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KR-20260066646-A - LIGHT-EMITTING DISPLAY DEVICE, METHOD FOR MANUFACTURING SUCH A DEVICE AND LIGHT-EMITTING DISPLAY SYSTEM

KR20260066646AKR 20260066646 AKR20260066646 AKR 20260066646AKR-20260066646-A

Abstract

One aspect of the present invention relates to a method for manufacturing a light-emitting display device from islands separated by trenches, the method comprising: - filling the trenches with insulating structural elements; - forming a protective strip (108) that partially covers each of the islands and overlaps with the structural elements; - partially etching the structural elements to form a filler (109) under the protective strips so that the protective strips have cantilevered portions (110a, 110b); and - depositing an organic layer resulting in two distinct separated portions, wherein a first portion extends continuously over each island and protective strip and a second portion extends over a substrate.

Inventors

  • 발롯, 클레멘트
  • 가쎄, 아드리안
  • 하스, 건더

Assignees

  • 꼼미사리아 아 레네르지 아토미끄 에뜨 옥스 에너지스 앨터네이티브즈
  • 미크로올레드

Dates

Publication Date
20260512
Application Date
20251104
Priority Date
20241104

Claims (19)

  1. A method (300) for manufacturing a light-emitting display device (200) from a precursor (100), wherein the precursor (100) comprises a plurality of islands (101) disposed on a substrate (102), each island (101) comprises a support layer (104) extending over the substrate (102); and a conductive layer (103) extending over the support layer (104), wherein the islands are separated in pairs by a trench (106), and the method (300) comprises: - A step of charging each trench (106) separating the island (101) with a structural element (107) that electrically insulates the island (101), wherein for each trench (106), the step of charging is performed until the structural element (107) reaches the top of the island (101) separated by the trench (106); - A step of forming at least one protective strip (108), wherein each protective strip (108) overlaps with a trench (102) separating the two islands (101) and covers a structural element (107) extending from a trench (106) to connect the two islands (101) between them, and each protective strip (108) partially covers each of the two islands (101) being connected; - A step of selectively partially etching the structural element (107) with respect to each protective strip (108) and the conductive layer (103) of the island (101), wherein the partially etching step comprises at least one isotropic etching step, wherein the partially etching step is performed to retain only the portion (109) of the structural element (107) disposed under each protective strip (108) and said portion (109) forming a filler for each protective strip (108), and further wherein the partially etching step is performed such that at least one portion (110a, 110b) of each protective strip (108) extends cantilevered beyond the filler (109) supporting it; and - A method for manufacturing a light-emitting display device, comprising the step of anisotropically depositing an organic layer (201) at an angle substantially perpendicular to the substrate (102) to result in two parts (201-1, 201-2) including a first part (201-1) that is separated from the organic layer (201) and extends continuously over each island (101) and each protective strip (108), and a second part (201-2) that extends over the substrate (102), wherein the deposition thickness of the organic layer (201) is selected such that the second part of the organic layer (201) does not reach the at least one cantilevered part (110a, 110b) of each protective strip (108).
  2. In claim 1, A method for manufacturing a light-emitting display device, wherein the step of partially etching the above structural element (107) is performed such that the lateral spacing (D110) of the at least one cantilever portion (110a, 110b) of each protective strip (108) exceeds 100 nm in absolute terms with respect to the filler (109) supporting it.
  3. In claim 1 or 2, A method for manufacturing a light-emitting display device, wherein for each trench (106), the step of filling is performed until the structural element (107) extends beyond the conductive layer (103) of the two islands (101) separated by the trench (106) by a height of 10 nm to 100 nm.
  4. In claim 3, A method for manufacturing a light-emitting display device, wherein each island (101) includes a sacrificial layer (105) extending over a conductive layer (103) before filling each trench (106), and the step of filling each trench (106) with the structural element (107) is performed such that the structural element (107) reaches the top of the sacrificial layer (105) extending over the island (101).
  5. In claim 4, A method for manufacturing a light-emitting display device, further comprising the step of optionally etching the sacrificial layer (105) of each island (101) for a structural element (107) after filling each trench (106) and before forming each protective strip (108), wherein the etching is performed so as to stop at the conductive layer (103) of the island (101).
  6. In claim 4 or 5, For each trench (106), the step of filling with the structural element (107) is: - A step of depositing a layer of electrical insulating material to completely fill the trench (106); - A method for manufacturing a light-emitting display device comprising the step of polishing the layer of the insulating material so as to stop at the sacrificial layer (105) of each island (101).
  7. In claim 4 or 5, For each trench (106), the step of filling with the structural element (107) is: - A step of conformally depositing a dielectric layer in the above trench (106); - A step of depositing a layer of filler material on the dielectric layer to completely fill the trench (106); - A method for manufacturing a light-emitting display device comprising the step of polishing a dielectric layer and a filler layer so as to stop at each island (101) sacrificial layer (105).
  8. In claim 7, A method for manufacturing a light-emitting display device, wherein the above-mentioned filler is amorphous silicon or polycrystalline silicon.
  9. In any one of claims 1 to 8, A method for manufacturing a light-emitting display device comprising, before forming each protective strip (108), creeping or expanding the structural element (107) across a portion of the conductive layer of each island (101) to form at least one continuous, ridge-free free surface extending from the conductive layer (103) of one of the islands (101) to the conductive layer of another island (101), wherein each free surface has a slope of -45 to 45 degrees, preferably -20 to +20 degrees, measured with respect to the substrate (102).
  10. In any one of claims 1 to 9, A method for manufacturing a light-emitting display device in which each protective strip (108) is electrically insulated.
  11. In any one of claims 1 to 10, A method for manufacturing a light-emitting display device, wherein the step of partially etching the above structural element (107) comprises, for example, alternately at least one anisotropic etching step and at least one isotropic etching step, each anisotropic etching step is performed in a direction substantially perpendicular to the substrate (102).
  12. In any one of claims 1 to 11, A method for manufacturing a light-emitting display device, comprising the step of depositing an organic layer (201) and then depositing an additional conductive layer (204) anisotropically, resulting in two parts (204-1, 204-2) separated from the additional conductive layer (204), wherein the additional conductive layer (204) includes a first part (204-1) of the additional conductive layer (204) that extends continuously over a first part (201-1) of the organic layer (201) and a second part (204-2) of the additional conductive layer (204) that extends over a second part (201-2) of the organic layer (201), and wherein the deposition thickness of the additional conductive layer (204) is selected such that the second part (204-2) of the additional conductive layer (204) does not reach the at least one cantilevered part (110a, 110b) of each protective strip (108).
  13. In any one of claims 1 to 12, A method for manufacturing a light-emitting display device, wherein the step of partially etching the above structural element (107) is further performed to partially etch the support layer (104) of each island (101), so that for each island (101), at least one part (114) of the conductive layer (103) of the island (101) extends in a cantilevered manner beyond the support layer (104) of the island (101).
  14. A light-emitting display device (200) comprising a plurality of islands (101) disposed on a substrate (102), wherein each island comprises a support layer (104) extending over the substrate (102) and a conductive layer (103) extending over the support layer (104), and the device: - At least one trench (106) separating the island (101) into two; - At least one protective strip (108), wherein each protective strip (108) overlaps with a trench (102) separating the two islands (101) and connects the two islands (101) to each other, and each protective strip (108) partially covers each of the two islands (101); - At least one filler (109) that at least partially fills the trench and electrically insulates the island (101) separated by the trench (106), wherein each filler (109) reaches or extends beyond the top of the two islands (101) separated by the trench (106), and each filler is placed below the protective strip (108) to support the protective strip (108) such that at least one part (110a, 110b) of the protective strip (108) extends cantileveredly over the filler (109); and - An organic layer (201) having two distinctly separated parts (201-1, 201-2), comprising a first part (201-1) extending continuously over each island (101) and each protective strip (108), and a second part (201-2) extending over a substrate (102) without reaching the at least one cantilevered part (110a, 110b) of each protective strip (108).
  15. In claim 14, A light-emitting display device in which the lateral spacing (D110) of at least one cantilever portion (110a, 110b) of each protective strip (108) exceeds 100 nm with respect to the supporting filler (109).
  16. In claim 14 or 15, The above-mentioned at least one filler (109) is made of an electrical insulating material, and is a light-emitting display device.
  17. In any one of claims 14 to 16, A light-emitting display device comprising: a dielectric layer for electrically insulating an island (101) separated by the at least one filler (109); and a filler that serves as a support for a protective strip (108), wherein the dielectric layer of the at least one filler separates the filler of the at least one filler from each island (101).
  18. In any one of claims 14 to 16, The above-mentioned at least one filler (109) has a continuous, ridgeless surface to which a protective strip (108) extends, said continuous, ridgeless surface extends from a conductive layer (103) of one of the islands (101) to a conductive layer of another island (101), and each continuous, ridgeless surface has a slope of -45 to 45 degrees, preferably -20 to +20 degrees, measured with respect to the substrate (102), in a light-emitting display device.
  19. - Device (200) according to any one of claims 14 to 18; and - A light-emitting display system comprising an active addressing matrix including a plurality of transistors, wherein each transistor among the plurality of transistors is connected to a conductive layer (103) of one of the islands (101) of the device (200).

Description

Light-Emitting Display Device, Method for Manufacturing Such a Device and Light-Emitting Display System The technical field of the present invention relates to optoelectronic devices, in particular to matrix display devices having an organic photovoltaic layer. The present invention relates to a method for manufacturing an OLED (organic light-emitting diode) type light-emitting display device and a system of such a device. The present invention is advantageously applied to the manufacture of display screens for electronic devices, particularly to the manufacture of high-resolution color display screens such as AMOLED (Active Matrix Organic Light Emitting Diode) display screens. The term "high resolution" means pixels having a size of less than 15 μm. In the field of matrix display devices having an organic photoluminescent layer, an OLED-type matrix microdisplay having pixels arranged at a pitch of less than 20 µm, typically 4 µm to 12 µm, is known. When this type of matrix display is color, each pixel is subdivided into sub-pixels of different colors (typically three colors: red, green, and blue), and these sub-pixels work together to make the pixel emit the desired color. The surface of the sub-pixels can be rectangular, square, or other shapes (e.g., octagonal), and their size may vary depending on the color. The typical size of the sub-pixels may be in the range of 1 µm to 20 µm. Each sub-pixel is generally formed of multiple stacked layers comprising a lower electrode (anode) deposited on a common substrate, multiple organic layers (at least one of which is a light-emitting layer) forming an OLED stack on each lower electrode, and an upper electrode (cathode). Literature FR3079909A1 and US2023/0041252A1 describes structures for forming such small OLED pixels (or OLED sub-pixels) with improved industrial reliability. These structures share the common advantage of allowing smooth discretization of the OLED stack and cathode to form pixels (or sub-pixels). The term "smooth discretization" refers to a structuring method that preserves the performance of the OLED stack. In particular, the provided solution consists of performing the individualization of the OLED stack in a different way than masking and removal steps that generally require an environment harmful to organic materials (humidity, temperature above 90°C, solvent, ultraviolet light, etc.). Accordingly, document FR3079909 A1 describes a first OLED display device in which the lower electrodes of each sub-pixel are separated from one another by an insulating wall that rises vertically from the substrate. Each wall serves as a separation wall between two adjacent sub-pixels. The same document, FR3079909, describes a second apparatus in which an insulating wall is replaced by trenches on which an insulating layer is deposited. Insulating walls and trenches are formed before the OLED stack is deposited by thermal evaporation and serve the same purpose. Because evaporative deposition technology is primarily directivity, the OLED stack is preferentially deposited onto the horizontal walls of the device rather than on the sidewalls of the insulating walls or trenches. Therefore, the OLED stack is divided (or individualized) at the insulating walls or trenches. However, in practice, the directionality of OLED stack deposition is never perfect. Therefore, organic particles can also be deposited on insulating walls or the sidewalls of trenches. These particles are undesirable because they degrade the insulation (electrical and optical) between sub-pixels. Subsequently, adjacent sub-pixels can interact with each other, for example, through capacitive coupling or parasitic currents. This phenomenon, known as crosstalk, leads to a degradation of the display device's performance. This phenomenon is further exacerbated when the sub-pixels are so-called "tandem" organic photovoltaic diodes, that is, when multiple OLED stacks are stacked and connected in series through interconnection layers. Reference US2023/0041252A1 presents a solution to this problem by describing a sub-pixel separation wall disposed on a substrate and having a mushroom-shaped structure (or, according to the term used in this document, a "hang-over"). More precisely, this mushroom-shaped structure includes a lower portion having slanted sides that form the stem of the mushroom. It also includes an upper portion that is wider than the lower portion and covers an area of the substrate. This upper portion forms the cap of the mushroom. When the mushroom-shaped structure is placed in place, a sub-pixel is formed. Then, the OLED stack is deposited on top of this structure and split from the top. The splitting of the OLED stack is performed with satisfactory reliability because organic material cannot be deposited on areas of the substrate obscured by the top or on the sidewalls of the mushroom-shaped structure (the bottom is obscured by the top and cannot be accessed from above). Therefore, the deg