TWI685097B - Microled display and a method of forming the same - Google Patents

Abstract

A method of forming a micro light-emitting diode (microLED) display includes providing a substrate with a plurality of microLEDs and at least one integrated circuit disposed thereon; and forming a planarization layer to cover the microLEDs and the at least one integrated circuit. The planarization layer acts as both a light blocking layer and a corrosion-resistant layer.

Description

Micro-luminous diode display and forming method thereof

The present invention relates to a micro-luminescence diode, in particular to a method of forming a micro-luminescence diode display.

A micro-luminescent diode (microLED, mLED or μLED) display panel is a type of flat panel display, which is composed of individual microscopic light-emitting diodes with a size level of 1-10 microns. Compared with traditional liquid crystal display panels, micro light-emitting diode display panels have greater contrast and faster response time, and consume less power. Although micro-emitting diodes and organic light-emitting diodes (OLEDs) also have the characteristics of low power consumption, micro-emitting diodes use three- to five-group diode technology (such as gallium nitride), so they are compared The organic light-emitting diodes have higher brightness, higher luminous efficacy and longer life.

The first figure shows a cross-sectional view of a conventional micro-light emitting diode display 100, on which a micro-light emitting diode 12 and an integrated circuit 13 are provided on a glass substrate 11. The first protective layer 14 is formed on the integrated circuit 13, and the second protective layer 15 is entirely formed on the micro-light emitting diode 12 and the integrated circuit 13. Since the height of the integrated circuit 13 (for example, 150 micrometers) is generally higher than the height of the microluminescent diode 12 (for example, less than 10 micrometers), the upper surface of the microluminescent diode display 100 has a sharp contrast profile. When the micro-luminescent diode display 100 is turned over and the subsequent process is performed on the back side, this sharp contrast profile may cause uneven pressure. Therefore, the glass substrate 11 is easily broken or/and the integrated circuit 13 is damaged due to pressure.

Therefore, there is an urgent need to propose a novel method to form a micro light-emitting diode display to overcome the lack of the traditional micro-light emitting diode display.

In view of the above, one of the objects of the embodiments of the present invention is to provide a method for forming a micro-luminescent diode display, which has a simplified process or/and has a flat upper surface.

According to an embodiment of the present invention, a method of forming a micro light-emitting diode display includes the following steps. A substrate is provided, on which a plurality of micro light-emitting diodes and at least one integrated circuit are provided. A flat layer is formed to cover the micro-emitting diode and the integrated circuit. The flat layer serves as a light shielding layer and an anti-corrosion layer.

The cross-sectional views and top views of the second to fourth B diagrams show the method of forming the micro-luminescent diode display 200 according to an embodiment of the present invention.

As shown in the cross-sectional view of FIG. 2A and the top view of FIG. 2B, a substrate 21 is provided, on which a micro-luminescent diode 22 and at least one integrated circuit 23 are provided. The substrate 21 may include glass or other materials suitable for supporting the micro-luminescent diode 22 and the integrated circuit 23. The integrated circuit 23 may be a driver, and may be provided on the substrate 21 using glass-on-glass (COG) technology. Although the figure only shows a few micro-emitting diodes 22, there are usually a large number of micro-emitting diodes 22 on the substrate 21. In this embodiment, the height of the integrated circuit 23 (for example, 150 microns) is much larger than the height of the micro-emitting diode 21 (for example, less than 10 microns).

The light guide layer 221 may cover the micro-luminescent diode 22 to facilitate the transmission of light generated by the micro-luminescent diode 22. The reflective layer 222 (eg, metal) may cover the light guide layer 221 to reflect the light generated by the micro-luminescent diode 22.

As shown in the cross-sectional view of FIG. 3A and the top view of FIG. 3B, a seal frame (sealant) 24 may be formed on the substrate 21 to surround at least a portion of the micro-luminescent diode 22 and Integrated circuit 23. In this embodiment, the sealant 24 is rectangular and can be disposed around the substrate 21, and the sealant 24 includes a first glue material (such as an organic polymer). The sealant 24 in this embodiment may be closed and continuous without interruption. According to one of the features of this embodiment, the height of the sealant 24 is greater than the height of the integrated circuit 23.

As shown in the cross-sectional view of the fourth diagram A and the top view of the fourth diagram B, the internal space defined by the frame glue 24 can be filled with a second glue material (such as epoxy or silicone-based) Glue) to form a flat layer 25 (which has a flat upper surface), which covers the micro-luminescent diode 22 and the integrated circuit 23. The height of the flat layer 25 is greater than the height of the integrated circuit 23, but smaller than the height of the sealant 24. In this embodiment, the second glue material of the flat layer 25 may be different from the first glue material of the sealant 24. The viscosity of the flat layer 25 (or the filled second glue) is less than the viscosity of the sealant 24 (or the filled first glue). According to another feature of this embodiment, the degree of condensation (liquid to solid) of the flat layer 25 (or the filled second glue material) is sufficiently small to prevent the glue material from shrinking during the drying process, resulting in the substrate 21 (E.g. glass substrate) deformed or broken.

It is worth noting that if the flat layer 25 is viscous enough to limit itself to a predetermined space (which does not flow outward) to cover the micro-luminescent diode 22 and the integrated circuit 23, the sealant 24 can be omitted.

According to still another feature of this embodiment, the flat layer 25 is doped with a dark or black dye to form a dark or black color as a light blocking layer to prevent light from irradiating the integrated circuit 23. The flat layer 25 can also serve as a waterproof layer to prevent the integrated circuit 23 from being affected by moisture. In this embodiment, the flat layer 25 (or the filled second glue material) may include a molding compound material (for example, silicone).

According to yet another feature of this embodiment, the flat layer 25 (or the filled second glue material) can serve as a corrosion-resistant layer to prevent the reflective layer 222 from being corroded by moisture or/and oxidation. In this embodiment, the flat layer 25 may include room-temperature-vulcanizing (RTV) materials, such as RTV silicone.

According to the above embodiment, the method of forming the micro-luminescent diode display 200 is simplified compared to the conventional method shown in the first figure. In this embodiment, a single process step is used to form a single layer (that is, a flat layer 25) to cover the micro light-emitting diode 22 and the integrated circuit 23. Looking back at the first image, it uses two process steps to form two layers (ie, the first protective layer 14 and the second protective layer 15). In addition, as shown in the fourth diagram A, the micro-luminescent diode display 200 formed in this embodiment has a flat upper surface, but the upper surface of the first diagram has a sharp contrasting contour, thus causing uneven pressure. Therefore, the substrate 21 (such as a glass substrate) of the present embodiment is not easily broken or/and the integrated circuit 23 is not damaged by pressure.

The above are only the preferred embodiments of the present invention and are not intended to limit the scope of the patent application of the present invention; all other equivalent changes or modifications made without departing from the spirit of the invention should be included in the following Within the scope of patent application.

100‧‧‧Micro LED display 11‧‧‧Glass substrate 12‧‧‧Microluminescence diode 13‧‧‧Integrated circuit 14‧‧‧The first protective layer 15‧‧‧Second protective layer 200‧‧‧Micro LED display 21‧‧‧ substrate 22‧‧‧Microluminescence diode 221‧‧‧Light guide layer 222‧‧‧Reflective layer 23‧‧‧Integrated circuit 24‧‧‧ frame glue 25‧‧‧flat layer

The first figure shows a cross-sectional view of a conventional micro-luminescence diode display, which is provided with a micro-luminescence diode and an integrated circuit on a glass substrate. The cross-sectional view and the top view of the second to fourth B diagrams show a method of forming a micro light-emitting diode display according to an embodiment of the present invention.

200‧‧‧Micro LED display

21‧‧‧ substrate

22‧‧‧Microluminescence diode

221‧‧‧Light guide layer

222‧‧‧Reflective layer

23‧‧‧Integrated circuit

24‧‧‧ frame glue

25‧‧‧flat layer

Claims (18)

A method for forming a micro-luminous diode display includes: providing a substrate on which a plurality of micro-luminous diodes and at least one integrated circuit are provided; and forming a flat layer to cover the micro-luminous diodes and the at least one An integrated circuit; wherein the flat layer serves as a light-shielding layer and an anti-corrosion layer; wherein the height of the integrated circuit is greater than the height of the micro-emitting diodes; wherein the flat layer contains dark or black dyes as a light-shielding layer to prevent the Light from some micro-emitting diodes illuminates the integrated circuit. The method for forming a microluminescent diode display according to item 1 of the patent application scope, wherein the substrate includes glass. The method for forming a micro-luminescent diode display according to item 1 of the patent application scope, wherein the flat layer includes a room temperature vulcanization material. The method for forming a microluminescent diode display according to item 1 of the patent application scope, wherein the flat layer comprises epoxy resin or silicone resin-based glue. The method for forming a micro-luminescent diode display according to item 1 of the patent application scope, wherein the flat layer includes a molded material. The method for forming a micro light-emitting diode display according to item 1 of the scope of the patent application further includes: before forming the flat layer, forming a sealant to surround the micro-light emitting diodes and the at least one on the substrate In an integrated circuit, the height of the sealant is greater than the height of the flat layer and the integrated circuit. The method for forming a micro-luminescent diode display according to item 6 of the patent application scope, wherein the viscosity of the flat layer is less than the viscosity of the sealant. The method for forming a microluminescent diode display according to item 1 of the scope of the patent application further includes: before forming the flat layer, forming a light guide layer to cover the microluminescent diodes; and forming a reflective layer on the On the light guide layer. The method for forming a micro-luminescent diode display according to item 1 of the scope of the patent application, wherein the condensability of the flat layer is such that the flat layer is not deformed or cracked during the drying process. A micro-luminescence diode display, comprising: a substrate; a plurality of micro-luminescence diodes and at least one integrated circuit, arranged on the substrate; and a flat layer covering the micro-luminescence diodes and the at least one integrated body Circuit; wherein the flat layer serves as a light-shielding layer and an anti-corrosion layer; wherein the height of the integrated circuit is greater than the height of the micro-emitting diodes; wherein the flat layer contains dark or black dyes as a light-shielding layer to prevent the micro-light emitting two Light from the polar body illuminates the integrated circuit. The micro light emitting diode display according to item 10 of the patent application scope, wherein the substrate comprises glass. The micro light emitting diode display according to item 10 of the patent application scope, wherein the flat layer includes a room temperature vulcanization material. The micro light emitting diode display according to item 10 of the patent application scope, wherein the flat layer comprises an epoxy resin or a silicone resin-based glue material. The micro light-emitting diode display according to item 10 of the patent application scope, wherein the flat layer comprises a molded material. The micro light-emitting diode display according to item 10 of the scope of the patent application further includes: a frame glue disposed on the substrate to enclose the micro-light emitting diodes, the at least one integrated circuit and the flat layer, The height of the sealant is greater than the height of the flat layer and the integrated circuit. The micro light-emitting diode display according to item 15 of the patent application scope, wherein the viscosity of the flat layer is less than the viscosity of the sealant. The micro light emitting diode display according to item 10 of the patent application scope further includes: a light guide layer formed on the micro light emitting diodes but under the flat layer; and a reflective layer formed on the Between the light guide layer and the flat layer. The micro light-emitting diode display according to item 10 of the patent application range, wherein the condensation property of the flat layer is such that the flat layer will not be deformed or cracked during the drying process.

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