Light-emitting element package and display device using same

Abstract

The present disclosure is applicable to a technical field related to display devices, and relates to, for example, a light-emitting element package and a display device using a light-emitting diode (LED). The light-emitting element package according to the present disclosure comprises: a support layer; a light-emitting unit positioned on the support layer and including light-emitting elements constituting unit subpixels; a connection electrode having a metal pattern shape and connected to the light-emitting elements; and a terminal unit electrically connected to the connection electrode, wherein at least one of the light-emitting elements may have a connection structure in which two or more semiconductor structures emitting light of the same color are connected in series with each other.

Description

Light-emitting element package and display device using the same

[0001] The present invention is applicable to the field of technology related to display devices, and, for example, relates to a light-emitting element package and a display device using an LED (Light Emitting Diode).

[0002] Recently, display devices with excellent characteristics such as thinness and flexibility are being developed in the field of display technology. Currently, the major commercially available displays are represented by LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diodes).

[0003] Meanwhile, light-emitting diodes (LEDs) are semiconductor light-emitting devices well known for converting electric current into light. Starting with the commercialization of red LEDs using GaAsP compound semiconductors in 1962, they have been used as light sources for display images in electronic devices, including information and communication equipment, along with green LEDs of the GaP:N series.

[0004] Recently, these light-emitting diodes (LEDs) have been gradually miniaturized and manufactured into micrometer-sized LEDs, which are being used as pixels in display devices.

[0005] Compared to other display devices / panels, such LED technology exhibits characteristics of low power consumption, high brightness, and high reliability, and can also be applied to flexible devices. Consequently, it has recently been actively researched by research institutions and companies.

[0006] Various markets for LED displays are expanding through applications that leverage the high brightness and high reliability characteristics of LEDs. The field leading the market most significantly due to these characteristics is signage displays.

[0007] In such displays, LEDs can be manufactured in a package form that can be used as unit pixels.

[0008] In light-emitting devices, particularly LED-based display devices, the proportion of power lost in the margin voltage and current path required for driving is relatively large compared to the total power consumed by the light source, due to the low-voltage / high-current structure inherent to LEDs.

[0009] When an LED voltage higher than the margin-considered driving voltage (Vled) is set, the margin voltage is lost as heat through various paths, and most of the energy may be generated within the driving element. In such cases, efficiency degradation due to power consumption may occur, and thermal management issues arise.

[0010] Therefore, measures to resolve these problems are required.

[0011] The present disclosure aims to provide a light-emitting device package capable of reducing the driving margin voltage and a display device using the same.

[0012] In addition, we aim to provide a light-emitting element package that can reduce heat generation caused by a driving element, and a display device using the same.

[0013] In addition, we aim to provide a light-emitting device package that allows for flexibility in the design of wiring width on a wiring board, and a display device using the same.

[0014] Furthermore, according to other embodiments of the present invention, those skilled in the art will understand from the entire context of the specification and drawings that there may be additional technical problems not mentioned herein.

[0015] As an embodiment of the present disclosure, a light-emitting element package comprises: a support layer; a light-emitting portion including light-emitting elements located on the support layer and forming a unit subpixel; a connecting electrode having a metal pattern shape connected to the light-emitting elements; and a terminal portion electrically connected to the connecting electrode, wherein at least one of the light-emitting elements may have a connecting structure in which two or more semiconductor structures emitting light of the same color are connected in series.

[0016] As an embodiment of the present disclosure, the display device comprises a light-emitting element package defining an individual pixel, wherein the light-emitting element package comprises: a support layer; a light-emitting portion including light-emitting elements located on the support layer and forming a unit subpixel; a connecting electrode having a metal pattern shape connected to the light-emitting elements; and a terminal portion electrically connected to the connecting electrode, wherein at least one of the light-emitting elements may have a connecting structure in which two or more semiconductor structures emitting light of the same color are connected in series.

[0017] As an embodiment of the present disclosure, a display device comprises: a wiring substrate; a wiring electrode defining a plurality of unit subpixel regions constituting a unit pixel region on the wiring substrate; and light-emitting elements electrically connected to the wiring electrode and disposed in the unit pixel region, wherein at least one of the light-emitting elements may have a connection structure in which two or more semiconductor structures emitting light of the same color are connected in series with each other.

[0018] According to one embodiment of the present invention, the following effects are achieved.

[0019] First, according to the embodiments of the present disclosure, the overall efficiency can be increased by more than 20% because the loss due to margin voltage is reduced by half. Accordingly, the heat generated by the driving element can be reduced by about half.

[0020] In addition, the brightness doubles when driven with the same current, which can be advantageous for achieving high brightness.

[0021] The capacitor capacity can be reduced to 1 / 4, which can reduce the signal rising time, thereby increasing low-gradation expression capability and securing driving time.

[0022] In addition, low-current driving facilitates an increase in scan lines, allowing more light sources to be driven with a driver IC having the same driving current capability. Consequently, the overall manufacturing cost of the display can be reduced.

[0023] Meanwhile, there may be room in the design of the wiring width on the wiring board.

[0024] Furthermore, according to another embodiment of the present invention, there are additional technical effects not mentioned herein. Those skilled in the art will understand this from the full context of the specification and drawings.

[0025] FIG. 1 is a plan view showing a light-emitting element package according to a first embodiment of the present disclosure.

[0026] FIGS. 2 to 4 are plan views showing variations of a light-emitting element package according to a first embodiment of the present disclosure.

[0027] FIG. 5 is a cross-sectional view showing a light-emitting element of a general structure that can be used in a light-emitting element package according to embodiments of the present disclosure.

[0028] Figure 6 is a plan view of Figure 5.

[0029] FIG. 7 is a cross-sectional view showing a light-emitting element of a COB structure that can be used in a light-emitting element package according to embodiments of the present disclosure.

[0030] Figure 8 is a plan view of Figure 7.

[0031] FIG. 9 is a cross-sectional view showing a tandem light-emitting element that can be used in a light-emitting element package according to embodiments of the present disclosure.

[0032] Figure 10 is a cross-sectional view showing the detailed stacked structure of Figure 9.

[0033] FIGS. 11 and 12 are graphs showing the efficiency of a tandem structured light-emitting element that can be used in a light-emitting element package according to embodiments of the present disclosure.

[0034] FIGS. 13 to 15 are circuit diagrams showing examples of connection structures of light-emitting elements of a display device according to embodiments of the present disclosure.

[0035] FIGS. 16 and 17 are schematic diagrams for explaining the effects of using serially connected light-emitting elements according to embodiments of the present disclosure.

[0036] FIG. 18 is a plan view showing a display device according to a first embodiment.

[0037] Fig. 19 is a partial cross-sectional view of Fig. 18.

[0038] FIG. 20 is a plan view showing a display device according to a second embodiment.

[0039] Figure 21 is a partial cross-sectional view of Figure 20.

[0040] FIG. 22 is a plan view showing a display device according to a third embodiment.

[0041] Fig. 23 is a partial cross-sectional view of Fig. 22.

[0042] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Identical or similar components, regardless of drawing symbols, are assigned the same reference number, and redundant descriptions thereof will be omitted. The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably solely for the ease of drafting the specification and do not inherently possess distinct meanings or roles. Furthermore, when describing the embodiments disclosed in this specification, detailed descriptions of related prior art are omitted if it is determined that such detailed descriptions could obscure the essence of the embodiments disclosed in this specification. Additionally, it should be noted that the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification and should not be interpreted as limiting the technical concept disclosed in this specification.

[0043] Furthermore, for the convenience of explanation, each drawing is described, but it is also within the scope of the present invention that a person skilled in the art combines at least two drawings to implement other embodiments.

[0044] Furthermore, when elements such as layers, regions, or substrates are referred to as existing "on" other components, it can be understood that this means they exist directly on the other elements or that there may be an intermediate element between them.

[0045] The semiconductor light-emitting device mentioned in this specification is a concept that includes LEDs, micro LEDs, etc., and may be used interchangeably.

[0046]

[0047] FIG. 1 is a plan view showing a light-emitting element package according to a first embodiment of the present disclosure. FIG. 2 to 4 are plan views showing variations of a light-emitting element package according to a first embodiment of the present disclosure.

[0048] Referring to FIG. 1, a light-emitting device package (200) of the bottom emission type, in which light is emitted in a downward direction, is shown.

[0049] A light-emitting element package (200) according to the first embodiment may be provided with a light-emitting part (260) comprising light-emitting elements (261, 262, 263) forming a unit subpixel on a support layer (230) defining a unit package area.

[0050] The support layer (230) can form a light-emitting surface. For example, light emitted from the light-emitting part (260) can be emitted through the support layer (230). Therefore, the support layer (230) can form a light-transmitting layer.

[0051] This support layer (230) can be formed from at least one of acrylic, epoxy, silicone, Teflon, silicone acrylic, and silicone epoxy composite materials.

[0052] For example, the support layer (230) forms a substrate, and a light-emitting part (260) including light-emitting elements (261, 262, 263) may be provided on such a substrate. Hereinafter, the support layer (230) and the substrate (230) will be described interchangeably.

[0053] On the support layer (230), connecting electrodes (271, 272, 273, 274) that are electrically connected to each of the light-emitting elements (261, 262, 263; 260) may be provided. These connecting electrodes (271, 272, 273, 274) may be made of a metal with excellent reflectivity.

[0054] The light-emitting element (260) may include a first light-emitting element (261), a second light-emitting element (262), and a third light-emitting element (263). For example, the first light-emitting element (261) may be a red light-emitting element (R), the second light-emitting element (262) may be a green light-emitting element (G), and the third light-emitting element (263) may be a blue light-emitting element (B). In some cases, at least one of the first light-emitting element (261), the second light-emitting element (262), and the third light-emitting element (263) may include two or more light-emitting elements. This will be described in detail later.

[0055] When the light-emitting element package (200) is used in a display device, each of the first light-emitting element (261), the second light-emitting element (262), and the third light-emitting element (263) may correspond to an individual subpixel. The first light-emitting element (261), the second light-emitting element (262), and the third light-emitting element (263) may together form a unit pixel.

[0056] The light-emitting element (261, 262, 263) may be a mini LED having a size in millimeters or a micro LED having a size in micrometers.

[0057] The connecting electrode may include a first connecting electrode (271) connected to one side electrode of the first light-emitting element (261), a second connecting electrode (272) connected to one side electrode of the second light-emitting element (262), a third connecting electrode (273) connected to one side electrode of the third light-emitting element (263), and a fourth connecting electrode (274) commonly connected to the other side electrodes of the first light-emitting element (261), the second light-emitting element (262), and the third light-emitting element (263).

[0058] At least a portion of the connecting electrodes (271, 272, 273, 274) may be insulated by an insulating layer (not shown).

[0059] A terminal portion (211, 212, 213, 214) may be provided on each of these connecting electrodes (271, 272, 273, 274). For example, the terminal portion (211, 212, 213, 214) may be located on a portion of the connecting electrode (271, 272, 273, 274) that is not covered by an insulating layer.

[0060] In this way, the surface where the light-emitting part (260), the connecting electrode (271, 272, 273, 274), and the terminal part (211, 212, 213, 214) are located can be partially covered and flattened by an insulating layer. At this time, the terminal part (211, 212, 213, 214) can be exposed to the outside.

[0061] Meanwhile, as an exemplary embodiment, filler particles that scatter light emitted from light-emitting elements (261, 262, 263; 260) may be dispersed and located inside the support layer (230) or at a position close to the light-emitting part (260).

[0062] For example, a light-emitting element package (200) according to the first embodiment may include a support layer (230), a light-emitting part (260) including light-emitting elements (261, 262, 263) located on the support layer (230) and forming a unit subpixel, a connecting electrode (271, 272, 273, 274) having a metal pattern shape connected to the light-emitting elements (261, 262, 263), and a terminal part (211, 212, 213, 214) electrically connected to the connecting electrode (271, 272, 273, 274).

[0063] At this time, at least one of the light-emitting elements (261, 262, 263) may have a connection structure in which two or more semiconductor structures emitting light of the same color are connected in series with each other.

[0064] The refractive index of the filler particles included in the support layer (230) may be 1.3 or higher. For example, these filler particles may include a number of particles having a size in the nanometer (nm) or micrometer (㎛) range.

[0065] For example, the filler particles may include at least one of TiO2, ZnO2, ZrO2, MgF2, SnO2, ITO, SiNx, Silica, and PMMA.

[0066] The filler particles can be used for at least one of the purposes of improving the viewing angle to prevent color temperature deviation according to the light emission angle of the light-emitting part (260) and improving the reflectance.

[0067] At least one of the support layer (230) and the insulating layer may include a transparent insulating layer. For example, at least one of the support layer (230) and the insulating layer may be formed from at least one material among acrylic, epoxy, silicone, Teflon, silicone acrylic, and silicone epoxy composite. For example, the support layer (230) may be provided with filler particles dispersed using such a material as a binder.

[0068] For example, the refractive index of the transparent insulating layer forming at least one of the support layer (230) and the insulating layer may be 1.5 or less. Additionally, the refractive index of any one of the filler particles may be 1.6 or more. For example, the filler particles may include at least one of TiO2, ZnO2, and ZrO2.

[0069] At least one of these connection electrodes (271, 272, 273, 274) can be fabricated using a redistribution layer (RDL) process used in semiconductor packaging processes. Using such a redistribution layer (RDL) process, light-emitting elements (260) can be connected to the connection electrodes (271, 272, 273, 274).

[0070] For example, the connecting electrodes (271, 272, 273, 274) may be connected by direct contact with the terminal portions (211, 212, 213, 214). Meanwhile, as another example, the connecting electrodes (271, 272, 273, 274) may be connected to each other by the terminal portions (211, 212, 213, 214) and a through-connecting portion (not shown). That is, such through-connecting portions can connect the connecting electrodes (271, 272, 273, 274) and the terminal portions (211, 212, 213, 214) to each other.

[0071] Although not illustrated, in some cases, the light-emitting element package (200) may further be provided with a driving element for driving light-emitting elements (261, 262, 263; 260). The driving element may be a micro-driver integrated circuit chip (Driver IC) capable of selectively driving the light-emitting elements (260). In this case, the driving element may be connected to at least one of the light-emitting elements (261, 262, 263) and the connecting electrodes (271, 272, 273, 274). A detailed description thereof is omitted.

[0072] Referring to FIG. 1, at least one of the light-emitting elements (261, 262, 263) forming the light-emitting part (260) may have a connection structure in which two or more semiconductor structures emitting light of the same color are connected in series with each other.

[0073] This connection structure may include a first light-emitting part and a second light-emitting part connected in series on the same substrate.

[0074] For example, the first light-emitting part and the second light-emitting part may have a chip-on-board (COB) structure in which they are spaced apart from each other on a substrate (see FIG. 7 and FIG. 8). Such a COB structure will be described in detail later.

[0075] As another example, the first light-emitting part and the second light-emitting part may have a tandem structure in which they are stacked on the same substrate (see FIG. 9 and FIG. 10). This tandem structure will be described in detail later.

[0076] Referring to FIG. 1, in the light-emitting element package (200) according to the first embodiment, the first light-emitting element (261) may have a tandem structure in which the first light-emitting part and the second light-emitting part are stacked on the same substrate. That is, the first light-emitting element (261) may have a structure in which two light-emitting parts are connected in series with each other. Meanwhile, the second light-emitting element (262) and the third light-emitting element (263) may have a general light-emitting element structure.

[0077] Referring to FIG. 2, in the light-emitting element package (201) according to the first modified example, the first light-emitting element (261), the second light-emitting element (262), and the third light-emitting element (263) may have a chip-on-board (COB) structure in which the first light-emitting part and the second light-emitting part are spaced apart from each other on a substrate. That is, all of the light-emitting elements (261, 262, 263) may have a structure in which two light-emitting parts are connected in series with each other.

[0078] Referring to FIG. 3, in the light-emitting element package (202) according to the second modified example, the first light-emitting element (261) may have a chip-on-board (COB) structure in which the first light-emitting part and the second light-emitting part are spaced apart from each other on a substrate. That is, the first light-emitting element (261) may have a structure in which two light-emitting parts are connected in series with each other. Meanwhile, the second light-emitting element (262) and the third light-emitting element (263) may have a general light-emitting element structure.

[0079] Referring to FIG. 4, in the light-emitting element package (203) according to the third variant, the first light-emitting element (261) may have a tandem structure in which the first light-emitting part and the second light-emitting part are stacked on the same substrate. Meanwhile, the second light-emitting element (262) and the third light-emitting element (263) may have a chip-on-board (COB) structure in which the first light-emitting part and the second light-emitting part are spaced apart from each other on the substrate. That is, all light-emitting elements (261, 262, 263) may have a structure in which two light-emitting parts are connected in series with each other.

[0080]

[0081] FIG. 5 is a cross-sectional view showing a light-emitting element of a general structure that can be used in a light-emitting element package according to embodiments of the present disclosure. FIG. 6 is a plan view of FIG. 5.

[0082] FIG. 7 is a cross-sectional view showing a light-emitting element with a COB structure that can be used in a light-emitting element package according to embodiments of the present disclosure. FIG. 8 is a plan view of FIG. 7.

[0083] Referring to FIGS. 5 and 6, a general light-emitting element structure is illustrated. As an example of one embodiment, a light-emitting element (262, 263) of this structure may be used in a light-emitting element package (200) according to a first embodiment and a light-emitting element package (202) according to a second modified example.

[0084] A light-emitting element (262, 263) such as this may be provided with a semiconductor layer (2622) located on a base substrate (2621), a first type electrode (2623) in contact with one side of the semiconductor layer (2622), and a second type electrode (2624) in contact with the other side of the semiconductor layer (2622).

[0085] The semiconductor layer (2622) may include a first conductive (e.g., n-type) semiconductor layer, a second conductive (e.g., p-type) semiconductor layer, and an active layer located between them. A first type electrode (2623) may be in contact with the first conductive semiconductor layer, and a second type electrode (2624) may be in contact with the second conductive semiconductor layer. Meanwhile, a passivation layer (2625) for protecting the semiconductor layer (2622) may be additionally provided.

[0086] Meanwhile, referring to FIGS. 7 and 8, a light-emitting element with a COB structure is illustrated. As an example of one embodiment, such a light-emitting element (264, 265, 266) with a COB structure may be used in a light-emitting element package (201) according to a first modified example and a light-emitting element package (203) according to a third modified example.

[0087] In such a light-emitting element (264, 265, 266), a semiconductor layer (2642, 2643) divided into two parts may be located on a base substrate (2641). The parts defined by the semiconductor layer (2642, 2643) divided into two parts on such a base substrate (2641) may be referred to as a first light-emitting part (264a) and a second light-emitting part (264b), respectively. In such a chip-on-board (COB) structure, the first light-emitting part (264a) and the second light-emitting part (264b) may have a structure in which they are spaced apart from each other on the substrate (2641; base substrate).

[0088] Each of the semiconductor layers (2642, 2643) corresponding to the first light-emitting part (264a) and the second light-emitting part (264b) may include a first conductive (e.g., n-type) semiconductor layer, a second conductive (e.g., p-type) semiconductor layer, and an active layer located between them.

[0089] Additionally, each of the first semiconductor part (2642) and the second semiconductor part (2643) may have a pair of connecting electrodes. For example, the first semiconductor part (2642) may be connected to a first-1 type electrode (2644) and a first-2 type electrode (2645). Additionally, the second semiconductor part (2643) may be connected to a second-1 type electrode (2646) and a second-2 type electrode (2647). At this time, a series electrode (2648) connecting the first-2 type electrode (2645) and the second-1 type electrode (2646) may be provided on the substrate (2641). For example, the first semiconductor part (2642) and the second semiconductor part (2643) may have a structure connected in series by being connected to each other by the series electrode (2648).

[0090] Meanwhile, a passivation layer (2649) for protecting each of the first semiconductor part (2642) and the second semiconductor part (2643) may be additionally provided.

[0091] Accordingly, when light-emitting elements (264, 265, 266) are provided in a package by the first-1 type electrode (2644) and the second-2 type electrode (2647), two light-emitting parts, namely the first light-emitting part (264a) and the second light-emitting part (264b), can be connected in series with each other.

[0092]

[0093] FIG. 9 is a cross-sectional view showing a tandem structure light-emitting element that can be used in a light-emitting element package according to embodiments of the present disclosure. FIG. 10 is a cross-sectional view showing the detailed stacked structure of FIG. 9.

[0094] Referring to FIGS. 9 and 10, a light-emitting element with a tandem structure is illustrated. As an example of one embodiment, such a light-emitting element (261) with a tandem structure may be used in a light-emitting element package (200) according to a first embodiment and a light-emitting element package (203) according to a third modified embodiment.

[0095] A light-emitting element (261) of this type may have two portions of semiconductor layers (2612, 2613) vertically stacked on a base substrate (2611; substrate). The portions defined by the semiconductor layers (2612, 2613) that are continuously located in two portions on a single base substrate (2611) may be referred to as the first light-emitting portion (2612) and the second light-emitting portion (2613), respectively. In such a tandem structure, the first light-emitting portion (2612) and the second light-emitting portion (2613) may have a structure in which they are stacked together on the substrate (2611; base substrate). This tandem structure may also be referred to as a stacked structure.

[0096] Each of the first light-emitting part (2612) and the second light-emitting part (2613) may include a first conductive (e.g., n-type; n-clad) semiconductor layer, a second conductive (e.g., p-type; p-clad) semiconductor layer, and an active layer (MQW) located between them. An additional semiconductor layer (GaP; 2618) may be further provided on the second conductive semiconductor layer (p-clad).

[0097] Meanwhile, referring to FIG. 10, a highly doped semiconductor layer (2617) is positioned between the first light-emitting part (2612) and the second light-emitting part (2613) to connect the first light-emitting part (2612) and the second light-emitting part (2613) to each other. This highly doped semiconductor layer (2617) may have p++ or n++ conductivity. For example, the first light-emitting part (2612) and the second light-emitting part (2613) may have a serially connected structure by being connected to each other by the highly doped semiconductor layer (2617).

[0098] These first light-emitting part (2612) and second light-emitting part (2613) form a single semiconductor layer, and a first type electrode (2614) can be connected to one side of the first light-emitting part (2612), and a second type electrode (2615) can be connected to the other side of the second light-emitting part (2613). For example, the first type electrode (2614) can be connected to the n-type semiconductor layer of the first light-emitting part (2612), and the second type electrode (2615) can be connected to the p-type semiconductor layer of the second light-emitting part (2613).

[0099] Meanwhile, a passivation layer (2616) for protecting each of the first light-emitting part (2612) and the second light-emitting part (2613) may be additionally provided.

[0100] Accordingly, when the light-emitting element (261) is provided in the package by the first type electrode (2614) and the second type electrode (2615), two light-emitting parts, namely the first light-emitting part (2612; D2) and the second light-emitting part (2613; D1), can be connected in series with each other.

[0101] This tandem structured light-emitting element (261) can be used in a red light-emitting element.

[0102]

[0103] FIGS. 11 and 12 are graphs showing the efficiency of a tandem structured light-emitting element that can be used in a light-emitting element package according to embodiments of the present disclosure.

[0104] Figure 11 shows the external quantum efficiency as an exemplary embodiment in which a semiconductor layer is provided on a GaAs substrate, an AuGe / Au electrode is used as the n-type electrode, and an ITO electrode is used as the p-type electrode. Figure 12 shows the current flow (IV curve) as a function of voltage in the same case.

[0105] Referring to FIGS. 11 and 12, compared to a general structure (single), the tandem structure exhibits substantially twice the efficiency / flow with respect to external quantum efficiency and IV curves. As such, the light-emitting device of the tandem structure can exhibit substantially twice the efficiency for the same applied current. In addition, twice the current flows through the light-emitting device of the tandem structure with respect to the driving voltage. In other words, the light-emitting device of the tandem structure can effectively form a state in which two light-emitting devices are connected in series.

[0106]

[0107] FIGS. 13 to 15 are circuit diagrams showing examples of connection structures of light-emitting elements of a display device according to embodiments of the present disclosure.

[0108] FIGS. 13 to 15 show circuit diagrams of a display device implemented using a light-emitting element package according to the first embodiment described above.

[0109] Referring to FIG. 13, an example of a display device is shown in which a red light-emitting element (R) is connected in series, for instance, a light-emitting element package (200) according to the first embodiment is used.

[0110] Referring to FIG. 14, a case is shown in which a red light-emitting element (R), a green light-emitting element (G), and a blue light-emitting element (B) are all connected in series. For example, FIG. 14 shows an example of a display device in which a light-emitting element package (201) according to a first modified example or a light-emitting element package (203) according to a third modified example is used.

[0111] Meanwhile, as illustrated in FIG. 15, a display device can be implemented with three light-emitting elements connected in series. For example, a red light-emitting element (R) can be used with three light-emitting parts connected in series. As another example, a display device can be implemented using one series-connected light-emitting element and one general light-emitting element for the red light-emitting element (R).

[0112]

[0113] FIGS. 16 and 17 are schematic diagrams for explaining the effects of using serially connected light-emitting elements according to embodiments of the present disclosure.

[0114] In light-emitting devices, particularly LED-based display devices, the proportion of power lost in the margin voltage and current path required for driving is relatively large compared to the total power consumed by the light source, due to the low-voltage / high-current structure inherent to LEDs.

[0115] When an LED voltage higher than the margin-considered driving voltage (Vled) is set, the margin voltage is lost as heat through the following paths, and most of the energy may be generated within the driving element. In such cases, thermal management issues arise.

[0116] (1) Loss due to scan / data switching resistance of the driving element

[0117] (2) Losses occurring on the wiring of the printed circuit board (PCB)

[0118] (3) In addition, losses due to the resistance component generated by the constant current source of the driving element

[0119] When the voltage is increased by serializing light sources, the proportion of the margin voltage in the total driving voltage decreases, thereby increasing the overall efficiency of the display. In this case, since arranging two individual light sources in series on a printed circuit board (PCB) incurs high costs, serialization can be accommodated by using a COB-type light-emitting element or a tandem-structured light-emitting element as described above.

[0120] In this way, the voltage can be increased by dividing the light-emitting element within the substrate, and especially in the case of a red light-emitting element, a tandem form is possible, so serialization can be implemented with a smaller area compared to the existing one by applying a tandem structure.

[0121] Referring to Fig. 16, the advantages of using a series-connected light-emitting element structure (2-stack) are schematically shown compared to using a single light-emitting element (1-stack).

[0122] As illustrated, when using a single light-emitting element (1-stack), power consumption occurs in the current source (P=V×I=(VLED-CH)×I), the light-emitting element (LED; Vf×I), and the resistor.

[0123] Meanwhile, when using a series-connected light-emitting element (2-stack), power consumption occurs in the current source (P=V×0.5I=(VLED-CH)×0.5I), the light-emitting element (LED; 2×Vf×0.5I = Vf×I), and the resistor (0.5V×0.5I).

[0124] As such, when using light-emitting elements in a series connection structure (2-stack) as in the embodiments of the present disclosure, it can be seen that the driving voltage at the current source is the same and the current is reduced by half. Meanwhile, the power consumption at the light-emitting element is equivalent. This is because the driving voltage is doubled and the current is reduced by half. The power consumption according to the scan consumed by the resistor can be reduced.

[0125] According to the embodiments of the present disclosure, with reference to FIG. 17, it can be seen that the power consumed by the light source is the same, but the power consumed by the driving element (IC) is reduced by half.

[0126] Meanwhile, there may be room in the design of the wiring width on the wiring board.

[0127] As explained above, since the loss due to margin voltage is reduced by half, the overall efficiency can be increased by more than 20%. Accordingly, the heat generated by the driving element can be reduced by about half.

[0128] Meanwhile, as the current decreases and the voltage increases, the DC-DC conversion efficiency can increase.

[0129] In addition, the brightness doubles when driven with the same current, which can be advantageous for achieving high brightness.

[0130] The capacitor capacity can be reduced to 1 / 4, which can reduce the signal rising time, thereby increasing low-gradation expression capability and securing driving time.

[0131] Meanwhile, low-current driving facilitates an increase in scan lines, making it possible to drive more light sources with a driver IC having the same driving current capability. As a result, the overall manufacturing cost of the display can be reduced.

[0132]

[0133] FIG. 18 is a plan view showing a display device according to a first embodiment. FIG. 19 is a partial cross-sectional view of FIG. 18.

[0134] Referring to FIG. 18, the display device (10) according to the first embodiment may have wiring electrodes (121, 122, 123) defining unit subpixel areas arranged on the substrate (110) of the wiring substrate (100).

[0135] Two different light-emitting elements that emit light of the same color can be connected in series on such electrodes (121, 122, 123) to form a subpixel.

[0136] For example, in FIG. 18, a red light-emitting element (267), a green light-emitting element (262), and a blue light-emitting element (263) can all be used as light-emitting elements having a general structure as subpixels.

[0137] Accordingly, for example, in the case of a red light-emitting element (267), the wiring electrode may include a first electrode (121) connected to one light-emitting element (267), a second electrode (122) connecting two light-emitting elements (267) to each other, and a third electrode (123) connected to the other light-emitting element (267).

[0138] FIG. 19 schematically shows a structure in which one-sided light-emitting elements (267, 262, 263) are connected to electrodes (121, 122).

[0139]

[0140] FIG. 20 is a plan view showing a display device according to a second embodiment. FIG. 21 is a partial cross-sectional view of FIG. 20.

[0141] Referring to FIG. 20, the display device (10) according to the second embodiment may have wiring electrodes (121, 123) defining unit subpixel areas arranged on the substrate (110) of the wiring substrate (100).

[0142] Light-emitting elements (264, 265, 266) having a series connection structure with the COB structure described above can be used as subpixels on such electrodes (121, 123).

[0143] For example, in FIG. 20, a series connection structure can be implemented in which the red light-emitting element (264), the green light-emitting element (265), and the blue light-emitting element (266) all have a COB structure.

[0144] Accordingly, a first semiconductor part (2642) can be connected to the first electrode (121) by solder (130), and a second semiconductor part (2643) can be connected to the third electrode (123) by solder (130).

[0145] In this way, a light-emitting element (264, 265, 266) having a structure connected in series on two electrodes (121, 123) can be installed.

[0146] FIG. 21 schematically shows a structure in which a light-emitting element (264, 265, 266) having such a COB structure is connected to an electrode (121, 123).

[0147]

[0148] FIG. 22 is a plan view showing a display device according to a third embodiment. FIG. 23 is a partial cross-sectional view of FIG. 22.

[0149] Referring to FIG. 22, the display device (10) according to the third embodiment may have wiring electrodes (121, 123) defining unit subpixel areas arranged on the substrate (110) of the wiring substrate (100).

[0150] On such electrodes (121, 123), a red light-emitting element (261) having a series connection structure having the tandem structure described above and a light-emitting element (265, 266) having a COB structure can be used as subpixels.

[0151] For example, in FIG. 22, a series connection structure can be implemented in which the red light-emitting element (261) has a tandem structure, and the green light-emitting element (265) and the blue light-emitting element (266) have a COB structure.

[0152] Accordingly, for example, in the case of a red light-emitting element (261), a first light-emitting part (2612) can be connected to a first electrode (121) by solder (130) and can be connected to a third electrode (123) by solder (130).

[0153] Although not separately illustrated here, the green light-emitting element (265) and the blue light-emitting element (266) may have a first semiconductor part (2642) connected to the first electrode (121) by solder (130) as described above, and a second semiconductor part (2643) connected to the third electrode (123) by solder (130).

[0154] In this way, a light-emitting element (261, 265, 266) having a structure connected in series on two electrodes (121, 123) can be installed.

[0155] FIG. 22 schematically shows a structure in which a light-emitting element (261) having such a tandem structure is connected to electrodes (121, 123).

[0156]

[0157] The above description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention.

[0158] Accordingly, the embodiments disclosed in this invention are intended to explain, not limit, the technical concept of the invention, and the scope of the technical concept of the invention is not limited by these embodiments.

[0159] The scope of protection of the present invention shall be interpreted by the claims below, and all technical ideas within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention.

[0160] According to the present invention, a light-emitting element package using a light-emitting element and a display device using the same can be provided.

Claims

1. Support layer; A light-emitting part comprising light-emitting elements located on the above support layer and forming a unit subpixel; A connecting electrode having a metal pattern shape connected to the above light-emitting elements; and It includes a terminal portion electrically connected to the above-mentioned connecting electrode, and At least one of the above light-emitting elements is A semiconductor structure having two or more structures emitting light of the same color connected in series. Light-emitting element package.

2. In paragraph 1, the above connection structure is A first light-emitting part and a second light-emitting part connected in series on the same substrate Light-emitting element package.

3. In paragraph 2, the first light-emitting part and the second light-emitting part have a chip-on-board (COB) structure positioned spaced apart from each other on the substrate. Light-emitting element package.

4. In paragraph 2, the first light-emitting part and the second light-emitting part have a tandem structure in which they are stacked and positioned on the substrate. Light-emitting element package.

5. In paragraph 2, at least one of the light-emitting elements has a chip-on-board (COB) structure positioned spaced apart from each other on the substrate, and at least one of the remaining light-emitting elements has a tandem structure positioned stacked together on the substrate. Light-emitting element package.

6. In paragraph 5, the light-emitting element having the tandem structure is a red light-emitting element. Light-emitting element package.

7. A display device comprising a light-emitting element package defining individual pixels, The above light-emitting device package is, Support base; A light-emitting part comprising light-emitting elements located on the above support layer and forming a unit subpixel; A connecting electrode having a metal pattern shape connected to the above light-emitting elements; and It includes a terminal portion electrically connected to the above-mentioned connecting electrode, and At least one of the above light-emitting elements is A semiconductor structure having two or more structures emitting light of the same color connected in series. Display device.

8. In Clause 7, the above-mentioned connection structure is A first light-emitting part and a second light-emitting part connected in series on the same substrate Display device.

9. Wiring board; Wiring electrodes defining a plurality of unit subpixel regions constituting a unit pixel region on the wiring substrate; and It includes light-emitting elements electrically connected to the above wiring electrodes and disposed in a unit pixel area, and At least one of the above light-emitting elements is A semiconductor structure having two or more structures emitting light of the same color connected in series. Display device.

10. In Clause 9, the above-mentioned connection structure is A first light-emitting part and a second light-emitting part connected in series on the same substrate Display device.

11. In Clause 10, the above-mentioned connection structure is Two different light-emitting elements emitting the same color are connected in series Display device.

12. In claim 10, the first light-emitting part and the second light-emitting part have a chip-on-board (COB) structure positioned spaced apart from each other on the substrate. Display device.

13. In claim 10, the first light-emitting part and the second light-emitting part have a tandem structure in which they are stacked and positioned on the substrate. Display device.

14. In claim 10, at least one of the light-emitting elements has a COB structure and at least one of the remainder of the light-emitting elements has a tandem structure Display device.

15. In claim 14, the light-emitting element having the tandem structure is a red light-emitting element. Display device.

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