KR-102962834-B1 - STRETCHABLE ELECTRONIC DEVICE AND MANUFACTURING METHOD THEREOF

Abstract

The present application relates to a stretchable electronic device and a method for manufacturing the same. The stretchable electronic device overcomes the trade-off between the light-emitting region and the maximum tensile strength of a two-dimensional stretchable display and can exhibit a high tensile strength while having excellent initial driving performance. In addition, the stretchable electronic device has the advantage of being applicable to various electronic devices by eliminating the high-temperature and wet processes of existing three-dimensional stretchable display technology.

Inventors

• 유승협
• 김수본
• 이동균
• 김준호

Assignees

• 한국과학기술원

Dates

Publication Date

20260511

Application Date

20240820

Claims (20)

1. Elastic material; An adhesive layer disposed on the above elastic substrate; An anti-adhesion layer disposed on the adhesive layer so as not to cover the edges of the adhesive layer; A plurality of islands spaced apart from each other on the adhesive layer and the anti-adhesion layer; and It includes interconnectors connecting the aforementioned plurality of islands, A flexible electronic device in which the anti-adhesion layer exhibits weak adhesion to the island compared to the adhesive layer.
2. A flexible electronic device according to claim 1, wherein the plurality of islands can be arranged in a two-dimensional structure on the same plane and arranged in a three-dimensional structure on different planes or on the same spherical plane.
3. The flexible electronic device according to claim 1, wherein the interconnector is flexible so that the distance between the islands connected by the interconnector becomes longer or shorter on the same plane, and is bent so that the islands connected by the interconnector can be located on different planes.
4. delete
5. In claim 1, the island disposed on the anti-adhesion layer is a flexible electronic device that is spaced apart from the anti-adhesion layer or can come into contact with the anti-adhesion layer.
6. A flexible electronic device according to claim 1, wherein the effective adhesion work of the anti-adhesion layer and the island disposed on the anti-adhesion layer is 0.01 to 0.30 J/ m² .
7. A flexible electronic device according to claim 1, wherein the ratio of the area of the effective area, which is the area occupied by the island, to the unit area, which is the repeating unit of the island and the interconnect connected thereto, is 70% or more.
8. A flexible electronic device according to claim 1, wherein the maximum tensile strength based on both axes is 20% or more when the plurality of islands are arranged in a checkerboard shape.
9. A flexible electronic device according to claim 1, wherein the anti-adhesion layer has an intaglio pattern formed on the surface in contact with the island.
10. A flexible electronic device according to claim 9, wherein the ratio of the area occupied by the intaglio pattern to the total area of the anti-adhesion layer is 10% to 97%.
11. A flexible electronic device according to claim 1, wherein the anti-adhesion layer has a thickness of 0.1 μm to 10 μm.
12. A flexible electronic device according to claim 1, wherein the island disposed on the anti-adhesion layer comprises an island substrate and an electronic element formed on at least one surface of the island substrate.
13. In paragraph 12, the electronic device is a stretchable electronic device, wherein the electronic device is a stretchable organic light-emitting diode, a photoelectronic device, a transistor, a solar cell, or a battery.
14. A flexible electronic device according to claim 1, wherein the island disposed on the adhesive layer is the same or different from the island disposed on the anti-adhesion layer.
15. A flexible electronic device according to claim 1, wherein an organic light-emitting diode is applied to an island disposed on the anti-adhesion layer, and a driving element for driving the organic light-emitting diode is applied to an island disposed on the adhesive layer.
16. A step of applying tensile force to an elastic material to stretch it; Step of placing an adhesive layer on a tensioned elastic substrate; A step of placing an anti-adhesion layer so as not to cover the edges of the adhesive layer; A step of arranging a plurality of islands connected by interconnectors on the adhesive layer and the anti-adhesion layer; and A method for manufacturing a flexible electronic device comprising the step of removing the tensile force applied to the elastic substrate.
17. A method for manufacturing a flexible electronic device according to claim 16, wherein in the step of applying a tensile force to the elastic material to stretch it, the elastic material is stretched in both axial directions on the same plane as the elastic material.
18. A method for manufacturing a flexible electronic device according to claim 16, wherein in the step of placing the anti-adhesion layer, a composition for forming an anti-adhesion layer is applied to a template having a raised pattern corresponding to a desired intaglio pattern, and at least one of a drying, polymerization, or curing process is performed to form an anti-adhesion layer, and then the anti-adhesion layer is transferred to the adhesive layer.
19. A method for manufacturing a flexible electronic device according to claim 16, wherein in the step of arranging a plurality of islands connected by the interconnectors, a plurality of islands are formed, interconnectors connecting them are formed, and then arranged on an adhesive layer and an anti-adhesion layer.
20. A method for manufacturing a flexible electronic device according to claim 16, wherein in the step of removing the tensile force applied to the elastic substrate, a compressive force is applied to a plurality of islands disposed on an anti-adhesion layer and interconnectors connecting them to induce a three-dimensional structural arrangement of the plurality of islands.

Description

Stretchable electronic device and manufacturing method thereof This application relates to a flexible electronic device and a method for manufacturing the same. Recently, in the field of display technology, research is actively underway to provide stretchable displays that can freely expand and contract the screen size and freely change the shape of the screen, going beyond flat, curved, foldable, and rollable displays. One of the technologies introduced for commercializing such stretchable displays is the use of rigid islands and interconnects. The development direction of this technology focuses on improving the elasticity of interconnects connecting two-dimensionally arranged islands. However, this structure has a fundamental limitation in that it is difficult to simultaneously improve both elasticity and resolution, as sacrificing display resolution is inevitable to improve the elasticity of the interconnects. Therefore, to overcome these limitations, a stretchable display with a three-dimensional structure that deviates from the two-dimensional structure has been introduced. Mechanically guided assembly is known as a technology for providing a stretchable display with a three-dimensional structure. A method has been introduced in which, as one of the above technologies, an electronic device having a sacrificial layer formed on a pre-stretched elastic substrate is transferred and bonded, and after removing the sacrificial layer, the stretched elastic substrate is returned to form a three-dimensional structure. Another technique has been introduced in which an elastic substrate having a predetermined shape is stretched, an electronic element is selectively attached to the predetermined shape of the elastic substrate, and the stretched elastic substrate is returned to form a three-dimensional structure. However, existing studies have fixed the elastic substrate and electronic device through covalent bonding, which necessarily involves high-temperature processes of over 180°C or wet etching processes such as sacrificial layer removal, and thus there have been technical limitations in realizing electronic devices that are vulnerable to high-temperature and wet processes into three-dimensional structures. FIG. 1 is a perspective view sequentially illustrating, as one embodiment, an elastic substrate (10) stretched along both axes, an adhesive layer (20) to be laminated thereon, an anti-adhesion layer (30), and a plurality of islands (41) arranged on a two-dimensional plane. FIG. 2 is a perspective view of a flexible electronic device manufactured by sequentially laminating an adhesive layer (20), an anti-adhesion layer (30), and a plurality of islands (41) arranged on a two-dimensional plane onto an elastic substrate (10) that is stretched along both axes of FIG. 1, and then removing the tension applied to the elastic substrate (10). FIG. 3 is a cross-sectional view schematically illustrating the state in which the island (41a) is separated from the anti-adhesion layer (30) according to one embodiment. FIG. 4 is a cross-sectional view schematically illustrating the state in which an island (41a) is in contact with an anti-adhesion layer (30) according to one embodiment. Figure 5 is an enlarged view of the part indicated by the dotted circle (P) in Figure 2. FIG. 6 is a perspective view of a flexible electronic device in which a plurality of islands (41a) are arranged in a three-dimensional structure according to one embodiment. FIG. 7 is a perspective view of a flexible electronic device in which a plurality of islands (41a) are arranged on a two-dimensional plane according to one embodiment. Figure 8 is a graph showing the adhesion strength with the island according to the area ratio of the intaglio pattern of the anti-adhesion layer prepared in Examples 1 to 3. FIG. 9 is a photograph of the stretchable electronic device manufactured in Examples 1 to 3 taken with a camera equipped with a micro-lens and a scanning electron microscope image. Figure 10 is a photograph for evaluating the elasticity and driving performance according to two-dimensional deformation of the stretchable electronic device manufactured in Example 3. Figure 11 is a diagram illustrating r/R, an indicator of three-dimensional deformation in Figures 12 and 13. Figure 12 is a graph showing the maximum strain according to the three-dimensional deformation of the stretchable electronic device manufactured in Example 3. Figure 13 is a photograph for evaluating the elasticity and driving performance according to the three-dimensional deformation of the stretchable electronic device manufactured in Example 3. Figure 14 is a graph showing the results of evaluating current density and brightness according to voltage while applying a two-dimensional deformation to the stretchable electronic device manufactured in Example 3. Figure 15 is a graph showing the results of evaluating current efficiency according to brightness while applying a two-dimensi