formed using the active matrix substrate having the POP structure, there arises a problem that a “film floating defect” occurs in which the insulating film at the cutting site is lifted with the cutting of the edge portion.
[0020]
  The film floating failure will be specifically described with reference to FIGS. 9 (a) and 9 (b).
[0021]
  As shown in FIG. 9A, in the unit substrate 151 having the POP structure, an active matrix layer 154 including a TFT element 160 is formed on a support substrate 152, and an insulating film 155 is further stacked thereon, and further, A pixel electrode layer 156 including a plurality of pixel electrodes 156a is stacked thereon.
[0022]
  When the edge portion of the unit substrate 151 is cut by the dicing blade 153, a fine chip defect 157 occurs in the entire cut edge of the unit substrate 151 as shown in FIG. 9B. This chipping defect 157 is also called chipping, burr or peeling. In the following description, the “chip defect” is expressed as “chipping”.
[0023]
  The chipping 157 is generated when the abrasive grains contained in the dicing blade 153 collide with the cutting edge of the substrate. Therefore, the chipping 157 is always generated when the unit substrate 151 is cut regardless of the POP structure. It is bad. However, the width of the chipping 157 can be controlled within a range of 10 to 30 μm by optimizing the grain size of the abrasive grains and the cutting conditions.
[0024]
  On the other hand, when the unit substrate 151 having the POP structure is cut, a film floating defect 158 in which the insulating film 155 is lifted from the active matrix layer 154 occurs. Specifically, when the side surface 153a of the dicing blade 153 contacts the insulating film 155 when cutting the unit substrate 151, the insulating film 155 is lifted from the active matrix layer 154 by being dragged by the side surface 153a of the rotating dicing blade 153. . The film floating defect 158 may occur with a width of 50 μm or more. Therefore, the film floating defect 158 affects the pixels adjacent to the cutting edge 159.
[0025]
  Therefore, when the edge portion of the unit substrate 151 is cut, it is difficult to bring the cutting position close to the pixel electrode 156a adjacent to the cutting edge 159. As a result, when the composite substrate is formed, the pixel pitch is larger in the connection portion between the unit substrates 151 than in other portions, and the connection portion becomes conspicuous. Furthermore, since the film floating defect 158 may spread over time, the reliability of the composite substrate decreases.
[0026]
  In order to avoid the occurrence of the film floating defect 158, the material of the insulating film 155 must be changed or the generated film floating defect 158 must be repaired, which complicates the manufacturing process of the composite substrate. End up.
[0027]
  The present invention has been made in view of the above problems, and an object of the present invention is to provide an active matrix substrate suitable for manufacturing a composite active matrix substrate, which prevents film floating defects that occur at the time of cutting the edge portion. An object of the present invention is to provide a high-quality and reliable composite active matrix substrate using the same, and a display device and a detection device using the composite active matrix substrate.
[0028]
[Means for Solving the Problems]
  In order to solve the above problems, an active matrix substrate according to the present invention is formed on the surface of an insulating substrate, and includes an active matrix layer including switching elements and electric wirings arranged in a matrix, and the active matrix layer on the active matrix layer. An active matrix substrate comprising: an insulating film formed on the substrate; and a pixel electrode layer formed on the insulating film and including a plurality of pixel electrodes arranged in a matrix.The insulating film is an organic film mainly composed of an organic polymer,At least one side of the periphery of the active matrix substrate is a connection side connected to a side of another active matrix substrate, and the insulating film is a region along the edge of the pixel electrode layer adjacent to the connection side Thus, the active matrix layer is formed to be exposed.
[0029]
  According to the above configuration, a region where an insulating film is not formed in advance, that is, an “insulating film absent region” is provided along the edge of the pixel electrode layer close to the connection side. Therefore, contact between the insulating film and the side surface of the cutting means can be avoided by cutting the active matrix substrate after setting the cutting position in the insulating film absent region. As a result, the insulating film does not peel off from the active matrix layer at the time of cutting and can be prevented from floating up at the time of cutting.
[0030]
  Furthermore, since the insulating film is an organic film, not only can the active matrix layer and the pixel electrode layer be reliably insulated, but the insulating film is formed at a predetermined position on the active matrix layer. It becomes easy to do. Therefore, it is possible to accurately and reliably form the insulating film absent region, and it is possible to surely avoid the occurrence of the film floating defect and to reliably avoid the adverse effects due to chipping.
[0031]
  In the active matrix substrate according to the present invention, in addition to the above-described configuration, a portion between the connection side and the edge of the pixel electrode layer is a cut-off edge that is cut before connection. The edge of the insulating film is located between the cut edge that occurs after cutting the edge and the edge of the pixel electrode layer.
[0032]
  According to the above configuration, a cut line for cutting off the cut edge is set in the insulating film absent region formed along the edge of the pixel electrode layer. For this reason, when cutting the cut edge, it is possible to reliably avoid contact between the insulating film and the side surface of the cutting means, and thus it is possible to more reliably avoid the occurrence of defective film floating.
[0033]
  In the active matrix substrate according to the present invention, in addition to the above configuration, the distance between the cut edge and the edge of the pixel electrode layer is equal to or greater than the chipping width generated on the surface of the insulating substrate when the cut edge is cut off. It is characterized by being.
[0034]
  According to the above configuration, a certain margin is provided between the cutoff line and the edge of the pixel electrode layer. When the active matrix substrate is cut, chipping defects called chipping occur at the corners of the cut surface. However, by providing the margin on the edge side of the pixel electrode layer in the cut line, the chipping generation region is also insulated. A film will not be formed. As a result, adverse effects due to the occurrence of chipping can be avoided.
[0035]
  In the composite active matrix substrate according to the present invention, the distance between the cut edge and the edge of the pixel electrode layer is preferably in the range of 10 to 30 μm in the lower limit and in the range of 50 to 300 μm in the upper limit.
[0036]
  In the composite active matrix substrate according to the present invention, the insulating film is preferably a photosensitive resin composition capable of photolithography.
[0037]
  A composite active matrix substrate according to the present invention is formed by using a plurality of active matrix substrates having the above-described configuration, cutting each cut edge and then connecting the cut edges.
[0038]
  According to the above configuration, even when a composite active matrix substrate is formed using an active matrix substrate having an insulating film between the active matrix layer and the pixel electrode layer, the occurrence of film floating defects can be avoided and chipping can be prevented. Adverse effects can also be avoided. Therefore, the interval between the connection portions of the active matrix substrates can be adjusted to the pixel pitch, and a large active matrix substrate in which the connection portions are not conspicuous can be obtained.
[0039]
  In particular, since a film floating defect does not occur, a situation in which the film floating of the insulating film spreads over time does not occur at the connection site, and the reliability of the active matrix substrate can be improved.
[0040]
  Further, since it is not necessary to change the type of the insulating film or repair the defective film floating, it is possible to avoid complication of the manufacturing process and suppress an increase in manufacturing cost.
[0041]
  A display device according to the present invention is characterized by using the composite active matrix substrate having the above structure.
[0042]
  In addition, a detection apparatus according to the present invention is characterized by using the composite active matrix substrate having the above-described configuration.
[0043]
  According to each of the above configurations, since a composite active matrix substrate having high reliability and low manufacturing cost is used, a display device or a detection device having a larger area, higher definition, and higher reliability than conventional ones. Can be obtained inexpensively.
[0044]
DETAILED DESCRIPTION OF THE INVENTION
  [Embodiment 1]
  The first embodiment of the present invention will be described below with reference to FIGS. Note that the present invention is not limited to this.
[0045]
  The active matrix substrate according to the present invention is suitably used for a composite active matrix substrate in which a plurality of active matrix substrates are connected to each other at their ends, and a connection side connected to a side of another active matrix substrate. An insulating film is formed so as to expose the active matrix layer in a region along the edge of the pixel electrode layer adjacent to the pixel electrode layer. In other words, an insulating film absent region is provided along the edge of the pixel electrode layer close to the connection side.
[0046]
  In the following description, for convenience, the composite active matrix substrate is appropriately referred to as “composite substrate”, and individual active matrix substrates constituting the composite substrate are appropriately referred to as “unit substrates”.
[0047]
  As an example of the active matrix substrate according to the present invention, a composite substrate 51 formed of a unit substrate 52 and a unit substrate 53 can be cited as shown in FIG. In FIG. 2, for convenience of explanation, members that are not directly related to the explanation of the feature points of the present invention are omitted. Therefore, the active matrix substrate according to the present invention may include members not shown in FIG.
[0048]
  The unit substrates 52 and 53 have basically the same configuration, and include an insulating substrate 54, an active matrix layer (not shown) formed on the surface of the insulating substrate 54, and the active matrix. An insulating film 56 formed on the layer, and a pixel electrode layer 57 formed on the insulating film 56 and including a plurality of pixel electrodes 57a arranged in a matrix. That is, the active matrix substrate according to the present invention has a Pixel on Passivation structure (hereinafter abbreviated as a POP structure for convenience of description) having an insulating film 56 between the active matrix layer and the pixel electrode layer 57.
[0049]
  The insulating substrate 54 is not particularly limited as long as it has sufficient strength and insulating properties to serve as a base for the unit substrates 52 and 53. A substrate or the like can be suitably used. The thickness of the insulating substrate 54 is not particularly limited, but generally it is preferably in the range of 0.5 mm to 1 mm.
[0050]
  The active matrix layer includes switching elements and electrical wirings arranged in a matrix. As the switching element, for example, a TFT (Thin Film Transistor) element or the like is preferably used, but is not particularly limited. The shape and material of the electrical wiring is not particularly limited as long as it is a wiring formed in a lattice shape. For example, a wiring made of a metal thin film such as Al or Ta can be preferably used.
[0051]
  More specifically, for example, the electrical wiring is formed by crossing a scanning line (gate wiring) and a signal line (source wiring), and a TFT element is provided as a switching element in the vicinity of each wiring intersection. A configuration can be mentioned. The individual regions partitioned by the electric wiring (scanning lines / signal lines) formed in a matrix form pixels, and the pixel electrodes 57a are formed and arranged on the insulating film 56 so as to correspond to the respective pixels. Will be.
[0052]
  The specific configuration of the TFT element will be described. For example, when a bottom gate type TFT element is used, a gate insulating film made of an inorganic insulating film such as SiNx is formed on the gate electrode which is a part of the scanning line. Then, a semiconductor channel layer made of Si is formed, and a TFT element is formed by the source electrode and the drain electrode which are part of the signal line.
[0053]
  The insulating film 56 may be laminated on the active matrix layer so as to cover at least the entire surface of the active matrix layer. In the present invention, in particular, the connection connected to the side of another active matrix substrate is used. An insulating film 56 is formed so as to expose the active matrix layer in a region along the edge of the pixel electrode layer 57 adjacent to the side. A specific formation state of the insulating film 56 will be described later.
[0054]
  The insulating film 56 is not particularly limited as long as it is formed of a material that can insulate between the lower active matrix layer and the upper pixel electrode layer 57. More preferably, it is an organic film. Specifically, an acrylic resin, a polyimide resin, or the like can be preferably used as the organic polymer. Furthermore, by providing photosensitivity, the insulating film 56 can be formed by photolithography. Therefore, if an organic film is used as the insulating film 56, not only can the active matrix layer and the pixel electrode layer 57 be reliably insulated, but the insulating film 56 is formed on the active matrix layer as described later. It becomes easy to form at a predetermined position.
[0055]
  The thickness of the insulating film 56 is not particularly limited, and may be a thickness that can sufficiently insulate the active matrix layer and the pixel electrode layer 57 depending on the material, but may be an acrylic resin or a polyimide resin. In the case of an organic film, it is preferably in the range of 2 μm to 4 μm.
[0056]
  Although not shown in FIG. 2, through holes are formed in the insulating film 56 for each pixel of the active matrix layer (see FIG. 1A). This through hole allows electrical contact between the pixel electrode 57a and the electrode of the switching element (for example, the drain electrode of the TFT element).
[0057]
  A method for forming the insulating film 56 including the through hole and the insulating film absent region described later is not particularly limited, but generally a photolithography processing method is preferably used. If the photolithographic processing method is used, the resin composition to be the insulating film 56 is made photosensitive, and a fine shape can be easily formed by simply performing exposure and development processing using a mask corresponding to a through hole or an insulating film absent region. And it can form reliably.
[0058]
  As described above, a plurality of the pixel electrodes 57a are provided on the insulating film 56 so as to correspond to a plurality of pixels of the active matrix layer, thereby forming one layer (pixel electrode layer 57). The pixel electrode 57a can be used to display image data and detect electromagnetic waves. The material of the pixel electrode 57a is not particularly limited as long as it is an appropriate material according to the use of the active matrix substrate. Generally, a transparent conductive film such as ITO (Indium Tin Oxide) is used. Alternatively, a metal thin film such as Al is used. The transparent conductive film is suitable for a transmissive display device, and the metal thin film is suitable for a reflective display device, but is not particularly limited.
[0059]
  As described above, the unit substrates 52 and 53 according to the present invention are formed so that the insulating film 56 exposes the active matrix layer in the region along the edge of the pixel electrode layer 57 close to the connection side. . That is, an “insulating film absent region”, which is a region where the insulating film 56 is not formed, is provided in advance along the edge of the pixel electrode layer 57 close to the connection side.
[0060]
  Therefore, if the unit substrate 52 or 53 is cut after setting the cutting position in the insulating film absence region, the contact between the insulating film 56 and the side surface of the cutting means can be avoided. As a result, the insulating film 56 does not peel off from the active matrix layer at the time of cutting and can be prevented from floating up at the time of cutting.
[0061]
  Specifically, as shown in FIG. 3A, for example, in the case of the unit substrate 52, the region where the pixel electrode layer 57 is formed is a pixel region 58, and the right side of the unit substrate 52 on the right side in the drawing. Assuming that the side is the connection side 52a, a portion between the edge 58a adjacent to the connection side 52a of the pixel region 58 and the connection side 52a is a cut-off edge 52b that is cut before connection.
[0062]
  When cutting the cut edge 52b, a cut line 52c indicated by a one-point difference line in the figure is set at a position as close as possible to the edge 58a, but at least in the vicinity of the cut line 52c, An insulating film absence region 59 in which the insulating film 56 is not formed is provided so as to be surrounded by a dotted line in the drawing. In other words, the cut line 52c is set at a position where the insulating film absence region 59 is to be formed. Then, for example, as shown in FIG. 3B, a cutting edge 52b is cut along the cutting line 52c using a dicing blade 60 as cutting means.
[0063]
  The shape of the insulating film absent region 59, that is, the shape of the region exposing the active matrix layer along the edge 58a is not particularly limited. For example, as shown in FIG. 3A, it may have a slit shape along the edge 58a, or the entire cut edge 52b may be the insulating film absence region 59. That is, if the active matrix layer is exposed so that the cut line 52c can be sufficiently formed along the edge 58a, the shape of the insulating film absent region 59, that is, the shape of the insulating film 56 to be formed is particularly It is not limited.
[0064]
  The cutting means is not particularly limited as long as it can cut the insulating substrate 54. In general, a dicing blade 60 is preferably used. As the dicing blade 60, a conventionally known configuration can be suitably used. Specifically, the dicing blade 60 may be a diamond blade with an abrasive grain size of # 500 and a bonding material of resin, and the dicing conditions include a blade rotation speed of 30000 rpm and a workpiece feed speed of A condition of 2 mm / sec can be mentioned.
[0065]
  Here, the above-described cutting process will be described in more detail with reference to FIGS.
[0066]
  As shown in FIG. 1A, in the unit substrate 52, an active matrix layer 61 is formed on an insulating substrate 54, an insulating film 56 is laminated thereon, and a plurality of pixel electrodes 57a are further formed thereon. The pixel electrode layer 57 is formed by being disposed. In the insulating film 56, the above-described through hole 63 is formed, and the TFT element 62 and the pixel electrode 57a included in the active matrix layer 61 are electrically connected through the through hole 63. ing.
[0067]
  In FIG. 1A, an insulating film absence region 59 is formed on the right side in the drawing, and a cutting line 52c (see FIG. 3A) is set here to cut the cutting edge 52b. Here, if the side surface 60a of the dicing blade 60 contacts the edge 56a of the insulating film 56 at the time of cutting, the insulating film 56 is lifted from the active matrix layer 61 by being dragged by the side surface 60a of the rotating dicing blade 60 ( (See FIG. 9B). However, in the present invention, since the insulating film absence region 59 is formed, the side surface 60a of the dicing blade 60 is prevented from coming into contact with the edge 56a of the insulating film 56.
[0068]
  Therefore, it is possible to prevent a film floating defect from occurring at the edge 56a of the insulating film 56, and to avoid adversely affecting the pixel electrode 57a adjacent to the cut side 52a (see FIG. 3A). .
[0069]
  Here, in the present invention, in order to surely avoid the influence associated with the cutting processing of the cut edge portion 52a including the occurrence of the above-mentioned film floating failure, the following regulation of the interval is very important.
[0070]
  First, since the dicing blade 60 has a constant thickness D, it is very preferable that the width C of the insulating film absent region 59 is larger than the thickness D (C> D). If the width C is smaller than the thickness D, the side surface 60a of the dicing blade 60 is liable to come into contact with the edge 56a of the insulating film 56, which is not preferable. Of course, the width of the cutting line 52c (see FIG. 3A) set before cutting must also take into account the thickness of the dicing blade 60.
[0071]
  Further, an insulating film 56 is formed between the cut edge 66 shown in FIGS. 1A and 1B and the edge 58a of the pixel region 58, which is generated after cutting the cut edge 52b along the cut line 52c. It is highly preferred that the edge 56a is located. 1A and 1B, the edge 58a of the pixel region 58 is formed by the edge of the pixel electrode 57a facing the insulating film absent region 59. Therefore, in the following description, the edge 58a of the pixel electrode layer 57 is expressed.
[0072]
  As a result, the cutoff line 52c is reliably set in the insulating film absent region 59 formed along the edge 58a of the pixel electrode layer 57. Therefore, when the cut edge portion 52b is cut, the contact between the insulating film 56 and the side surface 60a of the dicing blade 60 can be reliably avoided, so that the occurrence of defective film floating can be more reliably avoided. it can.
[0073]
  Next, in order to suppress the influence of the chipping 68 that occurs during the cutting process, the interval A between the cutting edge 66 and the edge 58a of the pixel electrode layer 57 is formed on the surface of the insulating substrate 54 when the cutting edge part 52a is cut. It is highly preferred that it be greater than the width of the resulting chipping 68.
[0074]
  When the unit substrate 52 is cut by the dicing blade 60 without being limited to the POP structure, chipping that is a fine chip defect is present in the entire cutting edge 66 of the unit substrate 52 as shown in FIGS. 68 (also called burrs or peels) occurs.
[0075]
  The chipping 68 occurs when the abrasive grains contained in the dicing blade 60 collide with the cutting edge 66 of the unit substrate 52. Therefore, the chipping 68 is performed at the time of cutting the unit substrate 52 regardless of the POP structure. It is a defect that always occurs. However, by optimizing the grain size of the abrasive grains and the cutting conditions, the width of the chipping 68 (referred to as the generation region width B) can be controlled within a range of 10 to 30 μm.
[0076]
  Therefore, in the present invention, as described above, the interval A, which is a certain margin, is provided between the cutting edge 66 and the edge 58a of the pixel electrode layer 57. If the distance A is larger than the generation region width B (A> B), the insulating film 56 is not formed in the generation region of the chipping 68.
[0077]
  If the chipping 68 occurs, at least the active matrix layer 61 on the surface (or the surface of the insulating substrate 54 depending on the situation) is lost. For this reason, the chipping 68 may cause a gap between the insulating substrate 54 and the insulating film 56, which may cause a film floating defect.
[0078]
  However, if the insulating film 56 is not formed in the region where the chipping 68 is generated, adverse effects due to the generation of the chipping 68 can be avoided. Therefore, in the present invention, it is preferable that the distance A between the cutting edge 66 and the edge 58a of the pixel electrode layer 57 is larger than the region B where the chipping 68 occurs.
[0079]
  In addition, as a concrete numerical value of the said space | interval A, the lower limit should just become it in the said range of 10-30 micrometers, and is not limited as a exact | strict numerical value. On the other hand, the upper limit of the interval A is appropriately set according to the pixel pitch E shown in FIG. 1A, that is, the pitch of the pixel electrodes 57a formed on the unit substrate 52 (53). Although not limited, practically, the range of 50 to 300 μm is preferable.
[0080]
  In this way, if the above-described size regulation is performed on the insulating film absent region 59, which is the position where the cut edge 52b is cut, the occurrence of film floating unnecessary and the influence of the chipping 68 can be reliably avoided. In particular, in the present invention, since the insulating film 56 is formed using a photosensitive resin composition capable of photolithography, the active matrix layer 61 and the pixel electrode layer 57 can be reliably insulated. In addition, the insulating film 56 can be easily formed at a predetermined position on the active matrix layer 61. Therefore, the insulating film absent region 59 can be formed accurately and reliably, the occurrence of the film floating failure can be surely avoided, and the adverse effect due to the chipping 68 can be avoided reliably.
[0081]
  Thereafter, the unit substrates 52 and 53 from which the cut edge portion 52b has been cut are connected with the cut sides 66 facing each other as shown in FIG. 4, whereby the composite substrate 51 according to the present invention as shown in FIG. Can be formed.
[0082]
  Here, when the connection sides 66 of the unit substrates 52 and 53 are connected to each other, as shown in FIG. 4, the interval F between the connection portions of the substrates, that is, the pixel pitch F of the connection portion is set to the other portion. It is very preferable that the interval be equal to or close to the pixel pitch E (see also FIG. 1A). As a result, when the entire composite substrate 51 is viewed, the pixel pitch E becomes substantially constant, so that the connection portion does not stand out, and a high-quality composite substrate 51 as shown in FIG. 2 can be obtained.
[0083]
  Conventionally, when a composite substrate is formed using a plurality of active matrix substrates having a POP structure, ideally, the unit substrates 202 and 203 constituting the composite substrate 201 are formed as shown in an enlarged portion surrounded by a circle in FIG. An insulating film 56 is also formed at the connection portion. The basic configuration of the unit substrates 202 and 203 is the same as that of the unit substrates 52 and 53 according to the present invention, and a detailed description thereof will be omitted.
[0084]
  On the other hand, in the composite substrate 51 according to the present invention, the insulating film 56 is intentionally removed in the vicinity of the connection portions of the unit substrates 52 and 53 as shown in the enlarged portion surrounded by a circle in FIG. It has become.
[0085]
  As described above, in the present invention, when a composite substrate is formed using a plurality of active matrix substrates having a POP structure, an insulating film is not formed at a position to be a connection portion (near a connection side) in each unit substrate. For this reason, in the manufacturing process of the composite substrate, the occurrence of defective film floating can be avoided and the adverse effect of chipping can be avoided. Therefore, the interval between the connection portions of the active matrix substrates can be adjusted to the pixel pitch, and a large active matrix substrate in which the connection portions are not conspicuous can be obtained.
[0086]
  In particular, since a film floating defect does not occur, a situation in which the film floating of the insulating film spreads over time does not occur at the connection site, and the reliability of the active matrix substrate can be improved.
[0087]
  Further, since it is not necessary to change the type of the insulating film or repair the defective film floating, it is possible to avoid complication of the manufacturing process and suppress an increase in manufacturing cost.
[0088]
  In addition, once a manufacturing facility for manufacturing an active matrix substrate is constructed, an active matrix substrate larger than the size suitable for the manufacturing facility cannot be manufactured. It was virtually impossible to manufacture with existing manufacturing equipment. However, in the present invention, since a composite substrate having a high-quality and high-reliability POP structure can be reliably manufactured, an increase in the manufacturing cost of an active matrix substrate with a large area can be achieved without making a large capital investment. Can be avoided.
[0089]
  [Embodiment 2]
  The following describes the second embodiment of the present invention with reference to FIG. Note that the present invention is not limited to this. Further, members having the same functions as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0090]
  In this embodiment, an example in which the composite active matrix substrate obtained in Embodiment 1 is applied to a detection device will be described.
[0091]
  The detection device is a device that detects two-dimensional information of electromagnetic waves (radiation, visible light, infrared light, etc.) and two-dimensional distribution information of a surface shape. For example, an X-ray image is directly converted into an electrical signal without a film. X-ray flat panel detectors that read out as are known. Therefore, in the present embodiment, an X-ray flat panel detector will be described as an example of the detection device.
[0092]
  As shown in FIG. 5, the X-ray flat detector 10 according to the present embodiment includes a detection substrate 11, a photoelectric conversion layer (conversion layer: conversion means) 41 that converts electromagnetic waves such as X-rays into electric charges, and generation. The bias generated by the bias application (bias application electrode layer) 42 for moving the generated charge toward the detection substrate 11, the high-voltage power supply 43 for the bias electrode 42, and the charge generated by the photoelectric conversion layer 41 are read from the detection substrate 11. And a charge detection unit 44.
[0093]
  The detection substrate (signal readout array) 11 is formed with the back side of the composite substrate 51 (configuration in which a plurality of unit substrates 52 and 53 are connected by cutting edges) in the first embodiment, that is, the pixel electrode layer 57. The support substrate 12 is bonded to the surface opposite to the side. That is, the detection substrate 11 has basically the same configuration as the composite substrate 51, but the support substrate 12 is bonded to the back side in order to improve the substrate strength.
[0094]
  The photoelectric conversion layer 41 is formed so as to substantially cover the entire pixel electrode layer 57 formed on the surfaces of the unit substrates 52 and 53, and receives electromagnetic waves and converts them into electric charges. . The photoelectric conversion layer 41 is not particularly limited as long as it is a photoelectric conversion film that can convert electromagnetic waves into electric charges, and is set according to the type of electromagnetic waves to be irradiated. Various semiconductor films are used for the.
[0095]
  In the present embodiment, since the irradiated electromagnetic waves are X-rays, 0.5 mm to 1 are considered in consideration of sensitivity to X-rays and ease of film formation on the detection substrate 11 having a large area. A-Se (amorphous selenium) having a thickness of 0.5 mm can be preferably used.
[0096]
  The bias electrode 42 is stacked on the photoelectric conversion layer 41 so as to substantially cover the entire surface of the photoelectric conversion layer 41, and applies a bias to the photoelectric conversion layer 41. The bias electrode 42 is not particularly limited as long as it can apply a bias to the photoelectric conversion layer 41. For example, a thin film such as Au or Al is used.
[0097]
  The high voltage power source 43 is not particularly limited as long as it can supply a high voltage potential to the photoelectric conversion layer 41, and various conventionally known high voltage power sources can be used. The charge detection unit 44 sequentially reads out the charges generated in the photoelectric conversion layer 41 through the detection substrate 11 and acquires a two-dimensional X-ray image as charge distribution information. The specific configuration of the charge detection unit 44 is not particularly limited, and a conventionally known configuration can be suitably used.
[0098]
  A specific detection operation of the X-ray flat panel detector 10 according to the present embodiment will be described.
[0099]
  First, when the photoelectric conversion layer 41 is irradiated with X-rays, electric charges composed of electron-hole pairs are generated in the photoelectric conversion layer 41. The generated charges (charges and holes) move to the bias electrode 42 side and the detection substrate 11 side in accordance with the polarity of the bias applied to the photoelectric conversion layer 41. The charges drawn toward the detection substrate 11 are accumulated in a storage capacitor provided in each pixel on the surface of the detection substrate 11. The accumulated charges are sequentially read out using an active element (for example, a TFT element), and the charge detection unit 44 acquires a two-dimensional X-ray image as charge distribution information.
[0100]
  The X-ray flat panel detector is mainly used for medical X-ray imaging. In this case, it is necessary to image a relatively large area such as a human breast, and it is required to have a corresponding imaging region. Therefore, an active matrix substrate suitable for an X-ray flat panel detector is preferably one having a large area with a POP structure. However, it has been difficult to obtain an active matrix substrate having a large area and high quality and high reliability at a low cost.
[0101]
  On the other hand, as shown in this embodiment, if a composite substrate is formed by using a plurality of small-sized unit substrates, an inexpensive X-ray flat detector can be provided even with a large area. In addition, in the present invention, since an insulating film is not formed at the connecting portion of each unit substrate, it is possible to avoid the occurrence of defective film floating, and the active matrix substrate can be manufactured with high quality and high quality without increasing the manufacturing cost. It can be reliable.
[0102]
  The X-ray flat panel detector having the above configuration is a direct conversion type that converts X-rays directly into electric charges. However, the detection device according to the present invention is not limited to this, for example, an indirect conversion type. Also good.
[0103]
  Specifically, as an indirect conversion type flat panel detector, for example, each pixel of the composite substrate 11 includes an active element (TFT) that performs switching, and a photoelectric conversion element (photodiode or Phototransistor: a photoelectric conversion panel in which both conversion means are formed and the photoelectric conversion panel provided on the photoelectric conversion panel (that is, on the surface side of a plurality of unit substrates) to convert electromagnetic waves such as X-rays into light (particularly visible light) The structure which comprises the scintillator to convert can be mentioned.
[0104]
  In the indirect conversion type flat detector having the above configuration, the irradiated electromagnetic wave is converted into light by the scintillator, and then the light is converted into electric charge by the photoelectric conversion element. The type of electromagnetic wave applied to the indirect conversion type flat detector is not particularly limited, but usually includes electromagnetic waves excluding light, particularly X-ray radiation.
[0105]
  As described above, since the unit substrate and the composite substrate according to the present invention have high reliability and are not high in manufacturing cost, a detection device having a large area, high definition, and high reliability can be obtained at a lower cost than before. be able to.
[0106]
  [Embodiment 3]
  The following describes the third embodiment of the present invention with reference to FIG. Note that the present invention is not limited to this. Further, members having the same functions as those described in the first or second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0107]
  In this embodiment, an example in which the composite active matrix substrate obtained in Embodiment 1 is applied to a display device will be described.
[0108]
  Examples of the display device include a liquid crystal display device (LCD). In recent years, the demand for LCDs as monitors for AV devices and OA devices has been rapidly increasing, and application to wall-mounted TVs is also expected. Further, as other flat display devices, organic EL display devices and the like are known, and this organic EL display device is also expected to have a larger screen in the future. Therefore, in this embodiment, a liquid crystal panel used for an LCD will be described as an example of the display device.
[0109]
  As shown in FIG. 6, the liquid crystal panel 32 according to the present embodiment is a transmissive type, the composite substrate 51 of the first embodiment, and the counter substrate 29 bonded to the composite substrate 51, And a polarizing plate 26 and a deflecting plate 30 on the outer surfaces of the composite substrate 51 and the counter substrate 29 (on the opposite side to the surfaces facing each other), respectively. Are pasted together.
[0110]
  The composite substrate 51 is the same as that described in the first embodiment. However, in order to improve the substrate strength, the back side, that is, the side on which the pixel electrode 57a (pixel electrode layer) is formed. The support substrate 20 is bonded to the opposite side.
[0111]
  On the opposing surface of the composite substrate 51, a plurality of pixel electrodes 57a are provided in a matrix on substantially the entire surface, forming a pixel electrode layer. A counter substrate 29 is bonded to the side on which the pixel electrode layer is formed by a sealing material 31. Since the region where the pixel electrode layer is formed is an image display region of the liquid crystal panel 32, the sealing material 31 is formed in a linear shape so as to surround the image display region. Then, a liquid crystal layer 25 is formed by sealing liquid crystal as an electro-optic medium in a flat space sealed between these substrates by a sealing material 31.
[0112]
  As a specific material or the like of the composite substrate 51, a material suitable for the display device as described in the first embodiment is used. As the liquid crystal layer 25 and the sealing material 31, conventionally known materials can be suitably used.
[0113]
  As the counter substrate 29, a glass substrate similar to that used for the composite substrate 51 is preferably used. In addition, red, green, and blue (R, G, and B) color filters 28 are formed on the opposing surface of the opposing substrate 29, and a flat common electrode 27 is stacked thereon. As the color filter 28 and the common electrode 27, conventionally known ones are preferably used. As the deflection plates 26 and 30, conventionally known ones are preferably used.
[0114]
  A backlight (not shown) is provided on the back side of the composite substrate 51. Light (backlight) is emitted from the backlight to the liquid crystal panel 32, passes through the liquid crystal layer 25, and is emitted from the back side of the counter substrate 29. Therefore, the back side of the counter substrate 29 is the display surface of the liquid crystal panel 32.
[0115]
  Next, the driving principle and display operation of the liquid crystal panel 32 will be described.
[0116]
  In the plurality of pixels provided on the composite substrate 51, the gate electrodes of the TFT elements are sequentially scanned and driven. As a result, a voltage corresponding to the display signal is applied to the pixel electrode 57a through the TFT element and the signal electrode (not shown). Since the common electrode 27 is opposed to all the pixel electrodes 57a, a voltage corresponding to the display signal is applied to the liquid crystal layer 25 interposed therebetween. Here, when the backlight light enters the liquid crystal layer 25, the light is modulated by the electro-optical characteristics of the liquid crystal, and an image is displayed.
[0117]
  LCDs using the above-mentioned liquid crystal panels are mainly used for AV and OA, but in recent years, in particular, for AV and the like, a relatively wide display area is required to display an image with improved realism. And a high-definition pixel pitch are demanded. Therefore, an active matrix substrate suitable for a liquid crystal panel is preferably one having a large area with a POP structure. However, it has been difficult to obtain an active matrix substrate having a large area and high quality and high reliability at a low cost.
[0118]
  On the other hand, as shown in this embodiment, when a composite substrate is formed using a plurality of small-sized unit substrates, an inexpensive liquid crystal panel can be provided even in a large area. In addition, in the present invention, since an insulating film is not formed at the connecting portion of each unit substrate, it is possible to avoid the occurrence of defective film floating, and the active matrix substrate can be manufactured with high quality and high quality without increasing the manufacturing cost. It can be reliable.
[0119]
  The liquid crystal panel having the above configuration is a transmission type that displays an image by transmitting light from the back to the display surface. However, the display device according to the present invention is not limited to this, and is a reflection type. There may be.
[0120]
  Specifically, for example, the pixel electrode may be a reflective display device using a reflective type (for example, a metal pixel electrode) instead of a transmissive type such as ITO. The liquid crystal panel uses a polarizing plate, but may be a transmissive display device that does not use a deflecting plate. For example, a display device adopting a method such as a guest / host display method or a light scattering (dispersion) display method can be given.
[0121]
  Furthermore, the display device according to the present invention is not limited to one using liquid crystal. For example, a display device using an organic EL (electroluminescence) material, an electrophoretic material, an electrochromic material, or the like as an electro-optic medium other than liquid crystal may be used.
[0122]
  As described above, since the unit substrate and the composite substrate according to the present invention have high reliability and are not high in manufacturing cost, a display device having a large area, high definition, and high reliability can be obtained at a lower cost than before. be able to.
[0123]
  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and technical means disclosed in different embodiments are appropriately combined. Needless to say, embodiments obtained in this manner are also included in the technical scope of the present invention.
[0124]
【The invention's effect】
  As described above, the active matrix substrate according to the present invention is formed on the surface of the insulating substrate and includes the active matrix layer including the switching elements and the electrical wirings arranged in a matrix, and is formed on the active matrix layer. In an active matrix substrate including an insulating film and a pixel electrode layer formed on the insulating film and including a plurality of pixel electrodes arranged in a matrix,The insulating film is an organic film mainly composed of an organic polymer,At least one side of the periphery of the active matrix substrate is a connection side connected to a side of another active matrix substrate, and the insulating film is a region along the edge of the pixel electrode layer adjacent to the connection side Thus, the active matrix layer is formed to be exposed.
[0125]
  Therefore, in the above configuration, the insulating film absent region is provided along the edge of the pixel electrode layer close to the connection side. If the matrix substrate is cut, contact between the insulating film and the side surface of the cutting means can be avoided. As a result, the insulating film is not peeled off from the active matrix layer at the time of cutting and has the effect of avoiding film floating defects at the time of cutting.
[0126]
  Furthermore, since the insulating film is an organic film, it is possible to accurately and reliably form the insulating film absent region, and it is possible to surely avoid the occurrence of the film floating defect and to reliably prevent adverse effects due to chipping. There is an effect that it can be avoided.
[0127]
  In the active matrix substrate according to the present invention, in addition to the above-described configuration, a portion between the connection side and the edge of the pixel electrode layer is a cut-off edge that is cut before connection. In this configuration, the edge of the insulating film is located between the cut edge generated after cutting the edge portion and the edge of the pixel electrode layer.
[0128]
  Therefore, in the above configuration, a cut line for cutting the cut edge is set in the insulating film absent region. For this reason, when cutting the cut edge, it is possible to reliably avoid contact between the insulating film and the side surface of the cutting means, so that the effect of preventing the occurrence of defective film floating can be avoided more reliably. Play.
[0129]
  In the active matrix substrate according to the present invention, in addition to the above configuration, the distance between the cut edge and the edge of the pixel electrode layer is equal to or greater than the chipping width generated on the surface of the insulating substrate when the cut edge is cut off. It is the composition which is.
[0130]
  Therefore, in the above configuration, a certain margin is provided between the cutoff line and the edge of the pixel electrode layer. Therefore, an insulating film is not formed also in the above chipping generation region. As a result, it is possible to avoid an adverse effect due to the occurrence of chipping.
[0131]
  The composite active matrix substrate according to the present invention is formed by using a plurality of active matrix substrates having the above-described configuration, cutting each cut edge and then connecting the cut edges.
[0132]
  Therefore, in the above configuration, even when the composite active matrix substrate is formed, the occurrence of defective film floating can be avoided and the adverse effect of chipping can be avoided. For this reason, the interval between the connection portions of the active matrix substrates can be adjusted to the pixel pitch, and it is possible to obtain a large-sized active matrix substrate in which the connection portions are not conspicuous.
[0133]
  In particular, since the film floating defect does not occur, the situation that the film floating of the insulating film spreads over time does not occur at the connection portion, and the reliability of the active matrix substrate can be improved. Play.
[0134]
  In addition, since it is not necessary to change the type of insulating film or to repair defective film floating, it is possible to avoid complication of the manufacturing process and to suppress an increase in manufacturing cost. Play together.
[0135]
  The display device according to the present invention has a configuration using the composite active matrix substrate having the above configuration.
[0136]
  Further, the detection apparatus according to the present invention has a configuration using the composite active matrix substrate having the above configuration.
[0137]
  Therefore, in each of the above structures, a composite active matrix substrate that has high reliability and is not expensive to manufacture is used. Therefore, a display device or a detection device that has a larger area, higher definition, and higher reliability than conventional ones. Can be obtained at low cost.
[Brief description of the drawings]
FIG. 1A is a cross-sectional view showing a state where a cut edge of an active matrix substrate according to an embodiment of the present invention is cut by a dicing blade, and FIG. 1B is a plan view. .
2 is a cross-sectional view showing a configuration of a composite active matrix substrate using the active matrix substrate shown in FIGS. 1 (a) and 1 (b). FIG.
3A is a plan view for explaining the positional relationship between a cut edge, a cut line, and an insulating film absent region in the active matrix substrate shown in FIGS. 1A and 1B; FIG. It is a perspective view which shows the state which has cut | disconnected the cutting edge part with the dicing blade.
4 is a plan view for explaining the relationship between the interval between connecting portions of unit substrates and the pixel pitch when forming the composite active matrix substrate shown in FIG. 2; FIG.
FIG. 5 is a cross-sectional view showing a schematic configuration of a detection apparatus according to another embodiment of the present invention, using the composite active matrix substrate shown in FIG. 2;
6 is a cross-sectional view showing a schematic configuration of a display device according to another embodiment of the present invention, using the composite active matrix substrate shown in FIG.
7A to 7C are process diagrams showing a schematic configuration of a conventional composite active matrix substrate.
FIGS. 8A to 8G are process diagrams showing manufacturing processes of another conventional composite active matrix substrate. FIGS.
9A is a cross-sectional view showing a state where an edge portion of a conventional active matrix substrate is cut by a dicing blade, and FIG. 9B is a plan view.
FIG. 10 is a cross-sectional view showing a configuration of a conventional ideal composite active matrix substrate.
[Explanation of symbols]
10 X-ray flat panel detector (detection device)
32 Liquid crystal panel (display device)
51 Composite substrate (Composite active matrix substrate)
52 Unit substrate (active matrix substrate)
52a Connection side
52b Cut edge
53 Unit substrate (active matrix substrate)
54 Insulating substrate
56 Insulating film
56a Edge of insulating film
57 Pixel electrode layer
57a Pixel electrode
58a Edge of pixel area (edge of pixel electrode layer)
59 Insulating film absence region
61 Active matrix layer
62 TFT element (switching element)
66 Cutting edge
68 Chipping

Claims (8)

An active matrix layer formed on the surface of an insulating substrate and including switching elements and electric wirings arranged in a matrix, an insulating film formed on the active matrix layer, and formed on the insulating film in a matrix In an active matrix substrate comprising a pixel electrode layer composed of a plurality of pixel electrodes arranged in
The insulating film is an organic film mainly composed of an organic polymer,
At least one side of the periphery of the active matrix substrate is a connection side connected to a side of another active matrix substrate,
The active matrix substrate, wherein the insulating film is formed so as to expose the active matrix layer in a region along an edge of the pixel electrode layer adjacent to the connection side. In addition, the portion between the connection side and the edge of the pixel electrode layer is a cut edge that is cut before connection,
2. The active matrix substrate according to claim 1, wherein an edge of the insulating film is located between a cut edge generated after cutting the cut edge and an edge of the pixel electrode layer. 3. The active matrix according to claim 2 , wherein the distance between the cut edge and the edge of the pixel electrode layer is equal to or greater than the width of chipping generated on the surface of the insulating substrate when the cut edge is cut off. substrate. 4. The active matrix substrate according to claim 2, wherein a distance between the cut side and an edge of the pixel electrode layer is within a range of 10 to 30 μm at a lower limit and 50 to 300 μm at an upper limit. . 5. The active matrix substrate according to claim 1, wherein the insulating film is a photosensitive resin composition capable of photolithography. A plurality of the active matrix substrates according to any one of claims 1 to 5, wherein a plurality of active matrix substrates are cut out from each connection side, and then the cut sides are connected to each other. Composite active matrix substrate. A display device comprising the composite active matrix substrate according to claim 6 . A detection apparatus comprising the composite active matrix substrate according to claim 6 .

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