Display device and method of manufacturing the same

Abstract

A display device and a method for manufacturing the display device are provided. The display device includes: a substrate; a light emitting diode including a common electrode on the substrate; a first conductive layer on and in contact with the common electrode; a first insulating layer on the first conductive layer and having a first contact opening on the first conductive layer; and a common voltage line on the first insulating layer and electrically connected to the first conductive layer through the first contact opening.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0133651 filed on October 6, 2023, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] Aspects of embodiments of the present disclosure relate to a display device and a method of manufacturing the display device. Background Art

[0004] Display devices such as a liquid crystal display (LCD) and an organic light emitting diode display (OLED display) include a display panel including a plurality of pixels for displaying an image.

[0005] Each pixel includes a pixel electrode receiving a data signal, a plurality of transistors and one or more capacitors transmitting the data signal to the pixel electrode, and a common electrode opposite to the pixel electrode.

[0006] At least one layer may be positioned between the pixel electrode and the common electrode.

[0007] A common electrode can be formed across a plurality of pixels to deliver a constant (or common) voltage to each pixel. Summary of the invention

[0008] If there is a voltage drop in the common voltage transmitted by the common electrode, unevenness may occur in the brightness of the image displayed by the display panel. For example, as display devices become larger, defects due to uneven brightness caused by a voltage drop at the common electrode may become more noticeable.

[0009] The embodiments of the present disclosure increase contact stability between a common electrode and an auxiliary electrode and increase process stability in forming a structure of an auxiliary electrode electrically connected to the common electrode to reduce a voltage drop of a voltage transmitted by the common electrode.

[0010] In addition, embodiments of the present disclosure provide a display device that exhibits a reduced voltage drop at a common electrode without requiring an additional process and structure for contact between an auxiliary electrode and the common electrode.

[0011] The display device according to the embodiment includes a substrate, a light emitting diode including a common electrode on the substrate, a first conductive layer on and in contact with the common electrode, a first insulating layer on the first conductive layer and having a first contact opening on the first conductive layer, and a common voltage line on the first insulating layer. The common voltage line is electrically connected to the first conductive layer through the first contact opening.

[0012] The first contact opening may not overlap with the light emitting diode in a plane.

[0013] The first conductive layer may include a conductive metal oxide.

[0014] The first conductive layer may include indium gallium zinc oxide (IGZO).

[0015] The common voltage line may include a lower layer, an intermediate layer, and an upper layer sequentially stacked on each other. The lower layer and the upper layer may include at least one of a first metal and a nitride of the first metal, and the intermediate layer may include a second metal different from the first metal.

[0016] The first metal may include titanium (Ti).

[0017] The second metal may include aluminum (Al).

[0018] The first insulating layer may include an inorganic insulating material.

[0019] The display device may further include a second conductive layer over the first insulating layer, and the second conductive layer may have a second contact opening corresponding to the first contact opening. The common voltage line may be electrically connected to the first conductive layer through the first contact opening and the second contact opening.

[0020] The second conductive layer may include a conductive metal oxide.

[0021] The second conductive layer may include IGZO.

[0022] The second conductive layer may contact an upper surface of the first insulating layer.

[0023] The common voltage line may have a bottom surface contacting the first conductive layer, a side surface contacting the side surface of the first insulating layer and the side surface of the second conductive layer in the first contact opening and the second contact opening, and a lower surface contacting the upper surface of the second conductive layer outside the first contact opening and the second contact opening.

[0024] The display device may further include: a second insulating layer on the common voltage line; and a third insulating layer on the second insulating layer. The second insulating layer may include an organic insulating material, the third insulating layer may include an inorganic insulating material, and the first insulating layer, the second insulating layer and the third insulating layer may cover the light emitting diode together.

[0025] A display device according to another embodiment includes: a substrate; a light emitting diode including a common electrode on the substrate; a first conductive layer on the common electrode; a first insulating layer on the first conductive layer; a second conductive layer on the first insulating layer; and a common voltage line on the second conductive layer. The first insulating layer and the second conductive layer each have a contact opening above the first conductive layer, and the common voltage line is electrically connected to the first conductive layer through the contact opening.

[0026] The first conductive layer and the second conductive layer may include a conductive metal oxide.

[0027] The first conductive layer and the second conductive layer may include IGZO.

[0028] The display device may further include: a second insulating layer on the common voltage line; and a third insulating layer on the second insulating layer. The first insulating layer and the third insulating layer may include an inorganic insulating material, the second insulating layer may include an organic insulating material, and the first insulating layer, the second insulating layer, and the third insulating layer may cover the light emitting diode together.

[0029] The method for manufacturing a display device according to an embodiment includes: forming a light emitting diode including a common electrode on a substrate; forming a first conductive layer including a conductive metal oxide on the common electrode; forming a first insulating layer including an inorganic insulating material on the first conductive layer; forming a second conductive layer including a conductive metal oxide on the first insulating layer; etching the second conductive layer to form a first contact opening above the first conductive layer; etching the first insulating layer to form a second contact opening corresponding to the first contact opening; and forming a common voltage line on the second conductive layer. The common voltage line is electrically connected to the first conductive layer through the first contact opening and the second contact opening.

[0030] The first conductive layer and the second conductive layer may include IGZO, forming the first contact opening may include a wet etching process, forming the second contact opening may include a dry etching process, and forming the common voltage line may include a dry etching process.

[0031] According to the embodiment, in order to reduce a voltage drop of a voltage transmitted by the common electrode, contact stability of the common electrode and the auxiliary electrode and process stability can be improved by using a structure forming an auxiliary electrode electrically connected to the common electrode.

[0032] In addition, a voltage drop of the common electrode can be reduced without any additional process or structure for contact between the auxiliary electrode and the common electrode, and the same effect can be achieved in a high-resolution display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a plan view of an electrode layer and a common voltage line in one pixel of a display area of ​​a display device according to an embodiment.

[0034] Figure 2 is a cross-sectional view of one pixel of the display device according to the embodiment.

[0035] Figure 3 is a cross-sectional view of a portion of a display device according to an embodiment.

[0036] Figure 4 and Figure 5 are cross-sectional views of common voltage lines of a display device according to embodiments, respectively.

[0037] Figures 6 to 9 are cross-sectional views showing steps of a method of manufacturing a display device according to an embodiment. DETAILED DESCRIPTION

[0038] Hereinafter, with reference to the accompanying drawings, various embodiments of the present disclosure will be described in detail so that those skilled in the art can easily realize the present invention.

[0039] The present disclosure may be embodied in many different forms and is not limited to the embodiments described herein.

[0040] In order to more clearly explain aspects and features of the present disclosure, parts of the disclosed embodiments that are not related to the description may be omitted, and the same or similar components are given the same reference numerals throughout the specification.

[0041] In addition, the size and thickness of each component shown in the drawings may be arbitrarily shown for convenience of explanation, so the present disclosure is not necessarily limited to the shown contents.

[0042] In the drawings, the thickness may be exaggerated to clearly show various layers and regions.

[0043] Also, in the drawings, the thicknesses of some layers and regions may be exaggerated for convenience of explanation.

[0044] In addition, when a part of a layer, film, region or plate is referred to as being “on” or “on” another part, this includes not only the case where it is “directly” “on” the other part but also the case where there are other parts in between.

[0045] In contrast, when a part is referred to as being “right on top of” or “directly on top of” another part, it means that there are no other parts in between.

[0046] In addition, “above” or “on” a reference portion means positioned above or below the reference portion, and does not necessarily mean positioned “above” or “on” in a direction opposite to gravity.

[0047] In addition, throughout the specification, when a part is referred to as “comprising” a certain component, it means that it may also include other components, rather than excluding other components, unless specifically stated otherwise.

[0048] In addition, throughout the specification, when “on a plane” is mentioned, this means when the target portion is viewed from above, and when “in a cross section” is mentioned, this means when the cross section of the target portion is cut vertically and viewed from the side.

[0049] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. In addition, when describing the embodiments of the present disclosure, the use of "may" relates to "one or more embodiments of the present disclosure". Such as "at least one of..." and "any one of...", when after a column of elements, modify the entire column of elements, and do not modify the individual elements of the column. For example, the statement of "at least one of a, b and c" indicates only a, only b, only c, a and b, a and c, b and c, a, b and c, all, or its variants. As used herein, the terms "use", "using" and "used" can be considered as synonyms with the terms "utilize", "utilizing" and "utilized", respectively. As used herein, the terms "substantially", "about" and similar terms are used as approximate terms and are not used as terms of degree, and are intended to explain the inherent changes in measured values ​​or calculated values ​​that will be recognized by those of ordinary skill in the art.

[0050] It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or part from another element, component, region, layer, or part. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or part discussed below can be referred to as a second element, component, region, layer, or part.

[0051] The terms used in this article are for the purpose of describing embodiments of the present disclosure and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms "a" and "an" are also intended to include the plural forms.

[0052] Will refer to Figure 1 A display device according to the embodiment is described.

[0053] Figure 1 is a plan view of one electrode layer and a common voltage line in one pixel in a display area of ​​a display device according to an embodiment.

[0054] Reference Figure 1 , the display device according to the embodiment has a display area, and a plurality of pixels PX which are capable of displaying an image or configured as a unit for displaying an image are arranged in the display area.

[0055] The plurality of pixels PX may be arranged in a substantially (or substantially) matrix form on a plane in the display region, but the present disclosure is not limited thereto, and the plurality of pixels PX may be repeatedly arranged in various arrangement patterns.

[0056] Each pixel PX may include a plurality of sub-pixels PX1 , PX2 , and PX3 .

[0057] The plurality of sub-pixels PX1 , PX2 , and PX3 included in each pixel PX may display (or emit) light of different colors.

[0058] For example, the sub-pixels PX1 , PX2 , and PX3 are capable of individually displaying basic colors such as red, green, and blue.

[0059] The display device is configured to display images of various colors by combining various brightnesses of different basic colors displayed by the plurality of sub-pixels PX1 , PX2 , and PX3 .

[0060] The sub-pixels PX1 , PX2 , and PX3 may have light emitting regions LE1 , LE2 , and LE3 , respectively.

[0061] The subpixels PX1, PX2, and PX3 may include pixel electrodes 191a, 191b, and 191c, respectively, each for receiving a data signal including brightness information of display light (eg, light to be displayed or emitted), and a plurality of transistors electrically connected thereto.

[0062] The plurality of pixel electrodes 191 a , 191 b , and 191 c are positioned (or arranged) at the same layer on the substrate and may include the same material.

[0063] Each of the pixel electrodes 191a, 191b and 191c can be electrically connected to a transistor formed in a corresponding one of the sub-pixels PX1, PX2 and PX3 via an opening (e.g., a hole) 1184 formed in (or through) at least one insulating layer between the substrate and the corresponding one of the pixel electrodes 191a, 191b and 191c.

[0064] Each of the pixel electrodes 191 a , 191 b , and 191 c may overlap a corresponding one of the light emitting regions LE1 , LE2 , and LE3 on a plane.

[0065] The display device according to the embodiment may include a plurality of common voltage lines 170 transmitting a common voltage.

[0066] The common voltage line 170 may extend approximately in a first direction (eg, in a y direction in the drawing).

[0067] The common voltage line 170 may be positioned for each one or more pixels PX in a second direction (eg, an x ​​direction in the drawing) perpendicular to the first direction.

[0068] Figure 1 An embodiment in which one common voltage line 170 is positioned for each pixel PX (or extends through or adjacent to each pixel PX) in the second direction is illustrated, but the present disclosure is not limited thereto.

[0069] The common voltage line 170 may be positioned on a different conductive layer from the pixel electrodes 191 a , 191 b , and 191 c on the substrate.

[0070] According to an embodiment, a common voltage line 170 may be positioned in a conductive layer over the pixel electrodes 191 a , 191 b , and 191 c positioned on the substrate.

[0071] The common voltage line 170 may overlap the plurality of first contact openings 395 on a plane.

[0072] Will refer to Figures 2 to 5 Together with Figure 1 A detailed structure of a display device according to an embodiment will be described.

[0073] Figure 2 is a cross-sectional view of one pixel of a display device according to an embodiment, Figure 3 is a cross-sectional view of a portion of a display device according to an embodiment, and Figure 4 and Figure 5 are cross-sectional views of common voltage lines of a display device according to embodiments, respectively.

[0074] The display device according to the embodiment includes a substrate 110 , which may include (or may be formed of) glass, quartz, or plastic such as polyimide, and a buffer layer 111 , which is an insulating layer, may be positioned on the substrate 110 .

[0075] The first conductive layer including the light blocking pattern 177 may be located between the substrate 110 and the buffer layer 111 .

[0076] A semiconductor layer including a channel region 1132 and conductive regions 1131 and 1133 positioned on both sides of the channel region 1132 may be positioned on the buffer layer 111 .

[0077] The conductive region 1131 positioned on one side of the channel region 1132 may be a source region, and the conductive region 1133 positioned on the other side of the channel region 1132 may be a drain region, and vice versa.

[0078] The source region and the drain region may be referred to as a source electrode and a drain electrode, respectively.

[0079] The first insulating layer 120 may be positioned on the semiconductor layer.

[0080] A second conductive layer including a gate electrode 1155 and a lower electrode 1153 may be positioned on the first insulating layer 120 .

[0081] The gate electrode 1155 may overlap the channel region 1132 in a vertical direction (eg, in a z direction in the drawings).

[0082] The gate electrode 1155 may be electrically connected to the lower electrode 1153 , and in some embodiments, may be formed integrally with the lower electrode 1153 .

[0083] The channel region 1132 , the conductive regions 1131 and 1133 , and the gate electrode 1155 may together form one transistor.

[0084] The second insulating layer 160 may be located on the gate electrode 1155 and the lower electrode 1153 .

[0085] A third conductive layer including an upper electrode 1154 may be located on the second insulating layer 160 .

[0086] The upper electrode 1154 may form a capacitor by overlapping the lower electrode 1153 with the second insulating layer 160 therebetween.

[0087] The lower electrode 1153 may also overlap the light blocking pattern 177 with the first insulating layer 120 interposed therebetween.

[0088] The upper electrode 1154 may be electrically connected to the conductive region 1133 of the transistor through an opening 165 formed in the second insulating layer 160 and the first insulating layer 120 .

[0089] The third insulating layer 180 may be located on the upper electrode 1154 .

[0090] The third insulating layer 180 may include a first protective layer 180 a and a second protective layer 180 b .

[0091] The third insulating layer 180 may have a plurality of openings 1184 .

[0092] At least one of the first conductive layer, the second conductive layer and the third conductive layer may include (or may contain) copper (Cu), aluminum (Al), magnesium (Mg), silver (Ag), gold (Au), platinum (Pt), palladium (Pd), nickel (Ni), neodymium (Nd), iridium (Ir), molybdenum (Mo), tungsten (W), titanium (Ti), chromium (Cr), tantalum (Ta), etc., and may include alloys of the elements listed above or at least one metal oxide, such as indium tin oxide (ITO) and indium zinc oxide (IZO).

[0093] Each of the first conductive layer, the second conductive layer, and the third conductive layer may be made of a single layer or may include a plurality of layers.

[0094] For example, at least one of the first conductive layer, the second conductive layer, and the third conductive layer may have a multilayer structure including a lower layer containing (or comprising) titanium, an intermediate layer containing (or comprising) copper, and an upper layer containing (or comprising) ITO.

[0095] At least one of the buffer layer 111, the first insulating layer 120, the second insulating layer 160, and the third insulating layer 180 may include silicon nitride (SiN x ), silicon oxide (SiO x ), silicon oxynitride (SiO x N y ) or the like (or may be made thereof). At least one of the buffer layer 111, the first insulating layer 120, the second insulating layer 160, and the third insulating layer 180 may include an inorganic insulating material and / or an organic insulating material such as polyimide, an acrylic polymer, or a siloxane polymer.

[0096] The first protective layer 180 a of the third insulating layer 180 may include an inorganic insulating material (or may be made thereof), and the second protective layer 180 b may include an organic insulating material (or may be made thereof).

[0097] A fourth conductive layer including a plurality of pixel electrodes 191 may be positioned on the third insulating layer 180 .

[0098] The pixel electrode 191 may include a plurality of pixel electrodes 191a, 191b and 191c, for example, Figure 1 as shown in .

[0099] The fourth conductive layer may include a transparent metal oxide such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0100] The fourth conductive layer may be made of a single layer or may include a plurality of layers.

[0101] Reference Figure 3 The fourth conductive layer may have a multi-layer structure such as a three-layer structure in which, for example, a lower layer 19a including ITO, an intermediate layer 19b including silver (Ag), and an upper layer 19c including ITO are sequentially stacked.

[0102] The pixel electrode 191 may be electrically connected to the upper electrode 1154 through the opening 1184 .

[0103] The fourth insulating layer 350 may be located on the pixel electrode 191 .

[0104] The fourth insulating layer 350 may include an organic insulating material such as polyimide, polyamide, acrylic resin, benzocyclobutene (BCB), or phenolic resin, or a silicon dioxide-based inorganic insulating material.

[0105] The fourth insulating layer 350 may have a pixel opening 351 overlapping the pixel electrode 191 .

[0106] The light emitting layer 370 may be positioned on the fourth insulating layer 350 .

[0107] The light emitting layer 370 may include a low molecular weight organic material or a high molecular weight organic material such as PEDOT (poly(3,4-ethylenedioxythiophene)).

[0108] The light emitting layer 370 includes one or more of a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), and an electron injection layer (EIL), and may further include one or more other layers.

[0109] The light emitting layer 370 may be mainly positioned within the pixel opening 351 , and may include a portion positioned on the fourth insulating layer 350 .

[0110] At least a portion of the light emitting layer 370 may be formed by a deposition process.

[0111] At least a portion of the light emitting layer 370 may be positioned within the pixel opening 351 of the fourth insulating layer 350 and may contact the pixel electrode 191 .

[0112] The common electrode 270 is positioned on the light emitting layer 370 .

[0113] The common electrode 270 may be formed of a single (or unitary) conductor across a plurality of pixels.

[0114] The common electrode 270 may be completely located on the display area of ​​the substrate 110 (eg, may completely cover the display area of ​​the substrate 110 ).

[0115] The common electrode 270 may include a metal material containing (or including) silver (Ag) or a transparent metal oxide such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0116] The pixel electrode 191 , the light emitting layer 370 , and the common electrode 270 of each of the sub-pixels PX1 , PX2 , and PX3 together form a light emitting diode ED which is a light emitting device.

[0117] The pixel electrode 191 may be an anode and the common electrode 270 may be a cathode, but the reverse is also possible.

[0118] The lower conductive layer 381 may be located on the common electrode 270 .

[0119] The lower conductive layer 381 may be formed of a single conductor spanning across a plurality of pixels, and may be positioned entirely on the display area of ​​the substrate 110 (eg, may entirely cover the display area of ​​the substrate 110 ).

[0120] The lower conductive layer 381 may include a portion overlapping the light emitting diode ED and a portion overlapping the fourth insulating layer 350 .

[0121] The lower conductive layer 381 may contact an upper surface of the common electrode 270 and be electrically connected to the common electrode 270 to transfer a common voltage received from a common voltage line 170 to be described later to the common electrode 270 .

[0122] The lower conductive layer 381 may include a conductive metal oxide and a material capable of wet etching rather than dry etching.

[0123] For example, a material included in (or forming) the lower conductive layer 381 may have a high dry etching selectivity with respect to a fifth insulating layer 391 to be described later.

[0124] The lower conductive layer 381 may include, for example, IGZO having conductive properties.

[0125] When the lower conductive layer 381 includes IGZO, by using argon (Ar) instead of oxygen (O 2 )IGZO is deposited to form a lower conductive layer 381.

[0126] The lower conductive layer 381 may function as an etching preventing layer for the common electrode 270 and the fourth insulating layer 350 under the common electrode 270 during an etching process when forming a first contact opening 395 to be described later.

[0127] For example, the lower conductive layer 381 prevents the common electrode 270 and the fourth insulating layer 350 under the common electrode 270 from being damaged and consumed (eg, etched and removed) during an etching process for forming the first contact opening 395 .

[0128] The thickness of the lower conductive layer 381 (eg, thickness in the z direction) may be greater than the thickness of the common electrode 270 (eg, thickness in the z direction), but the present disclosure is not limited thereto.

[0129] The fifth insulating layer 391 may be positioned on the lower conductive layer 381 .

[0130] The fifth insulating layer 391 may form a portion of the encapsulation part, and may block the inflow of external moisture and oxygen by covering and sealing the light emitting diode ED which is the light emitting device.

[0131] The fifth insulating layer 391 may include an inorganic insulating material such as silicon oxide (SiOx ), silicon nitride (SiN x ) or silicon oxynitride (SiO x N y ).

[0132] The thickness of the fifth insulating layer 391 (eg, thickness in the z direction) may be in the range of approximately 100 angstroms to approximately 1000 angstroms, but is not limited thereto.

[0133] The fifth insulating layer 391 may have a first contact opening 395 exposing the lower conductive layer 381 in a region not overlapping with (eg, offset from) the light emitting diode ED.

[0134] The fifth insulating layer 391 may be completely removed at a region where the first contact opening 395 is to be formed.

[0135] The first contact opening 395 may be positioned to overlap the fourth insulating layer 350 .

[0136] The first contact opening 395 may be formed by a dry etching process.

[0137] The upper conductive layer 382 may be positioned on the fifth insulating layer 391 .

[0138] The upper conductive layer 382 may be formed of a single conductor spanning multiple pixels, and may be positioned entirely on the display area of ​​the substrate 110 (eg, may completely cover the display area of ​​the substrate 110 ).

[0139] The upper conductive layer 382 may include a portion overlapping the light emitting diode ED and a portion overlapping the fourth insulating layer 350 .

[0140] The upper conductive layer 382 may cover the fifth insulating layer 391 .

[0141] The fifth insulating layer 391 may be positioned between the lower conductive layer 381 and the upper conductive layer 382 .

[0142] The upper conductive layer 382 may include a conductive metal oxide, and may include a material capable of wet etching rather than dry etching.

[0143] The material included in the upper conductive layer 382 may have a high dry etching selectivity with respect to the common voltage line 170 .

[0144] The upper conductive layer 382 may include, for example, IGZO having conductive properties.

[0145] When the upper conductive layer 382 includes IGZO, by using argon (Ar) instead of oxygen (O 2 )IGZO is deposited to form an upper conductive layer 382.

[0146] The upper conductive layer 382 may have a second contact opening 385 corresponding to and overlapping the first contact opening 395 .

[0147] The second contact opening 385 and the first contact opening 395 may together form one contact opening 390 .

[0148] The second contact opening 385 may be formed by a wet etching process.

[0149] The upper conductive layer 382 may serve as an etching preventing layer for the fifth insulating layer 391 in an etching process for forming the common voltage line 170 to be described later.

[0150] For example, the upper conductive layer 382 may prevent the fifth insulating layer 391 from being damaged and consumed (eg, etched and removed) during a dry etching process of the common voltage line 170 .

[0151] The thickness of the upper conductive layer 382 (eg, thickness in the z direction) may be greater than the thickness of the common electrode 270 (eg, thickness in the z direction), but the present disclosure is not limited thereto.

[0152] The thickness of the lower conductive layer 381 and the upper conductive layer 382 (eg, thickness in the z direction) may be smaller than the thickness of the fifth insulating layer 391 (eg, thickness in the z direction), but the present disclosure is not limited thereto.

[0153] The common voltage line 170 may be positioned on the upper conductive layer 382 .

[0154] The common voltage line 170 may transmit a common voltage and may be referred to as an auxiliary electrode.

[0155] The common voltage line 170 may receive a common voltage from outside the display area.

[0156] The common voltage line 170 may be electrically connected by contacting the lower conductive layer 381 through the contact opening 390 , and may transfer the common voltage to the lower conductive layer 381 .

[0157] Therefore, the common electrode 270 contacting the lower conductive layer 381 can receive the common voltage from the common voltage line 170 .

[0158] Therefore, the common electrode 270 receives the common voltage from the common voltage line 170 at periodic positions within the display area, thereby reducing a voltage drop.

[0159] The common voltage line 170 has a bottom surface 170d in contact with the lower conductive layer 381, a side surface 170e in contact with the side surface of the fifth insulating layer 391 and the side surface of the upper conductive layer 382 in the contact opening 390, and may have a lower surface 170f in contact with the upper surface of the upper conductive layer 382 outside the contact opening 390 (for example, adjacent to the contact opening 390).

[0160] Since the common voltage line 170 is electrically connected to the upper conductive layer 382 , the upper conductive layer 382 can also transmit the common voltage.

[0161] According to the illustrated embodiment, a stable contact characteristic between the common electrode 270 and the common voltage line 170 can be ensured.

[0162] In addition, a voltage drop of the common electrode 270 can be reduced without any additional process or structure (such as laser drilling) penetrating the light emitting layer 370 for contact between the common electrode 270 and the common voltage line 170, thus making it easier to realize a high-resolution display device.

[0163] The common voltage line 170 may include a conductive metal.

[0164] For example, the common voltage line 170 may include a metal having good contact characteristics with the lower conductive layer 381 and the upper conductive layer 382 .

[0165] For example, refer to Figure 4 , the common voltage line 170 may include a plurality of layers including a lower layer 38 a , a middle layer 38 b , and an upper layer 38 c sequentially stacked from the bottom.

[0166] The lower layer 38 a , which may be in contact with the lower conductive layer 381 and the upper conductive layer 382 , may include at least one of a first metal and a nitride of the first metal.

[0167] For example, the first metal may include (or may be) titanium (Ti).

[0168] When the lower layer 38 a includes titanium nitride (TiN), contact characteristics between the common voltage line 170 and the lower and upper conductive layers 381 and 382 may be improved.

[0169] The middle layer 38b positioned between the lower layer 38a and the upper layer 38c may include a second metal different from the first metal.

[0170] The second metal may have a lower resistance than the first metal.

[0171] For example, the second metal may include (or may be) aluminum (Al).

[0172] The upper layer 38c may include at least one of a third metal and a nitride of the third metal.

[0173] The third metal may be the same as the first metal.

[0174] The third metal may include, for example, titanium (Ti).

[0175] The common voltage line 170 may be patterned by dry etching.

[0176] For example, the material included in the common voltage line 170 may be patterned by dry etching.

[0177] Reference Figure 5 ,and Figure 4 Unlike the embodiment shown in , the common voltage line 170 according to the embodiment may omit at least one of the lower layer 38 a and the upper layer 38 c.

[0178] Figure 5 Shown with Figure 4 The embodiment shown in FIG. 1 is compared with an embodiment in which the lower layer 38 a of the common voltage line 170 is omitted.

[0179] Refer again Figure 3 , a sixth insulating layer 392 may be located on the common voltage line 170 and the upper conductive layer 382 .

[0180] The sixth insulating layer 392 may form part of the encapsulation part together with the fifth insulating layer 391 , and may block the inflow of external moisture and oxygen by covering and sealing the light emitting diode ED.

[0181] The sixth insulating layer 392 may include an organic insulating material, and may have a thickness (eg, thickness in the z direction) greater than a thickness (eg, thickness in the z direction) of the fifth insulating layer 391 .

[0182] The seventh insulating layer 393 may be positioned on the sixth insulating layer 392 .

[0183] The seventh insulating layer 393 may form part of the encapsulation part together with the fifth insulating layer 391 and the sixth insulating layer 392 , and cover and seal the light emitting diode ED to prevent inflow of external moisture and oxygen.

[0184] The seventh insulating layer 393 may include an inorganic insulating material such as silicon oxide (SiO x ), silicon nitride (SiN x ) or silicon oxynitride (SiO x N y ).

[0185] The thickness of the fifth insulating layer 391 (eg, thickness in the z direction) may be in the range of approximately 100 angstroms to approximately 1000 angstroms, but is not limited thereto.

[0186] Will refer to Figures 6 to 9 The method of manufacturing the display device according to the embodiment is described together with the previously described drawings.

[0187] Figures 6 to 9 are cross-sectional views showing steps of a method of manufacturing a display device according to an embodiment.

[0188] First, refer to Figure 2 , Figure 3 and Figure 6 A first conductive layer, a buffer layer 111, a semiconductor layer, a first insulating layer 120, a second conductive layer, a second insulating layer 160, a third conductive layer, a third insulating layer 180, a fourth conductive layer, a fourth insulating layer 350, a light emitting layer 370 and a common electrode 270 are sequentially stacked and patterned on a substrate 110.

[0189] Next, refer to Figure 7 , a conductive metal oxide (such as IGZO) is deposited on the common electrode 270 to form a lower conductive layer 381.

[0190] When depositing IGZO, argon (Ar) can be used instead of oxygen (O 2 ).

[0191] Next, an inorganic insulating material (such as silicon oxide (SiO x ), silicon nitride (SiN x ) or silicon oxynitride (SiO x N y )) to form a fifth insulating layer 391.

[0192] Next, a conductive metal oxide (such as IGZO) is deposited on the fifth insulating layer 391 to form an upper conductive layer 382 .

[0193] When depositing IGZO, argon (Ar) can be used instead of oxygen (O 2 ).

[0194] Next, refer to Figure 8 , patterning the upper conductive layer 382 to form a plurality of second contact openings 385 .

[0195] At this time, an etching mask such as a photoresist can be formed, and a wet etching process can be used.

[0196] Next, the fifth insulating layer 391 is patterned by using an etching mask for forming the second contact openings 385 to form a plurality of first contact openings 395 corresponding to the second contact openings 385 .

[0197] At this time, a dry etching process may be used.

[0198] In this process, the lower conductive layer 381 having a higher dry etching selectivity than the fifth insulating layer 391 serves as an etching preventing layer to prevent the relatively thin common electrode 270 from being etched and damaged.

[0199] Next, refer to Fig. 9 , a conductive material including (or containing) metal is stacked on the upper conductive layer 382 and patterned to form the common voltage line 170 .

[0200] At this time, a dry etching process may be used.

[0201] In this process, the upper conductive layer 382 having a high dry etching selectivity compared to the common voltage line 170 serves as an etching preventing layer to prevent the fifth insulating layer 391 from being etched and damaged.

[0202] The common voltage line 170 is also formed in the first contact opening 395 and the second contact opening 385 such that it contacts the lower conductive layer 381 and conducts electricity thereto.

[0203] According to the embodiment, the manufacturing process is relatively simple without requiring an additional process such as laser drilling for contacting a common voltage line or an auxiliary electrode with a common electrode, resulting in high process stability and easy implementation.

[0204] Although the embodiments of the present disclosure have been described in detail above, the scope of the present disclosure is not limited thereto and various modifications and improvements may be made by those skilled in the art based on the basic concepts of the present disclosure as defined in the appended claims and their equivalents.

[0205] Description of some reference symbols

[0206] 110: Substrate

[0207] 111: Buffer layer

[0208] 120, 160, 180, 350, 391, 392, 393: Insulation layer

[0209] 165, 1184: Opening

[0210] 170: Common voltage line

[0211] 177: Light blocking pattern

[0212] 191, 191a, 191b, 191c: pixel electrodes

[0213] 270: Common electrode

[0214] 370: Luminous layer

[0215] 381: Lower conductive layer

[0216] 382: Upper conductive layer

[0217] 385, 390, 395: contact opening

[0218] 1131, 1133: Conductive area

[0219] 1132: Channel area

[0220] 1153: Lower electrode

[0221] 1154: Upper electrode

[0222] 1155: Gate electrode

Claims

1. A display device, comprising: substrate; a light emitting diode including a common electrode on the substrate; a first conductive layer on and contacting the common electrode; a first insulating layer overlying the first conductive layer and having a first contact opening overlying the first conductive layer; as well as A common voltage line is on the first insulating layer and electrically connected to the first conductive layer through the first contact opening.

2. The display device according to claim 1, wherein: The first contact opening does not overlap with the light emitting diode in a plane.

3. The display device according to claim 2, wherein: The first conductive layer includes a conductive metal oxide.

4. The display device according to claim 3, wherein: The first conductive layer includes indium gallium zinc oxide.

5. The display device according to claim 1 , further comprising a lower layer, a middle layer, and an upper layer stacked sequentially in the common voltage line, in, The lower layer and the upper layer include at least one of a first metal and a nitride of the first metal, and Wherein, the intermediate layer includes a second metal different from the first metal.

6. The display device according to claim 5, wherein: The first metal includes titanium.

7. The display device according to claim 6, wherein: The second metal includes aluminum.

8. The display device according to claim 1, wherein: The first insulating layer includes an inorganic insulating material.

9. The display device according to claim 1, further comprising a second conductive layer on the first insulating layer, in, The second conductive layer has a second contact opening corresponding to the first contact opening, and The common voltage line is electrically connected to the first conductive layer through the first contact opening and the second contact opening.

10. The display device according to claim 9, wherein: The second conductive layer includes a conductive metal oxide.

11. The display device according to claim 10, wherein: The second conductive layer includes indium gallium zinc oxide.

12. The display device according to claim 9, wherein: The second conductive layer contacts an upper surface of the first insulating layer.

13. The display device according to claim 9, wherein: The common voltage line has a bottom surface contacting the first conductive layer, a side surface contacting the side surface of the first insulating layer and the side surface of the second conductive layer in the first contact opening and the second contact opening, and a lower surface contacting the upper surface of the second conductive layer outside the first contact opening and the second contact opening.

14. The display device according to claim 1, further comprising: a second insulating layer on the common voltage line; as well as a third insulating layer on the second insulating layer, Wherein, the second insulating layer comprises an organic insulating material, Wherein, the third insulating layer comprises an inorganic insulating material, and The first insulating layer, the second insulating layer and the third insulating layer together cover the light emitting diode.

15. A display device, comprising: substrate; a light emitting diode including a common electrode on the substrate; a first conductive layer on the common electrode; a first insulating layer on the first conductive layer; a second conductive layer on the first insulating layer; as well as a common voltage line on the second conductive layer, The first insulating layer and the second conductive layer each have a contact opening above the first conductive layer, and The common voltage line is electrically connected to the first conductive layer through the contact opening.

16. The display device according to claim 15, wherein: The first conductive layer and the second conductive layer include a conductive metal oxide.

17. The display device according to claim 16, wherein: The first conductive layer and the second conductive layer include indium gallium zinc oxide.

18. The display device according to claim 15, further comprising: a second insulating layer on the common voltage line; as well as a third insulating layer on the second insulating layer, Wherein, the first insulating layer and the third insulating layer include inorganic insulating materials, Wherein, the second insulating layer comprises an organic insulating material, and The first insulating layer, the second insulating layer and the third insulating layer together cover the light emitting diode.

19. A method for manufacturing a display device, the method comprising: forming a light emitting diode including a common electrode on a substrate; forming a first conductive layer including a conductive metal oxide on the common electrode; forming a first insulating layer including an inorganic insulating material on the first conductive layer; forming a second conductive layer including a conductive metal oxide on the first insulating layer; etching the second conductive layer to form a first contact opening above the first conductive layer; etching the first insulating layer to form a second contact opening corresponding to the first contact opening; as well as forming a common voltage line on the second conductive layer, The common voltage line is electrically connected to the first conductive layer through the first contact opening and the second contact opening.

20. The method for manufacturing a display device according to claim 19, wherein: The first conductive layer and the second conductive layer include indium gallium zinc oxide, Wherein, forming the first contact opening comprises a wet etching process, Wherein, forming the second contact opening comprises a dry etching process, and Wherein, forming the common voltage line includes a dry etching process.

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