KR102601054B1 - Micro led assembly - Google Patents

Abstract

An embodiment of the present invention provides a micro LED assembly that can minimize changes in physical properties during the micro LED manufacturing process by forming vertical-type electrodes to be accommodated in a circuit board.

Description

Micro LED assembly{MICRO LED ASSEMBLY}

The present invention relates to a micro LED assembly, and more specifically, to a micro LED assembly that can minimize changes in mechanical stability and material properties during the manufacturing process of a micro LED panel by forming micro LED electrodes to be accommodated in a circuit board.

The content described below is merely for the purpose of providing background information related to embodiments of the present invention, and does not necessarily constitute prior art.

In general, LED is a well-known semiconductor light-emitting device that converts current into light. It has high light conversion efficiency, so it consumes very little energy, has a semi-permanent lifespan, and is an environmentally friendly green material. It is called the revolution of light and is used in electronics including information and communication devices. It has been widely used as a light source for display images in devices.

Recently, with the development of compound semiconductor technology, high-brightness red, orange, green, blue, and white LEDs have been developed, and these can be used in many applications such as traffic lights, cell phones, automobile headlights, outdoor electronic signs, LCD BLU (back light unit), and indoor and outdoor lighting. It is being applied in many fields, and active research continues both domestically and internationally. In particular, GaN-based compound semiconductors with a wide bandgap are materials used in the manufacture of LED semiconductors that emit light in the green, blue, and ultraviolet ranges. It is possible to manufacture white LED devices using blue LED devices, so there is much research on this. is being done.

Among these series of studies, research is continuing to utilize ultra-small LED devices manufactured in nano or micro units for use in lighting, displays, etc. Areas that continue to receive attention in these studies include electrodes that can apply power to ultra-small LED elements, alignment methods for utilization purposes and reduction of the space occupied by electrodes, electrode placement, and mounting methods of ultra-small LEDs on the arranged electrodes. It's about things.

A transparent display panel including such micro LEDs is implemented in a form that includes a conductive circuit board, and a transparent electrode formation manufacturing process is essential in the conductive circuit board manufacturing method. Transparent electrodes use a variety of materials such as ITO (Indium Tin Oxide), Nanowire, Metal Mesh, conductive polymer, Graphene, and Carbon Nanotube, and are manufactured depending on the material. There is a difference in the process. In particular, when manufacturing a circuit board using a transparent and flexible electrode material, there are limitations in that the electrode formation process is complicated and damage to the electrode material occurs.

In particular, in order to apply a transparent electrode to a micro LED panel, the electrode 20 of the micro LED panel 10 aligned as shown in FIG. 1 and the conductive circuit board 50 on which the transparent electrode 40 is formed are bonded. You can. At this time, solder 30 for joining the electrode 20 and the transparent electrode 40 is applied between the electrode 20 and the transparent electrode 40.

Specifically, when graphene is used as a material for forming a transparent electrode on the conductive circuit board 50 of the micro LED panel 10, PMMA/graphene is transferred, PMMA is removed, and then a graphene electrode pattern process is performed. You can. At this time, there is a problem that material properties such as sheet resistance characteristics of the transparent electrode are deteriorated because the residue of PMMA used for graphene transfer and the photoresist used in the photolithography process for forming the graphene electrode pattern remain in the graphene.

When manufacturing such a micro LED panel 10, a process that can be manufactured while minimizing degradation of the material properties of the conductive circuit board 50 is required.

The above-mentioned background technology is technical information that the inventor possessed for deriving the present invention or acquired in the process of deriving the present invention, and cannot necessarily be said to be known art disclosed to the general public before filing the application for the present invention.

An embodiment of the present invention provides a micro LED assembly without a separate bonding process by manufacturing a micro-sized LED electrode and forming a receiving portion in which the electrode can be accommodated on a substrate bonded to the electrode.

In addition, an embodiment of the present invention provides a micro LED assembly that can be manufactured while minimizing the deterioration of the physical properties of the conductive circuit board electrode material during the micro LED panel manufacturing process.

The object of the present invention is not limited to the problems mentioned above, and other objects and advantages of the present invention that are not mentioned can be understood through the following description and will be more clearly understood through examples of the present invention. Additionally, it will be appreciated that the objects and advantages of the present invention can be realized by means and combinations thereof as indicated in the patent claims.

A micro-LED assembly according to an embodiment of the present invention includes a micro-LED including an electrode portion; And it may include a circuit board including a receiving portion in which the electrode portion is accommodated.

At this time, the electrode portion faces the circuit board and includes a first electrode and a second electrode formed in different shapes, and the circuit board includes a first accommodating portion and a second accommodating portion in which the first electrode and the second electrode are accommodated. May include wealth.

The first electrode according to an embodiment of the present invention may be formed longer than the second electrode, and the first accommodating part may be formed to be deeper than the second accommodating part.

The first electrode and the second electrode according to an embodiment of the present invention may be formed with the same shape and the same inner diameter in the direction toward the circuit board.

The first electrode and the second electrode according to an embodiment of the present invention may be formed in different shapes and have different inner diameters.

At least one of the first accommodating part and the second accommodating part according to an embodiment of the present invention may be formed so that the inner diameter gradually increases toward the electrode part.

The width of the first accommodating part and the second accommodating part according to an embodiment of the present invention may be formed to be larger than that of the first electrode and the second electrode.

An embodiment of the present invention may further include solder applied between the first electrode and the second electrode and between the first accommodating part and the second accommodating part.

One of the first electrode and the second electrode according to an embodiment of the present invention may be a metal bonded to an n-type nitride semiconductor layer, and the other may be a metal bonded to a p-type nitride semiconductor layer.

The circuit board according to an embodiment of the present invention includes a first conductive layer laminated on one side facing the micro LED, an insulating layer laminated on the first conductive layer, and a second conductive layer laminated on the insulating layer. may include.

At this time, the first accommodating part and the second accommodating part may be formed by forming a portion of the insulating layer and the second conductive layer through at least one of drilling and etching.

Other aspects, features, and advantages in addition to those described above will become apparent from the following drawings, claims, and detailed description of the invention.

An embodiment of the present invention forms an electrode on a micro LED and forms a receiving portion in which the electrode is received on a circuit board bonded to the micro LED, thereby making it possible to manufacture a micro assembly without a separate work process for forming an electrode pattern on the circuit board. There will be.

Accordingly, the micro LED assembly manufacturing process can be simplified.

Additionally, since the electrode pattern process is not performed on the substrate, changes in the physical properties of the electrode material of the circuit board can be minimized.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

Figure 1 is a diagram schematically showing a conventional micro LED assembly.
Figure 2 is a diagram schematically showing a micro LED assembly according to an embodiment of the present invention.
FIG. 3 is a diagram showing the micro LED and circuit board of FIG. 2.
4 and 5 are diagrams showing a micro LED assembly according to another embodiment of the present invention.

Hereinafter, embodiments invented in the present specification will be described in detail with reference to the attached drawings. However, identical or similar components will be assigned the same reference numbers regardless of the reference numerals, and duplicate descriptions thereof will be omitted. The suffixes “module” and “part” for components used in the following description are given or used interchangeably only for the ease of preparing the specification, and do not have distinct meanings or roles in themselves. Additionally, in describing the embodiments invented in this specification, if it is determined that a detailed description of related known technologies may obscure the gist of the embodiments invented in this specification, the detailed description will be omitted. In addition, the attached drawings are only for easy understanding of the embodiments invented in the present specification, and the technical idea invented in the present specification is not limited by the attached drawings, and are included in the spirit and technical scope of the present invention. It should be understood to include all modifications, equivalents and substitutions.

Terms containing ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

When a component is said to be "connected" or "connected" to another component, it is understood that it may be directly connected to or connected to the other component, but that other components may exist in between. It should be. On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between.

Singular expressions include plural expressions unless the context clearly dictates otherwise.

In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Before explaining the drawings, the LED assembly according to an embodiment of the present invention will be described by taking a micro light-emitting diode, that is, a micro-LED assembly, as an example. However, it can be applied to LED assemblies other than micro LED assemblies. am.

Figure 2 is a diagram schematically showing a micro LED assembly according to an embodiment of the present invention.

Referring to FIG. 2, the micro LED assembly 1 is a circuit board including a micro LED 100 including an electrode portion 140 and a receiving portion 260 (see FIG. 3) in which the electrode portion 140 is accommodated. 200).

The micro LED 100 may have an electrode portion 140 formed on one side facing the circuit board 200, and the electrode portion 140 is accommodated in the receiving portion 260 formed on the circuit board 200 and is separated from the other side. It allows the micro LED 100 and the circuit board 200 to be assembled and manufactured without a bonding process.

The electrode portion 140 of the micro LED 100 is formed to face the circuit board 200. Specifically, the electrode unit 140 may be configured to include a first electrode 142 and a second electrode 144 of different shapes.

For example, the first electrode 142 and the second electrode 144 may have different shapes, or may have the same shape but different lengths (heights). Similarly, both shape and length may be formed differently. These features will be described in detail below with reference to the drawings.

One of the first electrode 142 and the second electrode 144 may be formed of a metal bonded to n-GaN, which is an n-type nitride semiconductor layer, and the other electrode may be formed of a metal bonded to n-GaN, which is a p-type nitride semiconductor layer. -Can be formed from a metal bonded with GaN.

As an example of the present invention, the first electrode 142 is formed of a metal bonded to n-GaN, an n-type nitride semiconductor layer, and the second electrode 144 is bonded to p-GaN, a p-type nitride semiconductor layer. It may be formed of metal, for example, the first electrode 142 and the second electrode 144 may be formed of an indium (In) and tin (Sn) metal-based electrode. The present invention is not limited by the metal forming (144).

These first electrodes 142 and second electrodes 144 may be deposited on the micro LED 100, and when the micro LED 100 and the circuit board 200 are bonded, the micro LED 100 and the circuit board 200 ) can be connected physically and electrically.

Referring to the drawing again, the receiving portion 260 formed on the circuit board 200 fixes the micro LED 100 with the electrode portion 140 of the micro LED 100 inserted. The method of forming the receiving portion 260 on the circuit board 200 may use any one of super drilling, laser drilling, etching, laser processing, etc. depending on the size and shape. The method of forming the receiving portion 260 is according to the present invention. does not limit

In addition, the circuit board 200 may be made of any one of materials such as GaN, SiC, ZnO, Si, GaP, and GaAs, which are transparent materials such as sapphire and glass. Alternatively, the circuit board 200 may be made of a flexible polymer material, such as polyimide. It may be formed of any one of the following: a flexible material containing an elastic body within the mid-body.

Meanwhile, the circuit board 200 includes a first conductive layer 242 laminated on one side facing the micro LED 100, an insulating layer 244 laminated on the first conductive layer 242, and an insulating layer on the insulating layer. It may include a laminated second conductive layer 246.

Here, the first conductive layer 242 may be implemented as a cathode, and the second conductive layer 246 may be implemented as an anode.

The first conductive layer 242, the insulating layer 244, and the second conductive layer 246 stacked on the circuit board 200 are accommodated in the receiving portion 260 by the electrode portion 140 of the micro LED 100. This is a configuration for electrical connection between the circuit board 200 and the micro LED 100. That is, a separate electrode corresponding to the electrode portion 140 of the micro LED 100 is not formed on the circuit board 200 of the embodiment of the present invention, but the electrode portion 140 is formed by bonding to the micro LED 100. A receiving portion 260 in which is received may be formed. In other words, the circuit board 200 of the embodiment of the present invention can be assembled and electrically connected to the micro LED 100 without the manufacturing process of forming a conventional electrode pattern.

The receiving portion 260 is formed by etching or drilling a portion of the circuit board 200, but may also be formed using a photoresist technique.

In this way, by forming an electrode on the micro LED 100 and forming a receiving portion 260 in which the electrode is received on the circuit board 200 bonded to the micro LED 100, an electrode pattern is formed on the circuit board 200. It becomes possible to manufacture micro assemblies without a separate work process. Specifically, when graphene is used as an electrode material on the circuit board of a micro LED panel, PMMA/graphene is transferred, PMMA is removed, and then a graphene electrode pattern process is performed. At this time, there was a problem that residues of PMMA used for graphene transfer and photoresist used in the photolithography process for forming graphene electrode patterns remained in graphene.

Since this electrode pattern process is not performed on the circuit board 200 of the embodiment of the present invention, changes in the physical properties of the electrode material of the circuit board 200 can be minimized. In addition, by forming a substrate on the micro LED, the micro LED assembly can be manufactured without a separate manufacturing process for forming an electrode pattern, thereby simplifying the LED assembly manufacturing process.

Figure 3 is a diagram showing the micro LED and circuit board of Figure 2, and Figures 4 and 5 are diagrams showing a micro LED assembly according to another embodiment of the present invention.

Referring to FIG. 3, the circuit board 200 may be formed by stacking a first conductive layer 242, an insulating layer 244, and a second conductive layer 246 on a substrate 220. The circuit board 200 formed by stacking can form a receiving portion 260 corresponding to the shape of the electrode portion 140 of the micro LED 100.

The receiving portion 260 is formed by, for example, etching the first receiving portion 262 by etching a portion of the first conductive layer 242 and partially or entirely etching the second insulating layer 244 from the first conductive layer 242. It may consist of one second receiving portion 264.

In an embodiment of the present invention, the receiving portion 260 is formed by etching, for example, but it can be formed through any one of the following methods, such as super drilling, laser drilling, or etching, depending on the diameter size or shape.

The micro LED 100 may have an electrode portion 140 formed on the LED substrate 120. The electrode unit 140 may be formed to face the micro LED 100 toward the circuit board 200, and each electrode may be formed to have a different shape or length (height).

For example, the first electrode 142 may be formed of metal bonded to an n-type nitride semiconductor layer, and the second electrode 144 may be formed of metal bonded to a p-type nitride semiconductor layer. Additionally, the length of the first electrode 142 may be longer than the length of the second electrode 144.

Here, the first electrode 142 may be formed longer than the second electrode 144, and the first accommodating part 262 may be formed deeper than the second accommodating part 264. That is, the first accommodating part 262 and the second accommodating part 264 may be formed to correspond to the shapes of the first electrode 142 and the second electrode 144.

At this time, the length of the first electrode 142 may be sufficiently longer than the length of the second electrode 144. For example, the first electrode 142 may be formed to span from the first conductive layer 242 of the circuit board 200 to the second insulating layer 244, and the second electrode 144 may be formed across the circuit board 200. It may be formed to be accommodated in the first conductive layer 242. As one of the electrode parts 140 is formed to be long, the electrode part 140 can be accommodated in the receiving part 260 at a position corresponding to its shape. Accordingly, assembly according to shape alignment can be performed without a separate assembly process for accommodating the electrode portion 140 in the receiving portion 260.

In addition, since one of the electrode parts 140 is formed to be sufficiently long, the electrode part 140 can be accommodated in the receiving part 260 without minimizing shaking.

Referring again to FIG. 3, the width of the first accommodating part 262 and the second accommodating part 264 may be formed to be larger than the width of the first electrode 142 and the second electrode 144 (d1 in FIG. 3 and d2). This means that assembly such as interference fitting is not required when the electrode portion 140 is accommodated in the receiving portion 260, and the first electrode 142 and the second electrode 144 are inserted into the first receiving portion 262 and the second electrode portion 260. By inserting and assembling the receiving portion 264, the micro LED 100 and the circuit board 200 can be assembled and bonded without a separate assembly process.

In addition, as the width of the first accommodating part 262 and the second accommodating part 264 is formed to be larger than the width of the first electrode 142 and the second electrode 144, the electrode part 140 and the accommodating part 260 ) Electrical short circuit can be prevented by preventing contact with the inner wall.

Meanwhile, in an embodiment of the present invention, the first accommodating part 262 and the second accommodating part 264 are formed to be larger than the width of the first electrode 142 and the second electrode 144, but in other embodiments, the first accommodating part 262 and the second accommodating part 264 In order to prevent an electrical short circuit between the electrode 142 and the second electrode 144, the width of the first accommodating part 262 is formed to be larger than the first electrode 142, and the second accommodating part 264 is formed to be larger than the second electrode 142. It can also be formed the same as (144).

At this time, the degree of bonding between the electrode portion 140 and the receiving portion 260 can be improved by applying solder to one side of the circuit board 200. That is, before the electrode portion 140 is accommodated in the receiving portion 260, solder is applied between the electrode portion 140 in contact with the circuit board 200 to form the receiving portion 260 and the electrode portion 140. It can be formed so that joining is possible.

Referring to the drawings again, the first electrode 142 and the second electrode 144 may be formed to have the same shape and have the same inner diameter. For example, the first electrode 142 and the second electrode 144 may be formed in the same shape, such as circular or polygonal, and each electrode may have the same inner diameter, but differ only in length.

Alternatively, the first electrode 142 and the second electrode 144 may be formed in different shapes. For example, the first electrode 142 may be formed in a circular shape, and the second electrode 144 may be formed in a polygonal shape.

In an embodiment of the present invention, the first electrode 142 and the second electrode 144 will be described as an example in which the first electrode 142 and the second electrode 144 are formed in different shapes and/or heights. The present invention is not limited by shape and height.

When the electrode portion 140 is accommodated in the receiving portion 260 by electrodes formed in different shapes as described above, the electrode portion 140 is accommodated according to the shape, so that alignment can be more easily achieved.

Referring to FIG. 5 , at least one of the first accommodating part 262 and the second accommodating part 264 may be formed so that the inner diameter gradually increases toward the electrode part 140 . Specifically, the diameter D1 of the receiving groove formed in the first conductive layer 242 may be smaller than the diameter D2 of the receiving groove formed in the second insulating layer 244.

When the electrode portion 140 is accommodated in the receiving portion 260 according to the shape of the receiving portion 260, a separate solder is applied while being caught in the receiving groove diameter D1 formed in the first conductive layer 242. The electrode unit 140 can be fixed to the receiving unit 260 without any work.

Accordingly, when the electrode portion 140 of the micro LED 100 is aligned with the circuit board 200, assembly of the micro LED 100 and the circuit board 200 can be possible without using a separate member.

In this way, by forming an electrode on the micro LED 100 and forming a receiving portion 260 in which the electrode is received on the circuit board 200 bonded to the micro LED 100, an electrode pattern is formed on the circuit board 200. It becomes possible to manufacture micro assemblies without a separate work process.

Accordingly, the micro LED assembly manufacturing process can be simplified.

Additionally, since the electrode pattern process is not performed on the substrate, changes in the physical properties of the electrode material of the circuit board 200 can be minimized.

The description of the embodiments of the present invention described above is for illustrative purposes, and a person skilled in the art of the present invention can easily transform it into another specific form without changing the technical idea or essential features of the present invention. You will be able to understand that Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as unitary may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention.

Claims (9)

As a Micro-LED assembly,
A micro LED with a plurality of electrode parts stacked on one side; and
It includes a circuit board including a receiving portion in which the electrode portion is accommodated,
The electrode portion faces the circuit board and includes a first electrode and a second electrode formed in different shapes in at least one of height and width,
The circuit board includes a first accommodating part and a second accommodating part in which the first electrode and the second electrode are accommodated,
The first electrode is formed longer than the second electrode,
The first accommodating part is deeper than the second accommodating part,
Micro LED assembly.
delete According to paragraph 1,
The first electrode and the second electrode are formed with the same shape and the same inner diameter in the direction toward the circuit board,
Micro LED assembly.
According to paragraph 1,
The first electrode and the second electrode are formed in different shapes and have inner diameters of different sizes,
Micro LED assembly.
According to paragraph 1,
At least one of the first accommodating part and the second accommodating part is formed so that the inner diameter gradually increases toward the electrode part,
Micro LED assembly.
According to paragraph 1,
The widths of the first accommodating part and the second accommodating part are,
larger than the first electrode and the second electrode,
Micro LED assembly.
According to paragraph 1,
Further comprising solder applied between the first electrode and the second electrode and between the first accommodating part and the second accommodating part,
Micro LED assembly.
In paragraph 1,
One of the first electrode and the second electrode is a metal bonded to an n-type nitride semiconductor layer, and the other is a metal bonded to a p-type nitride semiconductor layer,
Micro LED assembly.
As a Micro-LED assembly,
A micro LED with a plurality of electrode parts stacked on one side; and
It includes a circuit board including a receiving portion in which the electrode portion is accommodated,
The electrode portion faces the circuit board and includes a first electrode and a second electrode formed in different shapes in at least one of height and width,
The circuit board includes a first accommodating part and a second accommodating part in which the first electrode and the second electrode are accommodated,
The first electrode is formed longer than the second electrode,
The first accommodating part is deeper than the second accommodating part,
The circuit board is
a first conductive layer laminated on one side facing the micro LED;
an insulating layer laminated on the first conductive layer; and
It includes a second conductive layer laminated on the insulating layer,
The first accommodating portion and the second accommodating portion are formed by forming a portion of the insulating layer and the second conductive layer through at least one of etching, drilling, etching, and laser processing.
Micro LED assembly.

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