KR20170022349A - light emitting device package - Google Patents

Abstract

An embodiment relates to a light emitting device package which forms shapes of a cavity and a light emitting device arranged in the cavity to be similar to each other to improve light efficiency. According to an embodiment of the present invention, the light emitting device package comprises: a body including a cavity having a circular upper surface; and a polygonal light emitting device arranged in the cavity, and having an upper surface surrounded with at least six lines.

Description

A light emitting device package

The embodiment relates to a light emitting device package with improved light efficiency.

A light emitting diode (LED) is one of light emitting devices that emits light when current is applied. Light emitting diodes are capable of emitting light with high efficiency at low voltage, thus saving energy. In recent years, the problem of luminance of a light emitting diode has been greatly improved, and it has been applied to various devices such as a backlight unit of a liquid crystal display device, a display 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 N-type electrode and the P-type electrode are electrically connected to the N-type pad and the P-type pad, respectively. The N-type pad and the P-type pad can be connected to the lead frame or mounted on a printed circuit board by using the bonding layer.

The light emitting diode may be used as a light source for a display, a light source for a vehicle, and a light source for an illumination, and a light emitting diode package that emits white light using a light emitting diode and a phosphor may be formed. At this time, the light emitting diode may be electrically connected to the first and second lead frames disposed in the package body and separated through the electrode separation region by a wire bonding method.

A typical light emitting device package includes a body including a cavity and a light emitting element disposed in the cavity. Then, the molding member is filled in the cavity so as to cover the light emitting element.

However, a general light emitting device package has a large deviation in the distance between the side surface of the light emitting device and the inner side surface of the body, and may cause total reflection of light in a region where the distance between the side surface of the light emitting device and the inner surface of the body is narrow. That is, when light is emitted from the light emitting device package, a color deviation may occur depending on the directional angle, and the quality of the light emitting device package may be deteriorated.

Embodiments provide a light emitting device package capable of improving the light efficiency by changing the shape of the light emitting device.

The light emitting device package of the embodiment includes a body including a cavity whose top surface is circular; And a polygonal light emitting element disposed in the cavity, the upper surface of which is surrounded by at least six line segments.

A light emitting device package according to another embodiment includes a body including a cavity whose top surface is circular; And a light emitting element disposed in the cavity and having a top surface in a circular shape, wherein a distance between a side surface of the light emitting element and an inner surface of the body is all the same.

A light emitting device package according to another embodiment includes a body including a cavity having a polygonal shape whose upper surface is surrounded by at least six line segments; And a light emitting element which is disposed in the cavity and whose upper surface is the same polygon as the cavity.

In the case where the cavity and the light emitting device are hexagons surrounded by n (n is a natural number of 6 or more) line segments on the upper surface, a vertex of a selected one of n vertices of the upper surface of the light emitting device and n vertexes At one point of the imaginary n connection lines connecting the closest vertices of the two.

The light emitting device package of the embodiment of the present invention has the following effects.

First, when the upper surface of the cavity is circular, the upper surface of the light emitting device disposed in the cavity is surrounded by at least six line segments, so that the uniformity of the gap between the side surface of the light emitting device and the inner surface of the body can be improved.

Secondly, since the shapes of the light emitting element and the cavity are the same, the uniformity of the gap between the side surface of the light emitting element and the inner surface of the body can be improved.

1A is a plan view of a light emitting device package of an embodiment of the present invention.
1B is a cross-sectional view taken along line I-I 'of FIG. 1A.
2 is a cross-sectional view of the light emitting device of FIG.
3 is a plan view of a light emitting device package including a light emitting device having a square top surface.
4A and 4B are plan views of a light emitting device package according to another embodiment of the present invention.
5A to 5D are plan views of a light emitting device package according to another embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the embodiments of the present invention are not intended to be limited to the specific embodiments but include all modifications, equivalents, and alternatives falling within the spirit and scope of the embodiments.

Terms including ordinals, such as first, second, 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 embodiments, 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 herein is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of 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.

In the description of the embodiments, in the case where one element is described as being formed "on or under" another element, the upper (upper) or lower (lower) or under are all such that two elements are in direct contact with each other or one or more other elements are indirectly formed between the two elements. Also, when expressed as "on or under", it may include not only an upward direction but also a downward direction with respect to one element.

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.

Hereinafter, the light emitting device package of the embodiment will be described in detail with reference to the accompanying drawings.

1A is a plan view of a light emitting device package according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line I-I 'of FIG. 1A. 2 is a cross-sectional view of the light emitting device of FIG. 1A.

1A, 1B, and 2, the light emitting device package of the embodiment includes a body 100 including a cavity 100a, a light emitting device 140 disposed in the cavity 100a, a light emitting device 140, Is electrically connected to the electrode member 120 disposed under the cavity. Although the light emitting device 140 is connected to the electrode member 120 through wires in the drawing, when the light emitting device 140 is a chip scale package, the electrode of the light emitting device 140 is directly connected to the electrode member 120 .

The body 100 may be formed of one or more materials selected from the group consisting of silicon, silicon carbide (SiC), aluminum nitride (AlN), polyphthalamide (PPA), epoxy molding compound (Liquid Crystal Polymer), and the like. However, the present invention is not limited thereto. The body 100 may be formed by a method such as injection or etching.

When the body 100 is formed of a conductive material, an insulating film (not shown) is further formed on the inner surface of the body 100 to prevent the body 100 from being electrically connected to the light emitting device 140 . Although the top edge of the body 100 is shown as being square in the figure, the top edge of the body 100 may be polygonal, or may be circular with a curved or curved surface.

A reflective member (not shown) may be formed on the inner surface of the body 100 to reflect light emitted from the light emitting device 140, thereby improving the efficiency of light emitted to the outside of the light emitting device package. In this case, the reflective member (not shown) may be formed by coating a reflective material on the inner surface of the body 100, or the reflective body may be formed of a reflective material.

The cavity 100a may be formed in a cup shape, a concave shape, or the like, with the upper surface of the body 100 being opened. In this case, the upper shape of the cavity 100a is circular. The light emitting device 140 may be disposed on the bottom surface of the body 100 exposed by the cavity 100a.

Since the shape of the light emitting element 140 and the shape of the upper surface of the cavity 100a differ from each other in general, the distance between the light emitting element 140 and the inner surface of the body 100 is partially different, Do. The light emitted from the light emitting device 140 is reflected by the inner side of the body 100 and then emitted again to the light emitting element 140. [ The light may be absorbed by the device 140 and the light efficiency may be lowered.

In order to prevent the above problem, the embodiment of the present invention has a hexagonal shape in which the upper surface of the light emitting device 140 is surrounded by six line segments when the upper surface of the cavity 100a is circular. That is, the shape of the cavity 100a and the shape of the light emitting device 140 may be similar to each other, thereby improving the uniformity of the gap between the light emitting device 140 and the inner surface of the body 100. [

FIG. 3 is a plan view of a light emitting device package including a light emitting device having a quadrangular top surface, and Tables 1 and 2 show the light emitting device package of FIGS. 1A and 3, .

A general light emitting device package having a quadrangular shape of the light emitting device 140 is formed between the side surface of the light emitting device 140 and the side surface in the body 100 The largest gap d1 between the narrowest interval d2 and the widest gap d2 is large. On the other hand, when the light emitting device 140 is hexagonal as in the present invention, the difference between the narrowest distance d1 and the widest distance d2 among the gaps between the side surface of the light emitting device 140 and the inner side surface of the body 100 .

Type of light emitting device Circular Cavity Radius (㎛) Spacing (탆) d1: d2
The narrowest interval (d1) The widest spacing (d2) Typical light emitting device package Square 975 339 525 1: 1.55 The light emitting device package hexagon 975 417 491 1: 1.17

When the radius of the circular cavity 100a is increased to 1200 占 퐉 as shown in Table 2 below, the distance d1 between the side of the light emitting device 140 of the present invention and the inner side surface of the body 100, The deviation of the wide interval d2 is further reduced.

Type of light emitting device Circular Cavity Radius (㎛) Spacing (탆) d1: d2
The narrowest interval (d1) The widest spacing (d2) Typical light emitting device package Square 1200 564 750 1: 1.33 The light emitting device package hexagon 1200 642 716 1: 1.11

That is, according to the present invention, when the upper surface of the cavity 100a is circular, the upper surface of the light emitting device 140 is formed in a hexagonal shape so that the narrowest distance d1 between the light emitting device 140 and the inner surface of the body 100, And the widest gap d2 can be reduced. Accordingly, the uniformity of the distance between the side surface of the light emitting device 140 and the inner side surface of the body 100 is improved, and the uniformity of the light emitted from the light emitting device package is improved, thereby reducing the color deviation according to the directional angle.

Particularly, when the distance between the side surface of the light emitting device 140 and the side surface of the body 100 is too narrow, the light emitted from the light emitting device 140 is totally reflected on the inner side surface of the body 100, And the light efficiency may be lowered. Therefore, it is preferable that the narrowest distance d1 between the side surface of the light emitting element 140 and the inner side surface of the body 100 is wider than 150 m.

In addition, when the distance between the side surface of the light emitting device 140 and the inner side surface of the body 100 is too wide, it is difficult to miniaturize the light emitting device package and the manufacturing cost increases. Therefore, it is preferable that the widest distance d2 between the side surface of the light emitting device 140 and the inner side surface of the body 100 is narrower than 2000 占 퐉.

In this case, it is preferable that the ratio of the narrowest distance d1 to the widest distance d2 is 1: 1.2 or less in order to reduce the color deviation of each directional angle. It is preferable that the narrowest distance d1 between the side surface of the light emitting device 140 and the inner side surface of the body 100 is between 150 mu m and 700 mu m and between the side surface of the light emitting device 140 and the inside surface of the body 100 It is preferable that the widest distance d2 of the protrusions is 150 mu m to 840 mu m.

Referring again to FIG. 2, the light emitting device 140 disposed in the cavity 100a includes the light emitting structure 142 disposed on the substrate 141, and may include only the light emitting structure 142. Referring to FIG. The light emitting structure 142 includes a first semiconductor layer 142a, a second semiconductor layer 142b, an active layer 142c, a first electrode 142d, and a second electrode 142e.

The first semiconductor layer 142a may be formed of a compound semiconductor such as a group III-V element, a group II-VI element, or the like, and may be doped with a first conductivity type dopant. For example, the first semiconductor layer 142a may be a semiconductor having a composition formula of InxAlyGa1-x-yN (0? X? 1, 0? Y? 1, 0? X + y? , Sn, and the like may be doped.

The active layer 142b can generate light by energy generated in the recombination process of electrons and holes provided from the first semiconductor layer 142a and the second semiconductor layer 142c . The active layer 142b may be a compound semiconductor of a semiconductor compound, for example, a Group 3-V-5 or a Group 2-VI-6 compound semiconductor, and may be a single well structure, a multi-well structure, a quantum- (Quantum Dot) structure or the like. In the case where the active layer 142b is a quantum well structure, a well layer having a composition formula of InxAlyGa1-x-yN (0? X? 1, 0? Y? 1, 0? X + y? 1, 0? A? 1, 0? B? 1, 0? A + b? 1). The well layer may be a material having a band gap lower than the energy band gap of the barrier layer.

The second semiconductor layer 142c may be formed of a compound semiconductor such as a group III-V, a group II-VI, or the like, and the second conductive dopant may be doped. For example, the second semiconductor layer 142c may be a semiconductor having a composition formula of InxAlyGa1-x-yN (0? X? 1, 0? Y? 1, 0? X + y? , A p-type dopant such as Ca, Sr, Ba, or the like can be doped.

Although a single light emitting device 140 is shown in the drawing, when the light emitting device package includes two or more light emitting devices 140, the body 100 includes two separated cavities 100a, (140) may be respectively disposed in the cavity (100a). The light emitting device 140 may emit at least one light selected from ultraviolet light, red light, green light, blue light, and white light.

The first semiconductor layer 142a and the first electrode 142d are electrically connected to each other and the second semiconductor layer 142c and the second electrode 142e are electrically connected to each other so that the first and second electrodes 142d And 142e can be connected to the electrode member through the wire. In this case, the first and second electrodes 142d and 142e may be formed of a transparent conductive oxide (TCO) or an opaque metal.

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 opaque metal may be selected from Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au and Hf. The first and second electrodes 142d and 142e may be formed of one or a plurality of layers of a mixture of a transparent conductive oxide film and an opaque metal. However, the present invention is not limited thereto.

The shape of the light emitting device 140 may be easily changed, and the electrical connection between the light emitting device 140 and the electrode member 120 may be performed by various methods.

The molding member 110 may be formed on the light emitting device 140 and the molding member 110 may be filled in the cavity 100a to cover the light emitting device 140. [ The molding member 110 may include a light-transmitting resin such as epoxy or silicon. Further, although not shown, the molding member 110 may be selectively doped with a fluorescent material or a diffusing agent, but the present invention is not limited thereto. The phosphor may include a YAG-based, a silicate-based, or a TAG-based fluorescent material.

Further, although not shown, an optical lens may be further formed on the molding member 110 so as to cover the molding member 110. The optical lens may have a concave lens shape, a convex lens shape, a convex lens shape, , But is not limited thereto.

Although the upper surface of the light emitting device 140 is shown as a hexagonal shape in the drawing, the upper surface of the light emitting device 140 may be a polygonal shape surrounded by seven or more line segments so as to have a circular shape.

4A and 4B are plan views of a light emitting device package according to another embodiment of the present invention.

As shown in FIG. 4A, when the upper surface of the cavity 100a is circular, the upper surface of the light emitting device 140 may be octagonal, or the light emitting device 140 may be a twin triangle as shown in FIG. 4B. In this case, the deviation (d1, d2) between the side surface of the light emitting element 140 and the inside surface of the body 100 can be further reduced.

5A to 5D are plan views of a light emitting device package according to another embodiment of the present invention.

In the light emitting device package according to another embodiment of the present invention, the upper surface of the light emitting device 140 and the upper surface of the cavity 100a are the same.

Specifically, the upper surface of the cavity 100a and the upper surface of the light emitting device 140 are polygons formed by the same number of line segments. Particularly, as the angle of the corner of the cavity 100a becomes narrower, the light emitted from the light emitting device 140 may not be emitted to the outside, and a phenomenon may occur in the corner. Therefore, it is preferable that the corner of the cavity 100a is a certain angle or more. To this end, the cavity 100a and the upper surface of the light emitting device 140 are preferably hexagonal having an angle of at least 120 degrees.

That is, as shown in FIG. 5A, the upper surface of the light emitting device 140 and the cavity 100a may be formed in a hexagonal shape. In this case, there are six virtual connection lines connecting the vertexes of the selected one of the six vertexes of the upper surface of the light emitting device 140 and the vertexes closest to the six vertexes of the upper surface of the cavity 100a, The connection line of the device meets at one point.

As shown in FIG. 5B, the upper surface of the light emitting device 140 and the cavity 100a may be octagonal, or the upper surface of the cavity 100a may be formed to have a diagonal shape, as shown in FIG. 5C.

As described above, the ratio of the narrowest distance d1 to the widest distance d2 approaches 1: 1 as the number of line segments forming the upper surface of the light emitting device 140 increases.

5D, when the light emitting device 140 and the upper surface of the cavity 100a are both circular, the distance d between the side surface of the light emitting device 140 and the inside surface of the body 100a is all the same Do. Therefore, the ratio of the narrowest distance d1 to the widest distance d2 is 1: 1. At this time, the distance d between the side surface of the light emitting element 140 and the inside surface of the body 100a is 150 mu m to 2000 mu m.

In this case, the uniformity of light emission is improved and the color deviation according to the directivity angle can be effectively reduced. Although not shown, both the light emitting device 140 and the upper surface of the cavity 100a may be formed in an elliptical shape.

As described above, in the light emitting device package of the embodiment of the present invention, when the upper surface of the cavity 100a is circular, the light emitting device 140 disposed in the cavity 100a has a polygonal structure in which the upper surface is surrounded by six or more line segments So that the uniformity of the gap between the side surface of the light emitting device 140 and the side surface of the body 100 can be improved. The light emitting device 140 and the cavity 100a are formed in the same shape so that the uniformity of the gap between the light emitting device 140 and the inner side surface of the body 100 can be improved.

Meanwhile, the light emitting device package may further include an optical member such as a light guide plate, a prism sheet, and a diffusion sheet, and may function as a backlight unit. Further, the light emitting element of the embodiment can be further applied to a display device, a lighting device, and a pointing device.

At this time, the display device may include a bottom cover, a reflector, a light emitting module, a light guide plate, an optical sheet, a display panel, an image signal output circuit, and a color filter. The bottom cover, the reflector, the light emitting module, the light guide plate, and the optical sheet may form a backlight unit.

The reflector is disposed on the bottom cover, and the light emitting module emits light. The light guide plate is disposed in front of the reflection plate to guide light emitted from the light emitting module forward, and the optical sheet includes a prism sheet or the like and is disposed in front of the light guide plate. The display panel is disposed in front of the optical sheet, and the image signal output circuit supplies an image signal to the display panel, and the color filter is disposed in front of the display panel.

The lighting device may include a light source module including a substrate and a light emitting device package of the embodiment, a heat dissipation unit for dissipating heat of the light source module, and a power supply unit for processing or converting an electrical signal provided from the outside, have. Further, the lighting device may include a lamp, a head lamp, or a street lamp or the like.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. It will be clear to those who have knowledge.

100: Body 100a: Cavity
110: molding member 120: electrode member
140: light emitting element 141: substrate
142: light emitting structure 142a: first semiconductor layer
142b: active layer 142c: second semiconductor layer
142d: first electrode 142e: second electrode

Claims (11)

A body including a cavity whose top surface is circular; And
And a polygonal light emitting element disposed in the cavity and having an upper surface surrounded by at least six line segments. The method according to claim 1,
Wherein a distance between the light emitting device side and the inner side surface of the body is 150 mu m to 700 mu m. The method according to claim 1,
Wherein a widest interval between the light emitting device side and the inner side surface of the body is 150 占 퐉 to 840 占 퐉. The method according to claim 1,
Wherein the narrowest interval and the widest spacing ratio of the distance between the side surface of the light emitting element and the inner side surface of the body are more than 1: 1 and not more than 1: 1.2. A body including a cavity whose top surface is circular; And
A light emitting element disposed in the cavity and having a top surface in a circular shape,
Wherein a gap between the side surface of the light emitting device and the inside surface of the body is the same. 6. The method of claim 5,
Wherein the interval is 150 占 퐉 to 2000 占 퐉. A body including a cavity whose top surface is a polygon surrounded by at least six line segments; And
And a light emitting element which is disposed in the cavity and whose upper surface is the same polygon as the cavity. 8. The method of claim 7,
When the cavity and the light emitting element are hexagons surrounded by n (n is a natural number of 6 or more) line segments on the upper surface,
Wherein the light emitting device package meets at a point of imaginary n connecting lines connecting vertexes of a selected one of n vertexes of the upper surface of the light emitting device and vertexes of the n vertices of the upper surface of the cavity. 8. The method of claim 7,
Wherein a distance between the light emitting device side and the inner side surface of the body is 150 mu m to 700 mu m. 8. The method of claim 7,
Wherein a widest interval between the light emitting device side and the inner side surface of the body is 150 占 퐉 to 840 占 퐉. 8. The method of claim 7,
Wherein the narrowest interval and the widest spacing ratio of the distance between the side surface of the light emitting element and the inner side surface of the body are more than 1: 1 and not more than 1: 1.2.

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