Semiconductor light-emitting diode and display device

Abstract

A semiconductor light-emitting device comprises a light-emitting portion having a first region and a second region along the long axis direction, an insulating layer surrounding the side of the first region, and a first electrode surrounding the side of the second region. The thickness of the insulating layer is the same as the thickness of the first electrode. Therefore, when implementing a display, lighting failures can be prevented and brightness deviations eliminated, thereby improving image quality.

Description

Technology Field

[0001] The embodiments relate to semiconductor light-emitting elements and display devices. Background Technology

[0002] Display devices display high-quality images by utilizing self-emissive elements, such as Light Emitting Diodes (LEDs), as the light source for pixels. LEDs exhibit excellent durability even under harsh environmental conditions and are gaining attention as light sources for next-generation display devices due to their long lifespan and high brightness capabilities.

[0003] Recently, research is being conducted to manufacture ultra-small light-emitting diodes using materials with a highly reliable inorganic crystal structure and to utilize them as next-generation pixel light sources by placing them on a panel of a display device (hereinafter referred to as a "display panel").

[0004] These display devices are expanding beyond flat-panel displays into various forms such as flexible displays, foldable displays, stretchable displays, and rollable displays.

[0005] In order to achieve high resolution, pixel sizes are gradually becoming smaller, and since numerous light-emitting elements must be aligned within pixels of such small size, research on the manufacturing of ultra-small light-emitting diodes that are on the micro or nano scale is actively being conducted.

[0006] Improvements in manufacturing processes have enabled the production of not only micro-scale but also nano-scale light-emitting diodes, making it possible to realize ultra-high-resolution displays using these diodes.

[0007] As well as nanoscale light-emitting diodes, they are typically manufactured through growth and etching processes.

[0008] For example, after a semiconductor layer is grown on a wafer, the semiconductor layer is etched using a dry etching process to manufacture a light-emitting diode.

[0009] Plasma is formed for the dry etching process, and the density of this plasma varies depending on the location on the wafer. When the etching process is performed using plasma having different densities depending on the location on the wafer, the degree of etching of the semiconductor layer varies depending on the location on the wafer, so the diameter or length of the manufactured light-emitting diode may vary.

[0010] Furthermore, in order to manufacture nanoscale light-emitting diodes, nanoscale patterns must be formed, but there is a problem in forming such nanoscale patterns. In addition, if the formed nanoscale patterns have different sizes, the diameters of the light-emitting diodes manufactured using these nanoscale patterns as masks may differ.

[0011] A difference in diameter implies a difference in the light-emitting area. Therefore, when implementing a display using light-emitting diodes that differ from this, the brightness of each pixel differs, leading to image quality defects.

[0012] Figure 1 illustrates a manufactured light-emitting diode mounted on a substrate for display implementation.

[0013] When the lengths of the light-emitting diodes manufactured above are different from each other, at least one of the ends of the light-emitting diodes does not come into contact with the wiring electrodes (5, 6) as shown in FIG. 1, causing a lighting failure. As shown in FIG. 1, the light-emitting diode (1) with a normal length is placed on the electrode and lights up, whereas the light-emitting diode (3) with a short length does not come into contact with at least one electrode and does not light up.

[0014] Therefore, when manufacturing nano-sized light-emitting diodes using an etching process as in the past, the diameters and lengths of the manufactured nano-sized light-emitting diodes (3) vary, so there is a problem that mass production is impossible because there are too many pixels that do not light up when implementing a display.

[0015] Meanwhile, conventionally, since the semiconductor layer is etched using dry etching, there is a problem with poor roughness of the etched surface of the semiconductor layer. The problem to be solved

[0016] The embodiments aim to solve the aforementioned problems and other problems.

[0017] Another objective of the embodiment is to provide a semiconductor light-emitting element having the same diameter and / or length (or height).

[0018] In addition, another objective of the embodiment is to provide a semiconductor light-emitting device that does not require the formation of a separate electrode after manufacturing the semiconductor light-emitting device.

[0019] In addition, another objective of the embodiment is to provide a semiconductor light-emitting device that does not require the formation of a separate insulating layer after manufacturing the semiconductor light-emitting device.

[0020] In addition, the embodiment provides a semiconductor light-emitting device that can be manufactured into a desired shape at will.

[0021] In addition, another objective of the embodiment is to provide a display device capable of minimizing lighting failures.

[0022] In addition, another objective of the embodiment is to provide a display device capable of ensuring illumination uniformity of each pixel.

[0023] The technical problems of the embodiments are not limited to those described in this section and include those that can be identified through the description of the invention. means of solving the problem

[0024] According to the first aspect of the embodiment for achieving the above or other purposes, the semiconductor light-emitting element comprises: a light-emitting portion having a first region and a second region along the long axis direction; an insulating layer surrounding the side of the first region; and a first electrode surrounding the side of the second region, wherein the thickness of the insulating layer is the same as the thickness of the first electrode.

[0025] According to a second aspect of the embodiment for achieving the above or other purposes, the display device comprises: a substrate; first and second assembly wirings on the substrate; a plurality of semiconductor light-emitting elements disposed on the first and second assembly wirings and generating different colored light; a first wiring electrode on one side of each of the plurality of semiconductor light-emitting elements; and a second wiring electrode on the other side of each of the plurality of semiconductor light-emitting elements. Effects of the invention

[0026] The effects of the semiconductor light-emitting element and display device according to the embodiment are described as follows.

[0027] According to an embodiment, a semiconductor light-emitting device (150) as shown in FIG. 12 can be manufactured using the process illustrated in FIG. 13 to FIG. 17. That is, a plurality of growth holes (510) are formed on a wafer (501) ( FIG. 15a and FIG. 15b), and a light-emitting part (160) can be grown within the plurality of growth holes (510). Subsequently, an insulating film (503) is removed and the plurality of light-emitting parts are separated from the wafer (501), thereby manufacturing a plurality of semiconductor light-emitting devices (150).

[0028] In the embodiment, since the diameter and / or depth of each of the plurality of growth holes (510) are the same, the diameter and / or length of each of the plurality of light-emitting parts (160) grown in the plurality of growth holes (510) may also be the same.

[0029] In this way, when implementing a display using multiple semiconductor light-emitting elements having the same diameter, the brightness of each pixel is the same, so the brightness difference between pixels can be eliminated and the image quality can be improved. In addition, when implementing a display using multiple semiconductor light-emitting elements having the same length, as shown in FIG. 30, all of the multiple semiconductor light-emitting elements (150B) are electrically connected to the wiring electrodes (330, 340), so lighting failure can be prevented.

[0030] According to an embodiment, a semiconductor light-emitting device (150A) as illustrated in FIGS. 18 and 19 can be manufactured using the process illustrated in FIGS. 20 to 28. That is, after growing a light-emitting portion (160) within a plurality of growth holes (510) on a wafer (501), a portion of the upper side of the insulating film (503) can be removed (Fig. 24). Subsequently, after a metal film is formed, an etching process is performed until all of the metal film on the removed insulating film is removed, thereby forming upper electrodes (156, 157) (Figs. 25 and 26). Subsequently, by performing an etching process using the upper electrodes (156, 157) as a mask to remove the insulating film (503), the insulating film (503) overlapping with the upper electrodes (156, 157) is not removed and can become an insulating layer (155) (Figs. 27 and 28). Afterwards, a lower electrode (158) is formed on the opposite side of the upper electrode (156, 157) in the light-emitting part (160), so that a semiconductor light-emitting device can be manufactured.

[0031] Accordingly, in the manufacturing process of the light-emitting part (160), the upper electrode (156, 157) and the lower electrode (158) as well as the insulating layer (155) are formed, so there is no need to form separate electrodes and an insulating layer after the light-emitting part (160) is manufactured, thus simplifying the process and reducing material costs.

[0032] Further scopes of the applicability of the embodiments will become apparent from the following detailed description. However, since various changes and modifications within the spirit and scope of the embodiments are clearly understood by those skilled in the art, specific embodiments, such as the detailed description and preferred embodiments, should be understood as being given merely as examples. Brief explanation of the drawing

[0033] Figure 1 illustrates a conventional light-emitting diode mounted on a substrate for display implementation. FIG. 2 illustrates a living room of a house in which a display device (100) according to an embodiment is placed. FIG. 3 is a block diagram schematically showing a display device according to an embodiment. Figure 4 is a circuit diagram showing an example of a pixel of Figure 3. Figure 5 is a plan view showing the display panel of Figure 3 in detail. FIG. 6 is an enlarged view of the first panel area of ​​the display device of FIG. 2. Figure 7 is an enlarged view of area A2 in Figure 6. FIG. 8 is a diagram showing an example in which a light-emitting element according to an embodiment is assembled onto a substrate by a self-assembly method. FIGS. 9 and FIGS. 10 are drawings illustrating examples in which a light-emitting element according to an embodiment is transferred to a substrate by a transfer method. FIG. 11 is a cross-sectional view schematically showing the display panel of FIG. 3. FIG. 12 is a cross-sectional view illustrating a semiconductor light-emitting element according to a first embodiment. FIGS. 13 to 17 illustrate a manufacturing process of a semiconductor light-emitting device according to a first embodiment. FIG. 18 is a cross-sectional view illustrating a semiconductor light-emitting element according to a second embodiment. FIG. 19 is a cross-sectional view showing the light-emitting part of FIG. 18 in detail. FIGS. 20 to 28 illustrate a manufacturing process of a semiconductor light-emitting device according to a second embodiment. FIG. 29 is a cross-sectional view illustrating a semiconductor light-emitting element according to a third embodiment. FIG. 30 is a plan view illustrating a display device according to an embodiment. FIG. 31 is a cross-sectional view illustrating a display device according to an embodiment. Specific details for implementing the invention

[0034] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Identical or similar components are assigned the same reference number regardless of drawing symbols, and redundant descriptions thereof will be omitted. The suffixes 'module' and 'part' for components used in the following description are assigned or used interchangeably for the sake of ease of drafting the specification and do not inherently possess distinct meanings or roles. Furthermore, the attached drawings are intended to facilitate an easy understanding of the embodiments disclosed in this specification, and the technical concepts disclosed in this specification are not limited by the attached drawings. Additionally, when an element such as a layer, region, or substrate is referred to as existing 'on' another component, this includes existing directly on the other element or having other intermediate elements existing between them.

[0035] The display devices described in this specification may include mobile phones, smartphones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation systems, slate PCs, tablet PCs, ultra-books, digital TVs, desktop computers, etc. However, the configurations according to the embodiments described in this specification may be applied to devices capable of display, even if they are new product forms developed in the future.

[0036] A light-emitting element according to the following embodiments and a display device including the same will be described.

[0037] FIG. 2 illustrates a living room of a house in which a display device (100) according to an embodiment is placed.

[0038] The display device (100) of the embodiment can display the status of various electronic products such as a washing machine (101), a robot vacuum cleaner (102), and an air purifier (103), communicate with each electronic product based on IoT, and control each electronic product based on user setting data.

[0039] The display device (100) according to the embodiment may include a flexible display fabricated on a thin and flexible substrate. The flexible display can be bent or rolled like paper while maintaining the characteristics of a conventional flat panel display.

[0040] In a flexible display, visual information can be realized by independently controlling the light emission of unit pixels arranged in a matrix form. A unit pixel refers to the smallest unit for realizing a single color. The unit pixels of a flexible display can be realized by a light-emitting element. In the embodiments, the light-emitting element may be a Micro-LED or a Nano-LED, but is not limited thereto.

[0041] FIG. 3 is a block diagram schematically showing a display device according to an embodiment, and FIG. 4 is a circuit diagram showing an example of a pixel of FIG. 3.

[0042] Referring to FIGS. 3 and 4, a display device according to an embodiment may include a display panel (10), a driving circuit (20), a scan driving unit (30), and a power supply circuit (50).

[0043] The display device (100) of the embodiment can drive a light-emitting element in an active matrix (AM) or passive matrix (PM) manner.

[0044] The driving circuit (20) may include a data driving unit (21) and a timing control unit (22).

[0045] The display panel (10) may be rectangular, but is not limited thereto. That is, the display panel (10) may be formed in a circular or elliptical shape. At least one side of the display panel (10) may be formed to be bent at a predetermined curvature.

[0046] The display panel (10) may be divided into a display area (DA) and a non-display area (NDA) placed around the display area (DA). The display area (DA) is an area where pixels (PX) are formed to display an image. The display panel (10) may include data lines (D1~Dm, where m is an integer greater than or equal to 2), scan lines (S1~Sn, where n is an integer greater than or equal to 2) that intersect the data lines (D1~Dm), a high-potential voltage line to which a high-potential voltage is supplied, a low-potential voltage line to which a low-potential voltage is supplied, and pixels (PX) connected to the data lines (D1~Dm) and the scan lines (S1~Sn).

[0047] Each of the pixels (PX) may include a first subpixel (PX1), a second subpixel (PX2), and a third subpixel (PX3). The first subpixel (PX1) may emit first color light of a first main wavelength, the second subpixel (PX2) may emit second color light of a second main wavelength, and the third subpixel (PX3) may emit third color light of a third main wavelength. The first color light may be red light, the second color light may be green light, and the third color light may be blue light, but is not limited thereto. Additionally, FIG. 3 illustrates that each of the pixels (PX) includes three subpixels, but is not limited thereto. That is, each of the pixels (PX) may include four or more subpixels.

[0048] Each of the first subpixel (PX1), the second subpixel (PX2), and the third subpixel (PX3) can be connected to at least one of the data lines (D1~Dm), at least one of the scan lines (S1~Sn), and a high potential voltage line. The first subpixel (PX1) may include light-emitting elements (LDs) as shown in FIG. 4, a plurality of transistors for supplying current to the light-emitting elements (LDs), and at least one capacitor (Cst).

[0049] Although not shown in the drawing, each of the first subpixel (PX1), the second subpixel (PX2), and the third subpixel (PX3) may include only one light-emitting element (LD) and at least one capacitor (Cst).

[0050] Each of the light-emitting elements (LDs) may be a semiconductor light-emitting diode comprising a first electrode, a plurality of conductive semiconductor layers, and a second electrode. Here, the first electrode may be an anode electrode and the second electrode may be a cathode electrode, but is not limited thereto.

[0051] As shown in FIG. 6, a plurality of transistors may include a driving transistor (DT) that supplies current to light-emitting elements (LDs) and a scan transistor (ST) that supplies a data voltage to the gate electrode of the driving transistor (DT). The driving transistor (DT) may include a gate electrode connected to the source electrode of the scan transistor (ST), a source electrode connected to a high-potential voltage line to which a high-potential voltage is applied, and a drain electrode connected to the first electrodes of the light-emitting elements (LDs). The scan transistor (ST) may include a gate electrode connected to a scan line (Sk, where k is an integer satisfying 1 ≤ k ≤ n), a source electrode connected to the gate electrode of the driving transistor (DT), and a drain electrode connected to a data line (Dj, where j is an integer satisfying 1 ≤ j ≤ m).

[0052] A capacitor (Cst) is formed between the gate electrode and the source electrode of the driving transistor (DT). The storage capacitor (Cst) charges the difference between the gate voltage and the source voltage of the driving transistor (DT).

[0053] The driving transistor (DT) and the scan transistor (ST) can be formed as thin film transistors. Additionally, although FIG. 6 describes the driving transistor (DT) and the scan transistor (ST) as being formed as P-type MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), the present invention is not limited thereto. The driving transistor (DT) and the scan transistor (ST) may also be formed as N-type MOSFETs. In this case, the positions of the source electrode and the drain electrode of each of the driving transistor (DT) and the scan transistor (ST) may be changed.

[0054] Additionally, FIG. 4 illustrates that each of the first subpixel (PX1), second subpixel (PX2), and third subpixel (PX3) comprises a 2T1C (2 Transistor - 1 Capacitor) having one driving transistor (DT), one scan transistor (ST), and one capacitor (Cst), but the present invention is not limited thereto. Each of the first subpixel (PX1), second subpixel (PX2), and third subpixel (PX3) may comprise a plurality of scan transistors (ST) and a plurality of capacitors (Cst).

[0055] Since the second subpixel (PX2) and the third subpixel (PX3) can be represented by substantially the same circuit diagram as the first subpixel (PX1), a detailed description of them is omitted.

[0056] The driving circuit (20) outputs signals and voltages for driving the display panel (10). To this end, the driving circuit (20) may include a data driving unit (21) and a timing control unit (22).

[0057] The data driver (21) receives digital video data (DATA) and a source control signal (DCS) from the timing control unit (22). The data driver (21) converts the digital video data (DATA) into analog data voltages according to the source control signal (DCS) and supplies them to the data lines (D1~Dm) of the display panel (10).

[0058] The timing control unit (22) receives digital video data (DATA) and timing signals from a host system. The timing signals may include a vertical sync signal, a horizontal sync signal, a data enable signal, and a dot clock. The host system may be an application processor of a smartphone or tablet PC, a monitor, a system-on-chip of a TV, etc.

[0059] The timing control unit (22) generates control signals to control the operation timing of the data driving unit (21) and the scan driving unit (30). The control signals may include a source control signal (DCS) for controlling the operation timing of the data driving unit (21) and a scan control signal (SCS) for controlling the operation timing of the scan driving unit (30).

[0060] The driving circuit (20) may be placed in a non-display area (NDA) provided on one side of the display panel (10). The driving circuit (20) may be formed as an integrated circuit (IC) and mounted on the display panel (10) using a COG (chip on glass) method, a COP (chip on plastic) method, or an ultrasonic bonding method, but the present invention is not limited thereto. For example, the driving circuit (20) may be mounted on a circuit board (not shown) rather than the display panel (10).

[0061] The data driving unit (21) is mounted on the display panel (10) using a COG (chip on glass) method, a COP (chip on plastic) method, or an ultrasonic bonding method, and the timing control unit (22) can be mounted on the circuit board.

[0062] The scan driver (30) receives a scan control signal (SCS) from the timing control unit (22). The scan driver (30) generates scan signals according to the scan control signal (SCS) and supplies them to the scan lines (S1~Sn) of the display panel (10). The scan driver (30) may be formed in the non-display area (NDA) of the display panel (10) by including a plurality of transistors. Alternatively, the scan driver (30) may be formed as an integrated circuit, in which case it may be mounted on a gate flexible film attached to the other side of the display panel (10).

[0063] The circuit board can be attached to pads provided on one side edge of the display panel (10) using an anisotropic conductive film. As a result, the lead lines of the circuit board can be electrically connected to the pads. The circuit board may be a flexible printed circuit board, a printed circuit board, or a flexible film such as a chip-on-film. The circuit board can be bent toward the bottom of the display panel (10). As a result, one side of the circuit board is attached to one side edge of the display panel (10), and the other side is positioned at the bottom of the display panel (10) and connected to a system board on which a host system is mounted.

[0064] The power supply circuit (50) can generate voltages required for driving the display panel (10) from the main power supplied from the system board and supply them to the display panel (10). For example, the power supply circuit (50) can generate a high potential voltage (VDD) and a low potential voltage (VSS) from the main power to drive the light-emitting elements (LDs) of the display panel (10) and supply them to the high potential voltage line and the low potential voltage line of the display panel (10). In addition, the power supply circuit (50) can generate and supply driving voltages from the main power to drive the driving circuit (20) and the scan driving unit (30).

[0065] FIG. 5 is a plan view showing the display panel of FIG. 3 in detail. For convenience of explanation, FIG. 5 only shows data pads (DP1~DPp, p is an integer greater than or equal to 2), floating pads (FP1, FP2), power pads (PP1, PP2), floating lines (FL1, FL2), low potential voltage line (VSSL), data lines (D1~Dm), first pad electrodes (210), and second pad electrodes (220).

[0066] Referring to FIG. 5, data lines (D1~Dm), first pad electrodes (210), second pad electrodes (220), and pixels (PX) may be arranged in the display area (DA) of the display panel (10).

[0067] The data lines (D1 to Dm) can be extended in a second direction (Y-axis direction). One side of the data lines (D1 to Dm) can be connected to a driving circuit (20 in FIG. 5). As a result, data voltages of the driving circuit (20) can be applied to the data lines (D1 to Dm).

[0068] The first pad electrodes (210) may be spaced apart at a predetermined interval in the first direction (X-axis direction). As a result, the first pad electrodes (210) may not overlap with the data lines (D1 to Dm). Among the first pad electrodes (210), the first pad electrodes (210) positioned at the right edge of the display area (DA) may be connected to the first floating line (FL1) in the non-display area (NDA). Among the first pad electrodes (210), the first pad electrodes (210) positioned at the left edge of the display area (DA) may be connected to the second floating line (FL2) in the non-display area (NDA).

[0069] Each of the second pad electrodes (220) can be extended in the first direction (X-axis direction). As a result, the second pad electrodes (220) can overlap with the data lines (D1 to Dm). Additionally, the second pad electrodes (220) can be connected to the low potential voltage line (VSSL) in the non-display area (NDA). As a result, the low potential voltage of the low potential voltage line (VSSL) can be applied to the second pad electrodes (220).

[0070] A pad section (PA), a driving circuit (20), a first floating line (FL1), a second floating line (FL2), and a low potential voltage line (VSSL) may be disposed in the non-display area (NDA) of the display panel (10). The pad section (PA) may include data pads (DP1~DPp), floating pads (FP1, FP2), and power pads (PP1, PP2).

[0071] The pad section (PA) may be positioned on one side edge of the display panel (10), for example, on the lower edge. Data pads (DP1 to DPp), floating pads (FP1, FP2), and power pads (PP1, PP2) may be positioned side by side in the pad section (PA) in a first direction (X-axis direction).

[0072] A circuit board can be attached to the data pads (DP1~DPp), floating pads (FP1, FP2), and power pads (PP1, PP2) using an anisotropic conductive film. As a result, the circuit board and the data pads (DP1~DPp), floating pads (FP1, FP2), and power pads (PP1, PP2) can be electrically connected.

[0073] The driving circuit (20) can be connected to data pads (DP1~DPp) via link lines. The driving circuit (20) can receive digital video data (DATA) and timing signals through the data pads (DP1~DPp). The driving circuit (20) can convert the digital video data (DATA) into analog data voltages and supply them to the data lines (D1~Dm) of the display panel (10).

[0074] The low potential voltage line (VSSL) can be connected to the first power pad (PP1) and the second power pad (PP2) of the pad section (PA). The low potential voltage line (VSSL) can be extended in the second direction (Y-axis direction) from the left outer and right outer non-display area (NDA) of the display area (DA). The low potential voltage line (VSSL) can be connected to the second pad electrode (220). As a result, the low potential voltage of the power supply circuit (50) can be applied to the second pad electrode (220) through the circuit board, the first power pad (PP1), the second power pad (PP2), and the low potential voltage line (VSSL).

[0075] The first floating line (FL1) can be connected to the first floating pad (FP1) of the pad portion (PA). The first floating line (FL1) can be extended in the second direction (Y-axis direction) from the left outer and right outer non-display area (NDA) of the display area (DA). The first floating pad (FP1) and the first floating line (FL1) may be dummy pads and dummy lines to which no voltage is applied.

[0076] The second floating line (FL2) can be connected to the second floating pad (FP2) of the pad portion (PA). The first floating line (FL1) can be extended in the second direction (Y-axis direction) from the left outer and right outer non-display area (NDA) of the display area (DA). The second floating pad (FP2) and the second floating line (FL2) may be dummy pads and dummy lines to which no voltage is applied.

[0077] Meanwhile, since the light-emitting elements (LDs of FIG. 6) have a very small size, it is very difficult to mount them on the first sub-pixel (PX1), second sub-pixel (PX2), and third sub-pixel (PX3) of each pixel (PX).

[0078] To resolve this problem, an alignment method using dielectrophoresis has been proposed.

[0079] That is, during the manufacturing process of the display panel (10), an electric field can be formed in each of the first sub-pixel (PX1), second sub-pixel (PX2), and third sub-pixel (PX3) of the pixels (PX) to align the light-emitting elements (150 in FIG. 6). Specifically, during the manufacturing process, the light-emitting elements (150) can be aligned to each of the first sub-pixel (PX1), second sub-pixel (PX2), and third sub-pixel (PX3) by applying a dielectrophoretic force to the light-emitting elements (150) using a dielectrophoretic method.

[0080] However, during the manufacturing process, it is difficult to drive the thin-film transistors to apply a ground voltage to the first pad electrodes (210).

[0081] Accordingly, in the finished display device, the first pad electrodes (210) are spaced apart at a predetermined interval in the first direction (X-axis direction), but during the manufacturing process, the first pad electrodes (210) are not disconnected in the first direction (X-axis direction) and can be extended and arranged in a long manner.

[0082] As a result, the first pad electrodes (210) can be connected to the first floating line (FL1) and the second floating line (FL2) during the manufacturing process. Therefore, the first pad electrodes (210) can receive a ground voltage through the first floating line (FL1) and the second floating line (FL2). Thus, after aligning the light-emitting elements (150) using a dielectrophoretic method during the manufacturing process, the first pad electrodes (210) can be disconnected so that the first pad electrodes (210) are spaced apart at a predetermined interval in the first direction (X-axis direction).

[0083] Meanwhile, the first floating line (FL1) and the second floating line (FL2) are lines for applying a ground voltage during the manufacturing process, and no voltage may be applied to the finished display device. Alternatively, a ground voltage may be applied to the first floating line (FL1) and the second floating line (FL2) for electrostatic discharge prevention or for driving the light-emitting element (150) in the finished display device.

[0084] FIG. 6 is an enlarged view of the first panel area of ​​the display device of FIG. 2.

[0085] According to FIG. 6, the display device (100) of the embodiment can be manufactured by mechanically and electrically connecting a plurality of panel regions, such as a first panel region (A1), by tiling.

[0086] The first panel area (A1) may include a plurality of light-emitting elements (150) arranged per unit pixel (PX in FIG. 5).

[0087] For example, a unit pixel (PX) may include a first sub-pixel (PX1), a second sub-pixel (PX2), and a third sub-pixel (PX3). For example, a plurality of red light-emitting elements (150R) may be placed in the first sub-pixel (PX1), a plurality of green light-emitting elements (150G) may be placed in the second sub-pixel (PX2), and a plurality of blue light-emitting elements (150B) may be placed in the third sub-pixel (PX3). The unit pixel (PX) may further include a fourth sub-pixel in which no light-emitting elements are placed, but is not limited thereto.

[0088] Figure 7 is an enlarged view of area A2 in Figure 6.

[0089] Referring to FIG. 7, the display device (100) of the embodiment may include a substrate (200), wiring electrodes (201, 202), an insulating layer (206), and a plurality of light-emitting elements (150). More components than these may be included.

[0090] The wiring electrode may include a first wiring electrode (201) and a second wiring electrode (202) spaced apart from each other. The first wiring electrode (201) and the second wiring electrode (202) may be provided to generate a dielectrophoretic force to assemble a light-emitting element (150).

[0091] The light-emitting element (150) may include a red light-emitting element (150), a green light-emitting element (150G), and a blue light-emitting element (150B0) to form a unit pixel (sub-pixel), but is not limited thereto, and may also implement red and green by providing a red phosphor and a green phosphor, etc.

[0092] The substrate (200) may be formed of glass or polyimide. Additionally, the substrate (200) may include flexible materials such as PEN (Polyethylene Naphthalate) or PET (Polyethylene Terephthalate). Furthermore, the substrate (200) may be a transparent material, but is not limited thereto.

[0093] The insulating layer (206) may include a material with insulating and flexible properties such as polyimide, PEN, PET, etc., and may be formed integrally with the substrate (200) to form a single substrate.

[0094] The insulating layer (206) may be a conductive adhesive layer having adhesiveness and conductivity, and the conductive adhesive layer may be flexible to enable the flexible function of the display device. For example, the insulating layer (206) may be an anisotropy conductive film (ACF), an anisotropy conductive medium, a solution containing conductive particles, etc., and a conductive adhesive layer. The conductive adhesive layer may be a layer that is electrically conductive in the direction perpendicular to the thickness, but electrically insulating in the direction horizontal to the thickness.

[0095] The insulating layer (206) may include an assembly hole (203) into which a light-emitting element (150) is inserted. Accordingly, when self-assembling, the light-emitting element (150) can be easily inserted into the assembly hole (203) of the insulating layer (206). The assembly hole (203) may be called an insertion hole, a fixing hole, an alignment hole, etc.

[0096] Meanwhile, the method of mounting the light-emitting element (150) on the substrate (200) may include, for example, a self-assembly method (Fig. 8) and a transfer method (Figs. 9 and 10).

[0097] FIG. 8 is a diagram showing an example in which a light-emitting element according to an embodiment is assembled onto a substrate by a self-assembly method.

[0098] A self-assembly method of a light-emitting element is explained with reference to FIGS. 7 and FIGS. 8.

[0099] The substrate (200) may be a panel substrate of a display device. In the following description, the substrate (200) is described as being a panel substrate of a display device, but the embodiment is not limited thereto.

[0100] The substrate (200) may be formed of glass or polyimide. Additionally, the substrate (200) may include flexible materials such as PEN (Polyethylene Naphthalate) or PET (Polyethylene Terephthalate). Furthermore, the substrate (200) may be a transparent material, but is not limited thereto.

[0101] Referring to FIG. 8, a light-emitting element (150) can be introduced into a chamber (1300) filled with a fluid (1200). The fluid (1200) may be water, such as ultrapure water, but is not limited thereto. The chamber may be called a water tank, a container, a vessel, etc.

[0102] After this, the substrate (200) can be placed on the chamber (1300). According to an embodiment, the substrate (200) may be introduced into the chamber (1300).

[0103] As shown in FIG. 7, a pair of wiring electrodes (201, 202) corresponding to each of the light-emitting elements (150) to be assembled may be disposed on the substrate (200).

[0104] The wiring electrodes (201, 202) may be formed of a transparent electrode (ITO) or may include a metallic material with excellent electrical conductivity. For example, the wiring electrodes (201, 202) may be formed of at least one of titanium (Ti), chromium (Cr), nickel (Ni), aluminum (Al), platinum (Pt), gold (Au), tungsten (W), and molybdenum (Mo), or an alloy thereof.

[0105] An electric field is formed between the wiring electrodes (201, 202) by an externally supplied voltage, and a dielectrophoretic force can be formed between the wiring electrodes (201, 202) by this electric field. By this dielectrophoretic force, a light-emitting element (150) can be fixed to an assembly hole (203) on the substrate (200).

[0106] The gap between the wiring electrodes (201, 202) is formed to be smaller than the width of the light-emitting element (150) and the width of the assembly hole (203), so that the assembly position of the light-emitting element (150) using an electric field can be fixed more precisely.

[0107] An insulating layer (206) is formed on the wiring electrodes (201, 202) to protect the wiring electrodes (201, 202) from the fluid (1200) and prevent leakage of current flowing through the wiring electrodes (201, 202). The insulating layer (206) may be formed as a single layer or multiple layers of an inorganic insulator such as silica or alumina, or an organic insulator.

[0108] Additionally, the insulating layer (206) may include a material with insulating and flexible properties such as polyimide, PEN, PET, etc., and may be formed integrally with the substrate (200) to form a single substrate.

[0109] The insulating layer (206) may be an insulating layer that is adhesive or a conductive adhesive layer that is conductive. The insulating layer (206) may be flexible so that it can enable the flexible function of the display device.

[0110] The insulating layer (206) has a partition, and an assembly hole (203) can be formed by this partition. For example, when forming the substrate (200), a portion of the insulating layer (206) is removed so that each of the light-emitting elements (150) can be assembled in the assembly hole (203) of the insulating layer (206).

[0111] An assembly hole (203) is formed in the substrate (200) to which light-emitting elements (150) are joined, and the surface on which the assembly hole (203) is formed can come into contact with a fluid (1200). The assembly hole (203) can guide the precise assembly position of the light-emitting elements (150).

[0112] Meanwhile, the assembly hole (203) may have a shape and size corresponding to the shape of the light-emitting element (150) to be assembled at the corresponding location. Accordingly, it is possible to prevent other light-emitting elements from being assembled in the assembly hole (203) or multiple light-emitting elements from being assembled.

[0113] Referring again to FIG. 8, after the substrate (200) is placed, an assembly device (1100) including a magnetic material can move along the substrate (200). For example, a magnet or an electromagnet may be used as the magnetic material. The assembly device (1100) can move while in contact with the substrate (200) to maximize the area where the magnetic field is applied within the fluid (1200). According to an embodiment, the assembly device (1100) may include a plurality of magnetic materials or a magnetic material of a size corresponding to that of the substrate (200). In this case, the movement distance of the assembly device (1100) may be limited to within a predetermined range.

[0114] Due to the magnetic field generated by the assembly device (1100), the light-emitting element (150) inside the chamber (1300) can move toward the assembly device (1100).

[0115] While moving toward the assembly device (1100), the light-emitting element (150) can enter the assembly hole (203) and come into contact with the substrate (200).

[0116] At this time, the light-emitting element (150) in contact with the substrate (200) can be prevented from being dislodged by the movement of the assembly device (1100) by the electric field applied by the wiring electrodes (201, 202) formed on the substrate (200).

[0117] That is, by the self-assembly method using the electromagnetic field described above, the time required for each of the light-emitting elements (150) to be assembled onto the substrate (200) can be drastically reduced, so a large-area high-pixel display can be implemented more quickly and economically.

[0118] A predetermined solder layer (225) may be further formed between the light-emitting element (150) assembled on the assembly hole (203) of the substrate (200) and the second pad electrode (222) to improve the bonding strength of the light-emitting element (150).

[0119] Afterwards, the first pad electrode (221) can be connected to the light-emitting element (150) to apply power.

[0120] Next, a molding layer (230) may be formed on the partition wall (200S) and assembly hole (203) of the substrate (200). The molding layer (230) may be a transparent resin or a resin containing a reflective material or a scattering material.

[0121] FIGS. 9 and FIGS. 10 are drawings illustrating examples in which a light-emitting element according to an embodiment is transferred to a substrate by a transfer method.

[0122] As illustrated in FIG. 9, a plurality of light-emitting elements (150) may be attached to a substrate (1500). For example, the substrate (1500) may be a donor substrate serving as an intermediate medium for mounting light-emitting elements (150) on a display substrate. In this case, a plurality of light-emitting elements (150) manufactured on a wafer may be attached to the substrate (1500), and the plurality of light-emitting elements (150) attached to the substrate (1500) may be transferred onto the display substrate.

[0123] Although the substrate (1500) is described below as a donor substrate, the substrate (1500) may be a display substrate for which a plurality of light-emitting elements (150) are transferred directly without passing through the donor substrate.

[0124] As illustrated in FIG. 9, after the substrate (1500) is positioned on the display substrate (200), an alignment process can be performed so that each of the plurality of light-emitting elements (150) on the substrate (1500) corresponds to each pixel of the display substrate (200).

[0125] Afterwards, by applying pressure to the substrate (1500) (or the display substrate (200)), a plurality of light-emitting elements (150) on the substrate (1500) can be transferred to each pixel on the display substrate (200) as shown in FIG. 10.

[0126] Afterwards, through a subsequent process, a plurality of light-emitting elements (150) are attached to a display substrate (200) and the plurality of light-emitting elements (150) are electrically connected to a power source, so that the plurality of light-emitting elements (150) emit light and an image can be displayed.

[0127] Meanwhile, in the display device according to the embodiment, an image can be displayed using a light-emitting element. The light-emitting element of the embodiment is a self-emissive element that emits light by itself when electricity is applied, and may be a semiconductor light-emitting element. Since the light-emitting element of the embodiment is made of an inorganic semiconductor material, it is resistant to degradation and has a semi-permanent lifespan, so it provides stable light, which can contribute to the display device realizing high-quality and high-definition images.

[0128] For example, a display device may use a light-emitting element as a light source and provide a color generating unit on the light-emitting element to display an image by means of the color generating unit (Fig. 11).

[0129] Although not illustrated, the display device may also display projections through a display panel in which each of the multiple light-emitting elements generating different colored light is arranged in a pixel.

[0130] FIG. 11 is a cross-sectional view schematically showing the display panel of FIG. 5.

[0131] Referring to FIG. 11, the display panel (10) of the embodiment may include a first substrate (40), a light-emitting unit (41), a color-generating unit (42), and a second substrate (46). The display panel (10) of the embodiment may include more configurations than those shown, but is not limited thereto. The first substrate (40) may be the substrate (200) shown in FIG. 9.

[0132] Although not illustrated, at least one insulating layer may be disposed between the first substrate (40) and the light-emitting part (41), between the light-emitting part (41) and the color generating part (42), and / or between the color generating part (42) and the second substrate (46), but is not limited thereto.

[0133] The first substrate (40) can support a light-emitting part (41), a color-generating part (42), and a second substrate (46). The first substrate (40) may be provided with various elements as described above, such as data lines (D1~Dm, where m is an integer greater than or equal to 2), scan lines (S1~Sn), high potential voltage lines and low potential voltage lines as shown in FIG. 5, a plurality of transistors (ST, DT) and at least one capacitor (Cst) as shown in FIG. 6, and a first pad electrode (210) and a second pad electrode (220) as shown in FIG. 7.

[0134] The first substrate (40) may be formed of glass or a flexible material, but is not limited thereto.

[0135] The light-emitting unit (41) can provide light to the color-generating unit (42). The light-emitting unit (41) may include a plurality of light sources that emit light by themselves when electricity is applied. For example, the light source may include a light-emitting element (150 in FIG. 6).

[0136] For example, a plurality of light-emitting elements (150) are arranged separately for each subpixel of the pixel and can emit light independently by controlling each individual subpixel.

[0137] As another example, a plurality of light-emitting elements (150) are arranged regardless of pixel division and can emit light simultaneously in all subpixels.

[0138] The light-emitting element (150) of the embodiment may emit blue light, but is not limited thereto. For example, the light-emitting element (150) of the embodiment may emit white light or purple light.

[0139] Meanwhile, the light-emitting element (150) may emit red light, green light, and blue light for each subpixel. To this end, for example, a red light-emitting element that emits red light may be placed in the first subpixel, i.e., the red subpixel, a green light-emitting element that emits green light may be placed in the second subpixel, i.e., the green subpixel, and a blue light-emitting element that emits blue light may be placed in the third subpixel, i.e., the blue subpixel.

[0140] For example, each of the red light-emitting device, the green light-emitting device, and the blue light-emitting device may include a Group II-IV compound or a Group III-V compound, but is not limited thereto. For example, the Group III-V compound is a binary compound selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof; a ternary compound selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlInP, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, and mixtures thereof; and may be selected from the group consisting of four-element compounds selected from the group consisting of AlGaInP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and mixtures thereof.

[0141] The color generating unit (42) can generate a color light different from the light provided by the light emitting unit (41).

[0142] For example, the color generating unit (42) may include a first color generating unit (43), a second color generating unit (44), and a third color generating unit (45). The first color generating unit (43) corresponds to a first sub-pixel (PX1) of the pixel, the second color generating unit (44) corresponds to a second sub-pixel (PX2) of the pixel, and the third color generating unit (45) corresponds to a third sub-pixel (PX3) of the pixel.

[0143] The first color generating unit (43) can generate a first color light based on the light provided by the light-emitting unit (41), the second color generating unit (44) can generate a second color light based on the light provided by the light-emitting unit (41), and the third color generating unit (45) can generate a third color light based on the light provided by the light-emitting unit (41). For example, the first color generating unit (43) can output the blue light of the light-emitting unit (41) as red light, the second color generating unit (44) can output the blue light of the light-emitting unit (41) as green light, and the third color generating unit (45) can output the blue light of the light-emitting unit (41) as is.

[0144] For example, the first color generating unit (43) may include a first color filter, the second color generating unit (44) may include a second color filter, and the third color generating unit (45) may include a third color filter.

[0145] The first color filter, the second color filter, and the third color filter can be formed of a transparent material through which light can pass.

[0146] For example, at least one of the first color filter, the second color filter, and the third color filter may include a quantum dot.

[0147] The quantum dots of the examples can be selected from group II-IV compounds, group III-V compounds, group IV-VI compounds, group IV elements, group IV compounds, and combinations thereof.

[0148] Group II-VI compounds are diatomic compounds selected from the group consisting of CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, and mixtures thereof; ternary compounds selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, and mixtures thereof; and may be selected from the group consisting of four-element compounds selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe and mixtures thereof.

[0149] III-V group compounds may be selected from the group consisting of diatomic compounds selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof; ternary compounds selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlInP, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, and mixtures thereof; and quaternary compounds selected from the group consisting of AlGaInP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and mixtures thereof.

[0150] Group IV-VI compounds may be selected from the group consisting of diatomic compounds selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe and mixtures thereof; ternary compounds selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe and mixtures thereof; and quaternary compounds selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe and mixtures thereof.

[0151] Group IV elements may be selected from the group consisting of Si, Ge, and mixtures thereof. Group IV compounds may be diatomic compounds selected from the group consisting of SiC, SiGe, and mixtures thereof.

[0152] These quantum dots can have a full width of half maximum (FWHM) of the emission wavelength spectrum of approximately 45 nm or less, and light emitted through the quantum dots can be emitted in all directions. Accordingly, the viewing angle of the light-emitting display device can be improved.

[0153] Meanwhile, quantum dots can have the form of spherical, pyramidal, multi-arm, or cubic nanoparticles, nanotubes, nanowires, nanofibers, nanoplate-like particles, etc., but are not limited thereto.

[0154] For example, when the light-emitting element (150) emits blue light, the first color filter may include red quantum dots, and the second color filter may include green quantum dots. The third color filter may not include quantum dots, but is not limited thereto. For example, blue light from the light-emitting element (150) may be absorbed by the first color filter, and the absorbed blue light may be wavelength-shifted by the red quantum dots to output red light. For example, blue light from the light-emitting element (150) may be absorbed by the second color filter, and the absorbed blue light may be wavelength-shifted by the green quantum dots to output green light. For example, blue light from the light-emitting element may be absorbed by the third color filter, and the absorbed blue light may be emitted as is.

[0155] Meanwhile, when the light-emitting element (150) is white light, the first color filter and the second color filter, as well as the third color filter, may also include quantum dots. That is, the white light of the light-emitting element (150) can be wavelength-shifted into blue light by the quantum dots included in the third color filter.

[0156] For example, at least one of the first color filter, the second color filter, and the third color filter may include a phosphor. For example, some of the first color filter, the second color filter, and the third color filter may include quantum dots, and others may include a phosphor. For example, each of the first color filter and the second color filter may include a phosphor and a quantum dot. For example, at least one of the first color filter, the second color filter, and the third color filter may include scattering particles. Since blue light incident on each of the first color filter, the second color filter, and the third color filter is scattered by the scattering particles and the scattered blue light is color-shifted by the corresponding quantum dots, the light output efficiency may be improved.

[0157] As another example, the first color generating unit (43) may include a first color conversion layer and a first color filter. The second color generating unit (44) may include a second color conversion unit and a second color filter. The third color generating unit (45) may include a third color conversion layer and a third color filter. Each of the first color conversion layer, the second color conversion layer, and the third color conversion layer may be disposed adjacent to the light-emitting unit (41). The first color filter, the second color filter, and the third color filter may be disposed adjacent to the second substrate (46).

[0158] For example, a first color filter may be placed between the first color conversion layer and the second substrate (46). For example, a second color filter may be placed between the second color conversion layer and the second substrate (46). For example, a third color filter may be placed between the third color conversion layer and the second substrate (46).

[0159] For example, the first color filter may be in contact with the upper surface of the first color conversion layer and have the same size as the first color conversion layer, but is not limited thereto. For example, the second color filter may be in contact with the upper surface of the second color conversion layer and have the same size as the second color conversion layer, but is not limited thereto. For example, the third color filter may be in contact with the upper surface of the third color conversion layer and have the same size as the third color conversion layer, but is not limited thereto.

[0160] For example, the first color conversion layer may include red quantum dots, and the second color conversion layer may include green quantum dots. The third color conversion layer may not include quantum dots. For example, the first color filter may include a red-based material that selectively transmits red light converted in the first color conversion layer, the second color filter may include a green-based material that selectively transmits green light converted in the second color conversion layer, and the third color filter may include a blue-based material that selectively transmits blue light transmitted as is from the third color conversion layer.

[0161] Meanwhile, when the light-emitting element (150) is white light, the first color conversion layer and the second color conversion layer, as well as the third color conversion layer, may also include quantum dots. That is, the white light of the light-emitting element (150) can be wavelength-shifted into blue light by the quantum dots included in the third color filter.

[0162] Referring again to FIG. 11, the second substrate (46) is placed on the color generating unit (42) to protect the color generating unit (42). The second substrate (46) may be formed of glass, but is not limited thereto.

[0163] The second substrate (46) can be called a cover window, cover glass, etc.

[0164] The second substrate (46) may be formed of glass or a flexible material, but is not limited thereto.

[0165] The embodiment provides a plurality of semiconductor light-emitting elements having the same size. That is, the size of a plurality of semiconductor light-emitting elements manufactured on a wafer may be the same. Here, size may mean at least one of diameter and / or length (or height). The semiconductor light-emitting element of the embodiment may have a minor axis and a major axis. The minor axis may be the diameter direction of the semiconductor light-emitting element, and the major axis direction may be the length direction of the semiconductor light-emitting element. Therefore, in the semiconductor light-emitting element of the embodiment, the length may be greater than the diameter. The semiconductor light-emitting element of the embodiment may have a rod shape, but is not limited thereto. The semiconductor light-emitting element of the embodiment may be a nanoscale semiconductor light-emitting element, but is not limited thereto.

[0166] The semiconductor light-emitting device of the embodiment can be manufactured by growing in a growth hole that is pre-formed in the shape of a rod. The growth hole may correspond to the size of the semiconductor light-emitting device. That is, the growth hole may have a diameter corresponding to the diameter of the semiconductor light-emitting device and a depth corresponding to the length of the semiconductor light-emitting device. A semiconductor light-emitting device can be manufactured by growing a plurality of semiconductor layers in the growth hole through a growth process.

[0167] Multiple growth holes are provided on a wafer, and multiple semiconductor layers are sequentially grown in these multiple growth holes, thereby allowing multiple semiconductor light-emitting devices to be manufactured simultaneously. At this time, the multiple growth holes may have the same diameter and depth. Accordingly, multiple semiconductor light-emitting devices manufactured in multiple growth holes having the same diameter and depth may have the same size.

[0168] Conventionally, multiple semiconductor layers were sequentially grown on a wafer via a deposition process, followed by the fabrication of multiple semiconductor light-emitting devices through an etching process. In such cases, not only did the plasma density vary depending on the position on the wafer during the etching process, but due to the characteristics of the etching process, etching was performed in both vertical and horizontal directions. Consequently, the upper diameter of the multiple semiconductor light-emitting devices was smaller than the lower diameter, and the diameter of the active layer of each device differed from one another depending on the wafer position. Due to these differing active layer diameters, the light efficiency and light output of each semiconductor light-emitting device varied. Therefore, when implementing a display using these multiple semiconductor light-emitting devices, a difference in brightness occurred between pixels, which in turn led to a problem of degraded image quality.

[0169] However, in the embodiments, a plurality of growth holes having the same depth and diameter are provided on a wafer in advance, and a plurality of semiconductor layers are grown in these plurality of growth holes using a deposition process, thereby manufacturing a plurality of semiconductor light-emitting devices having a shape corresponding to each of the growth holes. The plurality of semiconductor light-emitting devices manufactured above may have the same diameter and / or length regardless of the position on the wafer. The diameter of the semiconductor light-emitting device may be the same as the diameter of the growth hole. The length of the semiconductor light-emitting device may be the same as the depth of the growth hole.

[0170] Therefore, in the embodiments, since multiple semiconductor layers are grown in the growth holes even if the wafer densities differ during the plasma process, the semiconductor light-emitting devices obtained from each of the multiple growth holes can have the same diameter and / or length.

[0171] Here, the length may be a length such that both ends of the semiconductor light-emitting element can electrically contact each assembly line spaced apart from each other on the display substrate. If the length of the semiconductor light-emitting element is reduced, the semiconductor light-emitting element with reduced length does not electrically contact one of the assembly lines and therefore does not emit light. However, as in the example, since the length of each semiconductor light-emitting element manufactured on the wafer has a length such that it can electrically contact all assembly lines, lighting failures can be minimized.

[0172] Meanwhile, in the embodiment, since the diameters of the plurality of semiconductor light-emitting elements manufactured in the plurality of growth holes of the wafer are all the same, the same light efficiency or light output can be obtained. Therefore, when implementing a display using the plurality of semiconductor light-emitting elements manufactured on the wafer, there is no difference in brightness between each pixel, so the image quality can be improved. At least one semiconductor light-emitting element may be provided in each pixel.

[0173] Meanwhile, the inner surface of the growth hole may have a plane perpendicular to the bottom surface. Accordingly, the side of the semiconductor light-emitting device manufactured within the growth hole may have a plane perpendicular to the bottom or top surface of the semiconductor light-emitting device.

[0174] The inner surface of the growth hole can have a smooth plane, that is, a plane with minimal roughness. Therefore, since the side of the semiconductor light-emitting device manufactured within the growth hole has a smooth plane, the roughness can be improved.

[0175] Meanwhile, conventionally, multiple semiconductor layers are grown through a growth process, and individual semiconductor light-emitting devices are manufactured through a dry etching process. During the dry etching process, the plasma density varies depending on the location on the wafer, and the nanoscale patterns formed for the etching process differ from one another, so the sizes (diameter and / or length) of multiple semiconductor light-emitting devices manufactured on the wafer differ from one another. Therefore, when multiple semiconductor light-emitting devices having different sizes are mounted on a display substrate, there is a problem in that the semiconductor light-emitting device that does not come into contact with the electrode on the display substrate does not light up.

[0176] According to the embodiment, since a plurality of semiconductor light-emitting elements manufactured on a wafer have the same size, when such a plurality of semiconductor light-emitting elements are mounted on a display substrate (301 in FIG. 31), lighting can be achieved at all pixels, thereby preventing lighting failures.

[0177] In addition, according to the embodiment, since a plurality of semiconductor light-emitting elements have the same size, each of the plurality of semiconductor light-emitting elements can have the same brightness. Therefore, when a plurality of semiconductor light-emitting elements are mounted on a display substrate (301), uniform brightness is obtained in all pixels, and image quality can be improved.

[0178] Meanwhile, conventionally, a semiconductor light-emitting device is manufactured through a growth process and an etching process, and then an electrode is formed through a separate process, followed by the formation of an insulating layer through a separate process. According to the embodiment, an electrode or an insulating layer is formed during the manufacturing process of the semiconductor light-emitting device, so there is no need to form a separate electrode or insulating layer after the semiconductor light-emitting device is manufactured, which can drastically shorten the manufacturing process.

[0179] A semiconductor light-emitting element and a display device according to an embodiment will be described in detail below with reference to FIGS. 12 to 30.

[0180] [Semiconductor light-emitting device]

[0181] FIG. 12 is a cross-sectional view illustrating a semiconductor light-emitting element according to a first embodiment.

[0182] Referring to FIG. 12, a semiconductor light-emitting device (150) according to a first embodiment may include a first conductivity semiconductor layer (151), an active layer (152), and a second conductivity semiconductor layer (153). The semiconductor light-emitting device (150) according to a first embodiment may include more components than those described above. For example, the first conductivity semiconductor layer (151) may include at least one layer. For example, the active layer (152) may include at least one layer. For example, the second conductivity semiconductor layer (153) may include at least one layer.

[0183] The first conductivity type semiconductor layer (151), the active layer (152), and the second conductivity type semiconductor layer (153) can form a light-emitting part (160). The light-emitting part (160) may have a cylindrical shape, but is not limited thereto.

[0184] The semiconductor light-emitting element (150) according to the first embodiment can generate light of a specific color. The semiconductor light-emitting element (150) according to the first embodiment may be one of ultraviolet light, white light, blue light, green light, red light, and infrared light.

[0185] Meanwhile, the first conductivity type semiconductor layer (151), the active layer (152), and the second conductivity type semiconductor layer (153) can be grown sequentially, for example, using MOCVD equipment.

[0186] Conventionally, a first conductivity semiconductor layer (151), an active layer (152), and a second conductivity semiconductor layer (153) are sequentially grown on a wafer, and then the second conductivity semiconductor layer (153), the active layer (152), and the first conductivity semiconductor layer (151) are sequentially etched using a dry etching process to form a plurality of light-emitting layers. Subsequently, the plurality of light-emitting layers are separated from the wafer, and a plurality of semiconductor light-emitting devices are manufactured.

[0187] During the dry etching process, the plasma density varies depending on the location on the wafer and the nanoscale patterns formed for the etching process are different from one another, so the sizes (diameter and / or length) of multiple semiconductor light-emitting elements manufactured on the wafer are different from one another. Therefore, when multiple semiconductor light-emitting elements having different sizes are mounted on a display substrate (301 in FIG. 31), there is a problem that the semiconductor light-emitting elements that do not come into contact with the electrodes on the display substrate (301) do not light up.

[0188] The embodiments may not use a conventional dry etching process. That is, the embodiments do not require a dry etching process.

[0189] Typically, a free object can be freely created according to the shape of the mold. In the embodiment, a semiconductor light-emitting element (150) can be manufactured in a pre-prepared growth hole by utilizing the principle of the mold. That is, the pre-prepared growth hole may have a shape corresponding to the semiconductor light-emitting element (150) of the embodiment. In this case, a first conductivity type semiconductor layer (151), an active layer (152), and a second conductivity type semiconductor layer (153) are sequentially grown in the pre-prepared growth hole using MOCVD equipment, and then a component constituting the growth hole, such as an insulating film (503 in FIG. 16), is removed, thereby allowing the first conductivity type semiconductor layer (151), the active layer (152), and the second conductivity type semiconductor layer (153) grown in the growth hole to be manufactured as is, having a light-emitting part (160).

[0190] Conventionally, a first conductivity type semiconductor layer (151), an active layer (152), and a second conductivity type semiconductor layer (153) were sequentially grown on a wafer, and then a desired semiconductor light-emitting device was manufactured through an etching process. In this case, it was difficult to manufacture semiconductor light-emitting devices of the same shape due to complex factors such as non-uniformity of plasma density, temperature, or power instability during the etching process. In particular, when further miniaturizing the semiconductor light-emitting device, it was very difficult to manufacture a semiconductor light-emitting device of the desired small size and the same shape throughout the entire manufacturing process.

[0191] However, in the embodiment, by performing dry etching on the insulating film (503 in FIG. 15a) formed on the wafer, a growth hole having a minimum diameter and a desired depth in the vertical direction can be formed. Therefore, even if the diameter and length of the semiconductor light-emitting element (150) to be manufactured are minimized, a growth hole acting as a mold is formed to correspond to the diameter and length of the semiconductor light-emitting element (150), thereby obtaining a micro-sized semiconductor light-emitting element (150), and semiconductor light-emitting elements (150) of various shapes can be obtained freely, and each of the multiple semiconductor light-emitting elements (150) manufactured in the multiple growth holes can have the same diameter and / or length.

[0192] As described above, since the embodiment does not use a conventional dry etching process, it can resolve the problems associated with using a conventional dry etching process.

[0193] That is, since a plurality of semiconductor light-emitting elements (150) manufactured on a wafer have the same size, when such a plurality of semiconductor light-emitting elements (150) are mounted on a display substrate (301 of FIG. 31), lighting can be done at all pixels, thereby preventing lighting failures.

[0194] In addition, since the plurality of semiconductor light-emitting elements (150) have the same size, each of the plurality of semiconductor light-emitting elements (150) can have the same brightness. Therefore, when the plurality of semiconductor light-emitting elements (150) are mounted on the display substrate (301), uniform brightness is obtained in all pixels, and the image quality can be improved.

[0195] The specific process of the semiconductor light-emitting element (150) of the embodiment will be explained later.

[0196] Referring again to FIG. 12, the active layer (152) is disposed on the first conductive semiconductor layer (151), and the second conductive semiconductor layer can be disposed on the active layer (152).

[0197] The first conductivity semiconductor layer (151), the active layer (152), and the second conductivity semiconductor layer (153) may be made of a compound semiconductor material. For example, the compound semiconductor material may be a group 3-5 compound semiconductor material, a group 2-6 compound material, etc. For example, the compound semiconductor material may include GaN, InGaN, AlN, AlInN, AlGaN, AlInGaN, InP, GaAs, GaP, GaInP, etc.

[0198] For example, the first conductivity type semiconductor layer (151) may include a first conductivity type dopant, and the second conductivity type semiconductor layer (153) may include a second conductivity type dopant. For example, the first conductivity type dopant may be an n-type dopant such as silicon (Si), and the second conductivity type dopant may be a p-type dopant such as boron (B).

[0199] The active layer (152) is a region that generates light and can generate light having a specific wavelength band according to the material properties of the compound semiconductor. That is, the wavelength band can be determined by the energy bandgap of the compound semiconductor included in the active layer (152). Accordingly, various colors of light can be generated depending on the energy bandgap of the compound semiconductor included in the active layer (152).

[0200] Since light is generated in the active layer (152), if the diameter (or size) of the active layer (152) of each of the plurality of semiconductor light-emitting elements (150) manufactured on the wafer is different, the amount of light from the active layer (152) of each of the plurality of semiconductor light-emitting elements (150) is different. That is, the amount of light from the semiconductor light-emitting element (150) with a larger diameter of the active layer (152) is greater than the amount of light from the semiconductor light-emitting element (150) with a smaller diameter of the active layer (152). The amount of light can be directly related to brightness. That is, the more light there is, the greater the brightness can be.

[0201] In this way, when a display device is manufactured using a plurality of semiconductor light-emitting elements (150) having different diameters manufactured on a wafer, the brightness of each pixel in the display device may differ from each other, which may cause image quality defects.

[0202] According to the embodiment, since the diameter (or size) of each of the plurality of semiconductor light-emitting elements (150) manufactured on a wafer is the same, the brightness in each pixel of the display device using these plurality of semiconductor light-emitting elements (150) is uniform, thereby improving the image quality.

[0203] In addition, according to the embodiment, the depths of the plurality of growth holes provided on the wafer are made equal, so that the lengths of the plurality of semiconductor light-emitting elements (150) manufactured in the plurality of growth holes are equal. Since both ends of the plurality of semiconductor light-emitting elements (150) with equal lengths are stably in contact with the wiring electrodes, a failure to light up the semiconductor light-emitting elements (150) can be prevented.

[0204] In addition, according to the embodiment, the inner surface of a plurality of growth holes provided on a wafer has a surface perpendicular to the bottom surface, and the surface perpendicular has a smooth surface with minimized roughness, so the side of the semiconductor light-emitting element (150) manufactured in the growth hole has a surface perpendicular to the bottom surface and the roughness of the surface perpendicular can be minimized.

[0205] In addition, according to the embodiment, by forming various shapes of a plurality of growth holes provided on a wafer, the shape of the semiconductor light-emitting element (150) manufactured in the growth holes can be formed freely.

[0206] In the following embodiments, the growth hole is described as being limited to being circular when viewed from above, but the growth hole of the embodiment may have a square, polygonal, star shape, etc. In addition, by forming the inner surface of the growth hole as a surface other than a vertical surface, such as a curved surface, a rounded surface, or a concave surface, the side of the semiconductor light-emitting element (150) manufactured in this growth hole may also have various shapes.

[0207] FIGS. 13 to 17 illustrate a manufacturing process of a semiconductor light-emitting device according to a first embodiment.

[0208] In the following description, reference to FIG. 12 may be used for the reference numerals for components not shown in FIG. 13 to FIG. 17.

[0209] As illustrated in FIG. 13, a wafer (501) may be provided. The wafer (501) may be made of, for example, sapphire material, but is not limited thereto.

[0210] A seed layer (502) may be formed on a wafer (501). The seed layer (502) may include a group II-IV compound or a group III-V compound, but is not limited thereto. The seed layer (502) may serve as a seed for growing a plurality of semiconductor layers constituting a semiconductor light-emitting device.

[0211] If the wafer (501) contains a group II-IV compound or a group III-V compound and can serve as a seed, the seed layer (502) may be omitted.

[0212] As illustrated in FIG. 14, an insulating film (503) and a mask film (504) may be sequentially formed on a seed layer (502). For example, the insulating film (503) may be made of an inorganic material such as SiOx, SiNx, etc. The mask film (504) may be made of a metal such as chromium (Cr). Subsequently, a photosensitive film may be patterned to form a photosensitive pattern (505).

[0213] The insulating film (503) can be formed, for example, using thermal deposition equipment. When the insulating film (503) is formed using thermal deposition equipment, the film quality of the insulating film (503) is hard and the film quality characteristics are excellent, so that later, the semiconductor light-emitting device can be formed with excellent film quality, and the electrical and optical characteristics can be improved.

[0214] As shown in FIGS. 15a and 15b, a mask pattern (504a) can be formed by patterning a mask film (504) using a photosensitive pattern (505) as a mask.

[0215] The photosensitive pattern (505) and mask pattern (504a) may have a transparent area corresponding to the growth hole (510) and a non-transparent area which is the remaining area.

[0216] Afterward, after the photosensitive pattern (505) is removed, the insulating film (503) can be patterned using the mask pattern (504a) as a mask to form a plurality of growth holes (510) on the wafer (501). An etching gas for forming the growth holes (510) is applied to the insulating film (503) through the transmission area of ​​the mask pattern (504a), and the insulating film (503) corresponding to the transmission area of ​​the mask pattern (504a) is removed so that the growth holes (510) can be formed. Accordingly, the mask pattern (504a) can be formed by considering the shape of the growth holes (510) or the diameter of the growth holes (510).

[0217] The bottom portion of the growth hole (510) may be the upper surface of the seed layer (502). That is, the upper surface of the seed layer (502) may be exposed by the growth hole (510).

[0218] Multiple growth holes (510) may be formed considering the number of semiconductor light-emitting devices to be manufactured per wafer (501). Additionally, the multiple growth holes (510) may be spaced apart from each other at an appropriate distance. For example, the spacing between the multiple growth holes (510) may be equal to or greater than the diameter of the growth holes (510), but is not limited thereto.

[0219] The growth hole (510) can be formed using photolithography or laser interference lithography.

[0220] When using photolithography, unidirectional etching is possible, so a growth hole (510) can be formed with a constant shape and a deep depth with the same diameter. That is, by using photolithography to etch mainly in the depth direction, a growth hole (510) can be formed with a deep depth. For example, the inner surface of the growth hole (510) may have a straight surface perpendicular to the bottom portion, but is not limited thereto.

[0221] When using laser interference lithography, a growth hole (510) having a smaller diameter than when using photolithography can be formed.

[0222] For example, the diameter of the hole may be 1 μm or less. For example, the diameter of the hole may be 500 nm to 1 μm.

[0223] As illustrated in FIG. 16, a light-emitting part (160) can be grown within a growth hole (510) using a seed layer (502) exposed within the growth hole (510) as a seed. As illustrated in FIG. 12, the light-emitting part (160) may include a first conductivity semiconductor layer (151), an active layer (152), and a second conductivity semiconductor layer (153). For example, using MOCVD equipment, a first conductivity semiconductor layer (151) can be grown on the seed layer (502) using the seed layer (502) as a seed within the growth hole (510), an active layer (152) can be grown on the first conductivity semiconductor layer (151), and a second conductivity semiconductor layer (153) can be grown on the active layer (152). At this time, the seed layer (502) is placed only within the growth hole (510), and since the seed layer (502) is not placed on the upper surface of the insulating film (503), the light-emitting part (160) is grown only within the growth hole (510) and is not grown on the upper surface of the insulating film (503).

[0224] As shown in FIG. 16, the upper surface of the light-emitting part (160) may be grown within the growth hole (510) so as to be aligned with the upper surface of the insulating film (503), or it may be grown lower or higher than the upper surface of the insulating film (503). For example, if the upper surface of the light-emitting part (160) is grown lower than the upper surface of the insulating film (503), the upper surface of the light-emitting part (160) may have a downwardly concave shape. For example, if the upper surface of the light-emitting part (160) is grown higher than the upper surface of the insulating film (503), the upper surface of the light-emitting part (160) may have an upwardly convex shape. Here, the downward direction may be the direction toward the wafer (501), and the upward direction may be the direction toward the wafer (501).

[0225] As illustrated in FIG. 17, a plurality of light-emitting parts (160) can be positioned on the wafer (501) by removing the insulating film (503). For example, the insulating film (503) can be removed using a wet etching process, but is not limited thereto.

[0226] Although not shown, a separate insulating film (503) may be formed along the perimeter of the light-emitting part (160). Afterward, the insulating film (503) formed on the upper side of the light-emitting part (160) is removed, and an upper electrode may be formed on the upper side of the light-emitting part (160). Afterward, the upper side of a plurality of light-emitting parts (160) is attached to a separate substrate, and then the wafer (501) may be separated. Afterward, a lower electrode may be formed on the lower side of the light-emitting part (160) from which the wafer (501) has been separated.

[0227] As another example, after first separating a plurality of light-emitting parts (160) from the wafer (501), an insulating film (503), an upper electrode, and a lower electrode may be formed.

[0228] As illustrated in FIG. 17, a plurality of light-emitting parts (160) manufactured by growing in a plurality of growth holes (510) having the same diameter and the same depth may also have the same diameter and the same depth. At this time, the light-emitting part (160) is a semiconductor light-emitting device, and the side of the light-emitting part (160) may have a straight plane perpendicular to the lower surface of the light-emitting part (160), but is not limited thereto.

[0229] The light-emitting part (160) may have a shape corresponding to the shape of the growth hole (510). The light-emitting part (160) may have a circular, square, polygonal, star shape, etc.

[0230] According to the embodiment, a plurality of light-emitting parts (160) having the same diameter and the same depth can be easily manufactured in large quantities. When implementing a display using the plurality of light-emitting parts (160) manufactured in this way, i.e., semiconductor light-emitting elements, uniform brightness can be secured and lighting defects can be minimized.

[0231] According to the embodiment, semiconductor light-emitting devices of various shapes can be freely manufactured by changing the shape of the growth hole (510).

[0232] Hereinafter, a second embodiment will be described with reference to FIG. 18.

[0233] FIG. 18 is a cross-sectional view illustrating a semiconductor light-emitting element according to a second embodiment. FIG. 19 is a cross-sectional view illustrating the light-emitting part of FIG. 18 in detail.

[0234] The second embodiment is identical to the first embodiment except for the insulating layer (155) and electrodes (156 to 158). In the second embodiment, the same reference numerals are used for identical components having the same shape, structure, and / or function as in the first embodiment, and detailed descriptions are omitted.

[0235] Referring to FIG. 18, a semiconductor light-emitting element (150A) according to the second embodiment may include a light-emitting part (160), an insulating layer (155), and electrodes (156 to 158).

[0236] The light-emitting part (160) may have a first region (161) and a second region (162). The first region (161) and the second region (162) may be located along the long axis direction of the light-emitting part (160). The long axis direction may be the length direction of the light-emitting part (160). The second region (162) may be placed on the first region (161). Or the first region (161) may be placed below the second region (162).

[0237] As will be explained later, both the first region (161) and the second region (162) of the light-emitting part (160) are manufactured in growth holes formed on the wafer (501), so no etching process is involved. Since the light-emitting part (160) is manufactured corresponding to the inner surface of the growth hole, the diameter of the first region (161) and the diameter of the second region (162) may be the same. In addition, the side of the first region (161) and the side of the second region (162) may coincide along the long axis direction or the length direction of the light-emitting part (160).

[0238] Accordingly, a semiconductor light-emitting element (150A) having an insulating layer (155) and electrodes (156 to 158) disposed on a light-emitting part (160) manufactured in a plurality of growth holes on a wafer (501) may have the same diameter on both the lower and upper sides and the same length. When implementing a display using a plurality of semiconductor light-emitting elements (150A), both ends of each of the plurality of semiconductor light-emitting elements (150A) are electrically contacted with assembly wiring to prevent lighting failure, and the brightness between each pixel is uniform so that the image quality can be improved.

[0239] As illustrated in FIG. 19, the light-emitting portion (160) may include a first conductivity semiconductor layer (151), an active layer (152), and a second conductivity semiconductor layer (153). In this case, the first region (161) may include the first conductivity semiconductor layer (151) and the active layer (152), and the second region (162) may include the second conductivity semiconductor layer (153). For example, the first region (161) may include not only the first conductivity semiconductor layer (151) and the active layer (152) but also a part of the second conductivity semiconductor layer (153) (second-1 conductivity semiconductor layer (153_1)). For example, the second region (162) may include another part of the second conductivity semiconductor layer (153) (second-2 conductivity semiconductor layer (153-2)). The second-1 conductive semiconductor layer (153_1) and the second-2 conductive semiconductor layer (153-2) are distinguished for convenience and can be formed integrally by the same process using substantially the same material.

[0240] The insulating layer (155) may surround the side of the first region (161). The insulating layer (155) may be a protective layer that protects the light-emitting part (160).

[0241] For example, the insulating layer (155) may be arranged along the lateral perimeter of the first region (161). For example, the insulating layer (155) may surround the sides of each of the first conductive semiconductor layer (151), the active layer (152), and the second-1 conductive semiconductor layer (153_1).

[0242] For example, the insulating layer (155) can be made of an inorganic material such as SiOx, SiNx, etc.

[0243] For example, the insulating layer (155) can prevent leakage current flowing along the side of the light-emitting part (160) during light emission. For example, the insulating layer (155) can prevent an electrical short circuit between the first conductive semiconductor layer (151) and the second conductive semiconductor layer (153) caused by foreign substances. For example, when semiconductor light-emitting elements (150A) are assembled on a display substrate (301 in FIG. 31) by a self-assembly method, the insulating layer (155) ensures that the semiconductor light-emitting elements (150A) are properly assembled by causing the lower side of the semiconductor light-emitting elements (150A), that is, the first conductive semiconductor layer (151), to come into contact with the display substrate (301).

[0244] The electrode may include a first electrode (156), a second electrode (157), and a third electrode (158). The first electrode (156) and the second electrode (157) may constitute an upper electrode, and the third electrode (158) may be a lower electrode.

[0245] The electrodes (156 to 158) may be made of a metal with excellent conductivity. The electrodes (156 to 158) may include at least one of copper (Cu), aluminum (Al), titanium (Ti), nickel (Ni), platinum (Pt), gold (Au), and silver (Ag).

[0246] The first electrode (156) can surround the side of the second region (162).

[0247] As will be explained later, an insulating layer (155) can be formed using the first electrode (156) as a mask. Accordingly, the thickness (t2) of the insulating layer (155) can be the same as the thickness (t1) of the first electrode (156). Since the insulating layer (155) is formed using the first electrode (156) as a mask, there is no need to form a separate mask to form the insulating layer (155), so the process is simple and material costs can be reduced.

[0248] Meanwhile, the first electrode (156) may not be in contact with the active layer (152). When the first electrode (156) is in contact with the active layer (152), current does not flow to the active layer (152) through the second conductivity type semiconductor layer (153) but flows directly to the active layer (152) through the first electrode (156), so holes are not generated in the second conductivity type semiconductor layer (153) and the semiconductor light-emitting element (150A) does not emit light.

[0249] Accordingly, the first electrode (156) is positioned around the upper circumference of the second conductive semiconductor layer (153) and is spaced apart from the active layer (152), so it may not come into contact with the active layer (152).

[0250] For example, the first electrode (156) can overlap with the insulating layer (155) along the long axis direction. For example, the first electrode (156) and the insulating layer (155) can come into contact along the perimeter of the light-emitting part (160). As will be explained later, since the insulating layer (155) is formed using the first electrode (156) as a mask, the insulating layer (155) can be formed in the exact shape of the first electrode (156). Accordingly, the thickness (t2) of the insulating layer (155) is the same as the thickness (t1) of the first electrode (156), the upper surface of the insulating layer (155) comes into contact with the lower surface of the first electrode (156), and the first electrode (156) and the insulating layer (155) can overlap along the long axis direction.

[0251] Meanwhile, the second electrode (157) may be placed on the upper surface of the second region (162) of the light-emitting part (160). The second electrode (157) may be omitted.

[0252] The first electrode (156) and the second electrode (157) may be formed integrally, but are not limited thereto. For example, the second electrode (157) may be formed by extending from the first electrode (156). That is, the first electrode (156) may surround the side of the second region (162) of the light-emitting part (160), and the second electrode (157) may be extended from the first electrode (156) and placed on the upper surface of the second region (162).

[0253] The thickness (t1) of the first electrode (156) and the thickness (t3) of the second electrode (157) may be different. For example, the thickness (t1) of the first electrode (156) may be greater than the thickness (t3) of the second electrode (157). As will be explained later, when an etching process is performed without a mask after a metal film (511 in FIG. 25) is formed on the side and top surfaces of the light-emitting part (160), the metal film (511) on the top surface of the light-emitting part (160) is removed faster than the metal film (511) on the side surface of the light-emitting part (160). Therefore, the thickness (t1) of the metal film (511) on the side surface of the light-emitting part (160), i.e., the first electrode (156), may be greater than the thickness (t3) of the metal film (511) on the top surface of the light-emitting part (160), i.e., the second electrode (157). The metal film (511) on the upper surface of the light-emitting part (160), i.e., the second electrode (157), may be removed, and only the metal film (511) on the side surface of the light-emitting part (160), i.e., the first electrode (156), may remain.

[0254] Meanwhile, the third electrode (158) may be disposed on the lower surface of the first region (161) of the light-emitting part (160). For example, the third electrode (158) may include at least one layer.

[0255] The third electrode (158) can be placed on the lower surface of the insulating layer (155). That is, the insulating layer (155) and the third electrode (158) can be in contact along the perimeter of the light-emitting part (160). For example, the insulating layer (155) and the third electrode (158) can be overlapped along the long axis direction.

[0256] Although not shown in the drawing, the third electrode (158) may not be placed on the lower surface of the insulating layer (155) but only on the lower surface of the first region (161) of the light-emitting part (160).

[0257] FIGS. 20 to 28 illustrate a manufacturing process of a semiconductor light-emitting device according to a second embodiment.

[0258] In the following description, reference numerals for components not shown in FIGS. 20 to 28 may be referenced to FIGS. 18 and FIGS. 19.

[0259] FIGS. 20 to 23 are identical to FIGS. 13 to 16, so a detailed description is omitted.

[0260] As illustrated in FIG. 24, a portion of the insulating film (503) can be removed using an etching process. By removing a portion of the insulating film (503), a portion of the light-emitting part (160), such as a portion of the second conductive semiconductor layer (153), i.e., the second-second conductive semiconductor layer (153-2), can be exposed. The depth (d1) of the removed insulating film (503) may be equal to the thickness of the second-second conductive semiconductor layer (153-2).

[0261] For example, the active layer (152) of the light-emitting part (160) may be embedded in the insulating film (503) so as not to be exposed. In addition, another part of the second conductive semiconductor layer (153), namely the second-1 conductive semiconductor layer (153_1), may also be embedded in the insulating film (503) so as not to be exposed.

[0262] As illustrated in FIG. 25, a metal film (511) may be formed on the insulating film (503) and the light-emitting part (160). For example, the metal film (511) may be formed using a deposition process by sputtering, but is not limited thereto.

[0263] The thickness of the metal film (511) formed on the insulating film (503) and the light-emitting part (160) may vary, but is not limited thereto. For example, the thickness of the metal film (511) on the insulating film (503) may be the smallest, and the metal film (511) formed on the side and top surfaces of the second-second conductive semiconductor layer (153-2) of the light-emitting part (160) may be formed relatively thick.

[0264] As illustrated in FIG. 26, a dry etching process can be performed on the metal film (511). Since the etching rate in the dry etching process is greater in the vertical direction than in the horizontal direction, even if the metal film (511) on the thinnest insulating film (503) is completely removed, only a portion of the metal film (511) formed on the side and top surfaces of the second-second conductive semiconductor layer (153-2) can be removed. In particular, the metal film (511) on the top surface of the second-second conductive semiconductor layer (153-2) can be removed more quickly than the metal film (511) on the side surface of the second-second conductive semiconductor layer (153-2).

[0265] Accordingly, the metal film (511) on the insulating film (503) is completely removed, and the thickness of the metal film (511) on the side surface of the second-second conductive semiconductor layer (153-2) may be greater than the thickness of the metal film (511) on the upper surface of the second-second conductive semiconductor layer (153-2). The metal film (511) on the side surface of the second-second conductive semiconductor layer (153-2) may be the first electrode (156), and the metal film (511) on the upper surface of the second-second conductive semiconductor layer (153-2) may be the second electrode (157).

[0266] As illustrated in FIG. 27, an insulating film (503) can be removed by performing a dry etching process using an upper electrode (156, 157) including a first electrode (156) and a second electrode (157) as a mask. Since the etching proceeds along the vertical direction by the dry etching process, the insulating film (503) exposed between the upper electrodes (156, 157) can be removed vertically. At this time, the insulating film (503) that overlaps vertically with the upper electrodes (156, 157), particularly the first electrode (156), may remain without being removed by the dry etching process and form an insulating layer (155).

[0267] Since the insulating layer (155) is formed by a dry etching process, the outer surface of the insulating layer (155) may have irregularities. Accordingly, the light extraction efficiency of the light-emitting part (160) is increased by the irregularities provided on the outer surface of the insulating layer (155), thereby improving light efficiency or light output, which can lead to an increase in brightness when implementing a display.

[0268] The dry etching process can be continuously performed until the upper surface of the seed layer (502) is exposed.

[0269] Accordingly, an insulating layer (155) is disposed around the perimeter of the light-emitting part (160), and an upper electrode including first and second electrodes (156, 157) may be disposed on the upper side of the light-emitting part (160).

[0270] As illustrated in FIG. 28, a substrate (520) can be positioned on a wafer (501) and attached to upper electrodes (156, 157). That is, the substrate (520) can be attached to upper electrodes (156, 157) using an adhesive member (521), such as tape. The substrate (520) may be glass, but is not limited thereto.

[0271] Afterwards, a plurality of light-emitting parts (160) on a wafer (501) can be transferred onto a substrate (520) using a laser lift-off process. That is, by focusing a laser on a seed layer (502), a plurality of light-emitting parts (160) can be separated from the wafer (501) based on the seed layer (502).

[0272] In another embodiment, a plurality of light-emitting parts (160) on a wafer (501) can be transferred onto a substrate (520) using a chemical lift-off process. For example, after immersing the wafer (501) in a tank containing an etching solution, ultrasonic waves are applied, and the seed layer (502) is removed by the etching solution, and vibration is applied to the wafer (501) by the ultrasonic waves, so that a plurality of light-emitting parts (160) can be separated from the wafer (501) based on the seed layer (502).

[0273] When using a chemical lift-off process, the lower surface of the light-emitting part (160) can have a smooth flat surface.

[0274] Although not shown, a lower electrode (158) may be formed on the lower surface of the light-emitting part (160) in a subsequent process so that a semiconductor light-emitting element can be manufactured. Subsequently, the semiconductor light-emitting elements can be separated from the substrate (520).

[0275] According to an embodiment, a plurality of semiconductor layers can be grown in growth holes (510) pre-formed on a wafer (501) to obtain a plurality of light-emitting parts (160) with the same diameter and / or length.

[0276] According to the embodiment, in the process of manufacturing a plurality of light-emitting parts (160), electrodes (156 to 158) and an insulating layer (155) are formed, so there is no need to form a separate electrode or an insulating layer (155), which simplifies the process and reduces material costs.

[0277] According to the embodiment, since the insulating layer (155) is formed using the upper electrode (156, 157), particularly the first electrode (156), as a mask, there is no need to form a separate mask, so the process is simple and material costs can be reduced.

[0278] As described above, since the diameter and / or length of the plurality of semiconductor light-emitting elements manufactured on the wafer (501) are the same, when implementing a display using these semiconductor elements, lighting defects can be prevented and brightness deviations can be eliminated to improve image quality.

[0279] Hereinafter, a third embodiment will be described with reference to FIG. 29.

[0280] FIG. 29 is a cross-sectional view illustrating a semiconductor light-emitting element according to a third embodiment.

[0281] The third embodiment is identical to the second embodiment except for the shape of the insulating layer (155). In the third embodiment, the same reference numerals are used for identical components having the same shape, structure, and / or function as in the second embodiment, and detailed descriptions are omitted.

[0282] Referring to FIG. 29, a semiconductor light-emitting element (150B) according to the third embodiment may include a light-emitting part (160)(160), an insulating layer (155), and electrodes (156 to 158).

[0283] The light-emitting part (160) has been described in detail in the first and second embodiments, so a detailed description is omitted.

[0284] The insulating layer (155) may include a first insulating layer (155-1) and a second insulating layer (155-2).

[0285] The first insulating layer (155-1) may be positioned along part of the perimeter of the first region (161), and the second insulating layer (155-2) may be positioned along another part of the perimeter of the first region (161). For example, the first insulating layer (155-1) may surround the side of the first conductive semiconductor layer (151), and the second insulating layer (155-2) may surround the side of the active layer (152). The second insulating layer (155-2) may surround the side of the second conductive semiconductor layer (153), i.e., the second-1 conductive semiconductor layer (153_1), as well as the active layer (152).

[0286] For example, the thickness (t21) of the first insulating layer (155-1) may be greater than the thickness (t22) of the second insulating layer (155-2). For example, the outer surface of the first insulating layer (155-1) may have a concave round shape. For example, the thickness (t21) of the first insulating layer (155-1) may be thickest at the lower side of the first region (161). That is, the first insulating layer (155-1) may have the same thickness (t22) as the second insulating layer (155-2) in the first insulating region that contacts the second insulating layer (155-2). The first insulating layer (155-1) extends from the first insulating region, and as the increase in thickness (t21) becomes larger, the outer surface of the first insulating layer (155-1) may have a concave round shape. The concave round shape of the first insulating layer (155-1) can be described in the manufacturing process of the semiconductor light-emitting device (150B). In FIG. 27, when the insulating film (503) is removed by a dry etching process, the etching rate in the vertical direction is greater than the etching rate in the horizontal direction, so the insulating film (503) is mainly removed along the vertical direction, but can also be finely removed in the horizontal direction. Therefore, as the upper side of the insulating film (503) is continuously removed along the horizontal direction while the lower side of the insulating film (503) is etched, when the dry etching process is completed, the first insulating layer (155-1) having a concave round shape can be formed as shown in FIG. 29.

[0287] Meanwhile, the lower electrode (158) can be placed on the lower surface of the light-emitting part (160) and the lower surface of the insulating layer (155). Since the lower electrode (158) has the thickest thickness (t21) on the lower side of the insulating layer (155), i.e., the first insulating layer (155-1), the lower electrode (158) can have a larger diameter than the upper electrodes (156, 157).

[0288] Since the lower electrode (158) has a relatively large diameter, the contact area between the power distribution electrode and the lower electrode (158) is large during the wiring electrode pattern process after mounting on the display substrate (301 in FIG. 31), so contact failure can be prevented.

[0289] [Display device]

[0290] FIG. 30 is a plan view illustrating a display device according to an embodiment. FIG. 31 is a cross-sectional view illustrating a display device according to an embodiment.

[0291] In the following description, reference numerals for components not shown in FIGS. 30 and FIGS. 31 may be referenced in FIGS. 12 to FIGS. 29.

[0292] Referring to FIGS. 30 and 31, a display device (300) according to an embodiment may include a substrate (301), a dielectric layer (302), assembly wiring (310, 320), and wiring electrodes (330, 340). At least one layer may be disposed on the wiring electrodes (330, 340).

[0293] Since the substrate (301) is the same as the substrate (200) of FIG. 9 and the assembly wiring (310, 320) is the same as the wiring electrodes (201, 202) of FIG. 9, a detailed description is omitted.

[0294] A plurality of semiconductor light-emitting elements (150A) can be aligned between the assembly wiring (310, 320) by the dielectrophoretic force caused by the electric field generated between the assembly wiring (310, 320).

[0295] FIGS. 30 and 31 illustrate a semiconductor light-emitting element (150A) according to a second embodiment, but a display device (300) may also be manufactured using semiconductor light-emitting elements (150, 150B) according to a first and third embodiment.

[0296] The dielectric layer (302) is placed on the assembled wiring (310, 320) to help generate an electric field and prevent short circuits between the assembled wiring (310, 320).

[0297] The wiring electrodes (330, 340) are placed on the assembly wiring (310, 320) and can be electrically connected to each of the plurality of semiconductor light-emitting elements (150A).

[0298] As an example, when a plurality of semiconductor light-emitting elements (150A) generate monochromatic light, such as blue light, the first wiring electrode (330) may be commonly connected to one side of the plurality of semiconductor light-emitting elements (150A), and the second wiring electrode (340) may be commonly connected to the other side of the plurality of semiconductor light-emitting elements. A portion of the first wiring electrode (330) may be placed on one side of each of the plurality of semiconductor light-emitting elements (150A), such as the upper electrode (156, 157), and a portion of the second wiring electrode (340) may be placed on the other side of each of the plurality of semiconductor light-emitting elements (150A), such as the lower electrode (158). For example, the first wiring electrode (330) may be an anode electrode and the second wiring electrode (340) may be a cathode electrode, but is not limited thereto.

[0299] The first and second wiring electrodes (330, 340) share a common power source for emitting light from a plurality of semiconductor light-emitting elements (150A), while also being able to firmly fix the plurality of semiconductor light-emitting elements (150A) to the dielectric layer (302).

[0300] As another example, a plurality of semiconductor light-emitting elements (150A) may include a first semiconductor light-emitting element that generates red light, a second semiconductor light-emitting element that generates green light, and a third semiconductor light-emitting element that generates blue light.

[0301] In this case, the first wiring electrode (330) may include a first-1 wiring electrode, a first-2 wiring electrode, and a first-3 wiring electrode. The first-1 wiring electrode may be electrically connected to the upper electrode (156, 157) of the first semiconductor light-emitting element, the first-2 wiring electrode may be electrically connected to the upper electrode (156, 157) of the second semiconductor light-emitting element, and the first-3 wiring electrode may be electrically connected to the upper electrode (156, 157) of the third semiconductor light-emitting element. For example, the second wiring electrode (340) may be commonly connected to the lower electrode (158) of each of the first to third semiconductor light-emitting elements.

[0302] The foregoing detailed description should not be interpreted restrictively in all respects and should be considered exemplary. The scope of the embodiments should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the embodiments are included within the scope of the embodiments. Industrial applicability

[0303] The embodiment can be adopted in the field of displays that display images or information.

[0304] The embodiment can be adopted in the field of displays that display images or information using semiconductor light-emitting elements.

[0305] The embodiment can be adopted in the field of displaying images or information using micro-scale or nano-scale semiconductor light-emitting devices.

Claims

Claim 1 A semiconductor light-emitting device comprising: a light-emitting part having a first region and a second region along the long axis direction; an insulating layer surrounding the side of the first region; and a first electrode surrounding the side of the second region, wherein the thickness of the insulating layer is the same as the thickness of the first electrode, and the light-emitting part comprises a first conductive semiconductor layer; an active layer on the first conductive semiconductor layer; and a second conductive semiconductor layer on the active layer, wherein the insulating layer comprises a first insulating layer surrounding the side of the first conductive semiconductor layer; and a second insulating layer surrounding the side of the active layer, and the outer surface of the first insulating layer has a concave round shape. Claim 2 A semiconductor light-emitting device according to claim 1, wherein the first region comprises the first conductivity type semiconductor layer and the active layer, and the second region comprises the second conductivity type semiconductor layer. Claim 3 In claim 1, the side of the first region and the side of the second region are a semiconductor light-emitting element that aligns along the long axis direction. Claim 4 A semiconductor light-emitting device according to claim 1, wherein the thickness of the first insulating layer is greater than the thickness of the second insulating layer. Claim 5 delete Claim 6 In claim 1, the thickness of the first insulating layer is the thickest semiconductor light-emitting element at the lower side of the first region. Claim 7 A semiconductor light-emitting device according to claim 1, wherein the first electrode and the insulating layer overlap each other along the long axis direction. Claim 8 A semiconductor light-emitting device according to claim 1, comprising a second electrode disposed on the upper surface of the second region. Claim 9 A semiconductor light-emitting device according to claim 1, comprising a third electrode on the lower surface of the first region. Claim 10 A display device comprising: a substrate; first and second assembly wirings on the substrate; a plurality of semiconductor light-emitting elements disposed on the first and second assembly wirings and generating different colored light; a first wiring electrode on one side of each of the plurality of semiconductor light-emitting elements; and a second wiring electrode on the other side of each of the plurality of semiconductor light-emitting elements, wherein each of the plurality of semiconductor light-emitting elements comprises: a light-emitting part having a first region and a second region along the long axis direction; an insulating layer surrounding the side of the first region; and a first electrode surrounding the side of the second region, wherein the thickness of the insulating layer is the same as the thickness of the first electrode, and the light-emitting part comprises: a first conductive semiconductor layer; an active layer on the first conductive semiconductor layer; and a second conductive semiconductor layer on the active layer, wherein the insulating layer comprises: a first insulating layer surrounding the side of the first conductive semiconductor layer; and a second insulating layer surrounding the side of the active layer, and the outer surface of the first insulating layer has a concave round shape. Claim 11 delete Claim 12 delete Claim 13 delete Claim 14 delete Claim 15 delete Claim 16 delete Claim 17 delete Claim 18 delete Claim 19 delete Claim 20 delete

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