Display device including a light-emitting element between a first electrode and a second electrode thereon

A display device includes a substrate having an emission area and a non-emission area, a first electrode and a second electrode spaced from each other on the substrate in the emission area, a first insulating layer on the substrate in the emission area and the non-emission area and covering at least a portion of the first electrode and the second electrode, a light-emitting element between the first electrode and the second electrode, a first contact electrode on the first electrode and in contact with one end portion of the light-emitting element, and a second contact electrode on the second electrode and in contact with the other end portion of the light-emitting element, a first active material layer on the first insulating layer in the non-emission area and electrically connected to the first contact electrode, and a gate insulating layer on the first active material layer.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0145768, filed on Nov. 14, 2019 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

The present disclosure relates to a display device.

2. Description of the Related Art

The importance of display devices is increasing with the development of multimedia. Accordingly, various types of display devices such as an organic light-emitting display (OLED) device or a liquid crystal display (LCD) device are being used.

Display devices are devices that display an image and include a display panel such as an organic light-emitting display panel or a liquid crystal display panel. Among these, the display device may include light-emitting elements as a light-emitting display panel. For example, a light-emitting diode (LED) may include an organic LED that uses an organic material as a fluorescent material, an inorganic LED that uses an inorganic material as a fluorescent material, or the like.

SUMMARY

Aspects of the present disclosure provide a display device including a light-emitting element and a transistor in which an active material layer includes an oxide semiconductor.

Aspects of the present disclosure also provide a display device whose fabricating process is simplified by performing a process of forming the above-described transistor above the light-emitting element.

It should be noted that aspects of the present disclosure are not limited to the above-described aspects, and other aspects of the present disclosure will be apparent to those skilled in the art from the following descriptions.

According to some example embodiments of the present disclosure, a display device includes a substrate having an emission area and a non-emission area, a first electrode and a second electrode spaced from each other on the substrate in the emission area, a first insulating layer on the substrate in the emission area and the non-emission area and covering at least a portion of the first electrode and the second electrode, a light-emitting element between the first electrode and the second electrode, a first contact electrode on the first electrode and in contact with one end portion of the light-emitting element, and a second contact electrode on the second electrode and in contact with the other end portion of the light-emitting element, and a first active material layer on the first insulating layer in the non-emission area and electrically connected to the first contact electrode, a gate insulating layer on the first active material layer, a gate electrode on the gate insulating layer and overlapping the first active material layer, and an one electrode in contact with at least one side of the first active material layer, wherein the first contact electrode and the second contact electrode are at the same layer as the first active material layer.

In some example embodiments, the first active material layer, the first contact electrode, and the second contact electrode may include an oxide semiconductor.

In some example embodiments, the first active material layer may include a first conductive area, a second conductive area, and a channel area positioned between the first conductive area and the second conductive area, and the first contact electrode and the second contact electrode may include the same material as the first conductive area.

In some example embodiments, the light-emitting element may not overlap at least the first active material layer in a thickness direction.

In some example embodiments, the display device may further include a second insulating layer on the first contact electrode, the second contact electrode, and the first active material layer in the emission area and the non-emission area.

In some example embodiments, at least a portion of the first contact electrode and the second contact electrode may be on the first insulating layer.

In some example embodiments, the second insulating layer may cover at least a portion of the first active material layer and the gate electrode.

In some example embodiments, the one electrode may be on the second insulating layer and may be in contact with the first contact electrode.

In some example embodiments, the display device may further include a third insulating layer on the light-emitting element and exposing both end portions of the light-emitting element.

In some example embodiments, the first contact electrode and the second contact electrode may be in contact with the third insulating layer.

In some example embodiments, the display device may further include a color filter layer on the second insulating layer and overlapping the light-emitting element.

In some example embodiments, the display device may further include a reflective layer on the second insulating layer and overlapping the second electrode.

In some example embodiments, the display device may further include a light-shielding layer between the first insulating layer, and the substrate and below the first active material layer in the non-emission area.

In some example embodiments, the display device may further include a first bank between the first electrode and the substrate, and a second bank between the second electrode and the substrate.

In some example embodiments, the first electrode, the second electrode, and the light-shielding layer may include a first metal layer on the substrate and a second metal layer on the first metal layer.

In some example embodiments, the first metal layer may have a width greater than a width of the second metal layer, and the second metal layer has a thickness greater than a thickness of the first metal layer.

According to some example embodiments of the present disclosure, a display device includes a substrate having an emission area and a non-emission area, a first electrode on the substrate in the emission area and extending in a first direction, a second electrode spaced from the first electrode in a second direction and extending in the first direction, a plurality of light-emitting elements between the first electrode and the second electrode, a first contact electrode extending in the first direction on the first electrode and in contact with one end portion of each of the light-emitting elements, a second contact electrode extending in the first direction on the second electrode and in contact with the other end portion of each of the light-emitting elements, a first voltage line located in the non-emission area and extending in the first direction, a first semiconductor area located in the non-emission area and extending in the second direction and partially overlapping the first voltage line and an one electrode overlapping the first contact electrode and one side of the first semiconductor area.

In some example embodiments, the display device may further include a light-shielding layer located in the non-emission area and extending in the first direction to partially overlap the first semiconductor area.

In some example embodiments, the first semiconductor area may be in contact with the first voltage line through a first contact hole exposing the first voltage line in an area overlapping the first voltage line, and the one electrode may be in contact with the first contact electrode and one side of the first semiconductor area.

In some example embodiments, a pad electrode may be on the first voltage line exposed through the first contact hole, and the first semiconductor area may be in contact with the pad electrode.

DETAILED DESCRIPTION

Example embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which example embodiments of the present disclosure are shown. Example embodiments of the present disclosure may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will filly convey the scope of the present disclosure to those skilled in the art.

Hereinafter, example embodiments will be described with reference to the attached drawings.

FIG.1is a schematic plan view of a display device according to some example embodiments of the present disclosure.

Referring toFIG.1, a display device10displays a video or a still image. The display device10may refer to all electronic devices that provide display screens. For example, the display device10may include televisions, notebooks, monitors, advertising boards, devices for Internet of Things (IoT), mobile phones, smart phones, tablet personal computers (PCs), electronic watches, smart watches, watch phones, head-mounted displays, mobile communication terminals, electronic notebooks, electronic book readers, portable multimedia players (PMPs), navigation devices, game machines, digital cameras, camcorders, and the like, which provide display screens.

The display device10includes a display panel that provides a display screen. Examples of the display panel may include a light-emitting diode (LED) display panel, an organic light-emitting display panel, a quantum dot light-emitting display panel, a plasma display panel, a field emission display panel, and the like. Hereinafter, although an example in which the LED display panel as the example of the display panel is described, the present disclosure is not limited thereto, and when the same technical spirit is applicable, it may be applied to other display panels.

A shape of the display device10may be variously modified. For example, the display device10may have shapes such as a rectangular shape of which lateral sides are long, a rectangular shape of which longitudinal sides are long, a square shape, a quadrangular shape of which corner portions (vertexes) are round, other polygonal shapes, a circular shape, and the like. A shape of a display area DA of the display device10may also be similar to an overall shape of the display device10. InFIG.1, the display device10and the display area DA, which have the rectangular shape of which lateral sides are long, are illustrated.

The display device10may include the display area DA and a non-display area NDA. The display area DA is an area in which an image may be displayed, and the non-display area NDA is an area in which an image is not displayed. The display area DA may refer to an active area and the non-display area NDA may refer to an inactive area.

The display area DA may generally occupy a center portion of the display device10. The display area DA may include a plurality of pixels PX. The plurality of pixels PX may be arranged in a matrix form. A shape of each of the pixels PX may be a rectangular shape or a square shape in a plan view, but the present disclosure is not limited thereto, and may be a rhombus shape of which sides are inclined with respect to a first direction DR1. Each of the pixels PX may include one or more light-emitting elements, which emit light in a specific wavelength range, to display a specific color.

Although not illustrated in the drawing, the plurality of pixels PX may include a first pixel that emits light of a first color, a second pixel that emits light of a second color, and a third pixel that emits light of a third color. In some example embodiments, the first color, the second color, and the third color may be different from each other so that the first color may be blue, the second color may be green, and the third color may be red. However, the present disclosure is not limited thereto, and the plurality of pixels PX may emit light of the same color.

Each of the pixels may include a driving transistor, at least one switching transistor, a light-emitting element, and a capacitor. Because the switching transistor is turned on when a scan signal is applied through a scan line SCL, a data voltage of a data line DTL may be applied to a gate electrode of the driving transistor. The driving transistor supplies a driving current to the light-emitting element according to the data voltage applied to the gate electrode thereof so that the light-emitting element may emit light. The driving transistor and at least one switching transistor may be thin-film transistors (TFTs). The light-emitting element may emit light according to the driving current of the driving transistor. The light-emitting element may be an inorganic light-emitting diode including a semiconductor layer and an active layer. The capacitor may serve to constantly maintain the data voltage applied to the gate electrode of the driving transistor.

FIG.2is an equivalent circuit diagram illustrating one pixel ofFIG.1, according to some embodiments of the present disclosure.

Referring toFIG.2, the pixel PX may include a driving transistor DT, a switching transistor ST, a light-emitting element300, and a capacitor Cst.FIG.2illustrates that each pixel PX has a two transistor-one-capacitor (2T1C) structure having one driving transistor DT, one switching transistor ST, and one capacitor Cst, but the present disclosure is not limited thereto. Each pixel PX may include more transistors and a plurality of capacitors.

Each of the driving transistor DT and the switching transistor ST may include one electrode, the other electrode, and a gate electrode. One of the one electrode and the other electrode may be a source electrode, and the other one may be a drain electrode.

Each of the driving transistor DT and the switching transistor ST may be formed of a thin-film transistor (TFT). For example, inFIG.2, it is illustrated that each of the driving transistor DT and the switching transistor ST is formed of an N-type metal oxide semiconductor field-effect transistor (MOSFET), but the present disclosure is not limited thereto. Each of the driving transistor DT and the switching transistor ST may be formed of a P-type MOSFET. In some embodiments, positions of the source electrode and the drain electrode of each of the driving transistor DT and the switching transistor ST may be changed. Hereinafter, the case in which the driving transistor DT and the first switching transistor ST are formed of N-type MOSFETs will be described as an example.

The driving transistor DT supplies a driving current to the light-emitting element300according to a data voltage applied to the gate electrode thereof so that the light-emitting element300may emit light. For example, in the driving transistor DT, the gate electrode may be connected to the source electrode of the switching transistor ST, the source electrode may be connected to a first electrode of the light-emitting element300, and the drain electrode may be connected to a first power line VDL through which a first power voltage is applied.

The switching transistor ST is turned on when a scan signal is applied at the gate electrode of the switching transistor ST through the scan line SCL so that a dlq line DTL may be applied to the gate electrode of the driving transistor DT. For example, in the switching transistor ST, the gate electrode may be connected to the scan line SCL, the source electrode may be connected to the gate electrode of the driving transistor DT, and the drain electrode may be connected to the data line DTL.

The capacitor Cst may be connected between the gate electrode and the source electrode of the driving transistor DT. Accordingly, the capacitor Cst may serve to substantially uniformly maintain the data voltage applied to the gate electrode of the driving transistor DT.

The light-emitting element300may emit light according to the driving current of the driving transistor DT. The light-emitting element300may include a first electrode and a second electrode. The first electrode of the light-emitting element300may be connected to the source electrode of the driving transistor DT and the second electrode of the light-emitting element300may be connected to a second power line VSL through which a second power voltage lower than the first power voltage is applied.

Hereinafter, the structure of the display device10will be described in detail with reference to other drawings of the present disclosure.

FIG.3is a layout diagram illustrating one pixel of the display device according to some example embodiments of the present disclosure.

Referring toFIG.3, each pixel PX of the display device10may include an emission area EMA and a non-emission area NEA. The emission area EMA may be defined as an area in which the light-emitting element300included in the display device10is disposed to emit light in a specific wavelength range. The light-emitting element300includes an active layer330(e.g., as shown inFIG.5), and the active layer330may emit light in a specific wavelength range without directivity. For example, the light emitted from the active layer330of the light-emitting element300may also be emitted in directions toward side surfaces of the light-emitting element300including both ends thereof. The emission area EMA of each pixel PX may include an area in which the light-emitting element300is disposed and an area adjacent to the light-emitting element300to which the light is emitted from the light-emitting element300. Further, the present disclosure is not limited thereto, and the emission area EMA may also include an area to which the light emitted by the light-emitting element300is reflected or refracted by another component, element, or member. A plurality of light-emitting elements300may be disposed in each pixel PX, and the area in which the light-emitting elements are disposed and areas that are adjacent thereto may together form the emission area EMA.

The non-emission area NEA is an area other than the emission area EMA in each pixel PX. The non-emission area NEA may be defined as an area in which the light-emitting elements300are not disposed and the light emitted from the light-emitting elements300does not reach so that light is not emitted from the non-emission area NEA. Also, as illustrated in the drawing, a plurality of lines and circuit elements may be disposed in the non-emission area NEA. The driving transistor DT, the switching transistor ST, and the capacitors Cst of each pixel PX, and a plurality of lines may be disposed in the non-emission area NEA.

The display device10, according to some example embodiments, includes the emission area EMA in which the light-emitting elements300are disposed and the non-emission area NEA in which the light-emitting elements300are not disposed, and the light-emitting elements300that emit light displayed by each pixel PX and the circuit elements for driving the light-emitting elements300may be disposed in the areas distinguished from each other. For example, in the display device10according to some example embodiments, the light-emitting elements300that emit light and the circuit elements for driving the light-emitting elements300may be disposed in different areas, for example, disposed in the emission area EMA and the non-emission area NEA, respectively, and may not overlap each other in a thickness direction. The light-emitting element300may not overlap at least a first active material layer126(for example, seeFIG.4) of the driving transistor DT in the thickness direction, and accordingly, the display device10may emit light upward or downward on the basis of the area in which the light-emitting elements300are disposed.

In some embodiments, the display device10may include a substrate110(e.g., seeFIG.4), a semiconductor layer disposed on the substrate110, a plurality of conductive layers, and the plurality of light-emitting elements300. In some embodiments, a plurality of insulating layers may be disposed between the semiconductor layer and the conductive layer. The emission area EMA and the non-emission area NEA are defined on the substrate110, and the semiconductor layer, the conductive layer, and the light-emitting elements300may be respectively disposed in the corresponding one of the emission area EMA and the non-emission area NEA.

A first conductive layer may include a data line1210, a first voltage line1220, a second voltage line1230, a first electrode240, a second electrode250, a light-shielding layer260, and a first capacitor electrode1270. The data line1210, the first voltage line1220, the second voltage line1230, the light-shielding layer260, and the first capacitor electrode1270are disposed in the non-emission area NEA, and the first electrode240and the second electrode250are disposed in the emission area EMA. The first electrode240and the second electrode250may be electrically connected to the light-emitting element300.

The data line1210may transfer a data signal to each pixel PX. The data line1210may be disposed at one side in the first direction DR1, for example, at a left side in the non-emission area NEA on the basis of a center portion of one pixel PX, and may extend in a second direction DR2. The data line1210may extend to another pixel PX positioned adjacent to the one pixel PX in the second direction DR2.

The first voltage line1220may transfer a first power voltage VDD to each pixel PX. For example, the first voltage line1220may be the first power line VDL ofFIG.2. The first voltage line1220may be disposed at one side of the data line1210in the non-emission area NEA, for example, at a right side of the data line1210, and may extend in the second direction DR2. The first voltage line1220may extend to another pixel PX positioned adjacent to the one pixel PX in the second direction DR2. The first voltage line1220may be in contact with a first semiconductor area2100through a second contact hole CNT2, which will be described below, to transfer the first power voltage VDD to the driving transistor DT of each pixel PX.

The second voltage line1230may transfer a second power voltage VSS to each pixel PX. For example, the second voltage line1230may be the second power line VSL ofFIG.2. The second voltage line1230may be disposed at one side of the first voltage line1220in the non-emission area NEA, for example, at a right side of the first voltage line1220, and may extend in the second direction DR2. The second voltage line1230may extend to another pixel PX positioned adjacent to the one pixel PX in the second direction DR2. The second voltage line1230may be in contact with a conductive line4600through a fifth contact hole CNT5, which will be described below, to transfer the second power voltage VSS to the second electrode250(e.g., seeFIG.4) of each pixel PX.

The light-shielding layer260may be disposed at one side of the second voltage line1230, for example, at a right side of the second voltage line1230, and may extend in the second direction DR2. In some embodiments, the light-shielding layer260may be electrically connected to the source electrode of the driving transistor DT. The light-shielding layer260is disposed to overlap the first active material layer126(e.g., seeFIG.4) of the driving transistor DT, which will be described below, to prevent light from being incident on (or to reduce the amount of light incident on) the first active material layer126. As an example, the light-shielding layer260may be made of an opaque metallic material that blocks (or substantially blocks) light from being transmitted.

The first electrode240may transfer the first power voltage VDD to the light-emitting element300. The first electrode240may be electrically connected to one end portion of the light-emitting element300and the driving transistor DT and may transfer the first power voltage VDD transferred through the first voltage line1220to the light-emitting element300. The first electrode240may be disposed at one side in the emission area EMA, for example, a left side in the emission area EMA, which is adjacent to the non-emission area NEA, and may extend in the second direction DR2. Unlike the first voltage line1220, the first electrode240does not extend to another adjacent pixel PX in the second direction DR2and may be disposed in each pixel PX.

The second electrode250may transfer the second power voltage VSS to the light-emitting element300. The second electrode250may be electrically connected to the other end portion of the light-emitting element300and the conductive line4600and may transfer the second power voltage VSS transferred through the second voltage line1230to the light-emitting element300. The second electrode250may be disposed at the other side in the emission area EMA, for example, at a right side in the emission area EMA, which is spaced from the non-emission area NEA, and may extend in the second direction DR2. For example, the second electrode250and the first electrode240may be spaced from each other and may face each other. The light-emitting element300may be disposed in a space between the first electrode240and the second electrode250. Unlike the first voltage line1220, the second electrode250does not extend to another adjacent pixel PX in the second direction DR2and may be disposed in each pixel PX.

A plurality of electrodes240and250may be electrically connected to the light-emitting elements300and may receive a predetermined voltage (e.g., a set voltage) to allow the light-emitting elements300to emit light in a specific wavelength range. In some embodiments, at least a portion of each of the electrodes240and250may be utilized to form an electric field in the pixel PX, thereby aligning the light-emitting elements300.

The plurality of electrodes240and250may include the first electrode240and the second electrode250. In some example embodiments, the first electrode240may be a pixel electrode that is separated for each pixel PX, and the second electrode250may be a common electrode which is commonly connected along each pixel PX. One of the first electrode240and the second electrode250may be an anode of the light-emitting element300, and the other one thereof may be a cathode of the light-emitting element300. However, the present disclosure is not limited thereto and the reverse of the above description may be possible.

The first capacitor electrode1270may be connected to the first electrode240and disposed between the first electrode240and the light-shielding layer260in the non-emission area NEA. The first capacitor electrode1270may overlap a second capacitor electrode4400with the insulating layer therebetween. Thus, the first capacitor electrode1270and the second capacitor electrode4400may form the capacitor Cst ofFIG.2.

The first conductive layer may include one or more metals selected from among molybdenum (Mo), aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chrome (Cr), calcium (Ca), titanium (Ti), tantalum (Ta), tungsten (W), and copper (Cu). The first conductive layer may be formed as a single-layer film or a multilayer film. For example, the first conductive layer may be formed in a stacked structure of Ti/Al/Ti, Mo/Al/Mo, Mo/AlGe/Mo, Ti/Cu, and the like.

In some embodiments, each of the electrodes240and250may include a transparent conductive material. As an example, each of the electrodes240and250may include materials such as indium tin oxide (ITO), indium zinc oxide (IZO), indium tin-zinc oxide (ITZO), and the like, but the present disclosure is not limited thereto. In some example embodiments, each of the electrodes240and250may include a conductive material having high reflectance. For example, each of the electrodes240and250may include a metal such as Ag, Cu, Al, or the like as a material having high reflectance. In some embodiments, light incident on each of the electrodes240and250may be reflected and emitted in an upward direction with respect to each pixel PX.

Further, each of the electrodes240and250may be formed in a structure, in which one or more layers of a transparent conductive material and a metal layer having high reflectance are stacked, or formed as a single layer including the transparent conductive material and the metal layer. In some example embodiments, each of the electrodes240and250may have a stacked structure of ITO/Ag/ITO/IZO or may be an alloy including Al, Ni, lanthanum (La), and the like. However, the present disclosure is not limited thereto.

A first insulating layer510is disposed on the first conductive layer (e.g., seeFIG.4). The first insulating layer510may be disposed on the first conductive layer and the substrate110to cover the first conductive layer and the substrate110and may be disposed to partially expose the first electrode240and the second electrode250. A detailed description thereof will be made below.

The light-emitting element300may be disposed between the first electrode240and the second electrode250in the emission area EMA. One end portion of the light-emitting element300may be electrically connected to the first electrode240, and the other end portion thereof may be electrically connected to the second electrode250. The light-emitting element300may be electrically connected to the first electrode240and the second electrode250through contact electrodes361and362that will be described below.

The plurality of light-emitting elements300may be disposed to be spaced from each other and aligned to be substantially parallel to each other. A separation distance between the light-emitting elements300is not particularly limited. In some embodiments, the plurality of light-emitting elements300may be disposed adjacent to each other to form a group, and a plurality of other light-emitting elements300may be grouped in a state of being spaced at regular intervals and may have a nonuniform density but may be oriented in one direction to be arranged. In some embodiments, the light-emitting element300may have a shape extending in one direction, and a direction in which the light-emitting elements300extend may be substantially perpendicular to a direction in which each of the electrodes240and250extends. However, the light-emitting element300may be obliquely disposed without being perpendicular or substantially perpendicular to the direction in which each of the electrodes240and250extends.

The semiconductor layer and the contact electrodes361and362are disposed on the light-emitting element300and the first insulating layer510. The semiconductor layer includes the first semiconductor area2100, the second semiconductor area2200, and a third semiconductor area2300, which are disposed in the non-emission area NEA, and the contact electrodes361and362include a first contact electrode361disposed on the first electrode240and a second contact electrode362disposed on the second electrode250. The first semiconductor area2100, the second semiconductor area2200, and the third semiconductor area2300may form the active material layer of the switching transistor ST and the driving transistor DT of each pixel PX.

The first semiconductor area2100may have a shape that extends in the first direction DR1. As illustrated in the drawing, the first semiconductor area2100may extend in the first direction DR1from a lower side of the pixel PX with respect to the center portion of the pixel PX. The first semiconductor area2100may overlap at least the first voltage line1220and the light-shielding layer260. At least a portion of the first semiconductor area2100may be electrically connected to the first voltage line1220through a second contact hole CNT2exposing the first voltage line1220by passing through the first insulating layer510in an area overlapping the first voltage line1220.

The second semiconductor area2200may be spaced from the first semiconductor area2100and may have a shape extending in the first direction DR1. As illustrated in the drawing, the second semiconductor area2200may extend in the first direction DR1from an upper side of the pixel PX with respect to the center portion of the pixel PX. The second semiconductor area2200may overlap at least the data line1210. At least a portion of the second semiconductor area2200may be electrically connected to the data line1210through a first contact hole CNT1exposing the data line1210by passing through the first insulating layer510in an area overlapping the data line1210. In some embodiments, like the first semiconductor area2100, the second semiconductor area2200may partially overlap the light-shielding layer260.

The third semiconductor area2300may be connected to the second semiconductor area2200and may be branched from the semiconductor area2200, and extend in the second direction DR2toward the first semiconductor area2100. The third semiconductor area2300extends in the second direction DR2at a position adjacent to the center portion of the pixel PX and may be terminated such that the third semiconductor area2300is spaced from the first semiconductor area2100. The third semiconductor area2300may be electrically connected to a first gate electrode of the driving transistor DT, which will be described below.

The plurality of contact electrodes361and362may have shapes in which at least a portion thereof extend in one direction. The plurality of contact electrodes361and362may be in contact with the light-emitting elements300and the electrodes240and250, respectively, and the light-emitting elements300may receive electrical signals from the first electrode240and the second electrode250through the contact electrodes361and362.

The contact electrodes361and362may include the first contact electrode361and the second contact electrode362. The first contact electrode361and the second contact electrode362may be disposed on the first electrode240and the second electrode250, respectively.

The first contact electrode361may be disposed on the first electrode240, may extend in the second direction DR2, and may be in contact with one end portion of each of the light-emitting elements300. The second contact electrode362may be spaced from the first contact electrode361in the first direction DR1, may be disposed on the second electrode250, may extend in the second direction DR2, and may be in contact with the other end portion of each of the light-emitting elements300. The first contact electrode361and the second contact electrode362may be in contact with the first electrode240and the second electrode250, which are exposed because the first insulating layer510is not disposed thereon. The light-emitting elements300may be electrically connected to the first electrode240and the second electrode250through the first contact electrode361and the second contact electrode362.

In some embodiments, widths of the first contact electrode361and the second contact electrode362measured in one direction, may be greater than widths of the first electrode240and the second electrode250measured in the one direction. The first contact electrode361and the second contact electrode362may be disposed to cover side portions of the first electrode240and the second electrode250. However, the present disclosure is not limited thereto, and in some embodiments, the first contact electrode361and the second contact electrode362may be disposed to cover only one side portions of the first electrode240and the second electrode250. The contact electrodes361and362may include a conductive material. For example, the contact electrodes361and362may include ITO, IZO, ITZO, Al, or the like. However, the present disclosure is not limited thereto.

In some embodiments, as described above, the active material layer of the first semiconductor area2100or the second semiconductor area2200, that is, the driving transistor DT and the switching transistor ST, may include polycrystalline silicon or an oxide semiconductor. The contact electrodes361and362may also include an oxide semiconductor having conductivity in some embodiments. The contact electrodes361and362and the first active material layer126(seeFIG.4) of the driving transistor DT may be disposed in substantially the same layer, and in some example embodiments, the contact electrodes361and362and the first active material layer126may include the same material. In the display device10according to some example embodiments, the driving transistor DT of each pixel PX is disposed above the light-emitting element300, and the contact electrodes361and362in contact with the first active material layer126of the driving transistor DT and the light-emitting element300may be formed in the same process. Accordingly, the number of fabrication processes of the display device10may be reduced. A detailed description thereof will be made below with reference to other drawings.

A second conductive layer is disposed on the semiconductor layer. The second conductive layer may include a first gate electrode4100, a second gate electrode4200, a scan signal line4300, a second capacitor electrode4400, and the conductive line4600, which are disposed in the non-emission area NEA. The first gate electrode4100, the second gate electrode4200, and the second capacitor electrode4400may be disposed in the non-emission area NEA, and the scan signal line4300and the conductive line4600may be disposed over the non-emission area NEA and the emission area EMA.

The first gate electrode4100is disposed to overlap the first semiconductor area2100, the third semiconductor area2300, and the light-shielding layer260in the non-emission area NEA. The first gate electrode4100may form the gate electrode of the driving transistor DT in an area overlapping the first semiconductor area2100. In some embodiments, the first gate electrode4100may be in contact with the third semiconductor area2300through a third contact hole CNT3in an area overlapping the third semiconductor area2300, and the gate electrode of the driving transistor DT may be connected to one electrode of the switching transistor ST.

The scan signal line4300may transfer the scan signal to the switching transistor ST of each pixel PX. The scan signal line4300may extend in the first direction DR1, and the second gate electrode4200may be branched from the scan signal line4300and extend in the second direction DR2. The scan signal line4300extends in the first direction DR1at the upper side of the pixel PX in the drawing. The scan signal line4300may extend to another pixel PX positioned adjacent to one pixel PX in the first direction DR1.

The second gate electrode4200may be branched from at least a portion of the scan signal line4300in the second direction DR2. The second gate electrode4200may be disposed to overlap a portion of the second semiconductor area2200. The second gate electrode4200may form the gate electrode of the switching transistor ST. The scan signal line4300may transfer the scan signal to the switching transistor ST through the second gate electrode4200.

The second capacitor electrode4400may be disposed to overlap the first capacitor electrode1270in the non-emission area NEA. The second capacitor electrode4400and the first capacitor electrode1270may form the capacitor Cst of each pixel PX. In some embodiments, the second capacitor electrode4400may overlap one side of the second semiconductor area2200and may be in contact with the second semiconductor area2200through the fourth contact hole CNT4.

The conductive line4600may be disposed at the lower side of the pixel PX with respect to the center portion of the pixel PX and may also be disposed in another adjacent pixel in the first direction DR1by extending in the first direction DR1. The conductive line4600may overlap the second voltage line1230and may be in contact with the second voltage line1230through the fifth contact hole CNT5. In some embodiments, the conductive line4600may overlap the second electrode250and may be in contact with the second electrode250through a sixth contact hole CNT6. Accordingly, the second power voltage applied to the second voltage line1230may be transmitted to the second electrode250through the conductive line4600.

The second conductive layer may include one or more metals selected from among Mo, Al, Pt, Pd, Ag, Mg, Au, Ni, Nd, Ir, Cr, Ca, Ti, Ta, W, and Cu. The second conductive layer may be formed as a single-layer film or a multilayer film. For example, the second conductive layer may be formed in a stacked structure of Ti/Al/Ti, Mo/Al/Mo, Mo/AlGe/Mo, Ti/Cu, and the like.

A second insulating layer520is disposed on the second conductive layer and the contact electrodes361and362(e.g., seeFIG.4). The second insulating layer520may be disposed on the second conductive layer and the contact electrodes361and362to cover the second conductive layer and the contact electrodes361and362, and contact holes CNT7and CNT8passing through the second insulating layer520and exposing portions of the contact electrodes361and362or the first active material layer126may be formed in the second insulating layer520. A detailed description thereof will be made below.

A third conductive layer is disposed on the second insulating layer520. The driving transistor DT and the one electrode of the switching transistor ST are disposed in the third conductive layer. In the drawing, only an one electrode123of the driving transistor DT is illustrated, but the present disclosure is not limited thereto, and the third conductive layer may include an one electrode of the switching transistor ST.

The one electrode123of the driving transistor DT may be disposed to overlap one side of the first semiconductor area2100, that is, one side of the first active material layer126of the driving transistor DT in the non-emission area NEA, and may be disposed to overlap the first contact electrode361in the emission area EMA. The one electrode123may be in contact with a portion of the first semiconductor area2100through an eighth contact hole CNT8exposing a portion of the first semiconductor area2100by passing through the second insulating layer520. In some embodiments, the one electrode123may be in contact with a portion of the first contact electrode361through a seventh contact hole CNT7exposing a portion of the first contact electrode361by passing through the second insulating layer520. Thus, the driving transistor DT of the pixel PX may be electrically connected to one end portions of the first contact electrode361, the first electrode240, and the light-emitting element300.

Hereinafter, the structure of the display device10will be described in detail with reference to another drawing.

FIG.4is a cross-sectional view taken along lines IV-IV′ and V-V′ ofFIG.3, according to some embodiments of the present disclosure.

FIG.4illustrates cross sections of partial areas of the members illustrated inFIG.3to illustrate the arrangement of the driving transistor DT, the first electrode240, the second electrode250, and the light-emitting element300of each pixel PX. For example,FIG.4illustrates cross sections crossing a portion of the first semiconductor area2100and both end portions of one light-emitting element300in the non-emission area NEA. In some embodiments, some of the members illustrated inFIG.4have been given new reference numerals different from those inFIG.3for the convenience of description.

Referring toFIG.4, the display device10includes the substrate110, a plurality of banks210,220, and230disposed on the substrate110, the first electrode240, the second electrode250, the light-emitting element300, the first contact electrode361, the second contact electrode362, and the driving transistor DT. In some embodiments, the display device10may include the first insulating layer510and the second insulating layer520, which are disposed on the substrate110.

In some embodiments, the substrate110may be an insulating substrate. The substrate110may be made of an insulating material such as glass, quartz, a polymer resin, or the like. The substrate110may be a rigid substrate but may also be a flexible substrate that is bendable, foldable, rollable, or the like.

The plurality of banks210,220, and230may be disposed on the substrate110. The plurality of banks210,220, and230include a first bank210, a second bank220, and a third bank230, which are disposed to be spaced from each other. The first conductive layer, which will be described below, may be disposed above the plurality of banks210,220, and230. Although not illustrated in the drawing, the first bank210, the second bank220, and the third bank230may each have a shape extending in one direction, for example, in the second direction DR2, within each pixel PX.

The plurality of banks210,220, and230may each have a structure at least partially protruding from the substrate110. The banks210,220, and230may each protrude upward from a plane on which the light-emitting element300is disposed, and at least some portion of the protruding portions may have an inclination. The shape of each of the banks210,220, and230is not particularly limited. Because the banks210,220, and230each have inclined side surfaces protruding from the substrate110, the light emitted from the light-emitting element300may be reflected at the inclined side surfaces of each of the banks210,220, and230. As will be described below, when the electrodes240and250disposed on the banks210,220, and230include a material having high reflectance, the light emitted from the light-emitting element300may be reflected at the electrodes240and250, which are positioned on the inclined side surfaces of the banks210,220, and230to travel in an upward direction. For example, the banks210,220, and230may perform a function of a reflective partition wall that reflects the light emitted from the light-emitting element300in the upward direction. However, the present disclosure is not limited thereto. In some embodiments, the plurality of banks210,220, and230may include polyimide (PI), but the present disclosure is not limited thereto.

In some example embodiments, the plurality of banks210,220, and230may be made of a conductive material. In some embodiments, the banks210,220, and230may form one conductive layer, and the first conductive layer, for example, the first electrode240, the second electrode250, and the light-shielding layer260, which are disposed on the banks210,220, and230, may be integrated with the banks210,220, and230to form the one electrodes240and250or the light-shielding layer260. For example, when the third bank230includes a conductive material, for example, a light-shielding material such as a metal, the separate light-shielding layer260may be omitted, and the third bank230may perform a function of shielding light incident on the first active material layer126.

The light-shielding layer260, the first electrode240, and the second electrode250of the first conductive layer are disposed on the banks210,220, and230.

The light-shielding layer260may be disposed on the third bank230in the non-emission area NEA. The first electrode240and the second electrode250may be disposed on the first bank210and the second bank220, respectively, in the emission area EMA. Each of the light-shielding layer260, the first electrode240, and the second electrode250may have a width that is greater than that of each of the banks210,220, and230, and at least a portion thereof may be disposed on the banks210,220, and230, and another portion thereof may be disposed on the substrate110.

The first insulating layer510may be disposed on the first electrode240, the second electrode250, and the light-shielding layer260. In some example embodiments, the first insulating layer510may be disposed to expose flat top surfaces of the first electrode240and the second electrode250, for example, at least portions thereof disposed on the top surfaces of the first bank210and the second bank220. On the other hand, the first insulating layer510may be disposed to cover a top surface of the light-shielding layer260. Unlike the first electrode240and the second electrode250, the entire surface of the light-shielding layer260may be covered by the first insulating layer510without exposing the top surface thereof. The first active material layer126of the driving transistor DT may be disposed on the light-shielding layer260with the first insulating layer510therebetween.

The first insulating layer510may protect the first electrode240and the second electrode250and, concurrently (e.g., simultaneously), insulate the first electrode240from the second electrode250. In some embodiments, the light-emitting element300disposed on the first insulating layer510may be prevented or protected from being damaged by being in direct contact with other members. However, the shape and structure of the first insulating layer510are not limited thereto.

In some example embodiments, the first insulating layer510may be formed such that a portion thereof disposed between the first electrode240and the second electrode250has a flat top surface. The flat top surface of the first insulating layer510extends in one direction toward the first electrode240and the second electrode250, and the first insulating layer510may also be disposed in areas in which the electrodes240and250overlap the inclined side surfaces of the first bank210and the second bank220, respectively. Each of the contact electrodes361and362may be in contact with the exposed areas of the first electrode240and the second electrode250and may be smoothly in contact with an end portion of the light-emitting element300on the flat top surface of the first insulating layer510.

However, the present disclosure is not limited thereto. A step may be formed in the portion of the first insulating layer510, which is disposed between the first electrode240and the second electrode250, such that a portion of the top surface of the first insulating layer510is recessed. The first insulating layer510may include an inorganic insulating material, and the portion of the top surface of the first insulating layer510, which is disposed to cover the first electrode240and the second electrode250, may be recessed due to the step formed by the electrodes240and250disposed below the first insulating layer510. The light-emitting element300may be disposed on the first insulating layer510between the first electrode240and the second electrode250, and an empty space may be formed between the light-emitting element300and the recessed top surface of the first insulating layer510. The light-emitting element300may be disposed in a state of being partially separated from the top surface of the first insulating layer510. The empty space between the top surface of the first insulating layer510and the light-emitting element300may be filled with a material of the second insulating layer520disposed on the light-emitting element300.

The first active material layer126of the driving transistor DT, the light-emitting element300, and the contact electrodes361and362are disposed on the first insulating layer510.

The light-emitting element300may be disposed on the first insulating layer510between the electrodes240and250. However, the present disclosure is not limited thereto, and, although not shown in the drawing, at least some of the light-emitting elements300disposed in the pixel PX may be disposed in an area except for the area between the electrodes240and250. In some embodiments, the light-emitting element300may be disposed such that at least portion thereof overlaps the electrodes240and250. Both end portions of the light-emitting element300may be disposed on the end portion of the first electrode240and the end portion of the second electrode250, which are facing each other.

The light-emitting element300may include a plurality of layers arranged along a direction parallel to the substrate110. The light-emitting element300of the display device10according to some example embodiments may have a shape extending in one direction and have a structure in which a plurality of semiconductor layers are sequentially disposed in one direction. In the light-emitting element300, a first semiconductor layer310, the active layer330, a second semiconductor layer320, and an electrode layer370may be sequentially disposed in one direction, and an insulating film380may surround outer surfaces of the first semiconductor layer310, the active layer330, the second semiconductor layer320, and the electrode layer370(e.g., seeFIG.5). The light-emitting element300disposed in the display device10may be disposed such that an extending one direction thereof is parallel to the substrate110, and the plurality of semiconductor layers included in the light-emitting element300may be sequentially arranged along a direction parallel to a top surface of the substrate110. However, the present disclosure is not limited thereto. In some embodiments, when the light-emitting element300has a different structure, the plurality of semiconductor layers may be arranged along a direction perpendicular to the substrate110. A detailed description of the light-emitting element300will be made below with reference to other drawings.

Also, one end portion of the light-emitting element300may be in contact with the first contact electrode361and the other end portion thereof may be in contact with the second contact electrode362. According to some example embodiments, because the insulating film380is not formed on the extending end surfaces of the light-emitting element300in one direction and the extending end surfaces thereof are exposed, the exposed end surfaces may be in contact with the first contact electrode361and the second contact electrode362, which will be described below. However, the present disclosure is not limited thereto. In some embodiments, at least a portion of the insulating film380is removed from the light-emitting element300, and the insulating film380is removed such that side surfaces of both end portions of the light-emitting element300may be partially exposed. In some embodiments, the exposed side surfaces of the light-emitting element300may be in contact with the first contact electrode361and the second contact electrode362. However, the present disclosure is not limited thereto.

In some embodiments, a third insulating layer530_3(seeFIG.20) may be further disposed on the light-emitting element300. The third insulating layer530_3may be disposed to expose both end portions of the light-emitting elements300and may fix the light-emitting elements300so that the light-emitting elements300do not move during a fabricating process of the display device10. A description thereof will be made below.

The first active material layer126of the driving transistor DT is disposed on the first insulating layer510overlapping the light-shielding layer260. The first active material layer126may be an area of the first semiconductor area2100that overlaps the light-shielding layer260. The first active material layer126may include a first conductive area126a, a second conductive area126b, and a channel area126c. The channel area126cmay be disposed between the first conductive area126aand the second conductive area126b. According to some example embodiments, the first active material layer126may include an oxide semiconductor. In some embodiments, the oxide semiconductor may be an oxide semiconductor containing indium (In). In some example embodiments, the oxide semiconductor may include ITO, IZO, indium-gallium oxide (IGO), indium-zinc-tin oxide (IZTO), indium-gallium-tin oxide (IGTO), indium-gallium-zinc-tin oxide (IGZTO), or the like. However, the present disclosure is not limited thereto. The first conductive area126aand the second conductive area126bmay be areas in which at least a portion of the first active material layer126becomes conductive. Accordingly, the first conductive area126aand the second conductive area126bmay be source or drain areas of the first active material layer126. The second conductive area126bmay be a drain area when the first conductive area126ais a source area, and the second conductive area126bmay be a source area when the first conductive area126ais a drain area. However, the present disclosure is not limited thereto.

However, the first active material layer126is not necessarily limited to the above description. In some example embodiments, the first active material layer126may include polycrystalline silicon. In some embodiments, the first conductive area126amay be a first doped area, and the second conductive area126bmay be a second doped area. The polycrystalline silicon may be formed by crystallizing amorphous silicon. Non-limiting examples of the crystallization method may include a rapid thermal annealing (RTA) method, a solid phase crystallization (SPC) method, an excimer laser annealing (ELA) method, a metal-induced crystallization (MILC) method, a sequential lateral solidification (SLS) method, and the like, but the present disclosure is not limited thereto. As another example, the first active material layer126may include single-crystalline silicon, low-temperature polycrystalline silicon, amorphous silicon, or the like.

In some embodiments, the first active material layer126or the first semiconductor area2100may be electrically connected to the first voltage line1220. A pad electrode PAD may be disposed on the first voltage line1220exposed through the second contact hole CNT2, and the first active material layer126of the driving transistor DT may be in contact with the pad electrode PAD. Thus, the driving transistor DT may be electrically connected to the first voltage line1220.

A gate insulating layer150and a gate electrode121of the driving transistor DT are disposed on the first active material layer126. The gate electrode121may overlap the channel area126cof the first active material layer126with the gate insulating layer150therebetween. As described above, the gate electrode121may be the first gate electrode4100of the third conductive layer.

The contact electrodes361and362are disposed on the first electrode240and the second electrode250, respectively. The first contact electrode361is disposed on the first electrode240, and the second contact electrode362is disposed on the second electrode250. In some embodiments, at least portions of the contact electrodes361and362are disposed on the first insulating layer510. The first contact electrode361may be in contact with the exposed area of the first electrode240on the first bank210, and the second contact electrode362may be in contact with the exposed area of the second electrode250on the second bank220. As described above, the first contact electrode361and the second contact electrode362may be in contact with at least one end portion of the light-emitting element300and electrically connected to the first electrode240or the second electrode250to receive an electrical signal.

The second insulating layer520is disposed on the contact electrodes361and362and the gate electrode121of the driving transistor DT. The second insulating layer520may be disposed on the entire surface of the substrate110and may be disposed to cover the contact electrodes361and362, the gate electrode121of the driving transistor DT, and the light-emitting element300. In some embodiments, as described above, the seventh contact hole CNT7exposing a portion of the first contact electrode361by passing through the second insulating layer520, and the eighth contact hole CNT8exposing one side of the first active material layer126may be formed on the second insulating layer520. The one electrode123of the driving transistor DT may be disposed on the second insulating layer520and may be in contact with the first doped area126a, which is one side of the first active material layer126, and the first contact electrode361through the contact holes CNT7and CNT8, respectively.

A passivation layer550may be disposed on the second insulating layer520and the one electrode123of the driving transistor DT. The passivation layer550may serve to protect members disposed on the substrate110from an external environment.

The first insulating layer510, the second insulating layer520, and the passivation layer550, which are described above, may each include an inorganic insulating material or an organic insulating material. In some example embodiments, the first insulating layer510, the second insulating layer520, and the passivation layer550may each include an inorganic insulating material such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), aluminum oxide (Al2O3), aluminum nitride (AlN), or the like. Further, the first insulating layer510, the second insulating layer520, and the passivation layer550may each include acrylic resin, epoxy resin, phenol resin, polyamide resin, polyimide resin, unsaturated polyester resin, polyphenylene resin, polyphenylene sulfide resin, benzocyclobutene, cardo resin, siloxane resin, silsesquioxane resin, polymethylmethacrylate, polycarbonate, polymethylmethacrylate-polycarbonate synthetic resin, or the like as an organic insulating material. However, the present disclosure is not limited thereto.

In some embodiments, an encapsulation layer EN may be disposed on the passivation layer550. In some example embodiments, the encapsulation layer EN may be a thin-film encapsulation layer including at least one encapsulation film. For example, the encapsulation layer EN may include a first inorganic film, an organic film, and a second inorganic film. The first inorganic film and the second inorganic film may each include silicon nitride, silicon oxide, or silicon oxynitride. The organic film may include an organic insulation material such as acryl resin, epoxy resin, phenolic resin, polyamide resin, polyimide resin, unsaturated polyester resin, polyphenylene ether resin, polyphenylene sulfide resin, benzocyclobutene (BCB), or the like.

FIG.5is a schematic view of the light-emitting element according to some example embodiments of the present disclosure.

The light-emitting element300may be a light-emitting diode, and in some embodiments, may be an inorganic light-emitting diode having a size of a micrometer unit or a nanometer unit and made of an inorganic material. The inorganic light-emitting diode may be aligned between two electrodes in which polarity is formed by forming an electric field in a specific direction between the two electrodes facing each other. The light-emitting element300may be aligned between two electrodes due to an electric field formed on the two electrodes.

The light-emitting element300according to some example embodiments may have a shape extending in one direction. The light-emitting element300may have a shape of a rod, a wire, a tube, or the like. In some example embodiments, the light-emitting element300may have a cylindrical shape or a rod shape. However, the shape of the light-emitting element300is not limited thereto, and the light-emitting element300may have a shape of a cube, a rectangular parallelepiped, a polygonal pillar such as a hexagonal pillar or the like or have a shape which extends in one direction and has a partially inclined outer surface. Thus, the light-emitting element300may have various shapes. A plurality of semiconductors included in the light-emitting element300, which will be described below, may have a structure in which the semiconductors are sequentially arranged or stacked along the one direction.

The light-emitting element300may include a semiconductor layer doped with an arbitrary conductive-type (for example, p-type or n-type) impurity. The semiconductor layer may receive an electric signal applied from an external power source and emit light in a specific wavelength range.

The light-emitting element300according to some example embodiments may emit light in a specific wavelength range. In some example embodiments, the active layer330may emit blue light having a central wavelength band ranging from 450 nm to 495 nm. However, the central wavelength band of the blue light is not limited to the above-described range, and it should be understood that the central wavelength band includes all wavelength ranges that can be recognized as a blue color in the art. Further, the light emitted from the active layer330of the light-emitting element300is not limited thereto, and the light may be green light having a central wavelength band ranging from 495 nm to 570 nm or red light having a central wavelength band ranging from 620 nm to 750 nm. Hereinafter, an example in which the light-emitting element300emits blue light will be described.

Referring toFIG.5, the light-emitting element300may include a semiconductor core and the insulating film380surrounding the semiconductor core, and the semiconductor core of the light-emitting element300may include the first semiconductor layer310, the second semiconductor layer320, and the active layer330. For example, the light-emitting element300according to some example embodiments may further include the electrode layer370disposed on one surface of the first semiconductor layer310or the second semiconductor layer320.

The first semiconductor layer310may be an n-type semiconductor. As an example, when the light-emitting element300emits light in a blue wavelength range, the first semiconductor layer310may include a semiconductor material having a chemical formula of AlxGayIn1-x-yN (0≤x≤1, 0≤y≤1, and 0≤x+y≤1). For example, the semiconductor material may be one or more from among AlGaInN, GaN, AlGaN, InGaN, AlN, and InN that are doped with an n-type impurity. The first semiconductor layer310may be doped with an n-type dopant. As an example, the n-type dopant may be Si, Ge, Sn, or the like. In some example embodiments, the first semiconductor layer310may be n-GaN doped with n-type Si. A length of the first semiconductor layer310may range from 1.5 μm to 5 μm, but the present disclosure is not limited thereto.

The second semiconductor layer320is disposed on the active layer330that will be described below. The second semiconductor layer320may be a p-type semiconductor. As an example, when the light-emitting element300emits light in a blue or green wavelength range, the second semiconductor layer320may include a semiconductor material having a chemical formula of AlxGayIn1-x-yN (0≤x≤1, 0≤y≤1, and 0≤x+y≤1). For example, the semiconductor material may be one or more from among AlGaInN, GaN, AlGaN, InGaN, AlN, and InN that are doped with a p-type impurity. The second semiconductor layer320may be doped with a p-type dopant. As an example, the p-type dopant may be Mg, Zn, Ca, selenium (Se), barium (Ba), or the like. In some example embodiments, the second semiconductor layer320may be p-GaN doped with p-type Mg. A length of the second semiconductor layer320may range from 0.05 μm to 0.10 μm, but the present disclosure is not limited thereto.

In some embodiments, the first semiconductor layer310and the second semiconductor layer320are illustrated in the drawing as being formed of one layer, but the present disclosure is not limited thereto. According to some example embodiments, the first semiconductor layer310and the second semiconductor layer320may further include a greater number of layers, e.g., a clad layer or a tensile strain barrier reducing (TSBR) layer according to a material of the active layer330. A description thereof will be made below with reference to other drawings.

The active layer330is disposed between the first semiconductor layer310and the second semiconductor layer320. The active layer330may include a material having a single or multiple quantum well structure. When the active layer330includes a material having a multiple quantum well structure, the active layer330may have a structure in which a quantum layer and a well layer are alternately stacked. The active layer330may emit light due to a combination of electron-hole pairs in response to electrical signals applied through the first semiconductor layer310and the second semiconductor layer320. As an example, when the active layer330emits light in a blue wavelength range, the active layer330may include a material such as AlGaN, AlGaInN, or the like. For example, when the active layer330has a multiple quantum well structure in which a quantum layer and a well layer are alternately stacked, the quantum layer may include a material such as AlGaN or AlGaInN, and the well layer may include a material such as GaN or AlInN. In some example embodiments, the active layer330includes AlGaInN as a quantum layer and AlInN as a well layer. As described above, the active layer330may emit blue light having a central wavelength band ranging from 450 nm to 495 nm.

However, the present disclosure is not limited thereto, and the active layer330may have a structure in which a semiconductor material having large bandgap energy and a semiconductor material having small bandgap energy are alternately stacked or include other group III or group V semiconductor materials according to the wavelength range of emitted light. The light emitted by the active layer330is not limited to light in a blue wavelength band, and the active layer330may also emit light in a red or green wavelength band in some embodiments. A length of the active layer330may range from 0.05 μm to 0.10 μm, but the present disclosure is not limited thereto.

In some embodiments, the light emitted from the active layer330may be emitted to not only an outer surface of the light-emitting element300in a lengthwise direction but also the both side surfaces of the light-emitting element300. Directivity of the light emitted from the active layer330is not limited to one direction.

The electrode layer370may be an ohmic contact electrode. However, the present disclosure is not limited thereto, and the electrode layer370may be a Schottky contact electrode. The light-emitting element300may include at least one electrode layer370. Although the light-emitting element300is illustrated inFIG.5as including a single electrode layer370, the present disclosure is not limited thereto. In some embodiments, the light-emitting element300may include a greater number of electrode layers370, or the electrode layer370may be omitted. The description of the light-emitting element300, which will be made below, may be identically applied even when the number of electrode layers370is varied or another structure is further included.

In the display device10according to some example embodiments, when the light-emitting element300is electrically connected to the electrode or the contact electrode, the electrode layer370may decrease the resistance between the light-emitting element300and the electrode or between the light-emitting element300and the contact electrode (e.g.,361,362as shown inFIG.4). The electrode layer370may include a conductive metal. For example, the electrode layer370may include at least one from among Al, Ti, In, Au, Ag, ITO, IZO, and ITZO. Further, the electrode layer370may include a semiconductor material doped with an n-type or p-type impurity. The electrode layer370may include the same material or different materials. A length of the electrode layer370may range from 0.02 μm to 0.01 μm, but the present disclosure is not limited thereto.

The insulating film380is disposed to surround some of the outer surfaces (e.g., side surfaces) of the semiconductor core and the electrode layer370. In some example embodiments, the insulating film380may be disposed to surround at least the outer surface of the active layer330and may extend in one direction in which the light-emitting element300extends. The insulating film380may serve to protect the members. For example, the insulating film380may be formed to surround side surface portions of the members and to expose both end portions of the light-emitting element300in the lengthwise direction (e.g., the top surface of the electrode layer370may be devoid of the insulating film380and may be exposed).

In the drawing, the insulating film380is illustrated as being formed to extend in the lengthwise direction of the light-emitting element300to cover from a body portion of the first semiconductor layer310to a side surface of the electrode layer370, but the present disclosure is not limited thereto. Because the insulating film380covers only the outer surfaces of some semiconductor layers including the active layer330or covers only a portion of the outer surface of the electrode layer370, the outer surface of the electrode layer370may be partially exposed. In some embodiments, a top surface of the insulating film380may be formed to be rounded in cross section in an area adjacent to at least one end portion of the light-emitting element300.

The insulating film380may include an insulating material such as SiOx, SiNx, SiOxNy, AlN, Al2O3, or the like. Accordingly, it is possible to prevent (or reduce the chance of) an electrical short circuit which may occur when the active layer330is in direct contact with an electrode through which an electrical signal is transmitted to the light-emitting element300. Further, because the insulating film380protects the outer surface of the light-emitting element300including the active layer330, it is possible to prevent or reduce degradation in light emission efficiency.

Further, in some example embodiments, an outer surface of the insulating film380may be surface treated. During the fabrication of the display device10, the light-emitting elements300may be aligned by being injected onto the electrodes in a state of being dispersed in a predetermined (or set) ink. Here, in order to allow the light-emitting element300to maintain the dispersed state in the ink without being agglomerated with another adjacent light-emitting element300, the surface of the insulating film380may be hydrophobically or hydrophilically treated.

The insulating film380may protect the semiconductor core including at least the active layer330of the light-emitting element300. As described above, during the fabricating process of the light-emitting element300, and during the fabricating process of the display device10, the insulating film380may be partially etched to have a smaller thickness. When the insulating film380has a small thickness, the insulating film380may be etched and removed during the fabricating process, or the semiconductor core, particularly the active layer330, may be damaged. In order to prevent or reduce the possibility of damage of the active layer330, the insulating film380of the light-emitting element300according to some example embodiments may have a thickness greater than or equal to a predetermined level (e.g., a set level). In some example embodiments, a thickness of the insulating film380may range from 10 nm to 1.0 μm, but the present disclosure is not limited thereto. In some embodiments, the thickness of the insulating film380may be about 40 nm.

The light-emitting element300may have a length ranging from 1 μm to 10 μm or from 2 μm to 6 μm, and in some embodiments from 3 μm to 5 μm. In some embodiments, a diameter of the light-emitting element300may range from 300 nm to 700 nm, and an aspect ratio of the light-emitting element300may range from 1.2 to 100. However, the present disclosure is not limited thereto, and the plurality of light-emitting elements300included in the display device10may have different diameters according to a composition difference of the active layer330. In some embodiments, the diameter of the light-emitting element300may have a range of about 600 nm.

In the display device10according to some example embodiments, each pixel PX may include the emission area EMA in which the light-emitting elements300are disposed and non-emission area NEA in which the circuit elements, for example, the driving transistor DT and the switching transistor ST, are disposed. The driving transistor DT is disposed above the light-emitting element300so as not to overlap each other so that the light emitted from the light-emitting element300may travel in an upward or downward direction with respect to the substrate110. Accordingly, the display device10may have a top emission structure or a bottom emission structure depending on the direction of the light emitted from the light-emitting element300.

In some embodiments, in the display device10, the contact electrodes361and362and the first active material layer126of the driving transistor DT are disposed on the first insulating layer510. For example, the first active material layer126of the driving transistor DT may be disposed on the same layer as the contact electrodes361and362. In some example embodiments, the contact electrodes361and362may include the same material as the first active material layer126, and the contact electrodes361and362and the first active material layer126may be generated in the same process during the fabricating process of the display device10. Accordingly, the number of fabricating processes of the display device10may be reduced. This will be described in detail below with reference to other example embodiments.

Hereinafter, the process of fabricating the display device10will be described with reference to other drawings.

FIGS.6-13are cross-sectional views illustrating the process of fabricating the display device according to some example embodiments of the present disclosure.

Referring toFIGS.6and7, first, a substrate110is prepared, and a plurality of banks210,220, and230disposed on the substrate110, and a first electrode240, a second electrode250, and a light-shielding layer260, which are disposed on the plurality of banks210,220, and230, are formed. The banks may include a first bank210, a second bank220, and a third bank230. The arrangement of the first electrode240, the second electrode250, and the light-shielding layer260is the same as described above, and thus a detailed description thereof will be omitted, as one of the ordinary skill in the art would be able to appreciate from the detailed description ofFIG.4. The above-described members may be formed by patterning a metal, an inorganic material, an organic material, or the like by performing a typical mask process.

In some embodiments, in the drawings, the banks210,220, and230, the electrodes240and250, and the light-shielding layer260are illustrated as being formed on the substrate110in a separate process, but the present disclosure is not limited thereto. In some example embodiments, the banks210,220, and230may be omitted, and the electrodes240and250and the light-shielding layer260may include a plurality of layers such that at least portion thereof have a protruding shape.

Subsequently, referring toFIG.8, a first insulating layer510is formed on the electrodes240and250and the light-shielding layer260, and light-emitting elements300are aligned between the first electrode240and the second electrode250. The first insulating layer510may be formed through a process of forming the first insulating layer510above the substrate110to cover top surfaces of the first electrode240and the second electrode250and then etching at least portion of the first insulating layer510after the light-emitting elements300are aligned. The process of forming the first insulating layer510may be performed through a patterning process using a mask known to a person skilled in the art.

The light-emitting elements300may be aligned between the electrodes240and250by spraying an ink including the light-emitting element300on the first electrode240and the second electrode250and applying an electrical signal to the first electrode240and the second electrode250. When the electrical signal is applied to the first electrode240and the second electrode250to which the ink is sprayed, an electric field is generated in the ink, and the positions and orientations of the light-emitting elements300are changed by the electric field so that the light-emitting elements300may be mounted between the electrodes240and250. Here, the light-emitting elements300may be aligned such that the extending directions thereof become constant according to the direction of the electric field. Subsequently, the solvent of the ink may be removed to dispose the light-emitting elements300between the electrodes240and250.

Next, referring toFIGS.9and10, contact electrodes361and362are formed on the first electrode240and the second electrode250. In the drawings, it is illustrated that a second contact electrode362is formed first, and then a first contact electrode361is formed, but the present disclosure is not limited thereto. The first and second contact electrodes361and362may be formed in the same process, or the first contact electrode361may be formed first.

Subsequently, referring toFIG.11, a first active material layer126is formed on the first insulating layer510that overlaps the light-shielding layer260, and a gate insulating layer150and a gate electrode121are formed on an upper portion of the first active material layer126.

The first contact electrode361and the second contact electrode362may be disposed on the same layer as the first active material layer126of a driving transistor DT as described above. When the contact electrodes361and362and the first active material layer126are made of different materials, the contact electrodes361and362and the first active material layer126may be formed in different processes as illustrated in the drawings. However, when the contact electrodes361and362and the first active material layer126include the same material, for example, an oxide semiconductor, the contact electrodes361and362and the first active material layer126may be formed in the same process. For example, in the process of forming a conductive area and a channel area in the first active material layer126, the contact electrodes361and362having the oxide semiconductor may also be concurrently (e.g., simultaneously) conductive. In some embodiments, the process of forming the contact electrodes361and362and the first active material layer126may be performed in one process, and the number of fabricating processes of the display device10may be reduced.

Next, referring toFIGS.12-14, a second insulating layer520and an one electrode123of the driving transistor DT are formed, and a passivation layer550and an encapsulation layer EN, which are disposed above the second insulating layer520and the one electrode123, are formed, thereby fabricating the display device10.

In the display device10according to some example embodiments, the driving transistor DT, which is disposed in a non-emission area NEA, is disposed above the light-emitting element300that is disposed in an emission area EMA. Accordingly, the contact electrodes361and362in contact with the light-emitting element300may be disposed on the same layer as the first active material layer126of the driving transistor DT, and the number of fabricating processes may be reduced in the process of forming the contact electrodes361and362and the first active material layer126.

Hereinafter, various example embodiments of the display device10will be described.

FIG.14is a partial cross-sectional view of a display device according to some example embodiments of the present disclosure.

Referring toFIG.14, in a display device10_1according to some example embodiments, at least one of contact electrodes361_1and362_1may include an oxide semiconductor and may include the same material as a first active material layer126of a driving transistor DT. In some embodiments, the contact electrodes361_1and362_1including the oxide semiconductor may be formed in the same process as the first active material layer126and thus may become conductive together with a first conductive area126a. For example, the contact electrodes361_1and362_1may include the same material as the first conductive area126aof the first active material layer126. The present example embodiment differs from the example embodiment described with reference toFIG.4in that the contact electrodes361_1and362_1include the same material as the first active material layer126. Hereinafter, repeated descriptions will be omitted and a description will be made to focus on a difference, as one of the ordinary skill in the art would be able to appreciate from the detailed description of the previous drawings.

In the display device10_1ofFIG.14, a first contact electrode361_1includes an oxide semiconductor, and thus the first contact electrode361_1may include the same material as the first conductive area126aof the first active material layer126. The contact electrodes361_1and362_1and the first active material layer126are disposed on the first insulating layer510and thus may be disposed on substantially the same layer. During a fabricating process of the display device10_1, a contact electrode including the same material as the first active material layer126from among the contact electrodes361_1and362_1may be formed concurrently (e.g., simultaneously) with the first active material layer126. For example, when the first contact electrode361_1includes the same material as the first active material layer126, the first contact electrode361_1and the first active material layer126may be concurrently (e.g., simultaneously) formed before or after the process of forming a second contact electrode362_1is performed. Accordingly, one operation may be omitted in the process of forming the contact electrodes361_1and362_1, and the number of fabricating processes of the display device10_1may be reduced.

FIGS.15and16are cross-sectional views illustrating a process of fabricating the display device ofFIG.14, according to some embodiments of the present disclosure.

First, referring toFIG.15, a first insulating layer510is formed on each of electrodes240and250and a light-shielding layer260, and then an oxide semiconductor forming a second contact electrode362_1and a first contact electrode361′_1and a first active material layer126is formed. Subsequently, referring toFIG.16, a portion of the oxide semiconductor becomes conductive to form the first contact electrode361_1disposed on the first electrode240and conductive areas126aand126bof the first active material layer126. In some example embodiments, the number of fabricating processes in the operation of forming the first contact electrode361_1, the second contact electrode362_1, and the first active material layer126may be reduced as compared with the operation illustrated inFIGS.9-11. The number of fabricating processes may be reduced by forming the second contact electrode362_1including other materials first, and then forming the first contact electrode361_1and the first active material layer126in the same process.

In some embodiments, in the second contact electrode362, when the oxide semiconductor is included in the same manner as the first contact electrode361, the number of fabricating processes may be further reduced.

FIG.17is a partial cross-sectional view of a display device according to some example embodiments of the present disclosure.FIGS.18and19are cross-sectional views illustrating a process of fabricating the display device ofFIG.17.

Referring toFIG.17, in a display device10_2according to some example embodiments, a first contact electrode361_2and a second contact electrode362_2may each include an oxide semiconductor and may include the same material as a first active material layer126of a driving transistor DT. The example embodiment ofFIG.17differs from the example embodiment described with reference toFIG.14in that the second contact electrode362_2also includes the same material as the conductive areas126aand126bof the first active material layer126.

Referring toFIGS.18and19, a first insulating layer510is formed on electrodes240and250and a light-shielding layer260, and then the oxide semiconductor is formed on the electrodes240and250and the light-shielding layer260. Subsequently, the oxide semiconductor becomes conductive to form conductive areas126aand126bof the first active material layer126, the first contact electrode361_2, and the second contact electrode362_2. In the example embodiment ofFIG.17, the number of fabricating processes in the operation of forming the first contact electrode361_2, the second contact electrode362_2, and the first active material layer126may be reduced as compared with the operation illustrated inFIGS.15and16. The first contact electrode361_2, the second contact electrode362_2, and the first active material layer126may all be formed in the same process by including the same material so that the number of fabricating processes of the display device10_2may be further reduced. Hereinafter, repeated descriptions will be omitted, as one of the ordinary skill in the art would be able to appreciate from the detailed description of the previous drawings.

FIG.20is a partial cross-sectional view of a display device according to some example embodiments of the present disclosure.

Referring toFIG.20, a display device10_3according to some example embodiments may further include a third insulating layer530_3disposed on a light-emitting element300. The example embodiment ofFIG.20differs from the example embodiment described with reference toFIG.4in that the display device10_3further includes the third insulating layer530_3. Hereinafter, repeated descriptions will be omitted and a description will be made to focus on a difference.

The third insulating layer530_3may be partially disposed on the light-emitting element300disposed between a first electrode240and a second electrode250. The third insulating layer530_3may be disposed to partially surround an outer surface of the light-emitting element300and thus may protect the light-emitting element300and may also serve to fix the light-emitting element300during the fabricating process of the display device10_3. According to some example embodiments, the third insulating layer530_3may be disposed on the light-emitting element300and may expose one end portion and the other end portion of the light-emitting element300. The exposed one end portion and the other end portion of the light-emitting element300may be in contact with contact electrodes361_3and362_3so that the light-emitting element300may receive an electrical signal from each of electrodes240and250. The contact electrodes361_3and362_3according to the some example embodiments may be in contact with the third insulating layer530_3. Such a shape of the third insulating layer530_3may be formed by a patterning process using a material forming the third insulating layer530_3by using a typical mask process. A mask to form the third insulating layer530_3has a width less than a length of the light-emitting element300, and a material forming the third insulating layer530_3is patterned to expose both end portions of the light-emitting element300. However, the present disclosure is not limited thereto.

Further, in some example embodiments, a portion of the material of the third insulating layer530_3may be disposed between a bottom surface of the light-emitting element300and a first insulating layer510. The third insulating layer530_3may be formed to fill a space between the first insulating layer510and the light-emitting element300, which is formed during the process of fabricating the display device10_3. Accordingly, the third insulating layer530_3may be formed to partially surround the outer surface of the light-emitting element300. However, the present disclosure is not limited thereto.

The third insulating layer530_3may be disposed to extend in the second direction DR2between the first electrode240and the second electrode250in a plan view. As an example, in a plan view, the third insulating layer530_3may have an island shape or a linear shape on a substrate110.

FIGS.21and22are cross-sectional views illustrating a process of fabricating the display device ofFIG.20, according to some embodiments of the present disclosure.

Referring toFIG.21, a first insulating layer510is formed, and light-emitting elements300are aligned between a first electrode240and a second electrode250, and then a third insulating layer530_3is formed on the light-emitting elements300. Because the third insulating layer530_3is disposed to cover the light-emitting elements300aligned between the electrodes240and250, the light-emitting elements300may be prevented (or protected) from being moved in a subsequent process. Such a shape of the third insulating layer530_3may be formed by forming a material constituting the third insulating layer530_3so as to cover all the members disposed on a substrate110and then partially patterning the material. The third insulating layer530_3may be formed before a first contact electrode361_3and a second contact electrode362_3are formed and thus may be disposed therebelow. For example, according to the example embodiment ofFIG.21, the third insulating layer530_3may be disposed between the contact electrodes361_3and362_3and the light-emitting element300.

Subsequently, referring toFIG.22, after forming the third insulating layer530_3, the contact electrodes361_3and362_3disposed on the electrodes240and250are formed. A description thereof is the same as described above.

In some embodiments, banks210,220, and230disposed on the substrate110may each have inclined surfaces to reflect light emitted from the light-emitting element300. However, in some example embodiments, when the electrodes240and250and a light-shielding layer260are each formed of a plurality of metal layers, another metal layer disposed on one metal layer may have inclined surfaces, and the banks210,220, and230may be omitted.

FIG.23is a partial cross-sectional view of a display device according to some example embodiments of the present disclosure.

Referring toFIG.23, in a display device10_4according to some example embodiments, banks210,220, and230are omitted, and a first electrode240_4, a second electrode250_4, and a light-shielding layer260_4may include a plurality of metal layers. The metal layers may include first metal layers241_4,251_4, and261_4and second metal layers242_4,252_4, and262_4disposed on the first metal layers241_4,251_4, and261_4. A first-1 metal layer241_4and a second-1 metal layer242_4may form one first electrode240_4, a first-2 metal layer251_4and a second-2 metal layer252_4may form one second electrode250_4, and a first-3 metal layer261_4and a second-3 metal layer262_4may form one light-shielding layer260_4. Because descriptions of the first-1 metal layer241_4and the second-1 metal layer242_4of the first electrode240_4may be similarly applied to the second electrode250_4and the light-shielding layer260_4, only the embodiment of the first electrode240_4will be described as an example below.

The first-1 metal layer241_4is disposed directly on a substrate110, and the second-1 metal layer242_4is disposed on the first-1 metal layer241_4. According to some example embodiments, a width of the first-1 metal layer241_4may be greater than a width of the second-1 metal layer242_4, and a thickness of the second-1 metal layer242_4may be greater than a thickness of the first-1 metal layer241_4. The second-1 metal layer242_4may have a shape protruding upward with respect to a top surface of the first-1 metal layer241_4and may include sloped surfaces (e.g., side surfaces) to reflect light emitted from light-emitting elements300in an upward direction like the banks210,220, and230.

During a process of fabricating the display device10_4, the light-emitting elements300may be aligned by applying an alignment signal through the first metal layers241_4,251_4, and261_4, and while driving the display device10_4, a driving signal may be transmitted through the second metal layers242_4,252_4, and262_4. For example, in the second electrode250_4, the conductive line4600(seeFIG.3) may be in contact with the second-2 metal layer252_4of the second electrode250_4, and a second power voltage VSS may be transmitted through the second-2 metal layer252_4, so that the second power voltage VSS may be transmitted to the second electrode250_4through the conductive line4600. Likewise, a first contact electrode361_4and a second contact electrode362_4may be in contact with the second-1 metal layer242_4and the second-2 metal layer252_4, respectively, so that an electrical signal may be transmitted to the light-emitting element300.

The shapes of the first metal layer and the second metal layer may be formed through an etch-back process of disposing a material forming the first metal layer and the second metal layer on the entire surface of the substrate110and then concurrently (e.g., simultaneously) etching the first metal layer and the second metal layer. The first metal layer and the second metal layer include materials having different etch selectivity, and the second metal layer is first etched to form inclined surfaces, and then the first metal layer is etched to form the electrodes240_4and250_4and the light-shielding layer260_4. Detailed descriptions thereof will be omitted, as one of the ordinary skill in the art would be able to appreciate from the detailed description of the previous drawings.

In some embodiments, the display device10_4may further include various members disposed to overlap the light-emitting element300.

FIGS.24-27are partial cross-sectional views of display devices according to some example embodiments of the present disclosure.

Referring toFIG.24, a display device10_5according to some example embodiments may further include a color filter layer CF_5disposed on a light-emitting element300. The color filter layer CF_5may be disposed on a second insulating layer520so that light emitted from the light-emitting element300is incident and may be disposed at a position overlapping the light-emitting element300in a thickness direction. The color filter layer CF_5may selectively transmit light of any first color and may block light of colors other than the first color from being transmitted. In some example embodiments, the color filter layer CF_5may include a colorant such as a dye or pigment of the first color. In the present disclosure, the term colorant may refer to a dye or a pigment or both of a dye and a pigment.

The colorant included in the color filter layer CF_5may vary depending on the light emitted from the light-emitting element300. For example, when the light-emitting element300emits red light, the color filter layer CF_5may include a red colorant. Likewise, when the light-emitting element300emits green or blue light, the color filter layer CF_5may include a green or blue colorant.

The light emitted from the light-emitting element300may be reflected from inclined surfaces of each of banks210,220, and230, directed to upper portions of the banks210,220, and230, and incident on the color filter layer CF_5. The color filter layer CF_5may block light of different colors except for any first color from being transmitted, and each pixel PX may emit only light of any color according to the colorant of the color filter layer CF_5. The color filter layer CF_5may improve the color purity of the light emitted from the light-emitting element300.

In some embodiments, the display device10_5includes an emission area EMA and a non-emission area NEA, and the light-emitting element300and circuit elements are disposed in different areas. Accordingly, in the display device10_5, the light emitted from the light-emitting element300may also be emitted in a downward direction rather than an upward direction with respect to a substrate110.

Referring toFIG.25, a display device10_6according to some example embodiments includes a transparent organic film OF_6disposed on a second insulating layer520and overlapping a light-emitting element300in a thickness direction, and an one electrode123_6of a driving transistor DT may be disposed to cover the transparent organic film OF_6. The one electrode123_6may include a material having a high reflectance to reflect light emitted from the light-emitting element300and transmitted through the transparent organic film OF_6toward a substrate110_6. Accordingly, the display device10_6may have a bottom emission structure in which light is emitted toward a bottom surface of the substrate110_6on which the light-emitting element300is disposed.

In some embodiments, the display device10_6may further include an opposite substrate115_6spaced from and opposite to the substrate110_6, and a color filter layer CF_6may be disposed on one surface of the opposite substrate115_6. The light emitted from the light-emitting element300may be reflected by the one electrode123_6through the transparent organic film OF_6and travel to the bottom surface of the substrate110_6to be incident on the color filter layer CF_6. Only a portion of the light incident on the color filter layer CF_6may be transmitted, and another portion of the light incident on the color filter layer CF_6may be blocked from being transmitted and may be emitted to the other surface of the opposite substrate115_6.

Further, in some example embodiments, the transparent organic film OF_6may be omitted, and a color filter layer CF may be disposed between the light-emitting element300and the one electrode123.

Referring toFIG.26, in a display device10_7according to some example embodiments, a color filter layer CF_7may be disposed on a second insulating layer520to overlap a light-emitting element300, and an one electrode123_7of a driving transistor DT may be disposed to cover the color filter layer CF_7. The example embodiment ofFIG.26differs from the example embodiment described with reference toFIG.25in that the color filter layer CF_7is disposed in an area in which the transparent organic film OF_6is disposed and the opposite substrate115_6is omitted. Descriptions of other configurations, except for the above description, are the same as described above, and thus detailed descriptions of other configurations will be omitted.

The display device10_7may further include a reflective layer that reflects light so that the light emitted from the light-emitting element300is concentrated within a predetermined (or set) area.

Referring toFIG.27, a display device10_8according to some example embodiments may further include a reflective layer127_8disposed on a second insulating layer520to overlap a second electrode250. The reflective layer127_8includes a material having a high reflectance and is disposed above the second electrode250. Some of light emitted from a light-emitting element300may travel toward the reflective layer127_8and may be reflected by the reflective layer127_8to travel in an upward direction with respect to a substrate110. The example embodiment ofFIG.27differs from the example embodiment described with reference toFIG.4in that the reflective layer127_8is further included. Other repeated descriptions will be omitted, as one of the ordinary skill in the art would be able to appreciate from the detailed description of the previous drawings.

In a display device according to some example embodiments, each pixel includes an emission area in which light-emitting elements are disposed and a non-emission area in which circuit elements are disposed so that the display device can have a top emission structure or a bottom emission structure with respect to a substrate.

Further, an active material layer of a transistor among the circuit elements can be disposed above the light-emitting elements. Contact electrodes in contact with the light-emitting elements and electrodes can be disposed on the same layer as the active material layer of the transistor and can be formed in the same process together with the active material layer during the fabricating process of the display device. Accordingly, in the display device according to some example embodiments, the number of fabricating processes can be reduced.