KR-20260062637-A - light emitting device and display device using the same

Abstract

The disclosed light-emitting element comprises a light-emitting part including a plurality of sequentially stacked light-emitting structures, each having a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer. A plurality of individual electrodes are provided on the lower surface of the light-emitting part to contact the first conductivity type semiconductor layers of the plurality of light-emitting structures. At least some of the plurality of individual electrodes have a conductive via structure. A common electrode is provided on the side of the light-emitting part to contact the sides of the second conductivity type semiconductor layers of the plurality of light-emitting structures. The sides of the first conductivity type semiconductor layers and the active layers of the plurality of light-emitting structures are insulated from the common electrode by an insulating layer.

Inventors

• 오영택
• 김주성
• 박준용
• 신동철
• 한주헌
• 황경욱
• 황준식
• 송상훈
• 유민철

Assignees

• 삼성전자주식회사

Dates

Publication Date

20260507

Application Date

20241029

Claims (20)

1. A light-emitting part comprising first, second, and third light-emitting structures that are sequentially stacked to emit light of different wavelengths, wherein each of the first, second, and third light-emitting structures comprises a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer that are sequentially stacked; First, second, and third individual electrodes provided on the lower surface of the light-emitting part and respectively contacting the first conductive semiconductor layers of the first, second, and third light-emitting structures, and having at least a portion having a conductive via structure; A common electrode provided on the side of the light-emitting part and in contact with the sides of the second conductive semiconductor layers of the first, second, and third light-emitting structures; and A light-emitting device comprising: an insulating layer that insulates the sides of the first conductive semiconductor layers and the active layers of the first, second, and third light-emitting structures with respect to the common electrode.
2. In paragraph 1, The sides of the first conductive semiconductor layers and the active layers of the first, second, and third light-emitting structures are stepped inwardly inwardly from the sides of the second conductive semiconductor layers of the first, second, and third light-emitting structures.
3. In paragraph 2, A light-emitting device having a step difference of 0.5 μm or less between the sides of the first conductive semiconductor layers and the active layers of the first, second, and third light-emitting structures and the sides of the second conductive semiconductor layers of the first, second, and third light-emitting structures.
4. In paragraph 1, The above common electrode is a light-emitting element that surrounds the side of the light-emitting part.
5. In paragraph 1, The above common electrode is a light-emitting element extending to the upper surface of the light-emitting part.
6. In paragraph 1, The above common electrode is a light-emitting device comprising a transparent electrode material.
7. In paragraph 1, The first individual electrode includes a first electrode pad that contacts the lower surface of the first conductive semiconductor layer of the first light-emitting structure, and The above second and third individual electrodes are, A light-emitting element comprising a second and third electrode pad disposed on the lower surface of the light-emitting part, and second and third conductive vias that electrically connect the second and third electrode pads to the first conductive semiconductor layers of the second and third light-emitting structures, respectively.
8. In paragraph 1, Each of the first, second, and third individual electrodes comprises a first, second, and third electrode pad disposed on the lower surface of the light-emitting part, and first, second, and third conductive vias that electrically connect the first, second, and third electrode pads to the first conductive semiconductor layers of the first, second, and third light-emitting structures, respectively.
9. In paragraph 1, A reflective layer surrounding the side of the above-mentioned light-emitting part; A light-emitting device comprising a passivation layer that insulates the common electrode and the reflective layer.
10. In paragraph 1, The side of the above-mentioned light-emitting part is a light-emitting element parallel to the stacking direction of the first, second, and third light-emitting structures.
11. In paragraph 1, The side of the light-emitting part is inclined so as to gradually expand outward from the first light-emitting structure toward the third light-emitting structure.
12. In paragraph 1, A light-emitting element comprising a scattering pattern provided on the upper surface of the light-emitting part.
13. In paragraph 1, A light-emitting element comprising a lens provided on the upper surface of the light-emitting part.
14. In paragraph 1, The above third light-emitting structure is a light-emitting element that generates red light.
15. In Paragraph 14, The above first and second light-emitting structures are light-emitting elements that generate blue light and green light.
16. A light-emitting part comprising a plurality of sequentially stacked light-emitting structures, each having a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer; A plurality of individual electrodes provided on the lower surface of the light-emitting part and in contact with the first conductive semiconductor layers of the plurality of light-emitting structures, at least a portion of which has a conductive via structure; A common electrode provided on the side of the light-emitting part and in contact with the sides of the second conductivity type semiconductor layers of the plurality of light-emitting structures; A light-emitting device comprising: an insulating layer that insulates the sides of the first conductive semiconductor layers and the active layers of the plurality of light-emitting structures with respect to the common electrode.
17. In Paragraph 16, The uppermost light-emitting structure among the plurality of light-emitting structures above is a light-emitting element that generates red light.
18. In paragraph 1, A light-emitting device in which the sides of the first conductivity type semiconductor layers and the active layers of the plurality of light-emitting structures are stepped inwardly from the sides of the second conductivity type semiconductor layers of the plurality of light-emitting structures.
19. In paragraph 1, A reflective layer surrounding the side of the above-mentioned light-emitting part; A light-emitting device comprising a passivation layer that insulates the common electrode and the reflective layer.
20. A display panel comprising a plurality of light-emitting elements described in any one of claims 1 to 19, and a driving circuit for switching the plurality of light-emitting elements on and off; A display device comprising: a controller that inputs an on-off switching signal of a plurality of light-emitting elements to a driving circuit according to a video signal.

Description

Light emitting device and display device using the same The present disclosure relates to a light-emitting element and a display device equipped with the same. Light-emitting devices, such as light-emitting diodes (LEDs), are known as next-generation light sources that have advantages over conventional light sources, such as a long lifespan, low power consumption, fast response speed, and environmental friendliness, and industrial demand is increasing due to these advantages. LEDs are commonly applied and used in various products, such as lighting devices and display devices. Recently, ultra-small LEDs in the micro or nano scale are being developed, referred to as Micro LEDs. Micro LEDs are currently being applied to relatively large display devices such as televisions, and furthermore, attempts are being made to apply them to small display devices, such as those for Augmented Reality (AR) devices. Micro LEDs used in small display devices are extremely small, measuring only a few micrometers, making it difficult to secure a large light-emitting area. In particular, in Micro LEDs where RGB subpixels are arranged vertically, the light-emitting area is reduced due to the electrodes used to drive each subpixel, which can lead to a decrease in the luminous efficiency of the Micro LED. FIG. 1 is a schematic cross-sectional view of a light-emitting element according to an exemplary embodiment. Figure 2 is a schematic cross-sectional view showing the light-emitting part illustrated in Figure 1. FIG. 3 is a schematic cross-sectional view of a light-emitting element according to an exemplary embodiment. FIG. 4 is a schematic cross-sectional view of a light-emitting element according to an exemplary embodiment. FIG. 5 is a schematic cross-sectional view of a light-emitting element according to an exemplary embodiment. FIGS. 6, FIGS. 7, and FIGS. 8 show examples of planar arrangement forms of the first, second, and third individual electrodes. FIGS. 9a to 9m show an example of a method for manufacturing light-emitting elements as illustrated in FIGS. 1 and FIGS. 3. FIGS. 10a to 10l show an example of a method for manufacturing light-emitting elements as illustrated in FIGS. 4 and 5. FIG. 11 is a schematic diagram of one embodiment of a display device. FIG. 12 is a block diagram of one embodiment of an electronic device including a display. FIG. 13 illustrates an exemplary application of an electronic device, showing one embodiment of a mobile device. FIG. 14 illustrates an exemplary application of an electronic device, showing one embodiment of a head-up display device for an automobile. FIG. 15 illustrates an example of an application of an electronic device, specifically an example of augmented reality glasses or virtual reality glasses. FIG. 16 illustrates an example of a large signage as an exemplary application of an electronic device. FIG. 17 illustrates an embodiment of a wearable display as an exemplary application of an electronic device. Recently, technology for applying light-emitting elements, such as micro LEDs, to displays has advanced significantly, and televisions equipped with micro LEDs have begun to be released. Furthermore, attempts are underway to apply micro LEDs to augmented reality devices. For displays used in augmented reality devices, very small micro LED display chips (or panels) are manufactured monolithically at the wafer level without the process of transferring micro LEDs as is done for television displays. While the size of a single pixel in television displays ranges from tens to hundreds of micrometers, in small or ultra-small displays, such as those for augmented reality devices, the size of a single pixel is very small, approximately a few micrometers. To represent a color image on a display, a single pixel (color pixel) comprises RGB subpixels. The arrangement structure of RGB subpixels can be horizontal or vertical. A horizontal arrangement is a method in which RGB subpixels are arranged horizontally, while a vertical arrangement is a method in which RGB subpixels are arranged vertically. In a horizontal arrangement, each subpixel can be referred to as a micro-LED. In a vertical arrangement, the micro-LED is a monolithic RGB micro-LED in which RGB subpixels are integrated. For color pixels of a given size, the horizontal arrangement structure has a higher difficulty in the horizontal process because subpixels must be manufactured in a smaller size compared to the vertical arrangement structure. In the vertical arrangement structure, the subpixels are arranged vertically, so the difficulty in the vertical process is higher. However, in the case of the vertical arrangement structure, subpixels can be manufactured in a larger size compared to the horizontal arrangement structure, and as a result, it exhibits greater efficiency (EQE: External Quantum Efficiency) compared to the horizontal arrangement structure. When fabricating RGB micro LED chips with a vertical arrangement structure