KR102474502B1 - Sheet lighting and manufacturing method of the same - Google Patents

Abstract

The present invention relates to sheet lighting and a manufacturing method thereof.
The present invention provides a sheet light manufactured by attaching micro-sized vertical light emitting diodes formed in a separate semiconductor process to a target substrate on which a seating electrode is formed and a method for manufacturing the same.
The sheet lighting according to the present invention can be used as a three-dimensional surface light source, has a low driving voltage, reduces the risk of electric shock, and is light in weight, making it possible to provide lighting that does not require a separate complicated installation structure.

Description

Sheet lighting and its manufacturing method {SHEET LIGHTING AND MANUFACTURING METHOD OF THE SAME}

The present invention relates to a sheet light and a method for manufacturing the same, and more particularly, to a sheet light using a micro-sized vertical light emitting diode (VLED) and a method for manufacturing the same.

Compound semiconductor light-emitting devices that convert electrical signals into light using the characteristics of compound semiconductors, that is, light-emitting devices such as LED (Light Emitting Diode) or Laser Diode (LD), are used in lighting, optical communication, and multiple communication applications. It is a trend that is being researched and put to practical use in

In general, light emitting devices are grown or deposited in a vertical structure on a substrate. In particular, a light emitting device having a structure in which an insulator sapphire substrate is used and a semiconductor layer in different regions as a semiconductor light emitting layer and an active layer, which is an active region, are deposited thereon, all electrodes are formed on the upper part of the device and combined by a flip chip or wire bonding method, or a bonding metal layer It constitutes a vertical light emitting diode combined with a conductive wafer substrate.

Cross-sectional views shown in FIGS. 1 to 5 show a conventional method of manufacturing a vertical light emitting diode step by step. First, in FIG. 1, a buffer layer 103 is formed on a sapphire substrate 100, an n-type semiconductor layer 105 made of gallium nitride (GaN)-based semiconductor, an active layer 107, and p made of gallium nitride (GaN)-based semiconductor. The mold semiconductor layer 109 is sequentially formed. Thereafter, a trench portion 115 is formed through etching so that the light emitting structure has an individual device region, and a p-type electrode 111 and a reflective film are formed on the p-type semiconductor layer 109 (FIG. 2). In FIG. 2, a protective thin film layer 113 is formed on the side of the light emitting structure using an insulator material such as SiO2 or Si3N4. In the case of the protective thin film layer 113, it is possible to improve the electrical characteristics of the device by blocking the flow of current to the side of the light emitting structure.

A conductive substrate 120 such as silicon (Si), gallium arsenide (GaAs), or silicon carbide (SiC) is bonded or deposited on the p-type electrode and the reflective film 109 (FIG. 3). Thereafter, the sapphire substrate 100 is lifted off using a laser, and etching is performed to expose the surface of the n-type semiconductor layer 105 on the surface of the removed sapphire substrate (FIG. 4). Next, when an n-type electrode (not shown) is formed on the n-type semiconductor layer 105 and separated into individual chips, a plurality of vertical light emitting diodes 150 as shown in FIG. 5 are simultaneously obtained.

In the above description, the process of forming a so-called n-top light emitting diode having an n-type electrode formed thereon has been described, and it goes without saying that a p-top light emitting diode in contrast thereto can be easily formed through a similar process.

6 is a cross-sectional view of an LED light emitting device using a conventional vertical light emitting diode. The LED light emitting device 190 includes a substrate 157 on which a cavity 159 is formed, and a p-type connection electrode 151 and an n-type connection electrode 153 are formed on the bottom surface of the cavity 159, The conductive substrate 120 of the vertical light emitting diode 150 is bonded so that the p-type connection electrode 151 is in contact with each other, and the n-type electrode is bonded to the n-type connection electrode 153 using a bonding wire 161, When the cavity 159 is filled with a conventional transparent resin 155, the LED light emitting element 190 is formed.

The LED light emitting device 190 configured as described above has a longer lifespan and excellent luminous efficiency than gas lamps including conventional fluorescent lamps that emit light using gas, and is gradually replacing gas lamps. However, since this LED light emitting element 190 is mounted on a hard substrate and has a considerable thickness, there is a limit to use it in a three-dimensional shape or various shapes.

Republic of Korea Patent Publication No. 2007-0079957 (2007.08.08. Publication) Republic of Korea Patent Publication No. 2013-0069351 (2013.06.26. Publication)

The present invention is to solve the above limitations, and to provide a sheet lighting using vertical light emitting diodes having a size of several to hundreds of microns and a manufacturing method thereof.

The above object of the present invention is to manufacture a target substrate having a plurality of seating electrodes provided to be electrically spaced apart from each other and a plurality of horizontal electrodes electrically connecting the neighboring seating electrodes, attached to the seating electrode, and the target substrate At least one micro-vertical light emitting diode manufactured by a process separate from the p-type electrode and having a height between the n-type electrode and the p-type electrode of several hundred micrometers or less, and located at the top of the p-type electrode and the n-type electrode of the vertical light emitting diode It is possible to achieve by sheet lighting, characterized in that it comprises a first transparent electrode layer in contact with the electrode and an insulating layer laminated between the connection electrode and the first transparent electrode layer.

Another object of the present invention is a first step of preparing a target substrate having a plurality of seating electrodes provided to be electrically spaced apart from each other and a plurality of horizontal electrodes electrically connecting the adjacent seating electrodes, and a p-type electrode A second step of manufacturing micro vertical light emitting diodes having a height between the n-type electrodes of several hundred micrometers or less, and a third step of seating at least one micro vertical light emitting diode manufactured in the second step on each seating electrode; , Forming a first insulating layer covering the horizontal connection electrode, the seating electrode, and the micro-vertical light emitting diode, and exposing the upper electrode among the p-type electrode or the n-type electrode constituting the micro-vertical light emitting diode. A fourth step of forming a layer and a fifth step of forming a first transparent conductive layer deposited on the first insulating layer, characterized in that the first step and the second step are performed regardless of order. It is possible to achieve by the sheet lighting manufacturing method to.

Another object of the present invention is a step a of preparing a target substrate having a plurality of seating electrodes provided to be electrically spaced apart from each other and a plurality of horizontal electrodes electrically connecting the adjacent seating electrodes, and an upper portion of the connecting electrode The b-th step of forming a first insulating layer, the c-th step of manufacturing a micro-vertical light emitting diode having a height between the p-type electrode and the n-type electrode of several hundred micrometers or less, and the micro-vertical light-emitting diode manufactured in the c-th step. A d step of seating at least one type light emitting diode on each of the seating electrodes, and an e step of forming a first insulating layer and a first transparent conductive layer on top of the micro vertical type light emitting diode, It is achievable by a sheet lighting manufacturing method characterized in that it is performed regardless of any step and sequence of the step before step c.

The sheet lighting manufactured according to the present invention has a total thickness of 25 μm or more and can be configured to be less than several mm, and can be formed on a flexible substrate, so that three-dimensional lighting can be manufactured and can be cut into various shapes and used. Therefore, from the point of view of lighting design, it is possible to produce three-dimensional lighting in various shapes with freedom in design.

The sheet lighting according to the present invention has the advantage of being able to be formed to have a bezel of 1 mm or less in contrast to LED lighting and OLED lighting using a conventional light guide plate when a quantum dot sheet or a phosphor sheet is not used.

The seat lighting of the present invention can be formed of a transparent material except for the horizontal connection electrode or the seating electrode, and since the area occupied by the horizontal connection electrode or the seating electrode is small among the total parts of the lighting, it can be formed by transmission lighting. In addition, when the vertical type light emitting diode provided on the seating electrode is used with both the p-top and n-top mounted, it can be used as double-sided lighting.

The seat lighting according to the present invention has a small weight per unit area compared to conventional lighting, and thus has the advantage of being easily installed on a ceiling or the like without a separate complicated structure. When using a PI (PolyImid) substrate as a target substrate, there is an advantage in that the entire lighting can be configured such that the weight per unit area increases by approximately 20% compared to the PI substrate.

In addition, since the sheet lighting according to the present invention is configured with a simple structure using conventionally known vertical light emitting diodes, the manufacturing cost can be kept low, so that it can be used universally as a sheet lighting, contributing to popularization. Finally, since the seat lighting according to the present invention uses a micro light emitting diode driven at a low voltage, it is possible to maintain a low overall driving voltage, so that it is possible to manufacture lighting free from electric shock due to driving.

1 to 5 are manufacturing process diagrams of a conventional vertical type light emitting diode.
6 is a cross-sectional view of an LED light emitting device using a conventional vertical light emitting diode.
7 to 10 are process diagrams illustrating a process of manufacturing a vertical light emitting diode according to an embodiment of the present invention and transferring it to a transfer substrate.
11 is a partial perspective view of a seat light of an embodiment according to the present invention viewed from a planar direction and a cross-sectional view of a vertical light emitting diode of an embodiment according to the present invention.
12 is a cross-sectional view of a seat lighting according to an embodiment of the present invention.
13 is a cross-sectional view of a seat lighting according to an embodiment of the present invention.
14 is a cross-sectional view of a seat lighting according to an embodiment of the present invention.
15 to 19 are cross-sectional views of a manufacturing process of a seat lighting according to an embodiment of the present invention.
20 is a manufacturing process diagram of the present invention explaining the process of irradiating a laser on the upper surface of the transfer substrate.
21 is a cross-sectional view of another embodiment of a seat light according to the present invention.
22 is a cross-sectional view of another embodiment of a seat light according to the present invention.
23 to 25 are manufacturing process diagrams of the seat lighting shown in FIG. 21 .

Terms used in the present invention are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Also, in the present specification, "on ~ or ~ on top" means located above or below the target part, and does not necessarily mean located on the upper side relative to the direction of gravity. Further, when a part such as a region, plate, etc. is said to be "on or over" another part, this is not only when it is in contact with or spaced "directly on or above" the other part, but also when another part is in the middle thereof. Including if there is

In addition, in this specification, when one component is referred to as “connected” or “connected” to another component, the one component may be directly connected or directly connected to the other component, but in particular Unless otherwise described, it should be understood that they may be connected or connected via another component in the middle.

Also, in this specification, terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another.

Hereinafter, preferred embodiments, advantages and characteristics of the present invention will be described in detail with reference to the accompanying drawings.

First, a vertical type light emitting diode formation process will be described. Some processes are similar to manufacturing processes of conventional vertical type light emitting diodes. As shown in FIG. 1, a buffer layer 103 on a sapphire substrate 100, an n-type semiconductor layer 105 made of gallium nitride (GaN)-based semiconductor, an active layer 107, and a gallium nitride (GaN)-based semiconductor The p-type semiconductor layer 109 is sequentially formed. Thereafter, a trench portion 115 is formed through etching so that the light emitting structure has an individual device region, and a p-type electrode 111 is formed on the p-type semiconductor layer 109 (similar to FIG. 2). The vertical light emitting diode according to the present invention is structurally different from conventional vertical light emitting diodes in that the p-type electrode 111 is formed using a conductive transparent electrode and no reflective film is formed. As shown in FIG. 2, the vertical light emitting diode according to the present invention forms a protective thin film layer 113 on the side of the light emitting structure using an insulator material such as SiO2 or Si3N4. Such a protective thin film layer 113 may be omitted since it is not necessarily provided in the vertical type light emitting diode of the present invention.

Prepare a transfer substrate 200 coated with a separation layer 210 on one surface, and contact the separation layer 210 on top of a vertical diode grown on a sapphire substrate 100 as shown in FIG. 7). The separation layer 210 is composed of an adhesive material or an adhesive material, and is formed of an organic material having peelability while expanding by absorbing laser when irradiated with laser. Representative materials for forming the separation layer 210 include a photoresist forming material and polyimide.

The sapphire substrate 100 is lifted off by irradiating an excimer laser in the same manner as in the prior art (FIG. 8). Thereafter, the separation layer 210 not in contact with the vertical light emitting diode is removed (FIG. 9). Partial removal of the separation layer 210 may be performed using O2 plasma, wet etching, or a reactive ion etcher (RIE) process.

An n-type electrode 117 is patterned on the n-type semiconductor layer 105 exposed after the sapphire substrate 100 is lifted off. In this case, the n-type electrode 117 may be formed of an opaque conductive electrode and a reflective layer together if it is not necessary to manufacture a transparent sheet light or a bidirectional light emitting sheet light. It goes without saying that the processes performed in FIGS. 9 and 10 may be performed in any order.

11 is a partial perspective view of a seat light of an embodiment according to the present invention viewed from a planar direction and a cross-sectional view of a vertical light emitting diode of an embodiment according to the present invention. FIG. 11(a) shows a seat light, and FIG. 11(b) shows a cross-section of a vertical light emitting diode 160 of the present invention mounted on a seat light. In practice, when viewing the sheet lighting from a plane, the internal electrodes or the vertical type light emitting diode of the present invention may not be visible, but FIG. 11 shows them for convenience of description.

Seat lighting 300 according to the present invention is composed of a seating electrode 310 having a uniform interval and composed of a repetitive pattern, and a horizontal connection electrode 350 functioning as a wire electrically connecting the seating electrode 310 to each other. It consists of It is characterized in that at least one vertical light emitting diode 160 of the present invention is provided on each seating electrode 310 . In FIG. 11 (a), it can be seen that one to three vertical light emitting diodes 160 of the present invention are provided in the individual seating electrodes 310.

The total height (thickness) of the completed sheet lighting can be produced in various heights by adjusting the thickness of the first insulating layer, the first transparent electrode layer, and the second transparent electrode layer, and can be formed to be approximately 25 μm or more and several mm or less. .

11(b) shows a cross-sectional view of the vertical type light emitting diode 160 of the present invention. On the n-type electrode 117, an n-type semiconductor layer 105, an active layer 107, a p-type semiconductor layer 109, and a p-type electrode 111 are provided. Optionally, a protective film layer 113 may be further formed to minimize the current flow in the horizontal direction. The vertical light emitting diode 160 of the present invention uses a micro LED having a height of several to hundreds of microns, and sheet lighting can be formed using the vertical light emitting diode having such a height.

The seat lighting of the present invention has the following geometrical characteristics, which have not been presented in the prior art.

Geometrical Characteristics 1 :

The diameter of the seating electrode should be larger than the diameter of the die (n-type electrode) of the vertical light emitting diode 160 . Here, the die diameter of the vertical light emitting diode 160 means the largest diameter of the area occupied when the vertical light emitting diode 160 is normally seated on the seating electrode 310 . In the present invention, at least one vertical light emitting diode 160 should be mounted on one seating electrode. More preferably, at least two or more vertical light emitting diodes 160 are mounted on one seating electrode. The reason for this is to allow the remaining vertical light emitting diodes 160 to emit light even if one vertical light emitting diode 160 fails and does not operate.

Geometrical Characteristic 2 :

The width of the horizontal connection electrode should be smaller than the die diameter of the vertical light emitting diode. This configuration prevents light emission when the vertical light emitting diode 160 is seated on the horizontal connection electrode 350 .

Geometrical Characteristic 3 :

The separation distance between the centers of adjacent seating electrodes should be greater than the vertical distance from the top of the second conductive layer to the upper surface of the vertical light emitting diode normally seated on the seating electrode. This is a limitation on the basic structure constituting the surface light source. The distance between the centers of adjacent seating electrodes is indicated by 'P' in FIG. 11 . The vertical distance from the top of the second conductive layer to the top of the vertical light emitting diode normally seated on the seating electrode is indicated by 'v' in FIG. 12 .

FIG. 12 is a cross-sectional view in the direction A-A' of FIG. 11 . The seating electrode 310 and the horizontal connection electrode 350 are formed on the target substrate 301, and the vertical light emitting diode 160 of the present invention is formed on the seating electrode 310 so that only the p-type electrode 111 is exposed. 1 is provided while being surrounded by the insulating layer 302. A first transparent electrode layer 303 and a second transparent electrode layer 305 are sequentially stacked on the first insulating layer 302 .

The first transparent electrode layer 303 is formed of a material in which a transparent polymer material having adhesion or adhesive properties and a conductive material are mixed. Examples of the conductive material include conductive nanoparticles, nanowires, nanometal wires, conductive organic materials, carbon nanotubes, carbon black, graphene, and metal grid wires. The first transparent electrode layer 303 may be formed if the material has conductivity and is mixed with a polymer to have adhesion or adhesive properties. The first transparent electrode layer 303 may be formed to a desired thickness d1 using an appropriate deposition process. A typical range for the thickness d1 of the first transparent electrode layer 303 is several μm to may be several millimeters.

The second transparent electrode layer 305 may also be formed to a desired thickness d2 using a similar material and method. A typical range for the thickness d2 of the second transparent electrode layer 305 may be several μm to several mm. The first transparent electrode layer 303 and the second transparent electrode layer 305 may be made of ITO or other transparent conductive films. As will be described later, the sheet lighting of the present invention does not need to include both the first transparent electrode layer 303 and the second transparent electrode layer 305, and may be formed with only one transparent electrode layer. Other suitable deposition processes for the first transparent electrode layer 303 and the second transparent electrode layer 305 include chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), and evaporation. , and plasma spray.

A light conversion layer 307 is formed on top of the second transparent electrode layer 305 . If the micro vertical type light emitting diode 160 radiates one monochromatic light to the seating electrode 310, the sheet illumination can emit only one monochromatic light. In this configuration, a light conversion layer 307 may be provided to implement white color or other colors. The light conversion layer 307 is a layer that converts monochromatic light incident from below into another monochromatic light or multi-color light and outputs the light, and may be implemented with a quantum dot, phosphor, or color filter. A diffusion sheet may be provided on the light conversion layer 307 . Window paper may be used as the diffusion sheet.

The target substrate 301 may be implemented with glass, metal foil, fabric, a flexible synthetic resin substrate, a printed circuit board (PCB), or a flexible printed circuit board (FPCB). When a PCB or FPCB is used as the target substrate 301, the seating electrode 310 and the horizontal connection electrode 350 can be pattern-printed, so a separate forming process is not required. However, when a high-temperature process is required to laminate the first insulating layer 302, the first transparent electrode layer 303, and the second transparent electrode layer 305, the target substrate 301 must be used as a heat-resistant substrate, and the heat-resistant substrate As an example of the resin to be formed, it is of course possible to implement using polyimide or the like.

13 is a cross-sectional view of a seat lighting according to an embodiment of the present invention. The difference from the sheet lighting shown in FIG. 12 is a cross-sectional view of a sheet lighting in which a vertical light emitting diode 160 without using a protective thin film layer 113 is used and a horizontal connection electrode 350 is formed of two conductive materials. it did In FIG. 13 , the protective thin film layer 113 is removed by forming the vertical light emitting diode 160 to surround the outside with the first insulating layer. In addition, FIG. 13 shows an example formed of a horizontal connection electrode 350 composed of first horizontal connection electrodes 350a provided on both sides and a second horizontal connection electrode 350b interconnecting them in the middle.

14 is a cross-sectional view of a seat lighting according to an embodiment of the present invention. The difference from the sheet lighting shown in FIG. 13 is that (1) the color conversion layer 307 and the diffusion sheet 309 are removed and a transparent protective film 311 is laminated, and (2) the top of the first transparent electrode layer 303. The process of forming the second transparent electrode layer, which was provided in , was omitted, and (3) the horizontal connection electrode 350 was formed as two horizontal connection electrodes formed in two layers. In the structure shown in FIG. 14, in forming the horizontal connection electrode 350, the first horizontal connection electrode 350a is formed so that the central portion of the lower layer is separated, and the second insulating layer 304 is formed therebetween. , A structure for forming the second horizontal connection electrode 350b interconnecting the first horizontal connection electrode 350a on the second insulating layer 304 is suggested.

As shown in FIG. 14 , the composition of the film (thin film) stacked on the second transparent metal layer 305 may be implemented in various combinations as needed. For example, in the case of constructing sheet lighting using three primary color (R, G, and B) light emitting diodes, the color conversion layer 307 is unnecessary and can be omitted, of course. In addition, of course, a protective film having damage prevention and heat dissipation functions may be laminated as the outermost layer constituting the sheet lighting.

Hereinafter, a process for manufacturing a seat light according to the present invention will be described. 15 to 19 are cross-sectional views illustrating a process of manufacturing a target substrate according to the present invention. According to the process shown in FIGS. 8 to 10, the transfer substrate 200 to which the vertical light emitting diode 160 is attached is positioned on the upper side, and the target substrate having the seating electrode 310 and the horizontal connection electrode 350 on the lower side. 301 is prepared (FIG. 15). The seating electrode 310 and the horizontal connection electrode 350 provided on the target substrate 301 may be formed as transparent or opaque electrodes, if necessary. Thereafter, the laser 500 is irradiated to the vertical light emitting diode 160 positioned above the seating electrode 310 . The laser 500 is irradiated from the top of the transfer substrate 200 to which the vertical light emitting diodes 160 are attached, and the separation layer 210 absorbs energy emitted from the laser and expands, and the vertical light emitting diodes attached thereto ( 160) is separated and placed on the seating electrode 310 (FIG. 16).

Preferably, the irradiated laser 500 is preferably irradiated only to the separation layer 210 located at the boundary between the vertical light emitting diode 160 and the transfer substrate 200, but it is irradiated to the surroundings without accurately irradiating the corresponding location. case will happen. 20 is a view for explaining a case where the focus is not coincided in laser irradiation. (A) is a cross-sectional view of a case in which three vertical light emitting diodes 160 are attached to the transfer substrate 200 and the laser 200 is irradiated from the top of the transfer substrate 200, (B) The drawing (A) shows the drawing in a planar state. (B) In the drawing, the solid line circles 210a, 210b, and 210c show the separation layers 210a, 210b, and 210c interposed between the respective vertical light emitting diodes 160 and the transfer substrate 200, and the broken lines The circles 500a, 500b, and 500c in show the irradiated laser light source. As shown in (a), when the laser light source 500a is precisely focused on the separation layer 210a, the n-type electrode 117 is normally seated on the surface of the seating electrode while the vertical light emitting diode attached thereto vertically descends. Chances are high. In contrast, as shown in (b) or (c), when the laser beams 500b and 500c are not accurately focused on the separation layers 210b and 210c, and the focusing is misaligned to the left or right, the vertical light emission attached thereto The diode may reach the seating electrode in a tilted state without descending in the vertical direction. To solve this problem, the n-type electrode 117 is formed to be heavier than other elements, and the distance between the n-type electrode 117 and the separation layer 210 is kept as narrow as possible in the state of FIG. 15 .

In addition, unlike FIG. 10, as shown in FIG. 9, when the separation layer 210 not in contact with the vertical light emitting diode is not removed, the separation layer 210 is scattered by the laser and the vertical light emitting diode It was confirmed that it stuck to the electrode to be seated and caused a defect. In particular, this problem mainly occurred when the laser was not accurately focused on the separation layer, as shown in (b) and (c) of FIG. 20 . Therefore, as shown in FIG. 9 , the separation layer 210 in the remaining area not in contact with the vertical light emitting diode should be removed.

Again, the manufacturing process of the lighting sheet will be described. As shown in FIG. 17, in a state where the vertical light emitting diode 160 is seated, a first insulating layer 302 is deposited on the seating electrode 310, the horizontal connection electrode 350, and the vertical light emitting diode 160. and forming the first insulating layer 302 until the p-type electrode portion is exposed. As the first insulating layer 302, a negative photosensitive insulating film was used. When the first insulating layer 302 is formed as a negative photosensitive insulating film, light is irradiated from the lower surface of the target substrate 301 so that the first insulating layer 302 can be exposed in a self-aligned manner so that only the p-type electrode portion is exposed. do.

Representative examples of the negative photosensitive resin composition forming the negative photosensitive insulating film include 5 to 40 parts by weight of a binder resin, 2 to 50 parts by weight of a multifunctional monomer having an ethylenically unsaturated bond, 0.005 to 20 parts by weight of a photoinitiator, and an epoxy group or an amine group. Contains 0.0001 to 3 parts by weight of a silicon-based compound (Korean Patent Publication No. 2005-0071885). Another negative photosensitive resin composition includes (1) a copolymer of a carboxyl group-containing unsaturated monomer and another unsaturated monomer copolymerizable with the monomer, (2) a polymerizable unsaturated compound, and (3) a photopolymerization initiator represented by the following formula (1) A composition containing may be used (Korean Patent Publication No. 2013-0110439).

Although the process of forming the first insulating layer 302 with an N-type photosensitive insulating film material has been described, the first insulating layer 302 can be formed with a P-type photosensitive insulating film material.

A P-type photosensitive insulating film is formed by exposing a P-type photosensitive resin, and examples of the P-type photosensitive resin include an alkali-soluble resin and a 1,2-quinonediazide compound.

Thereafter, the first transparent electrode layer 303 and the second transparent electrode layer 305 are sequentially laminated (FIGS. 18 and 19), and the necessary thin film layer is laminated on top of the second transparent metal layer 305, as shown in FIGS. 12 and 13 Alternatively, the seat lighting of FIG. 14 is completed.

While the inventor of the present invention manufactures and uses the seat lighting shown in FIG. 14, some vertical light emitting diodes constituting the seat lighting are broken due to static electricity (ESD: Electro Static Discharge), etc., and a significant leakage current occurs in the broken diode. Occasionally, a phenomenon that could not be used as a seat lighting occurred. Therefore, in the present invention, it is necessary to cut off the power supplied to the corresponding seating electrode (to be precise, the malfunctioning vertical light emitting diode) when excessive current is generated due to such static electricity. This problem could be solved in two ways. A first method is to form the first transparent electrode layer 303 with a thin metal having a low melting point. A typical example of a metal with a low melting point is a metal that forms a fuse. Heat is generated when excessive current flows through the failed diode, and the generated heat melts the first transparent electrode layer 303 at the top. Therefore, it is preferable to form the first transparent electrode layer 303 thinner than the second transparent electrode layer 305 and to form a material with a low melting point. The second method is to form the horizontal connection electrode 350 with a metal with a low melting point. Since the horizontal connection electrode 350 is generally formed as an opaque electrode, a material forming a fuse may be used as it is. A similar principle is to block the current flowing to the seating electrode 310 where the faulty vertical light emitting diode is located. As shown in FIG. 13 or 14, when the horizontal connection electrode 350 is formed with the first horizontal connection electrode 350a and the second horizontal connection electrode 350b to form a seat light, the second horizontal connection electrode 350b It is preferable to form a material that forms a fuse. That is, in this case, the material forming the second horizontal connection electrode 350b should be implemented with a material having greater resistance than the material forming the first horizontal connection electrode 350a.

In the sheet lighting of the present invention, when the film or the like stacked on the target substrate and the second transparent metal layer is formed transparently, it can be formed to look transparent even when the switch is not turned on. In this case, it is better to implement the seating electrode and the horizontal connection electrode with a transparent material. In the case of such transparent sheet lighting, when at least one layer (film) stacked on the second transparent metal layer is formed as a semi-reflective layer, bi-directional lighting that emits light to both upper and lower surfaces can be used.

21 is a cross-sectional view of another embodiment of a seat light according to the present invention. A seating electrode 310 and a horizontal connection electrode 350 are formed on a target substrate 301, and a first insulating layer 302 is formed on top of the horizontal connection electrode 350 so that the seating electrode 310 is exposed. , At least one vertical light emitting diode 160 of the present invention is provided above the seating electrode 310, and the first insulating layer 302 and the first transparent electrode layer 303 are stacked on top of the vertical light emitting diode 160, , A protective film 311 is provided on the first transparent electrode layer 303 . The seat lighting shown in FIG. 21 has a configuration in which the space 320 between the seating electrode 310 and the first transparent electrode layer 303 is emptied into an empty space. Of course, the interspace 320 may be filled with a separate third insulating material if necessary. It can be seen that in the sheet lighting shown in FIG. 21 , the height of the top of the vertical light emitting diode 160 seated on the seating electrode 310 is higher than that of the top of the first insulating layer 302 . In this case, the first transparent conductive layer 303 is preferably formed of a transparent conductive layer having elasticity. Specifically, an adhesive or adhesive material that provides elasticity to the polymer forming the transparent conductive layer may be used.

22 is a cross-sectional view of another embodiment of a seat light according to the present invention. Compared to the structure of the seat lighting shown in FIG. 22, the seat lighting shown in FIG. 21, the uppermost height of the vertical light emitting diode 160 seated on the seating electrode 310 is lower than the top of the first insulating layer 302. There is a difference in one point.

The sheet lighting shown in FIG. 21 or 22 may further include a second transparent conductive layer as described above, and various combinations of films stacked on top of the transparent conductive layer are of course possible. The sheet lighting shown in FIG. 21 or 22 may be formed by forming the target substrate and the protective film 311 in a separate process and then combining them. This process will be briefly described using FIGS. 23 to 25 .

As shown in FIG. 23, the seating electrode 310 and the horizontal connection electrode 350 are formed on the top of the target substrate 200, and the first insulating layer 302 is deposited so that only the top of the seating electrode 310 is exposed. molded after Next, at least one vertical light emitting diode 160 is provided on the seating electrode 310 (FIG. 24). A protective film 311 is prepared in a process separate from that of FIGS. 23 and 24, and a first transparent conductive layer 303 is formed thereon (FIG. 25). Then, when the protective film and the target substrate shown in FIGS. 24 and 25 formed by each separate process are bonded together, the manufacturing of the sheet lighting is completed.

It has been described that the sheet lighting shown in FIGS. 21 and 22 can be manufactured by a bonding process. Of course, the sheet lighting shown in FIGS. 21 and 22 can be formed by sequentially stacking the first transparent conductive layer 303 and the protective film 311 thereon after completing the process shown in FIG. 24 instead of forming by the bonding process. Of course there is.

In the description so far, the sheet lighting of the present invention has been described as a structure implemented using a p-top vertical light emitting diode. Of course, the sheet lighting of the present invention can be implemented using n-top vertical light emitting diodes.

In addition, as shown in FIGS. 12 and 13 , the vertical type light emitting diode seated on the seating electrode does not necessarily need to be formed such that the n-type electrode contacts the seating electrode. For example, a total of 5 micro-vertical light emitting diodes are placed on one seating electrode, 2 out of 5 have n-type electrodes in contact with the seating electrode, and the remaining 3 have p-type electrodes in contact with the seating electrode. It is free to do In this case, it is also possible to implement double-sided light-emitting sheet lighting in which upward and downward irradiation are sequentially turned on in a time-division manner. Such double-sided light-emitting sheet lighting can be implemented in a driving method in which + and - potentials are alternately radiated to both electrodes in a time-division manner, and can be easily implemented in a PWM driving method.

Although the preferred embodiments of the present invention have been described and illustrated using specific terms above, such terms are only used to clearly explain the present invention, and the embodiments and described terms of the present invention are the technical spirit and scope of the following claims. It is obvious that various changes and changes can be made without departing from the above. Such modified embodiments should not be individually understood from the spirit and scope of the present invention, and should be said to fall within the scope of the claims of the present invention.

100: sapphire substrate 103: buffer layer
105: n-type semiconductor layer 107: active layer
109: p-type semiconductor layer 111: p-type electrode
113: protective film layer
115: trench portion 117: n-type electrode
150: conventional vertical light emitting diode 151: p-type connection electrode
153: n-type connection electrode 155: transparent resin
157 substrate 159 cavity
160: vertical type light emitting diode of the present invention
161: bonding wire 190: LED light emitting element
200: transfer substrate 210, 210a, 210b, 210c: separation layer
300: seat lighting 301: target substrate
302: first insulating layer 303: first transparent electrode layer
304: second insulating layer 305: second transparent electrode layer
310: seating electrode
350: horizontal connection electrode 350a: first horizontal connection electrode
350b: second horizontal connection electrode 500, 500a, 500b, 500c: laser light

Claims (5)

A sheet light manufactured by transferring the micro vertical light emitting diode from a transfer substrate to which one of the p-type electrode and the n-type electrode of the micro vertical light emitting diode is attached,
A target substrate having a plurality of seating electrodes formed to be electrically spaced apart from each other and a plurality of horizontal connection electrodes electrically connecting the adjacent seating electrodes;
- One of the p-type electrode and the n-type electrode of the micro vertical type light emitting diode attached to the transfer substrate is adhered to the transfer substrate through a separation layer patterned as much as the area of the one electrode -
- The same potential is applied to the plurality of seating electrodes by the horizontal connection electrode -
The micro vertical type light emitting diode fixedly installed on the seating electrode;
- The micro vertical light emitting diode is manufactured by a process separate from the manufacturing of the target substrate, and the height between the p-type electrode and the n-type electrode is less than several hundred micrometers -
A transparent electrode layer formed to contact the remaining electrodes not attached to the seating electrode among the p-type electrode and the n-type electrode of the micro-vertical light emitting diode, and
Including an insulating layer laminated between the horizontal connection electrode and the transparent electrode layer,
Seat lighting, characterized in that when viewed from a plane, the seating electrode is provided with an area in which two or more micro-vertical light emitting diodes can be seated.
According to claim 1,
An upper surface of the seating electrode is formed higher than an upper surface of the horizontal connection electrode, and a width of the horizontal connection electrode when viewed from a plane is smaller than a die diameter of the micro vertical light emitting diode.
- The die diameter of the micro vertical light emitting diode means the maximum diameter measured in the area where the micro vertical light emitting diode is seated on the seating electrode -
Seat lighting characterized by.
According to claim 1,
Sheet lighting, characterized in that the horizontal distance (p) between the centers of the adjacent seating electrode is formed larger than the height (v) of the transparent electrode layer.
According to claim 3,
The horizontal connection electrode is formed of a first horizontal connection electrode formed to contact the seating electrode and a second horizontal connection electrode formed to contact the adjacent first horizontal connection electrode, and the second horizontal connection electrode is formed to be in contact with the first horizontal connection electrode. 1 sheet lighting, characterized in that formed of a material having a greater resistance than the horizontal connection electrode.
According to claim 1,
Sheet lighting, characterized in that the separation layer is made of an adhesive material or adhesive material.

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