KR20200075364A - Display apparatus and manufacturing method of the same - Google Patents

Abstract

According to one embodiment of the present invention, a display device with improved luminous efficiency by including a slit pattern and a reflective layer with a slit pattern. A driving element and a light emitting device are disposed on a substrate. A planarization layer is disposed to cover the light emitting device, and the planarization layer includes a slit pattern. The slit pattern is disposed adjacent to the light emitting device, disposed to surround the light emitting device, and having a reflective layer disposed on one inclined surface inside the slit pattern. The reflective layer of the slit pattern disposed to surround the light emitting device adjusts n optical path of light emitted from the light emitting device, thereby increasing the light efficiency of the light emitting device. In the display device according to one embodiment of the present invention, the slit pattern having the reflective layer is disposed to adjacently surround the light emitting device, thereby improving luminous efficiency of the display device.

Description

Display device and manufacturing method thereof {DISPLAY APPARATUS AND MANUFACTURING METHOD OF THE SAME}

The present invention relates to a display device and a method for manufacturing the same, and more particularly, to provide a display device having improved light efficiency by disposing a slit pattern adjacent to a pixel in the display device and a reflective layer inside the slit pattern, and a method for manufacturing the same. .

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

The display device may be divided into a reflective display device and a light emitting display device. The reflective display device is a display device in which information emitted from natural light or external light of the display device is reflected on the display device to display information. The display device is a method in which a light emitting element or a 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 device may use a light emitting device that can emit various wavelengths of light, or a color filter that can change the wavelength of light emitted along with a light emitting device that emits white or blue light.

As described above, in order to realize an image as a display device, a plurality of light emitting devices are arranged on a substrate of the display device, and a driving device that supplies a driving signal or a driving current to control each light emitting device to emit light individually is a light emitting device. It is arranged on the substrate together, and the plurality of light-emitting elements disposed on the substrate are analyzed according to the arrangement of the information to be displayed to be displayed on the substrate.

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

Typical display devices using thin film transistors include liquid crystal displays and organic light emitting displays. Among them, the liquid crystal display device is not a self-emission method, and therefore a backlight unit disposed to emit light at the bottom (back) of the liquid crystal display device is required.

Due to the additional backlight unit, the thickness of the liquid crystal display device is increased, and there are limitations in implementing the display device in various types of designs such as flexible or circular shapes, and luminance and response speed may be reduced.

On the other hand, a display device having a self-emission element can be implemented thinner than a display device having a light source, and has an advantage of implementing a flexible and collapsible display device.

A display device having 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 device as a light-emitting element, such as an organic light-emitting display device or a self-display such as a micro-LED display device Since the device does not require a separate light source, it can be used as a thinner or various types of display devices.

However, an organic light emitting display device using an organic material does not require a separate light source, but it is easy to generate defective pixels due to moisture and oxygen, and various technical ideas for minimizing oxygen and moisture penetration are additionally required.

Regarding the above-mentioned problems, recently, research and development on a display device using a micro light emitting diode (Micro light emitting diode) of a fine size has been conducted, and such a light emitting display device has high image quality and high reliability. It is spotlighted as a next-generation display device.

The LED element is a semiconductor light emitting element that uses a property of emitting light when a current is applied to the semiconductor, and is widely used in lighting, TV, and various display devices. The LED element is composed of an n-type semiconductor layer and a p-type semiconductor layer, and an active layer therebetween. When an electric current is passed, electrons are present in the n-type semiconductor layer portion, holes are present in the p-type semiconductor layer portion, and the active layer combines to emit light.

In order to realize a light emitting display device in which an LED element is used as a light emitting element of a unit pixel, there are some technical requirements. First, crystallizing an LED element on a semiconductor wafer substrate such as sapphire or silicon (Si), and moving a plurality of crystallized LED chips to a substrate having a driving element, but at a position corresponding to each pixel. An elaborate transfer process for locating LED elements is required.

LED elements can be formed using inorganic materials, but need to be formed by crystallization. To crystallize inorganic materials such as GaN, inorganic materials must be crystallized on a substrate capable of inducing crystallization. The substrate capable of efficiently inducing crystallization of the inorganic material is a semiconductor substrate, and the inorganic material must be crystallized on the semiconductor substrate as described above.

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

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

Currently, the aforementioned sapphire substrate is mainly used as a substrate, and recently, research activities on substrates based on GaN have been actively conducted.

Due to the high price of the semiconductor substrate required to crystallize the inorganic material such as GaN constituting the LED light emitting device on the semiconductor substrate, a large amount of light emitting pixels of the display device, rather than the LED as a light source used for simple lighting or backlight. When the LED is used, there is a problem in that manufacturing cost increases.

In addition, as described above, the LED element formed on the semiconductor substrate requires a step of transferring to the substrate constituting the display device. In this process, it is difficult to separate the LED element formed on the semiconductor substrate, and it is separated. There are also many difficulties and problems when properly transplanting an LED device to a desired point.

In transferring the LED element formed on the semiconductor substrate to the substrate implementing the display device, a method 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 each element Various transcription methods such as methods can be used, and research activities on various transcription methods have been conducted.

As described above, the transfer process is related to the productivity of the process of implementing the display device, and for mass production, it is inefficient to move the LED elements one by one.

Accordingly, a plurality of LED elements are separated from a semiconductor substrate by using a transfer substrate using a polymer material, and the substrate is configured in a display device, particularly a driving element disposed in a thin film transistor and a pad electrode connected to a power electrode. A transfer process or construction method has become necessary.

During the transfer process described above or during a subsequent process following the transfer process, the LED device may be moved or transferred according to the conditions of vibration or inferiority, such that the LED device may be reversed and transferred, such that defects may be generated. And had a lot of trouble recovering.

For example, the transfer process of the LED device will be described with an example of a general transfer process. An LED element is formed on a semiconductor substrate and an electrode is formed on the semiconductor layer to complete it as an individual LED element. Thereafter, the semiconductor substrate is brought into contact with the PDMS substrate (hereinafter referred to as a transfer substrate) to move the LED element to the transfer substrate. Since the transfer substrate needs to transfer the LED element formed on the semiconductor substrate to the transfer substrate in consideration of the distance of the pixel distance of the pixels, the transfer element receives the LED element on the transfer substrate in consideration of the pixel distance of the display device. The projection shape for the projecting is arranged.

By irradiating the laser with the LED element through the back surface of the semiconductor substrate, the LED element is separated from the semiconductor substrate. In the process of irradiating the laser, when the LED element is separated from the semiconductor substrate, the GaN material of the semiconductor substrate is applied to the high energy of the laser. Due to the concentration of energy, a rapid expansion may occur physically, and thus, an impact may occur. (This is called the primary warrior.)

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

When a 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 adhesion between the transfer substrate and the LED element is made smaller than the adhesion 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 warrior)

The size of the semiconductor substrate and the substrate constituting the display device are basically different, and the substrate constituting the display device is usually large. Due to the difference in area and size, if the above-described primary and secondary transfers are repeatedly performed for each area of the substrate of the display device, the LED elements corresponding to each pixel constituting the display device can be transferred. .

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

The LED element is composed of a compound semiconductor such as GaN, and can inject high current due to the characteristics of inorganic materials, thereby realizing high luminance, and has high reliability due to low environmental impact such as heat, moisture, and oxygen.

In addition, the LED device has an advantage of being capable of displaying a high-brightness image and having a low power consumption because the internal quantum efficiency is higher than that of the organic light emitting diode display by 90%.

In addition, unlike an organic light emitting display device, since an inorganic material is used, there is no need for a separate encapsulation film or encapsulation board for minimizing the penetration of oxygen and water at a level of minimal influence of oxygen and moisture. There is an advantage of minimizing the non-display area of the display device, which is a margin area that can be generated by arrangement.

As described above, in a display device using an LED element as a pixel, there is an advantage that a display device having a low power consumption at a level of 90% of internal quantum efficiency can be implemented, while the LED device is generated on a semiconductor wave and then displayed. Due to the problem of undergoing the process of transplanting to the display device, there is a problem in that it takes a high cost along with process difficulty in manufacturing the display device.

In addition, the LED element on the substrate has high energy efficiency compared to energy, but it is necessary to collect light in a specific direction or adjust the light path in order to perform the function of a pixel of a display device.

Accordingly, in recent research activities, efforts have been made to develop a display device with improved light efficiency by efficiently adjusting the optical path in a display device using the above-described LED element as a pixel.

As described above, the display device in which the LED element is used does not require an encapsulation film or encapsulation board, thereby minimizing the bezel area, and is advantageous in constructing a modular display device using a plurality of display devices. However, there is a need to further increase the light efficiency of LED elements used as elements of such display devices.

The LED element in the display device emits light without directionality due to its structural characteristics, and thus has a problem in that it is difficult to control the direction of the emitted light, and thus there is a problem that light efficiency may be lowered. Accordingly, the inventors of the present invention invented a display device capable of increasing the light efficiency of light emitted from an LED element and a method for manufacturing the same.

A problem according to an embodiment of the present invention is to provide a display device having a slit pattern disposed adjacent to a pixel and a reflective layer disposed within the slit pattern, and a manufacturing method thereof, so as to improve light efficiency of a light emitting device that emits light.

A problem according to an embodiment of the present invention is a display device capable of disposing a slit pattern on a flat film surrounding a light emitting device by using a pixel electrode as a mask for an exposure process in order to arrange the above-described slit pattern adjacent to a pixel. And a method for manufacturing the same.

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

A display device having increased light efficiency by providing a slit pattern and a reflective layer according to an embodiment of the present invention is provided. A driving element is disposed on the substrate and a light emitting element electrically connected to the driving element is disposed. The light emitting element is covered with a planarization layer, and a pixel electrode is disposed on the planarization layer in order to have an electrical connection with the driving element. A slit pattern is disposed on the planarization layer, and is disposed to surround the light emitting element. A reflective layer may be disposed on an inclined surface of one side of the slit pattern to control the path of light emitted from the light emitting device, thereby providing a display device with increased light efficiency.

A method of manufacturing a display device according to an embodiment of the present invention is provided. A driving element and a light emitting element are disposed on the substrate. After the light emitting element is disposed, a planarization layer covering the light emitting element is disposed, and the electrode portion of the driving element and the light emitting element is opened. A pixel electrode connecting the driving element and the light emitting element is disposed on the planarization layer. A slit pattern is formed in the planarization layer around the light emitting element. The step of disposing the slit pattern includes etching a part of the pixel electrode and disposing the slit pattern on the planarization layer exposed by opening the pixel electrode. After the slit pattern is disposed, a reflective layer is formed inside the slit pattern to control the light emission direction of the light emitting device, thereby providing a display device with improved light efficiency.

According to an embodiment of the present invention, the light efficiency of the light emitting element can be improved by arranging the slit pattern and the reflective layer adjacent to the light emitting element in the display device.

In addition, by using the pixel electrode as a mask in the step of arranging the slit pattern and the reflective layer, it is possible to increase the process stability and stably implement the fine shape of the slit pattern, thereby improving the productivity of the display 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 following description.

The subject matter to be solved above, the problem solving means, and the contents of the invention described in the effects do not specify the essential features of the claims, so the scope of the claims is not limited by the contents described in the contents of the invention.

1 is a schematic diagram illustrating a display device according to an embodiment of the present invention.
2 is a schematic partial enlarged view illustrating a pixel illustrated in FIG. 1 for describing a pixel in a display device according to an exemplary embodiment of the present invention.
3 is a schematic cross-sectional view taken along line A-A'in FIG. 2 and is a schematic view for explaining a display device having a slit pattern according to an embodiment of the present invention.
4 is a schematic diagram illustrating a light emitting device in a display device according to an exemplary embodiment of the present invention.
5 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the present invention.
6A to 6L are schematic cross-sectional views illustrating a method of manufacturing a display device according to an exemplary embodiment of the present invention.
7 is a schematic diagram illustrating a display device according to another embodiment of the present invention.
8A to 8K are schematic cross-sectional views illustrating a method of manufacturing a display device according to another exemplary embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving them will be clarified with reference to embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only the present embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention pertains. It is provided to fully inform the holder of the scope of the invention, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for describing the embodiments of the present invention are exemplary, and the present invention is not limited to the illustrated matters. The same reference numerals refer to the same components throughout the specification. In addition, in the description of the present invention, when it is determined that detailed descriptions of related known technologies may unnecessarily obscure the subject matter of the present invention, detailed descriptions thereof will be omitted. When'include','have','consist of', etc. mentioned in this specification are used, other parts may be added unless'~man' is used. When a component is expressed as a singular number, the plural number is included unless otherwise specified.

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

In the case of the description of the positional relationship, for example, when the positional relationship of two parts is described as'~top','~upper','~bottom','~side', etc.,'right' Alternatively, one or more other parts may be located between the two parts unless'direct' is used.

In the case of a description of a time relationship, for example,'after','following','~after','~before', etc., when the temporal preliminary relationship is described,'right' or'directly' It may also include cases that are not continuous unless' is used.

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

Each of the features of the various embodiments of the present invention may be partially or wholly combined or combined with each other, technically various interlocking and driving may be possible, and each of the embodiments may be independently performed with respect to each other or may be implemented together in an association relationship. It might be.

Hereinafter, various configurations of a display device having improved light efficiency by a slit pattern and a reflective layer according to an embodiment of the present invention will be described with reference to the accompanying drawings.

1 is a schematic diagram illustrating a display device according to an embodiment of the present invention.

Referring to FIG. 1, a display area AA and a non-display area IA having a plurality of unit pixels UP defined on a substrate 110 are defined in the display device 100 according to an exemplary embodiment of the present invention. It includes the substrate 110.

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 red, blue, and green. Subpixels SP1, SP2, and SP3 that emit light may be included, but are not limited thereto, and may include subpixels that emit light such as white.

The substrate 110 is a thin film transistor array substrate, which may be made of a glass or plastic material, or may be a substrate that is divided into two or more layers or a combination 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, and 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 has a first reference pixel distance preset along the X-axis direction and is disposed in the display area AA to have a second preset reference pixel distance along the Y-axis direction. The first reference pixel distance may be defined as the distance between the center portions of each adjacent unit pixel (UP), and the second reference pixel distance may be defined as the distance between each unit pixel (UP) adjacent to the reference direction similar to the first reference pixel distance. It can be defined as the distance between.

Meanwhile, the distance between the sub-pixels SP1, SP2, and SP3 forming the unit pixel UP is also defined as the first reference sub-pixel distance and the second reference sub-pixel distance, similar to the first reference pixel distance and the second reference pixel distance. Can be.

In the light emitting display device 100 including the light emitting device, the width of the non-display area IA may be smaller than the above-described pixel distance or sub-pixel distance, and a non-display area having a length equal to or less than the pixel distance or sub-pixel distance ( When a multi-screen display device is configured with the light-emitting display device 100 having the IA), since the non-display area IA is smaller than the pixel distance or sub-pixel distance, a multi-screen display device having substantially no bezel area can be implemented. do.

As described above, in order to realize a multi-screen display device in which the bezel area is substantially or minimized, the light emitting display device 100 includes a first reference pixel distance and a second reference pixel distance within the display area AA, Although the first reference sub-pixel distance and the second reference sub-pixel distance may be kept constant, the display area AA is defined as a plurality of zones, and the above-described distance lengths in each zone are different from each other, but the non-display area ( By making the pixel distance of the area adjacent to IA) wider than other areas, the size of the bezel area can be made smaller than the pixel distance.

As described above, the light emitting display device 100 having different pixel distances may distort an image, so image processing is performed in a manner that compares with adjacent areas in consideration of the set pixel distance and samples image data. The bezel area can be minimized while minimizing distortion.

FIG. 2 is a schematic partial enlarged view illustrating a pixel illustrated in FIG. 1 for describing a pixel in a display device according to an exemplary embodiment.

As described above, the pixel is composed of a plurality of sub-pixels, and the sub-pixel includes at least one light emitting element. Hereinafter, a sub-pixel will be referred to as a pixel.

Referring to FIG. 2, the pixel SP includes a circuit portion SP-c and a pixel portion SP-p. Although briefly illustrated in FIG. 2, the circuit unit SP-c may include a driving element, etc. for supplying current to the light emitting element 150 according to an electrical signal, and may include a capacitor, etc., electrically connected to the driving element. There are various electrodes that provide electrical connection or current between them.

The current is supplied to the pixel portion SP-p through the circuit portion SP-c, and for this purpose, the pixel electrode 121 and the common electrode 122 in the pixel portion SP-p are the circuit portion SP-c. It can be connected to the components, or wiring electrodes to supply current.

The pixel part SP-p includes a light emitting element 150 and includes a first connection electrode 131 electrically connected between the pixel electrode 121 and the first electrode E1 on the light emitting element 150. , A second connection electrode 132 electrically connected to the common electrode 122 and the second electrode E2 on the light emitting device 150.

A slit pattern 140 is disposed adjacent to the light emitting device 150 around the light emitting device 150. The slit pattern 140 includes a reflective layer 160, and is disposed to surround the light emitting device 150 so that the light emitting device ( The path of light emitted from 150 may be adjusted in the direction of the light emitting device 150, and thus the light efficiency of the light emitting device 150 may be increased.

The above-described circuit part SP-c and the pixel part SP-p are shown separately for explanation, and components included in each are shared or arranged with each other in the circuit part SP-c or the pixel part SP-p. The circuit portion SP-c and the pixel portion SP-p may overlap.

3 is a schematic cross-sectional view taken along line A-A'in FIG. 2 and is a schematic view for explaining a display device having a slit pattern according to an embodiment of the present invention.

The display device according to an exemplary embodiment of the present invention may include a light emitting device 150 and various electrodes as well as a stacked structure of various layers on the substrate 110.

Although not shown on the substrate 110, a driving element such as a thin film transistor and an interlayer protective layer 111 for protecting the same may be disposed, and the driving element protective layer 112 may be disposed.

As described with reference to the previous drawings, the pixel electrode 121 and the common electrode 122 are disposed to supply current according to an electrical signal to the light emitting device 150, and the connection between the pixel electrode 121 and the light emitting device 150 is the first connection electrode. 131 and the second connection electrode 132.

The pixel electrode 121 is usually an anode electrode that supplies electrons, and the common electrode 122 can be said to be an electrode that supplies holes, but in some cases, they can be interchanged. This may be changed depending on whether the first electrode E1 and the second electrode E2 connected to the light emitting device 150 are n-type electrodes or p-type electrodes.

The pixel electrode 121 and the common electrode 122 may be electrodes of the same material as the source electrode and the drain electrode constituting the driving element, and may be disposed at the same stage as the source electrode and the drain electrode in the process of arrangement.

The pixel electrode 121 and the common electrode 122 are disposed on the driving element protective layer 112 and may be multi-layered electrodes, for example, the same material as the reflective electrode 123 under the light emitting device 150. It may be an electrode of a multi-layer structure made by adding an electrode layer of.

The light emitting device 150 is supplied with electrons and holes to emit light. When emitting light, the light emission direction is not specified, so light can be emitted in all directions. Therefore, light is emitted to the lower portion of the light emitting device 150 The reflective electrode 123 may be disposed under the light emitting device 150 to reflect light in the upper direction of the light emitting device 150 to increase light efficiency.

The reflective electrode 123 may be Al, Ag, Au, Pt, or Cu, but is not limited thereto. As described above, the reflective electrode 123 is made of a material that reflects light, and most of the reflective electrode 123 may be composed of a conductive material, and thus, when the conductive material is floating without being connected to another ground electrode, the influence of several different electrical circuits As the induced charge may accumulate, it may cause static electricity or the like and may affect other electrical circuits, so that it is arranged to be connected to the first ground electrode 124.

The first ground electrode 124 may make an electrical connection with other circuit wiring so as to discharge charges accumulated on the reflective electrode 123 to the outside, and may be composed of the same electrode as the source electrode or the drain electrode constituting the driving element. Can.

The driving element protection layer 112 is disposed over the entire surface of the substrate 110 to cover the pixel SP. The driving element protection layer 112 provides a flat surface while protecting circuit elements in the pixel portion SP-p including the circuit portion SP-c. The driving element protective layer 112 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 acrylic material for convenience of the process. Do.

The adhesive layer 113 is disposed on the driving element protective layer 112. The adhesive layer 113 may be an adhesive material such as resin, and is disposed to fix the light emitting device 150.

The light emitting element 150 is disposed on the adhesive layer 113. The light emitting device 150 will emit light by receiving electrons and holes, as will be described later, and includes a first electrode E1 and a second electrode E2 to receive electrons and holes.

The light emitting device 150 is mounted on each of a plurality of sub-pixels SP1, SP2, and SP3. The light emitting device 150 according to an embodiment of the present invention may be an optical 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 is not limited thereto.

The planarization layer 114 is disposed on the adhesive layer 113 and the driving element protection layer 112 to cover the light emitting device 150. That is, the planarization layer 114 is disposed to have a thickness sufficient to cover both the front surface of the driving element protective layer 112, the place where the light emitting device 150 is disposed, and the remaining front surface.

The planarization layer 114 may be composed of a single layer and may be a planarization layer 114 having a multi-layer structure. As such, the planarization layer 114 provides a flat surface on the driving element protection layer 112. In addition, the planarization layer 114 serves to fix the position of the light emitting device 150.

The planarization layer 114 is provided with a common electrode contact hole (CCH) for opening the common electrode 122 and a pixel electrode contact hole (PCH) for opening the pixel electrode 121. In addition, the planarization layer 114 is disposed to open the first electrode E1 and the second electrode E2 in the light emitting device 150.

The open pixel electrode 121 and the first electrode E1 of the light emitting device 150 are electrically connected by the first connection electrode 131, and the open common electrode 122 is made of the light emitting device 150. It is electrically connected by the second electrode E2 and the second connection electrode 132. The first connection electrode 131 and the second connection electrode 132 are disposed on the planarization layer 114 and may be made of a transparent conductive material. The transparent conductive material may be ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), but is not limited thereto.

Meanwhile, a slit pattern 140 is disposed on the planarization layer 114. The slit pattern 140 may be composed of fine slits having a width of 2 to 3 μm, and is disposed adjacent to the light emitting device 150 but is arranged to surround the light emitting device 150.

The reflective layer 160 is disposed inside the slit pattern 140. The reflective layer 160 may be disposed on one side of the inside of the slit pattern 140. Since the slit pattern 140 is composed of fine slits, the inclination of the substrate 110 and the slit pattern 140 may be 70 degrees or more. The angle formed between the reflective layer 160 and the substrate 110 may be 70 degrees or more.

The reflective layer 160 may be disposed on either side of the inside of the slit pattern 140 as described above, or may be disposed to fill the inside of the slit pattern 140. The reflective layer 160 may be made of a material such as Al, Ag, Au, Pt, or Cu, and is based on the light emitting device 150 to reflect light emitted from the light emitting device 150 to the top of the substrate 110. Thus, the angle formed with the substrate 110 may be an obtuse angle.

The reflective layer 160 in the slit pattern 140 may be configured to be electrically connected to the first connection electrode 131 or the second connection electrode 132. When the reflective layer 160 in the slit pattern 140 is not electrically connected to the first connection electrode 131 or the second connection electrode 132 described above, it is floated to cause static electricity, such as the reflection electrode 123. Since it is possible to be connected to the first connection electrode 131 or the second connection electrode 132, it is preferable to ground. However, in order to ground the reflective layer 160, it is not necessary to be necessarily connected to the first connection electrode 131 or the second connection electrode 132, and in some cases, it may be electrically connected to the first ground electrode 124.

On the other hand, it can be seen that the first connection electrode 131 is electrically disconnected by the slit pattern 140, which is the reflective layer 160 disposed inside the slit pattern 140, any one of the slit pattern 140 When disposed only on the side surface, the electrical connection of the first connection electrode 131 may be broken. In order to compensate for this electrical connection, as shown in FIG. 2, the slit pattern 140 has an open area 141 defined so that the first connection electrode 131 and the second connection electrode 132 can be electrically connected. do.

The open area 141 is a reflective layer 160 such that the first connecting electrode 131 and the second connecting electrode 132 are not electrically shorted by the slit pattern 140 and the reflective layer 160 inside the slit pattern 140. ).

4 is a schematic diagram illustrating a light emitting device in a display device according to an exemplary embodiment of the present invention.

The light emitting 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 is a first semiconductor layer 151, an active layer 152, and a second semiconductor layer 153. The light emitting device 150 emits light according to recombination of electrons and holes according to a current flowing between the first electrode E1 and the second electrode E2.

The first semiconductor layer 151 is 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, the first electrode (E1) and the second electrode (E2) or according to the electrical connection relationship, that is, depending on the semiconductor layer forming the electrical connection may be referred to as a p-type electrode or an n-type electrode, but for convenience, the first or first 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 p-type semiconductor layers and n-type semiconductor layers, respectively, but the first semiconductor layer 151 and the second semiconductor layer 153 are Each may be opposite n-type semiconductor layers and p-type semiconductor layers.

The first semiconductor layer 151 is disposed on the active layer 152 to provide holes in 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, Mg, Zn, or Be may be used as an impurity used for doping the second semiconductor layer 153.

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 disposed on the second semiconductor layer 153. The active layer 152 has a multi-quantum well (MQW) structure having 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 may be a p-type electrode, and the second electrode E2 may be an n-type electrode. This may be classified according to whether electrons or holes are supplied, that is, electrically connected to a p-type semiconductor layer or connected to an n-type semiconductor layer, but in this specification, the first electrode E1 and the second electrode ( E2).

Each of the first and second electrodes E1 and E2 according to an embodiment of the present invention is one of metal materials such as Au, W, Pt, Si, Ir, Ag, Cu, Ni, Ti, or Cr, and alloys thereof It may be made of a material containing 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 ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). It is not limited to this.

The insulating layer PAS is disposed to cover the outside of the light emitting device 150 and has an insulating layer open area P-Open to open at least a portion of the first electrode E1 and the second electrode E2. The insulating layer PAS may be formed of a material such as SiNx or SiOx and is disposed to cover the active layer 152.

The insulating layer PAS prevents unnecessary electrical connection between the first electrode E1 and the second electrode E2 in the light emitting device 150 between other elements.

Additionally, each of the second semiconductor layer 153, the active layer 152, and the first semiconductor layer 151 may be a light emitting device 150 formed by being sequentially stacked on a semiconductor substrate. Here, the semiconductor substrate includes a semiconductor material such as a sapphire substrate or a silicon substrate. The semiconductor substrate is used as a growth substrate for growing each of the second semiconductor layer 153, the active layer 152, and the first semiconductor layer 151, and then 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 growth semiconductor substrate is removed from the light emitting device 150, the light emitting device 150 may have a relatively thin thickness, and thus may be accommodated in each pixel SP.

5 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the present invention. Description of the manufacturing process described with reference to FIG. 5 but not within the main scope of the present invention will be briefly described or omitted.

A driving element and a light emitting element are disposed on the substrate. (S110) When arranging a driving element on a substrate, the pixel electrode and the common electrode, such as a pixel electrode and a common electrode for electrical connection between the driving element and the light emitting element, are the same as the source electrode or the drain electrode constituting the driving element. Place the electrodes. The light emitting device may be accompanied by a process of forming an adhesive layer on the substrate and arranging the light emitting device but pressing it so that the light emitting device does not detach and adhesion is smoothly performed.

Then, a step of disposing a planarization layer and a connection electrode covering the light emitting element is performed. (S120) The planarization layer may be formed twice, so that it is disposed at a height sufficiently covering the light emitting device. In the step of arranging the planarization layer, an open area is disposed on the planarization layer to open the pixel electrode and the common electrode, but the open area is opened to be inclined to a certain degree in order to facilitate electrical connection in the process of arranging connection electrodes. Also, the first electrode and the second electrode in the light emitting device may be patterned together to open.

The flattening layer is uncured after placing an organic material in an uncured state and then flattening the upper part of the planarizing layer through a spin coating method, and then using a mask to separate the area to be cured and the area to be opened and cured. The planarization layer may be disposed by removing the region, and the material used may vary depending on a method of curing.

In addition, a connection electrode is formed on the planarization layer formed as described above. The connection electrode is arranged to make electrical connection with the open electrodes in the open area of the planarization layer such as the pixel electrode and the common electrode.

A step of forming a slit pattern in the planarization layer around the light emitting device is performed. (S130) The step includes removing at least a portion of the connection electrode to place the slit pattern on the planarization layer (S131) and patterning the connection electrode into a first connection electrode and a second connection electrode (S132). can do.

In order to arrange the slit pattern on the planarization layer, a dry etching method in which an etching gas is injected after the photoresistor is disposed may be used. At this time, in order to place the slit having a fine width such as a slit pattern on the planarization layer, it may not be possible with the photoresist alone, because the photoresist may cause the area opened by the etching gas to be etched and pushed together from side to side. All.

In order to minimize damage to the open area of the photoresist by the etching gas, the connecting electrode is first etched using an etching solution (Wet etch), and the dry opening of the connecting electrode as described above can complete the slit pattern. There will be.

Thereafter, the connection electrode is patterned to be separated into a first connection electrode and a second connection electrode. (S132)

A display device is completed by performing a step of forming a reflective layer on one side of the slit pattern. (S140) Since the slit pattern is disposed to surround the light emitting device, a reflective layer is formed inside the slit pattern so that the light efficiency of the light emitting device is increased. In the process of forming the reflective layer, an opaque reflective material such as Al, Ag, or Cu is deposited on the entire surface using a method of sputtering, and a photoresist is patterned and placed to remove unnecessary reflective layers using a solution. A reflective layer may be disposed inside.

On the other hand, in another embodiment of the present invention, in order to realize a display device having a structure for smoothing the electrical connection of the connection electrode, the steps of disposing the connection electrode on the reflective layer may be further performed.

To explain this further, it is as follows. After the step of forming the reflective layer on one side of the slit pattern, the connection electrode is removed and the step of filling the inside of the slit pattern with a planarization layer (S141).

After the step of flattening the slit pattern is performed to further facilitate the electrical connection of the connection electrode, a step of disposing the connection electrode on the planarization layer is performed. (S142) The connection electrode is first and second connection electrodes. The patterning step may be performed. (S143)

As described above, the connection electrode is separately disposed on the slit pattern and the reflective layer to minimize the portion where the electrical connection of the connection electrode is broken due to the slit pattern.

Hereinafter, various manufacturing methods of the display device having the slit pattern and the reflective layer described above will be described in more detail with reference to various drawings.

6A to 6L are schematic cross-sectional views illustrating a method of manufacturing a display device according to an exemplary embodiment of the present invention.

Referring to FIG. 6A, after forming the interlayer protective layer 211 on the substrate 210, the pixel electrode 221, the common electrode 222, the first ground electrode 224, and the driving element protective layer 212 are formed. After formation, the light emitting device 250 is disposed using the adhesive layer 213.

The planarization layer 214 is formed to cover the light emitting device 250. When the planarization layer 214 is formed, the planarization layer 214 is patterned so that the common electrode 222 and the pixel electrode 221 are opened, and a connection electrode 230 is formed on the planarization layer.

The connection electrode 230 is formed to be formed on the front surface, but the planarization layer 214 is patterned to be electrically connected to the open common electrode 222 and the pixel electrode 221.

Subsequently, as illustrated in FIG. 6B, a photoresist PR is applied to the front surface to pattern the connection electrode 230. After applying the photoresist (PR), a part of the photoresist (PR) is opened to arrange the slit pattern.

Thereafter, as shown in FIG. 6C, at least a portion of the connection electrode 230 is opened to expose the planarization layer 214. The step of removing at least a portion of the connection electrode 230 is to use a method of wet etching using an etching solution.

Thereafter, as shown in FIG. 6D, the planarization layer 214 is etched to form a slit pattern 240. The width of the slit pattern is 2 to 3 um to be a fine slit. When the open region of the connection electrode 230 mentioned in FIG. 6C is described, the slit pattern 240 is completed by dry etching.

The slit pattern 240 is disposed to surround the light emitting device 250 while being adjacent to the light emitting device 250, but has at least one open area so that the connection electrode 230 is not shorted, that is, a partially cut slit pattern 240 ). The connection electrode 230 on the partially slit pattern 240 is preserved without losing electrical connectivity.

In order to make the width of the slit pattern 240 as described above to have a fine shape of 2 to 3 um, it is difficult to precisely form the etching method using a general photoresist (PR). As described above, the connection electrode 230 is partially opened through wet etching, followed by dry etching to form a slit pattern 240 having a fine width.

In general, dry etching or photoresist (PR) is partly etched, which makes it difficult to form a precise pattern, but when dry etching is performed while the connection electrode is partially opened by wet etching, not only the photoresistor (PR) but also the connection electrode Since it itself performs the role of a mask, it is possible to form a slit pattern 240 having a fine width.

Thereafter, as illustrated in FIGS. 6E to 6G, the photoresist PR is removed, and the photoresist PR is patterned again to apply the entire photoresist PR again and then pattern the connection electrode 230. The connection electrode 230 is wet-etched and patterned to be divided into a first connection electrode 231 and a second connection electrode 232.

Thereafter, as shown in FIGS. 6H to 6L, the photoresist (PR) is removed, the reflective layer is deposited on the front side, and then the photoresist (PR) is deposited and patterned to leave only the reflective layer 260 inside the slit pattern 240. By removing, the slit pattern 240 including the reflective layer 260 may be disposed in a minute shape while adjoining the light emitting device 250.

7A to 7K are schematic cross-sectional views illustrating a method of manufacturing a display device according to another exemplary embodiment of the present invention.

Hereinafter, according to another embodiment of the present invention, in arranging the slit pattern including the reflective layer around the light emitting device, the arrangement of the connecting electrode on the top of the slit pattern to minimize a short circuit of the connecting electrode, etc. Let's explain.

7 is a schematic diagram illustrating a display device according to another embodiment of the present invention.

Referring to FIG. 7, as in the case of FIG. 2, the pixel SP includes a circuit portion SP-c and a pixel portion SP-p. Description will be given with reference to FIG. 7, but a description that is substantially the same as or similar to the element shown in FIG. 2 will be omitted.

A slit pattern 240 adjacent to the light emitting device 250 is disposed around the light emitting device 250. The slit pattern 240 includes a reflective layer 260 and is disposed to surround the light emitting device 250, so that the light emitting device 250 is disposed. ), the path of light emitted from the light emitting device 250 may be adjusted, and thus the light efficiency of the light emitting device 250 may be increased.

The reflective layer 260 may be a metal layer made of a material that can reflect light, and may be electrically connected to any one of the first electrode E1 or the second electrode E2 for grounding. The connection relationship between the electrodes for grounding will be described in detail in the following drawings.

As described above, the reflective layer 260 is disposed inside the slit pattern 240 but is disposed on any one of the inclined surfaces of the slit pattern 240, and is connected to the first electrode E1 and the second electrode E2 at the same time. There is no danger that the common electrode 222 and the pixel electrode 221 are shorted.

In addition, electric charges induced to be electrically connected to the first electrode E1 or the second electrode E2 naturally escape, and charges accumulate to generate static electricity or to affect the electrical flow of other electrical circuits. It doesn't go crazy.

On the other hand, as in the embodiment shown in FIG. 2, since it does not have an open area, it is possible to further improve light efficiency for light emitted from the light emitting device 250.

8A to 8C, the slit pattern 240 is formed on the planarization layer 214 in the same manner as described with reference to the previous drawings. Similarly, a dry and wet etching process is used, and a slit pattern 240 having a fine width is formed by using the connection electrode 230 as a mask in etching using a photoresistor (PR).

The slit pattern 240 does not have to have the open area described in FIGS. 6A to 6L. That is, in another embodiment of the present invention, the slit pattern 240 having no open area is disposed adjacent to the light emitting device 250 and surrounds the light emitting device 250. As a result, the light efficiency can be further improved.

8D to 8F, a reflective layer 260 is formed inside the slit pattern 240. At this time, it is not necessary to separately pattern the connection electrode 230 with two connection electrodes 231 and 232.

Thereafter, the connection electrode 230 is removed as shown in FIG. 8G. When the connection electrode 230 is removed, at least a portion of the connection electrode 230 connected to the reflective layer 260 is left to form the second ground electrode 233. The second ground electrode 233 will be described later, but will be described later as an electrode for grounding the reflective layer 260.

As illustrated in FIGS. 8H to 8I, the inside of the slit pattern 240 is filled with a planarization layer 214 and further disposed to cover the reflective layer 260. The connection electrode 230 is again disposed on the planarization layer 214 including the additionally disposed planarization layer.

8J to 8K, the connection electrode 230 is patterned to be divided into a first connection electrode 231 and a second connection electrode 232, thereby displaying a reflective layer 260 inside the slit pattern 240. Complete the device.

The second ground electrode 233 should be electrically connected to either the first connection electrode 231 or the second connection electrode 232, which is for grounding the reflective layer 260. However, the second ground electrode 233 that grounds the reflective layer 260 should not be electrically connected to the first connection electrode 231 and the second connection electrode 232 at the same time.

8A to 8K, in another embodiment of the present invention, a slit pattern 240 having a fine width is disposed adjacent to the light emitting device 250 and a reflective layer 260 is disposed inside the slit pattern 240. However, the slit pattern 240 and the reflective layer 260 do not need to arrange an open area, and the first connection electrode 231 and the second connection electrode 232 also have a pixel electrode 221 and a common electrode 222. It can be connected smoothly without being shorted in the electrical connection.

The embodiments of the present invention have been described in more detail with reference to the accompanying drawings, but the present invention is not necessarily limited to these embodiments, and may be variously modified 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, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of protection of the present invention should be interpreted by the claims, and all technical spirits within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

100: display device
150, 250: light emitting element
140, 240: slit pattern
160, 260: reflective layer
121, 221: pixel electrode
122, 222: common electrode
230: connecting electrode

Claims (12)

A driving element and a light emitting element on the substrate;
A planarization layer covering the light emitting element;
A slit pattern in the planarization layer; And
And a reflective layer on an inclined surface of at least one side of the slit pattern,
The slit pattern is a display device arranged to surround the light emitting element. According to claim 1,
The slit pattern includes at least one discontinuous section. According to claim 1,
The light emitting device includes a first electrode and a second electrode,
And a first connection electrode and a second connection electrode connected to the first electrode and the second electrode, respectively. According to claim 3,
The reflective layer is a display device electrically connected to the first connection electrode or the second connection electrode. According to claim 1,
And a reflective electrode between the substrate and the light emitting element. According to claim 1,
The inside of the slit pattern is a display device filled with the same material as the planarization layer. A driving element and a light emitting element on the substrate;
A planarization layer covering the light emitting element; And
And a reflective layer inserted in the planarization layer,
The angle between the substrate and the reflective layer is 70 degrees or more. Disposing a driving element and a light emitting element on the substrate;
Disposing a planarization layer and a connection electrode covering the light emitting element;
Forming a slit pattern in the planarization layer around the light emitting element; And
And forming a reflective layer inside the slit pattern. The method of claim 8,
The step of forming a slit pattern in the planarization layer around the light emitting element,
A method of manufacturing a display device further comprising removing at least a part of the connection electrode to arrange the slit pattern. The method of claim 9,
After the step of forming a slit pattern on the planarization layer around the light emitting element
A method of manufacturing a display device further comprising the step of patterning a connection electrode into a first connection electrode and a second connection electrode. The method of claim 8,
After the step of forming a reflective layer inside the slit pattern
Removing the connecting electrode and filling the inside of the slit pattern with a planarization layer; And
And disposing the connection electrode on the planarization layer again. The method of claim 11,
The step of disposing the connection electrode on the planarization layer is
A method of manufacturing a display device comprising the step of patterning a connection electrode into a first connection electrode and a second connection electrode.

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