JP4600786B2 - Display device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a top emission type display device and a manufacturing method thereof.

  In recent years, attention has been paid to an organic EL display device that displays an image using an organic EL (Electro Luminescence) phenomenon as one of flat panel displays. This organic EL display device has excellent features such as a wide viewing angle and low power consumption because it utilizes the light emission phenomenon of the organic EL element itself. Furthermore, since this organic EL display device exhibits high responsiveness to high-definition high-speed video signals, development for practical use is being promoted particularly in the video field. Further, such an organic EL display device has been attracting attention as a device having flexibility by using a plastic substrate as a substrate in order to utilize the flexibility inherent in the organic light emitting material.

  Of the driving methods used in organic EL display devices, the active matrix method using thin film transistors (TFTs) as driving elements is superior in terms of responsiveness and resolving power compared to the passive matrix method. The organic EL display device is considered to be a particularly suitable driving method. This active matrix type organic EL display device has a drive panel in which an organic EL element including an organic light emitting layer and a drive element (the above-described thin film transistor) for driving the organic EL display element are disposed. The drive panel and the sealing panel are bonded to each other with an adhesive layer so as to sandwich the organic EL element. Moreover, the organic EL element has a configuration in which an organic light emitting layer is formed between a pair of electrodes.

  The organic EL display device has a bottom emission method that emits light from each organic EL element toward the drive panel, and a top emission that emits this light toward the sealing panel. ), But the latter is the mainstream of development because the aperture ratio can be increased.

  Here, in the organic EL display device of the top emission type, the light extraction side, that is, the electrode on the sealing panel side is an electrode common to each organic EL element, and for example, ITO (IndiumTin Oxide) or the like It is made of a light transmissive conductive material. However, such a light-transmitting conductive material has a resistivity about two to three digits higher than that of a normal metal material. Therefore, the voltage applied to the light extraction side electrode becomes non-uniform in the plane, and thus there is a problem that the light emission luminance between the organic EL elements varies in position and the display quality is deteriorated.

  Therefore, for example, Patent Document 1 discloses a technique in which auxiliary wiring for connecting to the light extraction side electrode is formed of the same material in the same layer as the driving panel side electrode.

JP 2002-318556 A

  Thus, if the auxiliary wiring is formed of a material having a lower resistivity than the light extraction side electrode and is connected to the light extraction side electrode, the above-described in-plane non-uniformity of the electrode voltage is to some extent. It is thought to be alleviated.

  However, in the technique of the above-mentioned Patent Document 1, when, for example, aluminum (Al) or an Al alloy is used for the surface of the electrode on the drive panel side, if the auxiliary wiring is formed of the same material as the electrode, the surface of the auxiliary wiring is It becomes easy to be oxidized. When the surface is oxidized, the connection resistance between the auxiliary wiring and the light extraction side electrode increases, and a large voltage drop occurs in this portion. Therefore, due to this increase in voltage drop, the power consumption of the device also increases.

  As described above, in the conventional technology, it is difficult to improve the display quality by preventing the increase in power consumption regardless of the configuration of the auxiliary wiring and realizing the in-plane uniformity of the electrode voltage on the light extraction side. there were.

  The present invention has been made in view of such problems, and an object thereof is to provide a display device capable of ensuring low power consumption and improving display quality regardless of the configuration of the auxiliary wiring, and a method for manufacturing the same. There is to do.

The display device according to the present invention includes a wiring layer electrically connected to the driving element and the driven element of the multiple, the laminated structure of a plurality of conductive layers with formed of the same layer as the wiring layer, a plurality The lowermost titanium (Ti) layer of the conductive layer covers the contact portion having a wider portion than the width of the other conductive layers , the drive element and the wiring layer, and in a region corresponding to the contact portion. A flattened insulating film having an opening with a side surface with a forward taper shape that is wide at the top and narrow at the bottom , and aluminum or an alloy containing aluminum as a main component, and is provided in a grid-like planar shape on the flattened insulating film with a pendent portion in the opening of the planarization insulating film, the auxiliary wiring overhanging portion is in contact with the uppermost conductive layer of the contact portion, an alloy mainly composed of aluminum or aluminum Ri is constructed, arranged and a plurality of first electrodes formed in correspondence with the respective drive element in the lattice of the auxiliary wiring on the planarization insulating film, in a region between the plurality of first electrodes on the planarization insulating film together is, having an opening communicating with the opening of the planarization insulating film, opening the inter-electrode insulating film having a side surface of the narrow forward tapered shape under a wide top and having a width greater than the opening of the planarization insulating film a plurality of light emitting portions formed respectively on the first electrode, the plurality of light emitting portions while being formed by a material capable of transmitting light from the light emitting portion, the inter-electrode insulating film, the opening of the insulating film And a common second electrode that is provided in the opening of the planarization insulating film and is in direct contact with the widened portion of the lowermost conductive layer of the contact portion within the opening of the planarization insulating film. Has a film containing an insulating film and a metal film formed on the drive element side. Those which are.

In the display device of the present invention, since the second electrode and the auxiliary wiring are electrically connected through the conductive contact portion, even if the surface of the auxiliary wiring is oxidized, the connection resistance is increased. Avoided. In addition, the widened portion of the lowermost conductive layer of the plurality of conductive layers of the contact portion has a structure in direct contact with the second electrode, and the upper conductive layer is naturally in the atmosphere. Even if oxidized and good electrical connection with the light extraction side electrode (second electrode) is not possible, good electrical connection is made between the widened portion of the lowermost conductive layer and the light extraction side electrode. Secured. In addition, since a film including an insulating film and a metal film formed on the drive element side is formed below the contact portion, the contact resistance becomes low resistance, and resistance increase due to disconnection or the like hardly occurs.

Method of manufacturing a display device according to the present invention includes the steps of electrically connecting the wiring layer and the plurality of driving elements to form a plurality of driving elements and wiring layers on the base plate, the same wiring layer The contact portion having a laminated structure of a plurality of conductive layers is formed by the layer, and a widened portion wider than the width of the other conductive layers is formed on the lowermost titanium (Ti) layer of the plurality of conductive layers. a step of providing, to form a planarizing insulating film covering the driving element and the wiring layers, in a region corresponding to the contact portion of the planarization insulating film, a step of providing an opening in which the lower wide top has a side surface of the narrow forward tapered shape An auxiliary wiring made of aluminum or an alloy containing aluminum as a main component is formed on the planarizing insulating film in a grid-like planar shape, and a protruding portion is provided in the opening of the planarizing insulating film, and the protruding portion is contacted Best part A plurality of first electrodes made of aluminum or an alloy containing aluminum as a main component corresponding to the plurality of driving elements in the lattice of the auxiliary wiring on the planarization insulating film at the same time as being in contact with the conductive layer of the layer forming a, the inter-electrode insulating film is formed in a region between the plurality of first electrodes on the planarization insulating film, the inter-electrode insulating film, the opening communicating with the opening of the planarization insulating film is provided, the opening The width of the flattened insulating film wider than the opening of the planarization insulating film , the step of providing a forward tapered side surface having a wide top and a narrow bottom, a step of forming a light emitting portion on each of the first electrodes , a plurality of light emitting portions, On the interelectrode insulating film, in the opening of the interelectrode insulating film and in the opening of the planarizing insulating film, the second electrode is formed in common by a material that can transmit light from each light emitting portion, and the second electrode is Conduction of the bottom layer of the contact part within the opening of the planarization insulating film And a step of direct contact with the widened portion of the sexual layer, in the step of forming the contact portion, and the lowermost titanium (Ti) layer, an aluminum middle layer (Al) layer, the top layer of molybdenum (Mo) layer After forming a mask on the uppermost layer, the intermediate layer is selectively removed by wet etching using the mask, and the lowermost layer is selectively removed by dry etching using the mask. After that, the second electrode is formed so as to cover the lowermost layer, the intermediate layer, and the uppermost layer.

  According to the display device or the manufacturing method of the display device of the present invention, since the second electrode and the auxiliary wiring are electrically connected via the conductive contact portion, the surface of the auxiliary wiring is temporarily oxidized. Even so, an increase in connection resistance can be avoided. Therefore, it is possible to ensure low power consumption and improve display quality regardless of the configuration of the auxiliary wiring.

In addition, since the widened portion of the lowermost conductive layer of the contact portion is directly electrically connected to the second electrode, the upper conductive layer spontaneously oxidizes in the atmosphere to extract light. Even if good electrical connection with the side electrode (second electrode) cannot be achieved , good electrical connection is ensured between the widened portion of the lowermost conductive layer and the light extraction side electrode.

  Furthermore, if the wiring layer on the driving element side is arranged under the contact portion, the step due to the planarization layer is reduced, the contact resistance is reduced, and the contact resistance is not increased. Thus, the yield can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 shows a configuration of a display device (organic EL display device) according to a first embodiment of the present invention. The organic EL display device 1 is used as an extremely thin organic EL color display device or the like. For example, a display in which a plurality of organic EL elements EL described later are arranged in a matrix on a transparent substrate 10A. A region 110 is formed, and a signal line driving circuit 120 and a scanning line driving circuit 130 which are drivers for displaying images are formed around the display region 110.

  A pixel drive circuit 140 is formed in the display area 110. FIG. 2 illustrates an example of the pixel driving circuit 140. The pixel driving circuit 140 is formed below a first electrode 18A described later, and includes a driving transistor Tr1 and a writing transistor Tr2, a capacitor (holding capacitor) Cs therebetween, a first power supply line (Vcc), and a second power source line (Vcc). This is an active drive circuit having an organic EL element EL connected in series to the drive transistor Tr1 between power supply lines (GND). The driving transistor Tr1 and the writing transistor Tr2 are configured by a general thin film transistor (TFT (Thin Film Transistor)), and the configuration may be, for example, an inverted staggered structure (so-called bottom gate type) or a staggered structure (top gate type). There is no particular limitation.

  In the pixel driving circuit 140, a plurality of signal lines 120A are arranged in the column direction, and a plurality of scanning lines 130A are arranged in the row direction. The intersection of each signal line 120A and each scanning line 130A corresponds to one of the organic EL elements EL (sub pixel). Each signal line 120A is connected to the signal line drive circuit 120, and an image signal is supplied from the signal line drive circuit 120 to the source electrode of the write transistor Tr2 via the signal line 120A. Each scanning line 130A is connected to the scanning line driving circuit 130, and a scanning signal is sequentially supplied from the scanning line driving circuit 130 to the gate electrode of the writing transistor Tr2 via the scanning line 130A.

  FIG. 3 shows a planar configuration of the display region 110 of the organic EL display device 1, and FIG. 4 shows a cross-sectional configuration along the line IV-IV in FIG.

  This organic EL display device 1 has a laminated structure in which a multilayer film is laminated between a pair of insulating transparent substrates 10A and 10B. Specifically, the gate electrode 11, the gate insulating film 12, the silicon film 13A, the stopper insulating film 14, the n + amorphous silicon film 13B, and the wiring layer 15A (source / drain electrodes) are laminated from the transparent substrate 10A side, and the thin film transistor Tr is comprised. In addition, an insulating protective insulating film (passivation film) 16 and a planarizing insulating film 17A are stacked on the thin film transistor Tr. On the planarization insulating film 17A, an organic EL element EL is formed corresponding to the formation region of the thin film transistor Tr.

  The transparent substrates 10A and 10B are made of an insulating material such as a glass material or a plastic material.

  The thin film transistor Tr is a drive element for driving each organic EL element EL to emit light. Of these, the gate electrode 11 is made of, for example, molybdenum (Mo). Further, the silicon film 13A is a part for forming a channel region of the thin film transistor Tr, and is formed of, for example, an amorphous silicon film.

  The wiring layer 15A constitutes a source electrode and a drain electrode of the thin film transistor Tr and also has a function as a wiring such as a signal line. As a constituent material of the wiring layer 15A, for example, titanium (Ti), titanium nitride (TiN), Al, Mo, tungsten (W), chromium (Cr), gold (Au), platinum (Pt), copper (Cu) ITO, IZO (Indium Zinc Oxide; Indium Zinc Oxide) or silver (Ag), or an alloy containing these metal materials as a main component.

  The wiring layer 15A has a laminated structure such as Mo / Al / Ti, Mo / (AlSi alloy) / Ti, Mo / (AlSiCu alloy) / Ti, or Mo / (AlCe (cerium) alloy) / Ti. You may have.

  The protective insulating film 16 is for protecting the thin film transistor Tr, and is made of, for example, an insulating material made of at least one of SiO2, SiN, or SiON. The planarization insulating film 17A is for planarizing the layer structure to form the organic EL element EL thereon. For example, a photosensitive polyimide resin, polybenzoxazole resin, novolac resin, polyhydroxystyrene, It is made of an insulating material such as acrylic resin.

  Each organic EL element EL has a stacked structure in which the first electrode 18A, the organic light emitting layer 19 and the second electrode 20 are stacked in this order from the planarization insulating film 17A side. Among these, the first electrode 18A and the organic light emitting layer 19 are separated from each other by the interelectrode insulating film 21 on the planarizing insulating film 17A, and are formed in a matrix shape in the transparent substrates 10A and 10B, for example, in a rectangular shape as shown in FIG. Is arranged. On the other hand, the second electrode 20 is a common electrode for each organic EL element EL, and is uniformly formed in the transparent substrates 10A and 10B as shown in FIG.

  The first electrode 18A is an electrode (anode electrode or cathode electrode) for applying a voltage to the organic light emitting layer 19, and also serves as a reflective electrode for reflecting light from the organic light emitting layer 19 and guiding it upward. It is functioning. Therefore, the first electrode 18A is made of a highly reflective metal, for example, Al, an alloy mainly containing Al, such as an AlNd (neodymium) alloy or an AlCe alloy. Note that such a constituent material of the first electrode 18A has a property that the surface is easily oxidized (surface oxidation property).

  The organic light emitting layer 19 is formed by sequentially depositing a hole transport layer, a light emitting layer, and an electron transport layer (not shown), and is sandwiched between the first electrode 18A and the second electrode 20. When a predetermined voltage is applied between the first electrode 18A and the second electrode 20, light emission can be obtained by carrier recombination of holes and electrons injected into the light emitting layer.

  The second electrode 20 is also an electrode (an anode electrode or a cathode electrode) for applying a voltage to the organic light emitting layer 19. Since the second electrode 20 transmits light from the organic light emitting layer 19 and emits the light upward, it is a transparent or translucent electrode. Therefore, the second electrode 20 is made of, for example, ITO or IZO, which is a transparent material, or MgAg alloy, Cu, Ag, Mg, Al, or the like, which is a translucent material.

  As shown in FIGS. 3 and 4, the auxiliary wiring 18B is formed in the same layer as the first electrode 18A in the region between the first electrodes 18A. The auxiliary wiring 18 </ b> B is for electrically connecting the second electrode 20 to suppress in-plane non-uniformity of the electrode voltage in the transparent second electrode 20 having high resistance. Therefore, the auxiliary wiring 18B is configured to have a resistance lower than that of the second electrode 20 (for example, a material having a low resistivity). Specifically, the auxiliary wiring 18B is made of the same material as that of the first electrode 18A described above. Consists of.

  Further, the planarizing insulating film 17A and the interelectrode insulating film 21 are provided with forward tapered openings in a part of the formation region of the auxiliary wiring 18B (see FIG. 4). A conductive contact portion 15B is formed between the bottom of the opening and the gate insulating film 12, and the second electrode 20 and the auxiliary wiring 18B are electrically connected on the contact portion 15B.

  For example, the contact portion 15B is formed in the same layer as the wiring layer 15A and is made of the same material as the wiring layer 15A. Specifically, the constituent material of the contact portion 15B is, for example, titanium (Ti), titanium nitride (TiN), Al, Mo, tungsten (W), chromium (Cr), gold (like the wiring layer 15A). Au), platinum (Pt), copper (Cu), ITO, IZO (Indium Zinc Oxide; indium zinc oxide) or silver (Ag), or alloys containing these metal materials as main components. However, the contact portion 15 </ b> B is not limited to these, and is configured to include a part of a conductive material in which the surface is not easily oxidized and a good connection (preferably ohmic connection) can be established with the second electrode 20. Just do it.

  As shown in FIG. 5 in an enlarged manner, the contact portion 15B has a laminated structure of two or more conductive layers. In this embodiment, for example, the lowermost Ti (titanium) layer 15B1 (first conductive layer) and The intermediate layer 15B2 (second conductive layer) and the uppermost Mo (molybdenum) layer 15B3 (third conductive layer) have a three-layer structure. The Ti layer 15B1 is wider than the Al layer 15B2 and the Mo layer 15B3, and the second electrode 20 and the Ti layer 15B1 are in direct contact with each other at the widened portion W. Thereby, in this organic EL display device 1, good electrical connection is established between the auxiliary wiring 18B and the second electrode 20 through the Ti layer 15B1, which is the lowermost layer of the contact portion 15B, and low power consumption is ensured. At the same time, the display quality can be improved.

  Of the plurality of conductive layers constituting the contact portion 15B, the lowermost conductive layer (here, the lower Ti layer 15B1) is made of a material having high etching selectivity with respect to the first electrode 18A. It is preferable. This is because the Ti layer 15B1 is not lost by etching when the first electrode 18A is formed in the manufacturing process described later. The intermediate Al layer 15B2 may be made of an AlSi alloy, an AlSiCu alloy, or an AlCe (cerium) alloy. Further, the uppermost Mo layer 15B3 exists only in a portion where the auxiliary wiring 18B is present in the contact portion 15B, and a portion where the auxiliary wiring 18B is not present disappears when the auxiliary wiring 18B is etched in the manufacturing process described later. Yes.

  The side surface of the opening of the interelectrode insulating film 21 has a forward taper shape with a wide top and a narrow bottom. Here, the forward tapered shape is desirably as gentle as possible. In addition, the width of the opening between the interelectrode insulating films 21 is configured to be wider than the opening in the planarizing insulating film 17A where the contact portion 15B is formed, and as shown in FIG. The electrode 20 has a forward tapered shape or a stepped shape in which the upper portion is wide and the lower portion is narrow in these opening portions. As described in detail later, the forward taper shape is made as gentle as possible or the opening is formed in a staircase shape as will be described in detail later. However, this may cause disconnection or increase in resistance when the second electrode 20 is formed. This is to avoid the problem. The interelectrode insulating film 21 is made of an insulating material such as a photosensitive polyimide resin.

  A protective film (not shown) is uniformly formed on the second electrode 20 of such an organic EL element EL, and sealing is provided between the protective film (not shown) and the transparent substrate 10B. Resin 17B is uniformly formed. With such a configuration, the organic EL display device 1 finally emits the light emitted from the organic light emitting layer 19 from the second electrode 20 side (transparent substrate 10B side), that is, from above. It has a so-called top emission type structure.

  A protective film (not shown) on the second electrode 20 is for protecting the second electrode 20, and is made of, for example, an insulating material made of at least one of SiO2, SiN, or SiON. The sealing resin 17B is for flattening the layer structure and sandwiching it between the transparent substrates 10B.

  Here, the thin film transistor Tr corresponds to a specific example of “driving element” in the present invention, and the organic light emitting layer 19 corresponds to a specific example of “light emitting portion” in the present invention. Further, the planarization insulating film 17A and the interelectrode insulating film 21 correspond to a specific example of “insulating layer” in the present invention.

  Next, a method for manufacturing the organic EL display device 1 will be described with reference to FIGS. 6 to 9 are sectional views showing a part of the manufacturing process of the organic EL display device 1.

  First, as shown in FIG. 6, the transparent substrate 10 </ b> A made of the above-described material is made of the above-described material using, for example, a sputtering method, a CVD (Chemical Vapor Deposition) method, and a photolithography method. Gate electrode 11 having a thickness of 100 nm, gate insulating film 12 having a thickness of 400 nm, silicon film 13A having a thickness of 30 nm, stopper insulating film 14 having a thickness of 300 nm, n + amorphous silicon film 13B having a thickness of 100 nm and 600 nm. The wiring layers 15A are stacked in this order, and a plurality of thin film transistors Tr having a matrix shape, for example, are formed.

  Here, when the wiring layer 15A is formed by, for example, a sputtering method, the contact portion 15B is formed at the same time in the same stacked structure as the wiring layer 15A using the same material as the wiring layer 15A. The contact portion 15B is formed on the gate insulating film 12, that is, on the same layer as the wiring layer 15A, and between the first electrodes 18A as shown in FIG.

  That is, as shown in FIG. 7A, on the gate insulating film 12, for example, a Ti layer 15B1 (film thickness of 50 nm), an Al layer 15B2 (film thickness of 500 nm), and a Mo layer 15B3 (film thickness of 50 nm) are sputtered in this order. 7B, the Mo layer 15B3 is formed by wet etching using, for example, a mixed acid of phosphoric acid, nitric acid and acetic acid (phosphoric acid nitric acid) using the photoresist film PH as a mask. And the Al layer 15B2 is selectively removed. Subsequently, as shown in FIG. 7C, the Ti layer 15B1 is selectively removed by dry etching using, for example, chlorine gas, and a part of the surface of the Ti layer 15B1 is exposed as shown in FIG. Thus, the widened portion W is formed. After that, the photoresist film PH is peeled off. As a result, the contact portion 15B can be formed in the same layer as the wiring layer 15A.

  In this embodiment, after the photolithography process, the Al layer 15B2 is wet-etched using phosphoric acid nitric acid as an etchant, and then the Ti layer 15B1 is dry-etched using chlorine gas. Since 15B is formed, it is possible to suppress the occurrence of pattern defect defects due to etching.

  That is, in this embodiment, it is possible to reduce pattern defects caused by dry etching while maintaining the advantage of dry etching that the difference between the line width of the photoresist pattern and the pattern line width after etching is small. The lowermost Ti layer 15B1 is processed by dry etching, whereas the upper Al layer 15B2 and Mo layer 15B3 are processed by wet etching, so that the Ti line width naturally becomes a shape that protrudes wider than the Al line width. The Al layer 15B2 spontaneously oxidizes in the atmosphere, and good electrical connection with the light extraction side electrode (second electrode 20) cannot be made, but it is good between the lowermost Ti layer 15B1 and the light extraction side electrode. Electrical connection can be obtained.

  Incidentally, for example, when a wet etching process is applied to a Ti / Al / Ti laminated structure (see Comparative Example 2 described later), the etching rate of Ti and Al is greatly different from that of the upper Ti layer. When the etching rate of Al is faster, the end of the upper layer Ti becomes unstable and may break and become a foreign material, causing a pattern defect.

  After forming the thin film transistor Tr and the contact portion 15B, as shown in FIG. 8A, the protective insulating film 16 made of the above-described material is uniformly formed on the thin film transistor Tr and the contact portion 15B by, for example, the CVD method. Form. Subsequently, a planarization insulating film 17A made of the above-described material is uniformly applied and formed on the protective insulating film 16 by, for example, a spin coating method or a slit coating method. Then, the region corresponding to the contact portion 15B is exposed and developed by, for example, a photolithography method to form an opening, and then baked to thereby have an opening having a forward tapered side surface as indicated by reference numeral P1 in the drawing. Form. At this time, as the photosensitive resin used as the planarization insulating film 17A, a photosensitive resin that makes the inclination as gentle as possible is appropriately selected. In order to make this inclination more gradual, an opening is formed using a multi-tone mask such as a halftone mask or a gray tone mask, or a plurality of masks having different opening sizes are used. A plurality of exposure processes may be performed. The inclination of the forward taper shape is appropriately set depending on the film thickness and formation method of the second electrode 20 to be formed later.

  After providing an opening in the planarization insulating film 17A, as shown in FIG. 8B, on the planarization insulating film 17A and the contact portion 15B, for example, the constituent materials (for example, the first electrode 18A and the auxiliary wiring 18B described above). In this example, the metal layer 18 is uniformly formed with a thickness of, for example, about 300 nm using, for example, a sputtering method using a metal material.

  After the metal layer 18 is formed, as shown in FIG. 8C, the metal layer 18 is selectively etched by, for example, a photolithography method, so that the first having the shape shown in FIGS. Electrode 18A and auxiliary wiring 18B are formed respectively. At this time, the first electrode 18A is formed at a position corresponding to each thin film transistor Tr, and the auxiliary wiring 18B is formed in a region between the first electrodes 18A. Further, the auxiliary wiring 18B is patterned so that a part thereof is electrically connected to the contact portion 15B. Here, the contact portion 15B is not necessarily a material having a high etching selectivity with respect to the metal layer 18 as described above, but only a conductive material may have an etching selectivity, and the metal layer 18 is etched. At this time, there is no possibility that the conductive material of the contact portion 15B is etched together. Note that etching at this time is appropriately selected.

  After forming the first electrode 18A and the auxiliary wiring 18B, as shown in FIG. 9A, the interelectrode insulating film made of the above-described material is formed on the planarizing insulating film 17A, the first electrode 18A, and the auxiliary wiring 18B. 21 is uniformly coated and formed by, for example, spin coating or slit coating, and a predetermined shape, for example, each first electrode 18A and each organic light emitting layer 19 to be formed later are separated from each other by, for example, photolithography. Pattern. Also at this time, the region corresponding to the contact portion 15B is selectively removed by, for example, photolithography to form an opening having a forward tapered side surface as indicated by reference numeral P2 in the drawing. Similarly, in order to make the inclination as gentle as possible, an opening is formed using a multi-tone mask such as a halftone mask or a gray tone mask, or a plurality of masks having different opening sizes are used. A plurality of exposure processes are performed. In addition, the width of the opening between the interelectrode insulating films 21 is formed so as to have a forward tapered shape in which the top is wide and the bottom is narrow.

  After the interelectrode insulating film 21 is formed, as shown in FIG. 9B, the organic light emitting layer 19 is formed on each first electrode 18A by, for example, a vacuum evaporation method. Then, on the organic light emitting layer 19, the interelectrode insulating film 21, the planarizing insulating film 17A, the contact portion 15B, and the auxiliary wiring 18B, the second electrode 20 made of the above-described material, for example, by a vacuum deposition method is formed to a thickness of, for example, about 10 nm. It forms uniformly.

  Finally, after uniformly forming a protective film (not shown) made of the above-described material on the second electrode 20 by, for example, a CVD method, a sealing resin 17B is formed on the protective film (not shown). For example, the organic EL display device 1 according to the present embodiment shown in FIGS. 3 and 4 is manufactured by forming it uniformly by the dropping injection method and sandwiching it between the transparent substrates 10B made of the above-described materials.

  In the organic EL display device 1, when a voltage is applied to the first electrode 18 </ b> A via the wiring layer 15 </ b> A and the thin film transistor Tr, the organic light emitting layer 19 emits light with a luminance corresponding to the potential difference with the second electrode 20. . The light from the organic light emitting layer 19 passes through the second electrode while being reflected by the first electrode 18A, and is emitted upward in FIG. 4, that is, toward the transparent substrate 10B. A predetermined image is displayed on the organic EL display device 1 by emitting light corresponding to the pixel signal from the organic EL element EL arranged in each pixel.

  Here, in the organic EL display device 1, the second electrode 20 and the auxiliary wiring 18 </ b> B are not easily oxidized on the surface, and can be connected to the second electrode 20 (preferably ohmic connection). Even if the surface of the auxiliary wiring 18B made of the same material as that of the first electrode 18A is oxidized, the surface between the second electrode 20 and the auxiliary wiring 18B is electrically connected through the conductive contact portion 15B. An increase in the connection resistance is avoided. Specifically, as shown in FIG. 4, the electrical connection path P includes the second electrode 20 → the widened portion W of the lowermost Ti layer 15 </ b> B <b> 1 → the intermediate Al layer 15 </ b> B <b> 2 → the uppermost Mo layer. 15B3 → auxiliary wiring 18B.

  For example, in the conventional organic EL display device 101 (Comparative Example 1) shown in FIG. 10, the auxiliary wiring 118B is formed of the same material in the same layer as the first electrode 118A and is directly connected to the second electrode 120. Therefore, when the surface of the auxiliary wiring 118B is oxidized, the connection resistance between the second electrode 120 and the auxiliary wiring 118B increases.

  In the organic EL display device 1 of the present embodiment, the auxiliary wiring 18B is formed in the same layer as the first electrode 18A, and only a part of the auxiliary wiring 18B located in the region between the first electrodes 18A. Is connected to the contact portion 15B of the same layer as the wiring layer 15A, there is no possibility that the thin film transistor Tr or the wiring layer 15A may restrict the layout when the contact portion 15B is formed.

  As described above, in the present embodiment, the second electrode 20 and the auxiliary wiring 18B are electrically connected via the conductive contact portion 15B, and only a part of the auxiliary wiring 18B is connected to the contact portion. Since the connection is made with 15B, an increase in connection resistance can be avoided even if the surface of the auxiliary wiring 18B is oxidized, and there is no restriction on the layout when the contact portion 15B is formed. Therefore, it is possible to improve the display quality of the organic EL display device 1 while ensuring the freedom in layout and low power consumption.

  Further, since there is no restriction on the layout when forming the contact portion 15B, there is no short circuit between the wiring layer 15A and the like due to an unreasonable layout, compared with a conventional organic EL display device. Thus, the production yield can be improved.

  Furthermore, since the contact portion 15B is formed of the same material in the same layer as the wiring layer 15A, the formation of the contact portion 15B does not increase the number of manufacturing steps, and the manufacturing cost can be maintained. That is, since the wiring layer 15A and the contact part 15B can be formed in the same process, the manufacturing process can be simplified.

  In addition, since the contact portion 15B is formed of a material having a high etching selectivity with respect to the first electrode 18A, when the metal layer 18 is etched to form the first electrode 18A and the auxiliary wiring 18B, There is no risk of etching the contact portion 15B together. Therefore, the contact portion 15B as described above can be reliably formed.

  Furthermore, the side surfaces of the openings in the planarization insulating film 17A and the interelectrode insulating film 21 are formed in a forward taper shape having a wide top and a narrow bottom. It is possible to avoid an increase in value and to avoid a decrease in manufacturing yield due to this.

  In addition, in the present embodiment, the contact portion 15B includes the lowermost Ti (titanium) layer 15B1 (first conductive layer), the intermediate Al layer 15B2 (second conductive layer), and the uppermost Mo layer. The Ti layer 15B1 has a widened portion W wider than the Al layer 15B2 and the Mo layer 15B3, and the second electrode 20 and the Ti layer 15B1 are in direct contact with each other. Therefore, the intermediate layer Al layer 15B2 is naturally oxidized in the atmosphere, and a good electrical connection cannot be made with the light extraction side electrode (second electrode 20), but the lowermost Ti layer 15B1 and the light extraction side electrode Good electrical connection is ensured between and.

  Further, when forming the contact portion 15B, the Mo layer 15B3 and the Al layer 15B2 are wet-etched using phosphoric acid nitric acid as an etchant, and then the Ti layer 15B1 is dry-etched using chlorine gas. Therefore, it is possible to reduce pattern defects caused by dry etching while leaving the advantage of dry etching that the difference between the line width of the photoresist pattern and the pattern line width after etching is small. Details will be described later.

[Second Embodiment]
Next, a display device according to a second embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the component same as the component in 1st Embodiment, and description is abbreviate | omitted suitably.

  FIG. 11 illustrates a cross-sectional configuration of the contact portion 25B in the display device (organic EL display device) according to the present embodiment. In the present embodiment, a low resistance wiring material layer 26 that is the same layer as the source signal line or gate wiring connected to the thin film transistor Tr is formed on the transparent substrate 11A below the contact portion 25B. The low-resistance wiring material layer 26 has a film thickness of, for example, 500 nm, on which the same layer as the gate electrode 11, the gate insulating layer 12, the silicon film 13A, the stopper insulating film 14, and the n + amorphous silicon film 13B. Are stacked in this order. The low resistance wiring material layer 26 is necessary to prevent the resistance from increasing in proportion to the length of the gate wiring, the source signal line, and the current supply line as the display has a larger screen and higher definition. is there. The low resistance wiring material layer 26 is not included in the first embodiment (FIG. 5) because it is not necessary in the thin film transistor Tr portion. The configuration other than the portion relating to the thin film transistor Tr and the protective insulating film 16 is the same as in the first embodiment.

  In the present embodiment, since a film such as the low-resistance wiring material layer 26 is present below the contact portion 25B, the distance between the first electrode 18B and the second electrode 20 is shortened, so that the level difference caused by the planarization film And the contact resistance is lower than that of the first embodiment. Also, resistance increase due to disconnection or the like is less likely to occur. Other functions and effects are the same as those of the first embodiment.

  Hereinafter, the evaluation of the contact resistance at the contact portions 15B and 25B of the first and second embodiments will be described in comparison with that of the structure of the comparative example 2 shown in FIG.

(Comparative Example 2)
FIG. 12 shows the structure of the contact portion 115B of the comparative example 2 corresponding to the contact portion 15B of FIG. The wiring layer 115A and the contact portion 115B have a three-layer structure of Ti layer 115B3 (film thickness 50 nm) / Al layer 115B2 (film thickness 500 nm) / Ti layer 115B1 (film thickness 50 nm). The second electrode 120 is disposed on the protective insulating film 116 and the planarization insulating film 117A so as to be electrically connected to the upper Ti layer 115B3. Other structures are the same as those in the above embodiment.

  Incidentally, the structure of Comparative Example 2 is included in a prior application (Japanese Patent Application No. 2006-168906, filing date 2006.6.19) by the same applicant as the present applicant. In this prior application, in order to increase the reflectivity of the electrode on the drive panel side and reduce the resistance of the auxiliary wiring, the auxiliary portion is relayed through the contact portion 115B formed of a laminated film made of Ti as the uppermost layer. The wiring 118 </ b> B and the light extraction side electrode (second electrode 120) can be preferably electrically connected.

  By the way, as in Comparative Example 2, the contact portion 115B that relays the electrical connection between the auxiliary wiring 118B and the light extraction side electrode (second electrode 120) is a laminated film using Ti and Al as described above. In this case, reactive ion etching using chlorine gas or boron trichloride gas is generally used for etching Ti and Al stacks. Although this etching method has the advantage of excellent processing accuracy that the difference between the line width of the photoresist pattern and the pattern line width after etching is small, pattern defects due to foreign matter generated during Al etching are likely to occur. In particular, when the Al film thickness is increased in order to reduce the wiring resistance of the source signal line and the current supply line by increasing the screen size and definition of the panel, it causes a decrease in yield.

  Further, it is effective for simplifying the process to form the contact portion 115B in the same layer as the source / drain wiring of the thin film transistor Tr. However, in the top emission type organic EL display, the source / drain layer and the pixel are formed. In general, a planarizing layer such as polyimide or acrylic resin is formed between the pixel electrode layers forming the electrodes with a film thickness of about 2 μm by spin coating similar to a photoresist. In this case, the electrode on the light extraction side is connected to the contact portion 115B through a contact hole formed in the planarization layer, but the contact resistance increases due to overcoming the step in the planarization layer. was there.

  In order to evaluate this contact resistance, the end portion of the contact portion 115B is not exposed at the portion in contact with the second electrode in the second comparative example, and the contact portions 15B and 25B in the first and second embodiments. The end of the Ti layer was set to be exposed. In either case, the contact width with the second electrode was 20 μm and the length was 100 μm. The resistance value R was calculated from the value of the voltage V when the current value I was 100 μA, and the contact resistance between the first electrode and the second electrode was measured. FIG. 13 shows the result.

  From the result of FIG. 13, the contact resistance slightly increases in the structure of FIG. 5 (first embodiment), but the contact resistance equivalent to that of Comparative Example 2 is obtained in the structure of FIG. 11 (second embodiment). It has been shown that the contact resistance does not substantially increase even when the technique for solving the yield in the wiring forming process as described above is used. In the structure of FIG. 5 (first embodiment), a connection resistance between the contact portion 15B and the auxiliary wiring 18B is generated, but the increase is slight because of the ohmic contact resistance.

[Third Embodiment]
FIG. 14 shows a planar configuration of the display area 110 of the organic EL display device 1 according to the third embodiment of the present invention, and FIG. 15 shows a sectional configuration along the line XV-XV in FIG. It is a representation. The organic EL display device 1 is described in the first embodiment except that the auxiliary wiring 15C has the same laminated structure as the contact portion 15B and is formed integrally with the contact portion 15B. The organic EL display device has the same configuration. Accordingly, the corresponding components will be described with the same reference numerals.

  The transparent substrates 10A and 10B, the thin film transistor Tr, the wiring layer 15A, the contact portion 15B, the protective insulating film 16, the planarizing insulating film 17A, the interelectrode insulating film 21, the sealing resin 17B, and the organic EL element EL are the same as those in the first embodiment. It is comprised similarly to a form.

  The auxiliary wiring 15C is formed in the same layer as the wiring layer 15A in the region between the first electrodes 18A. Similar to the auxiliary wiring 18B of the first embodiment, the auxiliary wiring 15C is for suppressing in-plane non-uniformity of the electrode voltage in the transparent second electrode 20 having high resistance. Therefore, the auxiliary wiring 15 </ b> C is configured to have a lower resistance than the second electrode 20 (for example, a material having a low resistivity). Specifically, as shown in FIG. 16, the auxiliary wiring 15C has the same laminated structure as the contact portion 15B and is formed integrally with the contact portion 15B. Thereby, in this organic EL display device 1, the connection resistance between the auxiliary wiring 15C and the contact portion 15B can be further reduced.

  Further, the planarizing insulating film 17A and the interelectrode insulating film 21 are provided with a forward tapered opening in a part of the formation region of the auxiliary wiring 15C (see FIG. 15). A conductive contact portion 15B is formed in the same layer as the wiring layer 15A between the bottom of the opening and the gate insulating film 12, and the second electrode 20 and the auxiliary wiring 18B are electrically connected to the contact portion 15B. Connected.

  The organic EL display device 1 can be manufactured as follows, for example.

  First, as shown in FIG. 17, a plurality of thin film transistors Tr are formed on the transparent substrate 10A in the same manner as in the first embodiment.

  Here, when the wiring layer 15A is formed, the contact portion 15B is simultaneously formed using the same material as the wiring layer 15A. The contact portion 15B is formed on the gate insulating film 12, that is, on the same layer as the wiring layer 15A, and between the first electrodes 18A as shown in FIG. At this time, the auxiliary wiring 15C is formed integrally with the contact portion 15B.

  That is, first, as shown in FIG. 18A, on the gate insulating film 12, for example, a Ti layer 15B1 (film thickness 50 nm), an Al layer 15B2 (film thickness 500 nm), and a Mo layer 15B3 (film thickness 50 nm) are formed. They are formed in order by sputtering. Next, as shown in FIG. 18B, using the photoresist film PH as a mask, the Mo layer 15B3 and the Al layer 15B2 are selectively removed by wet etching using, for example, phosphoric acid nitric acid. Subsequently, as shown in FIG. 18C, the Ti layer 15B1 is selectively removed by dry etching using, for example, chlorine gas, and a part of the surface of the Ti layer 15B1 is exposed as shown in FIG. Thus, the widened portion W is formed. After that, the photoresist film PH is peeled off. As a result, the contact portion 15B can be formed in the same layer as the wiring layer 15A, and the auxiliary wiring 15C can be formed integrally with the contact portion 15B.

  After the thin film transistor Tr, the contact portion 15B, and the auxiliary wiring 15C are formed, as shown in FIG. 19A, the thin film transistor Tr, the contact portion 15B, and the auxiliary wiring 15C are formed in the same manner as in the first embodiment. Then, a protective insulating film 16 and a planarizing insulating film 17A are formed, and an opening having a side surface with a forward taper shape as indicated by reference numeral P1 in the drawing is formed.

  After the opening is formed in the planarization insulating film 17A, as shown in FIG. 19B, the metal layer 18 is formed on the planarization insulating film 17A and the contact portion 15B in the same manner as in the first embodiment. Form. Subsequently, as shown in FIG. 19C, the metal layer 18 is selectively etched by, for example, photolithography to form the first electrode 18A at a position corresponding to each thin film transistor Tr.

  After forming the first electrode 18A, as shown in FIG. 20A, the interelectrode insulating film 21 is formed on the planarizing insulating film 17A and the first electrode 18A in the same manner as in the first embodiment. Form.

  After the interelectrode insulating film 21 is formed, as shown in FIG. 20B, the organic light emitting layer 19 is formed on each first electrode 18A by, for example, a vacuum evaporation method. Then, on the organic light emitting layer 19, the interelectrode insulating film 21, the planarizing insulating film 17A, and the contact portion 15B, the second electrode 20 made of the above-described material is uniformly formed with a thickness of, for example, about 10 nm by, for example, a vacuum deposition method. To form.

  Finally, after uniformly forming a protective film (not shown) made of the above-described material on the second electrode 20 by, for example, a CVD method, a sealing resin 17B is formed on the protective film (not shown). For example, it is uniformly formed by a dropping injection method, and this is sandwiched between the transparent substrates 10B made of the materials described above. Thus, the organic EL display device 1 of the present embodiment shown in FIGS. 14 and 15 is manufactured.

  Note that the organic EL display device 1 was actually manufactured by this manufacturing method, and the contact resistance between the first electrode and the second electrode was evaluated in the same manner as in the second embodiment. As shown, in the structure of FIG. 16 (third embodiment), a result equivalent to that of the structure of FIG. 11 (second embodiment) was obtained. That is, if the auxiliary wiring 15C has the same laminated structure as the contact portion 15B and is formed integrally with the contact portion 15B, the connection resistance between the auxiliary wiring 15C and the contact portion 15B can be further reduced. It has been found that the contact resistance can be substantially prevented from increasing.

  In the organic EL display device 1, as in the first embodiment, when a voltage is applied to the first electrode 18 </ b> A via the wiring layer 15 </ b> A and the thin film transistor Tr, the organic EL display device 1 corresponds to the potential difference with the second electrode 20. The organic light emitting layer 19 emits light with high brightness. The light from the organic light emitting layer 19 passes through the second electrode while being reflected by the first electrode 18A, and is emitted upward in FIG. 4, that is, toward the transparent substrate 10B. A predetermined image is displayed on the organic EL display device by emitting light corresponding to the pixel signal from the organic EL element EL arranged in each pixel.

  Here, in this organic EL display device 1, since the auxiliary wiring 15C has the same laminated structure as the contact portion 15B and is formed integrally with the contact portion 15B, the connection between the auxiliary wiring 15C and the contact portion 15B is performed. The resistance is even smaller. Therefore, the connection resistance between the second electrode 20 and the auxiliary wiring 15C is further reduced.

  Thus, in the present embodiment, in addition to the effects of the first embodiment, the auxiliary wiring 15C has the same laminated structure as the contact portion 15B and is formed integrally with the contact portion 15B. The connection resistance between the auxiliary wiring 15C and the contact portion 15B can be further reduced. Therefore, the connection resistance between the auxiliary wiring 15C and the contact portion 15B can be further reduced, and the display quality can be improved while ensuring low power consumption.

(Modules and application examples)
Hereinafter, application examples of the display device described in the above embodiment will be described. The display device according to the above embodiment is an image signal that is input from the outside or is generated internally, such as a television device, a digital camera, a notebook personal computer, a mobile terminal device such as a mobile phone, or a video camera. Alternatively, the present invention can be applied to display devices for electronic devices in various fields that display images.

(module)
The display device of the above-described embodiment is incorporated into various electronic devices such as application examples 1 to 5 described later, for example, as a module as illustrated in FIG. In this module, for example, a region 210 exposed from the sealing substrate 50 and the adhesive layer 40 is provided on one side of the substrate 11, and wirings of the signal line driving circuit 120 and the scanning line driving circuit 130 are provided in the exposed region 210. An external connection terminal (not shown) is formed by extending. The external connection terminal may be provided with a flexible printed circuit (FPC) 220 for signal input / output.

(Application example 1)
FIG. 23 illustrates an appearance of a television device to which the display device of the above embodiment is applied. The television apparatus has, for example, a video display screen unit 300 including a front panel 310 and a filter glass 320, and the video display screen unit 300 is configured by the display device according to each of the above embodiments. .

(Application example 2)
FIG. 24 shows the appearance of a digital camera to which the display device of the above embodiment is applied. The digital camera includes, for example, a flash light emitting unit 410, a display unit 420, a menu switch 430, and a shutter button 440. The display unit 420 is configured by the display device according to each of the above embodiments. Yes.

(Application example 3)
FIG. 25 illustrates the appearance of a notebook personal computer to which the display device of the above embodiment is applied. The notebook personal computer has, for example, a main body 510, a keyboard 520 for inputting characters and the like, and a display unit 530 for displaying an image. The display unit 530 is a display according to each of the above embodiments. It is comprised by the apparatus.

(Application example 4)
FIG. 26 shows the appearance of a video camera to which the display device of the above embodiment is applied. This video camera has, for example, a main body 610, a subject photographing lens 620 provided on the front side surface of the main body 610, a start / stop switch 630 at the time of photographing, and a display 640. Reference numeral 640 denotes the display device according to each of the above embodiments.

(Application example 5)
FIG. 27 illustrates an appearance of a mobile phone to which the display device of the above embodiment is applied. For example, the mobile phone is obtained by connecting an upper housing 710 and a lower housing 720 with a connecting portion (hinge portion) 730, and includes a display 740, a sub-display 750, a picture light 760, and a camera 770. Yes. The display 740 or the sub-display 750 is configured by the display device according to each of the above embodiments.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited to these embodiments, and various modifications can be made.

  For example, the formation positions of the contact portions 15B and 25B are not limited to the positions shown in FIG. 4 described in the above embodiment, that is, the same layer as the wiring layer 15A, or the same layer as the first electrode 18A and the auxiliary wiring 18B. However, it may be formed in another layer.

  Further, in the first embodiment, when the auxiliary wiring 18B is formed in the same layer as the first electrode 18A, in the third embodiment, the auxiliary wiring 15C is formed in the same layer as the wiring layer 15A and the contact portion 15B. However, the auxiliary wirings 18B and 15C may be formed in either layer. In addition, when the auxiliary wirings 18B and 15C are used together and connected by using a contact hole as appropriate, when one of the auxiliary wirings is disconnected, the other auxiliary wiring can be used.

  Further, in each of the above embodiments, the case where the width of the opening corresponding to the contact portion 15B of the interelectrode insulating film 21 is made wider than the opening of the lower planarizing insulating film 17A has been described. The opening of the insulating film 21 may be narrower than the opening of the planarizing insulating film 17A as long as the opening is a forward taper shape having a wide top and a narrow bottom.

  In addition, regarding the positional relationship between the planarizing insulating film 17A and the protective insulating film 16, the planarizing insulating film 17A may be disposed inside the protective insulating film 16 of the contact portion 15B when they are formed separately. Although desirable, it is not limited to this.

  Furthermore, in the second embodiment, all of the film formed in the manufacturing process of the thin film transistor Tr is left as a layer under the contact portion 15B. Alternatively, a film different from the thin film transistor Tr may be formed.

  In addition, the display device of the present invention is not limited to the organic EL display device including the organic EL element as described in the above embodiment, and can be applied to other display devices.

  Furthermore, the material and thickness of each component described in the above embodiment, or the film formation method and film formation conditions are not limited, and other materials and thicknesses may be used. Alternatively, film forming conditions may be used.

  In addition, in the above-described embodiment, the configuration of the organic EL display device 1 is specifically described. However, it is not necessary to provide all layers, and for example, a color filter layer is provided on the transparent substrate 10B side. And you may make it provide another layer.

It is a figure showing the structure of the display apparatus which concerns on the 1st Embodiment of this invention. FIG. 2 is an equivalent circuit diagram illustrating an example of the pixel drive circuit illustrated in FIG. 1. It is a top view showing the structure of the display area shown in FIG. It is sectional drawing in the IV-IV line of FIG. It is sectional drawing showing the structure of the contact part of the display apparatus shown in FIG. It is sectional drawing showing a part of main process of the manufacturing method of the display apparatus shown in FIG. FIG. 7 is a cross-sectional view illustrating a process following FIG. 6. FIG. 8 is a cross-sectional diagram illustrating a process following the process in FIG. 7. FIG. 9 is a cross-sectional diagram illustrating a process following the process in FIG. 8. 6 is a cross-sectional view illustrating a configuration of a contact portion in Comparative Example 1. FIG. It is sectional drawing showing the structure of the contact part of the display apparatus which concerns on 2nd Embodiment. 10 is a cross-sectional view illustrating a configuration of a contact portion as Comparative Example 2. FIG. It is a figure showing the evaluation result of contact resistance. It is a top view showing the structure of the display area of the display apparatus which concerns on 3rd Embodiment. It is sectional drawing in the XV-XV line | wire of FIG. FIG. 16 is a cross-sectional view illustrating a structure of a contact portion of the display device illustrated in FIG. 15. FIG. 16 is a cross-sectional view illustrating a part of a main process in the method for manufacturing the display device illustrated in FIG. 15. FIG. 18 is a cross-sectional diagram illustrating a process following the process in FIG. 17. FIG. 19 is a cross-sectional diagram illustrating a process following the process in FIG. 18. FIG. 20 is a cross-sectional diagram illustrating a process following the process in FIG. 19. It is a figure showing the evaluation result of contact resistance. It is a top view showing schematic structure of the module containing the display apparatus of the said embodiment. It is a perspective view showing the external appearance of the application example 1 of the display apparatus of the said embodiment. (A) is a perspective view showing the external appearance seen from the front side of the application example 2, (B) is a perspective view showing the external appearance seen from the back side. 12 is a perspective view illustrating an appearance of application example 3. FIG. 14 is a perspective view illustrating an appearance of application example 4. FIG. (A) is a front view of the application example 5 in an open state, (B) is a side view thereof, (C) is a front view in a closed state, (D) is a left side view, and (E) is a right side view, (F) is a top view and (G) is a bottom view.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Organic EL display device, 10A, 10B ... Transparent substrate, 11 ... Gate electrode, 12 ... Gate insulating film, 13A ... Silicon film, 13B ... n + amorphous silicon film, 14 ... Stopper insulating film, 15A ... Wiring layer, 15B ... Contact part, 15B1 ... Ti layer, 15B2 ... Al layer, 15B3 ... 15B3, 16 ... Protective insulating film, 17A ... Flattening insulating film, 17B ... Sealing resin, 18, 22 ... Metal layer, 18A ... First electrode , 18B ... auxiliary wiring, 19 ... organic light emitting layer, 20 ... second electrode, 21 ... interelectrode insulating film, 23 ... protective film, Tr ... thin film transistor.

Claims (3)

A plurality of driving elements and a wiring layer electrically connected to the driving elements;
It is composed of the same layer as the wiring layer and has a laminated structure of a plurality of conductive layers, and the lowermost titanium (Ti) layer of the plurality of conductive layers is wider than the width of other conductive layers. A contact portion having a wide widened portion,
A planarization insulating film that covers the drive element and the wiring layer and has an opening having a side surface of a forward tapered shape in which the top is wide and the bottom is narrow in a region corresponding to the contact portion;
It is made of aluminum or an alloy containing aluminum as a main component, has a lattice-like planar shape on the planarization insulating film, and has a portion that projects into the opening of the planarization insulating film, and the projecting portion is An auxiliary wiring in contact with the uppermost conductive layer of the contact portion;
A plurality of first electrodes made of aluminum or an alloy containing aluminum as a main component and formed corresponding to each drive element in the lattice of the auxiliary wiring on the planarization insulating film;
The opening is provided in a region between the plurality of first electrodes on the planarizing insulating film and has an opening communicating with the opening of the planarizing insulating film, and the opening is wider than the opening of the planarizing insulating film An inter-electrode insulating film having a side surface with a forward tapered shape having a width and a wide top and a narrow bottom;
A plurality of light emitting portions respectively formed on the first electrode;
It is made of a material that can transmit light from the light emitting portion, and is provided on the plurality of light emitting portions, on the interelectrode insulating film, in the opening of the interelectrode insulating film, and in the opening of the planarizing insulating film. the direct contact with the widened portion of the lowermost conductive layer of the contact portion in the opening of the planarization insulating film, e Bei a common second electrode,
A display device in which a film including an insulating film and a metal film formed on the drive element side is formed below the contact portion . The display device according to claim 1, wherein the contact portion includes the lowermost titanium (Ti) layer, the intermediate aluminum (Al) layer, and the uppermost molybdenum (Mo) layer. Forming a plurality of driving elements and a wiring layer on the substrate and electrically connecting the plurality of driving elements and the wiring layer;
A contact portion having a stacked structure of a plurality of conductive layers is formed by the same layer as the wiring layer, and another conductive layer is formed on the lowermost titanium (Ti) layer of the plurality of conductive layers. Providing a wider portion wider than the width;
Forming a planarization insulating film that covers the drive element and the wiring layer, and providing an opening having a side surface with a forward taper shape in which the top is wide and the bottom is narrow in a region corresponding to the contact portion of the planarization insulating film; ,
On the planarization insulating film, an auxiliary wiring made of aluminum or an alloy containing aluminum as a main component is formed in a grid-like planar shape, and a projecting part is provided in the opening of the planarizing insulating film, and the projecting part Is contacted with the uppermost conductive layer of the contact portion, and at the same time, aluminum or aluminum as a main component corresponding to each of the plurality of driving elements in the lattice of the auxiliary wiring on the planarization insulating film. Forming a plurality of first electrodes made of an alloy to be
An interelectrode insulating film is formed in a region between the plurality of first electrodes on the planarizing insulating film, an opening communicating with the opening of the planarizing insulating film is provided in the interelectrode insulating film, Providing a forward tapered side surface having a width wider than the opening of the planarization insulating film and having a wide top and a narrow bottom;
Forming a light emitting portion on each of the first electrodes;
The second electrode is shared by a material capable of transmitting light from each light emitting part on the plurality of light emitting parts, on the interelectrode insulating film, in the opening of the interelectrode insulating film, and in the opening of the planarizing insulating film. thereby forming on the second electrode, it viewed including the step of directly contacting the widened portion of the lowermost conductive layer of the contact portion in the opening of the planarization insulating film,
In the step of forming the contact portion, the lowermost titanium (Ti) layer, the intermediate aluminum (Al) layer, and the uppermost molybdenum (Mo) layer are formed, and a mask is formed on the uppermost layer. Is formed by selectively removing up to the intermediate layer by wet etching using the mask, and selectively removing the lowermost layer by dry etching using the mask. Forming the second electrode so as to cover the lowermost layer, the intermediate layer and the uppermost layer;
Manufacturing method of the table shows the device.

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