KR20190018926A - Display device using semiconductor light emitting device - Google Patents

Abstract

The present invention relates to a display device and, specifically, to a display device using a semiconductor light emitting element. According to the present invention, the display device is a display device wherein light is emitted from both sides. According to the present invention, the display device comprises: a base substrate having a first surface and a second surface opposite to each other; a first color conversion part disposed on the first surface of the base substrate to convert a color; a second color conversion part disposed on the second surface of the base substrate to convert a color; and semiconductor light emitting elements disposed between the first surface of the base substrate and the first color conversion part. In detail, the base substrate is provided with a through hole through which light emitted from the semiconductor light emitting elements passes. The through holes may include a filter for filtering light converted by the first and the second color conversion part to prevent the colors from mixing.

Description

Technical Field [0001] The present invention relates to a display device using a semiconductor light-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly, to a double-sided light source device using a semiconductor light emitting device.

In recent years, display devices having excellent characteristics such as a thin shape and a flexible shape in the field of display technology have been developed. On the other hand, major displays that are commercialized today are represented by LCD (Liguid Crystal Display) and AMOLED (Active Matrix Organic Light Emitting Diodes).

However, in the case of an LCD, there is a problem that the reaction time is not fast and the implementation of the flexible is difficult. In the case of the AMOLED, there is a weak point that the life span is short and the mass production yield is not good.

Light emitting diodes (LEDs) are well-known semiconductor light emitting devices that convert current into light. In 1962, red LEDs using GaAsP compound semiconductors were commercialized, Has been used as a light source for a display image of an electronic device including a communication device. Accordingly, a method of solving the above problems by implementing a display using the semiconductor light emitting device can be presented.

The semiconductor light emitting device can be utilized as a small-sized lighting, an automobile lighting, an indoor lighting, and can be utilized as a light source such as an outdoor signboard and an outdoor lighting. Therefore, in a display device including the semiconductor light emitting device, it may be required to emit a light source on both sides.

As described above, the double-sided light source display device including the semiconductor light emitting device has a complicated structure, and the number of the semiconductor light emitting devices used in the construction of the display device increases because the semiconductor light emitting devices are disposed on both sides. Therefore, there is a problem that the manufacturing cost is increased. Accordingly, the present invention provides a display device structure capable of reducing manufacturing costs while implementing a double-sided light source display device.

It is an object of the present invention to provide a double-sided light source display device capable of reducing manufacturing costs.

Another object of the present invention is to provide different colors in different aspects in a double-sided light source display device.

A display device according to the present invention includes a base substrate having a first surface and a second surface opposite to each other, and a first color conversion unit disposed on a first surface of the base substrate to convert color. A second color conversion unit is disposed on a second surface of the base substrate to convert hue, and semiconductor light emitting devices are disposed between the first surface of the base substrate and the first hue conversion unit. In detail, the base substrate is provided with a through hole through which the light emitted from the semiconductor light emitting devices passes, and the through hole is provided with a filter for filtering the light converted by the first and second color conversion units .

In an embodiment, at least a part of the light emitted from the semiconductor light emitting devices is formed to be emitted to the first color light source by being irradiated to the first color conversion unit. At least another portion of the light emitted from the semiconductor light emitting devices passes through the through hole and the filter and is irradiated to the second color conversion unit to be emitted to the light source of the second color.

The first color conversion unit may further include a first phosphor for converting light emitted from the semiconductor light emitting device into the first color and a color purity enhancement layer stacked on the first phosphor.

The second color conversion unit may further include a second phosphor for converting the light emitted from the semiconductor light emitting device into the second color, and a color purity enhancement layer stacked on the second phosphor.

In an exemplary embodiment, the first and second color conversion units include different phosphors to convert light emitted from the semiconductor light emitting devices into different colors.

In an embodiment, the through holes are formed between the semiconductor light emitting elements.

In an embodiment, a gap is disposed between the first surface of the base substrate and the first color conversion portion, and a gap is disposed between the second surface of the base substrate and the second color conversion portion.

In one embodiment of the present invention, the base substrate includes an insulating substrate having a first surface and a second surface opposite to each other, a metal layer formed to cover the first surface and the second surface of the insulating substrate, And a reflective layer stacked on top of each other. Further, the reflective layer is made of metal.

In the display device according to the present invention, the number of semiconductor light emitting devices consumed for realizing the double-sided light source display device may be reduced because the semiconductor light emitting device is disposed between the base substrate and the first color converting unit. Accordingly, a display device with reduced manufacturing cost can be provided.

In addition, according to the present invention, the first and second color conversion units for converting the color of light may be disposed on both sides of the display device, and light may be emitted in different colors on different surfaces.

1 is a conceptual diagram showing an embodiment of a display device using the semiconductor light emitting element of the present invention.
Fig. 2 is a partially enlarged view of part A of Fig. 1, and Figs. 3a and 3b are cross-sectional views taken along line BB and CC of Fig.
4 is a conceptual diagram showing a flip chip type semiconductor light emitting device of FIG.
FIGS. 5A to 5C are conceptual diagrams showing various forms of implementing a color in relation to a flip chip type semiconductor light emitting device.
6 is a cross-sectional view illustrating a method of manufacturing a display device using the semiconductor light emitting device of the present invention.
7 is a perspective view showing another embodiment of a display device using the semiconductor light emitting device of the present invention.
8 is a cross-sectional view taken along line DD of FIG.
9 is a conceptual diagram showing a vertical semiconductor light emitting device of FIG.
Fig. 10 is an enlarged view of a portion A in Fig. 1 for explaining a display device according to another embodiment of the present invention.
11 is a cross-sectional view taken along line EE in Fig.
12 is a cross-sectional view of a display device for explaining another embodiment of the present invention.
13 is a cross-sectional view of a display device for explaining another embodiment of the present invention.
14 is a cross-sectional view of a display device for explaining another embodiment of the present invention.
Fig. 15 is an enlarged view of a portion A of Fig. 1 for explaining a display device according to another embodiment of the present invention. Fig.
16 is a cross-sectional view taken along line FF of Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. In addition, it should be noted that the attached drawings are only for easy understanding of the embodiments disclosed in the present specification, and should not be construed as limiting the technical idea disclosed in the present specification by the attached drawings.

It is also to be understood that when an element such as a layer, region or substrate is referred to as being present on another element "on," it is understood that it may be directly on the other element or there may be an intermediate element in between There will be.

The display device described in this specification includes a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a slate PC, , A Tablet PC, an Ultra Book, a digital TV, a desktop computer, and the like. However, it will be readily apparent to those skilled in the art that the configuration according to the embodiments described herein may be applied to a device capable of being displayed, even in the form of a new product to be developed in the future.

1 is a conceptual diagram showing an embodiment of a display device using the semiconductor light emitting device of the present invention.

According to the illustrated example, the information processed in the control unit of the display device 100 may be displayed using a flexible display.

The flexible display includes a display that can be bent, twistable, collapsible, and curlable, which can be bent by an external force. For example, a flexible display can be a display made on a thin, flexible substrate that can be bent, bent, folded or rolled like paper while maintaining the display characteristics of conventional flat panel displays.

In a state where the flexible display is not bent (for example, a state having an infinite radius of curvature, hereinafter referred to as a first state), the display area of the flexible display is flat. In the first state, the display area may be a curved surface in a state of being bent by an external force (for example, a state having a finite radius of curvature, hereinafter referred to as a second state). As shown in the figure, the information displayed in the second state may be time information output on the curved surface. Such visual information is realized by independently controlling the emission of a sub-pixel arranged in a matrix form. The unit pixel means a minimum unit for implementing one color.

The unit pixel of the flexible display may be implemented by a semiconductor light emitting device. In the present invention, a light emitting diode (LED) is exemplified as one type of semiconductor light emitting device for converting a current into light. The light emitting diode is formed in a small size, so that it can serve as a unit pixel even in the second state.

Hereinafter, a flexible display implemented using the light emitting diode will be described in detail with reference to the drawings.

FIG. 2 is a partial enlarged view of a portion A of FIG. 1, FIGS. 3 A and 3B are cross-sectional views taken along lines BB and CC of FIG. 2, FIG. 4 is a conceptual view of a flip chip type semiconductor light emitting device of FIG. FIGS. 5A to 5C are conceptual diagrams showing various forms of implementing a color in relation to a flip chip type semiconductor light emitting device.

Referring to FIGS. 2, 3A and 3B, a display device 100 using a passive matrix (PM) semiconductor light emitting device as a display device 100 using a semiconductor light emitting device is illustrated. However, the example described below is also applicable to an active matrix (AM) semiconductor light emitting device.

The display device 100 includes a substrate 110, a first electrode 120, a conductive adhesive layer 130, a second electrode 140, and a plurality of semiconductor light emitting devices 150.

The substrate 110 may be a flexible substrate. For example, to implement a flexible display device, the substrate 110 may comprise glass or polyimide (PI). In addition, any insulating material such as PEN (polyethylene naphthalate) and PET (polyethylene terephthalate) may be used as long as it is insulating and flexible. In addition, the substrate 110 may be either a transparent material or an opaque material.

The substrate 110 may be a wiring substrate on which the first electrode 120 is disposed, so that the first electrode 120 may be positioned on the substrate 110.

The insulating layer 160 may be disposed on the substrate 110 on which the first electrode 120 is located and the auxiliary electrode 170 may be disposed on the insulating layer 160. In this case, a state in which the insulating layer 160 is laminated on the substrate 110 may be one wiring substrate. More specifically, the insulating layer 160 is formed of a flexible material such as polyimide (PI), polyimide (PET), or PEN, and is integrally formed with the substrate 110 to form a single substrate.

The auxiliary electrode 170 is an electrode that electrically connects the first electrode 120 and the semiconductor light emitting device 150 and is disposed on the insulating layer 160 and corresponds to the position of the first electrode 120. For example, the auxiliary electrode 170 may be in the form of a dot and may be electrically connected to the first electrode 120 by an electrode hole 171 passing through the insulating layer 160. The electrode hole 171 may be formed by filling a via hole with a conductive material.

Referring to these drawings, the conductive adhesive layer 130 is formed on one surface of the insulating layer 160, but the present invention is not limited thereto. For example, a layer having a specific function may be formed between the insulating layer 160 and the conductive adhesive layer 130, or a structure in which the conductive adhesive layer 130 is disposed on the substrate 110 without the insulating layer 160 It is also possible. In the structure in which the conductive adhesive layer 130 is disposed on the substrate 110, the conductive adhesive layer 130 may serve as an insulating layer.

The conductive adhesive layer 130 may be a layer having adhesiveness and conductivity. To this end, the conductive adhesive layer 130 may be mixed with a substance having conductivity and a substance having adhesiveness. Also, the conductive adhesive layer 130 has ductility, thereby enabling the flexible function in the display device.

As an example, the conductive adhesive layer 130 may be an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing conductive particles, or the like. The conductive adhesive layer 130 may be formed as a layer having electrical insulation in the horizontal X-Y direction while permitting electrical interconnection in the Z direction passing through the thickness. Accordingly, the conductive adhesive layer 130 may be referred to as a Z-axis conductive layer (hereinafter, referred to as a conductive adhesive layer).

The anisotropic conductive film is a film in which an anisotropic conductive medium is mixed with an insulating base member. When heat and pressure are applied, only a specific part of the anisotropic conductive film has conductivity due to the anisotropic conductive medium. Hereinafter, the anisotropic conductive film is described as being subjected to heat and pressure, but other methods may be used to partially conduct the anisotropic conductive film. In this method, for example, either the heat or the pressure may be applied, or UV curing may be performed.

In addition, the anisotropic conduction medium can be, for example, a conductive ball or a conductive particle. According to the example, in the present example, the anisotropic conductive film is a film in which conductive balls are mixed with an insulating base member. When heat and pressure are applied, only specific portions are conductive by the conductive balls. The anisotropic conductive film may be a state in which a plurality of particles coated with an insulating film made of a polymer material are contained in the core of the conductive material. In this case, the insulating film is broken by heat and pressure, . At this time, the shape of the core may be deformed to form a layer in contact with each other in the thickness direction of the film. As a more specific example, heat and pressure are applied to the anisotropic conductive film as a whole, and the electrical connection in the Z-axis direction is partially formed by the height difference of the mating member adhered by the anisotropic conductive film.

As another example, the anisotropic conductive film may be in a state in which a plurality of particles coated with a conductive material are contained in the insulating core. In this case, the conductive material is deformed (pressed) to the portion where the heat and the pressure are applied, so that the conductive material becomes conductive in the thickness direction of the film. As another example, it is possible that the conductive material penetrates the insulating base member in the Z-axis direction and has conductivity in the thickness direction of the film. In this case, the conductive material may have a pointed end.

According to the present invention, the anisotropic conductive film may be a fixed array anisotropic conductive film (ACF) in which conductive balls are inserted into one surface of an insulating base member. More specifically, the insulating base member is formed of a material having adhesiveness, and the conductive ball is concentrated on the bottom portion of the insulating base member, and is deformed together with the conductive ball when heat and pressure are applied to the base member So that they have conductivity in the vertical direction.

However, the present invention is not limited thereto. The anisotropic conductive film may be formed by randomly mixing conductive balls into an insulating base member or by forming a plurality of layers in which a conductive ball is placed in a double- ACF) are all available.

The anisotropic conductive paste is a combination of a paste and a conductive ball, and may be a paste in which a conductive ball is mixed with an insulating and adhesive base material. In addition, solutions containing conductive particles can be solutions in the form of conductive particles or nanoparticles.

Referring again to FIG. 5, the second electrode 140 is located in the insulating layer 160, away from the auxiliary electrode 170. That is, the conductive adhesive layer 130 is disposed on the insulating layer 160 on which the auxiliary electrode 170 and the second electrode 140 are disposed.

After the conductive adhesive layer 130 is formed in a state where the auxiliary electrode 170 and the second electrode 140 are positioned in the insulating layer 160, the semiconductor light emitting device 150 is connected to the semiconductor light emitting device 150 in a flip chip form The semiconductor light emitting device 150 is electrically connected to the first electrode 120 and the second electrode 140.

Referring to FIG. 4, the semiconductor light emitting device may be a flip chip type light emitting device.

For example, the semiconductor light emitting device includes a p-type semiconductor layer 155 in which a p-type electrode 156, a p-type electrode 156 are formed, an active layer 154 formed on the p-type semiconductor layer 155, And an n-type electrode 152 disposed on the n-type semiconductor layer 153 and the p-type electrode 156 on the n-type semiconductor layer 153 and 154 in the horizontal direction. In this case, the p-type electrode 156 may be electrically connected to the auxiliary electrode 170 by the conductive adhesive layer 130, and the n-type electrode 152 may be electrically connected to the second electrode 140.

Referring again to FIGS. 2, 3A and 3B, the auxiliary electrode 170 is elongated in one direction, and one auxiliary electrode may be electrically connected to the plurality of semiconductor light emitting devices 150. For example, the p-type electrodes of the right and left semiconductor light emitting elements may be electrically connected to one auxiliary electrode around the auxiliary electrode.

More specifically, the semiconductor light emitting device 150 is inserted into the conductive adhesive layer 130 by heat and pressure, and the semiconductor light emitting device 150 is inserted into the conductive adhesive layer 130 through the p- And only the portion between the n-type electrode 152 and the second electrode 140 of the semiconductor light emitting device 150 has conductivity and the semiconductor light emitting device does not have a conductive property because the semiconductor light emitting device is not press- The conductive adhesive layer 130 not only couples the semiconductor light emitting device 150 and the auxiliary electrode 170 and the semiconductor light emitting device 150 and the second electrode 140 but also forms an electrical connection.

In addition, the plurality of semiconductor light emitting devices 150 constitute a light emitting element array, and the phosphor layer 180 is formed in the light emitting element array.

The light emitting element array may include a plurality of semiconductor light emitting elements having different brightness values. Each of the semiconductor light emitting devices 150 constitutes a unit pixel and is electrically connected to the first electrode 120. For example, the first electrodes 120 may be a plurality of semiconductor light emitting devices, and the semiconductor light emitting devices may be electrically connected to any one of the plurality of first electrodes.

Also, since the semiconductor light emitting devices are connected in a flip chip form, the semiconductor light emitting devices grown on the transparent dielectric substrate can be used. The semiconductor light emitting devices may be, for example, a nitride semiconductor light emitting device. Since the semiconductor light emitting device 150 has excellent brightness, individual unit pixels can be formed with a small size.

According to the structure, the barrier ribs 190 may be formed between the semiconductor light emitting devices 150. In this case, the barrier ribs 190 may separate the individual unit pixels from each other, and may be integrally formed with the conductive adhesive layer 130. For example, by inserting the semiconductor light emitting device 150 into the anisotropic conductive film, the base member of the anisotropic conductive film can form the partition.

Also, if the base member of the anisotropic conductive film is black, the barrier 190 may have a reflection characteristic and a contrast may be increased without a separate black insulator.

As another example, the barrier ribs 190 may be provided separately from the reflective barrier ribs. In this case, the barrier rib 190 may include a black or white insulation depending on the purpose of the display device. When a barrier of a white insulator is used, an effect of enhancing reflectivity may be obtained. When a barrier of a black insulator is used, a contrast characteristic may be increased while having a reflection characteristic.

The phosphor layer 180 may be located on the outer surface of the semiconductor light emitting device 150. For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device that emits blue (B) light, and the phosphor layer 180 converts the blue (B) light into the color of a unit pixel. The phosphor layer 180 may be a red phosphor 181 or a green phosphor 182 constituting an individual pixel.

That is, a red phosphor 181 capable of converting blue light into red (R) light can be laminated on the blue semiconductor light emitting element 151 at a position forming a red unit pixel, A green phosphor 182 capable of converting blue light into green (G) light may be laminated on the blue semiconductor light emitting element 151. [ In addition, only the blue semiconductor light emitting element 151 can be used alone in a portion constituting a blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) can form one pixel. More specifically, phosphors of one color may be stacked along each line of the first electrode 120. Accordingly, one line in the first electrode 120 may be an electrode for controlling one color. In other words, red (R), green (G), and blue (B) may be arranged in order along the second electrode 140, thereby realizing a unit pixel.

(R), green (G), and blue (B) unit pixels may be implemented by combining the semiconductor light emitting device 150 and the quantum dot QD instead of the fluorescent material. have.

In addition, a black matrix 191 may be disposed between each of the phosphor layers to improve contrast. That is, the black matrix 191 can improve the contrast of light and dark.

However, the present invention is not limited thereto, and other structures for implementing blue, red, and green may be applied.

5A, each of the semiconductor light emitting devices 150 includes gallium nitride (GaN), indium (In) and / or aluminum (Al) are added together to form a high output light Device.

In this case, the semiconductor light emitting device 150 may be a red, green, and blue semiconductor light emitting device to form a unit pixel (sub-pixel), respectively. For example, red, green, and blue semiconductor light emitting elements R, G, and B are alternately arranged, and red, green, and blue unit pixels Form a single pixel, through which a full color display can be implemented.

Referring to FIG. 5B, the semiconductor light emitting device may include a white light emitting device W having a yellow phosphor layer for each individual device. In this case, a red phosphor layer 181, a green phosphor layer 182, and a blue phosphor layer 183 may be provided on the white light emitting element W to form a unit pixel. Further, a unit pixel can be formed by using a color filter in which red, green, and blue are repeated on the white light emitting element W.

Referring to FIG. 5C, a red phosphor layer 181, a green phosphor layer 182, and a blue phosphor layer 183 may be provided on the ultraviolet light emitting element UV. As described above, the semiconductor light emitting device can be used not only for visible light but also for ultraviolet (UV), and can be extended to a form of a semiconductor light emitting device in which ultraviolet (UV) can be used as an excitation source of the upper phosphor .

The semiconductor light emitting device 150 is disposed on the conductive adhesive layer 130 and constitutes a unit pixel in the display device. Since the semiconductor light emitting device 150 has excellent brightness, individual unit pixels can be formed with a small size. The size of the individual semiconductor light emitting device 150 may be 80 mu m or less on one side and may be a rectangular or square device. In the case of a rectangle, the size may be 20 X 80 μm or less.

Also, even if a square semiconductor light emitting device 150 having a length of 10 m on one side is used as a unit pixel, sufficient brightness for forming a display device appears. Accordingly, when the unit pixel is a rectangular pixel having a side of 600 mu m and the other side of 300 mu m as an example, the distance of the semiconductor light emitting element becomes relatively large. Accordingly, in such a case, it becomes possible to implement a flexible display device having HD picture quality.

The display device using the semiconductor light emitting device described above can be manufactured by a novel manufacturing method. Hereinafter, the manufacturing method will be described with reference to FIG.

6 is a cross-sectional view illustrating a method of manufacturing a display device using the semiconductor light emitting device of the present invention.

The conductive adhesive layer 130 is formed on the insulating layer 160 on which the auxiliary electrode 170 and the second electrode 140 are disposed. A first electrode 120, an auxiliary electrode 170, and a second electrode 140 are formed on the wiring substrate, and the insulating layer 160 is formed on the first substrate 110 to form a single substrate (or a wiring substrate) . In this case, the first electrode 120 and the second electrode 140 may be arranged in mutually orthogonal directions. In addition, the first substrate 110 and the insulating layer 160 may include glass or polyimide (PI), respectively, in order to implement a flexible display device.

The conductive adhesive layer 130 may be formed, for example, by an anisotropic conductive film, and an anisotropic conductive film may be applied to the substrate on which the insulating layer 160 is disposed.

A second substrate 112 corresponding to the positions of the auxiliary electrode 170 and the second electrodes 140 and having a plurality of semiconductor light emitting elements 150 constituting individual pixels is disposed on the semiconductor light emitting element 150 Are arranged so as to face the auxiliary electrode 170 and the second electrode 140.

In this case, the second substrate 112 is a growth substrate for growing the semiconductor light emitting device 150, and may be a spire substrate or a silicon substrate.

When the semiconductor light emitting device is formed in units of wafers, the semiconductor light emitting device can be effectively used in a display device by having an interval and a size at which a display device can be formed.

Then, the wiring substrate and the second substrate 112 are thermally bonded. For example, the wiring board and the second substrate 112 may be thermocompression-bonded using an ACF press head. The wiring substrate and the second substrate 112 are bonded by the thermocompression bonding. Only the portion between the semiconductor light emitting device 150 and the auxiliary electrode 170 and the second electrode 140 has conductivity due to the characteristics of the anisotropic conductive film having conductivity by thermocompression, The device 150 may be electrically connected. At this time, the semiconductor light emitting device 150 is inserted into the anisotropic conductive film, and partition walls may be formed between the semiconductor light emitting devices 150.

Then, the second substrate 112 is removed. For example, the second substrate 112 may be removed using a laser lift-off method (LLO) or a chemical lift-off method (CLO).

Finally, the second substrate 112 is removed to expose the semiconductor light emitting devices 150 to the outside. If necessary, a transparent insulating layer (not shown) may be formed by coating a wiring substrate on which the semiconductor light emitting device 150 is coupled with silicon oxide (SiOx) or the like.

Further, the method may further include forming a phosphor layer on one surface of the semiconductor light emitting device 150. For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device that emits blue (B) light, and a red phosphor or a green phosphor for converting the blue (B) A layer can be formed on one surface of the device.

The manufacturing method and structure of the display device using the semiconductor light emitting device described above can be modified into various forms. For example, a vertical semiconductor light emitting device may be applied to the display device described above. Hereinafter, the vertical structure will be described with reference to Figs. 5 and 6. Fig.

In the modifications or embodiments described below, the same or similar reference numerals are given to the same or similar components as those of the previous example, and the description is replaced with the first explanation.

8 is a cross-sectional view taken along the line DD of FIG. 7, and FIG. 9 is a conceptual view illustrating a vertical semiconductor light emitting device of FIG. 8. FIG. 7 is a perspective view showing another embodiment of a display device using the semiconductor light emitting device of the present invention, to be.

Referring to these drawings, the display device may be a display device using a passive matrix (PM) vertical semiconductor light emitting device.

The display device includes a substrate 210, a first electrode 220, a conductive adhesive layer 230, a second electrode 240, and a plurality of semiconductor light emitting devices 250.

The substrate 210 is a wiring substrate on which the first electrode 220 is disposed. The substrate 210 may include polyimide (PI) to implement a flexible display device. In addition, any insulating and flexible material may be used.

The first electrode 220 is disposed on the substrate 210 and may be formed as a long bar electrode in one direction. The first electrode 220 may serve as a data electrode.

A conductive adhesive layer 230 is formed on the substrate 210 on which the first electrode 220 is located. The conductive adhesive layer 230 may be formed of an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing a conductive particle, or the like, as in a display device using a flip chip type light emitting device. ) And the like. However, the present embodiment also exemplifies the case where the conductive adhesive layer 230 is realized by the anisotropic conductive film.

If the semiconductor light emitting device 250 is connected to the semiconductor light emitting device 250 by applying heat and pressure after the anisotropic conductive film is positioned in a state where the first electrode 220 is positioned on the substrate 210, And is electrically connected to the electrode 220. In this case, the semiconductor light emitting device 250 may be disposed on the first electrode 220.

As described above, the electrical connection is generated because heat and pressure are applied to the anisotropic conductive film to partially conduct in the thickness direction. Therefore, in the anisotropic conductive film, it is divided into a portion 231 having conductivity in the thickness direction and a portion 232 having no conductivity.

In addition, since the anisotropic conductive film contains an adhesive component, the conductive adhesive layer 230 realizes electrical connection as well as mechanical bonding between the semiconductor light emitting element 250 and the first electrode 220.

Thus, the semiconductor light emitting device 250 is positioned on the conductive adhesive layer 230, thereby forming individual pixels in the display device. Since the semiconductor light emitting device 250 has excellent brightness, individual unit pixels can be formed with a small size. The size of the individual semiconductor light emitting device 250 may be 80 μm or less on one side and may be a rectangular or square device. In the case of a rectangle, the size may be 20 X 80 μm or less.

The semiconductor light emitting device 250 may have a vertical structure.

A plurality of second electrodes 240 electrically connected to the vertical semiconductor light emitting device 250 are disposed between the vertical semiconductor light emitting devices in a direction crossing the longitudinal direction of the first electrode 220.

9, the vertical type semiconductor light emitting device includes a p-type electrode 256, a p-type semiconductor layer 255 formed on the p-type electrode 256, an active layer 254 formed on the p-type semiconductor layer 255 An n-type semiconductor layer 253 formed on the active layer 254 and an n-type electrode 252 formed on the n-type semiconductor layer 253. In this case, the p-type electrode 256 located at the bottom may be electrically connected to the first electrode 220 by the conductive adhesive layer 230, and the n-type electrode 252 located at the top may be electrically connected to the second electrode 240 As shown in FIG. Since the vertical semiconductor light emitting device 250 can arrange the electrodes up and down, it has a great advantage that the chip size can be reduced.

Referring to FIG. 8 again, a phosphor layer 280 may be formed on one side of the semiconductor light emitting device 250. For example, the semiconductor light emitting device 250 is a blue semiconductor light emitting device 251 that emits blue (B) light, and a phosphor layer 280 for converting the blue (B) . In this case, the phosphor layer 280 may be a red phosphor 281 and a green phosphor 282 constituting individual pixels.

That is, a red phosphor 281 capable of converting blue light into red (R) light can be laminated on the blue semiconductor light emitting element 251 at a position forming a red unit pixel, A green phosphor 282 capable of converting blue light into green (G) light may be laminated on the blue semiconductor light emitting element 251. In addition, only the blue semiconductor light emitting element 251 can be used alone in a portion constituting a blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) can form one pixel.

However, the present invention is not limited thereto, and other structures for implementing blue, red, and green may be applied to a display device to which a flip chip type light emitting device is applied, as described above.

The second electrode 240 is located between the semiconductor light emitting devices 250 and electrically connected to the semiconductor light emitting devices 250. For example, the semiconductor light emitting devices 250 may be disposed in a plurality of rows, and the second electrode 240 may be disposed between the columns of the semiconductor light emitting devices 250.

The second electrode 240 may be positioned between the semiconductor light emitting devices 250 because the distance between the semiconductor light emitting devices 250 forming the individual pixels is sufficiently large.

The second electrode 240 may be formed as a long bar-shaped electrode in one direction and may be disposed in a direction perpendicular to the first electrode.

The second electrode 240 and the semiconductor light emitting device 250 may be electrically connected by a connection electrode protruding from the second electrode 240. More specifically, the connection electrode may be an n-type electrode of the semiconductor light emitting device 250. For example, the n-type electrode is formed as an ohmic electrode for ohmic contact, and the second electrode covers at least a part of the ohmic electrode by printing or vapor deposition. Accordingly, the second electrode 240 and the n-type electrode of the semiconductor light emitting device 250 can be electrically connected.

According to the example, the second electrode 240 may be disposed on the conductive adhesive layer 230. A transparent insulating layer (not shown) containing silicon oxide (SiOx) or the like may be formed on the substrate 210 on which the semiconductor light emitting device 250 is formed. When the second electrode 240 is positioned after the transparent insulating layer is formed, the second electrode 240 is positioned on the transparent insulating layer. In addition, the second electrode 240 may be formed spaced apart from the conductive adhesive layer 230 or the transparent insulating layer.

If a transparent electrode such as ITO (Indium Tin Oxide) is used for positioning the second electrode 240 on the semiconductor light emitting device 250, the problem that the ITO material has poor adhesion with the n-type semiconductor layer have. Accordingly, the present invention has an advantage in that the second electrode 240 is positioned between the semiconductor light emitting devices 250, so that a transparent electrode such as ITO is not used. Therefore, the light extraction efficiency can be improved by using a conductive material having good adhesiveness with the n-type semiconductor layer as a horizontal electrode without being bound by transparent material selection.

According to the structure, the barrier ribs 290 may be positioned between the semiconductor light emitting devices 250. That is, the barrier ribs 290 may be disposed between the vertical semiconductor light emitting devices 250 to isolate the semiconductor light emitting devices 250 forming the individual pixels. In this case, the barrier ribs 290 may separate the individual unit pixels from each other, and may be formed integrally with the conductive adhesive layer 230. For example, by inserting the semiconductor light emitting device 250 into the anisotropic conductive film, the base member of the anisotropic conductive film can form the partition.

Also, if the base member of the anisotropic conductive film is black, the barrier ribs 290 may have a reflection characteristic and a contrast may be increased without a separate black insulator.

As another example, as the partition 190, a reflective barrier may be separately provided. The barrier ribs 290 may include black or white insulators depending on the purpose of the display device.

If the second electrode 240 is directly disposed on the conductive adhesive layer 230 between the semiconductor light emitting devices 250, the barrier ribs 290 may be formed between the vertical semiconductor light emitting device 250 and the second electrode 240 As shown in FIG. Therefore, individual unit pixels can be formed with a small size by using the semiconductor light emitting device 250, and the distance between the semiconductor light emitting device 250 can be relatively large enough so that the second electrode 240 can be electrically connected to the semiconductor light emitting device 250 ), And it is possible to realize a flexible display device having HD picture quality.

In addition, according to the present invention, a black matrix 291 may be disposed between the respective phosphors to improve the contrast. That is, this black matrix 291 can improve the contrast of light and dark.

As described above, the semiconductor light emitting device 250 is disposed on the conductive adhesive layer 230, thereby forming individual pixels in the display device. Since the semiconductor light emitting device 250 has excellent brightness, individual unit pixels can be formed with a small size. Therefore, a full color display in which red (R), green (G), and blue (B) unit pixels form one pixel can be realized by the semiconductor light emitting device.

In the above description, the structure in which the light source is emitted only to one side of the display device has been described. A display device in which a light source is emitted from both sides of a display device may be required as the use of the display device is expanded by a light source such as a miniature lighting, an automobile lighting, an indoor lighting, an outdoor signboard, and an outdoor lighting.

In the present invention, a display device in which a light source is emitted from both sides of a display device is presented. In detail, in the present invention, a display device is provided in which a semiconductor light emitting device is disposed between a base substrate and the first color converting unit, and the number of semiconductor light emitting devices consumed for realizing a two-sided light source display device is reduced, thereby reducing manufacturing costs . In addition, the first and second color conversion units for converting the color of light are respectively disposed on both sides of the display device, and light is emitted in different colors on different surfaces, so that it can be utilized in various application devices.

 Hereinafter, a display device in which a light source is emitted from both sides of a display device including first and second color conversion parts will be described.

Fig. 10 is an enlarged view of a portion A of Fig. 1 for explaining another embodiment of the present invention of a display device of a new structure. 11 is a cross-sectional view taken along the line E-E in Fig.

10 and 11, a display device 1000 applicable as an illumination or light source using a semiconductor light emitting device is illustrated. The present invention can be applied to a display device 1000 using a passive matrix (PM) semiconductor light emitting device or an active matrix (AM) semiconductor light emitting device as an example of a display device 1000 using a semiconductor light emitting device Do.

The display device 1000 includes a base substrate 1010 having a first surface and a second surface opposite to each other, a first color conversion unit 1080 arranged on the first surface of the base substrate 1010 to convert color, A second color conversion unit 1090 disposed on the second surface of the base substrate 1010 to convert color and a second color conversion unit 1040 disposed between the first surface of the base substrate 1010 and the first color conversion unit 1080 And semiconductor light emitting elements 1050.

In addition, the outermost angle of the display device 1000 can be surrounded by the protective film 1001 to be protected from moisture, contamination or impact from the outside. The protective film 1001 can be any material that minimizes the loss of the light source emitted from the display device 1000.

In the embodiment, the base substrate 1010 is formed with a through hole 1014 through which the light emitted from the semiconductor light emitting devices 1050 passes. The through hole 1014 is provided with a filter 1015 for filtering light so that the converted light from the first color converting unit 1080 and the second color converting unit 1090 can be prevented from being mixed.

In detail, the semiconductor light emitting element 1050 may be the vertical semiconductor light emitting element described above. The semiconductor light emitting device 1050 may have a stacked structure of a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer (not shown). More specifically, the first conductive semiconductor layer may be a p-type semiconductor layer, and the second conductive semiconductor layer may be an n-type semiconductor layer. However, the present invention is not limited thereto, and the first conductivity type may be n-type and the second conductivity type may be p-type.

Each semiconductor light emitting element 1050 constitutes a unit pixel and is electrically connected to the first electrode 1020. For example, the first electrode 1020 may be a plurality of semiconductor light emitting devices 1050, and the semiconductor light emitting devices of each column may be electrically connected to any one of the plurality of first electrodes .

In one embodiment, the first electrode 1020 is disposed between the semiconductor light emitting device 1050 and the base substrate 1010 and is formed in a line shape below the semiconductor light emitting device 1050, 1050, respectively.

Also, in applications such as illumination that emits monochromatic light without the need to alternate red, green, and blue (R, G, B) arrangements, the first electrode 1020 may be formed in the form of a surface electrode . Further, as shown in FIGS. 10 and 11, the first electrode 1020 may be disposed between the base substrates 1010 in a manner corresponding to a lower portion of the semiconductor light emitting device 1050. In such a case, the first electrodes, which are disconnected from each other through the metal layer 1012 and the reflective layer 1013, may be electrically connected to each other.

The second electrode 1040 of the display device 1000 is disposed in a direction opposite to the first electrode 1020 with the semiconductor light emitting element 1050 interposed therebetween and electrically connected to the semiconductor light emitting element 1050 . In detail, the second electrode 1040 may be formed in the form of a line electrode and a surface electrode composed of a transparent electrode, and may be connected to the plurality of semiconductor light emitting devices 1050.

An insulating member 1030 surrounding the semiconductor light emitting device 1050 is provided to prevent direct electrical connection between the first electrode 1020 and the second electrode 1040. In one embodiment, the insulating member 1030 may include polydimethylsiloxane (PDMS) or polymethylphenylsiloxane (PMPS) as a polymeric material. The insulating member 1030 surrounds the semiconductor light emitting device 1050, Material can be included. In addition, the insulating member 1030 may have transparency as a material through which light can pass. Thus, the light emitted from the semiconductor light emitting element 1050 can pass through the through hole 1014, which will be described later.

The semiconductor light emitting device 1050, which receives electrical energy through the first electrode 1020 and the second electrode 1040, may emit light. In detail, at least a part of the light emitted from the semiconductor light emitting device 1050 is irradiated to the first color converting unit 1080 so that the light is emitted to the light source of the first color. .

At least another portion of the light emitted from the semiconductor light emitting device 1050 passes through the through hole 1014 and the filter 1015 and is emitted to the second color conversion unit 1090 to be emitted as the light source of the second color .

The light emitted from the semiconductor light emitting element 1050 and reflected at the interface of the first color conversion portion 1080 may pass through the through hole 1014 and the filter 1015. When the light directly emitted from the semiconductor light emitting element 1050 passes through the through hole 1014 or is reflected at the interface of the first color conversion portion 1080 and passes through the through hole 1014, The light source of the first color does not mix with the light that enters the light source 1014.

However, when light emitted from the semiconductor light emitting element 1050 and passing through a part of the first color conversion portion 1080 is reflected by various factors and passes through the through hole 1014, the light is introduced into the through hole 1014 The light source of the first color may be mixed and introduced into the light. That is, since light mixed with the light source of the first color is emitted to the second color conversion unit 1090, the light to be emitted as the light source of the second color is changed to a color that is not intended by the light source of the first color, .

Accordingly, in order to prevent color mixture of light to be emitted as the light source of the second color, a filter 1015 for filtering the light converted by the first color conversion unit 1080 may be provided. In more detail, the filter 1015 may filter the light source of the first color to transmit the light emitted from the semiconductor light emitting device 1050 to the second color conversion unit 1090. The filter 1015 may be provided in the through hole 1014 and may be formed to cover the through hole 1014 on the second surface of the base substrate 1010 as shown in FIG. In addition, a plurality of filters may be provided to more effectively prevent mixed color of the first color conversion unit 1080 and the second color conversion unit 1090.

The filter 1015 may be provided in the through hole 1014 to prevent color mixture of the first color conversion unit 1080 and the second color conversion unit 1090 of the display device 1000, But may be provided without limitation. The various filters provided in the through holes in the other embodiments of the present invention shown in FIGS. 12 to 14 will be described below.

The first color converter 1080 includes a first phosphor 1081 that converts light emitted from the semiconductor light emitting device 1050 into the first color and a color purity enhancement layer 1082 that is layered on the first phosphor 1081, . For example, the first phosphor 1081 may be formed of a red phosphor that can be converted into red light when the first color is red (R), a green phosphor that can be converted into green light when green (G) As shown in FIG. Further, when the first color is blue (B), the blue phosphor may be formed.

On the other hand, the color purity improving layer 1082 is formed of a color filter having the same hue as the color of light emitted through the first phosphor 1081. Specifically, the color purity enhancement layer 1082 may be formed of a red color filter, a green color filter, and a blue color filter according to the first color. The color purity improving layer 1082 can prevent the external light from being mixed with the light emitted through the first phosphor 1081 to be defective. Since the color purity improving layer 1082 absorbs unnecessary light other than the color of the color purity improving layer 1082, it also has an effect of suppressing reflection of external light.

The second color conversion unit 1090 includes a second phosphor 1091 and a second phosphor 1091 that convert light emitted through the through hole 1014 and the filter 1015 into the second color, And further includes a stacked color purity improving layer 1092. The description of the second phosphor 1091 of the second color converter 1090 may be omitted from the description of the first phosphor 1081 of the first color converter 1080 described above. The description of the color purity improving layer 1092 of the second color converting section 1090 can be replaced with the description of the color purity improving layer 1082 of the first color converting section 1080 described above.

Further, the first and second color conversion units convert light emitted from the semiconductor light emitting devices 1050 into different colors. Accordingly, the first phosphor 1081 and the second phosphor 1091 may include different phosphors. That is, the first and second color conversion units capable of emitting different colors may be disposed on both sides of the display device 1000, and light of different colors may be emitted from different planes .

In one embodiment, a through hole 1014 is formed between the semiconductor light emitting elements 1050. [ The through hole 1014 is formed so that the light emitted from the semiconductor light emitting element 1050 or the light reflected at the interface of the first color conversion portion 1080 passes through the second color conversion portion 1090 so that light can be sufficiently emitted from the second color conversion portion 1090 Can be designed. Accordingly, the through hole 1014 may be formed in the form of a circular column, a quadrangular column, and a polygonal column, and the shape of the through hole 1014 is not limited in the present invention, and may be formed in various forms.

Further, the display device 1000 may be arranged such that a gap 1070 is disposed between the first surface of the base substrate 1010 and the first color conversion portion 1080 so that sufficient light can pass through the through hole 1014 . In detail, the light emitted from the semiconductor light emitting element 1050 or the light reflected at the interface of the first color conversion portion 1080 can pass through the through hole 1014 without loss due to the medium due to the arrangement of the gap 1070 have.

In addition, a gap 1070 'is also provided between the second surface of the base substrate 1010 and the second color conversion portion 1090 in order to sufficiently supply light to the second color conversion portion 1090 through the through hole 1014, Can be arranged. In detail, light passing through the through hole 1014 can be irradiated to the second color conversion portion 1090 without loss by the medium by the gap 1070 '.

More specifically, at least a part of the light passing through the through hole 1014 is irradiated to the second color conversion unit 1090 through the through hole 1014, And is emitted as a light source of a second color. At least another portion of the light passing through the through hole 1014 is reflected at the interface of the second color conversion portion 1090 and reflected to the second surface of the base substrate 1010 through the gap 1070 ' It may be reflected by the second surface of the base substrate 1010 and irradiated to the second color conversion unit 1090. [

Referring to the base substrate 1010 having first and second surfaces opposite to each other, the base substrate 1010 includes an insulating substrate 1011 having a first surface and a second surface opposite to each other, . The first and second surfaces of the insulating substrate 1011 have the same orientation with the first surface and the second surface, respectively. That is, the first surface of the base substrate 1010 and the first surface of the insulating substrate 1011 are in the same direction. The insulating substrate 1011 may include glass or a polymer material. Any insulating material may be used. In order to implement a flexible display device, a flexible material such as polyimide (PI), polyethylene naphthalate (PEN), or polyethylene terephthalate (PET) may be used as the insulating substrate 1011. Further, the insulating substrate 1011 may be either a transparent material or an opaque material.

The base substrate 1010 includes metal layers formed to cover the first and second surfaces of the insulating substrate 1011, respectively. As shown in FIG. 11, the metal layer 1012 may be formed of a plurality of layers, and may include a first metal layer 1012a and a second metal layer 1012b. Further, the metal layer 1012 'may also include a first metal layer 1012a' and a second metal layer 1012b '.

Further, reflection layers 1013 and 1013 'may be stacked on the surfaces of the metal layers 1012 and 1012', respectively. The reflective layer 1013 is formed so that the light emitted from the semiconductor light emitting device 1050 and irradiated to the first color conversion unit 1080 is efficiently transmitted to the first color conversion unit 1080 so that the light efficiency of the display device 1000 Can be improved. In addition, the reflection layer 1013 'may allow the light to be emitted to the second color conversion unit 1090 through the through hole 1014 to be efficiently transmitted to the second color conversion unit 1090.

In one embodiment, when the first electrodes 1020 are disposed to be disconnected from each other, the first electrodes disconnected from each other through the metal layer 1012 and the reflective layer 1013 can be electrically connected to each other. Accordingly, the reflective layer 1013 may be made of a metal and have electrical conductivity. In detail, the reflective layer may be a high reflective material including at least one of aluminum (Al), silver (Ag), and silver-palladium-copper alloy (APC, Ag-Pd-Cu alloy).

Further, in still another embodiment of the present invention to be described below, the same or similar reference numerals are given to the same or similar components as those of the previous example, and the description is replaced with the first explanation.

12 is a cross-sectional view of a display device 1100 for explaining another embodiment of the present invention.

12, a through hole 1114 of the display device 1100 may include a filter 1115 including a first filter 1115a and a second filter 1115b for filtering light. A second filter 1115b may be stacked on the first filter 1115a.

In one embodiment, the first filter 1115a may prevent the light source of the first color from mixing with the light entering the through-hole 1114. [ Further, the second filter 1115b reflects a light source of a second color passing through a part of the second color conversion unit 1190 by various factors and flows in through the through hole 1114 again, 1180 in order to prevent them from affecting the first color emitted.

Therefore, it is possible to prevent the second spike emitted from the second color converter 1190 from being mixed by the first color due to the provision of the first filter 1115a. In addition, the second filter 1115b may prevent the first color emitted from the first color conversion unit 1180 from being mixed with the second color.

13 is a cross-sectional view of a display device 1200 for explaining another embodiment of the present invention.

Referring to FIG. 13, a first filter 1215a and a second filter 1215b for filtering light are disposed in the through-hole 1214 so as to be spaced apart from each other. In detail, the first filter 1215a may be disposed on the first side of the base substrate 1210. [ On the other hand, the second filter 1215b may be disposed on the second side of the base substrate 1210

14 is a sectional view of a display device 1300 for explaining another embodiment of the present invention.

Referring to FIG. 14, a first filter 1315a and a second filter 1315b for filtering light are disposed in the through-hole 1314 so as to be spaced apart from each other. In detail, the first filter 1315a may be inserted into the through hole 1314 and disposed close to the first surface of the base substrate 1310. [ The second filter 1315b may be inserted into the through hole 1314 and disposed close to the second surface of the base substrate 1310. [

Fig. 15 is an enlarged view of a portion A of Fig. 1 for explaining a display device 1400 according to still another embodiment of the present invention, and Fig. 16 is a sectional view taken along F-F of Fig.

15 and 16, a display device 1400 includes a base substrate 1410 having a first surface and a second surface opposite to each other, a first substrate 1410 disposed on the first surface of the base substrate 1410, A second color conversion unit 1090 disposed on the second surface of the base substrate 1410 for converting color and a second color conversion unit 1090 for converting the color of the first surface of the base substrate 1410 and the first color conversion unit 1410, And semiconductor light emitting elements 1450 disposed between the light emitting elements 1480. And further includes semiconductor light emitting elements 1450 'disposed between the second surface of the base substrate 1410 and the second color conversion portion 1490. Thus, the light source can be emitted from both sides of the display device 1400.

The above-described display device using the semiconductor light emitting device is not limited to the configuration and the method of the embodiments described above, but all or a part of the embodiments may be selectively combined so that various modifications may be made to the embodiments It is possible.

Claims (9)

A base substrate having a first surface and a second surface opposite to each other;
A first color conversion unit disposed on a first surface of the base substrate to convert color;
A second color conversion unit disposed on a second surface of the base substrate to convert color; And
And semiconductor light emitting elements disposed between the first surface of the base substrate and the first color conversion portion,
Wherein the base substrate is provided with a through hole through which light emitted from the semiconductor light emitting elements passes,
Wherein the through-hole is provided with a filter for filtering the light converted by the first and second color conversion units. The method according to claim 1,
At least a part of the light emitted from the semiconductor light emitting devices is irradiated to the first color conversion unit to be emitted as a light source of a first color,
Wherein at least another portion of the light emitted from the semiconductor light emitting devices passes through the through hole and the filter and is irradiated to the second color conversion unit to be emitted as a light source of a second color. 3. The method of claim 2,
Wherein the first color conversion unit comprises:
A first phosphor that converts light emitted from the semiconductor light emitting device into the first color; And
And a color purity enhancement layer laminated on the first phosphor. 3. The method of claim 2,
Wherein the second color conversion unit comprises:
A second phosphor for converting light emitted from the semiconductor light emitting device into the second color; And
And a color purity enhancement layer laminated on the second phosphor. 3. The method of claim 2,
Wherein the first and second color conversion units include different phosphors to convert light emitted from the semiconductor light emitting devices into different colors. The method according to claim 1,
And the through holes are formed between the semiconductor light emitting elements. The method according to claim 1,
A gap is disposed between the first surface of the base substrate and the first color conversion unit,
And a gap is disposed between the second surface of the base substrate and the second color conversion unit. The method according to claim 1,
The base substrate includes:
An insulating substrate having a first surface and a second surface opposite to each other;
A metal layer formed to cover the first and second surfaces of the insulating substrate, respectively; And
And a reflective layer laminated on the surface of the metal layer. 9. The method of claim 8,
Wherein the reflective layer is made of metal.

Images