The present invention relates to a display device.
In recent years, various display devices have been developed. Particularly, a display device including an organic light-emitting diode (OLED) and a display device including an inorganic light-emitting diode or a quantum dot light-emitting diode (QLED) have drawn a great deal of attention because these devices are capable of achieving lower power consumption, smaller thickness, higher picture quality, and the like.
For example, in the field of display devices provided with OLEDs, QLEDs, and the like, PTL 1 describes manufacturing of a display device using a vapor deposition mask capable of patterning a vapor deposition film with a higher precision in order to realize a display device of a higher resolution.
However, even in the case where the vapor deposition mask capable of patterning the vapor deposition film with a high precision as described in PTL 1 is used, dust may become adhered to the vapor deposition mask, or a cleaning liquid for the vapor deposition mask may remain in the vapor deposition mask.
When forming the vapor deposition film using the vapor deposition mask, contaminants, such as dust and a cleaning liquid adhered to the vapor deposition mask in this manner, may be transferred to an active matrix substrate side on which the vapor deposition film is formed. Due to the contaminant that has been transferred to the active matrix substrate side in this manner, for example, when plasma treatment is performed on a film that has been formed in a post process after a process of forming the vapor deposition film using the vapor deposition mask, the film formed on the contaminant may be affected by the contaminant, and film peeling or the like may occur.
The present invention has been conceived in light of the problem described above, and an object thereof is to provide a display device capable of preventing film peeling or the like from occurring due to a contaminant.
In order to solve the problem described above, a display device according to the present invention includes a display region in which a plurality of light-emitting elements are disposed, a frame region surrounding the display region, and a sealing layer, each of the light-emitting elements being provided with a first electrode, a second electrode formed above the first electrode, and a function layer formed between the first electrode and the second electrode. The second electrode includes an extending portion extending from the display region to the frame region, and overlaps all of the display region. A cap layer is provided above the extending portion to overlap at least part of an end portion of the extending portion, and the cap layer overlaps all of the display region. The sealing layer overlaps all of the second electrode and all of the cap layer.
According to an aspect of the present invention, it is possible to provide a display device capable of preventing film peeling or the like from occurring due to a contaminant.
A description follows regarding embodiments of the present invention, with reference to
(a) of
In the present embodiment, a case will be described as an example where an active matrix substrate 4 having a configuration described below is used, but the substrate is not particularly limited to this example, as long as the substrate includes an active element such as a thin film transistor element (a TFT element).
The active matrix substrate 4 illustrated in (a) of
Then, in the display region DA of the active matrix substrate 4, a plurality of TFT elements Tr are formed each including a semiconductor film 15, the inorganic insulating film 16, a gate electrode GE, the inorganic insulating film 18, the inorganic insulating film 20, and a source and drain wiring line SH. Further, in the display region DA of the active matrix substrate 4, a plurality of capacitance elements are formed each including a capacitance electrode (not illustrated) included in a capacitance wiring line CE formed directly above the inorganic insulating film 18, the inorganic insulating film 18, and a capacitance counter electrode (not illustrated) formed directly below the inorganic insulating film 18 and formed overlapping the capacitance electrode in the same layer as a layer forming the gate electrode GE.
Further, in the display region DA of the active matrix substrate 4, a first electrode 22 is formed in an upper layer overlying the interlayer insulating film 21, and a bank 23 is formed covering an edge of the first electrode 22. In addition, a lead portion 22′ is formed in the same layer as the first electrode 22 so as to extend across the display region DA and a frame region NA of the active matrix substrate 4.
In the present embodiment, three layers of a hole transport layer, a light-emitting layer, and an electron transport layer are formed on the first electrode 22 as a function layer 24, but no such limitation is intended, and layers other than the light-emitting layer, namely, the hole injection layer, the hole transport layer, the electron transport layer, and an electron injection layer may be omitted as appropriate, or the function layer 24 may be formed over the entire surface of the display region DA, without patterning the layer in a region SP within the bank 23 using a vapor deposition mask.
As illustrated in (a) of
In the display device 1 illustrated in (a) of
The sealing layer 6 is light-transmissive and includes a first inorganic sealing film 27, an organic sealing film 28 formed above the first inorganic sealing film 27, and a second inorganic sealing film 29 covering the organic sealing film 28. The sealing layer 6 that seals the light-emitting element layer 5 prevents water, oxygen and the like from penetrating the light-emitting element layer 5.
Each of the first inorganic sealing film 27 and the second inorganic sealing film 29 may be formed, for example, of a silicon oxide film, a silicon nitride film, or a silicon oxynitride film, or of a layered film of these, formed by CVD. The organic sealing film 28 is thicker than the first inorganic sealing film 27 or the second inorganic sealing film 29, is a light-transmitting organic film, and can be formed of a coatable photosensitive organic material such as a polyimide resin or an acrylic resin.
In the present embodiment, a case has been described as an example where the sealing layer 6 is formed by a layered body formed by three layers, but the sealing layer 6 is not limited to this example, and the sealing layer 6 may be formed by a single layer of the first inorganic sealing film 27, or by a layered body formed by five or more layers of an organic sealing film and an inorganic sealing film.
As illustrated in (a) of
Examples of the substrate 10 include a glass substrate having high heat resistance, but are not limited thereto.
Examples of the material of the resin layer 12 include a polyimide resin, an epoxy resin, and a polyamide resin, but are not limited thereto.
The barrier layer 3 is a layer that prevents moisture or impurities from reaching the TFT element Tr or the function layer 24 and can be formed, for example, of a silicon oxide film, a silicon nitride film or a silicon oxynitride film, or of a layered film of these films, formed by CVD.
The semiconductor film 15 is formed of low-temperature polysilicon (LTPS) or an oxide semiconductor, for example.
The gate electrode GE, the capacitance wiring line CE, and the source and drain wiring line SH are each formed of a single layer film or a layered film of metal, the metal including at least one of aluminum (Al), tungsten (W), molybdenum (Mo), tantalum (Ta), chromium (Cr), titanium (Ti), copper (Cu), and silver (Ag), for example.
The inorganic insulating films 16, 18, and 20 may each be formed, for example, of a silicon oxide (SiOx) film, a silicon nitride (SiNx) film, or a silicon oxynitride film, or of a layered film of these, formed by CVD.
The interlayer insulating film 21 may be formed, for example, of a coatable photosensitive organic material, such as a polyimide resin and an acrylic resin.
The first electrode (anode electrode) 22 can be formed by layering indium tin oxide (ITO) and an alloy including silver (Ag), and has light reflectivity.
The bank 23 can be formed, for example, of a coatable photosensitive organic material, such as a polyimide resin and an acrylic resin.
In the present embodiment, a case has been described as an example where the substrate 10 provided in the display device 1 is a glass substrate having high heat resistance, but no such limitation is intended. For example, the disclosure may be applied to a flexible display device that is obtained by irradiating the resin layer 12 with laser light through the substrate 10 provided in the display device 1, then peeling off the substrate 10 from the resin layer 12, and using the resin layer 12 as a flexible substrate. Furthermore, the flexible display device may be obtained by attaching a flexible substrate to a surface of the resin layer 12 from which the substrate 10 has been peeled off.
(b) of
As illustrated in (b) of
Further, as illustrated in (b) of
(a) of
As illustrated in (a) of
As illustrated in (a) of
As illustrated in (a) of
Note that although only the one mask opening formation region FEA and the one mask recess formation region HEA, each corresponding to the one active matrix substrate 4, are illustrated in the mask 30 illustrated in (a) of
For example, in some cases, a contaminant such as dust or a cleaning liquid for the mask may become adhered to or remain in the mask recess HK, which is the non-through-hole in the mask 30. When forming the function layer 24 using the mask 30, such a contaminant may be transferred to the active matrix substrate 4 side on which the function layer 24 is formed, and may become a contaminant on the active matrix substrate 4. Due to the contaminant on the active matrix substrate 4, for example, when the plasma treatment is performed on the second electrode 25 including the extending portion 25′, which is a film formed in a post process after a process of forming the function layer 24 using the mask 30, the second electrode 25 including the extending portion 25′ formed on the contaminant may be affected by the contaminant, and film peeling or the like may occur.
The mask 30 illustrated in
The function layer 24 illustrated in
Note that the function layer 24 is the layer including at least one of the hole injection layer, the hole transport layer, the light-emitting layer, the electron transport layer, and the electron injection layer, and refers to a vapor deposition film that is patterned in the region SP within the bank 23 using a vapor deposition mask.
(a) of
As illustrated in
On the side DRP, which is the drive circuit 50 side, of the active matrix substrate 40 illustrated in
On the other hand, on the sides other than the side DRP, which is the drive circuit 50 side, of the active matrix substrate 40, which are illustrated in (a) of
Further, this cap layer 26 is provided covering the entire surface of the display region DA, and is provided on the display device 1 as an optical adjustment member for adjusting light emitted from the light-emitting element 5. Therefore, for the cap layer 26, a material that can minimize a deterioration in brightness, light-emission characteristics, and the like of the light from the light-emitting element 5 is used.
On the sides other than the side DRP, which is the drive circuit 50 side, of the active matrix substrate 40, which are illustrated in (a) of
The second electrode 25 including the extending portion 25′ can be formed of a light-transmitting conductive material such as indium tin oxide (ITO) and indium zinc oxide (IZO), for example.
The light-emitting element 5 includes the first electrode 22, the function layer 24, and the second electrode 25. In the present embodiment, a case has been described as an example where the first electrode 22 is a light-reflective anode electrode, the second electrode 25 is a light-transmitting cathode electrode, and the light-emitting element 5 is a top-emitting type, but no such limitation is intended, and the first electrode 22 may be a light-transmissive cathode electrode, the second electrode 25 may be a light-reflective anode electrode, and the light-emitting element 5 may be a bottom-emitting type.
The cap layer 26 may be formed by a single layer, and when the cap layer 26 is formed by a single layer of an organic film, the cap layer 26 may be formed by a film containing aromatic hydrocarbon. Note that the aromatic hydrocarbon in the film containing the aromatic hydrocarbon may be N,N′-di-1-naphthyl-N,N′-diphenylbenzidine (also referred to as α-NPD or NPB). On the other hand, when the cap layer 26 is formed by a single layer of an inorganic film, the cap layer 26 may be formed by a LiF film. Furthermore, the cap layer 26 may be formed by a layered body of an organic film and an inorganic film. When the cap layer 26 is formed by the layered body of the organic film and the inorganic film, the organic film may be the film containing the aromatic hydrocarbon, and the inorganic film may be the LiF film.
Further, as in the present embodiment, when the cap layer 26 is formed by the layered body of the organic film and the inorganic film, a refractive index of the organic film in a visible light region is preferably higher than a refractive index of the inorganic film in the visible light region, and it is more preferable that the refractive index of the organic film in the visible light region be from 1.8 to 2.1, and the refractive index of the inorganic film in the visible light region be from 1.2 to 1.3.
Further, when the cap layer 26 is formed by the layered body of the organic film and the inorganic film, the film thickness of the organic film is preferably greater than the film thickness of the inorganic film, and it is more preferable that the film thickness of the organic film be from 50 nm to 100 nm, and the film thickness of the inorganic film be from 10 nm to 30 nm.
In the display device 1 according to the present embodiment, as illustrated in (b) of
When it is not necessary to expose the portion of the extending portion 25′ in consideration of the electrical connection with the drive circuit 50 and the like, the cap layer 26 may be formed overlapping all of the second electrode 25 including the extending portion 25′, as in the active matrix substrate 40′ illustrated in
Next, a description will be given of a second embodiment of the present invention with reference to
(a) of
Even when using the mask 31 illustrated in
In the mask 31, for example, contaminants such as dust or cleaning liquid for the mask may become adhered to or remain in a portion at which the hauling sheet 31H overlaps the mask opening FK, which is a through-hole in the mask sheet 31S, in the same manner as in the mask recess HK, which is the non-through-hole in the mask 30 illustrated in
In the mask 31, the portion at which the hawling sheet 31H overlaps the mask opening FK, which is the through-hole in the mask sheet 31S, that is, a portion corresponding to the mask recess HK, which is the non-through-hole in the mask 30 illustrated in
In the mask 31, in a portion of the active matrix substrate facing a portion of the mask 31 other than the portion at which the hauling sheet 31H overlaps the mask opening FK, which is the through-hole in the mask sheet 31S, it is not necessary to form the cap layer 26 to cover the extending portion 25′.
(a) of
As illustrated in (a) of
As illustrated in (a) of
In the mask 32, in a portion of the active matrix substrate facing a portion of the mask 32 other than the portion in which the mask recesses HK, which are the non-through-holes, are formed, it is not necessary to form the cap layer 26 to cover the extending portion 25′.
As illustrated in
Further, the extending portion 25′ includes second notched regions RGP formed corresponding to corner portions of the display region DA. The cap layer 26 is formed covering the second notched regions RGP of the extending portion 25′.
In the active matrix substrate 41, the cap layer 26 does not cover the extending portion 25′ in regions other than the first notched region KGP of the extending portion 25′ and the second notched regions RGP of the extending portion 25′.
(a) of
As illustrated in (a) of
In the present embodiment, the cap layer 26 covers all of the first notched region KGP of the extending portion 25′ and the four second notched regions RGP of the extending portion 25′, but no such limitation is intended, and the cap layer 26 may cover only the first notched region KGP of the extending portion 25′, or may cover only one or more of the four second notched regions RGP of the extending portion 25′.
A display device includes a display region in which a plurality of light-emitting elements are disposed, a frame region surrounding the display region, and a sealing layer, each of the light-emitting elements being provided with a first electrode, a second electrode formed above the first electrode, and a function layer formed between the first electrode and the second electrode. The second electrode includes an extending portion extending from the display region to the frame region, and overlaps all of the display region. A cap layer is provided above the extending portion to overlap at least part of an end portion of the extending portion, and the cap layer overlaps all of the display region. The sealing layer overlaps all of the second electrode and all of the cap layer.
In the display device according to the first aspect, a notched portion is provided in the display region, the extending portion includes a first notched region formed along the notched portion, and the cap layer is formed covering all of the first notched region.
In the display device according to the first or second aspect, the extending portion includes a second notched region formed corresponding to a corner portion of the display region, and the cap layer is formed covering at least part of the second notched region.
In the display device according to any one of the first to third aspects, the cap layer overlaps all of the second electrode including the extending portion.
The display device according to any one of the first to third aspects includes a drive circuit configured to drive the plurality of light-emitting elements. On a side, which is a side of the drive circuit, of the extending portion, the end portion of the extending portion is positioned closer to the drive circuit than an end portion of the cap layer.
The display device according to any one of the first to fifth aspects, the cap layer is an inorganic film.
In the display device according to the sixth aspect, the inorganic film is a LiF film.
The display device according to any one of the first to fifth aspects, the cap layer is an organic film.
In the display device according to the eighth aspect, the organic film is a film containing an aromatic hydrocarbon.
The display device according to any one of the first to fifth aspects, the cap layer is a layered body of an organic film and an inorganic film.
In the display device according to the tenth aspect, the organic film is a film containing an aromatic hydrocarbon, and the inorganic film is a LiF film.
In the display device according to the tenth or eleventh aspect, a refractive index of the organic film in a visible light region is greater than a refractive index of the inorganic film in the visible light region.
In the display device according to the twelfth aspect, the refractive index of the organic film in the visible light region is from 1.8 to 2.1, and the refractive index of the inorganic film in the visible light region is from 1.2 to 1.3.
In the display device according to any one of the tenth to thirteenth aspect, a film thickness of the organic film is greater than a film thickness of the inorganic film.
In the display device according to the fourteenth aspect, the film thickness of the organic film is from 50 nm to 100 nm, and the film thickness of the inorganic film is from 10 nm to 30 nm.
The present invention is not limited to each of the embodiments described above, and various modifications may be made within the scope of the claims. Embodiments obtained by appropriately combining technical approaches disclosed in each of the different embodiments also fall within the technical scope of the present invention. Furthermore, novel technical features can be formed by combining the technical approaches disclosed in the embodiments.
The present invention can be utilized for a display device.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2018/036060 | 9/27/2018 | WO | 00 |