WO2017217703A1

WO2017217703A1 - Display apparatus and manufacturing method thereof

Info

Publication number: WO2017217703A1
Application number: PCT/KR2017/006038
Authority: WO
Inventors: Motonobu Takeya; Young Hyun Kim; Jong Ik Lee
Original assignee: Seoul Semiconductor Co., Ltd
Priority date: 2016-06-13
Filing date: 2017-06-09
Publication date: 2017-12-21
Also published as: US20170358624A1; US10096647B2

Abstract

Disclosed are a display apparatus and a method of manufacturing the same. The display apparatus include: a light emitting diode part including a plurality of light emitting diodes regularly arranged thereon; and a TFT panel part driving the light emitting diode part, wherein the light emitting diode part includes a transparent electrode; the plurality of light emitting diodes regularly arranged on the transparent electrode and electrically connected to the transparent electrode; a plurality of first reflective electrodes disposed at sides of the plurality of light emitting diodes to surround the plurality of light emitting diodes and electrically connected to the transparent electrode; and a plurality of second reflective electrodes electrically connected to the plurality of light emitting diodes, respectively, and reflecting light emitted from the plurality of light emitting diodes.

Description

DISPLAY APPARATUS AND MANUFACTURING METHOD THEREOF

Exemplary embodiments of the present disclosure relate to a display apparatus and a method of manufacturing the same, and more particularly, to a display apparatus using micro-light emitting diodes and a method of manufacturing the same.

A light emitting diode refers to an inorganic semiconductor device that emits light through recombination of electrons and holes and has recently been used in various fields including displays, automobile lamps, general lighting, and the like. Such a light emitting diode has various advantages such as long lifespan, low power consumption, and rapid response. As a result, a light emitting device using a light emitting diode is used as a light source in various fields.

Recently, smart TVs or monitors realize colors using a thin film transistor liquid crystal display (TFT LCD) panel and use light emitting diodes as a light source for a backlight unit for color realization. In addition, a display apparatus is often manufactured using organic light emitting diodes (OLEDs).

In a TFT-LCD, since one LED is used as a light source for many pixels, a backlight light source must be kept in a turned-on state. As a result, the TFT-LCD suffers from constant power consumption regardless of brightness of a displayed screen.

In addition, although power consumption of an OLED display apparatus has been continuously reduced due to the technological development, the OLED still has much higher power consumption than LEDs formed of inorganic semiconductors and thus has low efficiency.

Moreover, a PM drive type OLED display apparatus can suffer from deterioration in response speed upon pulse amplitude modulation (PAM) of the OLED having large capacitance, and can suffer from deterioration in lifespan upon high current driving through pulse width modulation (PWM) for realizing a low duty ratio.

Moreover, an AM driving type OLED display apparatus requires connection of TFTs for each pixel, thereby causing increase in manufacturing costs and non-uniform brightness according to characteristics of TFTs.

Exemplary embodiments of the present disclosure provide a display apparatus using micro-light emitting diodes having low power consumption to be applicable to a wearable apparatus, a smartphone or a TV, and a method of manufacturing the same.

In accordance with one aspect of the present disclosure, a display apparatus includes: a light emitting diode part including a plurality of light emitting diodes regularly arranged thereon; and a TFT panel part driving the light emitting diode part, wherein the light emitting diode part includes a transparent electrode; the plurality of light emitting diodes regularly arranged on the transparent electrode and electrically connected to the transparent electrode; a plurality of first reflective electrodes disposed at sides of the plurality of light emitting diodes to surround the plurality of light emitting diodes and electrically connected to the transparent electrode; and a plurality of second reflective electrodes electrically connected to the plurality of light emitting diodes, respectively, and reflecting light emitted from the plurality of light emitting diodes.

In accordance with another aspect of the present disclosure, a method of manufacturing a display apparatus includes: manufacturing a light emitting diode part including a plurality of light emitting diodes regularly arranged thereon; and coupling the light emitting diode part to a TFT panel part including a plurality of TFTs driving the plurality of light emitting diodes, wherein manufacturing the light emitting diode part includes: arranging the plurality of light emitting diodes on a transparent electrode; forming an encapsulation layer to cover the plurality of light emitting diodes; forming a plurality of mesas by etching the encapsulation layer so as to include one of the plurality of light emitting diodes; forming a first reflective electrode to surround side surfaces of the plurality of mesas; and forming a second reflective electrode to be electrically connected to the plurality of light emitting diodes.

In accordance with a further aspect of the present disclosure, a display apparatus includes: a light emitting part including a plurality of light emitting diodes regularly arranged thereon; and a TFT panel part including a plurality of TFTs driving the plurality of light emitting diodes, wherein the light emitting part includes: a substrate; the plurality of light emitting diodes regularly arranged on the substrate; an encapsulation layer disposed to surround the plurality of light emitting diodes and formed with grooves exposing upper surfaces of the plurality of light emitting diodes; and a transparent electrode disposed on the plurality of light emitting diodes and electrically connected to the plurality of light emitting diodes through the grooves.

According to exemplary embodiments, the display apparatus employs micro-light emitting diodes formed of nitride semiconductors to realize high resolution, low power consumption and high efficiency so as to be applicable to a wearable apparatus.

In addition, the display apparatus according to the exemplary embodiments is configured to allow light emitted from side surfaces of the light emitting diodes to be discharged through reflection by reflective electrodes, thereby enabling reduction in thickness of the light emitting diode part.

According to exemplary embodiments, the display apparatus employs micro-light emitting diodes formed of nitride semiconductors to realize high resolution, low power consumption and high efficiency. Accordingly, the display apparatus is applicable to a variety of apparatus including a wearable apparatus.

In addition, the display apparatus according to the exemplary embodiments is configured to allow light emitted through upper and side surfaces of the light emitting diodes to be discharged outside and to allow light emitted through the side surfaces thereof to be discharged upwards through reflection by a reflective electrode, thereby improving luminous efficacy.

Furthermore, the display apparatus employs light emitted through the side surfaces of the light emitting diodes, thereby enabling reduction in thickness thereof.

Figure 1 is a sectional view of a display apparatus according to a first exemplary embodiment of the present disclosure.

Figure 2 is sectional views illustrating a process of manufacturing light emitting diodes of the display apparatus according to the first exemplary embodiment.

Figure 3 is sectional views illustrating a process of manufacturing a phosphor layer of the display apparatus according to the first exemplary embodiment.

Figure 4 is sectional views illustrating a process of manufacturing a light emitting diode part of the display apparatus according to the first exemplary embodiment.

Figure 5 is sectional views illustrating a process of coupling a TFT panel part to the light emitting diode part of the display apparatus according to the first exemplary embodiment.

Figure 6 is a sectional view of a display apparatus according to a second exemplary embodiment of the present disclosure.

Figure 7 is sectional views illustrating a process of manufacturing a light emitting diode part of the display apparatus according to the second exemplary embodiment.

Figure 8 is sectional views illustrating a process of coupling a TFT panel part to the light emitting diode part of the display apparatus according to the second exemplary embodiment.

Figure 9 is a sectional view of a display apparatus according to a third exemplary embodiment of the present disclosure.

Figure 10 is a sectional view of a display apparatus according to a fourth exemplary embodiment of the present disclosure.

Figure 11 is a sectional view of a display apparatus according to a fifth exemplary embodiment of the present disclosure.

Figure 12 is a sectional view of a display apparatus according to a sixth exemplary embodiment of the present disclosure.

Figure 13 is a sectional view of a display apparatus according to a seventh exemplary embodiment of the present disclosure.

Figure 14 is a sectional view of a display apparatus according to an eighth exemplary embodiment of the present disclosure.

Figure 15 is an enlarged view of part A of Figure 14.

Figure 16 is sectional views illustrating a process of manufacturing light emitting diodes of the display apparatus according to the eighth exemplary embodiment of the present disclosure.

Figure 17 is sectional views illustrating a process of manufacturing a light emitting part of the display apparatus according to the eighth exemplary embodiment.

Figure 18 is a sectional view of a display apparatus according to a ninth exemplary embodiment of the present disclosure.

Each of the plurality of light emitting diodes may include: a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer and an active layer interposed between the first and second conductivity type semiconductor layers; a first electrode disposed to cover the first conductivity type semiconductor layer and electrically connected to the first conductivity type semiconductor layer; and a second electrode disposed to cover the second conductivity type semiconductor layer and electrically connected to the second conductivity type semiconductor layer.

Each of the plurality of light emitting diodes may further include: an insulating layer interposed between the second conductivity type semiconductor layer and the second electrode and formed therein with a through-hole through which the second conductivity type semiconductor layer is exposed, and the second electrode may be electrically connected to the second conductivity type semiconductor layer through the through-hole.

The plurality of second reflective electrodes may be electrically connected to the second electrode.

The light emitting diode part may further include a color filter disposed on the other surface of the transparent electrode having the plurality of light emitting diodes arranged on one surface thereof, and blocking light emitted from the plurality of light emitting diodes and having a certain wavelength.

The color filter may further include: a green light portion allowing only green light to pass therethrough among light emitted from the light emitting diodes; and a red light portion allowing only red light to pass therethrough among light emitted from the light emitting diodes, and may further include a blue light portion allowing only blue light to pass therethrough among light emitted from the light emitting diodes.

The light emitting diodes may be blue light emitting diodes and the light emitting diode part may further include: a transparent encapsulation layer disposed to fill a space between the blue light emitting diode disposed at a location corresponding to the blue light portion and the first reflective electrode and allowing blue light emitted from the blue light emitting diodes to pass therethrough; a green phosphor layer disposed to fill a space between the blue light emitting diode disposed at a location corresponding to the green light portion and the first reflective electrode and converting blue light emitted from the blue light emitting diodes into green light through wavelength conversion; and a red phosphor layer disposed to fill a space between the blue light emitting diode disposed at a location corresponding to the red light portion and the first reflective electrode and converting blue light emitted from the blue light emitting diodes into red light through wavelength conversion.

The light emitting diodes may be UV light emitting diodes and the light emitting diode part may further include: a blue phosphor layer disposed to fill a space between the UV light emitting diode disposed at a location corresponding to the blue light portion and the first reflective electrode and converting UV light emitted from the UV light emitting diodes into blue light through wavelength conversion; a green phosphor layer disposed to fill a space between the UV light emitting diodes disposed at a location corresponding to the green light portion and the first reflective electrode and converting UV light emitted from the UV light emitting diodes into green light through wavelength conversion; and a red phosphor layer disposed to fill a space between the UV light emitting diodes disposed at a location corresponding to the red light portion and the first reflective electrode and converting UV light emitted from the UV light emitting diodes into red light through wavelength conversion.

The light emitting diode part may further include a phosphor layer interposed between the transparent electrode and the color filter and emitting white light through wavelength conversion of light emitted from the plurality of light emitting diodes.

The light emitting diode part may further include a phosphor layer disposed to fill spaces between the plurality of light emitting diodes and the plurality of first reflective electrodes and emitting white light through wavelength conversion of light emitted from the plurality of light emitting diodes.

The light emitting diode part may further include a phosphor layer disposed on the other surface of the transparent electrode having the plurality of light emitting diodes arranged on one surface thereof, and converting wavelengths of light emitted from the plurality of light emitting diodes.

The light emitting diode part may further include a phosphor layer disposed to fill spaces between the plurality of light emitting diodes and the plurality of first reflective electrodes.

The light emitting diodes may be blue light emitting diodes and the phosphor layer may include a green phosphor layer emitting green light through wavelength conversion of blue light emitted from the blue light emitting diodes; a red phosphor layer emitting red light through wavelength conversion of blue light emitted from the blue light emitting diodes; and a transparent layer allowing light emitted from the blue light emitting diodes to pass therethrough without wavelength conversion.

The light emitting diodes may be UV light emitting diodes and the phosphor layer may include a blue phosphor layer emitting blue light through wavelength conversion of UV light emitted from the UV light emitting diodes; a green phosphor layer emitting green light through wavelength conversion of UV light emitted from the UV light emitting diodes; and a red phosphor layer emitting red light through wavelength conversion of UV light emitted from the UV light emitting diodes.

The phosphor layer may emit white light through wavelength conversion of light emitted from the plurality of light emitting diodes.

The light emitting diode part may further include a support substrate disposed on a back surface of the color filter with the transparent electrode adjoining one surface of the color filter.

The light emitting diode part may further include a support substrate disposed on a back surface of the phosphor layer with the transparent electrode adjoining one surface of the phosphor layer.

The display apparatus may further include an anisotropic conductive film electrically connecting the light emitting diode part to the TFT panel part.

The method may further include: forming a phosphor layer on the support substrate; and forming a transparent electrode on the phosphor layer, wherein the plurality of light emitting diodes is formed on the transparent electrode formed on the phosphor layer.

The method may further include: forming a color filter on the support substrate; and forming a transparent electrode on the color filter, wherein the plurality of light emitting diodes is formed on the transparent electrode formed on the color filter.

The method may further include: forming a phosphor layer on the color filter, wherein the transparent electrode is formed on the phosphor layer.

The method may further include: forming a hole by etching the encapsulation layer surrounded by the first reflective electrode; and filling the hole with a phosphor layer.

The encapsulation layer may include at least one phosphor.

The display apparatus may further include a plurality of reflective electrodes disposed on the substrate to surround the plurality of light emitting diodes so as to be separated from side surfaces of the plurality of light emitting diodes.

The transparent electrode may be disposed to cover the plurality of light emitting diodes, the encapsulation layer and the plurality of reflective electrodes.

Each of the plurality of light emitting diodes may include a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer interposed between the first and second conductivity type semiconductor layers, and the transparent electrode may be electrically connected to the second conductivity type semiconductor layer.

Each of the plurality of light emitting diodes may include: a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer interposed between the first and second conductivity type semiconductor layers; an electrode disposed to cover the second conductivity type semiconductor layer and electrically connected to the second conductivity type semiconductor layer; and an insulating layer interposed between the second conductivity type semiconductor layer and the electrode and having a through-hole exposing part of the second conductivity type semiconductor layer, and the electrode may be electrically connected to the second conductivity type semiconductor layer through the through-hole.

The through-hole may have a smaller width than an upper surface of the second conductivity type semiconductor layer. The electrode and the insulating layer may be transparent.

A height from an upper surface of the substrate to an upper surface of the encapsulation layer may be greater than a height from the upper surface of the substrate to upper surfaces of the light emitting diodes.

The substrate may be a connection substrate having a plurality of conductive portions disposed between insulating portions.

The plurality of light emitting diodes may be electrically connected to some of the plurality of conductive portions and the plurality of TFTs may be electrically connected to the plurality of light emitting diodes through the plurality of conductive portions.

The display apparatus may further include a plurality of reflective electrodes disposed on the substrate to surround the plurality of light emitting diodes so as to be separated from side surfaces of the plurality of light emitting diodes, and the plurality of reflective electrodes may be electrically connected to other conductive portions.

The connection substrate may be a flexible substrate.

The insulating portions may include at least one of polydimethylpolysiloxane (PDMS), polyimide and ceramic, and the conductive portions may include a metal.

The display apparatus may further include a light conversion portion converting light emitted from the light emitting part and the light conversion portion may be coupled to one side of the light emitting part.

The light conversion portion may further include at least one of a phosphor layer emitting light through wavelength conversion of light emitted from the plurality of light emitting diodes and a color filter blocking light emitted from the plurality of light emitting diodes and having a predetermined wavelength.

Exemplary embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

Referring to Figure 1, the display apparatus 100 according to the first exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150.

The light emitting diode part 110 includes light emitting diodes 112, a support substrate 114, a phosphor layer 126, a transparent electrode 116, first reflective electrodes 117a, second reflective electrodes 117b, first connection electrodes 119, and an encapsulation layer 125.

The light emitting diode part 110 includes a plurality of light emitting diodes 112, which are regularly arranged on the support substrate 114. For example, the plurality of light emitting diodes 112 may be arranged at constant intervals in rows and columns. In this exemplary embodiment, the plurality of light emitting diodes 112 may include light emitting diodes emitting blue light or UV light.

In the display apparatus 100 according to this exemplary embodiment, the light emitting diode part 110 can be driven by power applied from an exterior power source. That is, each of the light emitting diodes 112 can be turned on or off in combination and light emitted from the light emitting diodes 112 is converted into red light, green light and blue light while passing through the phosphor layer 126. Accordingly, the light emitting diode part 110 of the display apparatus 100 can be driven without a separate LCD.

In this exemplary embodiment, a region including a single light emitting diode 112 may be used as a subpixel in the display apparatus 100 and one pixel may be composed of three or four subpixels. In the light emitting diode part, one subpixel may have a larger size than the light emitting diode 112 disposed in the subpixel.

Referring to Figure 1, each of the light emitting diodes 112 includes an n-type semiconductor layer 23, an active layer 25, a p-type semiconductor layer 27, an n-type electrode 31, a p-type electrode 33, and an insulating layer 37. Here, a light emitting structure 29 including the n-type semiconductor layer 23, the active layer 25 and the p-type semiconductor layer 27 may include Group III-V based compound semiconductors. By way of example, the n-type semiconductor layer 23, the active layer 25 and the p-type semiconductor layer 27 may include nitride semiconductors such as (Al, Ga, In)N. In other exemplary embodiments, locations of the n-type semiconductor layer 23 and the p-type semiconductor layer 27 can be interchanged.

The n-type semiconductor layer 23 may include an n-type dopant (for example, Si) and the p-type semiconductor layer 27 may include a p-type dopant (for example, Mg). The active layer 25 is interposed between the n-type semiconductor layer 23 and the p-type semiconductor layer 27. The active layer 25 may have a multi-quantum well (MQW) structure and the composition of the active layer 25 may be determined so as to emit light having a desired peak wavelength.

In this exemplary embodiment, the light emitting structure 29 including the n-type semiconductor layer 23, the active layer 25 and the p-type semiconductor layer 27 may have the shape of a vertical type light emitting diode. In this structure, the n-type electrode 31 may be formed on an outer surface of the n-type semiconductor layer 23 and the p-type electrode 33 may be formed on an outer surface of the p-type semiconductor layer 27.

In addition, each of the n-type electrode 31 and the p-type electrode 33 may be formed of an opaque metal. In this exemplary embodiment, since the n-type electrode 31 formed of the opaque metal is disposed to cover the entirety of the n-type semiconductor layer 23, light generated in the active layer 25 can be reflected by the n-type electrode 31 to be discharged through a side surface of the n-type semiconductor layer 23 even when passing through the n-type semiconductor layer 23.

Although the p-type electrode 33 covers the entirety of the p-type semiconductor layer 27, the p-type semiconductor layer 27 may form electrical contact in a partial area. That is, as shown in Figure 1, the insulating layer 37 may be disposed between the p-type electrode 33 and the p-type semiconductor layer 27. The insulating layer 37 is disposed to expose only a portion of the p-type semiconductor layer 27 while covering the remaining portion of the p-type semiconductor layer 27. Further, the p-type electrode 33 may electrically contact the exposed portion of the p-type semiconductor layer 27 exposed through the insulating layer 37. In this way, since the electrical contact area between the p-type electrode 33 and the p-type semiconductor layer 27 is reduced, it is possible to maintain current density in a certain level even when a small amount of current is supplied through the p-type electrode 33. Here, the region of the p-type semiconductor layer 27 exposed through the insulating layer 37 may be placed at the center of the p-type semiconductor layer 27.

For example, when the p-type semiconductor layer 27 has a total area of greater than 0 μm2 to 100 μm2, the region of the p-type semiconductor layer 27 exposed through the insulating layer 37 may have an area of greater than 0.1 μm2 to 25 μm2. Further, the insulating layer 37 may include SiO2.

As described above, in the structure wherein the n-type electrode 31, the insulating layer 37 and the p-type electrode 33 are disposed to cover the entirety of the n-type semiconductor layer 23 and the p-type semiconductor layer 27, light emitted from the active layer 25 can be discharged only through the side surface of the light emitting structure 29 instead of being discharged towards the n-type semiconductor layer 23 or the p-type semiconductor layer 27 (that is, in the vertical direction). Here, the n-type electrode 31 and the p-type electrode 33 may include a metal (for example, Al or Ag) that allows improvement in reflection efficiency while allowing power supply to the light emitting structure 29 therethrough.

The support substrate 114 serves to support the light emitting diode part 110 and may be an insulating substrate, a conductive substrate, or a printed circuit board. By way of example, the support substrate 114 may be at least one of a sapphire substrate, a gallium nitride substrate, a glass substrate, a silicon carbide substrate, a silicon substrate, a metal substrate, and a ceramic substrate. In this exemplary embodiment, the support substrate 114 may be a transparent substrate that allows light emitted from the light emitting diodes 112 to pass therethrough. By way of example, the support substrate 114 may be a flexible glass substrate having a certain thickness.

In this exemplary embodiment, the support substrate 114 may be a transparent substrate and may have one surface to which the phosphor layer 126 is coupled. The support substrate 114 may be coupled to the phosphor layer 126 via a transparent bonding layer.

The phosphor layer 126 may be disposed between the support substrate 114 and the plurality of light emitting diodes 112, and may include a blue phosphor layer 126a, a green phosphor layer 126b and a red phosphor layer 126c. The blue phosphor layer 126a, the green phosphor layer 126b and the red phosphor layer 126c may be alternately arranged to be adjacent to each other and may be separated from each other by a predetermined distance or more. A blocking layer 126d may be disposed between the blue phosphor layer 126a, the green phosphor layer 126b and the red phosphor layer 126c. Accordingly, the blocking layer 126d can prevent mixture of colors by blocking light having entered the blue phosphor layer 126a, the green phosphor layer 126b or the red phosphor layer 126c from entering other phosphor layers.

In this exemplary embodiment, the light emitting diodes 112 may be UV light emitting diodes. Accordingly, the blue phosphor layer 126a emits blue light through wavelength conversion of UV light emitted from the light emitting diodes 112 and the green phosphor layer 126b emits green light through wavelength conversion of UV light emitted from the light emitting diodes 112. The red phosphor layer 126c emit red light through wavelength conversion of UV light emitted from the light emitting diodes 112.

In the structure wherein the light emitting diodes 112 are blue light emitting diodes, a transparent layer may be provided in place of the blue phosphor layer 126a and disposed at the corresponding location thereof. As a result, blue light emitted from the light emitting diodes 112 can be discharged through the transparent layer outside without wavelength conversion.

Further, the transparent electrode 116 may be disposed between the phosphor layer 126 and the plurality of light emitting diodes 112. The transparent electrode 116 may have one surface directly adjoining the plurality of light emitting diodes 112 and may be coupled at the other surface thereof to the phosphor layer 126. The plurality of light emitting diodes 112 may be coupled to the transparent electrode 116 via a separate bonding portion and a transparent bonding layer may be interposed between the transparent electrode 116 and the phosphor layer 126.

The transparent electrode 116 may electrically contact the n-type electrodes 31 of the light emitting diodes 112 and may also electrically contact the first reflective electrodes 117a. Accordingly, power supplied from the first reflective electrodes 117a can be supplied to the n-type electrodes 31. In this exemplary embodiment, the transparent electrode 116 may be transparent to allow light emitted from the light emitting diode 112 to be discharged towards the phosphor layer 126 therethrough and may be as thin as possible. In this exemplary embodiment, the transparent electrode 116 may be formed of ITO.

The first and second

reflective electrodes

117a, 117b may have a predetermined thickness and may be disposed to surround the light emitting diodes 112. The first reflective electrode 117a is disposed to surround the side surface of the light emitting diode 112 and the second reflective electrode 117b is disposed to electrically contact the p-type electrode 33 of the light emitting diode 112. The size of one subpixel may be determined by the first and second

reflective electrodes

117a, 117b.

The first reflective electrode 117a is separated from the side surface of the light emitting diode 112 by a predetermined distance and may have an inclined side surface facing the light emitting diode 112, as shown in Figure 1. Here, the inclined side surface of the first reflective electrode 117a may be sloped in a direction such that light emitted from the light emitting diode 112 can be reflected towards the transparent electrode 116 thereby.

The first reflective electrode 117a may have a sidewall so as to set a region for one subpixel and may be integrally formed with a sidewall of a subpixel adjacent to the corresponding subpixel thereof. That is, the first reflective electrodes 117a are disposed to divide the transparent electrode 116 into a plurality of regions while adjoining the transparent electrode 116. In the display apparatus 100, the plural regions correspond to subpixels, respectively, and at least one light emitting diode 112 may be disposed in each subpixel.

The second reflective electrode 117b may be electrically connected to the p-type electrode 33 of the light emitting diode 112 and may have a plate shape. The second reflective electrode 117b is disposed to cover the entirety of the p-type electrode 33 and may have a larger area than the light emitting diode 112. As a result, light emitted from the light emitting diode 112 can be reflected towards the transparent electrode 116 by the second reflective electrode 117b. The second reflective electrode 117b may be separated from the first reflective electrode 117a by a predetermined distance or more so as to be electrically insulated therefrom.

In this exemplary embodiment, the first and second

reflective electrodes

117a, 117b may be connected to a power source to supply power to the light emitting diodes 112 and include a material capable of reflecting light. To this end, each of the first and second

reflective electrodes

117a, 117b may include a metal.

The first connection electrode 119 is interposed between the p-type electrode 33 and the second reflective electrode 117b and electrically connects the p-type electrode 33 to the second reflective electrode 117b. In this exemplary embodiment, the first connection electrode 119 may have the same width as the p-type electrode 33 and a greater thickness than the p-type electrode 33.

The encapsulation layer 125 may fill the subpixels defined by the first and second

reflective electrodes

117a, 117b. With this structure, the encapsulation layer 125 may be disposed to cover all of the light emitting diodes 112. In this exemplary embodiment, the encapsulation layer 125 may include a transparent and electrically insulating material. Thus, light emitted from the light emitting diodes 112 can be discharged through the encapsulation layer 125.

The TFT panel part 130 is coupled to the light emitting diode part 110 and serves to supply power to the light emitting diode part 110. To this end, the TFT panel part 130 includes a panel substrate 132 and second connection electrodes 134. The TFT panel part 130 can control power supply to the light emitting diode part 110 to allow only some of the light emitting diodes 112 in the light emitting diode part 110 to emit light.

The panel substrate 132 may have a TFT drive circuit therein. The TFT drive circuit may be a circuit for driving an active matrix (AM) or a circuit for driving a passive matrix (PM).

The second connection electrodes 134 are electrically connected to the TFT drive circuit of the panel substrate 132 and to the second connection electrodes 117b of the light emitting diode part 110. In this structure, power supplied through the TFT drive circuit can be supplied to each of the light emitting diodes 112 through the second connection electrodes 134 and the second reflective electrodes 117b. In this exemplary embodiment, the second connection electrodes 134 may be covered by a separate protective layer, which may include, for example, SiNx.

The anisotropic conductive film 150 serves to electrically connect the light emitting diode part 110 to the TFT panel part 130. The anisotropic conductive film 150 may include an adhesive organic insulating material and may contain conductive particles uniformly dispersed therein to achieve electrical connection. The anisotropic conductive film 150 exhibits conductivity in the thickness direction thereof and insulating properties in the plane direction thereof. In addition, the anisotropic conductive film 150 exhibits adhesive properties. Thus, the anisotropic conductive film 150 may be used to bond the light emitting diode part 110 to the TFT panel part 130 such that the light emitting diode part 110 can be electrically connected to the TFT panel part 130 therethrough.

Particularly, the anisotropic conductive film 150 may be advantageously used to connect ITO electrodes which are difficult to solder at high temperature.

As such, in the structure wherein the light emitting diodes 112 are coupled to the TFT panel part 130 via the anisotropic conductive film 150, the second reflective electrodes 117b can be electrically connected to the second connection electrodes 134 of the TFT panel part 130 via an electrode connection portion 152.

In this exemplary embodiment, the light emitting diode part 110 and the TFT panel part 130 may be separately manufactured, and coupling between the light emitting diode part 110 and the TFT panel part 130 will be described below.

Figure 2 is sectional views illustrating a process of manufacturing the light emitting diodes of the display apparatus according to the first exemplary embodiment.

The process of manufacturing the plurality of light emitting diodes 112 will be described in more detail with reference to Figure 2. Referring to Figure 2A, an n-type electrode 31 having a predetermined area is disposed on a first manufacturing substrate 21a, and an n-type semiconductor layer 23, an active layer 25, and a p-type semiconductor layer 27 are sequentially stacked on the n-type electrode 31. In this exemplary embodiment, the first manufacturing substrate 21a may be a sapphire substrate, a gallium nitride substrate, a glass substrate, a silicon carbide substrate, a silicon substrate, a metal substrate, a ceramic substrate, or the like.

Then, referring to Figure 2B, an insulating layer 37 is formed to a predetermined thickness on the p-type electrode 33. Thereafter, the insulating layer 37 is subjected to etching to form holes so as to expose the p-type semiconductor layer 27 at locations corresponding to light emitting diodes 112, and a p-type electrode 33 is formed on the insulating layer 37 so as to cover the entirety of the insulating layer 37 as well as the holes formed in the insulating layer 37. With this structure, the p-type electrode 33 can electrically contact the p-type semiconductor layer 27 through the holes.

Referring to Figure 2C, a plurality of first connection electrodes 119 is disposed on the p-type electrode 33. The first connection electrodes 119 may be disposed on the holes formed in the insulating layer 37, respectively. Here, the plurality of first connection electrodes 119 may be separated from each other on the p-type electrode 33 by a predetermined distance or more.

After formation of the first connection electrodes 119, the p-type electrode 33, the insulating layer 37, the p-type semiconductor layer 27, the active layer 25, the n-type semiconductor layer 23 and the n-type electrode 31 are etched with respect to each of the first connection electrodes 119. As a result, a plurality of light emitting diodes 112 may be formed on the first manufacturing substrate 21a, as shown in Figure 2D. In this exemplary embodiment, each of the light emitting diodes 112 may include a trapezoidal light emitting structure 29 formed by etching.

In order to transfer the plurality of light emitting diodes 112 to the support substrate 114, the plurality of light emitting diodes 112 is covered with a filler 125a, as shown in Figure 2E. Then, referring to Figure 2F, a second manufacturing substrate 21b is bonded to an upper side of the filler 125a. The second manufacturing substrate 21b may be the same substrate as the first manufacturing substrate 21a or may be a different substrate than the first manufacturing substrate, as needed. After the second manufacturing substrate 21b is coupled to the upper side of the filler 125a, the first manufacturing substrate 21a is removed, as shown in Figure 2G.

The phosphor layer 126 to be coupled to the plurality of light emitting diodes 112 may be formed independent of the plurality of light emitting diodes 112 manufactured as shown in Figure 2. Referring to Figure 3A, the blocking layer 126d is formed in plural regions arranged at constant intervals on the support substrate 114, and each region between the regions for the blocking layer 126d corresponds to a subpixel of the display apparatus 100.

After the blocking layer 126d is formed on the support substrate 114, a red phosphor layer 126c may be formed in plural regions defined by the regions in which the blocking layer 126d is formed. The red phosphor layer 126c is formed in a plurality of regions arranged at constant intervals and may be formed by dotting a liquid resin containing red phosphors, followed by curing.

Then, as in the process of forming the red phosphor layer 126c, each of a blue phosphor layer 126a and a green phosphor layer 126b is formed, as shown in Figure 3C and Figure 3D. In this exemplary embodiment, when the light emitting diodes 112 are blue light emitting diodes, a transparent encapsulation layer 125 may be formed instead of the blue phosphor layer 126a.

As described above, after all of the

phosphor layers

126a, 126b, 126c are formed, a transparent electrode 116 may be disposed on the phosphor layer 126, as shown in Figure 3E. The transparent electrode 116 acts not only to supply power to the light emitting diodes 112 but also to protect the phosphor layer 126.

Figure 4 is sectional views illustrating a process of manufacturing the light emitting diode part of the display apparatus according to the first exemplary embodiment.

The light emitting diode part 110 may be manufactured by coupling the light emitting diodes 112 and the phosphor layer 126 manufactured as shown in Figure 2 and Figure 3. As shown in Figure 4A, the plurality of light emitting diodes 112 disposed on the second manufacturing substrate 21b is brought into contact with the transparent electrode 116 to which a bonding agent may be applied. The bonding agent may be deposited only to some locations of the transparent electrode 116 corresponding to a location at which the phosphor layer 126 is formed. As a result, among the plurality of light emitting diodes 112, only the light emitting diodes 112 contacting the bonding agent can be coupled to the transparent electrode 116.

Figure 4B shows the plurality of light emitting diodes 112 coupled to the transparent substrate. That is, in this exemplary embodiment, the plurality of light emitting diodes 112 may be coupled to the transparent electrode 116 such that one light emitting diode is provided to one subpixel.

After the plurality of light emitting diodes 112 is coupled to the transparent electrode 116, the encapsulation layer 125 may be formed to cover each of the light emitting diodes 112 and the transparent electrode 116. The encapsulation layer 125 may be formed of an electrically insulating material and may be transparent. Figure 4C shows the encapsulation layer 125 formed to cover each of the light emitting diodes 112.

Next, referring to Figure 4D, the encapsulation layer 125 is subjected to etching to expose upper surfaces of the first connection electrodes 119. Etching of the encapsulation layer 125 may be performed to expose part of the first connection electrodes 119 without exposing the p-type electrode 33 or the p-type semiconductor layer 27.

Then, referring to Figure 4E, with reference to the exposed regions of the first connection electrode 119, each region between the light emitting diodes 112 is subjected to etching to form a first hole H1. The shape of the subpixel may be determined by the first hole H1. That is, since the encapsulation layer 125 is etched such that an inner side surface of the first hole H becomes an inclined surface, a plurality of mesas may be formed on the transparent electrode 116. In this exemplary embodiment, one mesa may receive at least one light emitting diode 112 therein and the encapsulation layer 125 may be configured to surround at least one light emitting diode 112.

After the first holes H1 are formed as described above, second reflective electrodes 117b are formed on the first connection electrodes 119, as shown in Figure 4F. The second reflective electrodes 117b may have a plate shape having a greater width than the light emitting diodes 112. Further, each of the first reflective electrodes 117a may be formed in the first hole H1 so as to correspond to the shape of the first hole. The first reflective electrode 117a may have an inclined side surface corresponding to the shape of the first hole H1 and may have the same height as a distance from the transparent electrode 116 to an upper surface of the second reflective electrode 117b.

As the first and second

reflective electrodes

117a, 117b are formed as described above, manufacture of the light emitting diode part 110 according to this exemplary embodiment is completed.

After completion of manufacture of the light emitting diode part 110 through the processes shown in Figure 2 to Figure 4, the light emitting diode part 110 is coupled to a separate TFT panel part 130, and Figure 5 shows this process.

The TFT panel part 130 may be manufactured in a large area and may be provided with a second connection electrode 134 and a TFT circuit at a location corresponding to each subpixel. Thus, as shown in Figure 5A, a light emitting diode part 110 having a smaller size than the TFT panel part 130 having a large area is coupled to part of the TFT panel part 130. In this exemplary embodiment, the TFT panel part 130 has an anisotropic conductive film 150 attached to an upper side thereof and the light emitting diode part 110 is disposed on the anisotropic conductive film 150 such that the second reflective electrodes 117b adjoin the second connection electrodes 134. In addition, the light emitting diode part 110 is coupled to the TFT panel part 130 by imparting force from above the light emitting diode part 110 towards the TFT panel part 130 such that the anisotropic conductive film 150 is compressed to electrically connect the second reflective electrodes 117b to the second connection electrodes 134.

Then, referring to Figure 5B, another light emitting diode part 110 may be coupled to the TFT panel part 130, thereby providing a finished display apparatus 100.

Referring to Figure 6, the display apparatus 100 according to the second exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150.

The light emitting diode part 110 includes light emitting diodes 112, a support substrate 114, a color filter 127, a transparent electrode 116, first reflective electrodes 117a, second reflective electrodes 117b, first connection electrodes 119, a phosphor layer 126, and an encapsulation layer 125. In description of the second exemplary embodiment, descriptions of the same components as the first exemplary embodiment will be omitted.

In this exemplary embodiment, the color filter 127 may be interposed between the support substrate 114 and the transparent electrode 116. The color filter 127 may include a blue light portion 127a, a green light portion 127b, a red light portion 127c, and a light blocking portion 127d. The color filter 127 may be formed in a film shape and can block light having passed through the color filter 127 excluding light of a predetermined wavelength.

That is, the blue light portion 127a allows only blue light to pass therethrough by blocking light having other wavelengths excluding the wavelength of blue light, and the green light portion 127b allows only green light to pass therethrough by blocking light having other wavelengths excluding the wavelength of green light. The red light portion 127c allows only red light to pass therethrough by blocking light having other wavelengths excluding the wavelength of red light. The light blocking portion 127d is disposed between the blue light portion 127a, the green light portion 127b and the red light portion 127c, and blocks all fractions of light.

In addition, a region defined by each of the first reflective electrodes 117a may be provided with the encapsulation layer 125 alone, the encapsulation layer 125 and the green phosphor layer 126b, or the encapsulation layer 125 and the red phosphor layer 126c. The encapsulation layer 125 is disposed to surround a side surface of the light emitting diode 112. Each of the green phosphor layer 126b and the red phosphor layer 126c may be disposed to surround the encapsulation layer 125. With this structure, the green phosphor layer 126b and the red phosphor layer 126c may be disposed between the encapsulation layer 125 and the first reflective electrode 117a.

In this exemplary embodiment, the blue light emitting diodes are used as the light emitting diodes 112. Thus, the description is given of the structure wherein the encapsulation layer 125 is used instead of a separate blue phosphor layer 126a.

Specifically, referring to Figure 6, in the first subpixel, the encapsulation layer 125 is disposed to surround the side surface of the light emitting diode 112 and the red phosphor layer 126c is disposed between the encapsulation layer 125 and the first reflective electrode 117a. In addition, the red light portion 127c of the color filter 127 is disposed above the light emitting diode 112. In this structure, blue light emitted through the side surface of the light emitting diode 112 passes through the encapsulation layer 125 and is converted into red light through the red phosphor layer 126c. Light converted into red light through the red light portion 127c of the color filter 127 is discharged outside through the transparent electrode 116.

Referring again to Figure 6, in the second subpixel, the encapsulation layer 125 is disposed to surround the side surface of the light emitting diode 112 and the green phosphor layer 126b is disposed between the encapsulation layer 125 and the first reflective electrode 117a. In addition, the green light portion 127b of the color filter 127 is disposed above the light emitting diode 112. In this structure, blue light emitted through the side surface of the light emitting diode 112 passes through the encapsulation layer 125 and is converted into green light through the green phosphor layer 126b, whereby only the green light can be discharged outside through the green light portion 127b.

Referring again to Figure 6, in the third subpixel, only the encapsulation layer 125 is disposed between the blue light emitting diode and the first reflective electrode 117a. In addition, the blue light portion 127a of the color filter 127 is disposed above the light emitting diodes 112. In this structure, blue light emitted through the side surface of the light emitting diode 112 passes through the encapsulation layer 125 without wavelength conversion, whereby only the blue light can be discharged outside through the blue light portion 127a.

In this exemplary embodiment, the blue light emitting diodes are used as the light emitting diodes 112. Thus, the description is given of the structure wherein the third subpixel is provided only with the encapsulation layer 125. However, it should be understood that, when UV light emitting diodes are used as the light emitting diodes 112, the blue phosphor layer 126a may be disposed together with the encapsulation layer 125, and UV light emitted from the light emitting diodes is converted into blue light through the blue phosphor layer 126a and only the blue light can be discharged outside through the blue light portion 127a.

Figure 7 is sectional views illustrating a process of manufacturing the light emitting diode part of the display apparatus according to the second exemplary embodiment, and Figure 8 is sectional views illustrating a process of coupling a TFT panel part to the light emitting diode part of the display apparatus according to the second exemplary embodiment.

Referring to Figure 7, the process of manufacturing the light emitting diode part 110 according to this exemplary embodiment will be described. Figure 7A corresponds to Figure 4C and the processes prior to this process are similar to those of the first exemplary embodiment. The second exemplary embodiment is different from the first exemplary embodiment in that the color filter 127 is disposed at the location of the phosphor layer 126.

That is, Figure 7A shows a structure wherein a plurality of light emitting diodes 112 is disposed on the transparent electrode 116 having the color filter 127 at a lower side thereof and an encapsulation layer 125 is formed to cover the plurality of light emitting diodes 112.

After formation of the encapsulation layer 125, the encapsulation layer 125 is subjected to etching to expose an upper side of the first connection electrode 119 of each of the light emitting diodes 112 and first holes H1 are formed between the light emitting diodes 112, as shown in Figure 7B.

Then, as shown in Figure 7C, a second reflective electrode 117b is disposed on each of the first connection electrodes 119 and a first reflective electrode 117a is formed in each of the first holes H1.

After formation of the first and second

reflective electrodes

117a, 117b, second holes H2 are formed by etching the encapsulation layer 125 disposed at the sides of the light emitting diodes 112 through spaces between the first reflective electrodes 117a and the second reflective electrodes 117b, as shown in Figure 7D. In this exemplary embodiment, since the blue light emitting diodes are used as the light emitting diodes 112, the second holes H2 are formed by etching the encapsulation layer 112 at the sides of the light emitting diodes 112 excluding the light emitting diodes 112 disposed at a location corresponding to a blue light portion 127a of the color filter 127.

Obviously, when UV light emitting diodes are used as the light emitting diodes, the second holes H2 are formed in all of the subpixels.

After the second holes H2 are respectively formed on the subpixels as described above, each of a green phosphor layer 126b and a red phosphor layer 126c is formed so as to fill the corresponding second hole H2, as shown in Figure 7E. In this exemplary embodiment, the green phosphor layer 126b fills the second hole H2 formed above the green light portion 127b of the color filter 127, and the red phosphor layer 126c fills the second hole H2 formed above the red light portion 127c of the color filter 127. In addition, the second hole H2 is not formed above the blue light portion 127a of the color filter 127 and the encapsulation layer 125 is disposed above the blue light portion 127a.

As such, the phosphor layer 126 is formed on each of the subpixels as described above, thereby completing manufacture of the light emitting diode part 110. Then, the display apparatus 100 can be manufactured by coupling the manufactured light emitting diode part 110 to a large TFT panel part 130, as shown in Figure 7A and Figure 7B.

Referring to Figure 9, the display apparatus 100 according to the third exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150.

The light emitting diode part 110 includes light emitting diodes 112, a support substrate 114, a color filter 127, a phosphor layer 126, a transparent electrode 116, first reflective electrodes 117a, second reflective electrodes 117b, first connection electrodes 119, and an encapsulation layer 125. In description of the third exemplary embodiment, descriptions of the same components as the first and second exemplary embodiments will be omitted.

In this exemplary embodiment, the color filter 127 and the phosphor layer 126 may be interposed between the support substrate 114 and the transparent electrode 116. The color filter 127 may include a blue light portion 127a, a green light portion 127b, a red light portion 127c, and a light blocking portion 127d. The color filter 127 may be formed in a film shape and can block light having passed through the color filter 127 excluding light of a predetermined wavelength.

The phosphor layer 126 is interposed between the color filter 127 and the transparent electrode 116 and acts to emit light through wavelength conversion of light entering the phosphor layer 126 or without wavelength conversion. That is, in this exemplary embodiment, the phosphor layer 126 may include a green phosphor layer 126b, a red phosphor layer 126c, a blocking layer 126d, and a transparent layer. The green phosphor layer 126b is disposed at a location corresponding to the green light portion 127b of the color filter 127 and the red phosphor layer 126c is disposed at a location corresponding to the red light portion 127c of the color filter 127. The transparent layer is disposed at a location corresponding to the blue light portion 127a of the color filter 127.

In this exemplary embodiment, since the blue light emitting diodes are used as the light emitting diodes 112, the phosphor layer 126 includes the transparent layer. In the structure wherein UV light emitting diodes are used as the light emitting diodes 112, the blue phosphor layer 126a may be disposed in place of the transparent layer.

As in the first exemplary embodiment, the encapsulation layer 125 may be disposed between the light emitting diodes 112 and the first reflective electrode 117a.

Referring to Figure 10, the display apparatus 100 according to the fourth exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150.

The light emitting diode part 110 includes light emitting diodes 112, a support substrate 114, a color filter 127, a white phosphor layer 126f, a transparent electrode 116, first reflective electrodes 117a, second reflective electrodes 117b, first connection electrodes 119, and an encapsulation layer 125. In description of the fourth exemplary embodiment, descriptions of the same components as the first to third exemplary embodiments will be omitted.

In this exemplary embodiment, the color filter 127 and the white phosphor layer 126f may be interposed between the support substrate 114 and the transparent electrode 116. The color filter 127 may include a blue light portion 127a, a green light portion 127b, a red light portion 127c, and a light blocking portion 127d.

The white phosphor layer 126f is interposed between the color filter 127 and the transparent electrode 116 and can emit white light through wavelength conversion of light entering the white phosphor layer 126f. In addition, the light blocking layer 126d may be disposed at a location corresponding to the light blocking portion 127d of the color filter 127.

By the color filter 127 and the white phosphor layer 126f, light emitted from each of the light emitting diodes 112 is discharged towards the transparent electrode 116 through the encapsulation layer 125, passes through the transparent electrode 116, and is converted into white light through wavelength conversion by the white phosphor layer 126f such that white light is emitted to the color filter 127. As a result, light is discharged outside through the color filter 127 except for light having a certain wavelength.

That is, the blue light portion 127a of the color filter 127 allows only blue light to pass therethrough by blocking light having other wavelengths excluding the wavelength of blue light among white light passing therethrough, and the green light portion 127b of the color filter 127 allows only green light to pass therethrough by blocking light having other wavelengths excluding the wavelength of green light among white light passing therethrough. In addition, the red light portion 127c allows only red light to pass therethrough by blocking light having other wavelengths excluding the wavelength of red light among white light passing therethrough.

Referring to Figure 11, the display apparatus 100 according to the fifth exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150.

The light emitting diode part 110 includes light emitting diodes 112, a support substrate 114, a color filter 127, a transparent electrode 116, first reflective electrodes 117a, second reflective electrodes 117b, first connection electrodes 119, and a white phosphor layer 126f. In description of the fifth exemplary embodiment, descriptions of the same components as the first to fourth exemplary embodiments will be omitted.

In this exemplary embodiment, the color filter 127 may be interposed between the support substrate 114 and the transparent electrode 116. As in the above exemplary embodiments, the color filter 127 may include a blue light portion 127a, a green light portion 127b, a red light portion 127c, and a light blocking portion 127d.

The white phosphor layer 126f may be disposed between the light emitting diode 112 and the first reflective electrode 117a. That is, in this exemplary embodiment, the white phosphor layer 126f may be disposed at the location of the encapsulation layer 125 described in the first exemplary embodiment, instead of the encapsulation layer 125. In this structure, light emitted from each of the light emitting diodes 112 is subjected to wavelength conversion while passing through the white phosphor layer 126f such that white light can be discharged towards the transparent electrode 116.

Then, white light having passed through the transparent electrode 116 passes through the color filter 127 such that only blue light, green light and red light can be discharged outside through the color filter.

Referring to Figure 12, the display apparatus 100 according to the sixth exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150.

The light emitting diode part 110 includes light emitting diodes 112, a transparent electrode 116, first reflective electrodes 117a, second reflective electrodes 117b, first connection electrodes 119, a phosphor layer 126, and an encapsulation layer 125. In description of the sixth exemplary embodiment, descriptions of the same components as the first and second exemplary embodiments will be omitted.

The display apparatus 100 does not include the support substrate 114 and the color filter 127 of the display apparatus 100 according to the second exemplary embodiment. That is, light emitted from each of the light emitting diodes 112 is blue light, which in turn is converted into red light while passing through the encapsulation layer 125 and the red phosphor layer 126c. In addition, blue light emitted from the light emitting diodes 112 is converted into green light while passing through the encapsulation layer 125 and the green phosphor layer 126b. Further, a subpixel on which the encapsulation layer 125 alone is disposed allows blue light emitted from the light emitting diodes 112 to be discharged outside through the encapsulation layer 125 without wavelength conversion.

Referring to Figure 13, the display apparatus 100 according to the seventh exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150.

The light emitting diode part 110 includes blue light emitting diodes 112a, green light emitting diodes 112b, red light emitting diodes 112c, a transparent electrode 116, first reflective electrodes 117a, second reflective electrodes 117b, first connection electrodes 119, and an encapsulation layer 125. In description of the seventh exemplary embodiment, descriptions of the same components as the first and second exemplary embodiments will be omitted.

Each of the blue light emitting diode 112a, the green light emitting diode 112b and the red light emitting diode 112c is provided in plural and regularly arranged on the transparent electrode 116. The blue light emitting diodes 112a, the green light emitting diodes 112b and the red light emitting diodes 112c may be disposed adjacent to one another and arranged at constant intervals in rows and columns.

In addition, one of the blue light emitting diode 112a, the green light emitting diode 112b and the red light emitting diodes 112c is provided to one subpixel.

The encapsulation layer 125 is disposed to surround the side surface of each of the blue light emitting diodes 112a, the green light emitting diodes 112b and the red light emitting diodes 112c. Due to the same reason as for the provision of the encapsulation layer 125 in the other exemplary embodiments, the encapsulation layer 125 can prevent damage to each of the light emitting diodes 112a, 112b, 112c due to external environments and exhibits electrical insulating properties.

Accordingly, light emitted from the blue light emitting diodes 112a, the green light emitting diodes 112b and the red light emitting diodes 112c can be discharged outside through the encapsulation layer 125 and the transparent electrode 116.

Figure 14 is a sectional view of a display apparatus according to an eighth exemplary embodiment of the present disclosure and Figure 15 is an enlarged view of part A of Figure 14.

Referring to Figure 14, the display apparatus 100 according to the eighth exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150. The light emitting diode part 110 includes a light emitting part 111 and a light conversion part 123.

The light emitting part 111 includes light emitting diodes 112, a connection substrate 113, a transparent electrode 116, reflective electrodes 117, and an encapsulation layer 125. The light emitting diodes 112 are provided in plural and regularly arranged with reference to the connection substrate 113. By way of example, the plurality of light emitting diodes 112 may be arranged at constant intervals in rows and columns. In this exemplary embodiment, blue or UV light emitting diodes are used as the light emitting diodes 112. In addition, the light emitting diodes 112 may be green or red light emitting diodes. In this way, since different kinds of light emitting diodes 112 are disposed on the connection substrate 113, the light conversion part 123 may be changed.

The display apparatus 100 according to this exemplary embodiment can be driven when power is applied from an exterior power source to each of the light emitting diodes 112 of the light emitting diode part 110. That is, each of the light emitting diodes 112 can be turned on or off in combination and light emitted from the light emitting diodes 112 is converted into red light, green light and blue light while passing through the light conversion part 123. Accordingly, the light emitting diode part 110 of the display apparatus 100 can be driven without a separate LCD. Alternatively, in the structure wherein the plurality of light emitting diodes 112 is composed of blue, green and red light emitting diodes, the light conversion part 123 can be omitted.

Referring to Figure 14, each of the light emitting diodes 112 may include an n-type semiconductor layer 23, an active layer 25, a p-type semiconductor layer 27, a p-type electrode 33, and an insulating layer 37. Here, a light emitting structure 29 including the n-type semiconductor layer 23, the active layer 25 and the p-type semiconductor layer 27 may include Group III-V based compound semiconductors. By way of example, the n-type semiconductor layer 23, the active layer 25 and the p-type semiconductor layer 27 may include nitride semiconductors such as (Al, Ga, In)N. In other exemplary embodiments, locations of the n-type semiconductor layer 23 and the p-type semiconductor layer 27 may be interchanged.

The n-type semiconductor layer 23 may include an n-type dopant (for example, Si) and the p-type semiconductor layer 27 may include a p-type dopant (for example, Mg). The active layer 25 is interposed between the n-type semiconductor layer 23 and the p-type semiconductor layer 27 and may have a multi-quantum well (MQW) structure, and the composition of the active layer 25 may be determined so as to emit light having a desired peak wavelength.

In this exemplary embodiment, the light emitting structure 29 including the n-type semiconductor layer 23, the active layer 25 and the p-type semiconductor layer 27 may have the shape of a vertical type light emitting diode. Further, an n-type electrode may be formed on an outer surface of the n-type semiconductor layer 23, the p-type electrode 33 may be formed on an outer surface of the p-type semiconductor layer 27, and the n-type electrode and the p-type electrode 33 may be omitted, as needed. In this exemplary embodiment, the n-type electrode is omitted.

Further, in this exemplary embodiment, the p-type electrode 33 may be formed of a transparent material. In this exemplary embodiment, although the p-type electrode 33 is disposed to cover the entirety of the p-type semiconductor layer 27, an electrical contact area between the p-type electrode 33 and the p-type semiconductor layer 27 may be smaller than the area of the p-type electrode 33. Namely, as shown in Figure 14, the insulating layer 37 may be formed between the p-type electrode 33 and the p-type semiconductor layer 27 and may be disposed to expose only part of the p-type semiconductor layer 27 while covering the entirety of the remaining part of the p-type semiconductor layer 27. With this structure, the p-type electrode 33 may electrically contact the p-type semiconductor layer 27 at a location at which the p-type semiconductor layer 27 is exposed through the insulating layer 37.

As described above, with the structure wherein the electrical contact area between the p-type electrode 33 and the p-type semiconductor layer 27 is smaller than the area of an upper surface of the p-type semiconductor layer 27, current density can be relatively increased even when small electric current is supplied through the p-type electrode 33. In this exemplary embodiment, the location at which the p-type semiconductor layer 27 is exposed through the insulating layer 37 may be the center of the upper surface of the p-type semiconductor layer 27.

Referring to Figure 15, the total width W1 of the p-type semiconductor layer 27 of the light emitting structure 29 may be greater than the width W2 of the region of the p-type semiconductor layer 27 exposed through the insulating layer 37 (W2<W1). For example, when the total width W1 of the p-type semiconductor layer 27 is 10 μm or less, the region of the p-type semiconductor layer 27 exposed through the insulating layer 37 may have a width W2 of 1 μm or less.

In this exemplary embodiment, a relationship between the width of the region of the p-type semiconductor layer 27 exposed through the insulating layer 37 and the total width of the p-type semiconductor layer 27 will be described below.

In this exemplary embodiment, both the p-type electrode 33 and the insulating layer 37 may be formed of transparent materials. The p-type electrode 33 may be formed of a transparent material, such as ITO, and the insulating layer 37 may be formed of a transparent insulating material, such as SiNX. Here, although the p-type electrode 33 and the insulating layer 37 may be transparent with respect to light in any wavelength bands, the p-type electrode 33 and the insulating layer 37 may be formed of any transparent material with respect to light having a peak wavelength in the range of 360 nm to 470 nm in the structure wherein the light emitting diodes 112 according to this exemplary embodiment are blue or UV light emitting diodes 112.

The connection substrate 113 serves to support the light emitting part 111 and may be selected from any kind of substrate. In this exemplary embodiment, the connection substrate 113 may be an insulating substrate that exhibits conductivity at some parts thereof. That is, although most of the connection substrate 113 exhibits insulating properties, some portions of the connection substrate 113 adjoining the light emitting diodes 112 and the reflective electrodes 117 can exhibit conductivity. To this end, the connection substrate 113 may include conductive portions 113a and insulating portions 113b. In addition, the conductive portions 113a are formed from an upper surface of the connection substrate 113 to a lower surface thereof through the connection substrate 113 to allow electrical conduction between the upper surface of the connection substrate 113 and the lower surface thereof.

Such a connection substrate 113 may be prepared by forming a plurality of holes through an electrically insulating substrate such that the holes are formed through the substrate, followed by filling the holes with a conductive material (for example, Cu). As a result, the connection substrate 113 includes a plurality of conductive portions 113a, which are electrically insulated from one another by the insulating portions 113b.

The connection substrate 113 may be a flexible substrate. As a result, the connection substrate 113 can be coupled to a planar TFT panel part 130 or a curved TFT panel part 130. In this exemplary embodiment, the insulating portions 113b of the connection substrate 113 may include polydimethylpolysiloxane (PDMS), polyimide, ceramic, or a mixture thereof. The conductive portions 113a may include a metal having high electrical conductivity (for example, copper (Cu), gold (Au), or silver (Ag)).

After the connection substrate 113 is formed, the light emitting diodes 112 are disposed on the conductive portions 113a of the connection substrate 113. In this exemplary embodiment, the n-type semiconductor layer 23 of each of the light emitting diodes 112 may be secured to the conductive portion 113a of the connection substrate 113 by a bonding agent S.

As described above, in the connection substrate 113, the conductive portions 113a exhibit electrical conductivity and the insulating portions 113b exhibit electrical insulating properties, and both the conductive portions 113a and the insulating portions 113b may include a material capable of reflecting light emitted from the light emitting diodes 112. Accordingly, light emitted from the light emitting diodes 112 can be reflected by the connection substrate 113 towards the reflective electrodes 117 or in an upward direction.

The transparent electrode 116 may electrically contact the p-type electrodes 33 of the light emitting diodes 112 and may also electrically contact the reflective electrodes 117. With this structure, power supplied from the reflective electrodes 117 can be supplied to a p type side. In this exemplary embodiment, the transparent electrode 116 may be transparent to allow light emitted from the light emitting diodes 112 to be directed to the light conversion part 123 therethrough and may be as thin as possible. In this exemplary embodiment, the transparent electrode 116 may be formed of ITO.

Each of the reflective electrodes 117 may have a predetermined thickness and be disposed to surround the light emitting diode 112. The reflective electrode 117 is disposed to surround the side surface of the light emitting diode 112 and may be separated from the light emitting diode 112 by a predetermined distance. Thus, the size of one subpixel may be determined by the reflective electrode 117.

In this exemplary embodiment, the reflective electrode 117 may have an inclined side surface facing the light emitting diode 112, as shown in Figure 14. Here, the inclined surface of the reflective electrode 117 may be sloped in a direction capable of reflecting light emitted from the light emitting diode 112 towards the transparent electrode 116.

Further, the reflective electrode 117 may have a sidewall formed to set a region for one subpixel and integrated with a sidewall of another subpixel adjacent to the corresponding subpixel. That is, the reflective electrodes 117 may be disposed such that upper portions of the reflective electrodes 117 divide the transparent electrode 116 into a plurality of regions while adjoining the transparent electrode 116, and lower portions of the reflective electrodes 117 may electrically contact the conductive portions of the connection substrate 113.

Each of the regions divided by the reflective electrodes 117 acts as a subpixel in the display apparatus 100 and each subpixel may be provided with at least one light emitting diode 112.

The encapsulation layer 125 may fill the subpixel regions defined by the reflective electrodes 117. In this exemplary embodiment, the encapsulation layer 125 fills spaces between the side surfaces of the light emitting diodes 112 and the inclined surfaces of the reflective electrodes 117 and may have a greater height than the light emitting diodes 112. Even with this structure, the encapsulation layer 125 may be disposed so as not to cover upper surfaces of the light emitting diodes 112. That is, the encapsulation layer 125 may be configured to surround only the side surfaces of the light emitting diodes 112 while exposing the upper surfaces of the light emitting diodes 112. As a result, grooves are formed on the upper surfaces of the light emitting diodes 112 and the encapsulation layer fills the spaces between the light emitting diodes 112 and the reflective electrodes 117. The encapsulation layer 125 may be a transparent material that exhibits electrical insulating properties. Thus, light emitted from the light emitting diodes 112 can be discharged through the encapsulation layer 125.

Referring to Figure 15, the following description will focus on the height h2 of the encapsulation layer 125 filling spaces between the reflective electrodes 117. The height h2 of the encapsulation layer 125 refers to a height from the upper surface of the connection substrate 113. Further, the height h1 of the light emitting diodes 112 also refers to a height from the upper surface of the connection substrate 113. The height h2 of the encapsulation layer 125 is greater than the height h1 of the light emitting diodes 112 and is less than the height of the reflective electrodes 117. Since the encapsulation layer 125 fills the spaces between the reflective electrodes 117, the height h2 of the encapsulation layer 125 is less than the height of the reflective electrodes 117.

In addition, as described above, the height h2 of the encapsulation layer 125 is greater than the height h1 of light emitting diodes 112. In this exemplary embodiment, since the height h2 of the encapsulation layer 125 is greater than the height h1 of the light emitting diodes 112 and the encapsulation layer 125 is not disposed on the light emitting diodes 112, there is no problem of electrical contact between the p-type electrodes 33 of the light emitting diodes 112 and the transparent electrode 116 even when the locations of the light emitting diodes 112 are changed in a manufacturing process.

That is, the transparent electrode 116 is disposed to cover not only the encapsulation layer 125 and the reflective electrodes 117 but also the upper surfaces of the light emitting diodes 112. Further, since the upper sides of the light emitting diodes 112 are open instead of being covered by the encapsulation layer 125, the transparent electrode 116 can be electrically connected to the p-type electrodes 33 on the light emitting diodes 112, regardless of the locations of the light emitting diodes 112.

The light conversion part 123 includes a phosphor layer 126, a color filter 127 and a protective substrate 128. Although the light conversion part 123 includes the phosphor layer 126, the color filter 127 and the protective substrate 128 in this exemplary embodiment, the light conversion part 123 can be omitted, as needed, and the light conversion part 123 may include one of the phosphor layer 126 and the color filter 127. That is, when blue or UV light emitting diodes are used as the light emitting diodes 112, the light conversion part 123 may include at least one of the phosphor layer 126 and the color filter 127. In addition, in a structure wherein the light emitting diodes 112 include blue light emitting diodes, green light emitting diodes and red light emitting diodes, the light conversion part 123 can be omitted.

The phosphor layer 126 may be disposed on the protective substrate 128 and may include a green phosphor layer 126b, a red phosphor layer 126c and a transparent layer 126e. The green phosphor layer 126b, the red phosphor layer 126c and the transparent layer 126e are alternately arranged to be adjacent each other and separated from each other by a predetermined distance or more. In addition, a blocking layer 126d may be disposed between the green phosphor layer 126b, the red phosphor layer 126c and the transparent layer 126e. Accordingly, the blocking layer 126d can prevent mixture of light by blocking light having entered the green phosphor layer 126b, the red phosphor layer 126c or the transparent layer 126e from entering other phosphor layers.

Although the blue light emitting diodes are illustrated as the light emitting diodes 112 in this exemplary embodiment, the light emitting diodes 112 may emit light having a peak wavelength (for example, 360 nm to 470 nm) in the blue light range or in the near UV range.

Accordingly, the green phosphor layer 126b emits green light through wavelength conversion of blue light emitted from the light emitting diodes 112 and the red phosphor layer 126c emits red light through wavelength conversion of blue light emitted from the light emitting diodes 112. The transparent layer 126e allows blue light emitted from blue light emitting diode to be discharged therethrough without wavelength conversion.

In the structure wherein the light emitting diodes 112 are UV light emitting diodes, a blue phosphor layer 126a may be disposed at the location of the transparent layer 126e instead of the transparent layer 126e. In this structure, UV light emitted from the light emitting diodes 112 is converted into blue light while passing through the blue phosphor layer 126a such that blue light can be discharged outside.

In this exemplary embodiment, the color filter 127 may be interposed between the phosphor layer 126 and the protective substrate 128. The color filter 127 may include a blue light portion 127a, a green light portion 127b, a red light portion 127c, and a light blocking portion 127d. The color filter 127 may be formed in a film shape and can block light having passed through the color filter 127 excluding light of a predetermined wavelength.

The blue light portion 127a of the color filter 127 is disposed on the transparent layer 126e of the phosphor layer 126 and the green light portion 127b of the color filter 12 is disposed on the green phosphor layer 126b of the phosphor layer 126. In addition, the red light portion 127c of the color filter 12 is disposed on the red phosphor layer 126c of the phosphor layer 126. Accordingly, light emitted from the light emitting diodes 112 is subjected to wavelength conversion while passing through the phosphor layer 126, whereby blue light, green light and red light can be separately discharged outside through the color filter 127. By way of example, although blue light emitted from the light emitting diodes 112 is converted into green light through the green phosphor layer 126b, some fraction of blue light can pass through the phosphor layer 126 without wavelength conversion. Blue light having passed through the phosphor layer 126 without wavelength conversion is blocked by the green light portion 127b of the color filter 127 such that only green light can be discharged through the green light portion 127b of the color filter 127.

The protective substrate 128 is disposed to contact the color filter 127 and can protect the color filter 127 from the outside by preventing the color filter 127 from being directly exposed. In this exemplary embodiment, the protective substrate 128 may be formed of a transparent material through which light can pass.

The TFT panel part 130 is coupled to the light emitting part 111 and serves to supply power to the light emitting part 111. To this end, the TFT panel part 130 includes a panel substrate 132 and second connection electrodes 134. The TFT panel part 130 can control power supply to the light emitting diode part 110 to allow only some of the light emitting diodes 112 in the light emitting diode part 110 to emit light and can control the intensity of light emitted from the light emitting diodes 112.

The second connection electrodes 134 are electrically connected to the TFT drive circuit of the panel substrate 132 and to the light emitting diodes 112 or the reflective electrodes 117 of the light emitting diode part 110. That is, the second connection electrodes 134 may be provided in plural and may be separated from each other. Power supplied through the TFT drive circuit can be supplied to each of the light emitting diodes 112 through the second connection electrodes 134 and the reflective electrodes 117. In this exemplary embodiment, the second connection electrodes 134 may be covered by a separate protective layer, which may include, for example, SiNx.

The anisotropic conductive film 150 serves to electrically connect the light emitting diode part 110 to the TFT panel part 130. The anisotropic conductive film 150 may include an adhesive organic insulating material and may contain conductive particles uniformly dispersed therein to achieve electrical connection. The anisotropic conductive film 150 exhibits conductivity in the thickness direction thereof and insulating properties in the plane direction thereof. In addition, the anisotropic conductive film 150 exhibits adhesive properties. With this structure, the anisotropic conductive film 150 can bond the light emitting part 111 to the TFT panel part 130 such that the light emitting part 111 can be electrically connected to the TFT panel part 130 therethrough.

As such, in the structure wherein the light emitting part 111 is coupled to the TFT panel part 130 via the anisotropic conductive film 150, the connection substrate 113 can be electrically connected to the second connection electrodes 134 of the TFT panel part 130 via an electrode connection portion 152.

Figure 16 is sectional views illustrating a process of manufacturing the light emitting diodes of the display apparatus according to the eighth exemplary embodiment of the present disclosure.

Referring to Figure 16, the process of manufacturing the plurality of light emitting diodes 112 will be described.

First, referring to Figure 16A, an n-type semiconductor layer 23, an active layer 25 and a p-type semiconductor layer 27 are sequentially stacked in a predetermined area on a first manufacturing substrate 21a. The n-type semiconductor layer 23 may include an n-type electrode formed on a lower side thereof, as needed. The first manufacturing substrate 21a may be a sapphire substrate, a gallium nitride substrate, a glass substrate, a silicon carbide substrate, a silicon substrate, a metal substrate, a ceramic substrate, or the like.

Referring to Figure 16B, an insulating layer 37, p-type electrodes 33 and inserts 34 may be sequentially formed on the p-type semiconductor layer 27. The insulating layer 37 may be formed to a predetermined thickness on the p-type semiconductor layer 27 and may be subjected to etching to form holes at locations at which light emitting diodes 112 will be formed, such that the p-type semiconductor layer 27 can be exposed through the holes. Then, the p-type electrode 33 is formed on the insulating layer 37 to cover the entirety of the insulating layer 37 while filling the holes formed in the insulating layer 37. As a result, the p-type electrode 33 can be electrically connected to the p-type semiconductor layer 27 through the holes.

After formation of the p-type electrode 33, the insert 34 is formed to a predetermined thickness or more on each p-type electrode 33. The insert 34 may exhibit electrical insulating properties, but is not limited thereto. In this exemplary embodiment, the insert 34 is formed of SiO2. The insert 34 may have a predetermined thickness or more and may be thicker than the p-type electrode 33 formed under the insert 34.

Referring to Figure 16C, a mask 36 is formed on the insert 34. The mask 36 may have a predetermined width and may be disposed on each of the holes formed in the insulating layer 37. That is, the locations of the holes formed in the insulating layer 37 correspond to the light emitting diodes 112 to be formed, and the mask 36 may be formed at the location of the light emitting diodes 112 to be formed. The mask 36 may include a metal.

With the masks 36 disposed on the inserts 34, the p-type electrodes 33, the insulating layer 37, the p-type semiconductor layer 27, the active layer 25 and the n-type semiconductor layer 23 are subjected to etching with reference to the masks 36. As a result, a plurality of light emitting diodes 112 can be formed on the first manufacturing substrate 21a, as shown in Figure 16D. Although the light emitting diodes 112 are illustrating as being perpendicular to the first manufacturing substrate 21a in this exemplary embodiment, the light emitting diodes 112 may be formed to have inclined side surfaces.

In order to transfer the plurality of light emitting diodes 112 to the connection substrate 113, a filler 125a is applied to the light emitting diodes so as to cover all of the light emitting diodes 112, as shown in Figure 16E. Then, as shown in Figure 16F, a second manufacturing substrate 21b is bonded to an upper side of the filler 125a. The second manufacturing substrate 21b may be the same kind of substrate as the first manufacturing substrate 21a or may be a different kind of substrate than the first manufacturing substrate 21a, as needed. After the second manufacturing substrate 21b is coupled to the upper side of the filler 125a, the first manufacturing substrate 21a is removed, as shown in Figure 16G.

Figure 17 is sectional views illustrating a process of manufacturing the light emitting part of the display apparatus according to the eighth exemplary embodiment.

The light emitting part 111 may be manufactured using the plurality of light emitting diodes 112 manufactured by the process shown in Figure 16, and the process of manufacturing the light emitting part will be described with reference to Figure 17.

Referring to Figure 17A, the connection substrate 113 is brought into contact with the plurality of light emitting diodes 112 attached to the second manufacturing substrate 21b. A bonding agent S is deposited to a portion of an upper surface of the connection substrate 113. The bonding agent S may be deposited only to the conductive portions 113a of the connection substrate 113, specifically, only to some conductive portions 113a rather than to all of the conductive portions 113a. Some conductive portions 113a of the connection substrate 113 are electrically connected to the light emitting diodes 112 and the other conductive portions 113a are electrically connected to the reflective electrodes 117, as will be described below. Thus, in order to couple the light emitting diodes 112 to the connection substrate 113, the bonding agent S is applied only to the conductive portions 113a of the connection substrate 113 to which the light emitting diodes 112 will be coupled. In this exemplary embodiment, the bonding agent S may include at least one of In, Sn, AgSn and AuSn.

Among the plurality of light emitting diodes 112 bonded to the second manufacturing substrate 21b, only the light emitting diodes 112 contacting the bonding agent S applied to the conductive portions 113a of the connection substrate 113 are coupled to the connection substrate 113. When the second manufacturing substrate 21b is separated from the connection substrate 113 with some light emitting diodes 112 coupled to the connection substrate 113, the plurality of light emitting diodes 112 can be coupled to the connection substrate 113 so as to be arranged at constant intervals, as shown in Figure 17B. In this exemplary embodiment, one light emitting diode 112 is provided to one subpixel. Alternatively, two or more light emitting diodes 112 may also be provided to one subpixel, as needed.

After the plurality of light emitting diodes 112 is coupled to the connection substrate 113 through the aforementioned process, an encapsulation layer 125 may be formed to cover all of the light emitting diodes 112 and the connection substrate 113, as shown in Figure 17C. The encapsulation layer 125 may include a transparent and electrically insulating material.

Then, referring Figure 17D, the encapsulation layer 125 is subjected to etching to expose the masks 36 and part of the inserts 34. Etching of the encapsulation layer 125 may be performed such that part of the insert 34 protrudes above the encapsulation layer 125.

Then, referring to Figure 17E, first holes H1 are formed by etching the encapsulation layer 125 disposed between the light emitting diodes 112 with reference to the exposed inserts 34. The first holes H1 may be formed to be perpendicular to the upper surface of the connection substrate 113 or may be formed to have an inclined surface, as shown therein. By formation of the first holes H1, the shape of the subpixels on the connection substrate 113 can be determined.

Second holes H2 may be formed on the light emitting diodes 112 simultaneously with or subsequent to formation of the first holes H1. The second holes H2 are formed on the light emitting diodes 112 by removing the masks 36 and the inserts 34 disposed on the light emitting diodes 112. The masks 36 are removed by removing the inserts 34 through etching. For example, the inserts 34 including SiO2 may be removed by etching with HF to form the second holes H2. As a result, the encapsulation layer 125 and the p-type electrodes 33 are not removed and only the inserts 34 are removed by etching, whereby the second holes H2 can be formed on the light emitting diodes 112. In this way, as the second holes H2 are formed by removing the inserts 34 on the light emitting diodes 112, the p-type electrodes 33 can be exposed through the second holes H2.

After the first holes H1 and the second holes H2 are formed as described above, reflective electrodes 117 are formed to fill the first holes H1, as shown in Figure 17F. The reflective electrodes 117 are formed in a shape corresponding to the shape of the first holes H1 and protrude above the first holes H1. As a result, the reflective electrodes 117 can protrude above the upper surface of the encapsulation layer 125. In addition, since the reflective electrodes 117 are formed in the shape corresponding to the shape of the first holes H1, the reflective electrodes 117 may have an inclined side surface.

After formation of the reflective electrodes 117, a transparent electrode 116 is formed to cover the p-type electrodes 33, the encapsulation layer 125 and the reflective electrodes 117, as shown in Figure 17G. The transparent electrode 116 fills the second holes H2 and may fill all steps formed between the encapsulation layer 125 and the reflective electrodes 117. Accordingly, the transparent electrode 116 can be electrically connected to each of the p-type electrodes 33 and the reflective electrodes 117.

After manufacture of the light emitting part 111 is completed, the TFT panel part 130 may be coupled to a lower side of the connection substrate 113 through the anisotropic conductive film 150. The TFT panel part 130 may have a large area and a plurality of light emitting parts 111 may be coupled to one TFT panel part 130.

The light conversion part 123 serving to convert the wavelength of light emitted from the light emitting part 111 or to allow light emitted therefrom and having a certain wavelength to be discharged outside therethrough may be coupled to an upper side of the transparent electrode 116. Like the TFT panel part 130, the light conversion part 123 may also have a large area such that the plurality of light emitting part 111 can be coupled to one light conversion part 123.

Referring to Figure 18, the display apparatus 100 according to the ninth exemplary embodiment includes a light emitting diode part 110, a TFT panel part 130, and an anisotropic conductive film 150. The light emitting diode part 110 includes a light emitting part 111 and a light conversion part 123.

The light emitting part 111 includes light emitting diodes 112, a connection substrate 113, a transparent electrode 116, reflective electrodes 117 and an encapsulation layer 125; and the light conversion part 123 includes a phosphor layer 126, a color filter 127 and a protective substrate 128.

In this exemplary embodiment, referring to FigureFigureFigureFigureFiguremitting diodes 112 include an n-type semiconductor layer 23, an active layer 25, and a p-type semiconductor layer 27. That is, in this exemplary embodiment, the light emitting diodes 112 do not include the insulating layer 37 and the p-type electrode 33, unlike the eighth exemplary embodiment. In this structure, the p-type semiconductor layer 27 of the light emitting diodes 112 may directly adjoin the transparent electrode 116. Thus, power can be supplied to the entirety of the p-type semiconductor layer 27 through the transparent electrode 116.

As such, the light emitting diodes 112 according to the exemplary embodiments are formed to directly contact the connection substrate 113 and the transparent electrode 116, thereby reducing the number of processes in manufacture of the display apparatus, and there is no failure in a process of electrically connecting the transparent electrode 116 to the p-type semiconductor layer 27, although the light emitting diodes 112 are not disposed at accurate locations on the connection substrate 113 as in the eighth exemplary embodiment.

Although some exemplary embodiments have been described herein, it should be understood by those skilled in the art that these embodiments are given by way of illustration only, and that various modifications, variations, and alterations can be made without departing from the spirit and scope of the invention. Therefore, the scope of the present disclosure should be limited only by the accompanying claims and equivalents thereof.

* List of Reference Numerals

100: display apparatus

110: light emitting diode part

111: light emitting part

112: light emitting diode 112a: blue light emitting diode

112b: green light emitting diode 112c: red light emitting diode

21a: first manufacturing substrate 21b: second manufacturing substrate

23: n-type semiconductor layer 25: active layer

27: p-type semiconductor layer 29: light emitting structure

31: n-type electrode 33: p-type electrode

34: insert 36: mask

37: insulating layer

113: connection substrate 113a: conductive portion

113b: insulating portion

114: support substrate 116: transparent electrode

117: reflective electrode 117a: first reflective electrode

117b: second reflective electrode

119: first connection electrode 125: encapsulation layer

125a: filler

123: light conversion portion

126: phosphor layer 126a: blue phosphor layer

126b: green phosphor layer 126c: red phosphor layer

126d: blocking layer 126e: transparent layer

126f: white phosphor layer

127: color filter 127a: blue light portion

127b: green light portion 127c: red light portion

127d: light blocking portion

128: protective substrate

130: TFT panel part 132: panel substrate

134: second connection electrode

150: anisotropic conductive film 152: electrode connection portion

H1, H2: first hole, second hole

S: bonding agent

Claims

A display apparatus comprising:

a light emitting diode part comprising a plurality of light emitting diodes regularly arranged thereon; and

a TFT panel part driving the light emitting diode part,

wherein the light emitting diode part comprises:

a transparent electrode;

the plurality of light emitting diodes regularly arranged on the transparent electrode and electrically connected to the transparent electrode;

a plurality of first reflective electrodes disposed at sides of the plurality of light emitting diodes to surround the plurality of light emitting diodes and electrically connected to the transparent electrode; and

a plurality of second reflective electrodes electrically connected to the plurality of light emitting diodes, respectively, and reflecting light emitted from the plurality of light emitting diodes.
The display apparatus according to claim 1, wherein each of the plurality of light emitting diodes comprises:

a light emitting structure comprising a first conductivity type semiconductor layer, a second conductivity type second conductivity type semiconductor layer, and an active layer interposed between the first and second conductivity type semiconductor layers;

a first electrode disposed to cover the first conductivity type semiconductor layer and electrically connected to the first conductivity type semiconductor layer; and

a second electrode disposed to cover the second conductivity type semiconductor layer and electrically connected to the second conductivity type semiconductor layer,

wherein each of the plurality of light emitting diodes further comprises: an insulating layer interposed between the second conductivity type semiconductor layer and the second electrode and formed therein with a through-hole through which the second conductivity type semiconductor layer is exposed, and the second electrode is electrically connected to the second conductivity type semiconductor layer through the through-hole,

wherein the plurality of second reflective electrodes is electrically connected to the second electrode.
The display apparatus according to claim 1, wherein the light emitting diode part further comprises a color filter disposed on the other surface of the transparent electrode having the plurality of light emitting diodes arranged on one surface thereof, the color filter blocking light emitted from the plurality of light emitting diodes and having a certain wavelength.
The display apparatus according to claim 3, wherein the color filter comprises:

a green light portion allowing only green light to pass therethrough among light emitted from the light emitting diodes; and

a red light portion allowing only red light to pass therethrough among light emitted from the light emitting diodes,

wherein the color filter further comprises a blue light portion allowing only blue light to pass therethrough among light emitted from the light emitting diodes.
The display apparatus according to claim 4, wherein the light emitting diode part further comprises a phosphor layer interposed between the transparent electrode and the color filter and emitting white light through wavelength conversion of light emitted from the plurality of light emitting diodes.
The display apparatus according to claim 4, wherein the light emitting diode part further comprises a phosphor layer disposed to fill spaces between the plurality of light emitting diodes and the plurality of first reflective electrodes and emitting white light through wavelength conversion of light emitted from the plurality of light emitting diodes.
The display apparatus according to claim 1, wherein the light emitting diode part further comprises a phosphor layer disposed on the other surface of the transparent electrode having the plurality of light emitting diodes arranged on one surface thereof, the phosphor layer converting wavelengths of light emitted from the plurality of light emitting diodes.
The display apparatus according to claim 1, wherein the light emitting diode part further comprises a phosphor layer disposed to fill spaces between the plurality of light emitting diodes and the plurality of first reflective electrodes.
The display apparatus according to claim 7 or 8, wherein the light emitting diodes are blue light emitting diodes, and the phosphor layer comprises:

a green phosphor layer emitting green light through wavelength conversion of blue light emitted from the blue light emitting diodes;

a red phosphor layer emitting red light through wavelength conversion of blue light emitted from the blue light emitting diodes; and

a transparent layer allowing light emitted from the blue light emitting diodes to pass therethrough without wavelength conversion.
The display apparatus according to claim 7 or 8, wherein the light emitting diodes are UV light emitting diodes, and the phosphor layer comprises:

a blue phosphor layer emitting blue light through wavelength conversion of UV light emitted from the UV light emitting diodes;

a green phosphor layer emitting green light through wavelength conversion of UV light emitted from the UV light emitting diodes; and

a red phosphor layer emitting red light through wavelength conversion of UV light emitted from the UV light emitting diodes.
The display apparatus according to claim 7 or 8, wherein the phosphor layer emits white light through wavelength conversion of light emitted from the plurality of light emitting diodes.
The display apparatus according to claim 3, wherein the light emitting diode part further comprises a support substrate disposed on a back surface of the color filter with the transparent electrode adjoining one surface of the color filter.
The display apparatus according to claim 7, wherein the light emitting diode part further comprises a support substrate disposed on a back surface of the phosphor layer with the transparent electrode adjoining one surface of the phosphor layer.
The display apparatus according to claim 1, further comprising:

an anisotropic conductive film electrically connecting the light emitting diode part to the TFT panel part.
A display apparatus comprising:

a light emitting part comprising a plurality of light emitting diodes regularly arranged thereon; and

a TFT panel part comprising a plurality of TFTs driving the plurality of light emitting diodes,

wherein the light emitting part comprises:

a substrate;

the plurality of light emitting diodes regularly arranged on the substrate;

an encapsulation layer disposed to surround the plurality of light emitting diodes and formed with grooves exposing upper surfaces of the plurality of light emitting diodes;

a transparent electrode disposed on the plurality of light emitting diodes and electrically connected to the plurality of light emitting diodes through the grooves; and

a plurality of reflective electrodes disposed on the substrate to surround the plurality of light emitting diodes so as to be separated from side surfaces of the plurality of light emitting diodes.
The display apparatus according to claim 15, wherein the transparent electrode is disposed to cover the plurality of light emitting diodes, the encapsulation layer and the plurality of reflective electrodes.
The display apparatus according to claim 15, wherein each of the plurality of light emitting diodes comprises a light emitting structure comprising a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer interposed between the first and second conductivity type semiconductor layers, and the transparent electrode is electrically connected to the second conductivity type semiconductor layer.
The display apparatus according to claim 15, wherein each of the plurality of light emitting diodes comprises:

a light emitting structure comprising a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer interposed between the first and second conductivity type semiconductor layers;

an electrode disposed to cover the second conductivity type semiconductor layer and electrically connected to the second conductivity type semiconductor layer; and

an insulating layer interposed between the second conductivity type semiconductor layer and the electrode and having a through-hole exposing part of the second conductivity type semiconductor layer, and

wherein the electrode is electrically connected to the second conductivity type semiconductor layer through the through-hole.
The display apparatus according to claim 18, wherein the through-hole has a smaller width than an upper surface of the second conductivity type semiconductor layer.
The display apparatus according to claim 18, wherein the electrode and the insulating layer are transparent.
The display apparatus according to claim 15, wherein a height from an upper surface of the substrate to an upper surface of the encapsulation layer is greater than a height from the upper surface of the substrate to upper surfaces of the light emitting diodes.
The display apparatus according to claim 15, wherein the substrate is a connection substrate having a plurality of conductive portions disposed between insulating portions,

wherein the plurality of light emitting diodes is electrically connected to some of the plurality of conductive portions and the plurality of TFTs is electrically connected to the plurality of light emitting diodes through the plurality of conductive portions,

wherein the plurality of reflective electrodes is electrically connected to other conductive portions.
The display apparatus according to claim 15, further comprising:

a light conversion portion converting light emitted from the light emitting part,

wherein the light conversion portion is coupled to one side of the light emitting part.
The display apparatus according to claim 23, wherein the light conversion portion further comprises at least one of a phosphor layer emitting light through wavelength conversion of light emitted from the plurality of light emitting diodes and a color filter blocking light emitted from the plurality of light emitting diodes and having a predetermined wavelength.