KR101803874B1 - Car lamp using semiconductor light emitting device and method for manufacturing - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle lamp, and more particularly to a vehicle lamp having a light source unit using a semiconductor light emitting element. The light source unit according to the present invention includes a base substrate, an electrode layer disposed on the base substrate, and a plurality of semiconductor light emitting elements electrically connected to the electrode layer, wherein the electrode layers are formed by overlapping the plurality of semiconductor light emitting elements And a common electrode surface, wherein at least a part of the common electrode surface is curved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a lamp for a vehicle using a semiconductor light emitting element,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lamp for a vehicle and a method of manufacturing the same, and more particularly to a lamp for a vehicle using a semiconductor light emitting element.

The vehicle is equipped with a variety of vehicle lamps having a lighting function or a signal function. Generally, a halogen lamp or a gas discharge lamp has been mainly used, but in recent years, a light emitting diode (LED) has attracted attention as a light source of a vehicle lamp.

Light emitting diodes (LEDs) are designed to minimize the size of LEDs and increase the design freedom of lamps. [0002] Light emitting diodes (LEDs) themselves, rather than packages, are semiconductor light emitting devices that convert current into light and are being developed as light sources for display images of electronic devices including information communication equipment.

However, since a vehicle lamp developed up to now uses a package type light emitting diode, the yield is low, the cost is high, and the degree of flexibility is weak.

Accordingly, a method of manufacturing a new type of vehicle lamp by manufacturing a flexible surface light source by using the semiconductor light emitting element itself, not the package, can be presented.

One object of the present invention is to realize a new type of vehicle lamp using a flexible planar light source.

Another object of the present invention is to realize a planar light source through a fine interval arrangement of semiconductor light emitting elements.

Another object of the present invention is to realize an insulating structure for eliminating a leakage current due to a defective semiconductor light emitting device.

The lamp includes a base substrate, an electrode layer disposed on the base substrate, and a plurality of semiconductor light emitting devices electrically connected to the electrode layer. The electrode layer has a common electrode surface on which the plurality of semiconductor light emitting devices overlap each other, and at least a part of the common electrode surface can be bent.

In an exemplary embodiment, the common electrode surface is formed to cover a space between the plurality of semiconductor light emitting elements so as to reflect light between the plurality of semiconductor light emitting elements. That is, the common electrode surface may have a structure of overlapping with the semiconductor light emitting elements along the up, down, left, and right directions. In addition, the common electrode surface may overlap 10 to 100,000 semiconductor light emitting devices.

In an embodiment, at least one groove may be formed in the electrode layer. And the groove may include a crack disposed at a curved portion of the common electrode surface.

In one embodiment, the electrode layer is a first electrode electrically connected to one of a p-type electrode and an n-type electrode of the semiconductor light emitting device, and the second electrode connected to the other of the p- Are formed in a line shape. The second electrode may be formed to extend along the bending line of the curved portion of the common electrode surface.

In an exemplary embodiment, an insulating layer is formed between the semiconductor light emitting elements, and the other of the p-type electrode and the n-type electrode extends from the semiconductor light emitting element to one surface of the insulating layer. At least one conductor that is not electrically connected to the semiconductor light emitting device may be disposed on one side of the insulating layer.

In an exemplary embodiment, the electrode layer may include a plurality of unit electrode layers, and the unit electrode layers may include unit common electrode surfaces each having a size corresponding to the plurality of semiconductor light emitting elements.

In the vehicle lamp according to the present invention, the process can be simplified through the electrode layer having the common electrode surface, high reflection can be performed in the electrode layer, and the light efficiency can be improved. Further, as the common electrode surface is bent, a surface light source that flexes flexibly to correspond to the three-dimensional shape of the lamp can be realized.

Further, by using the common electrode surface, current supply and voltage adjustment are easy, and additional structure such as a light guide is not required. In addition, the uneven supply of the current can prevent the decrease in the light uniformity that may occur in the large-area surface light source.

In addition, since a plurality of electrode layers are provided to realize a unit surface light source, it is possible to easily fabricate a large-area surface light source by assembling the unit surface light sources. Furthermore, as the electrode layer is divided into the unit electrode layers, the life of the product is improved and the repair can be facilitated.

Further, in the present invention, leakage current caused by the defective semiconductor light emitting element can be prevented by using an insulating layer having a flat surface. Further, by using the flat surface, the step of forming the insulation of the upper and lower electrodes can be implemented more simply.

1 is a conceptual diagram showing an embodiment of a lamp for a vehicle using the semiconductor light emitting element of the present invention.
Fig. 2 is a partially enlarged view of part A of Fig. 1, and Fig. 3 is a sectional view.
4 is a conceptual diagram showing a vertical semiconductor light emitting device of FIG.
FIGS. 5A, 5B, 5C, 5D, 5E, 5F and 5G are cross-sectional views illustrating a method of manufacturing a light source unit using the semiconductor light emitting device of the present invention.
6A to 6D are conceptual diagrams showing the design of a three-dimensional lamp.
Fig. 7 is an enlarged view of a portion A in Fig. 1 for explaining another embodiment of the present invention to which a semiconductor light emitting element having a new structure is applied.
FIG. 8 is a cross-sectional view taken along line BB of FIG. 7, FIG. 9 is a cross-sectional view taken along line CC of FIG. 7, and FIG. 10 is a conceptual view of a flip chip type semiconductor light emitting device of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. In addition, it should be noted that the attached drawings are only for easy understanding of the embodiments disclosed in the present specification, and should not be construed as limiting the technical idea disclosed in the present specification by the attached drawings.

It is also to be understood that when an element such as a layer, region or substrate is referred to as being present on another element "on," it is understood that it may be directly on the other element or there may be an intermediate element in between There will be.

The vehicle lamp described in this specification may include a headlamp, a tail lamp, a car light, a fog light, a turn signal lamp, a brake light, an emergency light, a tail lamp, and the like. However, it will be readily apparent to those skilled in the art that the configuration according to the embodiments described herein may be applied to a device capable of being displayed, even in the form of a new product to be developed in the future.

1 is a conceptual diagram showing an embodiment of a lamp for a vehicle using the semiconductor light emitting element of the present invention.

The vehicle lamp 10 according to an embodiment of the present invention includes a frame 11 fixed to a vehicle body and a light source unit 100 installed on the frame 11. [

A wiring line for supplying power to the light source unit 100 is connected to the frame 11, and the frame 11 can be fastened directly to the vehicle body or fixed via a bracket. According to the embodiment, a lens unit may be provided to further diffuse and brighten the light emitted from the light source unit 100.

The light source unit 100 may be a flexible light source which can be bent by an external force, bent, twistable, foldable, or curled.

In the state where the light source unit 100 is not bent (for example, a state having an infinite radius of curvature, hereinafter referred to as a first state), the light source unit 100 is flat. In the first state, the flexible light source part may be curved or curved at least partially in a state of being bent by an external force (for example, a state having a finite radius of curvature, hereinafter referred to as a second state).

The pixel of the light source unit 100 may be implemented by a semiconductor light emitting device. In the present invention, a light emitting diode (LED) is exemplified as one type of semiconductor light emitting device for converting a current into light. The light emitting diode is formed in a small size, so that it can serve as a pixel even in the second state.

Hereinafter, the light source unit implemented using the light emitting diode will be described in detail with reference to the drawings.

FIG. 2 is a partial enlarged view of part A of FIG. 1, FIG. 3 is a sectional view, and FIG. 4 is a conceptual view showing the vertical semiconductor light emitting device of FIG.

2, 3, and 4, a passive matrix (PM) semiconductor light emitting device is used as the light source unit 100 using the semiconductor light emitting device. However, the example described below is also applicable to an active matrix (AM) semiconductor light emitting device.

The light source unit 100 includes a base substrate 110, a first electrode 120, an adhesive layer 130, a second electrode 140, and a plurality of semiconductor light emitting devices 150.

The base substrate 110 may be a base layer on which a structure is formed through an entire process, and may be a wiring substrate on which the first electrode 120 is disposed. The base substrate 110 may include glass or polyimide (PI) to implement a flexible light source unit. Further, the base substrate 110 may be a thin metal. In addition, any insulating material such as PEN (polyethylene naphthalate) and PET (polyethylene terephthalate) may be used as long as it is insulating and flexible. In addition, the substrate 110 may be either a transparent material or an opaque material.

 Meanwhile, a heat radiation sheet, a heat sink, or the like may be mounted on the base substrate 110 to realize a heat radiation function. In this case, the heat dissipation sheet, the heat sink, or the like may be mounted on the opposite surface of the surface on which the first electrode 120 is disposed.

The first electrode 120 is disposed on the base substrate 110 and may be formed as a surface-shaped electrode. Accordingly, the first electrode 120 may be an electrode layer disposed on the base substrate, and may serve as a data electrode.

The adhesive layer 130 is formed on the base substrate 110 on which the first electrode 120 is located.

The adhesive layer 130 may be a layer having adhesiveness and conductivity. To this end, the adhesive layer 130 may be mixed with a substance having conductivity and a substance having adhesiveness. Thus, the adhesive layer may be referred to as a conductive adhesive layer. In addition, the adhesive layer 130 has ductility, thereby enabling a flexible function in the light source portion.

As an example, the adhesive layer 130 may be an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing conductive particles, or the like. The adhesive layer 130 may be configured as a layer having electrical insulation in the horizontal X-Y direction while allowing electrical interconnection in the Z direction penetrating through the thickness. Accordingly, the adhesive layer 130 may be referred to as a Z-axis conductive layer.

The anisotropic conductive film is a film in which an anisotropic conductive medium is mixed with an insulating base member. When heat and pressure are applied, only a specific part of the anisotropic conductive film has conductivity due to the anisotropic conductive medium. Hereinafter, the anisotropic conductive film is described as being subjected to heat and pressure, but other methods may be used to partially conduct the anisotropic conductive film. In this method, for example, either the heat or the pressure may be applied, or UV curing may be performed.

In addition, the anisotropic conduction medium can be, for example, a conductive ball or a conductive particle. According to the example, in the present example, the anisotropic conductive film is a film in which conductive balls are mixed with an insulating base member. When heat and pressure are applied, only specific portions are conductive by the conductive balls. The anisotropic conductive film may be a state in which a plurality of particles coated with an insulating film made of a polymer material are contained in the core of the conductive material. In this case, the insulating film is broken by heat and pressure, . At this time, the shape of the core may be deformed to form a layer in contact with each other in the thickness direction of the film. As a more specific example, heat and pressure are applied to the anisotropic conductive film as a whole, and the electrical connection in the Z-axis direction is partially formed by the height difference of the mating member adhered by the anisotropic conductive film.

As another example, the anisotropic conductive film may be in a state in which a plurality of particles coated with a conductive material are contained in the insulating core. In this case, the conductive material is deformed (pressed) to the portion where the heat and the pressure are applied, so that the conductive material becomes conductive in the thickness direction of the film. As another example, it is possible that the conductive material penetrates the insulating base member in the Z-axis direction and has conductivity in the thickness direction of the film. In this case, the conductive material may have a pointed end.

According to the present invention, the anisotropic conductive film may be a fixed array anisotropic conductive film (ACF) in which conductive balls are inserted into one surface of an insulating base member. More specifically, the insulating base member is formed of a material having adhesiveness, and the conductive ball is concentrated on the bottom portion of the insulating base member, and is deformed together with the conductive ball when heat and pressure are applied to the base member So that they have conductivity in the vertical direction.

However, the present invention is not limited thereto. The anisotropic conductive film may be formed by randomly mixing conductive balls into an insulating base member or by forming a plurality of layers in which a conductive ball is placed in a double- ACF) are all available.

The anisotropic conductive paste is a combination of a paste and a conductive ball, and may be a paste in which a conductive ball is mixed with an insulating and adhesive base material. In addition, solutions containing conductive particles can be solutions in the form of conductive particles or nanoparticles.

When the semiconductor light emitting device 150 is connected to the semiconductor light emitting device 150 by applying heat and pressure after the first electrode 120 is positioned on the base substrate 110, for example, after the anisotropic conductive film is positioned, 150 are electrically connected to the first electrode 120. In this case, the semiconductor light emitting device 150 may be disposed on the first electrode 120. In addition, since the anisotropic conductive film contains an adhesive component, the adhesive layer 130 realizes not only electrical connection but also mechanical bonding between the semiconductor light emitting device 150 and the first electrode 120.

As another example, the adhesive layer may include a tin-based alloy for eutectic bonding, Au, Al, or Pb, and the substrate and the semiconductor light emitting device may be bonded by Eutectic bonding.

Since the semiconductor light emitting device 150 has excellent brightness, individual unit pixels can be formed with a small size. The size of the individual semiconductor light emitting device 150 may be 80 mu m or less on one side and may be a rectangular or square device. In this case, the area of the single semiconductor light emitting device may be in the range of 10 ^-10 to 10 ^-5 m ² , and the distance between the light emitting devices may be in the range of 100 μm to 10 mm.

The semiconductor light emitting device 150 may have a vertical structure.

A plurality of second electrodes 140 are disposed between the vertical semiconductor light emitting devices and the plurality of second electrodes 140 are electrically connected to the semiconductor light emitting device 150.

4, the vertical semiconductor light emitting device includes a p-type electrode 156 formed on a p-type semiconductor layer 155, a p-type semiconductor layer 155 formed on a p-type electrode 156, an active layer 154 An n-type semiconductor layer 153 formed on the active layer 154; and an n-type electrode 152 formed on the n-type semiconductor layer 153. In this case, the p-type electrode 156 located at the lower portion may be electrically connected to the first electrode 120 by the adhesive layer 130, and the n-type electrode 152 located at the upper portion may be electrically connected to the second electrode 140, As shown in FIG. Since the vertical type semiconductor light emitting device 150 can arrange the electrodes up and down, it has a great advantage that the chip size can be reduced.

Referring again to FIGS. 2 and 3, the plurality of semiconductor light emitting devices 150 constitute a light emitting device array, and an insulating layer 160 is formed between the plurality of semiconductor light emitting devices 150 . For example, an insulating layer 160 is formed on one side of the adhesive layer 130 to fill a space between the semiconductor light emitting devices 150.

However, the present invention is not limited thereto, and the structure in which the adhesive layer 130 fills the space between the semiconductor light emitting elements without the insulating layer 160 is also possible.

The insulating layer 160 may be a transparent insulating layer including silicon oxide (SiOx) or the like. As another example, the insulating layer 160 may be formed of a polymer material such as epoxy, methyl, or phenyl-based silicone having a good insulation property and less light absorption, or an inorganic material such as SiN or Al2O3 Can be used.

According to the drawing, the phosphor layer 180 is formed on the light emitting element array.

The phosphor layer 180 may be formed on one surface of the semiconductor light emitting device 150. For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device 151 that emits blue (B) light, and a phosphor layer 180 for converting the blue (B) have. In this case, the phosphor layer 180 may be formed of a red phosphor capable of converting blue light into red (R) light, a green phosphor capable of converting blue light into green (G) light, And a yellow phosphor capable of being converted into a yellow phosphor.

In this case, the wavelength of the light formed in the Nitride-based semiconductor light emitting device is in the range of 390 to 550 nm and can be converted into 450 to 670 nm through the inserted film. Further, all of the red phosphor and the green phosphor can be provided, and light of various wavelengths can be mixed to realize white light. Also, when red light is required, a light diffusion film other than a phosphor may be used when a GaAs-based red semiconductor light emitting device is used. In addition, a patterned sheet can be inserted to improve light extraction efficiency.

In this case, an optical gap layer 171 may exist between the semiconductor light emitting device 150 and the phosphor layer 180. The optical gap layer 171 may be made of a material such as epoxy, acrylic, methyl, or phenyl-based silicone having low light absorption and excellent bending properties. In addition, a patterned sheet may be inserted to optimize light efficiency, or particles having different refractive indexes may be mixed.

At this time, the color filter 172 may be laminated on the phosphor layer 180 to improve the color purity of the converted light. In addition, the color filter 172 may be formed to cover the protective layer 173 to protect the light source portion from moisture, oxygen, and external impact. At this time, the protective layer 173 may be formed through film contact or resin coating.

Referring again to the present embodiment, the electrode layer (first electrode 120) has a common electrode surface 121 on which the plurality of semiconductor light emitting elements overlap, and at least a part of the common electrode surface 121 is bent Can be. That is, the first electrode 120 is implemented as a surface electrode and is driven as a common electrode.

The common electrode surface 121 covers between the plurality of semiconductor light emitting devices 150 so as to reflect light between the plurality of semiconductor light emitting devices 150, thereby realizing the structure of the high reflection electrode layer, .

The common electrode surface 121 may overlap 10 to 100,000 semiconductor light emitting devices, and the semiconductor light emitting device 150 may cover the common electrode surface 121 in an array form.

For example, the plurality of semiconductor light emitting devices 150 may have a matrix shape, and the common electrode surface 121 may overlap with the semiconductor light emitting device 150 along the up, down, left, and right directions. More specifically, the plurality of semiconductor light emitting devices 150 are arranged in rows and columns, and the common electrode surface 121 is formed such that a plurality of semiconductor light emitting devices 150 arranged along the rows and columns are overlapped with each other .

As another example, the semiconductor light emitting devices 150 may be irregularly arranged, and the common electrode surface 121 may cover all the irregularly arranged semiconductor light emitting devices 150.

As another example, the electrode layer may include a plurality of unit electrode layers, and the unit electrode layers (not shown) may have unit common electrode surfaces (not shown) each having a size corresponding to a plurality of semiconductor light emitting devices can do. The unit common electrode planes may be electrically connected to each other to easily realize a planar light source of a large area. In this case, it is possible to cope with various sizes and shapes of various structures in the structure, and the unit surface light source can be replaced, so that the product life and repair can be facilitated.

Since the first electrode 120 is formed as a surface electrode, the disconnection that may occur as the common electrode surface 121 is bent can be alleviated or prevented. More specifically, the light source portion may be attached to a curved or curved surface of the frame described above with reference to FIG. 1, so that the common electrode surface 121 may be at least partially curved. At this time, at least one groove 122 may be formed in the electrode layer. The groove 122 may include a crack disposed at a curved portion of the common electrode surface 121. As the groove is formed in the curved portion, even if the common electrode surface 121 is formed of metal, the force for elastic restoration is weakened, so that it can be more easily attached to the curved surface or the bent surface of the frame. In addition, even if the cracks are formed, the effect of preventing disconnection of the wiring can be exhibited because it is a surface electrode.

Alternatively, the second electrode 140 is located between the semiconductor light emitting devices 150 and is electrically connected to the semiconductor light emitting devices 150. For example, the semiconductor light emitting devices 150 may be disposed in a plurality of rows, and the second electrode 140 may be disposed between the columns of the semiconductor light emitting devices 150.

In this case, since the distance between the semiconductor light emitting elements 150 constituting the individual pixels is sufficiently large, the second electrode 140 can be positioned between the semiconductor light emitting elements 150.

In addition, the second electrode 140 may be formed as a long bar-shaped electrode in one direction. In this case, the second electrode 140 may be formed to extend along the bending line BL of the curved portion of the common electrode surface 121. For example, the second electrode 140 may be formed in parallel with the bending line BL. In this case, the second electrode 140 may not be bent in a line shape, so that wiring failure does not occur. In other words, minimization of electrode stress and prevention of cracks can be exerted through n wiring electrodes parallel to the bending line BL.

The second electrode 140 and the semiconductor light emitting device 150 may be electrically connected to each other by a connection electrode protruded from the second electrode 140. More specifically, the connection electrode may be an n-type electrode 152 of the semiconductor light emitting device 150. For example, the n-type electrode 152 is formed as an ohmic electrode for ohmic contact, and the second electrode 140 covers at least a part of the ohmic electrode by printing or vapor deposition. The second electrode 140 and the n-type electrode 152 of the semiconductor light emitting device 150 can be electrically connected to each other.

According to the example, the second electrode 140 may be positioned on the insulating layer 160. In the case where the adhesive layer 130 fills the space between the semiconductor light emitting devices without the insulating layer 160, the second electrode 140 may be bonded to the adhesive layer 130, Lt; / RTI >

The second electrode 140 may be formed integrally with the n-type electrode 152 and the n-type electrode 152 may extend from the semiconductor light emitting element to one side of the insulating layer 160 . However, the present invention is not limited thereto, and the second electrode 140 may be formed integrally with the p-type electrode 156. That is, the electrode layer (first electrode) described above is an electrode electrically connected to any one of the p-type electrode 156 and the n-type electrode 152 of the semiconductor light emitting device, and the p- The other one of the electrodes 152 may extend from one side of the insulating layer 160 in the semiconductor light emitting device.

Hereinafter, the second electrode 140 is formed integrally with the n-type electrode 152, and the second electrode 140 and the n-type electrode 152 are referred to as a second electrode 140 . The second electrode 140 is formed in a line shape and extends to one surface of the insulating layer 160 in a direction perpendicular to the extending direction of the line in the semiconductor light emitting device.

For the implementation of the structure, the insulating layer 160 may include a first plane 161 covering the electrode layer and a hole formed on the opposite side of the first plane 161 and exposing the semiconductor light emitting device to the outside And may have a second plane 162. In order to extend the second electrode 140 to the second plane 162, the second plane 162 may be formed on the same plane as the n-type semiconductor layer 153 of the semiconductor light emitting device.

As a more specific example, the second plane 162 may be a flat surface without protruding portions, which may be realized by the planarization process described later. In reality, the second plane 162 may have a step with the outer surface of the semiconductor light emitting device, but may be flattened to 90 to 95% of the step.

According to the structure, at least one conductor 141 that is not electrically connected to the semiconductor light emitting device may be disposed on one side of the insulating layer 160. The conductor 141 may be formed at a position where the semiconductor light emitting device is not present when the second electrode 140 is deposited. Accordingly, the conductor 141 may be formed of the same material as the other one of the p-type electrode 156 and the n-type electrode 152. For example, the conductor 141 is formed of the same material as the second electrode 140 integrated with the n-type electrode 152, as shown in this example. In addition, since the second electrode 140 is formed during deposition, the second electrode 140 has the same thickness as the second electrode 140.

The insulating layer 160 may be formed to fill the gap between the conductor 141 and the electrode layer so as to restrict a short circuit between the conductor 141 and the electrode layer. At this time, the insulating layer 160 may be completely filled between the conductor 141 and the first electrode 120. Therefore, a structure in which the conductor and the first electrode 120 are not short-circuited is realized. If the planarization process is not performed, hole processing is required through etching or the like in order to connect the second electrode 140 to the second conductive type semiconductor layer. If a hole is formed in the place where the semiconductor light emitting device is not formed by the hole processing, a short circuit problem may occur between the second electrode and the first electrode, but this problem can be prevented in this structure.

Hereinafter, a method of manufacturing the light source unit including the planarization process will be described in detail with reference to the drawings.

FIGS. 5A, 5B, 5C, 5D, 5E, 5F and 5G are cross-sectional views illustrating a method of manufacturing a light source unit using the semiconductor light emitting device according to the present invention, and FIGS. 6A to 6E illustrate a three- These are conceptual diagrams.

First, according to the manufacturing method, a step of joining a plurality of semiconductor light emitting elements to a substrate proceeds. For example, the n-type semiconductor layer 153, the active layer 154, and the p-type semiconductor layer 155 are grown on the growth substrate and the p-type electrode 156 is formed after each semiconductor light- (Fig. 5A).

The growth substrate 101 (wafer) may be formed of any material having light transmission properties, for example, sapphire (Al 2 O 3), GaN, ZnO, or AlO, but is not limited thereto. Further, the growth substrate 101 may be formed of a carrier wafer, which is a material suitable for semiconductor material growth. And may include a conductive substrate or an insulating substrate, for example, a SiC substrate having higher thermal conductivity than a sapphire (Al2O3) substrate, or at least one of Si, GaAs, GaP, InP and Ga2O3 Can be used.

For example, each of the semiconductor light emitting devices having a thickness (D) of 5 to 10 um may be arranged on a growth plate in the form of a two-dimensional array with a pitch of 20 to 150 um and a pitch (P) of 200 to 1000 um.

In this case, an undoped semiconductor layer 153a may be formed on the other surface of the n-type semiconductor layer 153.

Next, the semiconductor light emitting device is bonded to the wiring substrate using the adhesive layer 130, and the growth substrate is removed (FIG. 5B).

The wiring board refers to a substrate in which a first electrode 120, that is, a surface electrode is formed, and the first electrode 120 is a lower wiring and a first electrode 120 is formed on a base substrate. The wiring board is electrically connected to the p-type electrode 156 in the adhesive layer 130 by a conductive ball or the like.

At this time, the wiring substrate and the growth substrate 101 are thermally bonded. For example, the wiring board and the growth substrate 101 can be thermocompression-bonded using an ACF press head. The wiring substrate and the growth substrate 101 are bonded by the thermocompression bonding. Only the portion between the semiconductor light emitting device 150 and the first electrode 120 has conductivity due to the characteristic of the anisotropic conductive film having conductivity by thermocompression bonding so that the first electrode 120 and the semiconductor light emitting device 150 may be electrically connected to each other. At this time, the semiconductor light emitting device 150 can be inserted into the anisotropic conductive film.

Then, the growth substrate 101 is removed. For example, the growth substrate 101 can be removed using a laser lift-off method (LLO) or a chemical lift-off method (CLO).

In particular, the undoped semiconductor layer 153a protects the semiconductor light emitting device when the growth substrate 101 is removed by a laser lift-off method (LLO). However, the present invention is not necessarily limited to this, and the undoped semiconductor layer may be replaced with another type of absorption layer that absorbs the UV laser. The absorption layer may be a buffer layer, may be formed in a low-temperature atmosphere, and may be made of a material capable of alleviating the difference in lattice constant between the semiconductor layer and the growth substrate. For example, materials such as GaN, InN, AlN, AlInN, InGaN, AlGaN, and InAlGaN.

At this time, the semiconductor light emitting devices may be partially transferred from the growth substrate to the wiring substrate through the selective transfer technique. A method may be used in which a part of the semiconductor light emitting device is transferred from the growth substrate to the carrier substrate and then the semiconductor light emitting device is transferred from the carrier substrate to the wiring substrate for selective transfer.

Thereafter, a relatively high-viscosity resin is coated on the wiring board on which the semiconductor light emitting device is mounted by a spin coating method, and then a first planarization insulating film having high transparency characteristics is formed through heat treatment (FIG. 5C). In this case, the first planarization insulating film 160a may be hardened by heat treatment.

For example, a high-viscosity resin is spin-coated on a semiconductor light emitting device arranged on a transferred substrate, and heat treatment is performed using a hotplate at 90 to 100 ° C to remove a solvent component contained in the resin. The thickness of the resin at the time of spin coating is spin-coated to a thickness of about 70 to 80% of the step difference in consideration of a step between the light emitting element and the light emitting element. In this case, when calculating the flatness (%) = 1- (H / D), the flatness can be secured to 70 to 80% of the initial step. At this time, the resin remaining on the upper part of the semiconductor light emitting device includes a thickness of 1 um or more, and the resin is wrapped in contact with the surface of the semiconductor light emitting device.

In this case, when the resin is applied, a failure occurs in the selective transfer, so that the resin is filled in the portion where the semiconductor light emitting element is not adhered properly.

Next, the wiring substrate is laminated using a roller at a temperature at which thermal fluidity is secured to form a final planarization film 160b (FIG. 5D). For example, the resin is planarized by the Roll-Lamination process at a temperature of 100 to 150 ° C to form an isolation layer having a flatness of 90% or more. As an example of this, the substrate is irradiated with ultraviolet light or photo-cured, or thermally cured at a temperature of 100 to 150 ° C to form inter-electrode isolation.

More specifically, the surface of the substrate may be covered with the high heat-resistant release film and the Si-based rubber sheet, and the lamination may proceed at a low speed in a lamination rubber heated to 100 to 150 ° C. securing thermal fluidity. After laminating, leave the film at room temperature for 5 to 10 minutes and remove the film on the surface.

Thereafter, the entire surface of the substrate is irradiated with an energy of 500 to 800 mJ using an ultraviolet exposure machine, and the resin is thermally cured at 150 to 200 ° C. Through this process, the thickness of the resin located on the top of the semiconductor light emitting device can be 1um or less, and the level difference (flatness) between the top surface and the other surface of the semiconductor light emitting device can be 90 to 95% have. With the above-described method, high flatness without defects on the surface can be ensured.

After the planarizing film is formed, the resin is etched to expose one side of the semiconductor light emitting device to the outside (FIG. 5E). For example, the resin is anisotropically selectively dry etched to remove the resin on the top of the semiconductor light emitting device.

More specifically, the thermosetting resin is subjected to plasma etching using a gas such as O 2 or O 2 + SF 6. Thus, the surface of the semiconductor light emitting device under the resin, that is, the undoped semiconductor layer 153a, is exposed to the outside.

Next, the step of removing the undoped semiconductor layer 153a of the semiconductor light emitting element proceeds (FIG. 5F).

For example, an undoped semiconductor layer exposed outside is etched using a gas such as Cl 2 + BCl 3 to etch an undoped semiconductor layer, and an n-type semiconductor layer 153 ) Is exposed to the outside.

At this time, a defect occurs in the selective transfer and the flattening film continues to exist even in the portion where the semiconductor light emitting element is not adhered properly.

Thereafter, an n-type electrode 152 is deposited on the n-type semiconductor layer 153 to form a wiring (FIG. 5G). The n-type electrode 152 may extend from the semiconductor light emitting device to one side of the insulating layer 160 through the deposition.

As described above, the n-type electrode 152 may be formed integrally with the second electrode 140 (see Fig. 3), and may be formed in a line shape. The n-type electrode 152 may be formed to be perpendicular to the extending direction of the line And extends to one side of the insulating layer 160 in the direction of FIG.

When the n-type electrode 152 is deposited after the planarization process, a conductor of the same material as that of the n-type electrode 152 can be formed at a portion where the semiconductor light emitting element is not adhered properly. However, Is insulated from the first electrode by the insulating layer 160, so that shorting between the n-type electrode and the p-type electrode does not occur.

Thereafter, the optical gap layer, the phosphor layer, the color filter, and the protective layer may be laminated in order. The light source unit implemented by the above process may be bent or bent to correspond to the shape of the frame of the vehicle lamp and mounted on the frame. The common electrode surface of the first electrode which is a surface electrode can be bent at least partly by the warping or bending. Therefore, the design of the three-dimensional lamp as shown in Figs. 6A to 6E becomes possible.

In the display device using the semiconductor light emitting device of the present invention described above, when the flip chip type is applied, since the first and second electrodes are disposed on the same plane, it is difficult to realize a fixed pitch (fine pitch). Hereinafter, a display device to which such a flip chip type light emitting device according to another embodiment of the present invention can be solved will be described.

FIG. 7 is an enlarged view of a portion A in FIG. 1 for explaining another embodiment of the present invention to which a semiconductor light emitting device having a new structure is applied, FIG. 8 is a sectional view taken along line BB in FIG. 7, 7, and FIG. 10 is a conceptual diagram showing the flip-chip type semiconductor light emitting device of FIG.

The light source unit 1000 includes a base substrate 1010, a first electrode 1020, an adhesive layer 1030, a second electrode 1040, and a plurality of semiconductor light emitting devices 1050. Here, the first electrode 1020 and the second electrode 1040 may each include a plurality of electrode lines.

The base substrate 1010 is a wiring substrate on which the first electrode 1020 is disposed, and may include polyimide (PI) to implement a flexible display device. In addition, any insulating and flexible material may be used.

The first electrode 1020 is disposed on the substrate 1010 and may be formed as a surface-shaped electrode. Accordingly, the first electrode 120 may be an electrode layer disposed on the base substrate, and may serve as a data electrode.

An adhesive layer 1030 is formed on the substrate 1010 where the first electrode 1020 is located. The adhesive layer 1030 may be an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing conductive particles, or the like, as in the light source portion to which the above-described vertical type semiconductor light emitting device is applied .

As another example, the adhesive layer 1030 may include a tin-based alloy for eutectic bonding, Au, Al, or Pb, and the substrate and the semiconductor light emitting device may be bonded by Eutectic bonding.

A plurality of second electrodes 1040, which are formed in a line shape and electrically connected to the semiconductor light emitting device 1050, are positioned between the semiconductor light emitting devices 1050.

According to the illustration, the second electrode 1040 may be positioned on the insulating layer 1060. That is, the insulating layer 1060 is disposed between the wiring substrate and the second electrode 1040. For example, an insulating layer 1060 is formed on one side of the adhesive layer to fill a space between the semiconductor light emitting devices 1050. However, the present invention is not limited thereto, and the structure in which the adhesive layer 1030 fills the space between the semiconductor light emitting elements without the insulating layer 1060 is also possible.

The insulating layer 1060 may be a transparent insulating layer 1060 including silicon oxide (SiOx) or the like. As another example, the insulating layer 1060 may be formed of a polymer material such as epoxy, methyl, or phenyl-based silicone having excellent insulation characteristics and less light absorption, or an inorganic material such as SiN or Al2O3, Can be used.

The light emitting device array may include an optical gap layer 1071, a fluorescent layer 1080, a color filter 1072, and a protective layer 1073. The structure of the optical gap layer 1071, the phosphor layer 1080, the color filter 1072, and the protective layer 1073 in the array is the same as the structure of the light source section described above with reference to FIGS. 2 and 3, I will replace the above.

Referring again to the electrode layer, the first electrode 1020 has a common electrode surface on which the plurality of semiconductor light emitting devices 1050 overlap, and at least a part of the common electrode surface can be bent. That is, the first electrode 1020 is implemented as a surface electrode and is driven as a common electrode. The structure of the common electrode surface is the same as the structure of the light source unit described above with reference to FIGS. 2 and 3, and thus the description thereof is omitted.

In the semiconductor light emitting device 1050 of this example, the semiconductor light emitting device 1050 is disposed at the upper side and the lower side, but the semiconductor light emitting device of the present invention is a flip chip type light emitting device .

10, for example, the semiconductor light emitting device 1050 includes a p-type electrode 1156, a p-type semiconductor layer 1155 on which a p-type electrode 1156 is formed, and a p-type semiconductor layer 1155 An n-type semiconductor layer 1153 formed on the active layer 1154 and an n-type electrode 1152 formed on the n-type semiconductor layer 1153. The active layer 1154 is formed on the active layer 1154,

In this case, the n-type electrode is disposed on one surface of the n-type semiconductor layer 1153, and an undoped semiconductor layer 1153a may be formed on the other surface of the n-type semiconductor layer 1153 .

The p-type electrode 1156 and the n-type electrode 1152 have a height difference from each other in the width direction and the vertical direction (or thickness direction) at positions spaced apart along the width direction of the semiconductor light emitting element 1050 .

The n-type electrode 1152 is formed on the n-type semiconductor layer 1153 by using the height difference but is disposed adjacent to the second electrode 1040 located on the semiconductor light emitting device 1050. For example, at least a portion of the n-type electrode 1152 protrudes from the side of the n-type semiconductor layer 1153 (or the side of the undoped semiconductor layer 1153a) along the width direction . Thus, since the n-type electrode 1152 protrudes from the side surface, the n-type electrode 1152 can be exposed to the upper side of the semiconductor light emitting element 1050. Accordingly, the n-type electrode 1152 is disposed at a position overlapping the second electrode 1040 disposed on the conductive adhesive layer 1030.

More specifically, the semiconductor light emitting element 1050 is extended from the n-type electrode 1152 and has protrusions 1152a protruding from the sides of the plurality of semiconductor light emitting elements. In this case, the p-type electrode 1156 and the n-type electrode 1152 are disposed at positions spaced apart along the protruding direction of the protruding portion 1152a with respect to the protruding portion 1152a, Can be expressed as being formed to have a height difference with respect to each other in a vertical direction.

The protrusion 1152a extends laterally from one surface of the n-type semiconductor layer 1153 and is formed on the upper surface of the n-type semiconductor layer 1153, more specifically, an undoped semiconductor layer 1153a . The protrusion 1152a protrudes along the width direction from the side of the undoped semiconductor layer 1153a. Therefore, the protrusion 1152a may be electrically connected to the second electrode 1040 on the opposite side of the p-type electrode with respect to the n-type semiconductor layer.

The structure including the protrusions 1152a may be a structure that can take advantage of the above-described horizontal semiconductor light emitting device and vertical semiconductor light emitting device.

The second electrode 1040 may be electrically connected to the n-type electrode 1052 and the second electrode 140 may extend from the semiconductor light emitting device to one side of the insulating layer 1060 have. However, the present invention is not limited thereto, and the second electrode 1040 may be formed integrally with the n-type electrode 1052.

The second electrode 140 is formed in a line shape and extends to one surface of the insulating layer 1060 in a direction perpendicular to the extending direction of the line in the semiconductor light emitting device.

According to the structure, at least one conductor 1041 that is not electrically connected to the semiconductor light emitting device 1050 may be disposed on one surface of the insulating layer 1060. The conductor 1041 may be formed at a position where the semiconductor light emitting device is not present when the second electrode 1040 is deposited. The insulating layer 1060 may fill the gap between the conductor 1041 and the first electrode 1020. Accordingly, a structure in which the conductor 1041 and the first electrode 1020 are not short-circuited is realized.

According to the structure described above, a light source unit using a flip chip type semiconductor light emitting device can be realized.

The above-described display device using the semiconductor light emitting device is not limited to the configuration and the method of the embodiments described above, but all or a part of the embodiments may be selectively combined so that various modifications may be made to the embodiments It is possible.

Claims (15)

1. A vehicle lamp having a light source portion for emitting light,
The light source unit includes:
A base substrate;
An electrode layer disposed on the base substrate; And
And a plurality of semiconductor light emitting elements electrically connected to the electrode layer,
Wherein the electrode layer has a common electrode surface on which the plurality of semiconductor light emitting elements overlap each other, at least a part of the common electrode surface is bent,
Wherein the common electrode surface covers between the plurality of semiconductor light emitting elements so as to reflect light between the plurality of semiconductor light emitting elements. delete The method according to claim 1,
Wherein the common electrode surface overlaps 10 to 100000 semiconductor light emitting elements. The method according to claim 1,
Wherein at least one groove is formed in the electrode layer. 5. The method of claim 4,
Wherein the groove has a crack disposed in a curved portion of the common electrode surface. The method according to claim 1,
Wherein the plurality of semiconductor light emitting elements are arranged in rows and columns,
Wherein the common electrode surface is formed such that a plurality of semiconductor light emitting elements arranged along the rows and the columns overlap each other. The method according to claim 1,
Wherein the electrode layer is a first electrode electrically connected to one of a p-type electrode and an n-type electrode of the semiconductor light emitting device,
And the second electrode connected to the other one of the p-type electrode and the n-type electrode is formed in a line shape. 8. The method of claim 7,
And the second electrode is formed to extend along a bending line of the curved portion of the common electrode surface. 8. The method of claim 7,
An insulating layer is formed between the semiconductor light emitting elements,
And the other of the p-type electrode and the n-type electrode extends from the semiconductor light emitting element to one surface of the insulating layer. 10. The method of claim 9,
Wherein at least one conductor that is not electrically connected to the semiconductor light emitting device is disposed on one surface of the insulating layer. 11. The method of claim 10,
Wherein the insulating layer is formed so as to fill a space between the conductor and the electrode layer so as to restrict a short between the conductor and the electrode layer. 11. The method of claim 10,
And the conductor is made of the same material as the other one of the p-type electrode and the n-type electrode. 10. The method of claim 9,
Wherein the insulating layer has a first plane covering the electrode layer and a second plane formed on an opposite side of the first plane and including holes through which the semiconductor light emitting device is exposed to the outside. 14. The method of claim 13,
Wherein the second plane is a flat surface without protruding portions. The method according to claim 1,
Wherein the electrode layer includes a plurality of unit electrode layers,
Wherein the unit electrode layers each have unit common electrode surfaces formed to have sizes corresponding to the plurality of semiconductor light emitting elements.

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