Display device

Abstract

A display device is provided, which includes a driving substrate, a barrier layer provided on an upper surface of the driving substrate and including a plurality of recesses, a micro-semiconductor light-emitting device provided in each of the plurality of recesses, and a side reflection structure provided in the barrier layer and adjacent to a side wall of each of the plurality of recesses.

Description

Technical Field

[0001] Example embodiments of the present disclosure relate to a display device having a reflective structure, and more particularly, to a display device using a semiconductor light emitting device as a pixel. Background Art

[0002] Since light-emitting diodes (LEDs) consume less power and are environmentally friendly, industrial demand for them is increasing, and LEDs have also been used as pixels for display devices and as backlights for lighting devices or liquid crystal displays (LCDs). Recently, micro-LED display devices using micro-cell LED chips as pixels have been developed. When manufacturing display devices using micro-cell LED chips, laser lift-off or pick-and-place methods are used as methods for transferring micro-LEDs. However, using this method, productivity decreases as the size of the micro-LEDs decreases and the size of the display device increases. Summary of the Invention

[0003] One or more example embodiments provide a display device manufactured to have a large area using a fluid self-assembly method.

[0004] One or more example embodiments also provide a display device having a reflective structure, which can be manufactured in a fluid self-assembly manner, reduces crosstalk between adjacent pixels, and improves light efficiency.

[0005] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of example embodiments of the disclosure.

[0006] According to one aspect of an example embodiment, there is provided a display device including a driving substrate, a barrier layer disposed on an upper surface of the driving substrate and including a plurality of recesses, a micro semiconductor light emitting device disposed in each of the plurality of recesses, and a side reflection structure disposed in the barrier layer and provided adjacent to a sidewall of each of the plurality of recesses.

[0007] The side reflection structure may be disposed such that a sidewall of the recess is disposed between the micro semiconductor light emitting device and the side reflection structure, and a distance from the sidewall of the recess to the side reflection structure may be in a range from 0.1 μm to 50 μm.

[0008] The width of the side reflection structure in a direction parallel to the upper surface of the driving substrate may be in a range from 1 μm to a value smaller than a width of the micro semiconductor light emitting device.

[0009] The side reflective structure may include a metallic material.

[0010] The side reflective structures may extend from the upper surface of the barrier layer to the lower surface of the barrier layer.

[0011] The side reflective structure may be configured to reflect light emitted from the micro semiconductor light emitting device.

[0012] The display device may further include a lower reflection structure having a hydrophilic surface and disposed at a bottom side of each of the plurality of recesses.

[0013] An area of ​​the low reflection structure may be greater than an area of ​​each of the plurality of recesses, and a portion of the barrier layer may be disposed over a portion of an upper surface of the low reflection structure.

[0014] The lower reflection structure may be disposed such that an upper surface of the lower reflection structure contacts a lower surface of the side reflection structure.

[0015] The low reflection structure may include a reflective metal layer and an insulating layer disposed on the reflective metal layer, the insulating layer having a hydrophilic surface.

[0016] The thickness of the reflective metal layer in a normal direction of the upper surface of the driving substrate may be in a range of 50 nm to 1 μm.

[0017] The reflective metal layer may include a plurality of reflective metal layers respectively disposed under the plurality of recesses, and a single insulating layer may be disposed on the upper surface of the driving substrate and on the plurality of reflective metal layers.

[0018] The reflective metal layer may include at least one of aluminum (Al) and silver (Ag).

[0019] The low reflection structure may include first and second dielectric layers that are repeatedly and alternately stacked, the first dielectric layer may have a first refractive index and the second dielectric layer may have a second refractive index different from the first refractive index.

[0020] The thickness of the lower reflective structure in a normal direction of the upper surface of the driving substrate may be in a range of 500 nm to 2 μm.

[0021] The display device may further include a hydrophobic pattern disposed on an upper surface of the barrier layer and including the same material as that of the side reflective structure.

[0022] A lower surface of the micro semiconductor light emitting device in contact with a bottom surface of a corresponding one of the plurality of recesses may have hydrophilicity.

[0023] The micro semiconductor light emitting device may include a first electrode and a second electrode disposed on an upper surface thereof.

[0024] Each of the plurality of recesses may include a first capture region having a space in which the micro semiconductor light emitting device moves, and a second capture region having a shape and size in which the micro semiconductor light emitting device is seated, the second capture region being connected to the first capture region.

[0025] The size of the first capture region may be set so that two or more micro semiconductor light emitting devices do not enter each of the plurality of recesses.

[0026] The width of the second trapping region may be in the range of 100% to about 105% of the width of the micro semiconductor light emitting device.

[0027] The display device may further include a wavelength conversion layer configured to convert a wavelength of light emitted from the micro semiconductor light emitting device.

[0028] According to another aspect of the example embodiment, a display device is provided, which includes a driving substrate, a plurality of micro-semiconductor light-emitting devices arranged on an upper surface of the driving substrate, a protective layer arranged on the upper surface of the driving substrate and the plurality of micro-semiconductor light-emitting devices, and a side reflection structure arranged within the protective layer and adjacent to a periphery of each of the plurality of micro-semiconductor light-emitting devices.

[0029] The width of the side reflection structure in a direction parallel to the upper surface of the driving substrate may be in a range from 1 μm to a value smaller than the width of the micro semiconductor light emitting device.

[0030] The side reflective structure may include a metallic material.

[0031] The side reflection structure may extend from the upper surface of the protection layer to the lower surface of the protection layer.

[0032] The display device may further include a lower reflection structure disposed between each of the plurality of micro semiconductor light emitting devices and the driving substrate.

[0033] The low reflection structure may include a reflective metal layer and an insulating layer disposed on the reflective metal layer.

[0034] Each of the plurality of micro semiconductor light emitting devices may include a first electrode and a second electrode disposed on the same surface.

[0035] The reflective metal layer may include a first reflective metal layer electrically connected to the first electrode of each of the plurality of micro semiconductor light emitting devices and a second reflective metal layer electrically connected to the second electrode of each of the plurality of micro semiconductor light emitting devices.

[0036] According to another aspect of the example embodiments, there is provided a display device including: a driving substrate; a barrier layer disposed on an upper surface of the driving substrate and including a plurality of recesses, the barrier layer having a flexible polymer material; a micro semiconductor light emitting device disposed in each of the plurality of recesses; and a side reflection structure included in the barrier layer and provided adjacent to a sidewall of each of the plurality of recesses. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The above and / or other aspects, features and advantages of example embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0038] Figure 1 is a cross-sectional view schematically illustrating a structure of a display device according to an example embodiment;

[0039] Figure 2 is a plan view schematically showing a structure of a display device according to an example embodiment;

[0040] Figure 3 It is shown in Figure 1 A cross-sectional view of the arrangement of a side reflection structure and a bottom reflection structure for a micro semiconductor light emitting device in the display device shown;

[0041] Figure 4A 、 Figure 4B 、 Figure 4C and Figure 4D It shows the manufacturing Figure 1 A cross-sectional view of the method of displaying the device shown;

[0042] Figure 5 is a cross-sectional view schematically showing the structure of a barrier layer, wherein the upper surface of the barrier layer is treated to have hydrophobicity;

[0043] Figure 6 is a cross-sectional view schematically illustrating a structure of a display device according to another example embodiment;

[0044] Figure 7A 、 Figure 7B 、 Figure 7C 、 Figure 7D 、 Figure 7E and Figure 7F is a cross-sectional view illustrating a method of manufacturing a display device, showing wiring between a driving substrate and a micro semiconductor light emitting device;

[0045] Figure 8 is a cross-sectional view schematically illustrating a structure of a display device according to another example embodiment;

[0046] Figure 9 It shows Figure 8A cross-sectional view of the layer structure of the lower reflective structure shown;

[0047] Figure 10 is a perspective view illustrating a method of aligning a micro semiconductor light emitting device using a fluid self-assembly method;

[0048] Figure 11 Schematically illustrates a scanning process for aligning a micro semiconductor light emitting device;

[0049] Figure 12 is a perspective view showing the shape of a recess provided in a barrier layer of a display device;

[0050] Figure 13 It shows Figure 12 a plan view of the shape of the depression shown;

[0051] Figure 14A 、 Figure 14B and Figure 14C shows various shapes of recesses according to example embodiments;

[0052] Figure 15A 、 Figure 15B 、 Figure 15C 、 Figure 15D 、 Figure 15E and Figure 15F is a cross-sectional view illustrating a method of manufacturing a display device according to another example embodiment;

[0053] Figure 16 is a cross-sectional view schematically illustrating a structure of a display device according to another example embodiment;

[0054] Figure 17 is a cross-sectional view schematically illustrating a structure of a display device according to another example embodiment;

[0055] Figure 18 is a schematic block diagram of an electronic device according to an example embodiment;

[0056] Figure 19 An example in which a display device according to an example embodiment is applied to a mobile device is shown;

[0057] Figure 20 An example in which the display device according to the example embodiment is applied to a vehicle display device is shown;

[0058] Figure 21 An example in which a display device according to an example embodiment is applied to augmented reality glasses or virtual reality glasses is shown;

[0059] Figure 22 shows an example in which the display device according to the example embodiment is applied to a sign; and

[0060] Figure 23 An example in which the display device according to example embodiments is applied to a wearable display is shown. DETAILED DESCRIPTION

[0061] Reference will now be made in detail to the example embodiments shown in the accompanying drawings, in which the same reference numerals refer to the same elements throughout. In this regard, example embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, only embodiments are described below by way of the accompanying drawings to illustrate various aspects. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. Expressions such as "at least one of...", when following a column of elements, modify the entire column of elements, rather than modifying the individual elements in the list. For example, the expression "at least one of a, b, and c" should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0062] Hereinafter, a display device including a reflective structure will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings represent like elements, and in the drawings, the sizes of elements may be exaggerated for clarity and ease of description. The example embodiments described below are merely examples, and various modifications may be made from these embodiments.

[0063] Hereinafter, when a certain component is described as being “on” or “on” another component, the certain component may be directly on the other component, or a third component may be interposed therebetween. A singular expression includes a plural expression unless they are clearly different from each other in context. In addition, when a certain part “includes” a certain component, this means that the part may further include another component rather than excluding the other component unless there is a different disclosure.

[0064] The use of the term "the" and similar referential terms may refer to both the singular and the plural. The steps of the methods described herein may be performed in any suitable order, unless otherwise indicated herein or otherwise clearly contradicted by context, and embodiments of the present disclosure are not limited to the order in which the operations are described.

[0065] Furthermore, terms such as “unit” or “module” disclosed in the specification mean a unit for processing at least one function or operation, and this can be implemented by hardware, software, or a combination thereof.

[0066] The connecting lines or connecting members between components shown in the drawings represent functional connections and / or physical or circuit connections, and in actual devices they may represent various alternative or additional functional connections, physical connections or circuit connections.

[0067] The use of any and all examples, or exemplary language provided herein, is intended merely to better illuminate the inventive concepts and does not pose a limitation on the scope of the inventive concepts unless otherwise claimed.

[0068] Figure 1 is a cross-sectional view schematically showing a structure of a display device 100 according to an example embodiment. Figure 1 The display device 100 may include a driving substrate 110 having a driving circuit, etc., a barrier layer 120 provided on the upper surface of the driving substrate 110 and having a plurality of recesses 150, a micro semiconductor light emitting device 140 provided in each recess 150, and a side reflection structure 132 provided inside the barrier layer 120 to be adjacent to and surround the side wall of each recess 150.

[0069] The micro-semiconductor light emitting device 140 may include various types of light emitting devices having micron-scale dimensions. For example, the width, diameter, or thickness of the micro-semiconductor light emitting device 140 may be about 1000 μm or less, or about 200 μm or less, or about 100 μm or less, or about 50 μm or less. The micro-semiconductor light emitting device 140 may include a semiconductor light emitting device such as a light emitting diode (LED) or a vertical cavity surface emitting laser (VCSEL).

[0070] The micro semiconductor light emitting device 140 may include a first semiconductor layer 145, an active layer 146, and a second semiconductor layer 147. The first semiconductor layer 145 and the second semiconductor layer 147 may be electrically doped to opposite types. For example, the first semiconductor layer 145 may be doped to n-type and the second semiconductor layer 147 may be doped to p-type, or the first semiconductor layer 145 may be doped to p-type and the second semiconductor layer 147 may be doped to n-type. The active layer 146 may have, for example, a quantum well structure or a multi-quantum well structure.

[0071] In addition, the micro-semiconductor light-emitting device 140 may include a first electrode 148 and a second electrode 149 provided on the same surface. The first electrode 148 may be electrically connected to the first semiconductor layer 145, and the second electrode 149 may be electrically connected to the second semiconductor layer 147. The first electrode 148 and the second electrode 149 may be arranged symmetrically about the central axis of the micro-semiconductor light-emitting device 140, so that even if the micro-semiconductor light-emitting device 140 is rotated about the central axis in the recess 150, the relative positions of the first electrode 148 and the second electrode 149 can be fixed. For example, the second electrode 149 may be provided in the central portion of the upper surface of the micro-semiconductor light-emitting device 140, and the first electrode 148 may be provided in the peripheral portion of the upper surface. The above-mentioned shape of the micro-semiconductor light-emitting device 140 is an example and is not limited thereto.

[0072] A driving circuit including a thin film transistor (TFT) for driving the micro semiconductor light emitting device 140 may be provided in the driving substrate 110. In addition, the display device 100 may further include via holes and wiring arranged to electrically connect the first electrode 148 and the second electrode 149 of the micro semiconductor light emitting device 140 to the driving circuit in the driving substrate 110.

[0073] A barrier layer 120 including recesses 150 is provided on the drive substrate 110 to accurately position the micro-semiconductor light-emitting devices 140 on the upper surface of the drive substrate 110. Micro-semiconductor light-emitting devices 140 can be positioned in each recess 150 using a fluidic self-assembly method, which will be described later. By guiding the micro-semiconductor light-emitting devices 140 into the recesses 150 of the barrier layer 120, the micro-semiconductor light-emitting devices 140 can be two-dimensionally aligned at accurate positions on the drive substrate 110.

[0074] The recess 150 may have an area larger than that of the micro-semiconductor light-emitting device 140 to accommodate the micro-semiconductor light-emitting device 140. For example, the area of ​​the recess 150 may be larger than that of the micro-semiconductor light-emitting device 140 and less than twice the area of ​​the micro-semiconductor light-emitting device 140. Thus, one micro-semiconductor light-emitting device 140 may be disposed in one recess 150. Furthermore, the depth of the recess 150 may be similar to the thickness of the micro-semiconductor light-emitting device 140. For example, the depth of the recess 150 may be 0.8 times or greater and 1.5 times or less than the thickness of the micro-semiconductor light-emitting device 140. The recess 150 may have a shape similar to that of the micro-semiconductor light-emitting device 140, such as a polygon or a circle.

[0075] The bottom surface 150b of the recess 150 can be hydrophilic, so that when the micro-semiconductor light-emitting device 140 is placed in the recess 150 using a fluidic self-assembly method, the upper surface of the micro-semiconductor light-emitting device 140, in which the first electrode 148 and the second electrode 149 are disposed, faces the exterior of the recess 150. Specifically, the bottom surface 150b of the recess 150, which contacts the lower surface of the micro-semiconductor light-emitting device 140, can include a dielectric material having a smooth surface to have high hydrophilicity. For example, the root mean square (RMS) roughness of the bottom surface 150b of the recess 150 can be approximately 50 nm or less, or approximately 10 nm or less. In addition, the lower surface of the micro-semiconductor light-emitting device 140, which contacts the bottom surface 150b of the recess 150, can also be hydrophilic and can have an RMS roughness of approximately 50 nm or less, or approximately 10 nm or less. Thus, the micro-semiconductor light-emitting device 140 can be guided so that the hydrophilic lower surface faces the hydrophilic bottom surface 150b of the recess 150.

[0076] The barrier layer 120 may include a flexible polymer material. For example, the barrier layer 120 may include at least one of an acrylic polymer, a silicone-based polymer, and an epoxy-based polymer. Furthermore, the barrier layer 120 may also include a photosensitive material. When the barrier layer 120 includes a photosensitive material, the recess 150 may be formed by photolithography. When the barrier layer 120 does not include a photosensitive material, the recess 150 may be formed by etching and molding. Because the barrier layer 120 includes a flexible material, even when slight pressure is applied to the barrier layer 120 to align the micro-semiconductor light-emitting device 140 in the recess 150, the barrier layer 120 can return to its original state. Furthermore, because the polymer material can be formed with a constant thickness over a large area through a general coating process, the barrier layer 120 can be formed on a large-area drive substrate 110.

[0077] The micro-semiconductor light emitting device 140 disposed in each recess 150 can be used as a pixel of the display device 100. The side reflection structure 132 can be configured to reflect the light emitted in the lateral direction of each micro-semiconductor light emitting device 140 to prevent or reduce crosstalk between adjacent pixels. To this end, the side reflection structure 132 can be configured to surround the side surface of each micro-semiconductor light emitting device 140 and prevent light from being transmitted. For example, the side reflection structure 132 can be disposed inside the barrier layer 120 to surround the sidewall 150s of each recess 150. Figure 1 , the side reflective structure 132 is shown as completely penetrating the barrier layer 120 and extending vertically from the upper surface to the lower surface of the barrier layer 120, but the embodiment is not limited thereto. For example, the side reflective structure 132 may not penetrate the barrier layer 120, such that the lower surface of the side reflective structure 132 is surrounded by the lower portion of the barrier layer 120. In addition, the side reflective structure 132 may be embedded in the barrier layer 120, such that the upper surface of the side reflective structure 132 is surrounded by the upper portion of the barrier layer 120.

[0078] The side reflective structure 132 may include a metal material such as aluminum (Al) or silver (Ag), which has excellent reflectivity with respect to light emitted from the micro-semiconductor light-emitting device 140 and hardly transmits the light emitted from the micro-semiconductor light-emitting device 140. Since such a metal material is generally hydrophobic, the side reflective structure 132 is disposed so as not to directly contact the bottom surface 150b of the recess 150. If the hydrophilic bottom surface 150b of the recess 150 contacts the side reflective structure 132, the surface energy of the bottom surface 150b may change and the surface roughness may increase, thereby preventing the hydrophilic lower surface of the micro-semiconductor light-emitting device 140 from being disposed to face the hydrophilic bottom surface 150b of the recess 150. For example, the side reflective structure 132 may be disposed in the barrier layer 120 such that the sidewall 150s of the recess 150 is disposed between the micro-semiconductor light-emitting device 140 and the side reflective structure 132.

[0079] The display device 100 may further include a lower reflective structure 131 adjacent to or disposed on the bottom side of each recess 150. The lower reflective structure 131 may face the lower surface of the micro-semiconductor light-emitting device 140 and reflect light emitted downward from the micro-semiconductor light-emitting device 140 to improve light utilization efficiency. Therefore, the use of the lower reflective structure 131 may increase the brightness of the display device 100 and reduce power consumption.

[0080] The upper surface of the lower reflective structure 131 may be the bottom surface 150b of the recess 150. As described above, the bottom surface 150b of the recess 150 has hydrophilicity. Therefore, the lower reflective structure 131 may be configured to have a hydrophilic surface. To this end, the lower reflective structure 131 may include a reflective metal layer 131a disposed on the upper surface of the drive substrate 110 and an insulating layer 131b disposed to cover the reflective metal layer 131a and having a hydrophilic surface. For example, the insulating layer 131b may include a dielectric material that is transparent to visible light, and the upper surface of the insulating layer 131b may have an RMS roughness of approximately 50 nm or less or 10 nm or less. In addition, the reflective metal layer 131a may include at least one of aluminum (Al) and silver (Ag).

[0081] To improve light utilization efficiency, the lower reflective structure 131 may have an area larger than that of the recess 150. Therefore, the lower reflective structure 131 may partially overlap with the barrier layer 120. For example, a portion of the barrier layer 120 may be disposed on a portion of the upper surface of the lower reflective structure 131. Furthermore, the lower reflective structure 131 may extend laterally such that a portion of the upper surface of the lower reflective structure 131 contacts the lower surface of the side reflective structure 132. In this case, the side reflective structure 132 may extend from the upper surface of the barrier layer 120 to the upper surface of the lower reflective structure 131, specifically, by extending vertically through the interior of the barrier layer 120 to the upper surface of the insulating layer 131b.

[0082] Figure 2 1 is a plan view schematically showing a structure of a display device 100 according to an exemplary embodiment. Figure 2, the micro-semiconductor light-emitting devices 140 may be respectively arranged in the two-dimensional recesses 150. Therefore, the display device 100 may include the micro-semiconductor light-emitting devices 140 arranged in two dimensions. The shape of the recess 150 may be the same as the shape of the micro-semiconductor light-emitting device 140, and the area of ​​the recess 150 may be larger than the area of ​​the micro-semiconductor light-emitting device 140. Therefore, there may be a gap between the side wall 150s of the recess 150 and the side surface of the micro-semiconductor light-emitting device 140. The side reflection structure 132 may surround the side wall 150s of the recess 150 and may have an inner surface with the same shape as the shape of the recess 150 and the micro-semiconductor light-emitting device 140. In Figure 2 In the embodiment, the inner surface of the recess 150, the side surface of the micro-semiconductor light emitting device 140, and the inner surface of the side reflective structure 132 are shown as having a quadrilateral shape, but the embodiment is not limited thereto. For example, the inner surface of the recess 150, the side surface of the micro-semiconductor light emitting device 140, and the inner surface of the side reflective structure 132 may have a circular shape. Since the side reflective structure 132 is provided on the outer side of the side wall 150s of the recess 150, the total length of the inner surface of the side reflective structure 132 is greater than the total length of the side wall 150s of the recess 150.

[0083] Figure 3 It is shown in Figure 1 FIG. 1 is a cross-sectional view of the arrangement of the side reflection structure 132 and the lower reflection structure 131 for a micro semiconductor light emitting device in the display device 100. Figure 3 Since the light emitted in the lateral direction by the micro-semiconductor light-emitting device 140 is reflected by the side reflection structure 132, crosstalk between adjacent pixels of the display device 100 can be prevented or reduced. In addition, since a portion of the light reflected by the side reflection structure 132 can contribute to image formation, the light utilization efficiency of the display device 100 can also be improved. Since the light emitted in the downward direction by the micro-semiconductor light-emitting device 140 is reflected in the upward direction by the lower reflection structure 131 to contribute to image formation, the light utilization efficiency of the display device 100 can be further improved.

[0084] The side reflective structure 132 is disposed within the barrier layer 120 such that the hydrophilic bottom surface 150b of the recess 150 is not covered by the side reflective structure 132. For example, the side reflective structure 132 may be disposed within the barrier layer 120 such that the sidewall 150s of the recess 150 is disposed between the micro-semiconductor light-emitting device 140 and the side reflective structure 132. If the side reflective structure 132 is too far from the sidewall 150s of the recess 150, light may be absorbed by the barrier layer 120, thereby increasing light loss. Alternatively, if the side reflective structure 132 is too close to the sidewall 150s of the recess 150, the likelihood of damage to the sidewall 150s may increase. In this regard, a horizontal distance t3 from the sidewall 150s of the recess 150 to the side reflective structure 132 may be within a range of approximately 0.1 μm to approximately 50 μm. Here, the horizontal direction is a direction parallel to the upper surface of the drive substrate 110.

[0085] Taking into account the reflectivity of the side reflection structure 132 and the overall structure and size of the display device 100, the width t2 of the side reflection structure 132 in a direction parallel to the upper surface of the drive substrate 110 can be determined to be within a range from about 1 μm to a value less than the width of the micro-semiconductor light-emitting device 140 in the horizontal direction. The thickness t1 of the reflective metal layer 131a of the lower reflection structure 131 in the normal direction to the upper surface of the drive substrate 110 can also be within a range from about 50 nm to about 1 μm.

[0086] Figures 4A to 4D It shows the manufacturing Figure 1 A cross-sectional view of a method of manufacturing a display device 100 is shown.

[0087] First, refer to Figure 4A The lower reflective structure 131 may be formed on the driving substrate 110 at a location where the micro semiconductor light emitting device 140 is to be disposed. For example, after sequentially depositing the metal material of the reflective metal layer 131a and the dielectric material of the insulating layer 131b on the entire area of ​​the upper surface of the driving substrate 110, the metal material of the reflective metal layer 131a and the dielectric material of the insulating layer 131b may be patterned to form the lower reflective structure 131.

[0088] Reference Figure 4B, the barrier layer 120 can be formed on the upper surface of the drive substrate 110. The barrier layer 120 can be formed by stacking a polymer material including a photosensitive material over the entire area of ​​the upper surface of the drive substrate 110. Thereafter, by exposing and patterning the barrier layer 120 using photolithography, recesses 150 can be formed at the locations where the micro-semiconductor light-emitting devices 140 will be disposed. Each recess 150 can be formed to penetrate the barrier layer 120 to expose the lower reflective structure 131. In addition, when forming the recess 150, a groove 151 can be formed around the periphery of the recess 150. The groove 151 can be formed to completely penetrate the barrier layer 120 to expose the lower reflective structure 131, but is not limited thereto. For example, the groove 151 can extend only to the lower portion of the barrier layer 120, rather than completely penetrating the barrier layer 120. The barrier layer 120 having the recess 150 and the groove 151 can also be formed using an etching method or a molding method (instead of photolithography).

[0089] Reference Figure 4C The side reflection structure 132 can be formed by filling the groove 151 with a reflective metal material. As a result, the reflective metal material having hydrophobicity is partially exposed from the upper surface 120a of the barrier layer 120. As a result, the upper surface 120a of the barrier layer 120 can have a hydrophobic surface with increased surface roughness.

[0090] In order to make the upper surface 120a of the barrier layer 120 hydrophobic and have increased surface roughness, a pattern including the same metal material as the side reflection structure 132 may be further formed on the upper surface 120a of the barrier layer 120. For example, Figure 5 is a cross-sectional view schematically showing the structure of the barrier layer 120, wherein the upper surface of the barrier layer 120 is processed to have increased hydrophobicity. Figure 5 A hydrophobic pattern 133 for increasing surface roughness may be formed on the upper surface 120a of the barrier layer 120. The hydrophobic pattern 133 may be formed together when the side reflection structure 132 is formed in the groove 151 and may include the same material as that of the side reflection structure 132.

[0091] Reference Figure 4DA fluidic self-assembly method can be used to position microscopic semiconductor light-emitting devices 140 in recesses 150. For example, liquid and microscopic semiconductor light-emitting devices 140 can be supplied onto barrier layer 120, and an absorber capable of absorbing the liquid can be scanned across barrier layer 120. After the absorber is scanned across barrier layer 120, the remaining microscopic semiconductor light-emitting devices 140 that have not entered recesses 150 can be removed. By repeating this process, microscopic semiconductor light-emitting devices 140 can be positioned in all recesses 150. Because the sidewalls 150s and bottom surface 150b of recess 150 are hydrophilic and the upper surface 120a of barrier layer 120 has either low hydrophilicity or low hydrophobicity, the hydrophilic lower surface of microscopic semiconductor light-emitting device 140 can be directed toward the interior of recess 150, and the hydrophobic first and second electrodes 148 and 149 of microscopic semiconductor light-emitting device 140 can be aligned toward the exterior of recess 150. This fluidic self-assembly method will be described in more detail later.

[0092] After transferring the micro semiconductor light emitting device 140 into the recess 150, further steps may be performed to form an insulating layer covering the micro semiconductor light emitting device 140 and the barrier layer 120, to form wiring electrically connected to the first electrode 148 and the second electrode 149 of the micro semiconductor light emitting device 140 through the insulating layer, and to form a protective layer. This will be described in more detail later.

[0093] Figure 6 is a cross-sectional view schematically showing the structure of a display device 100a according to another exemplary embodiment. Figure 1 and Figures 4A to 4D , the display device 100 is shown as including a separate lower reflective structure 131. Generally, since the electrode pads for electrical connection with the micro semiconductor light emitting device 140 are provided on the upper surface of the driving substrate 110, the reflective metal layer 131a including the metal material may not be formed on the entire area of ​​the upper surface of the driving substrate 110, and the reflective metal layer 131a may be formed only under the micro semiconductor light emitting device 140. The insulating layer 131b does not need to be separately provided on the reflective metal layer 131a. Figure 6 The lower reflective structure 131 of the display device 100a may include a plurality of reflective metal layers 131a respectively arranged under the recess 150 to face the lower surface of the micro semiconductor light emitting device 140, and an insulating layer 131b arranged on the upper surface of the driving substrate 110 to cover the plurality of reflective metal layers 131a.

[0094] 7A to 7F is a cross-sectional view illustrating a method of manufacturing a display device, showing wiring between a driving substrate and a micro semiconductor light emitting device.

[0095] Reference Figure 7A A driving substrate 110 is provided, including an insulating supporting substrate 101 and a driving circuit layer 102 disposed on the supporting substrate 101. The supporting substrate 101 may comprise, for example, glass or a polymer material. The driving circuit layer 102 may include a driving circuit including a TFT, a capacitor, etc. A first electrode pad 103 electrically connected to the source / drain electrodes of the TFT may be disposed on the upper surface of the driving circuit layer 102.

[0096] Reference Figure 7B , the reflective metal layer 131a can be formed on the upper surface of the driving circuit layer 102 so as not to contact the first electrode pad 103, and the insulating layer 131b can be formed to cover both the first electrode pad 103 and the reflective metal layer 131a. The reflective metal layer 131a and the insulating layer 131b form the lower reflective structure 131. According to another exemplary embodiment, when the first electrode pad 103 and the reflective metal layer 131a include the same metal material, the first electrode pad 103 and the reflective metal layer 131a can be formed simultaneously through a single process. For example, after depositing a metal layer on the upper surface of the driving circuit layer 102, the first electrode pad 103 and the reflective metal layer 131a can be formed together through patterning.

[0097] Reference Figure 7C After forming the barrier layer 120 on the upper surface of the driving circuit layer 102, the barrier layer 120 may be patterned to form a recess 150 and a groove 151 surrounding the recess 150. In addition, a via hole 152 may be formed penetrating the barrier layer 120 to expose a portion of the first electrode pad 103. The recess 150, the groove 151, and the via hole 152 may be formed together by patterning the barrier layer 120.

[0098] Thereafter, the side reflection structure 132 may be formed by filling the groove 151 with a metal material, and the conductive metal layer 104 may be formed by filling the via hole 152 with a metal material. The side reflection structure 132 and the conductive metal layer 104 may be formed simultaneously using a metal material having conductivity and reflectivity, such as aluminum or silver. The conductive metal layer 104 may be electrically connected to the first electrode pad 103 through the via hole 152. In addition, the conductive metal layer 104 may extend in a horizontal direction on the upper surface of the barrier layer 120. Due to the conductive metal layer 104 extending on the upper surface of the barrier layer 120, the upper surface of the barrier layer 120 has hydrophobicity. A portion of the side reflection structure 132 may also extend in a horizontal direction on the upper surface of the barrier layer 120.

[0099] Reference Figure 7DThe micro semiconductor light emitting device 140 may be placed in the recess 150 using a fluid self-assembly method. The first electrode 148 and the second electrode 149 of the micro semiconductor light emitting device 140 may be aligned toward the outside of the recess 150 using the fluid self-assembly method.

[0100] Reference Figure 7E , an insulating layer 160 may be formed to completely cover the micro-semiconductor light-emitting device 140 and the barrier layer 120. The insulating layer 160 may include a dielectric material that is transparent to visible light. Furthermore, the insulating layer 160 may be patterned to form a plurality of via holes 153, 154, 155, and 156 that vertically penetrate the insulating layer 160. The via holes 153 and 154 may expose the conductive metal layer 104 through the insulating layer 160, and the via holes 155 and 156 may expose the first electrode 148 and the second electrode 149 of the micro-semiconductor light-emitting device 140 through the insulating layer 160.

[0101] Reference Figure 7F , the via holes 153, 154, 155, and 156 may be filled with a conductive metal material to form wirings 105 and 106 that electrically connect the first electrode 148 and the second electrode 149 to the source / drain electrodes of the TFT in the driving circuit layer 102. In addition, a transparent protective layer 170 covering the insulating layer 160 and the wirings 105 and 106 may be formed.

[0102] Figure 8 is a cross-sectional view schematically showing a structure of a display device 100b according to another exemplary embodiment. Figure 8 , the display device 100b may include a lower reflective structure 131' made only of an insulating dielectric material. Since the lower reflective structure 131' does not include a metal material, it can be provided over the entire upper surface of the drive substrate 110. The remaining configuration of the display device 100b is the same as that of the display devices 100 and 100a described above, and therefore a description thereof is omitted.

[0103] Figure 9 It shows Figure 8 The cross-sectional view of the layer structure of the lower reflective structure 131' is shown. Figure 9, the lower reflection structure 131' may include a first dielectric layer 131a' and a second dielectric layer 131b' that are repeatedly and alternately stacked. The first dielectric layer 131a' may have a first refractive index, and the second dielectric layer 131b' may have a second refractive index different from the first refractive index. In this case, high reflectivity can be obtained by matching the phase of light reflected from the interface between the first dielectric layer 131a' and the second dielectric layer 131b'. Therefore, the lower reflection structure 131' may be a distributed Bragg reflector. The reflectivity of the lower reflection structure 131' may increase as the number of stacking of the first dielectric layer 131a' and the second dielectric layer 131b' increases. Considering the overall structure and size of the display device 100b, the thickness of the lower reflection structure 131' in the normal direction of the upper surface of the driving substrate 110 may be set in the range of about 500nm to about 2μm.

[0104] Figure 10 1 is a perspective view showing a method of aligning a micro semiconductor light emitting device 140 using a fluid self-assembly method. Figure 10 , micro semiconductor light emitting devices 140 may be provided on the upper surface of the barrier layer 120 having the two-dimensionally arranged recesses 150. The micro semiconductor light emitting devices 140 may be directly spread on the barrier layer 120 after the liquid is supplied to the recesses 150 of the barrier layer 120, or may be included in a suspension and supplied to the barrier layer 120.

[0105] The liquid supplied to the recess 150 can be any type of liquid as long as it does not corrode or damage the micro-semiconductor light-emitting device 140, and can be supplied to the recess 150 by various methods (such as spraying, dripping, inkjet dot method, or a method of allowing the liquid to flow to the barrier layer 120). The liquid can include, for example, one of the group consisting of water, ethanol, alcohol, polyol, ketone, halogenated hydrocarbon, acetone, flux, and organic solvent, or a combination thereof. The organic solvent can include, for example, isopropyl alcohol (IPA). The amount of the supplied liquid can be adjusted to change so that the liquid matches the recess 150 or overflows from the recess 150.

[0106] The micro semiconductor light emitting devices 140 may be directly spread onto the barrier layer 120 without other liquid, or may be contained in a suspension and supplied onto the barrier layer 120. As a method of supplying the micro semiconductor light emitting devices 140 contained in the suspension, various methods may be used, such as a spraying method, a dispensing method of dropping liquid as droplets, an inkjet method of discharging liquid like a printing method, a method of allowing the suspension to flow to the barrier layer 120, and the like.

[0107] Figure 11 Schematically illustrates a scanning process for aligning a micro semiconductor light emitting device. Figure 11, the absorber 10 can scan the driving substrate 110. When the absorber 10 in contact with the barrier layer 120 passes through the plurality of recesses 150 according to the scanning, the micro-semiconductor light-emitting devices 140 can move into the recesses 150, and the absorber 10 can also absorb the liquid L present in the recesses 150. The absorber 10 can be any material as long as it can absorb the liquid L and its shape or structure is not limited. The absorber 10 may include, for example, fabric, tissue, polyester fiber, paper, or a wiper.

[0108] The absorber 10 can be used alone without other auxiliary devices, but is not limited thereto, and can be coupled to the support 20 to facilitate scanning of the drive substrate 110. The support 20 can have various shapes and structures suitable for scanning the drive substrate 110. For example, the support 20 can have the shape of a rod, a blade, a plate, a wiper, etc. The absorber 10 can be provided on either side of the support 20 or can surround the support 20. The shapes of the support 20 and the absorber 10 are not limited to the quadrilateral cross-sectional shape shown and can have a circular cross-sectional shape.

[0109] The absorber 10 can scan the drive substrate 110 while pressing the barrier layer 120 with an appropriate pressure. Since the barrier layer 120 includes a flexible polymer material, the barrier layer 120 can be restored to its original thickness even if pressure is applied to the barrier layer 120. Scanning can be performed according to various methods, such as sliding, rotating, translating, reciprocating, rolling, turning and / or rubbing of the absorber 10, which can include regular methods or irregular methods. Scanning can be performed by moving the drive substrate 110 instead of moving the absorber 10, or by methods such as sliding, rotating, translating, reciprocating, rolling, turning and / or rubbing the drive substrate 110. In addition, scanning can also be performed through cooperation between the absorber 10 and the drive substrate 110.

[0110] Supplying the liquid L to the recess 150 of the barrier layer 120 and supplying the micro-semiconductor light emitting device 140 to the barrier layer 120 can be performed in the reverse order of the order described above. In addition, supplying the liquid L to the recess 150 of the barrier layer 120 and supplying the micro-semiconductor light emitting device 140 to the barrier layer 120 can be performed simultaneously in one step. For example, by supplying a suspension containing the micro-semiconductor light emitting device 140 to the barrier layer 120, the liquid L and the micro-semiconductor light emitting device 140 can be supplied to the barrier layer 120 at the same time.

[0111] After the absorber 10 scans the driving substrate 110, the micro semiconductor light emitting devices 140 remaining on the barrier layer 120 but not entering the recesses 150 may be removed. Furthermore, the above process may be repeated until the micro semiconductor light emitting devices 140 are positioned in all recesses 150.

[0112] As described above, the display device according to the example embodiment can be manufactured over a large area using a fluid self-assembly method. In addition, since the display device according to the example embodiment can include a side reflection structure in the barrier layer 120 for aligning the micro-semiconductor light-emitting device 140, crosstalk between adjacent pixels can be reduced or prevented, and since the lower reflection structure 131 is provided at the bottom of the recess 150 in which the micro-semiconductor light-emitting device 140 is disposed, light efficiency can be improved.

[0113] In the above description, the shape of the recess 150 is described as being similar to the shape of the micro semiconductor light emitting device 140, but the embodiment is not limited thereto. Specifically, in order to align the micro semiconductor light emitting device 140 to an accurate position with almost no deviation, the shape of the recess 150 can be designed to be different from the shape of the micro semiconductor light emitting device 140. For example, Figure 12 is a perspective view showing an example of the shape of a recess provided in a barrier layer of a display device, Figure 13 It shows Figure 12 A plan view of the shape of the depression is shown.

[0114] Reference Figure 12 and Figure 13 Each recess 150 includes a first trapping portion 150A and a second trapping portion 150B. The first trapping portion 150A provides a space for the micro-semiconductor light-emitting device 140 to move within the recess 150. The second trapping portion 150B is connected to the first trapping portion 150A and has a shape and size that allows the micro-semiconductor light-emitting device 140 to be positioned therein. Each recess 150 may also include a third trapping portion 150C connected to the second trapping portion 150B and having a smaller size than the second trapping portion 150B. The third trapping portion 150C can serve as an impurity space. When the micro-semiconductor light-emitting device 140 is aligned within the second trapping portion 150B, impurities that may be present in the suspension containing the micro-semiconductor light-emitting device 140 can be attracted to the third trapping portion 150C, making it easier for the micro-semiconductor light-emitting device 140 to align within the second trapping portion 150B. The third trapping portion 150C is smaller than the second trapping portion 150B, and its shape is not particularly limited. The third trapping portion 150C may be provided in plurality or omitted.

[0115] The first capturing portion 150A may be sized to have a space within which the micro semiconductor light emitting device 140 can move. Furthermore, the first capturing portion 150A may be sized so that one micro semiconductor light emitting device 140 is disposed in one recess 150. For example, the first capturing portion 150A may be sized so that two or more micro semiconductor light emitting devices 140 cannot fit into one recess 150. The first capturing portion 150A partially overlaps with the circular second capturing portion 150B and may have a shape in which a portion of the circle is cut away.

[0116] The second capture portion 150B may have a shape and size corresponding to that of the micro semiconductor light-emitting device 140. For example, the second capture portion 150B may have a shape and size within which the micro semiconductor light-emitting device 140 may be positioned. The second capture portion 150B is sufficiently large to accommodate the micro semiconductor light-emitting device 140 and may have substantially the same size as the micro semiconductor light-emitting device 140. For example, the width of the second capture portion 150B may be 100% or greater and 105% or less, 103% or less, or 101% or less of the width of the micro semiconductor light-emitting device 140. Furthermore, when the micro semiconductor light-emitting device 140 is circular, the second capture portion 150B may also have a circular shape or may have an elliptical or polygonal shape into which the circular micro semiconductor light-emitting device 140 may be inserted. When the micro semiconductor light-emitting device 140 is quadrilateral, the second capture portion 150B may also have a quadrilateral shape or may have a circular, elliptical, or other polygonal shape into which the quadrilateral micro semiconductor light-emitting device 140 may be positioned.

[0117] exist Figure 10 and Figure 11 In the scanning process shown, when the absorber 10 scans the drive substrate 110 in a direction from the first capture portion 150A toward the second capture portion 150B, the micro semiconductor light emitting device 140 can be more accurately positioned in the second capture portion 150B. Since the second capture portion 150B has substantially the same size as the micro semiconductor light emitting device 140, the micro semiconductor light emitting device 140 can be aligned in an almost accurate position throughout the entire area of ​​the drive substrate 110.

[0118] 14A to 14C 1 and 2 show various shapes of recesses according to example embodiments. Figure 14A , the recess 250 may include a first capturing portion 250A, a second capturing portion 250B, and a third capturing portion 250C. The second capturing portion 250B may have a circular shape, and the first capturing portion 250A may have a shape in which one end is deformed into a square. Figure 14B, the first capture portion 350A, the second capture portion 350B, and the third capture portion 350C of the recess 350 may have a quadrangular shape, and the circular micro semiconductor light emitting device 140 may be disposed in the second capture portion 350B. Figure 14C , the first capturing portion 450A, the second capturing portion 450B, and the third capturing portion 450C of the recess 450 may have a quadrangular shape, and the quadrangular micro semiconductor light emitting device 140 may be disposed in the second capturing portion 450B.

[0119] The micro-semiconductor light emitting devices 140 are directly aligned on the driving substrate 110 using the fluid self-assembly method. However, the embodiment is not limited thereto, and the micro-semiconductor light emitting devices 140 can also be aligned on a transfer substrate using the fluid self-assembly method, and then the micro-semiconductor light emitting devices 140 on the transfer substrate are transferred to the driving substrate 110. For example, Figures 15A to 15F is a cross-sectional view illustrating a method of manufacturing a display device according to another example embodiment.

[0120] Reference Figure 15A , the lower reflective structure 231 may be first formed on the upper surface of the driving substrate 210. A plurality of lower reflective structures 231 may be formed at locations where the micro semiconductor light emitting devices 140 are to be disposed. The lower reflective structure 231 may be configured to also serve as an electrode pad. To this end, the lower reflective structure 231 may include a first reflective metal layer 231a, a second reflective metal layer 231b, and an insulating layer 231c disposed to cover the first reflective metal layer 231a and the second reflective metal layer 231b. Although in Figure 15A 2. In the embodiment, a plurality of separate insulating layers 231c are shown disposed on the drive substrate 210, but the embodiment is not limited thereto. For example, a single insulating layer 231c covering all of the plurality of first reflective metal layers 231a and the plurality of second reflective metal layers 231b may be formed on the drive substrate 210.

[0121] Reference Figure 15B , a through hole can be formed by penetrating the insulating layer 231c in the vertical direction so that a portion of the first reflective metal layer 231a and a portion of the second reflective metal layer 231b are exposed. In addition, a bump layer 220 can be formed by filling the through hole with a bump material. The bump layer 220 may include a first bump layer 220a in contact with the first reflective metal layer 231a and a second bump layer 220b in contact with the second reflective metal layer 231b. The first bump layer 220a and the second bump layer 220b may partially extend on the upper surface of the insulating layer 231c and be spaced apart from each other on the upper surface of the insulating layer 231c. Together with the bump material, the bump layer 220 may also include an under bump metal (UBM).

[0122] Reference Figure 15C, the transfer substrate 310 on which the micro-semiconductor light-emitting devices 140 are aligned can be set on the upper surface of the driving substrate 210. The transfer substrate 310 may include a plurality of recesses 315, and the micro-semiconductor light-emitting devices 140 are respectively placed in the recesses 315 using a fluid self-assembly method. Specifically, the micro-semiconductor light-emitting devices 140 can be aligned so that their first electrodes 148 and second electrodes 149 are arranged toward the outside of the recesses 315. The transfer substrate 310 can be set so that the first electrodes 148 and second electrodes 149 of the micro-semiconductor light-emitting devices 140 face the driving substrate 210. Then, the micro-semiconductor light-emitting devices 140 aligned on the transfer substrate 310 can be transferred to the driving substrate 210. Therefore, the lower reflective structure 231 is provided between each micro-semiconductor light-emitting device 140 and the driving substrate 210.

[0123] Reference Figure 15D , the first electrode 148 and second electrode 149 of the micro-semiconductor light-emitting device 140 transferred to the drive substrate 210 can respectively contact different bump layers. For example, the first electrode 148 of the micro-semiconductor light-emitting device 140 can contact the second bump layer 220b, and the second electrode 149 can contact the first bump layer 220a. Thus, the first electrode 148 of the micro-semiconductor light-emitting device 140 can be electrically connected to the second reflective metal layer 231b via the second bump layer 220b, and the second electrode 149 can be electrically connected to the first reflective metal layer 231a via the first bump layer 220a. The first reflective metal layer 231a and the second reflective metal layer 231b can each be electrically connected to the drive circuit within the drive substrate 210.

[0124] Reference Figure 15E A transparent protective layer 240 may be formed to cover the drive substrate 210 and the micro semiconductor light emitting devices 140. The protective layer 240 may also be patterned to form a groove 245 around the periphery of each micro semiconductor light emitting device 140. Figure 15E , the groove 245 is shown as completely penetrating the protective layer 240 in the vertical direction, but the embodiment is not limited thereto. When the groove 245 completely penetrates the protective layer 240, the upper surface of the drive substrate 210 may be exposed by the groove 245. According to another example embodiment, when an insulating layer 231c covering both the first reflective metal layer 231a and the second reflective metal layer 231b is formed on the drive substrate 210, the insulating layer 231c may be exposed by the groove 245. However, when the groove 245 does not completely penetrate the protective layer 240, the bottom of the groove 245 may be formed in the lower portion of the protective layer 240, and the upper surface of the drive substrate 210 or the upper surface of the insulating layer 231c may not be exposed.

[0125] Reference Figure 15F, the groove 245 can be filled with a reflective metal material to form a side reflective structure 260. The side reflective structure 260 can be provided to surround the periphery of each micro-semiconductor light-emitting device 140. The side reflective structure 260 can extend completely through the protective layer 240 from the upper surface of the protective layer 240 to the lower surface of the protective layer 240, but is not limited thereto. For example, the side reflective structure 260 may not penetrate the protective layer 240, so that the lower surface of the side reflective structure 260 is surrounded by the lower portion of the protective layer 240. The side reflective structure 260 can be provided so as not to contact the first reflective metal layer 231a or the second reflective metal layer 231b.

[0126] by Figures 15A to 15F The display device 200 manufactured in the manner shown differs from the aforementioned display device in that it does not include a barrier layer. Furthermore, the directions in which the first electrode 148 and the second electrode 149 of the micro-semiconductor light-emitting device 140 face, and the corresponding wiring structure of the display device 200 are different from those of the aforementioned display device. However, the configurations of the side-reflecting structure and the bottom-reflecting structure described above with respect to the aforementioned display device can generally be applied to the display device 200.

[0127] Figure 16 is a cross-sectional view schematically showing a structure of a display device 1000 according to another exemplary embodiment. Figure 16 The display device 1000 may further include a wavelength conversion layer 1100 disposed on the protective layer 170 and an upper substrate 1200 disposed on the wavelength conversion layer 1100. Figure 16 In the display device 1000 shown, the structure including the driving substrate 110 and the micro semiconductor light emitting device 140 disposed under the protective layer 170 may be the same as the configuration of the above-mentioned display devices 100, 100a, 100b and 200. Figure 16 In the figure, for convenience, the wiring structure of the micro semiconductor light emitting device 140 is omitted.

[0128] The wavelength conversion layer 1100 may include a first wavelength conversion layer 1100R, a second wavelength conversion layer 1100G, and a third wavelength conversion layer 1100B. The first wavelength conversion layer 1100R converts light emitted from the micro-semiconductor light-emitting device 140 into light having a first wavelength band, the second wavelength conversion layer 1100G converts light emitted from the micro-semiconductor light-emitting device 140 into light having a second wavelength band, and the third wavelength conversion layer 1100B converts light emitted from the micro-semiconductor light-emitting device 140 into light having a third wavelength band. For example, the light having the first wavelength band may be red light, the light having the second wavelength band may be green light, and the light having the third wavelength band may be blue light. The first wavelength conversion layer 1100R, the second wavelength conversion layer 1100G, and the third wavelength conversion layer 1100B may be spaced apart from each other with the barrier 1110 therebetween, and may each face its corresponding micro-semiconductor light-emitting device 140.

[0129] When the micro-semiconductor light-emitting device 140 emits blue light, the third wavelength conversion layer 1100B may include a resin that transmits blue light. The second wavelength conversion layer 1100G may convert the blue light emitted from the micro-semiconductor light-emitting device 140 to emit green light. The second wavelength conversion layer 1100G may include quantum dots or phosphors that are excited by blue light to emit green light. The first wavelength conversion layer 1100R may convert the blue light emitted from the micro-semiconductor light-emitting device 140 into red light to be emitted. The first wavelength conversion layer 1100R may include quantum dots or phosphors that are excited by blue light and emit red light.

[0130] The quantum dots included in the first wavelength conversion layer 1100R or the second wavelength conversion layer 1100G may have a core-shell structure having a core portion and a shell portion, or may have a particle structure without a shell. The core-shell structure may include a single shell structure or a multi-shell structure (e.g., a double shell structure). The quantum dots may include II-VI series semiconductors, III-V series semiconductors, IV-VI series semiconductors, IV series semiconductors, and / or graphene quantum dots. The quantum dots may include, for example, cadmium (Cd), selenium (Se), zinc (Zn), sulfur (S), and / or indium phosphide (InP), and each quantum dot may have a diameter of tens of nm or less, for example, a diameter of about 10 nm or less. The quantum dots included in the first wavelength conversion layer 1100R and the second wavelength conversion layer 1100G may have different sizes.

[0131] Figure 17 is a cross-sectional view schematically showing a structure of a display device 1000a according to another exemplary embodiment. Figure 17The display device 1000a may further include a cover layer 1300 on the wavelength conversion layer 1100 and a color filter layer 1400 on the cover layer 1300. The cover layer 1300 and the color filter layer 1400 may be provided at Figure 16 The display device 1000 is shown between the wavelength conversion layer 1100 and the upper substrate 1200. The color filter layer 1400 includes a first color filter 1400R, a second color filter 1400G, and a third color filter 1400B, which are spaced apart from each other with a black matrix 1410 therebetween. The first color filter 1400R, the second color filter 1400G, and the third color filter 1400B face the first wavelength conversion layer 1100R, the second wavelength conversion layer 1100G, and the third wavelength conversion layer 1100B, respectively. The first color filter 1400R, the second color filter 1400G, and the third color filter 1400B transmit red light, green light, and blue light, respectively, and absorb light of other colors. When the color filter layer 1400 is provided, light other than red light emitted from the first wavelength conversion layer 1100R without wavelength conversion or light other than green light emitted from the second wavelength conversion layer 1100G without wavelength conversion can be removed by the first color filter 1400R and the second color filter 1400G, respectively, thereby improving the color purity of the display device 1000a.

[0132] The above-mentioned display device can be applied to various electronic devices with screen display functions. Figure 18 is a schematic block diagram of an electronic device according to an example embodiment. Figure 18 , an electronic device 8201 may be provided in a network environment 8200. In the network environment 8200, the electronic device 8201 may communicate with another electronic device 8202 via a first network 8298 (a short-range wireless communication network, etc.), or may communicate with another electronic device 8204 and / or a server 8208 via a second network 8299 (a long-range wireless communication network, etc.). The electronic device 8201 may communicate with the electronic device 8204 via the server 8208. The electronic device 8201 may include a processor 8220, a memory 8230, an input device 8250, an audio output device 8255, a display device 8260, an audio module 8270, a sensor module 8276, an interface 8277, a haptic module 8279, a camera module 8280, a power management module 8288, a battery 8289, a communication module 8290, a user identification module 8296, and / or an antenna module 8297. Some of these components of the electronic device 8201 may be omitted, or other components may be added to the electronic device 8201. Some of these components may be implemented as an integrated circuit. For example, the sensor module 8276 (fingerprint sensor, iris sensor, illumination sensor, etc.) may be included in the display device 8260 (display, etc.).

[0133] The processor 8220 can execute software (such as program 8240) to control one or more other components (hardware, software components, etc.) connected to the processor 8220 within the electronic device 8201 and perform various data processing or operations. As part of the data processing or operations, the processor 8220 can load instructions and / or data received from other components (such as the sensor module 8276 and the communication module 8290) into the volatile memory 8232, process the instructions and / or data stored in the volatile memory 8232, and store the resulting data in the non-volatile memory 8234. The non-volatile memory 8234 may include an internal memory 8236 installed in the electronic device 8201 and a removable external memory 8238. The processor 8220 may include a main processor 8221 (central processing unit, application processor, etc.) and auxiliary processors 8223 (graphics processing unit, image signal processor, sensor hub processor, communication processor, etc.), which can operate independently or in conjunction with the main processor 8221. The auxiliary processor 8223 may use less power than the main processor 8221 and may perform specialized functions.

[0134] When the main processor 8221 is inactive (sleep state), the auxiliary processor 8223 may control functions and / or states related to some of the components of the electronic device 8201 (display device 8260, sensor module 8276, communication module 8290, etc.) instead of the main processor 8221, or when the main processor 8221 is active (application execution state), the auxiliary processor 8223 may control functions and / or states related to some of the components of the electronic device 8201 (display device 8260, sensor module 8276, communication module 8290, etc.) together with the main processor 8221. The auxiliary processor 8223 (image signal processor, communication processor, etc.) may be implemented as part of other function-related components (camera module 8280, communication module 8290, etc.).

[0135] The memory 8230 can store various data required by the components of the electronic device 8201 (processor 8220, sensor module 8276, etc.). The data may include, for example, software (program 8240, etc.) and input data and / or output data for commands related thereto. The memory 8230 may include a volatile memory 8232 and / or a non-volatile memory 8234.

[0136] The program 8240 may be stored as software in the memory 8230 and may include an operating system 8242 , middleware 8244 , and / or applications 8246 .

[0137] The input device 8250 may receive commands and / or data from outside the electronic device 8201 (a user, etc.) to be used by components (the processor 8220, etc.) of the electronic device 8201. The input device 8250 may include a remote control, a microphone, a mouse, a keyboard, and / or a digital pen (such as a stylus).

[0138] The audio output device 8255 can output audio signals to the outside of the electronic device 8201. The audio output device 8255 can include a speaker and / or a receiver. The speaker can be used for general purposes such as multimedia playback or recording playback, and the receiver can be used to answer incoming calls. The receiver can be integrated into the speaker or implemented as a separate component.

[0139] The display device 8260 can visually provide information to the outside of the electronic device 8201. The display device 8260 may include a display, a holographic device or a projector, and a control circuit for controlling the corresponding device. The display device 8260 may include a driving circuit, a micro semiconductor light-emitting device, a side reflection structure, a lower reflection structure, etc. The display device 8260 may also include a touch circuit configured to detect a touch and / or a sensor circuit (such as a pressure sensor) configured to measure the strength of the force generated by the touch.

[0140] The audio module 8270 can convert sound into an electrical signal, or vice versa, can convert an electrical signal into sound. The audio module 8270 can obtain sound through the input device 8250 and output the sound through a speaker and / or earphone directly or wirelessly connected to the audio output device 8255 and / or another electronic device (electronic device 8202, etc.) of the electronic device 8201.

[0141] The sensor module 8276 can detect the operating state (power, temperature, etc.) or external environmental state (user status, etc.) of the electronic device 8201 and generate an electrical signal and / or data value corresponding to the detected state. The sensor module 8276 can include a gesture sensor, a gyroscope sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an infrared (IR) sensor, a biometric sensor, a temperature sensor, a humidity sensor, and / or an illumination sensor.

[0142] The interface 8277 may support one or more designated protocols that can be used to connect the electronic device 8201 directly or wirelessly to another electronic device (e.g., the electronic device 8202). The interface 8277 may include a high-definition multimedia interface (HDMI), a universal serial bus (USB) interface, an SD card interface, and / or an audio interface.

[0143] The connection end 8278 may include a connector through which the electronic device 8201 can be physically connected to another electronic device (such as the electronic device 8202). The connection end 8278 may include an HDMI connector, a USB connector, an SD card connector, and / or an audio connector (such as a headphone connector).

[0144] The haptic module 8279 may convert electrical signals into mechanical stimulation (vibration, motion, etc.) or electrical stimulation that a user can recognize through tactile or kinesthetic sense. The haptic module 8279 may include a motor, a piezoelectric element, and / or an electrical stimulation device.

[0145] The camera module 8280 can capture still images and videos. The camera module 8280 may include a lens assembly (including one or more lenses), an image sensor, an image signal processor, and / or a flash. The lens assembly included in the camera module 8280 may collect light emitted from an object to be imaged.

[0146] The power management module 8288 may manage power supplied to the electronic device 8201. The power management module 8288 may be implemented as part of a power management integrated circuit (PMIC).

[0147] The battery 8289 can supply power to the components of the electronic device 8201. The battery 8289 can include a non-rechargeable primary battery, a rechargeable secondary battery, and / or a fuel cell.

[0148] The communication module 8290 can establish a direct (wired) communication channel and / or a wireless communication channel between the electronic device 8201 and other electronic devices (electronic device 8202, electronic device 8204, server 8208, etc.), and support communication through the established communication channel. The communication module 8290 may include one or more communication processors that operate independently of the processor 8220 (application processor, etc.) and support direct communication and / or wireless communication. The communication module 8290 may include a wireless communication module 8292 (cellular communication module, short-range wireless communication module, global navigation satellite system (GNSS) communication module, etc.) and / or a wired communication module 8294 (local area network (LAN) communication module, power line communication module, etc.). Among these communication modules, the corresponding communication module can communicate with another electronic device via a first network 8298 (short-range communication network, such as Bluetooth, WiFi Direct, or Infrared Data Association (IrDA)) or a second network 8299 (long-range communication network, such as a cellular network, the Internet, or a computer network (LAN), WAN, etc.). These various types of communication modules may be integrated into one component (single chip, etc.), or may be implemented as multiple components (multiple chips) separated from each other. The wireless communication module 8292 may use the user information (International Mobile Subscriber Identity (IMSI) etc.) stored in the user identification module 8296 to identify and authenticate the electronic device 8201 in a communication network (such as the first network 8298 and / or the second network 8299).

[0149] The antenna module 8297 can send signals and / or power to the outside (such as other electronic devices) or receive signals and / or power from the outside. The antenna may include a radiator including a conductive pattern formed on a board (printed circuit board (PCB) etc.). The antenna module 8297 may include one or more antennas. When multiple antennas are included, an antenna suitable for a communication method used in a communication network such as the first network 8298 and / or the second network 8299 can be selected by the communication module 8290 from the multiple antennas. Signals and / or power can be sent or received between the communication module 8290 and other electronic devices through the selected antenna. Components other than the antenna (RFIC etc.) may be included as part of the antenna module 8297.

[0150] Some of the components may be connected to each other through a communication method (bus, general purpose input and output (BPIO), serial peripheral interface (SPI), mobile industry processor interface (MIPI)) and exchange signals (commands, data, etc.) with each other.

[0151] Commands or data can be sent or received between the electronic device 8201 and the electronic device 8204 through the server 8208 connected to the second network 8299. The other electronic devices 8202 and 8204 can be devices of the same or different types as the electronic device 8201. All or part of the operations performed by the electronic device 8201 can be performed by one or more of the other electronic devices 8202, 8204 and 8208. For example, when the electronic device 8201 needs to perform a function or service, the electronic device 8201 can request one or more other electronic devices to perform part or all of the function or service instead of performing the function or service itself. Upon receiving the request, the one or more other electronic devices can perform the additional functions or services related to the request and send the execution results to the electronic device 8201. To this end, cloud computing, distributed computing and / or client-server computing technologies can be used.

[0152] Figure 19 An example of a display device according to an exemplary embodiment being applied to a mobile device 9100 is shown. The mobile device 9100 may include a display device 9110, which may include the above-described driving circuit, micro semiconductor light-emitting device, side reflective structure, lower reflective structure, etc. The display device 9110 may have a foldable structure, for example, a multi-foldable structure.

[0153] Figure 20 An example of a display device according to an exemplary embodiment being applied to a vehicle display device is shown. The display device may be a head-up display device 9200 for a vehicle and may include a display 9210 provided in an area of ​​the vehicle and an optical path changing member 9220 for changing an optical path so that a driver can see an image generated by the display 9210.

[0154] Figure 21 An example of a display device according to an exemplary embodiment being applied to augmented reality (AR) glasses 9300 or virtual reality glasses is shown. AR glasses 9300 may include a projection system 9310 that forms an image and an element 9320 that guides the image from the projection system 9310 to the user's eyes. Projection system 9310 may include the above-described drive circuit, micro semiconductor light emitting device, side reflection structure, lower reflection structure, etc.

[0155] Figure 22 An example in which the display device according to the exemplary embodiment is applied to a sign 9400 is shown. The sign 9400 can be used for outdoor advertising using a digital information display and can control advertising content, etc. through a communication network. The sign 9400 can be used, for example, by referring to Figure 18 The electronic device described is implemented.

[0156] Figure 23An example in which the display device according to the exemplary embodiment is applied to a wearable display 9500 is shown. The wearable display 9500 may include the driving circuit, micro semiconductor light emitting device, side reflection structure, lower reflection structure, etc. described above and may be configured as described above. Figure 18 The electronic device described is implemented.

[0157] The display device according to example embodiments may be applied to various products such as a rollable television (TV), a stretchable display, and the like.

[0158] It should be understood that the example embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each example embodiment should generally be considered applicable to other similar features or aspects in other embodiments. Although example embodiments have been described with reference to the accompanying drawings, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the appended claims and their equivalents.

[0159] This application claims the benefit of U.S. Provisional Application No. 63 / 156,519 filed in the U.S. Patent and Trademark Office on March 4, 2021, Korean Patent Application No. 10-2021-0071712 filed in the Korean Intellectual Property Office on June 2, 2021, and Korean Patent Application No. 10-2021-0115703 filed in the Korean Intellectual Property Office on August 31, 2021, the disclosures of which are incorporated herein by reference in their entirety.

Claims

1. A display device comprising: Driver substrate; a barrier layer, disposed on the upper surface of the driving substrate and comprising a plurality of recesses; a micro semiconductor light emitting device disposed in each of the plurality of recesses; as well as a side reflective structure disposed in the barrier layer and provided adjacent to a sidewall of each of the plurality of recesses, wherein the side reflective structure is configured to reflect light emitted from the micro semiconductor light emitting device in a lateral direction, The display device further includes a lower reflective structure having a hydrophilic surface and disposed on a bottom side of each of the plurality of recesses, wherein the lower reflective structure is configured to reflect light emitted from the micro semiconductor light emitting device in a downward direction.

2. The display device according to claim 1 , wherein the side reflective structure is arranged so that the side wall of the recess is arranged between the micro semiconductor light emitting device and the side reflective structure, and The distance from the side wall of the recess to the side reflection structure is 0.1 μm to 50 μm within the range.

3. The display device according to claim 1 , wherein the width of the side reflection structure in a direction parallel to the upper surface of the drive substrate is in the range of 1 μm to a value smaller than the width of the micro-semiconductor light-emitting device. The display device according to claim 1 , wherein the side reflection structure comprises a metal material. 5 . The display device of claim 1 , wherein the side reflection structure extends from an upper surface of the barrier layer to a lower surface of the barrier layer. 6 . The display device of claim 1 , wherein an area of ​​the low reflection structure is larger than an area of ​​each of the plurality of recesses, and a portion of the barrier layer is disposed on a portion of an upper surface of the low reflection structure. 7 . The display device of claim 6 , wherein the lower reflection structure is disposed such that the upper surface of the lower reflection structure contacts a lower surface of the side reflection structure. 8 . The display device of claim 1 , wherein the low reflection structure comprises a reflective metal layer and an insulating layer disposed on the reflective metal layer, the insulating layer having the hydrophilic surface.

9. The display device according to claim 8, wherein the thickness of the reflective metal layer in the normal direction of the upper surface of the drive substrate is between 50 nm and 1 nm. μm within the range.

10. The display device according to claim 8, wherein the reflective metal layer comprises a plurality of reflective metal layers respectively disposed under the plurality of recesses, and A single insulating layer is provided on the upper surface of the drive substrate and on the plurality of reflective metal layers.

11. The display device of claim 8, wherein the reflective metal layer comprises at least one of aluminum and silver. 12 . The display device of claim 1 , wherein the low reflection structure comprises first and second dielectric layers repeatedly and alternately stacked, the first dielectric layer having a first refractive index and the second dielectric layer having a second refractive index different from the first refractive index.

13. The display device according to claim 12, wherein the thickness of the lower reflective structure in the normal direction of the upper surface of the driving substrate is in the range of 500 nm to 2 μm within the range. 14 . The display device of claim 1 , further comprising a hydrophobic pattern disposed on an upper surface of the barrier layer and comprising the same material as that of the side reflection structure. 15 . The display device of claim 1 , wherein a lower surface of the micro semiconductor light emitting device in contact with a bottom surface of a corresponding one of the plurality of recesses has hydrophilicity. 16 . The display device of claim 15 , wherein the micro semiconductor light emitting device comprises a first electrode and a second electrode disposed on an upper surface thereof.

17. A display device as described in claim 1, wherein each of the multiple recesses includes a first capture area and a second capture area, the first capture area has a space in which the micro-semiconductor light-emitting device moves, the second capture area has a shape and size in which the micro-semiconductor light-emitting device is placed, and the second capture area is connected to the first capture area. 18 . The display device of claim 17 , wherein a size of the first capture region is set so that two or more of the micro semiconductor light emitting devices do not enter each of the plurality of recesses. 19 . The display device of claim 17 , wherein a width of the second trapping region is in a range from 100% to 105% of a width of the micro semiconductor light emitting device.

20. The display device of claim 1, further comprising a wavelength conversion layer configured to convert a wavelength of light emitted from the micro semiconductor light emitting device.

21. A display device comprising: Driver substrate; a plurality of micro semiconductor light emitting devices, arranged on the upper surface of the driving substrate; a protective layer, disposed on the upper surface of the driving substrate and the plurality of micro-semiconductor light-emitting devices; as well as a side reflective structure disposed within the protective layer and adjacent to a periphery of each of the plurality of micro-semiconductor light emitting devices, wherein the side reflective structure is configured to reflect light emitted from the micro-semiconductor light emitting device in a lateral direction, The display device further includes a lower reflection structure disposed between each of the plurality of micro-semiconductor light emitting devices and the driving substrate, and The lower reflection structure includes a reflective metal layer and an insulating layer arranged on the reflective metal layer.

22. The display device according to claim 21, wherein the width of the side reflection structure in a direction parallel to the upper surface of the drive substrate is in the range of 1 μm to a value smaller than the width of the micro-semiconductor light-emitting device.

23. The display device of claim 21, wherein the side reflection structure comprises a metal material. 24 . The display device of claim 21 , wherein the side reflection structure extends from an upper surface of the protection layer to a lower surface of the protection layer.

25. The display device of claim 21, wherein each of the plurality of micro semiconductor light emitting devices comprises a first electrode and a second electrode disposed on the same surface.

26. A display device as described in claim 25, wherein the reflective metal layer includes a first reflective metal layer electrically connected to the first electrode of each of the plurality of micro-semiconductor light-emitting devices and a second reflective metal layer electrically connected to the second electrode of each of the plurality of micro-semiconductor light-emitting devices.

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