Exposure Apparatus and Manufacturing Method of Display Device using the same

Abstract

An exposure apparatus and a method for manufacturing a display device using the same are provided. The exposure apparatus includes a light source unit that provides light for exposure and includes a plurality of micro LEDs arranged in a matrix form; a substrate transfer unit that transfers a target substrate; and a control unit that controls at least one of the light source unit and the substrate transfer unit, wherein the control unit assigns a coordinate or address to each micro LED and individually controls the amount of light of each micro LED according to a preset pattern based on the coordinate or address.

Description

Technology Field

[0001] The present invention relates to an exposure apparatus and a method for manufacturing a display device using the same. Background Technology

[0002] A photolithography device is a device that manufactures complex circuit patterns using light, similar to photographic printing technology. Photolithography devices can be used to form patterns for the fabrication of, for example, semiconductor devices, display panels such as LCDs (Liquid Crystal Displays), PDPs (Plasma Display Panels), and ELDs (Electroluminescent Displays), integrated circuits (ICs), and flat panel displays.

[0003] Conventional photolithography forms a desired pattern on a substrate coated with photoresist (PR) by exposing light through a photomask in which a pattern is formed with a metal thin film (mainly chrome) on a quartz or glass plate.

[0004] In the above process, instead of a photomask, a patterning device composed of an array of individually operable elements can be used. The patterning device is programmed to form a beam of a desired pattern using an array of individually operable elements. Since this "maskless" system can modify the emitted beam into a desired pattern through programming, it can create patterns of various shapes without additional cost and has the advantages of being faster and cheaper compared to existing mask-based systems.

[0005] A representative programmable patterning device is an exposure system utilizing a digital mirror device (DMD). A DMD is a device used to generate images in electronic products such as projectors and TVs, and it is a core component for creating patterns in maskless lithography systems. In a DMD, a mirror rotates according to an electrical signal to form an image of a desired pattern. In other words, a DMD is similar to a photomask capable of pattern deformation. Exposure systems using DMDs have the advantage of shortening design time by facilitating the use of previous data during design changes and enabling immediate correction of design errors. On the other hand, DMDs have the disadvantage of requiring a complex optical system for projecting the patterning image, and light loss occurs because light is irradiated through the DMD. The problem to be solved

[0006] The problem that the present invention aims to solve is to provide an exposure apparatus capable of forming various patterns without replacing a light source or mask, and a method for manufacturing a display device using the same.

[0007] Another problem that the present invention aims to solve is to provide an exposure device with low light loss and a method for manufacturing a display device using the same.

[0008] Another problem that the present invention aims to solve is to provide an exposure device that can save installation space and a method for manufacturing a display device using the same.

[0009] The problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0010] An exposure device according to one embodiment for solving the above problem comprises: a light source unit that provides light for exposure and includes a plurality of micro LEDs arranged in a matrix form; a substrate transfer unit that transfers a target substrate; and a control unit that controls at least one of the light source unit and the substrate transfer unit, wherein the control unit assigns a coordinate or address to each micro LED and individually controls the amount of light of each micro LED according to a preset pattern based on the coordinate or address.

[0011] The size of each of the above micro LEDs may be 100 μm or less.

[0012] The average pitch between each of the above micro LEDs may be 5000 μm or less.

[0013] The emission wavelength of each of the above micro LEDs may be 200 nm to 500 nm.

[0014] Each of the above micro LEDs may include a first semiconductor layer disposed on the light source substrate; an active layer disposed on the first semiconductor layer; a second semiconductor layer disposed on the active layer; and a reflector disposed to surround the first semiconductor layer, the active layer, and the second semiconductor layer, with the lower side open.

[0015] The above reflector has a shape that is narrow at the top and wide at the bottom, and the inclination of the side of the reflector may be 40 to 90 degrees.

[0016] The light source unit may include a light source unit substrate that supports the plurality of micro LEDs; and an optical system disposed below the light source unit substrate.

[0017] The light source may further include a light-blocking member disposed along the boundary between the plurality of micro LEDs on one side of the light source substrate.

[0018] The above optical system may include a plurality of micro-lenses.

[0019] During exposure, the distance between the light source unit and the target substrate loaded on the substrate transfer unit may be about 500 μm or less.

[0020] The above control unit can individually control the on or off of each micro LED.

[0021] The above control unit can individually control the driving time of each micro LED.

[0022] The control unit above controls the light source unit to output a first preset pattern during a first preset time, and when it is determined that the first preset time has elapsed, it can control the light source unit to output a second preset pattern different from the first preset pattern.

[0023] A method for manufacturing a display device according to one embodiment for solving the above problem comprises the steps of: stacking at least one material layer on a base substrate; applying a photosensitive material on the at least one material layer; individually controlling the light intensity of each micro LED to output a preset pattern; exposing the photosensitive material; removing a portion of the photosensitive material; and etching a first pattern on the at least one material layer.

[0024] The step of individually controlling the light intensity of each micro LED may include the step of individually controlling the on or off of each micro LED.

[0025] The step of individually controlling the light intensity of each micro LED may include the step of individually controlling the driving time of each micro LED.

[0026] The step of individually controlling the light intensity of each of the above micro LEDs may include the step of outputting a first preset pattern for a first preset time and outputting a second preset pattern for a second preset time.

[0027] The above method for manufacturing a display device may further include a step of removing a portion of the remaining photosensitive material.

[0028] The method may further include a step of etching a second pattern on at least one material layer.

[0029] Specific details of other embodiments are included in the detailed description and drawings. Effects of the invention

[0030] An exposure device according to various embodiments and a method for manufacturing a display device using the same can reduce process costs and increase process efficiency.

[0031] An exposure device according to various embodiments and a method for manufacturing a display device using the same can minimize light loss.

[0032] An exposure device according to various embodiments and a method for manufacturing a display device using the same can save installation space.

[0033] The effects according to the embodiments are not limited to those exemplified above, and a wider variety of effects are included in this specification. Brief explanation of the drawing

[0034] FIG. 1 is a perspective view of an exposure device according to one embodiment. Figure 2 is a top view of the maskless lithography of Figure 1. Figure 3 is a plan view of the light source part of Figure 1 seen from below. Figure 4 is a cross-sectional view taken along A-A' of Figure 3. Figure 5 is a diagram illustrating an auxiliary optical system. FIGS. 6 to 11 are drawings illustrating a method for controlling an exposure device according to an embodiment of the present invention. FIGS. 12 to 14 are drawings illustrating a method for controlling an exposure device according to another embodiment of the present invention. FIGS. 15 to 20 are drawings illustrating a method for manufacturing a display device according to an embodiment of the present invention. FIGS. 21 to 24 are drawings illustrating an exposure apparatus according to another embodiment of the present invention and a method for manufacturing a display device using the same. Specific details for implementing the invention

[0035] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0036] When elements or layers are referred to as being "on" another element or layer, this includes cases where another layer or element is interposed directly on or in the middle of another element. Throughout the specification, the same reference numerals refer to the same components. Shapes, sizes, ratios, angles, numbers, etc., disclosed in the drawings for describing embodiments are examples, and therefore the invention is not limited to the depicted details.

[0037] Specific embodiments will be described below with reference to the attached drawings.

[0038] FIG. 1 is a perspective view of an exposure apparatus according to one embodiment. FIG. 2 is a top view of the maskless lithography of FIG. 1. FIG. 3 is a bottom view of the light source of FIG. 1. FIG. 4 is a cross-sectional view taken along A-A' of FIG. 3.

[0039] In the embodiments, the first direction (X), the second direction (Y), and the third direction (Z) intersect each other in different directions. In the drawings, the horizontal direction of the exposure device (1) is defined as the first direction (X), the vertical direction as the second direction (Y), and the height direction as the third direction (Z). The third direction includes an upper direction facing upward on the drawings and a lower direction facing downward on the drawings. Accordingly, one side of a member positioned to face the upper direction may be referred to as the upper surface, and the other side of a member positioned to face the lower direction may be referred to as the lower surface. However, the directions mentioned in the embodiments should be understood as referring to relative directions, and the embodiments are not limited to the mentioned directions.

[0040] In the following, examples of maskless photolithography devices are provided, for instance, in which a photolithography process generally using photoresist is not required. However, the examples are not limited thereto, and the exposure devices include all devices used for exposure and development processes for pattern formation.

[0041] Referring to FIGS. 1 to 4, the exposure device (1) includes a light source unit (100), a substrate transfer unit (200a), and a control unit (300). The exposure device (1) may further include a sensing unit (400).

[0042] The light source unit (100) includes a plurality of light-emitting elements and is positioned above the substrate transfer unit (200a). The light source unit (100) can project light downward toward a target substrate (10) loaded on the substrate transfer unit (200a).

[0043] The light source unit (100) can expose a target substrate (10) to light so that a layer containing a photoresist or a photosensitive material is cured according to a specific pattern. The target substrate (10) refers to a substrate that is exposed by an exposure device (1). In one embodiment, the target substrate (10) may include a base substrate (11), a material layer (12) stacked on the base substrate (11), and a photosensitive material (PR) stacked on the material layer, but is not limited thereto. The photosensitive material (PR) may be a photosensitive film formed by applying a photoresist onto the material layer. The material layer may be, for example, a material for forming a thin-film transistor.

[0044] The light source unit (100) may be positioned to overlap with the substrate transfer unit (200a). Specifically, the substrate transfer unit (200a) is positioned along a first direction (X) in which the target substrate (10) is transferred, and the light source unit (100) is positioned along a second direction (Y) that intersects the first direction (X), and at least a portion of the substrate transfer unit (200a) and the light source unit (100) may overlap in a third direction (Z). In one embodiment, the width of the light source unit (100) in the second direction (Y) may be greater than or equal to the width of the substrate transfer unit (200a) in the second direction (Y). Accordingly, the exposure device (1) can form a pattern in a specific area of ​​the target substrate (10) positioned between the light source unit (100) and the substrate transfer unit (200a) in a single exposure.

[0045] The light source unit (100) may be positioned at a predetermined distance from the substrate transfer unit (200a). The predetermined distance may vary depending on the thickness of the target substrate (10). Specifically, the exposure device (1) may be positioned in close proximity to the substrate transfer unit (200a) or the target substrate (10) as the optical system (140), described later, is integrally provided with the light source unit (100). Accordingly, the size of the device or system for lithography can be miniaturized, and light loss can be minimized. For example, during exposure, the distance in the third direction (Z) between the light source unit (100) and the substrate transfer unit (200a) may be about 500 μm or less. As another example, during exposure, the distance in the third direction (Z) between the light source unit (100) and the target substrate (10) may be about 500 μm or less. As another example, the distance in the third direction (Z) between the light source unit (100) and the target substrate (10) during exposure may be about 5 μm or less. As another example, the distance in the third direction (Z) between the light source unit (100) and the target substrate (10) during exposure may be about 1 μm or more. Accordingly, interference caused by the difference in flatness between the light source unit (100) and the target substrate (10), and the transfer of material, such as photoresist, due to contact between the two, can be prevented. In addition, if the light source unit (100) and the target substrate (10) are in excessive contact, a dark area may be formed on a part of the target substrate (10) by the light-blocking member (130) described later, but the formation of the dark area can be prevented by separating the light source unit (100) and the target substrate (10) by a predetermined distance to properly disperse the light. In some embodiments, the exposure device (1) may further include a light source moving unit that is controlled by a control unit (300) described below and capable of moving the light source unit (100) in at least one of a first direction (X) to a third direction (Z) for alignment of the light source unit (100).

[0046] The light source unit (100) may be positioned parallel to the target substrate (10). In other words, the light source unit (100) may be positioned parallel to the transport direction of the substrate transport unit (200a) or the upper surface of the substrate transport unit (200a). Accordingly, the light source unit (100) can uniformly illuminate the target substrate (10). In one embodiment, the substrate is transported in a first direction (X), and the light source unit (100) may be positioned along a plane parallel to the first direction (X) and the second direction (Y). In some embodiments, the light source unit (100) may be positioned to be inclined with the target substrate (10) or the direction of movement of the target substrate (10). In some embodiments, the light of the light source unit (100) may be individually controlled according to the inclination by the control unit (300) described later.

[0047] The light source unit (100) may include a plurality of unit light-emitting cells (LC). Each of the unit light-emitting cells (LC) may correspond to each micro LED (120) of the micro LED array (MLA) described later. The light source unit (100) is electrically connected to a control unit (300) described later, and each unit light-emitting cell (LC) may be controlled to be individually turned on or turned off by the control unit (300). In some embodiments, the light source unit (100) further includes a driver integrated circuit that applies a driving signal to the micro LED (120) corresponding to each unit light-emitting cell (LC), and the driver integrated circuit may drive each micro LED (120) individually based on a control signal received from the control unit (300).

[0048] The light source unit (100) may include a light source unit substrate (110), a micro LED array (MLA), and an optical system (140). The light source unit (100) may further include a light-blocking member (130).

[0049] The light source substrate (110) is positioned parallel to the target substrate (10) on the substrate transfer unit (200a) and supports the lower part of the micro LED array (MLA). In one embodiment, the thickness of the light source substrate (110) may be about 100 μm to 200 μm.

[0050] The light source substrate (110) is made of a transparent material so that light emitted from the micro LED (120) passes through the light source substrate (110). It is possible to reach the target substrate (10). The light source substrate (110) may be made of a transparent insulating material such as, for example, sapphire, glass, or polymer resin, but is not limited thereto. In some embodiments, the light source substrate (110) comprises a plurality of layers made of a transparent conductive material, and the plurality of layers may include circuits such as, for example, thin-film transistor structures for individual control of each micro LED (120).

[0051] A micro LED array (MLA) is disposed on the upper side of a light source substrate (110). The micro LED array (MLA) may include a plurality of micro LEDs (120). Here, a micro LED (120) refers to a light-emitting element having a very small size. In one embodiment, the size of each micro LED (120) may be 100 μm or less. In some embodiments, the size of each micro LED (120) may be 20 μm to 40 μm.

[0052] A plurality of micro LEDs (120) may be arranged in rows and columns along a first direction (X) and a second direction (Y) that intersects the first direction (X). In one embodiment, the first direction (X) and the second direction (Y) may intersect perpendicularly, but are not limited thereto. As the micro LEDs (120) have a very small size, a plurality of micro LEDs (120) may be arranged in at least hundreds or thousands of units along the first direction (X) and the second direction (Y). In one embodiment, a plurality of micro LEDs (120) may be arranged such that the average pitch between each micro LED (120) is 5000 μm or less. In some embodiments, the average pitch between each micro LED (120) may be 20 μm to 40 μm.

[0053] A plurality of micro LEDs (120) project light downward toward a substrate transfer unit (200a) or a substrate. Each micro LED (120) can emit light having a wavelength in a specific range. Specifically, the emission wavelength of the micro LED (120) may include the ultraviolet region. For example, the emission wavelength of the micro LED (120) may be 200 nm to 500 nm. The light emitted from the micro LED (120) may pass through the light source substrate (110) and the optical system (140) to reach the substrate. Each micro LED (120) may have a structure of upper narrower and lower light for efficient light extraction. For example, the micro LED (120) may have various shapes such as a cone, a triangular pyramid, a square pyramid, a hexahedron, a rectangular prism, or a cylinder.

[0054] Each micro LED (120) may include a first semiconductor layer (121), a second semiconductor layer (122), an active layer (123), a first electrode (125), a second electrode (126), a reflector (124), and a control circuit (127).

[0055] The first semiconductor layer (121) may be disposed on the upper side of the light source substrate (110). As shown in FIG. 4, the first semiconductor layer (121) of each micro LED (120) may be disposed to be connected to the first semiconductor layer (121) of an adjacent micro LED (120), but is not limited thereto. The first semiconductor layer (121) may be an n-type semiconductor layer.

[0056] The second semiconductor layer (122) is disposed on the upper side of the active layer (123) described later. The second semiconductor layer (122) may be a p-type semiconductor layer.

[0057] In FIG. 4, the first semiconductor layer (121) and the second semiconductor layer (122) are each composed of a single layer, but the first semiconductor layer (121) and the second semiconductor layer (122) may each include a plurality of layers.

[0058] The active layer (123) is disposed between the first semiconductor layer (121) and the second semiconductor layer (122). For example, the active layer (123) may have a structure in which semiconductor materials with a large bandgap energy and semiconductor materials with a small bandgap energy are stacked together.

[0059] The first electrode (125) electrically connects the first semiconductor layer (121) and the first control unit circuit (127_1) described later.

[0060] The second electrode (126) electrically connects the second semiconductor layer (122) and the second control unit circuit (127_2) described later.

[0061] The reflector (124) is open at the bottom and is positioned to surround the first semiconductor layer (121), the active layer (123), and the second semiconductor layer (122) from the outside. The reflector (124) reflects light generated in the active layer (123) downward.

[0062] The reflector (124) has a shape that is narrower at the top and lower at the bottom so that the reflected light is aligned in a certain direction. In one embodiment, the side slope of the reflector (124) may be about 40° to 90°. In some embodiments, the side slope of the reflector (124) may be about 50°.

[0063] The reflector (124) may include a metal with high reflectivity or an alloy thereof. For example, the reflector (124) may include aluminum (Al), gold (Au), silver (Ag), nickel (Ni), copper (Cu), rhodium (Rh), palladium (Pd), zinc (Zn), ruthenium (Ru), lanthanum (La), titanium (Ti), platinum (Pt), or an alloy thereof.

[0064] A light-blocking member (130) is positioned on the lower side of the light source substrate (110). The light-blocking member (130) may be arranged in a grid shape to form a plurality of openings corresponding to each micro LED (120). The light-blocking member (130) may be positioned along the boundary of the unit light-emitting cell (LC) between each micro LED (120). The light-blocking member (130) may be made of a material that blocks the transmission of light by absorbing or reflecting light of at least a specific wavelength band. The light-blocking member (130) prevents the mixing of light emitted from different micro LEDs (120) and reduces external light reflection. In one embodiment, the light-blocking member (130) may be a black matrix made of, for example, a chrome-based metal material, a carbon-based organic material, or a resin.

[0065] The control unit circuit (127) electrically connects the light source unit (100) and the control unit (300) and transmits a control signal from the control unit (300) to each micro LED (120) to drive each micro LED (120) individually. The control unit circuit (127) may include components and / or wiring for driving each micro LED (120) individually, such as data lines, scan lines, transistors, and driving integrated circuits. In one embodiment, the control unit circuit (127) may include a first control unit circuit (127_1) that electrically connects the first electrodes (125) to the control unit (300) and a second control unit circuit (127_2) that electrically connects the second electrodes (126) to the control unit (300). In FIG. 4, the first control unit circuit (127_1) and the second control unit circuit (127_2) are shown side by side, but the arrangement and shape of the control unit circuit (127) are not limited thereto. In some embodiments, the first control unit circuit (127_1) may apply a first power supply voltage to each micro LED (120), and the second control unit circuit (127_2) may apply a second power supply voltage. Here, the second control unit circuit (127_2) may include, for example, a thin-film transistor, and the second power supply voltage may be applied individually to each micro LED (120), thereby allowing the control unit (300) to drive each micro LED (120) individually.

[0066] The optical system (140) is positioned on the lower side of the optical substrate. The optical system (140) can guide light from the micro LED (120) in a specific direction to align the direction of the light uniformly. In some embodiments, the optical system (140) may magnify or reduce the light from the micro LED (120).

[0067] By integrating the optical system (140) so as to be adjacent to the lower micro LED array (MLA) of the optical substrate, the light source unit (100) can be arranged in a simple form such as a bar on the substrate transfer unit (200a) as shown in FIG. 3. That is, the exposure device (1) can miniaturize the device or system for photolithography by using a fine-sized light-emitting element in which the optical system (140) is integrally provided, without requiring a separate optical system (140) and a device for aligning / uniformizing light.

[0068] The optical system (140) may be composed of materials such as glass, oxide, nitride, or sapphire, for example.

[0069] The optical system (140) may include a plurality of lenses. For example, the optical system (140) may include a micro-lens array in which lens structures with a size of 10 μm to 1000 μm are arranged two-dimensionally.

[0070] A microlens array may include a plurality of microlenses having positive or negative curvature. In one embodiment, the width of the microlens may be less than or equal to the width of the micro LED (120).

[0071] In one embodiment, each microlens of the microlens array may be placed for each micro LED (120). In some embodiments, each microlens of the microlens array may be placed for a plurality of micro LEDs (120).

[0072] The substrate transfer unit (200a) transfers the loaded target substrate (10) to a suitable position for exposure. The substrate transfer unit (200a) may include a substrate stage (210) and a substrate stage driving unit (220).

[0073] The substrate stage (210) supports the lower surface of the target substrate (10). The substrate stage (210) transports the target substrate (10) in at least one of a first direction (X) to a third direction (Z). In one embodiment, the substrate stage (210) transports the target substrate (10) in the first direction (X) such that at least a portion of the target substrate (10) placed on the upper side overlaps with the light source unit (100) in the third direction (Z).

[0074] The substrate stage driving unit (220) moves the substrate stage (210) so that the target substrate (10) is transported. The substrate stage driving unit (220) may be electrically connected to the control unit (300) described later. In one embodiment, the substrate stage driving unit (220) includes a cylindrical roller connected to the substrate stage (210), and by rotating or stopping the roller, at least a portion of the target substrate (10) requiring patterning located on the transport belt may be aligned below the light source unit (100).

[0075] The sensing unit (400) senses whether the light source unit (100) and the target substrate (10) are aligned so that the target substrate (10) can be aligned in the correct position. In one embodiment, the sensing unit (400) is positioned below the light source substrate to sense an alignment mark on the target substrate (10).

[0076] The control unit (300) controls at least one of the light source unit (100), the substrate transfer unit (200a), the transfer unit, and the sensing unit (400).

[0077] The control unit (300) can individually control each micro LED (120) of the micro LED array (MLA) to output a preset pattern. The preset pattern may be a pattern of light generated as the amount, intensity, or brightness of light from each micro LED (120) is individually controlled. Specifically, the control unit (300) may assign coordinates or addresses to each micro LED (120) and apply control signals individually to each micro LED (120) based on the coordinates or addresses. In one embodiment, the control unit (300) may set an X-axis address and a Y-axis address to each micro LED (120) and apply control signals corresponding to the X-axis address and Y-axis address set according to the shape of the preset pattern, thereby individually controlling each micro LED (120). Accordingly, the exposure device (1) does not require a separate mask for the exposure process and can easily implement various exposure patterns according to the shape of the photoresist pattern to be formed on the target substrate (10).

[0078] Figure 5 is a diagram illustrating an auxiliary optical system.

[0079] Referring to FIG. 5, the exposure device (1) may further include an auxiliary optical system (150).

[0080] An auxiliary optical system (150) is positioned between the light source unit (100) and the substrate transfer unit (200a) and may include at least one lens having a positive curvature or a negative curvature. In one embodiment, the auxiliary optical system (150) may magnify or reduce the light emitted from the light source unit (100). Accordingly, the exposure device (1) may form a more precise pattern, for example, of 1 μm or less, on the target substrate (10), and may concentrate or disperse light to a specific area of ​​the target substrate (10) according to the light intensity required for curing. In some embodiments, the auxiliary optical system (150) may align the light emitted from the light source unit (100) in a certain direction.

[0081] In FIG. 5, one auxiliary optical system (150) is illustrated, but multiple auxiliary optical systems (150) may be arranged.

[0082] The operation of the control unit (300) is described in detail below in FIGS. 6 to 14.

[0083] FIGS. 6 to 11 are drawings illustrating a method for controlling an exposure device according to an embodiment of the present invention.

[0084] FIG. 6 is a flowchart of a method for controlling an exposure device according to an embodiment of the present invention. FIG. 7 and FIG. 8 are side views illustrating the process of transferring and aligning a target substrate (10). FIG. 9 is a drawing illustrating a preset pattern. FIG. 10 is a drawing illustrating the step of outputting a preset pattern. FIG. 11 is a drawing illustrating a developed photoresist.

[0085] Referring to FIGS. 6 to 11, the exposure device control method may include the steps of loading a target substrate (10) onto a substrate transfer unit (200a) (S101), transferring the target substrate (10) (S102), outputting a preset pattern (S104), and transferring the target substrate (10) again (S105). The exposure device control method may be performed by the control unit (300) of the exposure device (1) of FIG. 1.

[0086] The method for controlling the exposure device is described in detail below in FIGS. 7 to 11.

[0087] Referring to FIG. 7, the control unit (300) controls the driving unit of the substrate transfer unit (200a) to transfer the target substrate (10) loaded on the substrate transfer unit (200a) in a first direction (X).

[0088] After transferring the target substrate (10), the exposure device control method may further include a step (S103) of determining whether the target substrate (10) and the light source unit (100) are aligned.

[0089] When the target substrate (10) is located below the light source unit (100), the control unit (300) receives information regarding alignment status from the sensing unit (400) and determines whether the target substrate (10) is aligned. If the target substrate (10) is not aligned, the control unit (300) controls the substrate transfer unit (200a) to ensure that the target substrate (10) is aligned to the correct position. If the target substrate (10) is aligned, the control unit (300) controls the light source unit (100) to output a preset pattern.

[0090] Referring to FIGS. 9 and 10, the preset pattern may be formed by individually turning on or off at least one unit light-emitting cell (LC) or micro LED (120) corresponding to a specific address or coordinate. For example, the preset pattern may be a pattern in which the micro LEDs (120) corresponding to (X2, Y2), (X2, Y3), (X3, Y2), (X4, Y2), (X4, Y3), and (X4, Y4) are turned off, and the micro LEDs (120) corresponding to the remaining coordinates are turned on. The preset pattern may include a plurality of patterns that are repeatedly arranged. The preset pattern of FIG. 8 is an example, and the preset pattern includes all various patterns that can be used in a lithography process or an exposure and development process.

[0091] The control unit (300) can control the light source unit (100) to adjust the intensity or brightness of a preset pattern. Specifically, the control unit (300) can control the light source unit (100) so that each micro LED (120) emits light of the same intensity or emits light of different intensities. The intensity includes brightness. In other words, the step of outputting a preset pattern may include controlling the first micro LED (120) to emit light at a first intensity and controlling the second micro LED (120) to emit light at a second intensity. Here, the first intensity and the second intensity may be the same or different. In the embodiment of FIGS. 9 and FIGS. 10, the micro LED (120) is exemplified as emitting light at the same intensity or brightness, but as in the embodiment of FIGS. 12 to 14 below, the output of each micro LED (120) may be controlled individually.

[0092] Referring to FIG. 10, as each micro LED (120) is individually turned on or off, some parts of the photoresist may be exposed and some parts may not be exposed. Specifically, the photoresist may be divided into an exposed area (EA) where the upper micro LED (120) is turned on and exposed to light, and a non-exposed area (NEA) where the upper micro LED (120) is turned off and not exposed to light.

[0093] Referring to FIG. 10, when the photoresist is a positive photoresist, a portion of the photoresist placed in the exposure area (EA) is selectively removed by a developer, and a portion of the photoresist placed in the non-exposure area (NEA) remains, so that, for example, a photoresist pattern such as FIG. 10 can be formed. Subsequently, the photoresist pattern can be used as a mask to etch a target material placed on a substrate into a desired shape. FIG. 10 illustrates a pattern formed using a positive photoresist, but is not limited thereto. In some embodiments, the photoresist may be a negative photoresist.

[0094] Referring again to FIGS. 7 and FIGS. 8, after outputting a preset pattern, the exposure device control method may further include a step of determining the exposure time.

[0095] The control unit (300) can determine whether the exposure time exceeds a preset time. The exposure time refers to the time during which the target substrate (10) is exposed to a preset pattern output from the light source unit (100).

[0096] If the exposure time is less than or equal to the preset time, the control unit (300) controls the light source unit (100) to continuously output the preset pattern.

[0097] If the exposure time exceeds a preset time, the control unit (300) controls the substrate transfer unit (200a) to transfer the target substrate (10) in a first direction (X). Here, the control unit (300) can control the light source unit (100) so that it no longer outputs a preset pattern. In some embodiments, the exposure device (1) further includes an additional substrate transfer unit (200a) capable of transferring the target substrate (10) in a second direction (Y) or a third direction (Z), and the control unit (300) can control the substrate transfer unit (200a) to transfer the target substrate (10) in a direction different from the previously transferred direction.

[0098] After the target substrate (10) has moved a sufficient distance, the control unit (300) can determine whether another area of ​​the target substrate (10) is aligned with the light source unit (100).

[0099] When another area of ​​the target substrate (10) is aligned with the light source unit (100), the control unit (300) can control the light source unit (100) to continue outputting the same pattern to another area of ​​the target substrate (10) or to output a different pattern.

[0100] FIGS. 12 to 14 are drawings illustrating a method for controlling an exposure device according to another embodiment of the present invention.

[0101] The embodiments of FIGS. 12 to 14 differ from the embodiments of FIGS. 6 to 11 in that the output of each micro LED (120) is controlled differently in the step of outputting a preset pattern.

[0102] Referring to FIGS. 6 and FIGS. 12 to 14, the control unit (300) can control the light source unit (100) so that each micro LED (120) emits light of different brightness. For example, the control unit (300) can control the light source unit (100) so that each micro LED (120) corresponding to (X2, Y2), (X3, Y2), (X4, Y2), (X4, Y3), (X4, Y4) is turned off, each micro LED (120) corresponding to (X3, Y3), (X2, Y4), (X3, Y4) emits light having a first brightness, each micro LED (120) corresponding to (X2, Y3) emits light having a second brightness, and the remaining micro LEDs (120) emit light having a third brightness. Accordingly, the photoresist placed in each exposure area (EA) is cured to different degrees, so that a stepped photoresist pattern with various heights can be obtained as shown in FIG. 14. That is, the exposure device (1) can obtain a photoresist pattern similar to that obtained when using a halftone mask by individually controlling each micro LED (120).

[0103] The photoresist pattern of FIG. 14 is an example, and the preset pattern output by the light source unit (100) and the shape of the photoresist pattern obtained through it are not limited to FIG. 14.

[0104] In some embodiments, the control unit (300) may control the light source unit (100) to output a first preset pattern for a first preset time and output a second preset pattern for a second preset time. The light from each micro LED (120) may have the same brightness as in the embodiments of FIGS. 9 and 10, or different brightness as in the embodiments of FIGS. 12 and 13. For example, the first preset pattern may be the preset pattern of FIG. 9, and the second preset pattern may be the preset pattern of FIG. 12.

[0105] A method for manufacturing a display device using an exposure device (1) is described in detail below in FIGS. 15 to 20.

[0106] FIGS. 15 to 20 are drawings illustrating a method for manufacturing a display device according to an embodiment of the present invention.

[0107] The exposure device (1) can be used in processes requiring complex pattern forming, for example, processes for manufacturing display devices. The display device includes, but is not limited to, various types of display devices such as, for example, Liquid Crystal Display (LCD) and Organic Light Emitting Display (OLED). The following method for manufacturing a display device can be performed using the exposure device (1) of FIG. 1.

[0108] FIG. 15 is a drawing illustrating a method for manufacturing a display device according to one embodiment of the present invention.

[0109] Referring to FIG. 15, a method for manufacturing a display device comprises the steps of: stacking at least one material layer on a base substrate (11) (S201); applying a photosensitive material on at least one material layer (S202); individually controlling the light intensity of a plurality of micro LEDs (120) to output a preset pattern (S203); exposing the photosensitive material (S204); removing a portion of the photosensitive material (S205); and etching a first pattern on at least one material layer (S206). The photosensitive material may be a photoresist (PR).

[0110] The step of individually controlling the light intensity of a plurality of micro LEDs (120) may include at least one of the steps of individually controlling the on or off of each micro LED (120), individually controlling the driving time of each micro LED (120), or outputting a first preset pattern for a first preset time and outputting a second preset pattern for a second preset time.

[0111] A method for manufacturing a display device may further include a step (S207) of removing a portion of the remaining photosensitive material and a step (S208) of etching a second pattern onto at least one material layer. Here, at least one material layer comprises a first layer (L1) and a second layer (L2) sequentially stacked from below, a first pattern is formed on the first layer (L1) and the second layer (L2), and a second pattern may be formed on the second layer (L2).

[0112] FIGS. 16 to 20 illustrate a process of performing halftone etching by the method of manufacturing a display device of FIG. 15, but is not limited thereto.

[0113] Referring to FIG. 16, the target substrate (10) may include a base substrate (11) and a first layer (L1), a second layer (L2), and a photoresist (PR) sequentially stacked on the base substrate (11).

[0114] The first layer (L1) may consist of at least one layer. For example, the first layer (L1) may include a barrier layer, a buffer layer, gate insulating films and interlayer insulating films, a semiconductor layer for a thin-film transistor structure, an active layer (123), an electrode, etc.

[0115] The second layer (L2) is disposed on the first layer (L1). For example, the second layer (L2) may be a material layer for an oxide semiconductor layer.

[0116] A photoresist (PR) is applied on the second layer. As the control unit (300) of the exposure device (1) controls the micro LED array (MLA) so that the amount of light or the time of light emitted from each micro LED (120) varies, the photoresist (PR) can be divided into a non-exposure area (NEA), a first exposure area (EA1), and a second exposure area (EA2). The non-exposure area (NEA) is an area where the micro LED (120) placed on the upper side is turned off. The first exposure area (EA1) and the second exposure area (EA2) are areas where the micro LED (120) placed on the upper side is turned on. The amount of light or the time of light of the micro LED (120) placed on the upper side of the first exposure area (EA1) may be smaller than the amount of light or the time of light of the micro LED (120) placed on the upper side of the second exposure area (EA2).

[0117] Referring to FIG. 17, a portion of the exposed photoresist (PR) is removed by a developing process. Specifically, when the photoresist (PR) is a positive photoresist (PR), a portion of the photoresist (PR) placed in the non-exposed area remains intact, a portion of the photoresist (PR) placed in the first exposure area (EA1) is removed, and a portion of the photoresist (PR) placed in the second exposure area (EA2) can be completely removed. In other words, a portion of the photoresist (PR) placed in the first exposure area (EA1) remains up to a first height (h1), and a portion of the photoresist (PR) placed in the second exposure area (EA2) can remain up to a second height (h2) which is greater than the first height (h1).

[0118] Referring to FIG. 18, the remaining photoresist (PR) can be used as a mask to etch the first layer (L1) and the second layer (L2) such that the portions placed in the second exposure area (EA2) form a first pattern. In one embodiment, the first layer (L1) and the second layer (L2) can be etched by different etching methods. For example, the second layer (L2) can be etched using a wet etching method, and the first layer (L1) can be etched using a dry etching method. Depending on the degree of etching, an opening may be formed in the first layer (L1), and a groove or trench-shaped pattern may be formed in the second layer (L2). The first pattern can be formed in various shapes and is not limited to FIG. 18.

[0119] Referring to FIGS. 19 and 20, a portion of the remaining photoresist (PR) is removed by an ashing process. The remaining photoresist (PR) placed in the first exposure area (EA1) can be completely removed. Accordingly, a portion of the second layer (L2) placed in the non-exposure area (NEA) is not exposed, but a portion of the second layer (L2) placed in the first exposure area (EA1) can be exposed. The exposed second layer (L2) in the first exposure area (EA1) can be etched again to form a second pattern.

[0120] FIGS. 21 to 24 are drawings illustrating an exposure apparatus according to another embodiment of the present invention and a method for manufacturing a display device using the same.

[0121] Referring to FIGS. 21 to 24, unlike the embodiments of FIGS. 1 and FIG. 20, the exposure device (1a) can also be used in a deposition process. The deposition process may be, for example, a process for depositing an organic layer of an organic light-emitting display device.

[0122] In the following description, the target substrate (10a) may be a substrate on which a deposition source (32) evaporated by exposure is deposited. The target substrate (10a) may include a base substrate and a plurality of layers stacked to form a TFT on the base substrate.

[0123] In the following description, the donor substrate (30) refers to a substrate on which a deposition source (32) is disposed. The donor substrate (30) may include a base substrate (31) and a deposition source (32) stacked on the base substrate (31). The donor substrate (30) may include a material with high thermal conductivity, for example, a metal material.

[0124] Referring to FIG. 21, the exposure device (1a) may include a light source unit (100), a substrate transfer unit (200a), and a control unit (300).

[0125] The light source unit (100) is positioned below the substrate transfer unit (200a). Accordingly, during deposition, the light source unit (100), the donor substrate (30), and the target substrate (10a) can be positioned so as to overlap in order from below. The light source unit (100) may include a light source unit substrate (110), a micro LED array (MLA), and a light-blocking member (130). Since the configuration and operation of the light source unit (100) are substantially the same or similar to the embodiments of FIGS. 1 to 19, redundant descriptions below are omitted.

[0126] The substrate transfer unit (200a) transfers the donor substrate (30) coated with a deposition source (32) between the light source unit (100) and the target substrate (10a). The substrate transfer unit (200a) can transfer the donor substrate (30) so that the donor substrate (30) is positioned between the light source unit (100) and the target substrate (10a) during deposition. In one embodiment, the substrate transfer unit (200a) includes a rail unit that supports both edges of the lower surface of the donor substrate (30), so that the lower surface of the donor substrate (30) is sufficiently exposed to light emitted from the light source unit (100). The rail shape of FIG. 21 is exemplary, and the substrate transfer unit (200a) includes any transfer device capable of exposing the lower surface of the donor substrate (30) and transferring it in at least one of the first direction (X) to the third direction (Z). In one embodiment, the substrate transfer unit (200a) transfers the loaded donor substrate (30) in a first direction (X), but is not limited thereto. In some embodiments, the exposure device (1a) may further include at least one of a light source moving unit that moves the light source unit (100) or a target substrate (10a) transfer unit (200) that transfers the target substrate (10a). The light source moving unit and the target substrate (10a) transfer unit (200) may be controlled by a control unit (300).

[0127] The control unit (300) controls the light source unit (100) and the substrate transfer unit (200a). Since the individual operation of the micro LED (120) by the control unit (300) is substantially the same or similar to the embodiment of FIGS. 1 to 20, redundant descriptions below are omitted.

[0128] Referring to FIG. 21, the method for manufacturing a display device includes the steps of transferring a first donor substrate (30_1) (S301), forming a first deposition pattern on a target substrate (10a) (S302), replacing the first donor substrate (30_1) with a second donor substrate (30_2) (S303), and forming a second deposition pattern on the target substrate (10a) (S304).

[0129] The method for manufacturing a display device may further include a step of determining whether the target substrate (10a), the donor substrate (30), and / or the light source unit (100) are aligned.

[0130] A method for manufacturing a display device will be described in detail below with reference to FIGS. 21 to 24.

[0131] First, the control unit (300) controls the substrate transfer unit (200a) so that the first donor substrate (30_1) is positioned at an appropriate location for deposition. The first donor substrate (30_1) may include a first deposition source (32_1).

[0132] When the first donor substrate (30_1) is transferred to a position for deposition, the control unit (300) determines whether the target substrate (10a), the first donor substrate (30_1), and / or the light source unit (100) are aligned.

[0133] When it is determined that alignment is achieved, the control unit (300) controls the light source unit (100) to expose the first donor substrate (30_1) to form a first deposition pattern on the target substrate (10a). Specifically, the control unit (300) controls the light source unit (100) to output a first preset pattern. The first preset pattern may be output for a first exposure time. The first exposure time may be sufficient time for the first deposition pattern to be formed on the target substrate (10a). The first preset pattern may be a pattern in which some of the plurality of micro LEDs (120) are turned on at predetermined intervals, as shown in FIG. 23, but is not limited thereto.

[0134] As each micro LED (120) is individually turned on or off, the deposition source (32) may be divided into a deposition area and a non-deposition area. The deposition area may be the area where the micro LED (120) is turned on, and the non-deposition area may be the area where the micro LED (120) is turned off. A portion of the deposition source (32) placed in the deposition area may evaporate and be deposited on the target substrate (10a), and a portion of the deposition source (32) placed in the non-deposition area may remain on the donor substrate (30).

[0135] If the first exposure time is longer than the first preset time, the control unit (300) may control the transfer stage to terminate the deposition process or to replace the first donor substrate (30_1) with the second donor substrate (30_2). The second donor substrate (30_2) may include a second deposition source (32_2). The second deposition source (32_2) may include a material that is the same as or different from the first deposition source (32_1).

[0136] Afterwards, the control unit (300) again determines whether the second donor substrate (30_2), the target substrate (10a), and the light source unit (100) are aligned.

[0137] When it is determined that alignment is achieved, the control unit (300) controls the light source unit (100) to expose the second donor substrate (30_2) to form a second deposition pattern on the target substrate (10a). Specifically, the control unit (300) controls the light source unit (100) to output a second preset pattern. The second preset pattern may be output for a second exposure time. The second preset pattern may be a different pattern from the first preset pattern. Accordingly, a deposition pattern may be formed on the target substrate (10a) such that different materials are arranged so as not to overlap.

[0138] In some embodiments, unlike that shown in FIG. 23, the second preset pattern is the same pattern as the first preset pattern, and a deposition pattern may be formed on the target substrate (10a) such that at least a portion of different materials overlap.

[0139] If the second exposure time is longer than the second preset time, the control unit (300) may terminate the deposition process or replace the second donor substrate (30_2) with the third donor substrate (30).

[0140] As each micro LED (120) is driven individually, the exposure device (1a) does not require a mask for deposition, such as an FMM, when performing the deposition process.

[0141] Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention may be implemented in other specific forms without changing the technical concept or essential features thereof. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. Explanation of the symbols

[0142] 1: Exposure device 10: Target substrate 100: Light source 200: Substrate transfer unit 300: Control unit 400: Sensing unit

Claims

Claim 1 A light source unit comprising a plurality of micro LEDs arranged in a matrix form on one surface of a light source substrate for providing light for exposure; a substrate transfer unit for transferring a target substrate including alignment marks; and a control unit for controlling at least one of the light source unit and the substrate transfer unit;and includes a sensing unit disposed below the light source unit and sensing the alignment mark, and the control unit assigns a coordinate or address to each micro LED and individually controls the light intensity of each micro LED according to a preset pattern based on the coordinate or address, and the control unit turns off the first group of micro LEDs among the plurality of micro LEDs, emits light with a first brightness from the second group of micro LEDs, emits light with a second brightness from the third group of micro LEDs, and emits light with a third brightness from the fourth group of micro LEDs, and each micro LED includes a first semiconductor layer disposed on one surface of the light source unit substrate, an active layer disposed on the first semiconductor layer, a second semiconductor layer disposed on the active layer, and a reflector disposed to surround a portion of the side and top surfaces of the second semiconductor layer, and the light source unit further includes a plurality of micro lenses and a light-blocking member disposed on the other surface facing the one surface of the light source unit substrate, and in the thickness direction of the light source unit substrate, each of the plurality of micro lenses is a micro LED corresponding thereto among the plurality of micro LEDs and An exposure device comprising: overlapping, wherein the light-blocking member is positioned between the plurality of micro-lenses, wherein the first semiconductor layer is in contact with one surface of the light source substrate, wherein the plurality of micro-lenses and the light-blocking member are located in the same layer, wherein the control unit receives information regarding alignment status from the sensing unit to determine whether the target substrate is aligned, wherein if the target substrate is not aligned to the correct position, the control unit controls the substrate transfer unit to align the target substrate to the correct position, and if the target substrate is aligned to the correct position, the control unit controls the light source unit to output the preset pattern, and wherein the sensing unit does not overlap with the plurality of micro-LEDs in the thickness direction of the target substrate. Claim 2 An exposure device according to claim 1, wherein the size of each micro LED is 100 μm or less. Claim 3 An exposure device according to claim 1, wherein the average pitch between each micro LED is 5000 μm or less. Claim 4 An exposure device according to claim 1, wherein the emission wavelength of each micro LED is 200 nm to 500 nm. Claim 5 delete Claim 6 An exposure device according to claim 1, wherein the reflector has a shape of upper narrower and lower light, and the side slope of the reflector is 40 to 90 degrees. Claim 7 delete Claim 8 delete Claim 9 delete Claim 10 An exposure apparatus according to claim 1, wherein the distance between the light source unit and the target substrate loaded on the substrate transfer unit during exposure is 500 μm or less. Claim 11 In claim 1, the control unit is an exposure device that individually controls the on or off of each micro LED. Claim 12 In claim 1, the control unit is an exposure device that individually controls the driving time of each micro LED. Claim 13 An exposure device according to claim 1, wherein the control unit controls the light source unit to output a first preset pattern during a first preset time, and when it is determined that the first preset time has elapsed, controls the light source unit to output a second preset pattern different from the first preset pattern. Claim 14 A light source unit comprising a plurality of unit light-emitting cells arranged in a matrix form on one surface of a light source substrate for providing light for exposure; a substrate transfer unit for transferring a target substrate including alignment marks; and a control unit for controlling at least one of the light source unit and the substrate transfer unit;The light source unit includes a sensing unit disposed below the light source unit and sensing the alignment mark, and the control unit assigns coordinates or addresses to each unit light-emitting cell and individually controls the amount of light of each unit light-emitting cell according to a preset pattern based on the coordinates or addresses, and the control unit controls the unit light-emitting cells of the plurality of unit light-emitting cells to turn off the unit light-emitting cells of the first group, to emit light with a first brightness, to emit light with a second brightness, to emit light with a third brightness, and to emit light with a fourth group of unit light-emitting cells. The plurality of unit light-emitting cells are micro LEDs comprising a first semiconductor layer disposed on one surface of the light source unit substrate, an active layer disposed on the first semiconductor layer, a second semiconductor layer disposed on the active layer, and a reflector disposed to surround a portion of the side and top surfaces of the second semiconductor layer. The light source unit further includes a plurality of micro lenses and a light-blocking member disposed on the other surface facing the one surface of the light source unit substrate, and in the thickness direction of the light source unit substrate, each of the plurality of micro lenses An exposure device comprising: a plurality of micro-LEDs overlapping with a corresponding micro-LED among the plurality of micro-LEDs; a light-blocking member positioned between the plurality of micro-lenses; a first semiconductor layer in contact with one surface of the light source substrate; the plurality of micro-lenses and the light-blocking member positioned in the same layer; a control unit receiving information regarding alignment status from the sensing unit to determine whether the target substrate is aligned; if the target substrate is not aligned to the correct position, controlling the substrate transfer unit to align the target substrate to the correct position; and if the target substrate is aligned to the correct position, controlling the light source unit to output the preset pattern; wherein the sensing unit does not overlap with the plurality of micro-LEDs in the thickness direction of the target substrate. Claim 15 delete Claim 16 delete Claim 17 delete Claim 18 delete Claim 19 delete Claim 20 delete

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