Apparatus and method for manufacturing display panel

Abstract

To provide an apparatus for manufacturing a display panel and a method for manufacturing the display panel, capable of enhancing uniformity of a pressurizing force generated by pressurizing a laser translucent member.SOLUTION: (1) a seating stage on which a display substrate is seated, (2) a mask member which is disposed on a front side of the seating stage and in which a first opening corresponding to a transmission region of a laser beam is partitioned and formed, (3) a pressing unit including a pressing member which presses a plurality of donor substrates disposed on the display substrate, A support member having a plurality of second openings formed in a region corresponding to the donor substrate arranged on the display substrate, (5) a pressing unit including a pressing member configured to press the support member, and (6) a laser irradiation unit disposed above the mask member and configured to irradiate a light emitting device of the donor substrate with laser light, wherein the support member has a height equal to a sum of a thickness of the donor substrate and a height of the light emitting device.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a display panel manufacturing apparatus and manufacturing method. [Background technology]

[0002] Micro LEDs are ultra-small inorganic light-emitting materials that emit light by themselves without the need for a backlight. Specifically, micro LEDs are about one-tenth the length and one-hundredth the area of ​​organic light-emitting diode chips. As an example, micro LEDs refer to ultra-small LEDs with width, length, and height ranging from approximately 10 μm to 100 μm.

[0003] Micro LEDs can be manufactured by growing multiple chips on a growth substrate such as a wafer using an epitaxial process, etc. The micro LEDs manufactured in this way are usually transferred to an interposer substrate and then transferred to a target substrate for use as a display module.

[0004] The micro LED transfer process can use a laser transfer method in which a laser beam is irradiated onto the back of the relay substrate (multiple micro LEDs are arranged on the front of the relay substrate) to transfer the micro LEDs on the relay substrate to the target substrate.

[0005] Conventional laser transfer methods use a pressure member that allows the laser to pass through and applies pressure to the donor substrate while the laser is passing through. In this case, there is a problem that the pressure member warps due to the temperature and pressure of the laser. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent Publication No. 2020-0114077 (KR2020-0114077A) Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a display panel manufacturing apparatus that increases the uniformity of the pressure generated by pressing a laser transmissive member.

[0008] The problems to be solved by the present invention are not limited to those described above, and further technical problems not mentioned here will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0009] In one embodiment for solving the above problem, a display panel manufacturing apparatus includes: (1) a mounting stage on which a display substrate is mounted; (2) a mask member disposed on the front side of the mounting stage and defining first openings corresponding to the transmission areas of the laser beam; (3) a pressure unit including a pressure member that presses a plurality of donor substrates disposed on the display substrate; (4) a support member disposed on the display substrate and having a plurality of second openings formed in areas corresponding to the donor substrates arranged on the display substrate; (5) a pressure unit including a pressure member that presses the support member; and (6) a laser irradiation unit disposed above the mask member that irradiates laser light onto light-emitting elements of the donor substrate, wherein the support member has a height equal to the sum of the thickness of the donor substrate and the height of the light-emitting elements.

[0010] The second opening can overlap the first opening and the donor substrate.

[0011] The support member may protrude outward beyond the display substrate.

[0012] The mask member may include a base layer that transmits laser light, and a light-shielding pattern layer that is disposed on the base layer and includes the opening.

[0013] The pressurizing member is disposed on the support member and includes a first light-transmitting plate and a second light-transmitting plate overlapping each other in a thickness direction, forming a sealed space between the first light-transmitting plate and the second light-transmitting plate. The pressurizing member may further include a gas pressure regulator that adjusts the gas pressure in the sealed space, and a gas conduit connected between the gas pressure regulator and the sealed space.

[0014] The second light-transmitting plate can move downward when the gas pressure in the sealed space increases.

[0015] The display panel manufacturing apparatus may further include a holding frame that fixes both ends of the first light-transmitting plate and the second light-transmitting plate, and a buffer material disposed between the second light-transmitting plate and the holding frame.

[0016] The mask member is a photomask, and the photomask may include: (1) a transparent or translucent flat plate-shaped base layer; (2) a light-shielding pattern layer disposed on the base layer, having a light-shielding property and a light-shielding pattern in which the first opening is defined; and (3) a protective layer disposed on the light-shielding pattern layer.

[0017] The base layer may be disposed closer to the display substrate than the protective layer.

[0018] The base layer may be disposed closer to the laser irradiation portion than the protective layer.

[0019] The display panel manufacturing apparatus may further include a first mounting member attached to one surface of the outer periphery of the mask member and supporting the mask, and a second mounting member attached to one surface of the outer periphery of the support member and supporting the mask.

[0020] The mask member may be disposed between the support member and the pressure member.

[0021] The mask member may be disposed between the pressure member and the laser irradiation unit.

[0022] The mask member may be a metal mask having reflectivity and defining the first opening.

[0023] The first opening includes a first side and a second side opposite to the first side, and may be an isosceles trapezoid in which a first angle formed between the first side and one surface of the reflective mask and an angle formed between the one surface of the reflective mask and the second side are the same, or the first side and the second side may have curvature.

[0024] The first light-transmitting plate and the second light-transmitting plate may be formed of a rigid material.

[0025] The first light-transmitting plate may be made of a rigid material, and the second light-transmitting plate may be made of an elastic material.

[0026] A method for manufacturing a display panel according to one embodiment includes the steps of: placing a display substrate on a mounting stage; placing a plurality of donor substrates and a support member on the display substrate, and placing one donor substrate in each of a plurality of second openings defined in the support member; placing a mask member and a pressure member on the donor substrate; and pressing the donor substrate with the pressure member and irradiating laser light onto the light-emitting elements of the donor substrate through the first openings defined in the mask member, wherein the support member may have a height equal to the sum of the thickness of the donor substrate and the height of the light-emitting elements.

[0027] The pressure member is disposed on the support member and includes a first light-transmitting plate and a second light-transmitting plate overlapping each other in a thickness direction, forming an airtight space between the first light-transmitting plate and the second light-transmitting plate. The pressure member can adjust the gas pressure in the airtight space to move the second light-transmitting plate downward and pressurize the donor substrate.

[0028] In the step of irradiating laser light onto the light-emitting element of the donor substrate, the laser irradiation unit is positioned above the mask member, and when laser light is irradiated onto the mask member, the laser light that passes through the first opening of the mask member passes through the second opening of the support member and is irradiated onto the light-emitting element of the donor substrate, and the laser light irradiated onto areas other than the first opening of the mask member can be blocked. [Effects of the Invention]

[0029] According to the display panel manufacturing apparatus of the embodiment, the laser beam irradiated to the peripheral area other than the micro LEDs can be reflected by the reflective member of the light-transmitting plate to protect the display substrate from the laser beam. Also, the support member can be used to apply a uniform pressure to the multiple donor substrates. This prevents manufacturing defects in the target substrates and display panels and improves manufacturing efficiency.

[0030] The effects of the embodiments are not limited to the above examples, and a wider variety of effects are included in this specification. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is a plan view of a display device according to an embodiment. [Figure 2] FIG. 2 is a plan view schematically illustrating a light-emitting region of each pixel according to an embodiment. [Figure 3] FIG. 10 is a plan view schematically illustrating a light-emitting region of each pixel according to another embodiment. [Figure 4] 3 is a cross-sectional view according to one embodiment, schematically illustrating a cross section taken along line AA' in FIG. 2. FIG. [Figure 5] FIG. 5 is an enlarged view schematically illustrating the first light-emitting region of FIG. 4. [Figure 6] FIG. 6 is a cross-sectional view specifically showing the light-emitting element of FIG. 5. [Figure 7] 1 is a side cross-sectional view schematically illustrating a display panel manufacturing apparatus according to an embodiment. [Figure 8]FIG. 8 is a front view schematically showing the upper surface of the manufacturing apparatus shown in FIG. [Figure 9] 9 is a front view showing the shape of the support member shown in FIG. 7 and FIG. 8. [Figure 10] 1 is a flowchart illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment. [Figure 11] 1 is a schematic diagram illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment. [Figure 12] 1 is a schematic diagram illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment. [Figure 13] 1 is a schematic diagram illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment. [Figure 14] 1 is a schematic diagram illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment. [Figure 15] 1 is a schematic diagram illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment. [Figure 16] 10 is a side cross-sectional view schematically illustrating a display panel manufacturing apparatus according to another embodiment. [Figure 17] 17 is a side cross-sectional view showing a micro LED transfer method using the display panel manufacturing apparatus of FIG. 16. [Figure 18] 10 is a side cross-sectional view schematically illustrating a display panel manufacturing apparatus according to another embodiment. [Figure 19] FIG. 18 is a side cross-sectional view showing a micro LED transfer method using a display panel manufacturing device. [Figure 20] 10 is a side cross-sectional view schematically illustrating a display panel manufacturing apparatus according to another embodiment. [Figure 21] 21 is a side cross-sectional view showing a micro LED transfer method using the display panel manufacturing apparatus of FIG. 20. DETAILED DESCRIPTION OF THE INVENTION

[0032] The advantages and features of the present invention, as well as methods for achieving them, will become clearer with reference to the following detailed embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and can be realized in various different forms. The present embodiments are provided solely for the purpose of complete disclosure of the present invention and to fully convey the scope of the invention to those skilled in the art to which the present invention pertains. The present invention is defined solely by the scope of the claims.

[0033] When elements or layers are referred to as being "on" other elements or layers, this includes cases where other layers or elements are interposed immediately on or between the other elements. The same reference numerals refer to the same components throughout the specification. The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments are merely examples, and the present invention is not limited to the details shown.

[0034] Although terms such as "first" and "second" are used to describe various components, it is understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, it is understood that a "first" component referred to below may be a "second" component within the technical concept of the present invention.

[0035] The features of the various embodiments of the present invention may be partially or wholly combined or combined with one another, and may be technically interlocked and driven in various ways, and the embodiments may be implemented independently of one another or in conjunction with one another.

[0036] Hereinafter, specific embodiments will be described with reference to the accompanying drawings.

[0037] FIG. 1 is a plan view of a display device according to an embodiment.

[0038] 1, a display device 10 according to an embodiment may be applied to various home appliances or Internet of Things devices, such as smartphones, mobile phones, tablet PCs, personal digital assistants (PDAs), portable multimedia players (PMPs), televisions, game consoles, wristwatch-type electronic devices, head-mounted displays, personal computer monitors, laptops, vehicle navigation systems, vehicle dashboards, digital cameras, camcorders, digital billboards, electronic displays, medical devices, testing devices, refrigerators, and washing machines. In this specification, a television (TV) will be described as an example of a display device. The television (TV) may have high resolution or ultra-high resolution, such as HD, UHD, 4K, or 8K.

[0039] Furthermore, the display device 10 according to an embodiment can be classified into various types depending on the display method. For example, display devices can be classified into organic light-emitting display devices (OLEDs), inorganic light-emitting display devices (inorganic ELs), quantum dot light-emitting display devices (QEDs), micro-LED displays (micro-LEDs), nano-LED displays (nano-LEDs), plasma display devices (PDPs), field emission displays (FEDs), cathode ray tube displays (CRTs), liquid crystal displays (LCDs), electrophoretic display devices (EPDs), etc. In the following description, a micro-LED display device will be used as an example of a display device, and unless otherwise specified, the micro-LED display device applied to the embodiment will be simply referred to as a display device. However, the embodiment is not limited to a micro-LED display device, and other display devices listed above or known in the art may also be applied within the scope of sharing the technical concept.

[0040] In the drawings below, the first direction DR1 refers to the horizontal direction of the display device 10, the second direction DR2 refers to the vertical direction of the display device 10, and the third direction DR3 refers to the thickness direction of the display device 10. In this case, "left," "right," "upper," and "lower" refer to directions when the display device 10 is viewed from above. For example, the "right side" refers to one side in the first direction DR1, the "left side" refers to the other side in the first direction DR1, the "upper side" refers to one side in the second direction DR2, and the "lower side" refers to the other side in the second direction DR2. Furthermore, the "upper" and "front" refer to one side in the third direction DR3, and the "lower" and "rear" refer to the other side in the third direction DR3.

[0041] The display device 10 according to an embodiment may have a circular, oval, or square shape in plan view, for example, a square shape. Furthermore, if the display device 10 is a television, it may have a rectangular shape with its long side oriented horizontally. However, the display device 10 is not limited thereto, and may have its long side oriented vertically or may be rotatably installed so that its long side can be variably oriented horizontally or vertically.

[0042] The display device 10 may include a display area DPA and a non-display area NDA. The display area DPA may be an active area where an image is displayed. The display area DPA may have a square shape in plan view, similar to the general shape of the display device 10, but is not limited to this, and may also have a circular or elliptical shape.

[0043] The display area DPA may include a plurality of pixels PX. The plurality of pixels PX may be arranged in a row and column direction. The shape of each pixel PX may be, but is not limited to, a rectangle or a square in plan view, and may also be a rhombus shape with each side tilted relative to one side of the display device 10. The plurality of pixels PX may include a plurality of color pixels PX. For example, but is not limited to, the plurality of pixels PX may include a first color pixel PX of red, a second color pixel PX of green, and a third color pixel PX of blue. The color pixels PX may be arranged alternately in a stripe type or a pentile type.

[0044] The non-display area NDA is disposed around the periphery of the display area DPA. The non-display area NDA may completely or partially surround the display area DPA. The display area DPA may have various shapes, such as a circle or a square. The non-display area NDA may be formed in a shape that surrounds the periphery of the display area DPA. The non-display area NDA may be configured as a bezel of the display device 10.

[0045] In the non-display area NDA, a driving circuit and a driving element for driving the display area DPA may be arranged. In one embodiment, in the non-display area NDA arranged adjacent to the first side (the bottom side in FIG. 1 ) of the display device 10, a pad section is provided on the display substrate of the display device 10, and an external device EXD is mounted on the pad electrodes of the pad section. Examples of the external device EXD include a connection film, a printed circuit board, a driving chip DIC, a connector, and a wiring connection film. In the non-display area NDA arranged adjacent to the second side (the left side in FIG. 1 ) of the display device 10, a scan driver SDR formed directly on the display substrate of the display device 10 may be arranged.

[0046] FIG. 2 is a plan view schematically illustrating a light-emitting region of each pixel according to an embodiment.

[0047] 2, the pixels PX may be arranged in rows and columns and may be divided into a first color pixel PX (red), a second color pixel PX (green), and a third color pixel PX (blue). The pixels PX may also include a fourth color pixel PX (white).

[0048] The pixel electrode of the first-color pixel PX is located in the first light-emitting area EA1 but may extend at least partially into the non-light-emitting area NEA. The pixel electrode of the second-color pixel PX is located in the second light-emitting area EA2 but may extend at least partially into the non-light-emitting area NEA. The pixel electrode of the third-color pixel PX is located in the third light-emitting area EA3 but may extend at least partially into the non-light-emitting area NEA. The pixel electrode of each pixel PX may be connected to one of the switching elements included in the corresponding pixel circuit through at least one insulating layer.

[0049] A plurality of light-emitting elements LE are disposed on the pixel electrodes of the first light-emitting region EA1, the second light-emitting region EA2, and the third light-emitting region EA3. Here, each light-emitting element LE may be formed of a micro LED. The light-emitting elements LE may be disposed in each of the first light-emitting region EA1, the second light-emitting region EA2, and the third light-emitting region EA3. A first red color filter, a second green color filter, and a third blue color filter may be disposed on the first light-emitting region EA1, the second light-emitting region EA2, and the third light-emitting region EA3, respectively, on which the plurality of light-emitting elements LE are disposed.

[0050] FIG. 3 is a plan view schematically showing a light-emitting region of each pixel according to another embodiment.

[0051] 3, the shape of each pixel PX is not limited to a rectangle or square in plan view, but may be a rhombus with each side inclined relative to one side of the display device 10 to form a pentile structure. Therefore, in each pixel PX of the pentile structure, the first light-emitting region EA1 of the first color pixel PX, the second light-emitting region EA2 of the second color pixel PX, the third light-emitting region EA3 of the third color pixel PX, and the fourth light-emitting region EA4 of one of the first, second, and third color pixels PX may each be formed in a rhombus shape.

[0052] The first to fourth light-emitting regions EA1 to EA4 of each pixel PX may be formed to have the same or different sizes or planar areas, and the number of light-emitting elements LE formed in each of the first to fourth light-emitting regions EA1 to EA4 may be the same or different.

[0053] The areas of the first light-emitting region EA1, the second light-emitting region EA2, the third light-emitting region EA3, and the fourth light-emitting region EA4 may be substantially the same, but are not limited to this and may be different. The distances between the adjacent first light-emitting region EA1 and the second light-emitting region EA2, the distances between the adjacent second light-emitting region EA2 and the third light-emitting region EA3, the distances between the adjacent first light-emitting region EA1 and the third light-emitting region EA3, and the distances between the adjacent third light-emitting region EA3 and the fourth light-emitting region EA4 may be substantially the same, but may be different. The embodiments of the present specification are not limited thereto.

[0054] Furthermore, the first light-emitting region EA1 emits the first light, the second light-emitting region EA2 emits the second light, and the third light-emitting region EA3 and the fourth light-emitting region EA4 emit the third light, but the embodiments of the present specification are not limited thereto. For example, the first light-emitting region EA1 may emit the second light, the second light-emitting region EA2 may emit the first light, and the third and fourth light-emitting regions EA3 and EA4 may emit the third light. Alternatively, the first light-emitting region EA1 may emit the third light, the second light-emitting region EA2 may emit the second light, and the first and fourth light-emitting regions EA1 and EA4 may emit the first light. Alternatively, at least one of the first to fourth light-emitting regions EA1 to EA4 may emit the fourth light. The fourth light may be light in the yellow wavelength band. That is, the main peak wavelength of the fourth light may be approximately 550 nm to 600 nm, but the embodiments of the present specification are not limited thereto.

[0055] Fig. 4 is a cross-sectional view according to one embodiment, schematically showing a cross section taken along line A-A' in Fig. 2. Fig. 5 is an enlarged view schematically showing the first light-emitting region in Fig. 4, and Fig. 6 is a cross-sectional view specifically showing the light-emitting element in Fig. 5.

[0056] 4 to 6, the display panel of the display device 10 may include a display substrate 20 and a wavelength conversion unit 30 disposed on the display substrate 20.

[0057] A barrier film BR is disposed on a first substrate 110 of the display substrate 20. The first substrate 110 is made of an insulating material such as a polymer resin. For example, the first substrate 110 is made of polyimide. The first substrate 110 may be a flexible substrate that allows bending, folding, rolling, etc.

[0058] The barrier film BR is a film for protecting the thin film transistors T1, T2, and T3 and the light emitting element LEP from moisture that may penetrate through the first substrate 110, which is susceptible to moisture permeation. The barrier film BR is made of a plurality of inorganic films that are alternately stacked. For example, the barrier film BR may be formed as a multi-layer film (laminate film) in which one or more inorganic films selected from the group consisting of silicon nitride layers, silicon oxynitride layers, silicon oxide layers, titanium oxide layers, and aluminum oxide layers are alternately stacked.

[0059] The transistors T1, T2, and T3 are disposed on the barrier film BR. Each of the thin film transistors T1, T2, and T3 includes an active layer ACT1, a gate electrode G1, a source electrode S1, and a drain electrode D1.

[0060] The active layer ACT1, source electrode S1, and drain electrode D1 of the thin film transistors T1, T2, and T3 are disposed on the barrier film BR. The active layer ACT1 of the thin film transistors T1, T2, and T3 includes polycrystalline silicon, single-crystal silicon, low-temperature polycrystalline silicon, amorphous silicon, or an oxide semiconductor. The active layer ACT1 overlapping with the gate electrode G1 in the third direction (Z-axis direction), which is the thickness direction of the first substrate 110, can be defined as a channel region. The source electrode S1 and the drain electrode D1 are regions that do not overlap with the gate electrode G1 in the third direction (Z-axis direction), and can be conductive by doping ions or impurities into the silicon semiconductor or oxide semiconductor.

[0061] A gate insulating layer 130 is disposed on the active layer ACT1, source electrode S1, and drain electrode D1 of the thin film transistors T1, T2, and T3. The gate insulating layer 130 may be formed of an inorganic film, such as a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0062] A gate electrode G1 of the thin film transistors T1, T2, and T3 is disposed on the gate insulating layer 130. The gate electrode G1 may overlap the active layer ACT1 in the third direction (Z-axis direction). The gate electrode G1 may be formed as a single layer or multiple layers made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0063] A first interlayer insulating film 141 is disposed on the gate electrodes G1 of the thin film transistors T1, T2, and T3. The first interlayer insulating film 141 may be formed of an inorganic film, such as a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The first interlayer insulating film 141 may be formed of a plurality of inorganic films.

[0064] A capacitor electrode CAE is disposed on the first interlayer insulating film 141. The capacitor electrode CAE may overlap the gate electrodes G1 of the thin film transistors T1, T2, and T3 in the third direction (Z-axis direction). Because the first interlayer insulating film 141 has a predetermined dielectric constant, a capacitor may be formed by the capacitor electrode CAE, the gate electrodes G1, and the first interlayer insulating film 141 disposed therebetween. The capacitor electrode CAE may be formed of a single layer or multiple layers made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0065] A second interlayer insulating film 142 is disposed on the capacitor electrode CAE. The second interlayer insulating film 142 may be formed of an inorganic film, such as a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The second interlayer insulating film 142 may be formed of multiple inorganic films.

[0066] A first anode connecting electrode ANDE1 is disposed on the second interlayer insulating film 142. The first anode connecting electrode ANDE1 may be connected to the drain electrode D1 of the thin film transistor T1 through a first connection contact hole that penetrates the gate insulating layer 130, the first interlayer insulating film 141, and the second interlayer insulating film 142. The first anode connecting electrode ANDE1 may be formed of a single layer or multiple layers made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0067] A first planarization film 160 for planarizing steps caused by the thin film transistors T1, T2, and T3 is disposed on the first anode connecting electrode ANDE1. The first planarization film 160 may be formed of an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0068] A second anode connecting electrode ANDE2 is disposed on the first planarization film 160. The second anode connecting electrode ANDE2 may be connected to the first anode connecting electrode ANDE1 via a second connection contact hole penetrating the first planarization film 160. The second anode connecting electrode ANDE2 may be formed of a single layer or multiple layers made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0069] A second planarization film 180 is disposed on the second anode connecting electrode ANDE2. The second planarization film 180 may be formed of an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0070] The light emitting element portion LEP is formed on the second planarization layer 180. The light emitting element portion LEP may include a plurality of pixel electrodes PE1, PE2, and PE3, a plurality of light emitting elements LE, and a common electrode CE.

[0071] The pixel electrodes PE1, PE2, and PE3 may include a first pixel electrode PE1, a second pixel electrode PE2, and a third pixel electrode PE3. The first pixel electrode PE1, the second pixel electrode PE2, and the third pixel electrode PE3 may serve as first electrodes of the light-emitting element LE and may be anode electrodes or cathode electrodes. The first pixel electrode PE1 is located in the first light-emitting area EA1 but may extend at least partially into the non-light-emitting area NEA. The second pixel electrode PE2 is located in the second light-emitting area EA2 but may extend at least partially into the non-light-emitting area NEA. The third pixel electrode PE3 is located in the third light-emitting area EA3 but may extend at least partially into the non-light-emitting area NEA. The first pixel electrode PE1 may be connected to the first switching element T1 through the insulating layer 130, the second pixel electrode PE2 may be connected to the second switching element T2 through the insulating layer 130, and the third pixel electrode PE3 may be connected to the third switching element T3 through the insulating layer 130.

[0072] The first pixel electrode PE1, the second pixel electrode PE2, and the third pixel electrode PE3 may be reflective electrodes. The first pixel electrode PE1, the second pixel electrode PE2, and the third pixel electrode PE3 may be made of Ti (Titanium), copper (Cu), or an alloy of Ti (Titanium) and copper (Cu). They may also have a stacked film structure of Ti (Titanium) and copper (Cu). In addition, the first pixel electrode PE1, the second pixel electrode PE2, and the third pixel electrode PE3 may have a stacked film structure in which a high work function material layer, such as titanium oxide (TiO2), indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), or magnesium oxide (MgO), and a reflective material layer, such as silver (Ag), magnesium (Mg), aluminum (Al), platinum (Pt), lead (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium (Li), calcium (Ca), titanium (Ti), copper (Cu), or a mixture thereof, are stacked. The high work function material layer may be disposed above the reflective material layer and adjacent to the light emitting element LE. The first pixel electrode PE1, the second pixel electrode PE2, and the third pixel electrode PE3 may have a multilayer structure such as ITO / Mg, ITO / MgF, ITO / Ag, or ITO / Ag / ITO, but are not limited thereto.

[0073] A bank BNL is located on the first pixel electrode PE1, the second pixel electrode PE2, and the third pixel electrode PE3. The bank BNL may include an opening exposing the first pixel electrode PE1, an opening exposing the second pixel electrode PE2, and an opening exposing the third pixel electrode PE3, and may define a first light-emitting region EA1, a second light-emitting region EA2, a third light-emitting region EA3, and a non-light-emitting region NEA. That is, the exposed region of the first pixel electrode PE1 that is not covered by the bank BNL may be the first light-emitting region EA1. The exposed region of the second pixel electrode PE2 that is not covered by the bank BNL may be the second light-emitting region EA2. The exposed region of the third pixel electrode PE3 that is not covered by the bank BNL may be the third light-emitting region EA3. The other region where the bank BNL is located may be the non-light-emitting region NEA.

[0074] The bank BNL may include an organic insulating material, such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, a polyimide resin, an unsaturated polyester resin, a polyphenylene resin, a polyphenylene sulfide resin, or benzocyclobutene (BCB).

[0075] In one embodiment, the bank BNL may overlap the color filters CF1, CF2, and CF3 and the light-blocking member BK of the wavelength converting unit 30, which will be described later. In an exemplary embodiment, the bank BNL may completely overlap the light-blocking member BK. The bank BNL may also overlap the first color filter CF1, the second color filter CF2, and the third color filter CF3.

[0076] A plurality of light-emitting elements LE are arranged on the first pixel electrode PE1, the second pixel electrode PE2, and the third pixel electrode PE3.

[0077] As shown in FIGS. 5 and 6, the light-emitting element LE is disposed in each of the first light-emitting region EA1, the second light-emitting region EA2, and the third light-emitting region EA3. The light-emitting element LE may be a vertical light-emitting diode element extending in the third direction DR3. That is, the length of the light-emitting element LE in the third direction DR3 may be longer than the length in the horizontal direction. The horizontal length refers to the length in the first direction DR1 or the length in the second direction DR2. For example, the length of the light-emitting element LE in the third direction DR3 may be approximately 1 to 5 μm.

[0078] Each light-emitting element LE may be a micro LED (micro light-emitting diode). The light-emitting element LE may include a connection electrode 125, a first semiconductor layer SEM1, an electron blocking layer EBL, an active layer MQW, a superlattice layer SLT, a second semiconductor layer SEM2, and a third semiconductor layer SEM3 in the thickness direction of the display substrate 20, i.e., in the third direction DR3. The connection electrode 125, the first semiconductor layer SEM1, the electron blocking layer EBL, the active layer MQW, the superlattice layer SLT, the second semiconductor layer SEM2, and the third semiconductor layer SEM3 may be sequentially stacked in the third direction DR3.

[0079] The light emitting element LE may have a cylindrical, disc, bridge, or rod shape in which the width is longer than the height, but is not limited thereto, and may have various shapes such as a rod, wire, tube, or polygonal prism shape such as a regular cube, rectangular parallelepiped, or hexagonal prism, or a shape extending in one direction with a partially inclined outer surface.

[0080] The connection electrode 125 is disposed on each of the pixel electrodes PE1, PE2, and PE3. In the following, the light emitting element LE disposed on the first pixel electrode PE1 will be described as an example.

[0081] The connection electrode 125 may be attached to the first pixel electrode PE1 and serve to apply a light-emitting signal to the light-emitting element LE. The connection electrode 125 may be an ohmic connection electrode. However, without being limited thereto, it may also be a Schottky connection electrode. The light-emitting element LE may include at least one connection electrode 125. Although FIGS. 7 and 8 show the light-emitting element LE including one connection electrode 125, this is not limiting. In some cases, the light-emitting element LE may include more connection electrodes 125 or may omit the connection electrodes 125. The description of the light-emitting element LE described below is equally applicable to cases where the number of connection electrodes 125 is changed or other structures are further included.

[0082] In the display device 10 according to an embodiment, when the light emitting element LE is electrically connected to the first pixel electrode PE1, the connection electrode 125 can reduce resistance between the light emitting element LE and the first pixel electrode PE1 and improve adhesion. The connection electrode 125 can include a conductive metal oxide. For example, the connection electrode 125 can be made of ITO. The connection electrode 125 is in direct contact with the underlying first pixel electrode PE1 and is therefore made of the same material as the first pixel electrode PE1. The connection electrode 125 can also optionally include a reflective electrode made of a metal material with high reflectivity, such as aluminum (Al), or a diffusion barrier layer containing nickel (Ni). This can improve adhesion between the connection electrode 125 and the first pixel electrode PE1, thereby improving contact characteristics.

[0083] 6, in an exemplary embodiment, the first pixel electrode PE1 may include a lower electrode layer P1, a reflective layer P2, and an upper electrode layer P3. The lower electrode layer P1 may be disposed at the bottom of the first pixel electrode PE1 and electrically connected to the switching element. The lower electrode layer P1 may include a metal oxide, such as titanium oxide (TiO2), indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), or magnesium oxide (MgO).

[0084] The reflective layer P2 is disposed on the lower electrode layer P1 and reflects the light emitted from the light-emitting element LE upward. The reflective layer P2 may include a metal with high reflectivity, such as silver (Ag), magnesium (Mg), aluminum (Al), platinum (Pt), lead (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium (Li), calcium (Ca), or a mixture thereof.

[0085] The upper electrode layer P3 is disposed on the reflective layer P2 and may be in direct contact with the light-emitting element LE. The upper electrode layer P3 is disposed between the reflective layer P2 and the connection electrode 125 of the light-emitting element LE and may be in direct contact with the connection electrode 125. As described above, the connection electrode 125 is made of a metal oxide, and the upper electrode layer P3 may also be made of a metal oxide, just like the connection electrode 125.

[0086] The upper electrode layer P3 may be formed of titanium (Ti), copper (Cu), or an alloy of titanium and copper (Cu). It may also have a stacked film structure of titanium and copper (Cu). The upper electrode layer P3 may also include titanium oxide (TiO2), indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), or magnesium oxide (MgO). In an exemplary embodiment, if the connection electrode 125 is made of ITO, the first pixel electrode PE1 may have a multilayer structure of ITO / Ag / ITO.

[0087] The first semiconductor layer SEM1 is disposed on the connection electrode 125. The first semiconductor layer SEM1 may be a p-type semiconductor and may include a semiconductor material having a chemical formula of AlxGayIn1-x-yN (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, the first semiconductor layer SEM1 may be one or more of p-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The first semiconductor layer SEM1 may be doped with a p-type dopant, and the p-type dopant may be Mg, Zn, Ca, Se, Ba, or the like. For example, the first semiconductor layer SEM1 may be p-GaN doped with p-type Mg. The thickness of the first semiconductor layer SEM1 may be in the range of 30 nm to 200 nm, but is not limited thereto.

[0088] The electron blocking layer EBL is disposed on the first semiconductor layer SEM1. The electron blocking layer EBL may be a layer for suppressing or preventing excessive electrons from flowing into the active layer MQW. For example, the electron blocking layer EBL may be p-AlGaN doped with p-type Mg. The thickness of the electron blocking layer EBL may be in the range of 10 nm to 50 nm, but is not limited thereto. Alternatively, the electron blocking layer EBL may be omitted.

[0089] The active layer MQW is disposed on the electron blocking layer EBL and can emit light by recombination of electron-hole pairs in response to an electrical signal applied via the first semiconductor layer SEM1 and the second semiconductor layer SEM2.

[0090] The active layer MQW may include a material with a single or multiple quantum well structure. When the active layer MQW includes a material with a multiple quantum well structure, it may have a structure in which multiple well layers and barrier layers are alternately stacked. In this case, the well layers may be made of InGaN, and the barrier layers may be made of GaN or AlGaN, but are not limited thereto. The thickness of the well layers may be approximately 1 to 4 nm, and the thickness of the barrier layers may be 3 to 10 nm.

[0091] Alternatively, the active layer MQW may have a structure in which semiconductor materials with large band gap energy and semiconductor materials with small band gap energy are alternately stacked, and may include different Group III to V semiconductor materials depending on the wavelength band of the emitted light. The light emitted by the active layer MQW is not limited to the first light, and may also emit the second light (light in the green wavelength band) or the third light (light in the red wavelength band) depending on the case.

[0092] Specifically, the color of light emitted by the active layer MQW can change depending on the indium (In) content. For example, as the indium (In) content decreases, the wavelength band of the light emitted by the active layer shifts toward the red wavelength band, and as the indium (In) content increases, the wavelength band of the light emitted shifts toward the blue wavelength band. For example, when the indium (In) content is 15% or less, the active layer MQW can emit first light in the red wavelength band with a main peak wavelength ranging from approximately 600 nm to 750 nm. Alternatively, when the indium (In) content is 25%, the active layer MQW can emit second light in the green wavelength band with a main peak wavelength ranging from approximately 480 nm to 560 nm. Furthermore, when the indium (In) content is 35% or more, the active layer MQW can emit third light in the blue wavelength band with a main peak wavelength ranging from approximately 370 nm to 460 nm. With reference to FIG. 6, an example will be described in which the active layer MQW emits light in the blue wavelength band having a main peak wavelength in the range of approximately 370 nm to 460 nm.

[0093] A superlattice layer SLT is disposed on the active layer MQW. The superlattice layer SLT may be a layer for relieving stress between the second semiconductor layer SEM2 and the active layer MQW. For example, the superlattice layer SLT may be formed of InGaN or GaN. The thickness of the superlattice layer SLT may be approximately 50 to 200 nm. The superlattice layer SLT may be omitted.

[0094] The second semiconductor layer SEM2 is disposed on the superlattice layer SLT. The second semiconductor layer SEM2 may be an n-type semiconductor. The second semiconductor layer SEM2 may include a semiconductor material having a chemical formula of AlxGayIn1-x-yN (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, the second semiconductor layer SEM2 may be one or more of n-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The second semiconductor layer SEM2 may be doped with an n-type dopant, and the n-type dopant may be Si, Ge, Sn, or the like. For example, the second semiconductor layer SEM2 may be n-GaN doped with n-type Si. The thickness of the second semiconductor layer SEM2 may be in the range of 2 μm to 4 μm, but is not limited thereto.

[0095] The third semiconductor layer SEM3 is disposed on the second semiconductor layer SEM2. The third semiconductor layer SEM3 is disposed between the second semiconductor layer SEM2 and the common electrode CE. The third semiconductor layer SEM3 may be an undoped semiconductor. The third semiconductor layer SEM3 may include the same material as the second semiconductor layer SEM2 and may be a material that is not doped with an n-type or p-type dopant. In an exemplary embodiment, the third semiconductor layer SEM3 may be at least one of undoped InAlGaN, GaN, AlGaN, InGaN, AlN, and InN, but is not limited to these.

[0096] A planarization layer PLL is disposed on the bank BNL and the plurality of pixel electrodes PE1, PE2, and PE3. The planarization layer PLL can planarize the lower step so that a common electrode CE (described later) can be formed. The planarization layer PLL can be formed to a predetermined height so that at least a portion, for example, the upper portions, of the plurality of light-emitting elements LE can protrude above the planarization layer PLL. That is, the height of the planarization layer PLL based on the top surface of the first pixel electrode PE1 may be smaller than the height of the light-emitting elements LE.

[0097] The planarization layer PLL may include an organic material to planarize the lower step. For example, the planarization layer PLL may include an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, a polyimide resin, an unsaturated polyester resin, a polyphenylene resin, a polyphenylene sulfide resin, or benzocyclobutene (BCB).

[0098] A common electrode CE is disposed on the planarization layer PLL and the plurality of light-emitting elements LE. Specifically, the common electrode CE is disposed on one surface of the first substrate 110 on which the light-emitting elements LE are formed, and may be disposed throughout the display area DA and the non-display area NDA. The common electrode CE is disposed in the display area DA so as to overlap with each of the light-emitting areas EA1, EA2, and EA3, and has a thin thickness so as to allow light to be emitted.

[0099] The common electrode CE may be disposed directly on the top and side surfaces of the light-emitting elements LE. The common electrode CE may be in direct contact with the second semiconductor layer SEM2 and the third semiconductor layer SEM3 on the side surfaces of the light-emitting elements LE. As shown in FIG. 6, the common electrode CE may be a common layer that covers the light-emitting elements LE and connects the light-emitting elements LE in common. The conductive second semiconductor layer SEM2 has a patterned structure for each of the light-emitting elements LE, so that the common electrode CE may be in direct contact with the side surfaces of the second semiconductor layer SEM2 of each light-emitting element LE so that a common voltage is applied to each light-emitting element LE.

[0100] The common electrode CE is disposed over the entire first substrate 110 and receives a common voltage, and therefore may include a material having low resistance. The common electrode CE may also be formed to a thin thickness to facilitate light transmission. For example, the common electrode CE may include a material having low resistance, such as aluminum (Al), silver (Ag), or copper (Cu). The thickness of the common electrode CE may be, but is not limited to, approximately 10 Å to 200 Å.

[0101] The light emitting element LE described above receives a pixel voltage or an anode voltage from the pixel electrode via the connection electrode 125, and receives a common voltage via the common electrode CE. The light emitting element LE can emit light at a certain brightness according to the voltage difference between the pixel voltage and the common voltage.

[0102] In this embodiment, by arranging multiple light-emitting elements LE, i.e., inorganic light-emitting diodes, on the pixel electrodes PE1, PE2, and PE3, it is possible to eliminate the drawbacks of organic light-emitting diodes, which are vulnerable to external moisture and oxygen, and improve the lifespan and reliability.

[0103] The wavelength conversion section 30 may be disposed on the light emitting element section LEP. The wavelength conversion section 30 may include a partition wall PW, a wavelength conversion layer, a color filter, a light blocking member BK, and a protective layer PTL.

[0104] The partition walls PW are disposed on the common electrode CE in the display area DPA and, together with the banks BNL, partition the display area DPA into a plurality of light-emitting areas EA1, EA2, and EA3. The partition walls PW are disposed to extend in the first direction DR1 and the second direction DR2 and are formed in a grid pattern across the entire display area DA. The partition walls PW do not overlap the light-emitting areas EA1, EA2, and EA3, but may overlap the non-light-emitting area NEA.

[0105] The partition wall PW may include a plurality of openings OP1, OP2, and OP3 exposing the underlying common electrode CE. The plurality of openings OP1, OP2, and OP3 may include a first opening OP1 overlapping the first light-emitting region EA1, a second opening OP2 overlapping the second light-emitting region EA2, and a third opening OP3 overlapping the third light-emitting region EA3. Here, the plurality of openings OP1, OP2, and OP3 correspond to the plurality of light-emitting regions EA1, EA2, and EA3. That is, the first opening OP1 corresponds to the first light-emitting region EA1, the second opening OP2 corresponds to the second light-emitting region EA2, and the third opening OP3 corresponds to the third light-emitting region EA3.

[0106] The partition walls PW may provide a space for the first and second wavelength conversion layers to be formed. To this end, the partition walls PW may have a predetermined thickness, e.g., a thickness of 1 μm to 10 μm. The partition walls PW may include an organic insulating material to achieve the predetermined thickness. Examples of the organic insulating material include an epoxy resin, an acrylic resin, a cardo resin, or an imide resin.

[0107] The first wavelength conversion layers are disposed in the first openings OP1. The first wavelength conversion layers are formed of a pattern of spaced apart dot-shaped islands. The first wavelength conversion layers may include a first base resin and first wavelength conversion particles. The first base resin may include a light-transmitting organic material. For example, the first base resin may include an epoxy-based resin, an acrylic-based resin, a cardo-based resin, or an imide-based resin. The first wavelength conversion particles may be quantum dots (QDs), quantum rods, fluorescent materials, or phosphorescent materials. For example, quantum dots may be particulate materials that emit a specific color as electrons transition from the conduction band to the valence band.

[0108] The quantum dots may be semiconductor nanocrystal materials. The quantum dots have a specific band gap depending on their composition and size, and can absorb light and then emit light with a specific wavelength. Examples of the semiconductor nanocrystals of the quantum dots include group IV nanocrystals, group II-VI compound nanocrystals, group III-V compound nanocrystals, group IV-VI nanocrystals, or combinations thereof.

[0109] The first wavelength conversion layer is formed in the first opening OP1 of the first light-emitting area EA1. The first wavelength conversion layer can convert or shift the peak wavelength of incident light to light with another specific peak wavelength and then emit the light. The first wavelength conversion layer can convert a portion of the blue light emitted from the light-emitting element LE into light similar to red, which is the first light. The first wavelength conversion layer can emit light similar to red, which can be converted into the red light, which is the first light, via the first color filter.

[0110] The second wavelength conversion layers are disposed in the second openings OP2. The second wavelength conversion layers are formed of a pattern of dot-shaped islands spaced apart from each other. For example, the second wavelength conversion layers are disposed overlapping the second light-emitting regions EA2. The second wavelength conversion layers may include a second base resin and second wavelength-converting particles. The second base resin may include a light-transmitting organic material. Therefore, the second wavelength conversion layers can convert or shift the peak wavelength of incident light to light with another specific peak wavelength and then emit the light. The second wavelength conversion layers can convert a portion of the blue light emitted from the light-emitting elements LE into light similar to green, which is the second light. The second wavelength conversion layer can emit light similar to green, which can be converted into red light, which is the first light, via the second color filter.

[0111] In the third light-emitting area EA3, only a transparent light-transmitting organic material is formed in the third opening OP3, allowing the blue light emitted from the light-emitting element LE to be emitted as it is through the third color filter.

[0112] The plurality of color filters are disposed on the partition wall PW and the first and second wavelength conversion layers. The plurality of color filters are disposed to overlap the plurality of openings OP1, OP2, OP3 and the first and second wavelength conversion layers. The plurality of color filters may include a first color filter, a second color filter, and a third color filter.

[0113] The first color filter is disposed overlapping the first light-emitting region EA1. The first color filter is also disposed overlapping the first opening OP1 on the first opening OP1 of the partition wall PW. The first color filter transmits the first light emitted from the light-emitting element LE and absorbs or blocks the second light and the third light. For example, the first color filter can transmit light in the blue wavelength band and absorb or block light in other wavelength bands such as green and red.

[0114] The second color filter is disposed overlapping the second light-emitting region EA2. The second color filter may also be disposed overlapping the second opening OP2 on the second opening OP2 of the partition wall PW. The second color filter can transmit the second light and absorb or block the first and third lights. For example, the second color filter can transmit light in the green wavelength band and absorb or block light in other wavelength bands such as blue and red.

[0115] The third color filter is disposed overlapping the third light-emitting region EA3. The third color filter is also disposed on the third opening OP3 of the partition wall PW and overlapping the third opening OP3. The third color filter transmits the third light and absorbs or blocks the first and second lights. For example, the third color filter transmits light in the red wavelength band and absorbs or blocks light in other wavelength bands such as blue and green.

[0116] The planar area of ​​each of the plurality of color filters may be larger than the planar area of ​​each of the plurality of light-emitting areas EA1, EA2, and EA3. For example, the first color filter may be larger than the planar area of ​​the first light-emitting area EA1. The second color filter may be larger than the planar area of ​​the second light-emitting area EA2. The third color filter may be larger than the planar area of ​​the third light-emitting area EA3. However, without being limited thereto, the planar area of ​​each of the plurality of color filters may be the same as the planar area of ​​each of the plurality of light-emitting areas EA1, EA2, and EA3.

[0117] Referring to Figure 5, light-shielding members BK are disposed on the partition walls PW. The light-shielding members BK overlap the non-light-emitting areas NEA to block light transmission. The light-shielding members BK can be disposed in a roughly lattice pattern on a plane, similar to the banks BNL or the partition walls PW. The light-shielding members BK are disposed to overlap the banks BNL and the partition walls PW, but do not overlap the light-emitting areas EA1, EA2, and EA3.

[0118] In one embodiment, the light blocking member BK may include an organic light blocking material and may be formed by coating the organic light blocking material and exposing it to light. The light blocking member BK may include a dye or pigment having light blocking properties and may be a black matrix. At least a portion of the light blocking member BK may overlap an adjacent color filter, and the color filter may be disposed on at least a portion of the light blocking member BK.

[0119] A protective layer PTL may be disposed on the plurality of color filters CF1, CF2, and CF3 and the light blocking member BK. The first protective layer PTL may be disposed on the top of the display device 10 and may protect the plurality of color filters and the light blocking member BK below. One surface of the protective layer PTL, for example, the lower surface, may be in contact with the upper surfaces of the plurality of color filters and the light blocking member BK, respectively.

[0120] The protective layer PTL may include an inorganic insulating material to protect the color filters and the light blocking member BK. For example, the first protective layer PTL may include, but is not limited to, silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), aluminum oxide (AlxOy), aluminum nitride (AlN), etc. The first protective layer PTL has a predetermined thickness, for example, but not limited to, in the range of 0.01 to 1 μm.

[0121] Hereinafter, a display panel manufacturing apparatus that pressurizes and attaches a plurality of light-emitting elements LE, i.e., micro LEDs, arranged on the pixel electrodes PE1, PE2, and PE3 of the display substrate 20 will be specifically described.

[0122] 7 is a side cross-sectional view schematically illustrating an apparatus for manufacturing a display panel according to an embodiment, and FIG. 8 is a front view schematically illustrating an upper surface of the apparatus shown in FIG.

[0123] 7 and 8, a display panel manufacturing apparatus can bond two or more bonding targets to each other using a laser beam. The bonding targets can be bonded together and electrically connected. The bonding targets can be a substrate, a film, a display panel, a touch panel, a printed circuit board, a flexible circuit board, or a semiconductor element such as a light-emitting element. In the following, an example will be described in which the first bonding target is a display substrate 20 and the second bonding target is a light-emitting element LE. The display substrate 20 is a substrate onto which the light-emitting element LE is transferred and can be referred to as a target substrate. Furthermore, multiple light-emitting elements LE can be disposed on a donor substrate TSUB and then transferred to the target substrate. The donor substrate TSUB is made of a transparent material that allows light to pass through. For example, the donor substrate TSUB can include a transparent polymer such as polyimide, polyester, polyacrylic, polyepoxy, polyethylene, polystyrene, or polyethylene terephthalate. The adhesive layer ADL disposed on one surface of the donor substrate TSUB can include an adhesive material for adhering the multiple light-emitting elements LE. For example, the adhesive material can include urethane acrylate, epoxy acrylate, polyester acrylate, or the like. The donor substrate TSUB may be smaller than the target substrate 20. Multiple donor substrates TSUB may be disposed on the target substrate 20.

[0124] The display panel manufacturing apparatus may include a mounting stage 200 , a pressure unit 300 , and a laser irradiation unit 500 .

[0125] The mounting stage 200 has an upper surface parallel to a plane defined by a first direction DR1 and a second direction DR2 that are perpendicular to each other, and the display substrate 20 having a plurality of light emitting elements LE arranged on the upper surface is mounted thereon.

[0126] The mounting stage 200 may be a loading plate, and may be formed in a polygonal flat plate shape, such as a square or a rectangle. The mounting stage 200 may also be formed in a flat plate shape, such as a circle or an oval. In the following, an example in which the mounting stage 200 is formed in a square flat plate shape will be described. In one embodiment, the mounting stage 200 can fix the display substrate 20.

[0127] The laser irradiation unit 500 is disposed on the front side of the mounting stage 200, which will be described later, and irradiates the display substrate 20 with laser light via the mounting stage 200. The laser irradiation unit 500 may be disposed at the uppermost side of the manufacturing apparatus. The laser irradiation unit 500 irradiates laser light in the direction toward the lower mounting stage 200, and the light irradiated from the laser irradiation unit 500 is applied to a plurality of light-emitting elements LE arranged on the display substrate 20.

[0128] The laser irradiation unit 500 may include a laser light source 510 and an optical system 530 .

[0129] The laser light source 510 is a device capable of generating laser light using energy supplied from an external source, and can be configured to generate laser light from, for example, a solid-state laser such as a YAG laser, a ruby ​​laser, a glass laser, a YVO4 laser, an LD laser, or a fiber laser, a liquid laser such as a dye laser, a CO2 laser, an excimer laser (such as an ArF laser, a KrF laser, an XeCl laser, or an XeF laser), a gas laser such as an Ar laser or a He-Ne laser, a semiconductor laser, or a free electron laser.

[0130] The optical system 530 may include a plurality of lenses. The optical system 530 receives the laser light in the form of a beam from the laser light source 510 and performs optical dispersion to enable area heating for a predetermined area.

[0131] The laser light emitted from the optical system 530 is irradiated onto the light emitting elements LE arranged on the display substrate 20 placed on the mounting stage 200, and can heat predetermined regions of the light emitting elements LE.

[0132] The pressure unit 300 is disposed in front of the mounting stage 200 and spaced apart from the mounting stage 200 in the third direction DR3. The pressure unit 300 may apply pressure to the display substrate 20 and the light emitting element LE on the mounting stage 200.

[0133] The pressure applying section 300 may include a mask member 310 , a first attachment member 315 , a pressure applying member 350 , a support member 380 and a second attachment member 385 .

[0134] The mask member 310 may be formed of multiple layers. The mask member 310 may include a base layer 311 and a light-blocking pattern layer 312. The mask member 310 may further include a protective layer 313 on the light-blocking pattern layer 312, but the protective layer 313 may be omitted. In another variation, the mask member 310 has the base layer 311, the light-blocking pattern layer 312, and the protective layer 313 arranged in this order, but the base layer 311 may also be arranged on top and the protective layer 313 on the bottom.

[0135] The base layer 311 may be formed as a transparent or semi-transparent flat plate, and may include at least one transparent material such as glass, quartz, silicon, etc. The base layer 311 allows laser light to pass through its opposite front and back surfaces.

[0136] The light-shielding pattern layer 312 is disposed on one surface of the base layer 311 and includes a pattern having light-shielding or reflective properties. The thickness of the light-shielding pattern layer 312 is not particularly limited, but may be in the range of 80 nm to 180 nm. If the layer is too thin, it is difficult to obtain the desired light-shielding or reflective properties, and if the layer is too thick, it is difficult to process the light-shielding pattern with high precision.

[0137] The light-shielding pattern layer 312 is not particularly limited as long as it is a material having light-shielding properties, and examples thereof include chromium (Cr), chromium oxynitride (CrON), chromium nitride (CrN), molybdenum silicide oxide (MoSiO), molybdenum silicide oxynitride (MoSiON), tantalum oxide (TaO), tantalum silicide oxide (TaSiO), etc. In one embodiment, chromium (Cr) is selected for the light-shielding pattern layer 312.

[0138] The light-shielding pattern layer 312 includes openings 312-OS. The light-shielding pattern layer 312 is included in the mask member 310, and the openings 312-OS of the light-shielding pattern layer 312 do not overlap with other components of the mask member 310, so they can also be referred to as openings 312-OS of the mask member 310.

[0139] The laser beam passes through the openings 312-OS. Therefore, the openings 312-OS can define a transmission area of ​​the laser beam. Here, the light irradiated from the laser irradiation unit 500 passes through the openings 312-OS corresponding to the display areas DPA of the display substrate 20 by the light-shielding pattern layer 312, and is applied to the plurality of target substrates TSUB.

[0140] The openings 312-OS of the light-shielding pattern layer 312 may overlap the target substrate TSUB.

[0141] The light-shielding pattern layer 312 is disposed so as to face the light-emitting element LE.

[0142] The protective layer 313 is disposed on the base layer 311 on which the light-shielding pattern layer 312 is formed, and protects the surface of the light-shielding pattern layer 312 to prevent damage to the light-shielding pattern. The thickness of the protective layer 313 is not particularly limited, but may be in the range of about 2 to 3 μm. The protective layer 313 includes a transparent material, and may be a transparent or translucent material, for example, a transparent resin.

[0143] The first mounting member 315 may be attached to the rear surface of the outer periphery of the mask member 310. For example, the first mounting member 315 may be attached to the rear surface of the outer periphery of the base layer 311. The first mounting member 315 may include, but is not limited to, any one of an electrostatic chuck, an adhesive chuck, a vacuum chuck, and a porous vacuum chuck. For example, the first mounting member 315 may include a clamp. The first mounting member 315 does not overlap with the path of the laser light.

[0144] The pressure member 350 may include a first light-transmitting plate 351 , a second light-transmitting plate 352 , a gas pressure regulator 353 , a gas conduit 354 , a holding frame 355 and a buffer material 356 .

[0145] The first light-transmitting plate 351 and the second light-transmitting plate 352 are attached to the holding frame 355 so as to overlap in the thickness direction. Therefore, when the holding frame 355 is moved downward, the first light-transmitting plate 351 and the second light-transmitting plate 352 attached to the holding frame 355 also move downward, and can press and apply pressure to the mask member 310 located below.

[0146] A sealed space 350-S is formed between the first light-transmitting plate 351 and the second light-transmitting plate 352.

[0147] The first light-transmitting plate 351 may be formed in a rectangular plane having a long side in a first direction and a short side in a second direction intersecting with the first direction. The corner where the long side in the first direction intersects with the short side in the second direction is a right angle. The planar shapes of the first light-transmitting plate 351 and the second light-transmitting plate 352 are not limited to a rectangle, and may be formed in other polygonal, circular, or elliptical shapes.

[0148] The first light-transmitting plate 351 and the second light-transmitting plate 352 are made of a light-transmitting material, and are capable of transmitting the laser light emitted from the laser irradiation unit 500.

[0149] The first and second light-transmitting plates 351 and 352 may be made of any material that can withstand the pressure inside the sealed space 350-S. The first and second light-transmitting plates 351 and 352 may be made of materials such as tempered glass, quartz, acrylic resin, metal oxide, or semi-metal oxide, such as silicon oxide or aluminum oxide. However, the materials are not limited thereto. For example, the first and second light-transmitting plates 351 and 352 may be made of a silicone resin multilayer, a silicone resin-PET (polyethylene terephthalate) laminate layer, or PDMS (polydimethylsiloxane).

[0150] The second light-transmitting plate 352 generates a pressure force downward, that is, in the direction toward the mask member 310, due to the pressure inside the sealed space 350-S.

[0151] The gas pressure regulator 353 supplies gas to the sealed space 350-S between the first light-transmitting plate 351 and the second light-transmitting plate 352 to generate a pressure.

[0152] The gas pressure regulator 353 can supply a gas that is inert or has very low chemical reactivity and is transparent to a laser beam, such as nitrogen (N), helium (He), neon (Ne), argon (Ar), carbon dioxide (CO), or a mixture thereof, to the sealed space 350-S. Hereinafter, such gases that are inert or have very low chemical reactivity will be collectively referred to as "neutral gas."

[0153] The gas pressure regulator 353 may include a reservoir (particularly a gas tank) for storing gas, a gas pump for pressurizing and supplying the gas, and a gas valve for regulating the flow of the gas. The gas pump may be configured to supply the gas into the enclosed space 350-S at a pressure increased compared to the pressure outside the enclosed space 350-S.

[0154] When the pressure inside the sealed space 350-S is sufficiently high, the gas valve can cut off the supply of gas and close the sealed space 350-S so that the internal pressure of the sealed space 350-S is maintained. The gas valve can be, for example, but is not limited to, a ball valve, a globe valve, a gate valve, a control valve, etc.

[0155] The gas conduit 354 connects the gas pressure regulator 353 and the sealed space 350-S and provides a path for gas to travel. The gas conduit 354 allows gas to travel between the gas pressure regulator 353 and the sealed space 350-S.

[0156] In one embodiment, the gas conduit 354 may be formed to penetrate the holding frame 355. For example, the gas conduit 354 may be formed to penetrate the second light-transmitting plate 352.

[0157] The holding frame 355 fixes both ends of the first light-transmitting plate 351 and the second light-transmitting plate 352 .

[0158] The buffer material 356 is disposed between the second light-transmitting plate 352 and the holding frame 355, and can prevent impact between the second light-transmitting plate 352 and the holding frame 355 when the second light-transmitting plate 352 moves up and down depending on the gas filling state.

[0159] The buffer material 356 may include an O-ring. The buffer material 356 may be made of a polymer, rubber (including a resin elastomer), perfluorinated fluororesin (PTFE, FEP, PFA), or any of a variety of other elastic materials.

[0160] The support member 380 is disposed on the display substrate 20. For example, the support member 380 may be disposed between the display substrate 20 and the mask member 310. The support member 380 has a plurality of openings (380-OS in FIG. 9 ), and a donor substrate TSUB may be disposed in each opening 380-OS. The plurality of openings 380-OS of the support member 380 overlap with the openings 312-OS of the mask member 310, and may overlap with a plurality of donor substrates TSUB.

[0161] The support member 380 can protrude outward beyond the display substrate 20. This allows pressure to be applied evenly across the entire display substrate 20.

[0162] The support member 380 has a height 20-h that is the same as the sum of the thickness Th of the donor substrate TSUB disposed on the display substrate 20 and the height Lh of the light-emitting element LE.

[0163] The support member 380 may be made of a material such as tempered glass, quartz, acrylic resin, metal oxide, or semi-metal oxide (e.g., silicon oxide, aluminum oxide, etc.), but is not limited thereto. For example, the support member 380 may be formed of a silicone resin multilayer, a silicone resin-PET (polyethylene terephthalate) laminate layer, PDMS (polydimethylsiloxane), etc. Furthermore, when the support member 380 is made of a material that can reflect laser light, it may have a function of protecting the display substrate 20 disposed below.

[0164] The second mounting member 385 may be attached to one surface of the outer periphery of the support member 380. For example, the second mounting member 385 may be attached to the back surface of the outer periphery of the support member 380. The second mounting member 385 may include, but is not limited to, any one of an electrostatic chuck, an adhesive chuck, a vacuum chuck, and a porous vacuum chuck. For example, the second mounting member 385 may be a clamp. The second mounting member 385 does not overlap with the path of the laser light.

[0165] FIG. 9 is a front view showing the shape of the support member shown in FIGS.

[0166] 7-9, support member 380 includes openings 380-OS between which target substrate TSUB is positioned.

[0167] The support member 380 may be disposed to overlap the display substrate 20 in an area other than the area where the target substrate TSUB is disposed. Therefore, when the pressure member 350 presses the target substrate TSUB, the support member 380 supports the mask member 310 to prevent the mask member 310 from being deformed.

[0168] Although FIG. 9 shows six target substrates TSUB arranged, this is just an example and does not limit the number or arrangement of the target substrates TSUB.

[0169] 10 is a flowchart illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment. 11 to 15 are schematic diagrams illustrating a micro LED transfer method using a manufacturing apparatus according to an embodiment.

[0170] Hereinafter, a micro LED transfer method will be described with reference to Fig. 10 and Fig. 11 to Fig. 15. The display panel manufacturing apparatus described with reference to Fig. 10 to Fig. 15 may be the manufacturing apparatus for manufacturing the display panel described with reference to Fig. 5 to Fig. 9.

[0171] First, the display substrate 20 is placed on the mounting stage 200 (S110 in FIG. 11).

[0172] Next, a support member 380 and a plurality of donor substrates TSUB are placed on the display substrate 20 (S120 in FIG. 11).

[0173] 11, the support member 380 is placed in front of the display substrate 20, and then moved toward the display substrate 20 to place the support member 380 on the display substrate 20. The support member 380 has a plurality of openings 380-OS as described with reference to FIG.

[0174] 12, a donor substrate TSUB is placed in the openings 380-OS of the support member 380. For example, a first donor substrate TSUB can be placed in the first opening 380-OS and a second donor substrate TSUB can be placed in the second opening 380-OS.

[0175] The length and width of the opening 380-OS of the support member 380 may be the same as or larger than the length and width of the donor substrate TSUB.

[0176] Since the height of the support member 380 is the same as the sum of the thickness of the donor substrate TSUB and the height of the light-emitting element LE, the upper surface of the support member 380 and the upper surface of the donor substrate TSUB can be arranged on a straight line.

[0177] In another embodiment, the light-emitting element LE is transferred onto the display substrate 20, and then the support member 380 can be disposed on the display substrate 20 so as not to overlap with the light-emitting element LE. In this case, too, the height of the support member 380 is the same as the sum of the thickness of the donor substrate TSUB and the height of the light-emitting element LE, so that the upper surface of the support member 380 and the upper surface of the donor substrate TSUB can be disposed on a straight line. Any conventionally known method may be used as a method for transferring the light-emitting element LE.

[0178] Next, the mask member 310 and the pressure member 350 are placed (S130 in FIG. 11).

[0179] 13, the mask member 310 is first placed on the display substrate 20. The openings 312-OS defined by the light-blocking pattern layer 312 of the mask member 310 can be aligned with the openings 380-OS of the support member 380. The openings 312-OS of the mask member 310 can overlap the donor substrate TSUB. The mask member 310 is lighter and more mobile than the pressure member 350, which facilitates alignment and allows for increased accuracy.

[0180] Referring to FIG. 14, the pressure member 350 is disposed on the front side of the mask member 310 and can move in a direction toward the display substrate 20 .

[0181] Next, gas is supplied between the first light-transmitting plate 351 and the second light-transmitting plate 352 in the pressure member 350, and laser is irradiated (S140 in FIG. 11).

[0182] The gas pressure regulator 353 opens the gas valve to fill the sealed space 350-S between the first translucent plate 351 and the second translucent plate 352 with gas through the gas conduit 354. As the sealed space 350-S is filled with gas, the pressure inside the sealed space 350-S increases, causing the second translucent plate 352 to expand downward (toward the bottom), i.e., toward the display substrate 20, generating a downward pressure.

[0183] The second light-transmitting plate 352 moves downward due to the gas filling, and uniform pressure can be applied to the surface of the light-emitting element LE arranged on the display substrate 20. If the first light-transmitting plate 351 presses the display substrate 20 from above the mask member 310 without the second light-transmitting plate 352, thermal deformation of the first light-transmitting plate 351 may occur due to laser light irradiation, which may result in poor pressure uniformity on the display substrate 20.

[0184] The laser irradiation unit 500 irradiates laser light in a direction toward the mask member 310 on the lower surface. Here, the light irradiated from the laser irradiation unit 500 passes through the openings 312-OS defined by the light-shielding pattern layer 312 and the openings 380-OS of the support member 380, and is applied to the plurality of light-emitting elements LE arranged on the display substrate 20. In other words, only the laser light that passes through the openings 312-OS and the openings 380-OS can be applied to the plurality of light-emitting elements LE arranged on the display substrate 20.

[0185] The laser light applied to the light-shielding pattern layer 312 cannot pass through the light-shielding pattern layer 312. Therefore, it is possible to prevent damage to the display substrate 20 that may occur when the laser light is irradiated onto the region NDA other than the donor substrate TSUB where bonding is not required.

[0186] When the laser irradiation by the laser irradiation unit 500 is completed, the gas pressure regulator 353 can discharge the gas in the sealed space 350-S to reduce the pressure in the sealed space 350-S. When the pressure in the sealed space 350-S is reduced, the second light-transmitting plate 352, which has expanded downward, returns to its original state, and the pressure is reduced.

[0187] Thereafter, the plate transport member 320 can move the first light-transmitting plate 351 in a direction away from the display substrate 20 .

[0188] According to one embodiment, even in the case of a display substrate 20 with a large area, uniform pressure distribution is possible when bonding the light emitting elements LE on the display substrate 20 using a laser.

[0189] Furthermore, even in the case of a large-area display substrate 20, the support member 380 supports the second light-transmitting plate 352 outward from the display substrate 20, thereby allowing a uniform pressure to be applied to the display substrate 20.

[0190] FIG. 16 is a side cross-sectional view schematically showing a display panel manufacturing apparatus according to another embodiment, and FIG. 17 is a side cross-sectional view showing a micro LED transfer method using the display panel manufacturing apparatus of FIG.

[0191] 16 and 17, the display panel manufacturing apparatus differs from that described with reference to Figures 7 to 15 in that a mask member 310 is disposed between a pressure member 350 and a laser irradiation unit 500. Descriptions that overlap with the embodiment of Figures 7 to 15 will be omitted.

[0192] 16, the mask member 310 may be formed of multiple layers. The mask member 310 may include a base layer 311 and a light-shielding pattern layer 312. The mask member 310 may further include a protective layer 313 on the light-shielding pattern layer 312, although the protective layer 313 may be omitted.

[0193] The base layer 311 is disposed to face the laser irradiation unit 500. The base layer 311 includes at least one transparent material such as glass, quartz, silicon, etc., and is formed in the shape of a transparent or translucent flat plate. The base layer 311 allows the laser light to pass through its front and back surfaces, which are opposite to each other.

[0194] The base layer 311 has a length and width dimension that can cover the entire display substrate 20 on a plane.

[0195] The light-shielding pattern layer 312 is disposed on one surface of the base layer 311 and includes a pattern having light-shielding properties. The light-shielding pattern layer 312 is disposed on the back surface of the base layer 311 so as to face the pressure member 350. The thickness of the light-shielding pattern layer 312 is not particularly limited, but may be in the range of 80 nm to 180 nm. If the layer is too thin, it is difficult to obtain the desired light-shielding properties, and if the layer is too thick, it is difficult to process the light-shielding pattern with high precision.

[0196] The light-shielding pattern layer 312 is not particularly limited as long as it is a material having light-shielding properties, and examples thereof include chromium (Cr), chromium oxynitride (CrON), chromium nitride (CrN), molybdenum silicide oxide (MoSiO), molybdenum silicide oxynitride (MoSiON), tantalum oxide (TaO), tantalum silicide oxide (TaSiO), etc. In one embodiment, chromium (Cr) is selected for the light-shielding pattern layer 312.

[0197] The light-shielding pattern layer 312 includes a plurality of openings 312-OS. A laser beam can pass through the plurality of openings 312-OS. Therefore, the plurality of openings 312-OS can define a transmission region of the laser beam. Here, light irradiated from the laser irradiation unit 500 passes through the plurality of openings 312-OS of the light-shielding pattern layer 312 and is applied to a plurality of light-emitting elements LE arranged on the display substrate 20.

[0198] If the light-shielding pattern layer 312 is farther from the light-emitting element LE, diffraction of light occurs at the boundary of the opening, and an error may occur between the opening and the transmission area of ​​the laser beam.

[0199] The protective layer 313 is disposed on one side of the base layer 311 on which the light-shielding pattern layer 312 is formed, and protects the surface of the light-shielding pattern layer 312 to prevent damage to the light-shielding pattern. The thickness of the protective layer 313 is not particularly limited, but may be in the range of about 2 to 3 μm. The protective layer 313 may be made of a transparent material, such as a transparent or translucent material, for example, a transparent resin.

[0200] The first mounting member 315 is attached to one surface of the outer periphery of the mask member 310. For example, the first mounting member 315 may be attached to the front surface of the outer periphery of the protective layer 313. The first mounting member 315 may be, for example, any one of an electrostatic chuck, an adhesive chuck, a vacuum chuck, and a porous vacuum chuck. The first mounting member 315 may also be, but is not limited to, a clamp. The first mounting member 315 does not overlap with the path of the laser light.

[0201] 17, the gas pressure regulator 353 opens the gas valve to fill the sealed space 350-S between the first and second transparent plates 351 and 352 with gas through the gas conduit 354. As the gas fills the sealed space 350-S, the pressure inside the sealed space 350-S increases and the gas expands downward, i.e., toward the display substrate 20, generating a downward pressure.

[0202] The second light-transmitting plate 352 expands downward by filling it with gas, and a uniform pressure is applied to the surface of the light-emitting element LE arranged on one surface of the donor substrate TSUB.

[0203] The laser irradiation unit 500 irradiates laser light in a direction toward the lower first light-transmitting plate 351. Here, the light irradiated from the laser irradiation unit 500 passes through the openings 312-OS defined by the light-shielding pattern layer 312, the first light-transmitting plate 351, the second light-transmitting plate 352, and the openings 380-OS of the support member 380, and is applied to the plurality of light-emitting elements LE of the donor substrate TSUB. In other words, only the laser light that passes through the openings 312-O corresponding to the donor substrate TSUB can be applied to the plurality of light-emitting elements LE.

[0204] FIG. 18 is a side cross-sectional view schematically showing a display panel manufacturing apparatus according to another embodiment, and FIG. 19 is a side cross-sectional view showing a micro LED transfer method using the display panel manufacturing apparatus of FIG.

[0205] 18 and 19, the display panel manufacturing apparatus differs from that described with reference to Figures 7 to 15 in that the pressing unit 300 includes a metal mask 1310 instead of the light-blocking pattern layer 312. Descriptions that overlap with the embodiment of Figures 7 to 15 will be omitted.

[0206] 18 and 19, the pressure applying section 300 may include a metal mask 1310, a first mounting member 1315, a pressure applying member 350, a support member 380, and a second mounting member 385.

[0207] The metal mask 1310 may be an open mask including a light-blocking pattern, for example, the metal mask 1310 may be disposed between the pressure member 350 and the support member 380.

[0208] The metal mask 1310 is not particularly limited as long as it is a material that reflects laser light, and examples thereof include metal materials such as aluminum, etc. For example, the metal mask 1310 may be a fine metal mask including a light-shielding pattern.

[0209] The metal mask 1310 may include openings 1310-OS that overlap the openings 380-OS of the support member 380.

[0210] The metal mask 1310 has a slope on the side of the opening 1310-OS. The metal mask 1310 may have different vertical and horizontal dimensions at the top and bottom of the opening 1310-OS. For example, the opening width of the metal mask 1310 becomes wider at the top.

[0211] The pressure member 350 is disposed on the front side of the metal mask 1310 and can be moved in a direction toward the display substrate 20 so as to approach the display substrate 20 .

[0212] The metal mask 1310 may have an area larger than the range of the laser irradiated from the laser irradiation unit 500. The metal mask 1310 includes a plurality of openings. The laser beam can pass through the openings. Therefore, the openings can define a transmission area of ​​the laser beam. Here, the light irradiated from the laser irradiation unit 500 passes through the transmission area defined by the metal mask 1310 and is applied to a plurality of light-emitting elements LE arranged on one surface of the donor substrate TSUB.

[0213] The mounting member 1315 is attached to one surface of the outer periphery of the metal mask 1310. For example, the mounting member 1315 may be disposed on the front surface of the outer periphery of the metal mask 1310. The mounting member 1315 may include, but is not limited to, any one of an electrostatic chuck, an adhesive chuck, a vacuum chuck, and a porous vacuum chuck. For example, the mounting member 1315 may be a clamp. The mounting member 1315 does not overlap with the path of the laser light.

[0214] The pressure member 350 is disposed on the front side of the metal mask 1310 and can be moved in a direction approaching the display substrate 20 .

[0215] The pressure member 350 may include a first light-transmitting plate 351 , a second light-transmitting plate 352 , a gas pressure regulator 353 , a gas conduit 354 and a holding frame 355 .

[0216] The gas pressure regulator 353 opens the gas valve to fill the sealed space 350 -S between the first light-transmitting plate 351 and the second light-transmitting plate 352 with gas through the gas conduit 354 .

[0217] As the sealed space 350-S is filled with gas, the pressure inside the sealed space 350-S increases, causing the second translucent plate 352 to expand downward, i.e., toward the display substrate 20, generating a downward pressure.

[0218] When filled with gas, the second light-transmitting plate 352 moves downward, generating a downward pressure force.

[0219] The second light-transmitting plate 352 may be formed of an elastic material such as a silicone resin multilayer, a silicone resin-PET (polyethylene terephthalate) laminate layer, or PDMS (polydimethylsiloxane). When the second light-transmitting plate 352 is formed of an elastic material, the second light-transmitting plate 352 can expand downward when filled with gas. This allows the second light-transmitting plate 352 to have an uneven shape along the openings 1310-OS of the metal mask 1310. For example, the area overlapping the openings of the metal mask 1310 may be recessed relatively downward, while the area overlapping the pattern between the openings may be bulged relatively upward.

[0220] 20 is a side cross-sectional view schematically showing a display panel manufacturing apparatus according to another embodiment, and FIG. 21 is a side cross-sectional view showing a micro LED transfer method using the display panel manufacturing apparatus of FIG.

[0221] 20 and 21, the display panel manufacturing apparatus differs from that described with reference to Figures 18 and 19 in that a metal mask 1310 is placed between the pressure member 350 and the laser irradiation unit 500. Descriptions that overlap with the embodiment of Figures 18 to 19 will be omitted.

[0222] The openings 1310-OS of the metal mask 1310 can be arranged so that the openings become narrower as they go upward.

[0223] The first angle θ1 formed by the first side surface S1 of the opening 1310-OS of the metal mask 1310 and the second angle θ2 formed by the second side surface S2 of the opening 1310-OS may be the same. In the metal mask 1310, the first angle θ1 formed between the top surface (reflective surface) of the peripheral portion and the grating portion and the first side surface S1 and the second angle θ2 formed between the top surface and the second side surface S2 are obtuse angles greater than 90 degrees and may be the same. For example, the opening of the metal mask 1310 may be an isosceles trapezoid in the laminate cross section.

[0224] In another embodiment, the first side S1 and the second side S2 of the opening 1310-OS of the metal mask 1310 form an obtuse angle of more than 90 degrees, but the inclined surface may have a curvature. The inclination may become gentler as it goes up, but is not limited to this.

[0225] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art will understand that the present invention can be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the above-described embodiments are illustrative in all respects and are not limiting.

[0226] According to a preferred specific embodiment, it is as follows.

[0227] The background and issues of this case are as follows (i) to (vi).

[0228] (i) Micro LED displays are being considered as one of the next-generation displays following liquid crystal displays and organic light-emitting displays (OLEDs). In a typical example, a micro LED display is configured by mounting LED chips (referred to as "light-emitting elements LE" in this application) measuring 2 to 50 μm in length and width on a backplane (TFT array substrate) on which pixel circuits for each sub-pixel are formed, and arranging them in a matrix. The following two internet documents are for reference only and cannot be considered prior art in this case. (ia) MicroLED https: / / en.wikipedia.org / wiki / MicroLED (ib) Future Technology "Micro LED Display": Particle-Aligned Anisotropic Conductive Film "ArrayFIX" Supporting Its Popularization (Published November 1, 2024) https: / / techtimes.dexerials.jp / bonding / micro-led-future-technology /

[0229] (ii) Micro LED displays are expected to have a long lifespan, do not suffer from burn-in or degradation like organic light-emitting diode (OLED) displays, and can also be made flexible or transparent.

[0230] (iii) In one typical example, an LED chip ("light-emitting element LE") can be attached to the backplane at the location of each pixel electrode by, for example, pressing an anisotropic conductive film (ACF) between them (see (ib) above).

[0231] (iv) When mounting using an anisotropic conductive film (ACF), according to the reference example (not prior art) in (ib) above, small pieces of the anisotropic conductive film (ACF) are attached to predetermined locations on a glass plate (corresponding to the "relay substrate" and "donor substrate TSUB" in the present application), and then the small pieces of the anisotropic conductive film (ACF) on the glass plate are transferred onto the backplane. During this transfer, laser light is irradiated to melt the small pieces of the anisotropic conductive film (ACF). After this, the LED chip is attached onto the backplane by thermocompression bonding. (The last part of the diagram in (ib) above)

[0232] (v) According to FIG. 1 and related explanations of Patent Document 1, when the micro LED chip (60) attached to the relay substrate (20) via the adhesive layer (21) is transferred to the target substrate (40; corresponding to the backplane), laser light is irradiated from the back side through the mask (30) to melt the bonding layer (41-1) on the target substrate (40).

[0233] (vi) Through careful investigation, the present inventors have found that the following may occur when transferring an LED chip from an interposer substrate (20; the donor substrate TSUB of the present application) to a backplane. (vi-1) Due to partial insufficient pressure, thermocompression bonding to anisotropic conductive film (ACF) and the like and the resulting electrical continuity are insufficient. (vi-2) In particular, the pressure plate that transmits the laser beam undergoes partial thermal deformation due to the heat generated by the irradiation of the laser beam, resulting in localized areas where the pressure is insufficient.

[0234] In some specific embodiments of the present application, the following A1 to A2 are particularly used, and further at least one of A3 to A9 is used.

[0235] A1 When transferring the LED chip (light-emitting element EL) from the relay substrate (donor substrate TSUB) to the backplane (substrate 20), air pressure is applied through an elastically deformable translucent plate (second translucent plate 352) that transmits laser light, and laser light is irradiated.

[0236] A2 To apply air pressure, an air chamber (sealed space 350-S) is formed between another light-transmitting plate (first light-transmitting plate 351) that transmits laser light and an elastically deformable light-transmitting plate (second light-transmitting plate 352), and controlled compressed air can be supplied to this air chamber.

[0237] A3 During transfer, a holding substrate (support substrate 380) for the relay substrates is used, which is provided with openings (openings 380-OS) into which a large number (two or more, particularly four or more) of relay substrates (donor substrates TSUB) are fitted and held. A3-1 The holding substrate (support substrate 380) for the relay substrate is particularly composed of a frame-shaped outer periphery and vertical and horizontal lattice portions.

[0238] A4 The thickness (height 20-h) of the holding substrate (support substrate 380) for the relay substrate is substantially equal to the sum of the thickness (height Th, including the adhesive layer ADL) of the relay substrate (donor substrate TSUB) and the thickness (height Lh) of the LED chip (light-emitting element EL).

[0239] A5 During the transfer, a photomask (mask member 310) is used so that the laser is irradiated only onto the regions of the openings (openings 380-OS) of the holding substrate (support substrate 380).

[0240] A5-1 In this case, the photomask (mask member 310) can be sandwiched between an elastic light-transmitting plate (second light-transmitting plate 352) for pressure application and a holding substrate (support substrate 380) in which the relay substrates (donor substrates TSUB) are fitted into the openings (openings 380-OS) (Figs. 7, 14-15, 18-19 of the present application). A5-2 Instead of a photomask, a metal mask (1310) such as that used for vapor deposition can also be used (see Figures 18-20 of the present application). A5-3 The photomask (mask member 310) or metal mask (1310) can also be placed on another light-transmitting plate (first light-transmitting plate 351). (Figs. 16-17 and 20 of the present application)

[0241] A6 The elastically deformable light-transmitting plate (second light-transmitting plate 352) and another light-transmitting plate (first light-transmitting plate 351) are held at their peripheries by a sealed frame-like member (holding frame 355).

[0242] A6-1 The internal air chamber (sealed space 350-S) can be connected to the external gas pressure regulator 353 through a "gas conduit 354" that passes horizontally through this frame-shaped member (holding frame 355). A6-2 The frame-shaped member (holding frame 355) may be provided with horizontal rail-like protrusions that are sandwiched between the peripheral edge of an elastically deformable light-transmitting plate (second light-transmitting plate 352) and the peripheral edge of another light-transmitting plate (first light-transmitting plate 351). A6-3 A buffer material 356 such as an O-ring may be provided between the rail-shaped protrusion and the periphery of the elastic light-transmitting plate (second light-transmitting plate 352).

[0243] A7 The elastically deformable light-transmitting plate (second light-transmitting plate 352) can be made of a transparent elastic material such as a silicone resin-based sheet or a laminate sheet of silicone resin and PET, etc. The elastic material can have a flexural modulus (ISO 178) of, for example, 0.1 or more or 1 or more.

[0244] A7-1 The other light-transmitting plate (first light-transmitting plate 351) can be made of glass or other transparent inorganic oxide materials. However, it can also be made of a rigid transparent resin material such as an acrylic resin. Here, "rigid" means that the flexural modulus (ISO 178) can be, for example, 500 or more, 2000 or more, or 5000 or more. A7-2 The elastically deformable light-transmitting plate (second light-transmitting plate 352) may also be made of a rigid transparent resin material such as acrylic resin, or may be made of a relatively thin tempered glass plate, depending on the circumstances.

[0245] A8 During transfer, the base (mounting stage 200) on which the backplane (substrate 20) is placed is positioned at least partially inside the frame-shaped support / mounting member (second mounting member 385) that mounts and fixes the outer periphery of the holding substrate (support substrate 380) for the relay substrate (Fig. 14 of the present application).

[0246] A8-1 When a photomask (mask member 310) or metal mask (1310) is sandwiched between an elastically deformable light-transmitting plate (second light-transmitting plate 352) and a holding substrate (support substrate 380) for a mask member relay substrate, the holding substrate (support substrate 380) for the relay substrate is positioned so that it is at least partially inserted inside a frame-shaped support / mounting member (first mounting member 315) that places and fixes the outer periphery of the photomask (mask member 310) (Fig. 14 of the present application).

[0247] A9 The "laser irradiation unit 500" that irradiates the laser light comprises a laser light source 510 and a diffuser / condenser plate (optical system 530) on which a large number of lenses are arranged. This diffuser / condenser plate (optical system 530) extends over an area that entirely covers the relay substrate (donor substrate TSUB), and focuses the laser light in the direction toward the relay substrate (donor substrate TSUB). [Explanation of symbols]

[0248] 10 Display device 20 Display board 200 Mounting stage 300 Pressure unit 310 Mask material 320 Plate transport member 350 Pressure member 500 Laser irradiation unit

Claims

1. a mounting stage on which a display substrate is mounted; a mask member disposed on a front side of the mounting stage, the mask member having a first opening defined therein corresponding to a transmission region of the laser beam; a pressure unit including a pressure member that applies pressure to a plurality of donor substrates disposed on the display substrate; a support member disposed on the display substrate, the support member having a plurality of second openings formed in areas corresponding to the donor substrates arranged on the display substrate; a pressure unit including a pressure member that applies pressure to the support member; a laser irradiation unit disposed above the mask member and configured to irradiate laser light onto the light emitting element of the donor substrate; The display panel manufacturing apparatus, wherein the support member has a height equal to the sum of the thickness of the donor substrate and the height of the light-emitting element.

2. The display panel manufacturing apparatus according to claim 1 , wherein the second opening overlaps the first opening and the donor substrate.

3. The display panel manufacturing apparatus according to claim 1 , wherein the support member protrudes outward beyond the display substrate.

4. 2. The display panel manufacturing apparatus according to claim 1, wherein the mask member includes a base layer that transmits laser light, and a light-shielding pattern layer that is disposed on the base layer and includes the openings.

5. The display panel manufacturing apparatus according to claim 4 , wherein the mask member is a photomask, and further includes a protection layer disposed on the light-shielding pattern layer.

6. the pressure member is disposed on the support member and includes a first light-transmitting plate and a second light-transmitting plate overlapping each other in a thickness direction; 2. The display panel manufacturing apparatus of claim 1, wherein a sealed space is formed between the first light-transmitting plate and the second light-transmitting plate, and the pressurizing member further includes a gas pressure regulator that adjusts the gas pressure in the sealed space, and a gas conduit connected between the gas pressure regulator and the sealed space.

7. The display panel manufacturing apparatus according to claim 6 , wherein the second light-transmitting plate moves downward when the gas pressure in the sealed space increases.

8. a holding frame for fixing both ends of the first light-transmitting plate and the second light-transmitting plate; The display panel manufacturing apparatus of claim 7 , further comprising a buffer material disposed between the second light-transmitting plate and the holding frame.

9. The display panel manufacturing apparatus according to claim 5 , wherein the base layer is disposed closer to the display substrate than the protective layer.

10. The display panel manufacturing apparatus according to claim 5 , wherein the base layer is disposed closer to the laser irradiation unit than the protective layer.

11. a first attachment member attached to one surface of the outer periphery of the mask member and supporting the mask; 2. The display panel manufacturing apparatus of claim 1, further comprising a second mounting member attached to one surface of the outer periphery of the support member to support the mask.

12. The display panel manufacturing apparatus according to claim 1 , wherein the mask member is disposed between the support member and the pressure member.

13. The display panel manufacturing apparatus according to claim 1 , wherein the mask member is disposed between the pressure member and the laser irradiation unit.

14. 2. The display panel manufacturing apparatus according to claim 1, wherein the mask member is a metal mask having reflectivity and in which the first opening is defined.

15. 15. The display panel manufacturing apparatus of claim 14, wherein the first opening includes a first side and a second side opposite to the first side, and a first angle formed between the first side and the top surface of the metal mask and an angle formed between the top surface of the metal mask and the second side are the same as each other, and the first side and the second side have a curvature.

16. The display panel manufacturing apparatus of claim 1 , wherein the first and second light-transmitting plates are made of a rigid material.

17. the first light-transmitting plate is made of a rigid material; The display panel manufacturing apparatus of claim 5 , wherein the second light-transmitting plate is made of an elastic material.

18. placing a display substrate on a mounting stage; disposing a plurality of donor substrates and a support member on the display substrate, and disposing one donor substrate in each of a plurality of second openings defined in the support member; placing a mask member and a pressure member over the donor substrate; pressing the donor substrate with the pressing member, and irradiating a laser beam onto a light emitting element of the donor substrate through a first opening defined in the mask member; The method for manufacturing a display panel, wherein the support member has a height equal to the sum of the thickness of the donor substrate and the height of the light-emitting element.

19. the pressure member is disposed on the support member and includes a first light-transmitting plate and a second light-transmitting plate overlapping each other in a thickness direction; 20. The method for manufacturing a display panel according to claim 18, wherein a sealed space is formed between the first light-transmitting plate and the second light-transmitting plate, and the pressure member adjusts a gas pressure in the sealed space, thereby causing the second light-transmitting plate to move downward and pressurize the donor substrate.

20. The step of irradiating the light emitting element of the donor substrate with laser light includes:

19. The method for manufacturing a display panel according to claim 18, wherein the laser irradiation unit is disposed above the mask member, and when laser light is irradiated onto the mask member, the laser light that passes through a first opening of the mask member passes through a second opening of the support member and is irradiated onto the light-emitting element of the donor substrate, and the laser light that is irradiated onto an area other than the first opening of the mask member is blocked.

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