WO2019064729A1

WO2019064729A1 - Display device

Info

Publication number: WO2019064729A1
Application number: PCT/JP2018/023126
Authority: WO
Inventors: 丸山　哲
Original assignee: 株式会社ジャパンディスプレイ
Priority date: 2017-09-26
Filing date: 2018-06-18
Publication date: 2019-04-04
Also published as: JP2019061007A

Abstract

This display device has: a base member having a first surface and a second surface on the reverse side of the first surface; a first region that includes a display section disposed on the first surface of the base member; a second region including wiring disposed on the first surface of the base member; a third region that includes a terminal section disposed on the first surface of the base member, and a drive circuit that outputs a data signal to the display section; and an insulating layer disposed across the first region and the second region, said insulating layer being on the first surface of the base member. The insulating layer has a through groove in the second region, said throughh groove being disposed along the display section, and having a bottom surface from which the base member is exposed, and side wall surfaces that include a plurality of steps. The wiring is disposed to intersect the through groove.

Description

Display device

One embodiment of the present invention relates to the structure of an interlayer insulating film and a wiring in a display device.

The display device has an area in which a display unit in which an image is displayed is arranged, and a peripheral area outside the display unit and in which an input terminal and a driver circuit are arranged. The peripheral area is also referred to as a frame area because it is arranged to surround the display portion. In a display device, it is required to narrow a frame area that does not directly contribute to the display of an image (this may be referred to as “narrowing of the frame”). As a technology for narrowing the frame of the display device, a display device in which a region corresponding to the frame region is bent to the back side of the display unit using a foldable substrate such as a plastic substrate is disclosed (for example, Patent Document 1) reference).

JP, 2011-209405, A

In the frame region of the display device, a wiring is provided in contact with the insulating layer or sandwiched by the insulating layer. When the display device is bent in the frame area, stress acting on the insulating layer and the wiring becomes a problem. For example, peeling of the insulating layer, cracking, disconnection of wiring, or the like caused by bending the substrate is a problem.

A display device according to an embodiment of the present invention includes a base member having a first surface and a second surface opposite to the first surface, and a first region including a display unit disposed on the first surface of the base member. And a second region including a wire disposed on the first surface of the base member, a terminal portion disposed on the first surface of the base member, and a drive circuit for outputting a data signal to the display portion. And an insulating layer disposed over the first area and the second area on the first surface of the base member, and the insulating layer is provided along the display portion in the second area. And a through groove having a bottom surface exposing the base member and a side wall surface including a plurality of steps, and the wiring is disposed to intersect the through groove.

It is a figure which shows arrangement | positioning of each site | part which comprises the display apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the outline of the laminated structure of the display apparatus which concerns on one Embodiment of this invention. It is a sectional view showing the state where the display concerning one embodiment of the present invention was bent. It is sectional drawing which shows the structure of the pixel of the display apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the structure of a part of 1st area | region, 2nd area | region, and 3rd area | region of the display apparatus which concerns on one Embodiment of this invention. It is a top view which shows the structure of the 2nd field of a display concerning one embodiment of the present invention. FIG. 7 is a view showing a structure of a second region of a display device according to an embodiment of the present invention, and is a cross-sectional view taken along line C1-C2. It is sectional drawing explaining the manufacturing method of the display apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the structure of the 2nd area | region of the display apparatus which concerns on one Embodiment of this invention. FIG. 14 is a diagram for explaining a manufacturing process of the display device according to the embodiment of the present invention, and showing a cross-sectional view of a pixel. It is a figure explaining the manufacturing process of the display apparatus which concerns on one Embodiment of this invention, and shows sectional drawing of a part of 1st area | region and 2nd area | region. FIG. 14 is a diagram for explaining a manufacturing process of the display device according to the embodiment of the present invention, and showing a cross-sectional view of a pixel. It is a figure explaining the manufacturing process of the display apparatus which concerns on one Embodiment of this invention, and shows sectional drawing of a part of 1st area | region and 2nd area | region. FIG. 14 is a diagram for explaining a manufacturing process of the display device according to the embodiment of the present invention, and showing a cross-sectional view of a pixel. It is a figure explaining the manufacturing process of the display apparatus which concerns on one Embodiment of this invention, and shows sectional drawing of a part of 1st area | region and 2nd area | region. FIG. 14 is a diagram for explaining a manufacturing process of the display device according to the embodiment of the present invention, and showing a cross-sectional view of a pixel. It is a figure explaining the manufacturing process of the display apparatus which concerns on one Embodiment of this invention, and shows sectional drawing of a part of 1st area | region and 2nd area | region. FIG. 14 is a diagram for explaining a manufacturing process of the display device according to the embodiment of the present invention, and showing a cross-sectional view of a pixel. It is a figure explaining the manufacturing process of the display apparatus which concerns on one Embodiment of this invention, and shows sectional drawing of a part of 1st area | region and 2nd area | region. FIG. 14 is a diagram for explaining a manufacturing process of the display device according to the embodiment of the present invention, and showing a cross-sectional view of a pixel. It is a figure explaining the manufacturing process of the display apparatus which concerns on one Embodiment of this invention, and shows sectional drawing of a part of 1st area | region and 2nd area | region. It is sectional drawing which shows the structure of the 2nd area | region of the display apparatus which concerns on one Embodiment of this invention. It is sectional drawing explaining the manufacturing method of the display apparatus which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in many different modes, and is not construed as being limited to the description of the embodiments exemplified below. Although the drawings may be schematically represented with respect to the width, thickness, shape, etc. of each portion in comparison with the actual embodiment in order to make the description clearer, this is merely an example, and the interpretation of the present invention is limited. It is not a thing. Further, in the specification and the drawings, the same elements as those described above with reference to the existing figures are denoted by the same reference numerals (or reference numerals with a, b, etc. added after numbers) for detailed explanation. It may be omitted as appropriate. Furthermore, the letters appended with “first” and “second” for each element are convenient indicators used to distinguish each element and have no further meaning unless specifically stated otherwise .

In this specification, when one member or area is "above (or below)" another member or area, it is immediately above (or just below) the other member or area unless there is a particular limitation. Not only in some cases, but also above (or below) other members or regions, that is, including other components interposed above (or below) other members or regions . In the following description, unless otherwise noted, in the cross-sectional view, the side on which the pixel region and the touch sensor are arranged with respect to one main surface of the substrate is described as “upper”.

First embodiment:
FIG. 1 shows the arrangement of each part constituting a display device 100 according to an embodiment of the present invention. The display device 100 includes a base member 102 having a first surface and a second surface opposite to the first surface. The first surface of the base member 102 includes a display area 112 in which the pixels 120 are arranged, a first area 106 including a first drive circuit 116 a for outputting a scan signal to the display area 112, and a first area 106 adjacent to the first area 106. A second region 108, a terminal portion 114 disposed at an end of the base member 102, and a third region 110 including a second drive circuit 116b disposed adjacent to the terminal portion 114 and outputting a data signal to the display unit 112. ,including. The second area 108 is an area between the first area 106 and the third area 110, and is an area in which the wirings 118 such as data signal lines and power supply lines are provided.

The display unit 112 included in the first area 106 has a plurality of pixels 120 arranged, and forms a screen on which information such as characters and images is displayed. The first drive circuit 116 a disposed along the display unit 112 outputs a scan signal to the pixel 120. A plurality of terminal electrodes are arranged in the terminal portion 114 included in the third region 110, and connected to the flexible printed wiring board. The second drive circuit 116 b is disposed in an area between the display portion 112 and the terminal portion 114, and has a function of outputting a data signal (video signal) to the pixel 120. In the second region 108, a wiring 118 connecting the second drive circuit 116b and the display portion 112 is provided.

The pixel 120 includes a display element and a thin film transistor which drives the display element. As a display element, an organic electroluminescent element (hereinafter referred to as “an organic electroluminescent element (hereinafter referred to as“ an organic electroluminescent element (hereinafter referred to as “an organic EL material”)) is provided between a pair of electrodes distinguished as an anode and a cathode. Or a liquid crystal element in which a liquid crystal layer is provided between a pair of electrodes, or an electrophoresis element in which a fluid having polarity is disposed between a pair of electrodes. In the vicinity of the display portion 112, a common contact 122 which applies a common potential to one electrode of the display element is disposed.

In the first drive circuit 116a, a circuit including a shift register or the like is formed using a thin film transistor. The second drive circuit 116 b is formed, for example, of a bare chip integrated circuit and mounted on the base member 102.

The base member 102 is flexible and can be bent and bent. Such a base member 102 is formed using an organic resin material. For example, as the base member 102, a polymer material (imide) containing an imide bond in a repeating unit, a polymer material (polyamide) made by bonding a large number of monomers by an amide bond, or the like is applied. Such a base member 102 has a thickness of 5 μm to 50 μm, for example 10 μm. A glass substrate having a thickness of about 100 μm to 200 μm can also be used as another member constituting the base member 102. In this case, it is preferable to use an organic resin film by laminating for improvement of impact resistance.

The second area 108 is an area where the base member 102 is bent. The display device 100 according to the present embodiment has a structure in which the base member 102 can be bent along the X1-X2 line adjacent to the display unit 112. The wiring 118 disposed in the second region 108 is similarly bent by bending the base member 102. The second region 108 includes a through groove 126 penetrating an insulating layer provided on the first surface of the base member 102 in a region including the X1-X2 line assumed to be a bending line. The details of the through groove 126 will be described with reference to FIG. The through groove 126 may be provided continuously from one end to the other end of the base member 102 as shown in FIG. 1, or may be selectively provided in a region overlapping the wiring 118. In other words, the through groove 126 may be discontinuously provided corresponding to the arrangement of the wiring 118.

FIG. 2 shows a simplified stack structure of the display device 100. The cross-sectional structure shown in FIG. 2 corresponds to the line A1-A2 shown in FIG. The display device 100 includes a driving element layer 132 and a display element layer 134 on the first surface of the base member 102. The driving element layer 132 and the display element layer 134 are disposed in the first region 106. The driving element layer 132 is provided on the first surface of the base member 102, and the display element layer 134 is stacked on the driving element layer 132. The display portion 112 and the first drive circuit 116 a are formed by the drive element layer 132 and the display element layer 134. The top and side surfaces of the display element layer 134 are covered by the sealing layer 136. An optical film 138 is disposed on the upper layer side of the sealing layer 136.

The display element layer 134 includes a plurality of display elements. For example, a light emitting element is used as the display element. As a light emitting element, an organic electroluminescent element (hereinafter, also referred to as "organic EL element") in which a light emitting layer is formed of an organic electroluminescent material (hereinafter, also referred to as "organic EL material") is suitably used. Be Further, the display element layer 134 is configured using a liquid crystal element in which a liquid crystal layer is provided between a pair of electrodes instead of a light emitting element, and an electrophoresis element for controlling fluid of particles having polarity by the action of an electric field. May be

In the drive element layer 132, a pixel circuit and a drive circuit are formed by active elements such as transistors, and passive elements such as capacitors and resistors. In the driving element layer 132, an insulating layer, a semiconductor layer, and a conductive layer are appropriately stacked in order to form these circuits. The transistor in the driving element layer 132 and the display element in the display element layer 134 are electrically connected.

The sealing layer 136 is provided to protect the display element layer 134 from water vapor contained in air. The sealing layer 136 includes an inorganic insulating film having a low water vapor permeability to block water vapor. For example, the sealing layer 136 is provided in a structure in which the upper layer side and the lower layer side of the organic insulating film are sandwiched by an inorganic insulating film having a low water vapor permeability.

As the optical film 138, a functional film such as a retardation film, a polarizing film, an antireflective film, or a transparent film having no optical anisotropy is used. The optical film 138 may be configured by combining one or more of these functional films. For example, the optical film 138 has a structure in which a transparent film having no optical anisotropy and a polarizing film are laminated from the sealing layer 136 side. An antireflective film may be further laminated on the polarizing film.

In the third region 110, the terminal portion 114 is disposed at one end of the base member 102. The second drive circuit 116 b is, for example, a bare chip (integrated circuit not packaged), and is mounted on the base member 102. The terminal portion 114 and the second drive circuit 116 b are exposed from the sealing layer 136 and the optical film 138. That is, the third region 110 is a region where the sealing layer 136 and the optical film 138 are not disposed.

In the second region 108, the insulating layer 124 extends from the driving element layer 132, and the wiring 118 is provided in contact with the insulating layer 124. The wiring 118 extends from the drive element layer 132 to the third region 110 in which the second drive circuit 116 b and the terminal portion 114 are disposed. The wiring 118 may be covered by the resin layer 130 in the second region 108. The resin layer 130 is provided to cover substantially the entire surface of the second region 108. The insulating layer 124 is provided with a through groove 126.

The through groove 126 exposes the upper surface of the base member 102. The side surface of the through groove 126 has a plurality of stepped steps. The side wall of the through groove 126 has a plurality of steps. The plurality of steps provided on the side wall of the through groove 126 alleviates the steep rise of the side wall. That is, in the through groove 126, the side wall surface does not rise sharply from the groove bottom (the upper surface of the base member 102) to the groove upper portion (the upper surface of the insulating layer 124). . The wire 118 is disposed across the through groove 126. The wiring 118 is disposed along the plurality of steps on the side wall surface of the through groove 126. In this manner, the interconnections 118 are prevented from breaking in the region crossing the through groove 126.

A support member 104 may be provided on the second surface of the base member 102. The support member 104 is provided in the area corresponding to the first area 106 and the third area 110, and the opening 140 is provided in the area corresponding to the second area 108. By providing the support member 104, the display device 100 can be made more rigid in the regions corresponding to the first region 106 and the third region 110. On the other hand, the second area 108 where the support member 104 is not provided has lower rigidity than the first area 106 and the third area 110. Thereby, the second area 108 can be defined as a bending area of the display device 100. In other words, by providing the opening 140 in the support member 104, the region overlapping with the opening 140 can be used as a bending region of the display device 100.

FIG. 3 shows a state in which the base member 102 is bent to the second surface side in the second region 108. By bending the base member 102, the wiring 118 and the resin layer 130 can also be bent. Also, the through groove 126 is included in the area to be bent. When the thickness of the base member 102 is 10 μm to 50 μm, the radius of curvature of the first region 106 can be, for example, 0.1 mm to 10 mm, preferably 0.5 mm to 5 mm. The radius of curvature of the second region 108 does not have to be constant, and the radius of curvature may change continuously. The angle (bending angle) at which the base member 102 is bent can be set in the range of 0 degree to 180 degrees.

The second drive circuit 116 b and the terminal portion 114 are disposed on the rear surface side of the display unit 112 by bending the base member 102 in the second region 108 to the second surface side opposite to the first surface. As a result, a part of the frame area of the display device 100 is hidden behind the display unit 112, and the frame can be substantially narrowed. In other words, since the terminal area 114 and the second drive circuit 116 b are disposed, the third area 110 is a wide area in the frame area. Therefore, by bending the base member 102 so that the third region 110 is disposed on the back surface of the display unit 112, it is possible to more effectively narrow the frame.

The insulating layer 124 in the second region 108 is provided with a through groove 126. In other words, peeling and cracking of the insulating layer 124 are suppressed by providing the through groove 126 from which the insulating layer 124 is removed in the region where the base member 102 is bent. Furthermore, by providing a plurality of steps on the side wall surface of the through groove 126, the stress acting on the interconnection 118 crossing the through groove 126 is dispersed. Thus, the wire 118 is prevented from being broken or peeled off. Since the display device 100 is bent in the area where the through groove 126 is provided, the second area 108 can also be referred to as a bending area.

FIG. 4 shows a cross-sectional structure of the pixel 120 in the display device 100. The pixel 120 includes at least one transistor 142, a light emitting element 144, and a capacitive element 146. The transistor 142, the light emitting element 144, and the capacitor 146 are electrically connected. The voltage applied to the gate of the transistor 142 controls the current (drain current) flowing between the source and the drain. The light emission intensity of the light emitting element 144 is controlled by the drain current. The gate voltage is applied by connecting between the gate and the source of the transistor 142, and the capacitor 146 is provided to keep the gate voltage constant.

In FIG. 4, the driving element layer 132 includes a first insulating layer 150, a semiconductor layer 152, a second insulating layer 154, a gate electrode 156, a third insulating layer 158, a first wiring 118 a, a fourth insulating layer 162, and a capacitor electrode 164. , The fifth insulating layer 166, and the first electrode 168. The display element layer 134 includes a first electrode 168, a sixth insulating layer 170, an organic layer 172, and a second electrode 174. In addition, the sealing layer 136 includes a first inorganic insulating film 178, an organic resin film 180, and a second inorganic insulating film 182.

A first insulating layer 150 is provided on the first surface of the base member 102. Since the first insulating layer 150 is provided on the lower layer side of the semiconductor layer 152, the first insulating layer 150 is also referred to as a base insulating layer. The first insulating layer 150 is formed by laminating one inorganic insulating film or a plurality of inorganic insulating films. For example, the first insulating layer 150 has a structure in which a silicon oxide film, a silicon nitride film, and a silicon oxide film are stacked in this order from the base member 102 side. The first insulating layer 150 has a thickness of 100 nm to 10000 nm, preferably 400 nm to 800 nm, for example, 600 nm.

The transistor 142 provided in the driving element layer 132 has a structure in which the semiconductor layer 152, the second insulating layer 154 (gate insulating layer), and the gate electrode 156 are stacked. The semiconductor layer 152 is formed of a semiconductor material such as amorphous silicon or polycrystalline silicon, or a metal oxide. The semiconductor layer 152 is insulated from the gate electrode 156 by the second insulating layer 154. The second insulating layer 154 is formed of an inorganic insulating film such as a silicon oxide film or a silicon oxynitride film. The second insulating layer 154 is thinner than the first insulating layer 150. For example, the second insulating layer 154 has a thickness of 50 nm to 200 nm, for example, 100 nm.

A third insulating layer 158 is provided on the upper layer side of the gate electrode 156. The first wiring 118 a is provided on the upper side of the third insulating layer 158. The first wiring 118 a forms a contact with the semiconductor layer 152 through a contact hole formed in the third insulating layer 158. The third insulating layer 158 is manufactured using an inorganic insulating film. For example, the third insulating layer 158 is formed by stacking a single layer of a silicon oxide film, a silicon nitride film, and a silicon oxide film. The third insulating layer 158 is used as an interlayer insulating film which insulates the gate electrode 156 and the first wiring 118a. Therefore, the third insulating layer 158 has a thickness of 100 nm to 20000 nm, preferably 500 nm to 10000 nm, for example, 700 nm. In addition, the gate electrode 156 and the first wiring 118 a are manufactured using a metal film such as aluminum (Al), molybdenum (Mo), titanium (Ti), tungsten (W) or the like. For example, the first wiring 118a has a three-layer structure in which a titanium (Ti) film is provided on the lower layer side and the upper layer side of the aluminum (Al) film.

A fourth insulating layer 162 is provided in the upper layer of the first wiring 118a. The fourth insulating layer 162 is used as a planarizing film which embeds an uneven surface by the semiconductor layer 152, the gate electrode 156, the first wiring 118a, and the like and planarizes the surface. The fourth insulating layer 162 is formed using an organic insulating material such as polyimide resin or acrylic resin.

A capacitive electrode 164 is provided on the top surface of the fourth insulating layer 162, and a fifth insulating layer 166 is further formed. The first electrode 168 is provided on the top surface of the fifth insulating layer 166. The first electrode 168 is electrically connected to the first wiring 118 a through a contact hole penetrating the fifth insulating layer 166 and the fourth insulating layer 162. The first electrode 168 is provided to overlap with the capacitor electrode 164 with the fifth insulating layer 166 interposed therebetween. A region where the capacitor electrode 164, the fifth insulating layer 166, and the first electrode 168 overlap is the capacitor 146. As the fifth insulating layer 166 used as a dielectric film of the capacitor 146, an inorganic insulating film such as silicon nitride, silicon oxide, silicon oxynitride or the like is used.

The display element layer 134 includes the light emitting element 144 in which the first electrode 168, the organic layer 172, and the second electrode 174 are stacked. The periphery of the first electrode 168 is covered with a sixth insulating layer 170 having an opening, and the inner region is exposed. The organic layer 172 is provided to cover the surface of the sixth insulating layer 170 from the top surface of the first electrode 168 exposed from the sixth insulating layer 170. The second electrode 174 is provided to cover the top surfaces of the organic layer 172 and the sixth insulating layer 170. In the pixel 120, a region corresponding to the opening of the sixth insulating layer 170 is a light emitting region. The sixth insulating layer 170 is made of an organic insulating material to form a smooth level difference at the open end that exposes the first electrode 168. An acrylic resin, a polyimide resin, a polyamide resin etc. are used as an organic insulation material.

The organic layer 172 is manufactured using a low molecular weight or high molecular weight organic EL material. When a low molecular weight organic EL material is used, the organic layer 172 is added to the light emitting layer containing the organic EL material, and the carrier injection layer (hole injection layer, electron injection layer) to sandwich the light emitting layer, the carrier transport layer ( A hole transport layer, an electron transport layer, etc. are suitably provided. For example, the organic layer 172 has a structure in which the light emitting layer is sandwiched between the hole injection layer and the electron injection layer. In addition to the hole injection layer and the electron injection layer, the organic layer 172 is appropriately added with a hole transport layer, an electron transport layer, a hole block layer, an electron block layer, and the like.

In the present embodiment, the light emitting element 144 is a so-called top emission type that emits the light emitted from the organic layer 172 to the second electrode 174 side. The first electrode 168 is manufactured to include a metal film or a metal film so as to reflect light emitted from the organic layer 172. For example, the first electrode 168 is preferably made of a metal film such as aluminum (Al) or silver (Ag) having a high light reflectance in the visible light band. In addition, the first electrode 168 is made of indium tin oxide (hereinafter also referred to as “ITO”), indium zinc oxide (hereinafter also referred to as “IZO”), zinc oxide to which aluminum is added (hereinafter referred to as “AZO”). A transparent conductive film such as zinc oxide (hereinafter also referred to as "GZO") to which gallium is added and a metal film may be stacked. The second electrode 174 is made of a transparent conductive film such as ITO, IZO, AZO, GZO or the like in order to transmit light emitted from the organic layer 172. The second electrode 174 is provided over substantially the entire surface of the display unit 112.

The sealing layer 136 is provided on the upper layer side of the second electrode 174. As shown in FIG. 4, the sealing layer 136 may have a structure in which a first inorganic insulating film 178, an organic resin film 180, and a second inorganic insulating film 182 are stacked. As the first inorganic insulating film 178 and the second inorganic insulating film 182, an inorganic insulating material such as a silicon nitride film or an aluminum oxide film is used. As the organic resin film 180, an acrylic resin, a polyimide resin, a polyamide resin, an epoxy resin or the like is used. The first inorganic insulating film 178 and the second inorganic insulating film 182 have a thickness of 0.1 μm to 10 μm, preferably 1 μm to 7 μm, for example, 5 μm. The organic resin film 180 has a thickness of 1 μm to 20 μm, for example, 10 μm. An optical film 138 is provided on the top surface of the sealing layer 136. The optical film 138 also has a function as a protective member that protects the display element layer 134 and the drive element layer 132.

FIG. 5 shows a cross-sectional structure corresponding to line B1-B2 shown in FIG. That is, FIG. 5 shows a cross-sectional structure of a part of the first region 106, the third region 110, and the second region 108.

The first region 106 includes the common contact 122. The common contact 122 is a region where the second electrode 174 extending from the pixel 120 is connected to the common wiring 160. The common wire 160 may be configured by a first common wire 160 a provided on the third insulating layer 158 and a second common wire 160 b interposed between the second electrode 174. The first common wiring 160 a is formed of a conductive film similar to the conductive film forming the first wiring 118 a, and the second common wiring 160 b is formed of a conductive film similar to the first electrode 168 of the light emitting element 144.

The first region 106 includes an open region 184 in which the fourth insulating layer 162 and the sixth insulating layer 170 formed of an organic insulating material are removed. The opening region 184 has a structure in which the sixth insulating layer 170 is divided and the first insulating layer 150, the second insulating layer 154, the third insulating layer 158, and the fifth insulating layer 166 are stacked on the bottom surface. The first insulating layer 150, the second insulating layer 154, the third insulating layer 158, and the fifth insulating layer 166 are formed of an inorganic insulating film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film. In the opening region 184, the sixth insulating layer 170 is divided (sixth insulating

layers

170a and 170b). The sixth insulating

layers

170 a and 170 b divided by the opening region 184 serve as a blocking member of the organic resin film 180 in the manufacturing process, and have a function of preventing the outflow to the end of the first inorganic insulating film 178.

On the other hand, the organic resin film 180 forming the sealing layer 136 is provided so as not to exceed the sixth insulating layer 170 a. Therefore, in the region beyond the end of the organic resin film 180, the first inorganic insulating film 178 and the second inorganic insulating film 182 are provided in close contact. With such a configuration, the organic resin film 180 that constitutes the sealing layer 136 has a structure that is not exposed to the outside. This structure can prevent moisture from entering the fourth insulating layer 162. The second area 108 may also be referred to as a moisture blocking area.

The first region 106 is provided with an optical film 138 via a sealing resin 139. The end of the optical film 138 is disposed to coincide with or outside the end of the sixth insulating layer 170 b. By arranging the optical film 138 so as to cover the end of the sixth insulating layer 170b, the display unit 112 can be protected securely.

In the first region 106, the second wiring 118b is provided between the second insulating layer 154 and the third insulating layer 158. The third wiring 118 c provided on the upper layer side of the third insulating layer 158 is extended to the second region 108. The second region 108 has a structure in which a first insulating layer 150 in contact with the base member 102, a second insulating layer 154 on the first insulating layer 150, and a third insulating layer 158 are stacked. The through groove 126 exposes the first surface of the base member 102 and separates the insulating layers 124. The third wiring 118 c is a side wall surface of the through groove 126 (a side surface of the first insulating layer 150, the second insulating layer 154, and the third insulating layer 158) from the upper surface of the third insulating layer 158 and the third surface of the base member 102. It is arranged in contact with one side. By providing the through groove 126 in the bent region of the base member 102, peeling and cracking of the first insulating layer 150, the second insulating layer 154, the third insulating layer 158, and the fifth insulating layer 166 are suppressed.

In the through groove 126, the side surfaces of the first insulating layer 150 and the third insulating layer 158 have at least one step portion 127. By providing one or more steps on the side surfaces of the first insulating layer 150 and the third insulating layer 158, a plurality of steps are provided on the side wall surface of the through groove 126 as a whole. The height of the step provided in each of the first insulating layer 150 and the third insulating layer 158 is preferably half or less of the film thickness. By providing the level | step difference of such height on the side surface of each insulating layer, the steepness of the level | step difference with respect to the depth direction of the penetration groove 126 can be relieve | moderated. Note that since the second insulating layer 154 is thinner than the first insulating layer 150 and the third insulating layer 158, it is not necessary to provide a step. However, in the through groove 126, the side surface of the second insulating layer 154 may include a step. In addition, the end of the second insulating layer 154 is on the outer side than the end of the third insulating layer 158 and the inner side of the end of the first insulating layer 150 in the through groove 126. Oneself may constitute one level difference.

The third wiring 118 c is disposed across the through groove 126. The third wiring 118c is formed, for example, in the same structure as the first wiring 118a. The third wiring 118 c disposed in the second region 108 is disposed along the side surfaces of the third insulating layer 158, the second insulating layer 154, and the first insulating layer 150. The through groove 126 has a step portion 127 including a plurality of steps on the side wall surface, whereby the steepness of the groove depth (the height from the surface of the base member 102 to the upper surface of the third insulating layer 158) is alleviated. Ru. The third wiring 118c is provided along the step-like stepped surface in the through groove 126, whereby disconnection is prevented, and as will be described later, a short circuit with an adjacent wiring due to patterning failure is prevented. . Further, even when the base member 102 is bent in the second region 108, concentration of bending stress on the third wiring 118c at the end of the through groove 126 can be suppressed.

The second region 108 is provided with a resin layer 130 in which the third wiring 118 c is embedded. The resin layer 130 is used as a protective member for the third wiring 118 c. The resin layer 130 is provided with a thickness not exceeding the height of the optical film 138. As the resin layer 130, for example, an acrylic resin, an epoxy resin, a polyimide resin, or the like is used.

The second drive circuit 116 b is formed, for example, of a bare chip integrated circuit and mounted on the base member 102. The terminal portion 114 includes a structure in which the first insulating layer 150, the second insulating layer 154, and the third insulating layer 158 are stacked, and includes the terminal electrode 148 provided on the upper surface of the third insulating layer 158. The terminal electrode 148 is formed of, for example, a first terminal electrode layer 149a and a second terminal electrode layer 149b. The first terminal electrode layer 149a is formed of the same conductive layer as the conductive layer forming the third wiring 118c, and the second terminal electrode 148b is formed of the same conductive layer as the first electrode 168 of the light emitting element 144. .

The details of the second area 108 will be described with reference to FIGS. 6A and 6B. 6A shows a plan view of the second region 108, and FIG. 6B shows a cross-sectional structure corresponding to line C1-C2 shown in the drawing. The first region 106 has a region in which the first insulating layer 150, the second insulating layer 154, and the third insulating layer 158 are stacked, and the through groove 126 from which the insulating layer is removed.

In the through groove 126, the first insulating layer 150, the second insulating layer 154, and the third insulating layer 158 are removed, and the bottom surface 129 where the base member 102 is exposed, the first insulating layer 150, the second insulating layer 154, and And a side wall surface 128 on which the side surface of each layer of the third insulating layer 158 is exposed. Side wall surface 128 has a stepped portion 127. The stepped portion 127 is formed by at least steps formed on the side surfaces of the first insulating layer 150 and the third insulating layer 158. For this reason, in the step portion 127, a plurality of steps are provided in a step-like manner. The third wiring 118 c is disposed to cross the through groove 126 from the top surface of the third insulating layer 158 along the side wall surface 128 and the bottom surface 129.

Although FIG. 6B shows an aspect in which one step is provided in each of the first insulating layer 150 and the third insulating layer 158, the present embodiment is not limited to this, and a plurality of side surfaces of each insulating layer are provided. A level difference may be provided. Further, although the second insulating layer 154 is smaller in thickness than the first insulating layer 150 and the third insulating layer 158, no stepped portion is provided, but at least one stepped portion is also provided in the second insulating layer 154. It may be provided. In addition, by disposing the end of the second insulating layer 154 outside the third insulating layer 158 and inside the end of the first insulating layer 150, the second insulating layer 154 can partially form a step. It may be formed.

As shown in FIG. 6B, by providing the plurality of step portions on the side wall surface of the through groove 126, the height (difference in height) of the step per step is reduced. With such a configuration, the step coverage with the third wiring can be improved, and film thickness uniformity and line width uniformity can be achieved.

A through groove 126 having a step portion 127 as shown in FIG. 6B is manufactured by etching an insulating layer. In the structure in which the first insulating layer 150, the second insulating layer 154, and the third insulating layer 158 are stacked, in order to form the through groove 126, it is necessary to form a resist mask by a photolithography process. In this case, in order to provide the step on the side wall surface 128 of the through groove 126, the increase in the number of steps is prevented by using multi-tone exposure to form resist masks having different film thicknesses corresponding to the step. can do.

In the multi-tone exposure method, a multi-tone photomask is used. A multi-tone photomask is provided with a slit equal to or lower than the resolution of the exposure machine as a mask pattern formed on a glass substrate, and the slit blocks a part of light to realize intermediate exposure, Although a halftone mask is known that uses a film to realize an intermediate exposure, in the present embodiment, both multi-tone photomasks can be used. By performing exposure using a multi-gradation photomask, areas of an exposed portion, an intermediate exposed portion, and an unexposed portion are formed on the photoresist film, and the film thickness can be made different.

FIG. 7 shows an aspect in which a resist mask 190 is formed in the first region 106 using the multi-tone photomask 186 when forming the through groove 126. The mask pattern 187 of the multi-tone photomask 186 is designed to have different light transmittances in accordance with the form of the stepped portion 127. By exposing the resist film 188 using the multi-tone photomask 186, a plurality of regions with different exposure amounts are formed. Thereafter, the resist film 188 is developed to form resist masks 190 having different film thicknesses corresponding to the regions of the stepped portions 127. Specifically, a resist mask 190 having a thin film region and a thick film region corresponding to the step shape of the third insulating layer 158 is formed. By etching the third insulating layer 158 using such a resist mask 190, a step can be formed on the side surface of the third insulating layer 158. Since the third insulating layer 158 is formed of a silicon oxide film or a silicon nitride film, it is preferable to use dry etching to etch these inorganic insulating films continuously. In dry etching, anisotropic etching is preferably performed using a gas such as carbon tetrafluoride (CF ₄ ) or methane trifluoride (CHF ₃ ) as an etching gas. A stepped portion can be similarly formed for the first insulating layer 150 as well.

The through groove 126 is formed by etching the first insulating layer 150, the second insulating layer 154, and the third insulating layer 158. In this process, by applying the multi-gradation exposure method, a plurality of steps can be provided on the side wall surface 128 of the through groove 126 only by using a single photomask. In the multi-tone exposure method, a multi-tone photomask is used. A multi-tone photomask is provided with a slit equal to or less than the resolution of the exposure machine as a mask pattern formed on a glass surface, and the slit blocks a part of light to realize intermediate exposure, Although a halftone mask is known that uses a film to realize an intermediate exposure, in the present embodiment, both multi-tone photomasks can be used. By performing exposure using a multi-gradation photomask, areas of an exposed portion, an intermediate exposed portion, and an unexposed portion are formed on the photoresist film, and the film thickness can be made different.

In addition, the form of the side wall surface 128 in the penetration groove 126 is not limited to what is shown to FIG. 6A and 6B. For example, as shown in FIG. 8, the side surfaces of the first insulating layer 150, the second insulating layer 154, and the third insulating layer 158 may be provided substantially vertically. Even if the side wall surface 128 is erected vertically, the height per step is mitigated by including the plurality of step portions 127, and the defect of the third wiring 118c disposed in the first region 106 is prevented. can do.

According to the present embodiment, peeling and cracking of the insulating film can be prevented by providing the through groove 126 from which the base insulating film and the interlayer insulating film are removed in the region where the display device 100 is bent. In this case, by providing a plurality of steps on the side surface of the through groove 126, it is possible to prevent peeling and disconnection of the wiring crossing the through groove 126.

Second embodiment:
The present embodiment shows an example of a method of manufacturing the display device 100. In the present embodiment, the display device 100 has the same configuration as that shown in the first embodiment. 9A, 10A, 12A, 13A, and 10A show structures corresponding to the cross section of the pixel 120 in the description of this embodiment, and FIGS. 9B, 10B, 12B, 13B, and 13B. FIG. 10B shows a structure corresponding to a part of the first region 106 and the second region 108.

9A and 9B illustrate stages in which the transistor 142 is formed in the pixel 120 and the second wiring 118b is formed in the first region 106. A first resist mask 190 a is formed on the third insulating layer 158 using a multi-tone mask (halftone mask). The first resist mask 190 a has a pattern for processing the third insulating layer and the second insulating layer 154. Specifically, the first resist mask 190a has a first opening pattern 192a for forming a contact hole reaching the source region and the drain region formed in the semiconductor layer 152 in the region of the pixel 120, and a through groove in the second region 108. And a second opening pattern 192 b for forming the first electrode 126. The first resist mask 190a is formed such that the inner region of the second opening pattern 192b has a thinner resist film thickness than the other regions. Such a form of the first resist mask 190a is, for example, applying a positive resist on the base member 102, and the exposure amount of the inner region of the second opening pattern 192b is smaller than the exposure amount of the inner removal region. It is fabricated by exposure using a multi-tone photomask (halftone mask) so as to decrease.

10A and 10B, the contact hole 167a penetrating the third insulating layer 158 and the second insulating layer 154 is formed in the pixel 120 by the first resist mask 190a, and the third insulating layer 158 is formed in the second region 108. And the third insulating layer 158 and the second insulating layer 154 are removed in the region of the through hole 126 and the contact hole 167b for exposing the second wiring 118b. In the second region 108, a step is formed on the side surface portion of the third insulating layer 158 by forming the first resist mask 190a using a multi-tone photomask.

11A and 11B illustrate an embodiment in which the second resist mask 190 b is formed on the third insulating layer 158. The entire surface of the pixel 120 is covered with the second resist mask 190b, and the second region 108 is a resist film in the region corresponding to the through groove 126, like the first resist mask 190a, in the inner region of the third opening pattern 192c. An area of reduced thickness is formed. The first insulating layer 150 is etched using the second resist mask 190 b until the surface of the base member 102 is exposed.

12A and 12B show a state in which the through groove 126 is formed in the second region 108. FIG. In the pixel 120, the multi-tone exposure method is not applied, so the contact hole 167a is formed in the third insulating layer 158 in a normal form. In the second region 108, a step is formed in each of the third insulating layer 158 and the first insulating layer 150 by two-time multi-tone exposure. That is, in the through groove 126, a plurality of steps are formed on the side wall surface 128.

13A shows an aspect in which the first wiring 118a is formed in the pixel 120, and FIG. 13B shows that the first common wiring 160a is formed in the first region 106, and the third wiring 118c is formed in the second region 108. Indicates the stage. The first wiring 118a, the first common wiring 160a, and the third wiring 118c are formed by forming a conductive film over the third insulating layer 158 and patterning the conductive film through a photolithography process. When the third resist mask 190c for forming the third interconnection 118c is formed, the side wall surface 128 of the through groove 126 has a plurality of steps, so the height of the step per step is reduced compared to the case where there is no step. ing. Thereby, the photoresist is sufficiently exposed also on the side wall surface 128 of the through groove 126, and the resist is prevented from remaining due to the insufficient exposure. As a result, even when a plurality of third wires 118c are juxtaposed in the second region 108, a short circuit between adjacent wires is prevented. That is, short circuit defects between adjacent wirings can be prevented, and the manufacturing yield can be improved.

14A and 14B, after forming the first wiring 118a, the first common wiring 160a, and the third wiring 118c, the fourth insulating layer 162, the capacitor electrode 164, the fifth insulating layer 166, the first electrode 168, the A step of forming the two common wires 160b, the sixth insulating layer 170, the organic layer 172, and the second electrode 174 is shown. In the second region 108, all of the fourth insulating layer 162 and the layers provided thereabove are removed. Since the second region 108 is provided with a plurality of steps on the side wall surface 128, the third wiring 118c can be formed by the same member (the same conductive film) as the first wiring 118a formed in the first region 106. Ru. Furthermore, when the sealing layer 136, the optical film 138, the resin layer 130, and the like are provided, the display device 100 shown in FIGS. 5, 6A, and 6B is manufactured.

According to the present embodiment, by using the multi-tone photomask (halftone) mask, the through groove 126 can be formed without significantly increasing the number of steps, and the sidewall surface 128 of the through groove 126 can be formed. Can have a plurality of steps. In this case, when the wiring pattern is exposed in the second region 108 by the photolithography process, the photoresist can be reliably exposed because the stepped portion is provided. When the height of the step portion is high, the step portion can not be sufficiently exposed in the photolithography step, and the resist film remains in the step portion. When the wiring pattern is processed in such a situation, a patterning failure occurs, and a failure occurs in which adjacent wirings are short-circuited. However, according to the present embodiment, patterning defects can be eliminated by providing the plurality of step portions on the side wall surface 128 of the through groove 126.

Third embodiment:
FIG. 15 shows a form of the through groove 126 of the display device 100 according to the present embodiment. As shown in FIG. 15, the through groove 126 includes a bottom surface 129 and a side wall surface 128. The side wall surface 128 is provided with a step in the third insulating layer 158. On the other hand, the first insulating layer 150 is not provided with a step, and has an inclined side (a tapered side) which opens upward.

In forming the through groove 126, the third insulating layer 158 and the second insulating layer 154 are provided with a resist mask using a multi-gradation photomask (halftone mask) as in the second embodiment, and are processed by dry etching. Do. In this process, since the formation of the contact hole in the first region 106 is also performed simultaneously, it is preferable to process precisely by dry etching.

As shown in FIG. 16, the processing of the first insulating layer 150 is performed by wet etching by providing a resist mask 190 d using a normal photomask. In wet etching, the side surfaces of the first insulating layer 150 can have an inclination angle by forming an undercut. For example, when processing the first insulating layer 150, the adhesion of the resist mask 190d may be reduced and wet etching may be performed so as to promote undercut. In addition, the density of the first insulating layer 150 is made different in the film thickness direction (specifically, the density on the boundary surface with the resist mask 190 d is reduced with respect to the density on the base member 102 side), and wet etching is performed. Doing so promotes undercutting. The inclination angle of the side surface of the first insulating layer 150 is in the range of 15 ° to 80 °, preferably 30 ° to 60 °.

Thus, the step of the through groove 126 can be relaxed also by inclining the side surface of the first insulating layer 150. In particular, by setting the side surface of the first insulating layer 150 as the inclined surface, the steepness of the step can be alleviated at the portion where the third wiring 118c rises from the bottom surface 129 of the through groove 126 to the side wall surface 128.

By processing the first insulating layer 150 by wet etching, etching of the base member 102 can be prevented, and undercutting of the lower surface of the first insulating layer 150 can be prevented. Thereby, disconnection of the third wiring 118c can be prevented. Further, by changing the first insulating layer 150 to wet etching, it is not necessary to use a multi-tone photomask (halftone mask), and the cost of the photomask can be reduced.

100: display device 102: base member 104: support member 106: first region 108: second region 110: third region 112: display Portions 114: Terminal portions 116: Drive circuits 118: Wirings 120: Pixels 122: Common contacts 124: Insulating layers 126: Through grooves 127 · · · Stepped portion, 128 · · · side wall surface, 129 · · · bottom surface · 130 · · · resin layer, 132 · · · drive element layer, 134 · · · display element layer, 136 · · · sealing layer, 138: optical film, 139: sealing resin, 140: opening, 142: transistor, 144: light emitting element, 146: capacitive element, 148: terminal electrode, 149 ... terminal electrode layer, 150 ... first insulating layer, 152 ... Semiconductor layer, 154: second insulating layer, 156: gate electrode, 158: third insulating layer, 160: common wiring, 162: fourth insulating layer, 164: capacitance electrode 166: fifth insulating layer 167: contact hole 168: first electrode 170: sixth insulating layer 172: organic layer 174: second electrode 178 ... First inorganic insulating film, 180 ... Organic resin film, 182 ... Second inorganic insulating film, 184 ... Opening area, 186 ... Multi-tone photomask, 187 ... Mask pattern , 188: resist film, 190: resist mask, 192: opening pattern

Claims

A base member having a first surface and a second surface opposite to the first surface;
A first region including a display portion disposed on the first surface of the base member;
A second region including a wire disposed on the first surface of the base member;
A third region including a terminal portion disposed on the first surface of the base member, and a drive circuit outputting a data signal to the display portion;
An insulating layer disposed over the first area and the second area on the first surface of the base member;
Have
The insulating layer has a through groove having a bottom surface which is provided along the display portion and exposes the base member in the second region, and a side wall surface including a plurality of steps.
The display device is characterized in that the wiring intersects the through groove.
The said insulating layer is a 1st insulating layer which contact | connects the said base member, The 2nd insulating layer on the said 1st insulating layer, The 3rd insulating layer on the said 2nd insulating layer is described in Claim 1 Display device.
The display device according to claim 2, wherein the through groove includes at least one level difference on each side wall surface of the first insulating layer and the third insulating layer.
The display device according to claim 2, wherein the side wall surface of the first insulating layer has an inclined surface, and the through groove has one or more stepped portions on the side wall surface of the third insulating layer.
The display device according to claim 1, wherein the through groove has a step-like step on a side wall surface.
The display according to claim 3, wherein the height of each step of the first insulating layer and the third insulating layer is equal to or less than half the thickness of each of the first insulating layer and the third insulating layer. apparatus.
The display device according to claim 2, wherein the first insulating layer, the second insulating layer, and the third insulating layer are inorganic insulating films.
The display device according to claim 1, wherein the second region includes a resin layer covering the wiring.
The display device according to claim 1, wherein the base member is flexible.
The display device according to claim 9, wherein the base member is bent to the second surface side by the through groove.