KR20230027132A - Light emitting device and display device using the same - Google Patents

Abstract

A light emitting device with increased luminous efficiency and a display device including the same according to an embodiment of the present invention are provided. A light emitting device including an n-type semiconductor layer and a p-type semiconductor layer includes an n-type electrode connected to the n-type semiconductor layer and a p-type electrode connected to the p-type semiconductor layer. The surface corresponding to the planar p-type semiconductor layer is formed in a long trapezoidal shape to increase luminous efficiency.

Description

Light emitting device and display device using the same {LIGHT EMITTING DEVICE AND DISPLAY DEVICE USING THE SAME}

The present invention relates to a light emitting element and a display device using the same, and more particularly, to a light emitting element capable of increasing product reliability by increasing electrode connection efficiency and wire connection stability with respect to an electrical connection relationship between a light emitting element and a wiring electrode, and a display using the same to provide the device.

Display devices are widely used as display screens of notebook computers, tablet computers, smart phones, portable display devices, and portable information devices, in addition to display devices of televisions or monitors.

The display device can be divided into a reflective display device and a light emission type display device. A reflective display device is a type of display device in which natural light or light emitted from external lighting of the display device is reflected on the display device to display information, and is a light emitting type display device. The display device is a method in which a light emitting element or light source is embedded in the display device and information is displayed using light generated from the built-in light emitting element or light source.

The built-in light emitting element may use a light emitting element capable of emitting various wavelengths of light or may use a light emitting element emitting white or blue light and a color filter capable of changing the wavelength of light emitting light.

In this way, in order to implement an image as a display device, a plurality of light emitting elements are disposed on a substrate of the display device, and a driving element that supplies a driving signal or a driving current to control each light emitting element to individually emit light is a light emitting element. Arranged on the substrate together with, interprets the arrangement of information to display a plurality of light emitting elements disposed on the substrate and displays them on the substrate.

In other words, in such a display device, a plurality of pixels are disposed, each pixel uses a thin film transistor as a driving element, a switching element, and is connected to the thin film transistor to drive the display device. The image is displayed by the operation of

Representative display devices using thin film transistors include liquid crystal displays and organic light emitting display devices. Among them, since the liquid crystal display device is not self-luminous, a backlight unit disposed to emit light is required on the lower (rear side) of the liquid crystal display device. Due to the additional backlight unit, the thickness of the liquid crystal display device is increased, there are limitations in implementing the display device in various shapes such as flexible or circular designs, and luminance and response speed may be reduced.

On the other hand, a display device with a self-light emitting element can be implemented thinner than a display device with a built-in light source, and has the advantage of implementing a flexible and foldable display device.

A display device having such a self-luminous element may include an organic light emitting display device including an organic material as a light emitting layer and a micro LED display device using a micro LED element as a light emitting element. Since the self-display device does not require a separate light source, it can be used as a display device that is thinner or has various shapes.

However, since an organic light emitting display device using an organic material does not require a separate light source, defective pixels are easily generated due to moisture and oxygen, and therefore, various technical ideas for minimizing penetration of oxygen and moisture are additionally required.

In relation to the above problems, recently, research and development of a display device using a micro light emitting diode as a light emitting device has been conducted, and such a light emitting display device has high image quality and high reliability. Therefore, it is in the limelight as a next-generation display device.

An LED device is a semiconductor light emitting device using the property of emitting light when a current flows through a semiconductor, and is widely used in lighting, TV, and various display devices. An LED device is composed of an n-type semiconductor layer, a p-type semiconductor layer, and an active layer between them. When current flows, electrons are formed in the n-type semiconductor layer and holes are formed in the p-type semiconductor layer, which combine in the active layer to emit light.

The LED device is composed of a compound semiconductor such as GaN, so that a high current can be injected due to the characteristics of an inorganic material, so that high brightness can be implemented, and environmental effects such as heat, moisture, and oxygen are low, and it has high reliability.

In addition, since the LED device has an internal quantum efficiency of 90%, which is higher than that of the organic light emitting display device, there is an advantage in implementing a display device capable of displaying a high-brightness image and consuming low power.

In addition, unlike an organic light emitting display device, an encapsulation film or encapsulation substrate is not required to minimize the permeation of oxygen and moisture to a level where the influence of oxygen and moisture is insignificant due to the use of inorganic materials. There is an advantage in minimizing the non-display area of the display device, which is a margin area that may occur due to the arrangement.

However, a light emitting device such as an LED device may require a procedure to be formed using a separate semiconductor substrate and then transplanted to a display device, and a method of forming a light emitting device using a separate semiconductor substrate must be used. However, there is a problem in that manufacturing cost increases.

However, in order to provide a display device having the above advantages, a technology for arranging the light emitting element in the right position on the display device and a technology for minimizing manufacturing cost while minimizing errors that may occur during the arrangement process are required. need. In recent years, many research activities have been conducted on this.

As described above, there are several technical requirements to implement a light emitting display device using an LED element as a light emitting element of a unit pixel. First, an LED element is crystallized on a semiconductor wafer substrate such as sapphire or silicon (Si), and a plurality of crystallized LED chips are moved to a substrate with a driving element, but in a position corresponding to each pixel An elaborate transfer process for locating the LED element is required.

Although the LED device can be formed using an inorganic material, it needs to be formed by crystallization. In order to crystallize an inorganic material such as GaN, the inorganic material must be crystallized on a substrate capable of inducing crystallization. A substrate capable of efficiently inducing crystallization of the inorganic material is a semiconductor substrate, and as described above, the inorganic material must be crystallized on the semiconductor substrate.

A process of crystallizing an LED device is also referred to as epitaxy, epitaxial growth, or an epi process. The epitaxial process means growing by taking a specific orientation relationship on the surface of a certain crystal. In order to form the device structure of an LED device, GaN-based compound semiconductors must be stacked in the form of a pn junction diode on a substrate. It grows by inheriting the crystallinity of the layer of

At this time, since the defect inside the crystal acts as a nonradiative center in the electron-hole recombination process, the crystallinity of the crystals forming each layer in the LED device using photons This has a decisive effect on device efficiency.

Currently, the above-mentioned sapphire substrate is mainly used as the substrate mainly used, and recently, research activities for substrates based on GaN have been actively conducted.

In this way, due to the high price of the semiconductor substrate required for crystallizing the inorganic material such as GaN constituting the LED light emitting element on the semiconductor substrate, a large amount of light emitting pixels of a display device rather than an LED as a light source used for simple lighting or backlighting When LEDs are used, there is a problem in that manufacturing costs increase.

In addition, as described above, a step of transferring the LED element formed on the semiconductor substrate to the substrate constituting the display device is required. In this process, it is difficult to separate the LED element formed on the semiconductor substrate. There are many difficulties and problems even when correctly transplanting the LED device to a desired location.

In transferring an LED element formed on a semiconductor substrate to a substrate realizing a display device, a method of using a transfer substrate using a polymer material such as PDMS, a transfer method using electromagnetic or static electricity, or physically picking up and moving one element at a time A variety of transcription methods can be used, and research activities on various transcription methods are being conducted.

Such a transfer process is related to the productivity of the process of implementing a display device, and it can be said that the method of transferring LED elements one by one is inefficient for mass production.

Therefore, a plurality of LED elements are separated from the semiconductor substrate using a transfer substrate using a polymer material to accurately position the plurality of LED elements on the substrate constituting the display device, especially the driving element disposed on the thin film transistor and the pad electrode connected to the power electrode. A transfer process or construction method is required.

During the above-described transfer process or during the subsequent process following the transfer process, defects such as the LED element being overturned and transferred may occur in the process of moving or transferring the LED element according to conditions of vibration or heat, and finding such a defect There were many difficulties in recovering.

Taking a general transfer process as an example, the transfer process of an LED device will be described as an example. An LED element is formed on a semiconductor substrate and an electrode is formed on the semiconductor layer to complete the individual LED element. Thereafter, the semiconductor substrate and the PDMS substrate (hereinafter referred to as a transfer substrate) are brought into contact to move the LED element to the transfer substrate. Since the transfer substrate should transfer the LED element from the semiconductor substrate to the transfer substrate considering the distance of the pixel pitch of the LED element formed on the semiconductor substrate, the transfer substrate is used to receive the LED element considering the pixel pitch of the display device. Protrusions and the like protrude and are disposed.

The LED element is separated from the semiconductor substrate by irradiating the laser with the LED element through the rear surface of the semiconductor substrate. At this time, when the LED element is separated from the semiconductor substrate in the process of irradiating the laser, the GaN material of the semiconductor substrate is exposed to the high energy of the laser. Due to the concentration of energy, a rapid physical expansion may occur, which may result in a shock. (This is called primary warrior.)

Thereafter, the LED element transferred to the transfer substrate is transferred onto the substrate constituting the display device. A protective layer for insulating/protecting the thin film transistor is disposed on the substrate having the thin film transistor, and then an adhesive layer is disposed on the protective layer. .

When pressure is applied by bringing the transfer substrate into contact with the substrate of the display device, the LED element transferred to the transfer substrate is transferred to the substrate side of the display device by the adhesive layer on the protective layer described above.

At this time, the adhesive force between the transfer substrate and the LED element is smaller than the adhesive force between the substrate constituting the display device and the LED element so that the LED element on the transfer substrate is smoothly transferred to the substrate of the display device. (This is called secondary transcription)

A semiconductor substrate and a substrate constituting a display device are basically different in size, and a substrate constituting a display device is usually large. Due to the difference in area and size, if the above-described first and second transfer are repeatedly performed for each area of the substrate of the display device, it is possible to transfer the LED element corresponding to each pixel constituting the display device. .

In the process of repeating the primary transfer and the secondary transfer, the LED element may be transferred to an unintended position, and various errors may occur depending on the number of transfers or the process deviation of the transfer process.

The LED element formed on the semiconductor substrate may be a red, blue, or green LED element according to its type, or may be a white LED element. In a method of implementing pixels of a display device by using LED elements emitting light of different wavelengths, the number of primary and secondary transfers described above may be further increased.

Even if the light emitting element is transferred to the substrate through a precise transfer process due to the increased number of primary and secondary transfers, if a defect occurs, all the first and secondary transferred light emitting elements due to the defect are discarded or an error Expenses are incurred in the process of finding and correcting devices that have occurred.

An object to be solved in accordance with an embodiment of the present invention is to provide a light emitting element having further increased light efficiency and a display device using the light emitting element when the light emitting element is formed on a semiconductor substrate.

Another problem to be solved according to another embodiment of the present invention is a light emitting device having a reduced manufacturing cost by using a light emitting device capable of forming a greater number of light emitting devices on a semiconductor substrate of the same area in forming a light emitting device on a semiconductor substrate. and a display device using the same.

Solved problems according to an embodiment of the present invention are not limited to the above-mentioned problems, and other problems not mentioned above will be clearly understood by those skilled in the art from the following description.

A light emitting device with increased luminous efficiency and a display device using the same are provided according to an embodiment of the present invention. The light emitting element includes an n-type semiconductor and a p-type semiconductor, an n-type electrode is disposed on the n-type semiconductor, and a p-type electrode is disposed on the p-type semiconductor. Since the planar light emitting device has a trapezoidal shape to increase the light emitting area of the p-type semiconductor layer having the p-type electrode, it is possible to provide a light emitting device with increased luminous efficiency and a display device using the same.

According to an embodiment of the present invention, by using a light emitting device having a structure capable of increasing the luminous efficiency of the light emitting device, there is an effect of improving the luminous efficiency of the display device. In addition, there is an effect of minimizing power consumption of the display device by using the light emitting element. On the other hand, there is an effect of minimizing manufacturing cost by increasing the number of light emitting devices that can be taken from a semiconductor device.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

Since the content of the invention described in the problem to be solved, the means for solving the problem, and the effect above does not specify the essential features of the claim, the scope of the claim is not limited by the matters described in the content of the invention.

1 is a schematic plan view of a light emitting display device according to an exemplary embodiment of the present invention.
FIG. 2 is a schematic circuit diagram for explaining a configuration of a unit pixel according to an exemplary embodiment shown in FIG. 1 .
Figure 3 is a schematic cross-sectional view for explaining the arrangement of light emitting devices according to an embodiment of the present invention.
4A and 4B are schematic plan views for explaining a light emitting device according to an embodiment of the present invention.
5 is a schematic diagram of a semiconductor substrate used to form a light emitting device according to an embodiment of the present invention.
FIG. 6 is a partially enlarged view of area A according to FIG. 5 .
7A to 7C are schematic plan views for explaining a light emitting device having increased luminous efficiency compared to a conventional light emitting device.
8A and 8B are schematic plan views illustrating a light emitting element having a similar light emitting efficiency and having an increased number of chamfers.
9A and 9B are schematic diagrams for explaining a process of transferring a light emitting element.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, only these embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative, so the present invention is not limited to the details shown. Like reference numbers designate like elements throughout the specification. In addition, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. When 'includes', 'has', 'consists of', etc. mentioned in this specification is used, other parts may be added unless 'only' is used. In the case where a component is expressed in the singular, the case including the plural is included unless otherwise explicitly stated.

In interpreting the components, even if there is no separate explicit description, it is interpreted as including the error range.

In the case of a description of a positional relationship, for example, 'on top of', 'on top of', 'at the bottom of', 'next to', etc. Or, unless 'directly' is used, one or more other parts may be located between the two parts.

In the case of a description of a temporal relationship, for example, when a temporal precedence relationship is described as 'after', 'continue to', 'after ~', 'before', etc., 'immediately' or 'directly' As long as ' is not used, non-continuous cases may also be included.

In the case of description of the flow relationship of a signal, for example, even in the case of 'a signal is passed from node A to node B', unless 'direct' or 'direct' is used, from node A via another node This may include a case where a signal is transmitted to node B.

Although first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, the first component mentioned below may also be the second component within the technical spirit of the present invention.

Each feature of the various embodiments of the present invention can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each embodiment can be implemented independently of each other or can be implemented together in a related relationship. may be

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

1 is a schematic plan view of a light emitting display device according to an exemplary embodiment of the present invention, and FIG. 2 is a schematic circuit diagram for explaining a configuration of a unit pixel according to an exemplary embodiment shown in FIG. 1 . Referring to FIGS. 1 and 2 , the light emitting display device 100 according to an exemplary embodiment of the present invention includes a display area AA having a plurality of unit pixels UP and a non-display area IA defined. A substrate 110 is included.

The unit pixel UP may be composed of a plurality of sub-pixels SP1, SP2, and SP3 on the front surface 110a of the substrate 110, and is typically composed of red, blue, and green. It may include, but is not limited to, subpixels SP1 , SP2 , and SP3 emitting light, and may include subpixels emitting light such as white.

The substrate 110 is a thin film transistor array substrate, and may be made of glass or plastic material, and may be a substrate divided into two or more layers or a bonding of two or more substrates. The non-display area IA may be defined as an area on the substrate 110 excluding the display area AA, may have a relatively narrow width, and may be defined as a bezel area.

Each of the plurality of unit pixels UP is disposed in the display area AA. At this time, each of the plurality of unit pixels UP is disposed in the display area AA to have a preset first reference pixel pitch along the X-axis direction and a preset second reference pixel pitch along the Y-axis direction. Since the first reference pixel pitch may be defined as a distance between the respective central portions of adjacent unit pixels UP, the second reference pixel pitch may be similar to the first reference pixel pitch, and may be defined as a distance between adjacent unit pixels UP in the reference direction. It can be defined as the distance between the midpoints.

Meanwhile, the distance between the subpixels SP1, SP2, and SP3 constituting the unit pixel UP is also defined as a first reference subpixel pitch and a second reference subpixel pitch similar to the first reference pixel pitch and the second reference pixel pitch. It can be.

In the light emitting display device 100 including the LED element 150 which is an LED element, the width of the non-display area IA may be smaller than the aforementioned pixel pitch or subpixel pitch, and may be equal to or smaller than the pixel pitch or subpixel pitch. When a multi-screen display device is configured with the light emitting display device 100 having a non-display area IA of length, the non-display area IA is smaller than the pixel pitch or sub-pixel pitch, so the multi-screen substantially free of bezel areas. A display device can be implemented.

As described above, in order to realize a multi-screen display device with substantially no or minimized bezel area, the light emitting display device 100 has a first reference pixel pitch, a second reference pixel pitch, The first reference subpixel pitch and the second reference subpixel pitch may be kept constant, but the display area AA is defined as a plurality of zones, and the above-described pitch lengths are made different from each other in each zone, but the non-display area ( By making the pixel pitch of the area adjacent to IA) wider than that of other areas, the size of the bezel area can be made relatively smaller than the pixel pitch.

In this way, since the light emitting display device 100 having different pixel pitches may cause image distortion, image processing is performed by sampling image data by comparing the set pixel pitch with an adjacent area, and The bezel area can be minimized while minimizing distortion.

However, in order to minimize the non-display area (IA), a pad area for connection with a circuit unit capable of transmitting and receiving power and data signals to the unit pixel (UP) in which the LED element 150 is located and a drive IC for driving are provided. A minimum area is required for

Referring to FIG. 2 , the configuration and circuit structure of the sub-pixels SP1 , SP2 , and SP3 constituting the unit pixel UP of the light emitting display device 100 will be described. The pixel driving lines are provided on the front surface 110a of the substrate 110 to supply necessary signals to each of the plurality of subpixels SP1 , SP2 , and SP3 . Pixel driving lines according to an exemplary embodiment include a plurality of gate lines GL, a plurality of data lines DL, a plurality of driving power lines DPL, and a plurality of common power lines CPL.

Each of the plurality of gate lines GL is provided on the front surface 110a of the substrate 110, and extends along the first horizontal axis direction X of the substrate 110 while extending in the second horizontal axis direction. They are spaced at regular intervals along (Y).

The plurality of data lines DL are provided on the front surface 110a of the substrate 110 to intersect the plurality of gate lines GL, and travel in the second horizontal axis direction Y of the substrate 110. While extending long along the first horizontal axis direction (X) are spaced apart at regular intervals.

The plurality of driving power lines DPL are provided on the substrate 110 in parallel with each of the plurality of data lines DL, and may be formed together with each of the plurality of data lines DL. Each of the plurality of driving power lines DPL supplies pixel driving power provided from the outside to adjacent subpixels SP.

The plurality of common power lines CPL are provided on the substrate 110 in parallel with each of the plurality of gate lines GL, and may be formed together with each of the plurality of gate lines GL. Each of the plurality of common power lines CPL supplies common power supplied from the outside to adjacent subpixels SP1 , SP2 , and SP3 .

Each of the plurality of subpixels SP1 , SP2 , and SP3 is provided in a subpixel area defined by the gate line GL and the data line DL. Each of the plurality of sub-pixels SP1 , SP2 , and SP3 may be defined as a minimum unit area in which light is actually emitted.

At least three sub-pixels SP1 , SP2 , and SP3 adjacent to each other may constitute one unit pixel UP for color display. For example, one unit pixel UP includes a red sub-pixel SP1, a green sub-pixel SP2, and a blue sub-pixel SP3 adjacent to each other along a first horizontal axis direction X, and improves luminance. For this, a white sub-pixel may be further included.

Optionally, one of the plurality of driving power lines DPL may be provided for each of the plurality of unit pixels UP. In this case, at least three sub-pixels SP1 , SP2 , and SP3 constituting each unit pixel UP share one driving power line DPL. Accordingly, the number of driving power lines for driving each sub-pixel SP1 , SP2 , and SP3 may be reduced, and the aperture ratio of each unit pixel UP may be increased by the number of driving power lines that decreases or The size of the pixel UP may be reduced.

Each of the plurality of sub-pixels SP1 , SP2 , and SP3 according to an embodiment of the present invention includes a pixel circuit PC and an LED device 150 .

The pixel circuit PC is provided in a circuit area defined in each sub-pixel SP and is connected to adjacent gate lines GL, data lines DL, and driving power line DPL. The pixel circuit (PC) is based on the pixel driving power supplied from the driving power line (DPL), the LED element 150 according to the data signal from the data line (DL) in response to the scan pulse from the gate line (GL). ) to control the current flowing through it. A pixel circuit PC according to an exemplary embodiment includes a switching thin film transistor T1, a driving thin film transistor T2, and a capacitor Cst.

The switching thin film transistor T1 includes a gate electrode connected to the gate line GL, a first electrode connected to the data line DL, and a second electrode connected to the gate electrode N1 of the driving thin film transistor T2. Here, the first and second electrodes of the switching thin film transistor T1 may be a source electrode or a drain electrode according to the direction of the current. The switching thin film transistor T1 is switched according to the scan pulse supplied to the gate line GL and supplies the data signal supplied to the data line DL to the driving thin film transistor T2.

The driving thin film transistor T2 is turned on by the voltage supplied from the switching thin film transistor T1 and/or the voltage of the capacitor Cst, thereby controlling the amount of current flowing from the driving power supply line DPL to the LED element 150. do. To this end, the driving thin film transistor T2 according to an embodiment of the present invention includes a gate electrode connected to the second electrode N1 of the switching thin film transistor T1, a drain electrode connected to the driving power supply line DPL, and an LED. It includes a source electrode connected to element 150 . The driving thin film transistor T2 controls the light emission of the LED element 150 by controlling the data current flowing from the driving power line DPL to the LED element 150 based on the data signal supplied from the switching thin film transistor T1. do.

The capacitor Cst is provided in an overlapping region between the gate electrode N1 and the source electrode of the driving thin film transistor T2 to store a voltage corresponding to the data signal supplied to the gate electrode of the driving thin film transistor T2, and store the stored voltage. to turn on the driving thin film transistor T2.

Optionally, the pixel circuit PC may further include at least one compensation thin film transistor for compensating for a change in the threshold voltage of the driving thin film transistor T2 and further include at least one auxiliary capacitor. The pixel circuit PC may additionally receive compensation power such as an initialization voltage according to the number of thin film transistors and auxiliary capacitors. Therefore, since the pixel circuit PC according to an embodiment of the present invention drives the LED element 150 through a current driving method in the same way as each sub-pixel of the organic light emitting display device, the known pixel pixel of the organic light emitting display device circuit can be changed.

The LED device 150 is mounted on each of the plurality of sub-pixels SP1, SP2, and SP3. The LED device 150 is electrically connected to the pixel pixel circuit PC of the corresponding sub-pixel SP and the common power line CPL, so that the pixel pixel circuit PC, that is, the driving thin film transistor T2 is connected to the common power line. Light is emitted by the current flowing through (CPL). The LED device 150 according to an embodiment of the present invention may be a light device or a light emitting diode chip that emits any one of red light, green light, blue light, and white light. Here, the light emitting diode chip may have a scale of 1 to 100 micrometers, but may have a size smaller than the size of the rest of the light emitting area excluding the circuit area occupied by the pixel pixel circuit (PC) among the subpixel areas, which is not limited thereto. .

Figure 3 is a schematic cross-sectional view for explaining the arrangement of light emitting devices according to an embodiment of the present invention. Hereinafter, it will be described with reference to FIG. 3, but will be described in conjunction with the previous drawings.

Each sub-pixel (SP1, SP2, SP3) of the display device according to an embodiment of the present invention includes a protective layer 113, an LED device 150, planarization layers 115-1 and 115-2, a pixel electrode PE, and a common electrode CE.

First, although the thickness of the substrate 110 is shown as relatively thin in FIG. 3, the thickness of the substrate 110 may be substantially thicker than the total thickness of the layer structure provided on the substrate 110, It may be a substrate composed of a plurality of layers or a plurality of substrates bonded together.

The pixel pixel circuit (PC) includes a switching thin film transistor (T1), a driving thin film transistor (T2), and a capacitor (C). Since the pixel circuit PC is the same as described above, a detailed description thereof will be omitted, and the structure of the driving thin film transistor T2 will be described below as an example.

The driving thin film transistor T2 includes a gate electrode GE, a semiconductor layer SCL, a source electrode SE, and a drain electrode DE.

The gate electrode GE is disposed on the substrate 110 along with the gate line GL. The gate electrode GE is covered by the gate insulating layer 112 . The gate insulating layer 112 may be formed of a single layer or a plurality of layers made of an inorganic material, and may be formed of silicon oxide (SiOx), silicon nitride (SiNx), or the like.

The semiconductor layer SCL is provided in a preset pattern (or island) shape on the gate insulating layer 112 to overlap the gate electrode GE. The semiconductor layer SCL may be formed of a semiconductor material made of any one of amorphous silicon, polycrystalline silicon, oxide, and organic material, but is not limited thereto.

The source electrode SE is disposed to overlap one side of the semiconductor layer SCL. The source electrode SE is disposed together with the data line DL and the driving power line DPL.

The drain electrode DE overlaps the other side of the semiconductor layer SCL and is spaced apart from the source electrode SE. The drain electrode DE is disposed together with the source electrode SE, and branches or protrudes from an adjacent driving power supply line DPL.

Additionally, the switching thin film transistor T1 constituting the pixel pixel circuit PC is disposed in the same structure as the driving thin film transistor T2. At this time, the gate electrode of the switching thin film transistor T1 branches or protrudes from the gate line GL, the first electrode of the switching thin film transistor T1 branches or protrudes from the data line DL, and the switching thin film transistor T1 The second electrode of ) is connected to the gate electrode GE of the driving thin film transistor T2 through a via hole provided in the gate insulating layer 112 .

The protective layer 113 is provided on the entire surface of the substrate 110 to cover the sub-pixel SP, that is, the pixel circuit PC. The protective layer 113 provides a flat surface while protecting the pixel circuit PC. The protective layer 113 according to an embodiment of the present invention may be made of an organic material such as benzocyclobutene or photo acryl, but is preferably made of a photo acryl material for convenience in processing.

The LED device 150 according to an embodiment of the present invention may be disposed on the protective layer 113 using an adhesive member 114 . Alternatively, it may be disposed in a concave portion provided on the protective layer 113, and the inclined surface due to the concave portion in the protective layer 113 advances the light emitted from the LED element 150 in a specific direction to improve luminous efficiency. can play a role in

The LED element 150 is electrically connected to the pixel pixel circuit (PC) and the common power line (CPL) so that the current flowing from the pixel pixel circuit (PC), that is, the driving thin film transistor (T2) to the common power line (CPL) glow The LED device 150 according to an embodiment of the present invention includes a light emitting layer (EL), a first electrode (or anode terminal) (E1), and a second electrode (or cathode terminal) (E2).

The LED element 150 emits light according to recombination of electrons and holes according to the current flowing between the first electrode E1 and the second electrode E2.

The planarization layers 115 - 1 and 115 - 2 are disposed on the protective layer 113 to cover the LED device 150 . That is, the planarization layers 115-1 and 115-2 have a thickness sufficient to cover the entire surface of the protective layer 113, where the LED element 150 is disposed, and the rest of the entire surface of the protective layer 113. ) is placed on

The planarization layers 115-1 and 115-2 may be formed of one layer, and as shown, a planarization layer having a multi-layer structure composed of a first planarization layer 115-1 and a second planarization layer 115-2 ( 115-1, 115-2).

As such, the planarization layers 115 - 1 and 115 - 2 provide a flat surface on the protective layer 113 . In addition, the planarization layers 115-1 and 115-2 serve to fix the position of the LED element 150.

The pixel electrode PE connects the first electrode E1 of the LED element 150 to the drain electrode DE of the driving thin film transistor T2, and is connected to the source electrode SE according to the configuration of the thin film transistor T2. Connection configurations are also possible. Such a pixel electrode PE may be defined as an anode electrode. The pixel electrode PE according to an embodiment of the present invention is provided on the entire surface of the planarization layers 115-1 and 115-2 overlapping the first electrode E1 of the LED device 150 and the driving thin film transistor T2. . The pixel electrode PE is the drain electrode DE or source electrode of the driving thin film transistor T2 through the first circuit contact hole CCH1 provided through the passivation layer 113 and the planarization layers 115-1 and 115-2. SE, and electrically connected to the first electrode E1 of the LED element 150 through the electrode contact hole ECH provided in the planarization layers 115-1 and 115-2. Accordingly, the first electrode E1 of the LED device 150 is electrically connected to the drain electrode DE or the source electrode SE of the driving thin film transistor T2 through the pixel electrode PE.

Regarding the connection relationship between the source electrode SE and the drain electrode DE, it is shown that the drain electrode DE is connected to the pixel electrode PE, but a configuration in which the pixel electrode PE and the source electrode SE are connected is also possible. And this can be said to be the choice of those skilled in the art.

The pixel electrode PE may be made of a transparent conductive material when the display device is a top emission type, and may be made of a light reflective conductive material when the display device is a bottom emission type. Here, the transparent conductive material may be indium tin oxide (ITO) or indium zinc oxide (IZO), but is not limited thereto. The light reflecting conductive material may be Al, Ag, Au, Pt, or Cu, but is not limited thereto. The pixel electrode PE made of the light reflective conductive material may be formed of a single layer including the light reflective conductive material or a multi-layer stack of the single layers.

The common electrode CE electrically connects the second electrode E2 of the LED device 150 and the common power supply line CPL, and may be defined as a cathode electrode. The common electrode CE is provided on the entire surface of the planarization layers 115-1 and 115-2 overlapping the common power line CPL while overlapping the second electrode E2 of the LED device 150. Here, the common electrode CE may be made of the same material as the pixel electrode PE.

One side of the common electrode CE according to an embodiment of the present invention passes through the gate insulating layer 112, the protective layer 113, and the planarization layers 115-1 and 115-2 overlapping the common power line CPL. It is electrically connected to the common power line CPL through the provided second circuit contact hole CCH2. The other side of the common electrode CE according to an embodiment of the present invention is through the electrode contact hole ECH provided in the planarization layers 115-1 and 115-2 so as to overlap the second electrode E2 of the LED device 150. It is electrically connected to the second electrode E2 of the LED element 150. Accordingly, the second electrode E2 of the LED device 150 is electrically connected to the common power line CPL through the common electrode CE.

According to an embodiment of the present invention, the pixel electrode PE and the common electrode CE include the planarization layers 115-1 and 115 including the first and second circuit contact holes CCH1 and CCH2 and the electrode contact hole ECH. -2) It can be provided simultaneously by a deposition process of depositing an electrode material on the electrode, a photolithography process, and an electrode patterning process using an etching process. Accordingly, in one embodiment of the present invention, since the pixel electrode PE and the common electrode CE connecting the LED element 150 to the pixel circuit PC can be disposed at the same time, the electrode connection process can be simplified. , The process time for connecting the LED element 150 and the pixel circuit (PC) can be greatly reduced, and through this, the productivity of the display device can be improved.

According to one embodiment of the present invention, the display device further includes a transparent buffer layer 116 .

The transparent buffer layer 116 is provided on the substrate 110 so as to cover the entirety of the planarization layers 115-1 and 115-2 on which the pixel electrode PE and the common electrode CE are formed, thereby forming the planarization layers 115-1 and 115-2. ) to protect the LED element 150 and the pixel pixel circuit (PC) from external impact while providing a flat surface. Accordingly, each of the pixel electrode PE and the common electrode CE is provided between the planarization layers 115 - 1 and 115 - 2 and the transparent buffer layer 116 . The transparent buffer layer 116 according to an embodiment of the present invention may be an optical clear adhesive (OCA) or an optical clear resin (OCR), but is not limited thereto.

The display device according to an exemplary embodiment of the present invention further includes a reflective layer 111 provided under the emission area of each sub-pixel SP.

The reflective layer 111 is provided on the substrate 110 to overlap the light emitting region including the LED element 150 . The reflective layer 111 according to an embodiment of the present invention may be made of the same material as the gate electrode GE of the driving thin film transistor T2 and may be provided on the same layer as the gate electrode GE, but is not limited thereto. The reflective layer 111 may be made of the same material as any one of the electrodes constituting the driving thin film transistor T2.

The reflective layer 111 reflects light incident from the LED element 150 to the top of the LED element 150 . Accordingly, the display device according to an exemplary embodiment includes the reflective layer 111 and has a top emission structure. However, when the display device according to an exemplary embodiment of the present invention has a bottom emission structure, the reflective layer 111 may be omitted or disposed above the LED element 150 .

Optionally, the reflective layer 111 may be made of the same material as the source/drain electrodes SE/DE of the driving thin film transistor T2 and may be provided on the same layer as the source/drain electrodes SE/DE.

In the display device according to an exemplary embodiment of the present invention, the LED element 150 mounted on each sub-pixel SP may be disposed at a position corresponding to the upper portion of the corresponding reflective layer 111 by the adhesive member 114 .

The adhesive member 114 primarily fixes the LED element 150 of each sub-pixel SP. The adhesive member 114 according to an embodiment of the present invention is in contact with the lower part of the LED element 150 and is used to minimize dislocation of the position during the mounting process of the LED element 150 and to be implanted at the same time as an intermediate substrate. It is possible to minimize the implantation process defect of the LED element 150 by allowing the LED element 150 to fall smoothly from the above.

The adhesive member 114 according to an embodiment of the present invention is dotted on each sub-pixel (SP) and spreads by a pressing force applied during the mounting process of the light emitting device, thereby adhering to the lower portion of the LED device 150. there is. Accordingly, the position of the LED element 150 may be primarily fixed by the adhesive member 114 . Therefore, according to the present embodiment, the mounting process of the light emitting element is performed by simply bonding the LED element 150 to the surface, so that the mounting process time of the light emitting element can be greatly reduced.

In addition, the adhesive member 114 is interposed between the protective layer 113 and the planarization layers 115-1 and 115-2, and is interposed between the LED element 150 and the protective layer 113. The adhesive member 114 according to this other example is coated with a constant thickness on the entire surface of the protective layer 113, but a portion of the adhesive member 114 coated on the entire surface of the protective layer 113 in which contact holes are to be provided is a contact Removed upon placement of holes. Accordingly, in one embodiment of the present invention, the process time for arranging the adhesive member 114 is shortened by coating the entire surface of the protective layer 113 with a uniform thickness with the adhesive member 114 immediately before the mounting process of the light emitting device. can make it

In one embodiment of the present invention, since the adhesive member 114 is provided on the entire surface of the protective layer 113, the planarization layers 115-1 and 115-2 of this example are provided to cover the adhesive member 114.

In another embodiment of the present invention, there is a concave portion for accommodating the LED element 150 separately, and the adhesive member 114 may be positioned inside the concave portion. However, the concave portion for accommodating the above-described LED element 150 may be deleted according to various process conditions for implementing the display device.

A mounting process of a light emitting device according to an embodiment of the present invention includes a process of mounting a red light emitting device on each of the red subpixels SP1, a process of mounting a green light emitting device on each of the green subpixels SP2, and a process of mounting a blue light emitting element on each of the blue sub-pixels SP3, and a process of mounting a white light emitting element on each of the white sub-pixels.

A mounting process of a light emitting device according to an embodiment of the present invention may include only a process of mounting a white light emitting device on each of the subpixels. In this case, the substrate 110 includes a color filter layer overlapping each sub-pixel. The color filter layer transmits only white light having a wavelength of a color corresponding to a corresponding subpixel.

A process of mounting a light emitting device according to an embodiment of the present invention may include only a process of mounting a light emitting device of a first color in each of the subpixels. In this case, the substrate 110 includes a wavelength conversion layer and a color filter layer overlapping each sub-pixel. The wavelength conversion layer emits light of a second color based on some of the light of the first color incident from the light emitting device. The color filter layer transmits only light having a wavelength of a color corresponding to a corresponding sub-pixel among white light resulting from mixing light of a first color and light of a second color. Here, the first color may be blue, and the second color may be yellow. Also, the wavelength conversion layer may include phosphors or quantum dot particles that emit light of a second color based on some of the light of the first color.

4A and 4B are schematic plan views for explaining a light emitting device according to an embodiment of the present invention. It will be described with reference to Figures 4a and 4b, but with reference to the previous drawings.

The LED device 150 according to an embodiment of the present invention includes a light emitting layer EL, a first electrode E1, a second electrode E2, and an insulating film PAS, and the light emitting layer EL includes a first semiconductor layer. (151), an active layer 152, and a second semiconductor layer 153. The LED element 150 emits light according to recombination of electrons and holes according to the current flowing between the first electrode E1 and the second electrode E2.

The first semiconductor layer 151 may be a p-type semiconductor layer and the second semiconductor layer 153 may be an n-type semiconductor layer, but for convenience, the first semiconductor layer 151 and the second semiconductor layer 153 will be described. In addition, it may be referred to as a p-type electrode or an n-type electrode according to the first electrode E1 and the second electrode E2 or according to the electrical connection relationship, that is, according to the semiconductor layer making the electrical connection, but similarly, for convenience, the first or second electrode I will explain with 2 electrodes. In addition, in this specification, the first semiconductor layer 151 and the second semiconductor layer 153 will be described as a p-type semiconductor layer and an n-type semiconductor layer, respectively, but the first semiconductor layer 151 and the second semiconductor layer 153 It may be an n-type semiconductor layer and a p-type semiconductor layer that are opposite to each other.

The first semiconductor layer 151 is provided on the active layer 152 and provides holes to the active layer 152 . The first semiconductor layer 153 according to an embodiment of the present invention may be made of a p-GaN-based semiconductor material, and the p-GaN-based semiconductor material may be GaN, AlGaN, InGaN, or AlInGaN. Here, as an impurity used for doping the second semiconductor layer 153, Mg, Zn, or Be may be used.

The second semiconductor layer 153 provides electrons to the active layer 152 . The second semiconductor layer 153 according to an embodiment of the present invention may be made of an n-GaN-based semiconductor material, and the n-GaN-based semiconductor material may be GaN, AlGaN, InGaN, or AlInGaN. Here, Si, Ge, Se, Te, or C may be used as an impurity used for doping the second semiconductor layer 151 .

The active layer 152 is provided on the second semiconductor layer 153 . The active layer 152 has a multi-quantum well (MQW) structure including a well layer and a barrier layer having a higher band gap than the well layer. The active layer 152 according to an embodiment of the present invention may have a multi-quantum well structure such as InGaN/GaN.

The first electrode E1 is electrically connected to the first semiconductor layer 151 and is connected to the drain electrode DE or source electrode SE of the driving transistor T2 which is a driving thin film pixel, and the second electrode E2 ) is connected to the common power line (CPL).

The aforementioned first electrode E1 may be a p-type electrode and the second electrode E2 may be an n-type electrode. This can be classified according to whether electrons or holes are supplied, that is, whether it is electrically connected to the p-type semiconductor layer or connected to the n-type semiconductor layer, but in this specification, the first electrode E1 and the second electrode ( E2) will be described.

Each of the first and second electrodes E1 and E2 according to an embodiment of the present invention is one of a metal material such as Au, W, Pt, Si, Ir, Ag, Cu, Ni, Ti, or Cr, or an alloy thereof. It may be made of materials including the above. Each of the first and second electrodes E1 and E2 according to another embodiment may be made of a transparent conductive material, and the transparent conductive material may be indium tin oxide (ITO) or indium zinc oxide (IZO). Not limited to this.

The insulating layer PAS is disposed to cover the outside of the LED element 150, is disposed to open at least a portion of the second electrode E2, is disposed to cover the active layer 152, and corresponds to the first electrode E1. It has an insulating film open area (P-Open).

The passivation layer PAS may be made of a material such as SiNx or SiOx and is disposed to cover the active layer 152 . The insulating film PAS is not intended when the electrodes are disposed so that the first electrode E1 and the second electrode E2 of the LED device 150 and the pixel electrode PE or the common electrode CE are electrically connected. Make sure no electrical connection between elements occurs.

The LED device 150 may be a light emitting device having a trapezoidal bottom surface on a plane, and the length of one surface on the side where the first electrode E1 is located is the longest side so that the area of the first semiconductor layer 151 is wide. It may be trapezoidal in shape.

If the width of the p-type semiconductor layer is wider than that of the n-type semiconductor layer included in the LED device 150, the luminous efficiency can be increased. In other words, since light efficiency can be increased by enlarging the area of the active layer 152 corresponding to the p-type semiconductor layer, the LED device 150 has a trapezoidal shape in which one surface corresponding to the p-type semiconductor layer of the LED device 150 is the long axis. ), it is possible to provide the LED element 150 with increased luminous efficiency.

Additionally, each of the second semiconductor layer 153, the active layer 152, and the first semiconductor layer 151 may be an LED device 150 formed by sequentially stacking on a semiconductor substrate. Here, the semiconductor substrate includes a semiconductor material such as a sapphire substrate or a silicon substrate. After the semiconductor substrate is used as a growth substrate for growing the second semiconductor layer 153, the active layer 152, and the first semiconductor layer 151, respectively, from the second semiconductor layer 153 by a substrate separation process. can be separated Here, the substrate separation process may be laser lift off or chemical lift off. Accordingly, as the semiconductor substrate for growth is removed from the LED device 150, the LED device 150 may have a relatively thin thickness, and thus may be accommodated in each sub-pixel SP.

5 is a schematic view of a semiconductor substrate used to form a light emitting device according to an embodiment of the present invention, and FIG. 6 is a partially enlarged view of region A of FIG. 5 .

As described above, the LED element 150 is formed on a semiconductor substrate (Wafer) and transferred to a display device to be driven as a light emitting element. In forming the LED element 150 on the semiconductor substrate (Wafer), it is advantageous to form the LED element 150 in a direction aligned in a straight line according to the pixel arrangement of the display device to be transferred.

In order to obtain the same number of LED elements 150 with increased luminous efficiency on the same semiconductor substrate (Wafer), the width of the side of the side with the first electrode E1 related to the luminous efficiency of the LED element 150 is enlarged. By forming the LED elements 150 on a substrate (Wafer), the luminous efficiency is increased, but the improved LED elements 150 of the same number as the rectangular LED elements 150 can be obtained. A detailed description of this will be described with reference to the following drawings.

7A to 7C are schematic plan views for explaining a light emitting device having increased luminous efficiency compared to a conventional light emitting device.

Referring to FIG. 7A, when a total of four conventional devices (LEDs) can be obtained in a unit area of a semiconductor substrate defined by a first horizontal length W1 and a first vertical length H1, referring to FIG. 7B , The LED element 150 is a trapezoidal LED element 150 in which the length of one side is increased, and the LED element 150 in the unit area of the semiconductor substrate defined by the second horizontal length W2 and the second vertical length H2 ) can get a total of four.

At this time, when the first horizontal length W1 and the second horizontal length W2 are substantially the same, and the first vertical length H1 and the second vertical length H2 are substantially the same, the LED element 150 ) is a light emitting device having an increased area on the side of the first electrode E1, and may be an LED device 150 having higher luminous efficiency than the conventional device (LED).

Referring to FIG. 7C, the LED device 150 formed on the semiconductor substrate is transferred to the substrate of the display device through a transfer process. This transfer process involves a first transfer process and a second transfer process using a transfer substrate for transfer. It can be divided into

For the plurality of LED elements 150 on one semiconductor substrate, the same transfer process is repeatedly performed because the transfer is divided in consideration of the spacing of the pixels instead of being transferred at once. In the repeated transfer process, the process stability of the transfer process may be affected depending on the position where the LED device 150 is disposed on the semiconductor substrate.

In one embodiment of the present invention, as shown, the first electrode E1 of the neighboring LED element 150 faces the first electrode E1 of the neighboring LED element 150, the second electrode E2 ) to face the second electrode E2 of the neighboring LED element 150, the stability of the transfer process of transferring the LED element 150 can be improved.

8A and 8B are schematic plan views illustrating a light emitting element having a similar light emitting efficiency and having an increased number of chamfers.

Referring to FIGS. 8A and 8B , when a total of four conventional devices (LEDs) can be obtained in the unit area of the semiconductor substrate defined by the first horizontal length (W1) and the first vertical length (H1), the conventional device The area of the semiconductor substrate from which four LED elements 150 having a vertical length h2 substantially equal to the vertical length h1 of the LED can be obtained is the second horizontal length W2 and the second vertical length H2 ). In the case of the LED device 150 having one side length increased, the second vertical length H2 is smaller than the first vertical length H1. That is, the LED device 150 having substantially the same light emission luminance can be formed on a semiconductor substrate having a smaller area than the conventional device (LED), and the number of LED devices 150 that can be obtained on the semiconductor substrate having the same area is reduced. It increases.

As described above, by increasing the number of LED elements 150 that can be obtained on a semiconductor substrate of the same area, the cost of manufacturing a display device having the LED elements 150 can be reduced.

9A and 9B are schematic diagrams for explaining a process of transferring a light emitting element.

The LED element 250 is grown on a semiconductor wafer (wafer) and patterned to complete the individual LED element 250 . The LED element 250 on the semiconductor substrate (wafer) is primarily transferred to the transfer substrate (Donor). ), the LED element 250 can be implanted on the transfer substrate (Donor) by irradiating the back surface of the semiconductor substrate (wafer) to separate the LED element 250 and adhering it to the transfer substrate (Donor).

The transfer substrate 250 may be a substrate made of a high-adhesive material such as PDMS (Polydimethylsiloxane) as a polymer material, and protrusions may be disposed at a distance corresponding to a distance (pixel pitch) between pixels of a display device. . The protusion allows the LED element 250 to be stably implanted on the transfer substrate (Donor), and can be removed depending on the material of the transfer substrate (Donor) or process conditions.

In this way, when the LED element 250 is implanted on the transfer substrate 250, a step of aligning the transfer substrate (Donor) and the semiconductor substrate (wafer) is required. 150) and the directions of the first electrode E1 and the second electrode E2 may be different, a method of rotating the semiconductor substrate Wafer and the transfer substrate Donor by 180 degrees may be used to match them.

Alternatively, the display device may be configured by changing the electrode connection method so that there is no problem in connecting the electrodes even when the LED elements 150 having electrodes in different directions are disposed in the display device.

Thereafter, a step of transferring the LED element 250 transferred to the transfer substrate (Donor) to a light emitting element of an actual display device is performed.

First, a step of aligning the transfer substrate (Donor) and the substrate 210 is performed, and a step of transplanting the LED device 250 to the substrate 210 is performed. When the substrate 210 and the donor are brought into contact, the adhesive member 114 on the substrate 210 adheres to the lower surface of the LED element 250 as described in the configuration shown in FIG. 3 . By the adhesive member 114, the substrate 210 and the LED element 250 have a greater adhesive force than the transfer substrate Donor, so that the LED element 250 is transferred to the substrate 210.

Although the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and may be variously modified and implemented without departing from the technical spirit of the present invention. . Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. The protection scope of the present invention should be construed by the claims, and all technical ideas within the equivalent range should be interpreted as being included in the scope of the present invention.

100: light emitting display device
110: substrate
150: LED element
151: first semiconductor layer
152: active layer
153: second semiconductor layer
154, 160: structure
E1: first electrode
E2: second electrode

Claims (13)

A substrate made of glass or plastic material;
a thin film transistor disposed on the substrate and including a gate electrode and a source/drain electrode;
a protective layer covering the thin film transistor;
an adhesive member disposed on the protective layer;
an n-type semiconductor layer with a lower surface contacting the adhesive member; a p-type semiconductor layer located in a partial region on the n-type semiconductor layer; an n-type electrode positioned on the n-type semiconductor layer; a p-type electrode positioned on the p-type semiconductor layer; and an active layer disposed between the n-type semiconductor layer and the p-type semiconductor layer and having an inclined surface on one side surface adjacent to the n-type electrode;
an insulating film exposing at least a portion of the light emitting element while covering the outside of the light emitting element;
a reflective layer overlapping the lower portion of the light emitting device;
a pixel electrode disposed on the substrate and connected to the p-type electrode; and
a wiring electrode disposed on the substrate and connected to the n-type electrode; contains
The display device of claim 1 , wherein a bottom surface of the light emitting element has a trapezoidal shape on a plane, and a length of one side surface where the p-type electrode is located is longer than a length of another side surface where the n-type electrode is located.
According to claim 1,
The n-type electrode and the p-type electrode are on the same side of the display device.
According to claim 1,
The display device of claim 1 , wherein the substrate includes at least one driving element, and the pixel electrode is connected to the driving element.
According to claim 1,
In the light emitting element, alignment directions of the p-type electrode and the n-type electrode of adjacent light emitting elements are different from each other.
According to claim 1,
The insulating layer may further include a first open area exposing at least a portion of the n-type semiconductor layer on which the n-type electrode is disposed, and a second open area exposing at least a portion of the p-type electrode.
According to claim 1,
The insulating layer is disposed to cover the inclined surface of the active layer.
According to claim 1,
The insulating layer includes silicon nitride (SiNx) or silicon oxide (SiOx).
A substrate made of glass or plastic material;
a thin film transistor disposed on the substrate and including a gate electrode and a source/drain electrode;
a protective layer covering the thin film transistor;
an adhesive member disposed on the protective layer;
an n-type semiconductor layer with a lower surface contacting the adhesive member; a p-type semiconductor layer located in a partial region on the n-type semiconductor layer; an n-type electrode positioned on the n-type semiconductor layer; a p-type electrode positioned on the p-type semiconductor layer; and an active layer disposed between the n-type semiconductor layer and the p-type semiconductor layer and having an inclined surface on one side surface adjacent to the n-type electrode;
an insulating film exposing at least a portion of the p-type electrode while covering the outside of the light emitting element;
a reflective layer overlapping the lower portion of the light emitting device;
a pixel electrode disposed on the substrate and connected to the p-type electrode; and
a wiring electrode disposed on the substrate and connected to the n-type electrode; including,
The inclined surface of the active layer has a length of one side corresponding to the p-type semiconductor layer longer than a length of the other side corresponding to the n-type semiconductor layer.
According to claim 8,
The n-type electrode and the p-type electrode are on the same side of the display device.
According to claim 8,
The display device of claim 1 , wherein the substrate includes at least one driving element, and the pixel electrode is connected to the driving element.
According to claim 8,
In the light emitting element, alignment directions of the p-type electrode and the n-type electrode of adjacent light emitting elements are different from each other.
According to claim 8,
The insulating layer may further include a first open area exposing at least a portion of the n-type semiconductor layer on which the n-type electrode is disposed, and a second open area exposing at least a portion of the p-type electrode.
According to claim 8,
The insulating layer is disposed to cover the inclined surface of the active layer.

Images