KR20160131270A - Double-side tape and manufactureing method of light emitting device using the same - Google Patents

Abstract

Disclosed is a double-sided tape comprising a base layer; a foaming adhesive layer arranged on one surface of the base layer; and a UV-responsive adhesive layer arranged on the other side of the base layer. Also, disclosed is a manufacturing method of a light emitting device using the same. According to an embodiment of the present invention, the surface damage of the light emitting device can be prevented when removing a substrate.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided tape and a method of manufacturing a light-

The embodiment relates to a method of manufacturing a light emitting device using a double-sided tape.

A light emitting diode (LED) is one of light emitting devices that emits light when current is applied. Light emitting diodes can emit highly efficient light, thus saving energy.

The light emitting diode is applied to various devices such as a backlight unit of a liquid crystal display device, an electric sign board, a display device, and a home appliance.

The light emitting diode may have a structure in which an N-type electrode and a P-type electrode are disposed on one side of a light emitting structure including an N-type semiconductor layer, an active layer, and a P-type semiconductor layer.

The substrate of the light emitting diode can be removed as needed. Specifically, after a tape is attached and fixed to the opposite side of the substrate, the substrate can be irradiated with a laser to be removed. However, there is a problem that the light emitting structure is damaged during peeling of the tape.

One of the technical problems to be solved by the technical idea of the present invention is to prevent the light emitting device from being damaged in the substrate removing process.

A double-sided tape according to an embodiment of the present invention includes a base layer; A foamable adhesive layer disposed on one side of the base layer; And a UV reactive adhesive layer disposed on the other side of the base layer.

The heat-resistant temperature of the UV-sensitive adhesive layer may be higher than the foaming temperature of the foamable adhesive layer.

The heat-resistant temperature may be 20 ° C or more higher than the foaming temperature.

Wherein the base layer comprises: a first base layer on which the foamable adhesive layer is disposed; A second base layer on which the UV-reactive adhesive layer is disposed; And an adhesive layer disposed between the first base layer and the second base layer.

A method of manufacturing a light emitting device according to an embodiment of the present invention includes a base layer, a foamable adhesive layer disposed on one side of the base layer, and a double-sided tape including a UV reactive adhesive layer disposed on the other side of the base layer, Preparing; Attaching a light emitting element to one surface of the double-sided tape and attaching a dummy layer to the other surface of the double-sided tape; Removing the substrate of the light emitting device; Removing the dummy layer; And peeling the double-sided tape from the light emitting element.

The attaching step may attach the UV-reactive adhesive layer of the double-sided tape to the light emitting device chip, and attach the dummy layer to the foamable adhesive layer.

And irradiating the UV reactive adhesive layer with UV light between the step of removing the substrate and the step of removing the dummy layer.

According to the embodiment, the surface damage of the light emitting element can be prevented when the substrate is removed.

The various and advantageous advantages and effects of the present invention are not limited to the above description, and can be more easily understood in the course of describing a specific embodiment of the present invention.

1 is a conceptual view of a double-sided tape according to an embodiment of the present invention,
2 is a conceptual view of a double-sided tape according to another embodiment of the present invention,
3A to 3E are views for explaining a method of manufacturing a light emitting device according to an embodiment of the present invention,
4 is a conceptual diagram of a light emitting device according to an embodiment of the present invention,
5A and 5B are views for explaining a method of removing a substrate using a foam tape,
6 is an SEM photograph of the light emitting device from which the substrate is removed by the method of FIG.

The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated and described in the drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms including ordinal, such as second, first, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be referred to as a first component, and similarly, the first component may also be referred to as a second component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and redundant description thereof will be omitted.

1, a double-sided tape 10 according to an embodiment of the present invention includes a base layer 11, a foamable adhesive layer 13 disposed on one side of the base layer 11, and a base layer 11, Sensitive adhesive layer 12 disposed on the other side of the UV-sensitive adhesive layer 12.

The base layer 11 may serve to support the foamable adhesive layer 13 and the UV reactive adhesive layer 12. The base layer 11 may be made of a material that does not melt at the foaming temperature of the foam tape. As an example, the base layer 11 may be a polyimide film.

The foamable pressure-sensitive adhesive layer 13 may include various types of pressure-sensitive adhesives that foam at a predetermined temperature to lose adhesion. The foaming temperature may be about 100 ° C to 200 ° C. The foaming temperature is defined as the temperature at which the adhesive layer is foamed by heat and separated from the bonding surface. The thickness of the foamable pressure-sensitive adhesive layer 13 may be about 200 탆 to 400 탆, but is not limited thereto.

The UV-sensitive adhesive layer 12 may include various kinds of pressure-sensitive adhesives that lose adhesion when irradiated with ultraviolet light. The heat-resistant temperature of the UV-reactive pressure-sensitive adhesive layer 12 may be higher than the foaming temperature of the foamable pressure-sensitive adhesive layer 13. [

For example, the heat-resistant temperature of the UV-reactive adhesive layer 12 may be higher than the foaming temperature of the foamable pressure-sensitive adhesive layer 13 by about 20 ° C, but is not limited thereto. The heat-resistant temperature of the UV-reactive pressure-sensitive adhesive layer 12 is not limited as long as it is not meltable when a temperature at which the foamable pressure-sensitive adhesive layer 13 loses the adhesive force is applied. The thickness of the UV reactive adhesive layer 12 may be 20 탆 to 50 탆, but is not limited thereto.

2, the base layer 11 includes a first base layer 11B on which the foamable adhesive layer 13 is disposed, a second base layer 11A on which the UV reactive adhesive layer 12 is disposed, 1 adhesive layer 14 disposed between the first base layer 11B and the second base layer 11A.

The first base layer 11B may be a base material of a foam tape, and the second base layer 11A may be a base material of the UV reactive adhesive layer 12. [ That is, the foamable pressure-sensitive adhesive and the UV-reactive pressure-sensitive adhesive can be formed into a single double-sided tape by using an adhesive.

The total thickness of the double-sided tape 10 may be about 200 to 500 mu m. When the thickness is less than 200 탆, the performance of the foamable pressure sensitive adhesive layer and / or the UV reactive pressure sensitive adhesive layer is deteriorated. If the thickness exceeds 500 mu m, the tape may not be bent when being pulled by the vertical force, and the light emitting device 100 may be damaged.

3A to 3E are views for explaining a method of manufacturing a light emitting device according to an embodiment of the present invention.

3A to 3E, a method of manufacturing a light emitting device 100 according to an embodiment of the present invention includes the steps of preparing a double-sided tape 10, forming a light emitting device 100 on one surface of a double- Attaching a dummy layer (20) to the other surface, removing the substrate (180) of the light emitting device (100), irradiating the UV reactive adhesive layer (12) with UV light, (20), and peeling the double-sided tape (10) from the light emitting device (100).

Referring to FIG. 3A, in the attaching step, the light emitting device 100 and the dummy layer 20 are attached to both sides of the double-sided tape 10, respectively. Although the double-sided tape 10 is illustrated in the structure of FIG. 1, it may have the structure of FIG.

The light emitting device 100 includes a substrate 180, a light emitting structure 110 formed on the substrate 180, and pads 150 and 160 electrically connected to the light emitting structure 110, and pads 150 and 160 And a protective layer 170 disposed thereon. The light emitting device 100 may be a flip chip or a thin film flip chip (TFFC).

The pads 150 and 160 and the protective layer 170 of the light emitting element 100 are adhered to the UV reactive adhesive layer 12 of the double-sided tape 10 and the dummy layer 20 is adhered to the foamable adhesive layer 13 Can be adhered. The dummy layer 20 may be a fixing member for supporting the light emitting device 100 when the substrate 180 is removed.

Referring to FIG. 3B, removing the substrate 180 removes the substrate 180 of the light emitting device 100. The substrate 180 may be removed by a laser lift off (LLO) process. However, the present invention is not limited thereto, and the substrate 180 may be removed by a method such as mechanical polishing. That is, the method of removing the substrate 180 is not limited.

Referring to FIG. 3C, the step of irradiating UV irradiates the dummy layer 20 with UV light. The UV reactive adhesive layer 12 can substantially lose the adhesive force by UV irradiation. When heat is first applied to remove the dummy layer 20, the foaming surface of the foamable adhesive layer 13 becomes opaque and unevenness is formed by foaming. Therefore, there may arise a problem that it is difficult to inject sufficient UV into the UV reactive adhesive layer 12 because the foamable adhesive layer 13 reflects UV.

Referring to FIG. 3D, in the step of removing the dummy layer 20, the dummy layer 20 is peeled by applying a temperature equal to or higher than the foaming temperature. Since the dummy layer 20 is formed to have a thickness of about 0.7 mm to 2.0 mm in order to have a sufficient supporting force, it is difficult to peel off the double-sided tape 10 in a state where the dummy layer 20 is attached. Therefore, it is necessary to remove the double-sided tape 10 after peeling off the dummy layer 20 first. At a temperature of about 100 ° C to 200 ° C, the foamable pressure sensitive adhesive layer 13 is foamed to lose its adhesive strength.

Referring to FIG. 3E, the step of peeling the double-sided tape from the light emitting element can peel one end of the double-sided tape 10 in the vertical direction. At this time, the other surface (the surface where the substrate is separated) of the light emitting device 100 may also be fixed to the UV tape 30. The UV tape 30 can be removed by irradiating UV again.

Although one light emitting device has been described above, the light emitting device may be fabricated in a wafer level package form. That is, a plurality of light emitting devices may be fabricated on one wafer substrate and then separated. Therefore, a step of separating a plurality of light emitting elements may be further performed.

4 is a conceptual diagram of a light emitting device according to an embodiment of the present invention.

4, the light emitting device according to the present invention includes a light emitting structure 110 including a first semiconductor layer 111, an active layer 112, and a second semiconductor layer 113, a light emitting structure 110, First and second electrodes 130 and 140 and a first and second pads 150 and 160 electrically connected to the first and second electrodes 130 and 140 and a light- And a support layer 170 protecting the substrate 110.

According to the above-described process, the bottom surfaces of the first and second pads 150 and 160 and the supporting layer 170 are not damaged when the substrate is removed, and the yield can be improved.

The light emitting structure 110 includes a first semiconductor layer 111, an active layer 112, and a second semiconductor layer 113. The emission wavelength band of the light emitting structure 110 is not limited. For example, the light emitted from the light emitting structure may be an ultraviolet wavelength band, a visible wavelength band, or an infrared wavelength band. The components of each layer can be appropriately adjusted to produce light of the desired emission wavelength band.

The first semiconductor layer 111 may be formed of a compound semiconductor such as group III-V or II-VI, and the first semiconductor layer 111 may be doped with a first dopant. The first semiconductor layer 111 is a semiconductor material having a composition formula of AlxInyGa (1-xy) N (0? X? 1, 0? Y? 1, 0? X + y? 1), InAlGaN, AlGaAs, GaP, GaAs , GaAsP, and AlGaInP, but is not limited thereto. When the first dopant is an n-type dopant such as Si, Ge, Sn, Se, or Te, the first semiconductor layer 111 doped with the first dopant may be an n-type semiconductor layer.

Although the first semiconductor layer 111 is illustrated as a single layer in the drawing, the first semiconductor layer 111 may have a multi-layer structure. When the first semiconductor layer 111 has a multi-layer structure, the first semiconductor layer 111 may further include an unshown semiconductor layer (not shown). The un-doped semiconductor layer may be formed to improve the crystallinity of the first semiconductor layer 111 and may have a lower electrical conductivity than the first semiconductor layer 111 without being doped with the dopant.

The active layer 112 is a layer where electrons (or holes) injected through the first semiconductor layer 111 and holes (or electrons) injected through the second semiconductor layer 113 meet. The active layer 112 transitions to a low energy level as electrons and holes recombine, and generates light having a wavelength corresponding thereto.

The active layer 112 may have any one of a single well structure, a multiple well structure, a single quantum well structure, a multi quantum well (MQW) structure, a quantum dot structure, Is not limited thereto.

InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs (InGaAs) / AlGaAs, GaP (InGaP) / InGaN / InGaN / InGaN / InGaN / / AlGaP, but the present invention is not limited thereto. The well layer may be formed of a material having a band gap smaller than the band gap of the barrier layer.

The second semiconductor layer 113 may be formed of a compound semiconductor such as group III-V or II-VI, and the second semiconductor layer 113 may be doped with a second dopant. The second semiconductor layer 113 may be formed of a semiconductor material having a composition formula of InxAlyGa1-x-yN (0? X? 1, 0? Y? 1, 0? X + y? 1) or AlInN, AlGaAs, GaP, GaAs, GaAsP , AlGaInP, < / RTI > When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, or Ba, the second semiconductor layer 113 doped with the second dopant may be a p-type semiconductor layer.

The light emitting structure 100 includes a first semiconductor layer 111 which is an n-type semiconductor layer and a second semiconductor layer 113 which is a p-type semiconductor layer or a first semiconductor layer 111 which is a p- and a second semiconductor layer 113 which is an n-type semiconductor layer.

In addition, the light emitting structure 100 may have a structure in which an n-type or p-type semiconductor layer is further formed between the second semiconductor layer 113 and the active layer 112. That is, the light emitting structure 100 of the embodiment can be formed with at least any one of np, pn, npn, and pnp junction structures. The light emitting structure 100 of the embodiment includes the n-type semiconductor layer and the p- And the like.

The doping concentration of the impurities in the first semiconductor layer 111 and the second semiconductor layer 113 can be uniformly or nonuniformly formed. That is, the doping structure of the light emitting structure 100 may be variously formed, but is not limited thereto.

According to the embodiment, the upper surface of the light emitting structure 110 may have the concave and convex portions 111a, but is not limited thereto. For example, the upper surface of the first semiconductor layer 111 may be a flat surface.

The first electrode 130 and the second electrode 140 are disposed on one side of the light emitting structure 110. Here, one side may be opposite to the main emission surface of the light emitting structure 110.

The light emitting device according to the present invention may be a flip chip or a thin flip chip (TFFC) in which the first electrode 130 and the second electrode 140 are disposed on one side of the light emitting structure. However, the present invention is not limited thereto, and the first electrode 130 and the second electrode 140 may be arranged in parallel.

The structures arranged side by side are not necessarily limited to the structures arranged adjacent to each other at the same height. For example, if a step is formed on one side of the light emitting structure, the heights of the first electrode and the second electrode may be different.

The first electrode 130 may be electrically connected to the first semiconductor layer 111 and the second electrode 140 may be electrically connected to the second semiconductor layer 113.

The first electrode 130 may be electrically connected to the first semiconductor layer 111 through the ohmic electrode 131 and the second electrode 140 may be electrically connected to the second semiconductor layer 113 through the reflective electrode 114. [ And can be electrically connected. The extended portion of the first electrode 130 which is in contact with the ohmic electrode 131 is electrically insulated from the active layer 112 and the second semiconductor layer 113 by the protective film 115.

The first electrode 130 and the second electrode 140 may include a transparent conductive oxide film. The transparent conductive oxide film may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), aluminum gallium zinc oxide (AGZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (Indium Gallium Zinc Oxide), IGTO (Indium Gallium Tin Oxide), ATO (Antimony Tin Oxide), GZO (Gallium Zinc Oxide), IZON (IZO Nitride), ZnO, IrOx, RuOx and NiO.

The first electrode 130 and the second electrode 140 may be formed of an opaque metal such as Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au or Hf. The first electrode 130 and the second electrode 140 may be formed of one or a plurality of layers of a mixture of a transparent conductive oxide film and an opaque metal, but the present invention is not limited thereto.

The protective film 115 covers one side of the light emitting structure 100. The protective film 115 may include a light-transmitting or an opaque material. Shield 115 may be at least one selected from the group consisting of _{Si0 2, SixOy, Si 3 N} 4, SixNy, SiOxNy, Al 2 O 3, TiO 2, AlN or the like.

The support layer 170 may be composed of a resin to protect the light emitting structure 110 and the electrode.

FIG. 5 is a flow chart for explaining a method of removing a substrate using a foam tape, and FIG. 6 is an SEM photograph of a light emitting device from which a substrate is removed by the method of FIG.

The substrate 180 may be removed after attaching the dummy layer 2 to the light emitting device 100 on one side of the foam tape 1 and attaching the dummy layer 2 on the other side as shown in FIG. However, when the tape is separated by applying heat, a problem arises that scratches are generated in the light emitting device 100 during the separation process. Referring to FIG. 6, it is confirmed that the light emitting device is damaged (S) when only the foam tape is used.

10: Double-sided tape
11: base layer
12: UV reactive adhesive layer
13: foaming adhesive layer
20: Dummy layer
100: Light emitting element
110: light emitting structure
180: substrate

Claims (7)

A base layer;
A foamable adhesive layer disposed on one side of the base layer; And
And a UV reactive adhesive layer disposed on the other side of the base layer.
The method according to claim 1,
Wherein the heat-resistant temperature of the UV-reactive type pressure-sensitive adhesive layer is higher than the foaming temperature of the foamable pressure-sensitive adhesive layer.
3. The method of claim 2,
Wherein the heat-resistant temperature is at least 20 DEG C higher than the foaming temperature.
The method according to claim 1,
Wherein the base layer comprises:
A first base layer on which the foamable adhesive layer is disposed;
A second base layer on which the UV-reactive adhesive layer is disposed; And
And an adhesive layer disposed between the first base layer and the second base layer.
Preparing a double-sided tape including a base layer, a foamable adhesive layer disposed on one side of the base layer, and a UV reactive adhesive layer disposed on the other side of the base layer;
Attaching a light emitting element to one surface of the double-sided tape and attaching a dummy layer to the other surface of the double-sided tape;
Removing the substrate of the light emitting device;
Removing the dummy layer; And
And peeling the double-sided tape from the light emitting element.
6. The method of claim 5,
Wherein the attaching comprises:
Attaching the light emitting element to the UV reactive adhesive layer of the double-sided tape, and attaching the dummy layer to the foamable adhesive layer.
6. The method of claim 5,
Between the step of removing the substrate and the step of removing the dummy layer,
And irradiating the UV reactive adhesive layer with UV light.

Images