KR100887072B1 - Semiconductor light emitting device and semiconductor light emitting device package using the same - Google Patents

Abstract

A semiconductor light emitting device and a semiconductor light emitting device package using the same are provided to maximize luminous efficiency by securing a maximum light emitting area and by minimizing reflection or absorption of an emitted light. A semiconductor light emitting device(100) comprises a first conductive semiconductor layer(110), an active layer(120), a second conductive semiconductor layer(130), a second electrode layer(140), an electrode insulation part(150), a first electrode layer(160), and a conductive substrate. The conductive substrate includes a first conductive substrate(171), a second conductive substrate(172), and a substrate insulation part(180). The first conductive substrate is contacted with the first electrode layer. The second conductive substrate is contacted with the second electrode layer. The substrate insulation part electrically separates the first and the second conductive substrates. The first electrode layer is contacted with the first conductive semiconductor layer, and is isolated with the second conductive substrate. The second electrode layer is contacted with the second conductive substrate, and is isolated with the first electrode layer.

Description

Semiconductor light emitting device, and semiconductor light emitting device package using the same {Semiconductor light emitting device and semiconductor light emitting device package using the same}

The present invention relates to a semiconductor light emitting device and a semiconductor light emitting device package using the same, and more particularly, to minimize the reflection or absorption of the emitted light, to secure the maximum light emitting area to maximize the luminous efficiency and at the same time small electrode The present invention relates to a high quality semiconductor light emitting device capable of uniform current distribution, high reliability and low mass production, and a semiconductor light emitting device package using the same.

A light emitting device is a device in which a material included in the device emits light. For example, a light emitting diode (LED) is used to bond energy of electron / hole recombination in the form of a semiconductor bonded using a diode. There is an element that converts and emits light. Such light emitting devices are widely used as lighting, display devices, and light sources, and their development is being accelerated.

In particular, the development of general lighting using light emitting diodes has recently been fueled by the commercialization of mobile phone keypads, side viewers, camera flashes, etc. using gallium nitride (GaN) based light emitting diodes, which have been actively developed and used. Its applications such as backlight units of large TVs, automotive headlamps, and general lighting have moved from small portable products to large size, high output, high efficiency, and reliable products, requiring light sources that exhibit the characteristics required for such products.

The semiconductor junction light emitting device structure is usually a junction structure of a p-type semiconductor and an n-type semiconductor. In the semiconductor junction structure, there may be light emission due to electron / hole recombination in the junction region of both semiconductors, but an active layer for activating the light emission may be provided. The semiconductor junction light emitting device has a horizontal structure and a vertical structure according to the position of the electrode for the semiconductor layer, and there are growth-type (epi-up) and flip-chip (flip-chip) in the horizontal structure. In view of the characteristics of the product used as described above, the structural characteristics of each of the light emitting elements required are considered.

The growth type light emitting device has a problem in that the light emitting area for forming the electrode is reduced, and the flip chip type light emitting device has to be bonded by bonding the n-type electrode and the p-type electrode together on the same plane in spite of the advantages of excellent light emission efficiency. As the separation between the electrode contact portion and the electrode after bonding is frequently required, expensive and precise process equipment is required, resulting in high manufacturing cost, low productivity, low yield, and product reliability.

In addition, in the case of manufacturing a large area light emitting device for high output, the vertical semiconductor light emitting device is required to have a high area ratio with respect to the substrate of the electrode for current dispersion. Accordingly, light loss and luminous efficiency due to the limitation of light extraction and light absorption are reduced, and there is a problem that the reliability of the product is lowered.

The present invention is to solve the above problems, an object of the present invention is to minimize the reflection or absorption of the emitted light, to maximize the luminous efficiency by ensuring the maximum light emitting area and at the same time uniform current distribution to a small area of the electrode It is to provide a high quality semiconductor light emitting device and a semiconductor light emitting device package using the same which have high reliability and low cost.

In accordance with an aspect of the present invention, a semiconductor light emitting device includes a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, a second electrode layer, an electrode insulating portion, a first electrode layer, and a conductive substrate. A semiconductor light emitting device sequentially stacked includes a first conductive substrate in contact with a first electrode layer, a second conductive substrate in contact with a second electrode layer through a second conductive substrate connection portion, and first and second conductive substrates. A first insulating layer, wherein the first insulating layer is electrically connected to the first conductive semiconductor layer and electrically insulated from the second conductive semiconductor layer and the active layer. One or more contact holes extending to at least a portion of the semiconductor layer, the second electrode layer being electrically insulated from the second conductive substrate, the second electrode layer being electrically connected to the conductive substrate, One or more second conductive substrate connections formed through the first electrode layer to be electrically insulated from the first electrode layer.

The length of the first and second conductive substrates is 80 μm, and the thickness of the substrate insulating portion between both substrates may be 50 μm to 100 μm.

The first and second conductive substrates may be metallic substrates including any one of Au, Ni, Cu, and W metals.

The second electrode layer preferably reflects light generated from the active layer, and may include, for example, a metal of any one of Ag, Al, and Pt.

According to another aspect of the invention, the light emitting device package main body formed with a groove on the upper surface; A first lead frame and a second lead frame mounted on the package body and exposed to the bottom of the groove and spaced apart from each other by a predetermined distance; And a semiconductor light emitting device mounted on the first lead frame and the second lead frame, wherein the semiconductor light emitting device includes a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, a second electrode layer, an electrode insulating portion, The first electrode layer and the conductive substrate are sequentially stacked, and the conductive substrate is a first conductive substrate in contact with the first electrode layer, a second conductive substrate in contact with the second electrode layer through the second conductive substrate connection portion, and first and second conductive layers. And a substrate insulating portion for electrically separating the substrate, wherein the first electrode layer is electrically connected to the first conductive semiconductor layer and electrically insulated from the second conductive semiconductor layer and the active layer from one surface of the first electrode layer. One or more contact holes extending to at least a portion of the conductive semiconductor layer, wherein the second electrode layer is electrically connected to the conductive substrate and electrically insulated from the first electrode layer. The semiconductor light emitting device characterized in that a formed through the first electrode layer or the second conductive substrate comprises a further connection is provided.

The thickness of the substrate insulator is preferably equal to or larger than the distance between the first lead frame and the second lead frame. For example, the thickness of the substrate insulator may be 50 μm to 100 μm.

As described above, the semiconductor light emitting device according to the present invention does not form all the electrode portions of the semiconductor layer located in the light emitting direction on the light emitting surface, except that a portion thereof is formed under the active layer, so that the emitted light is formed by the electrode portion. The phenomenon of being reflected or absorbed can be prevented, and the light emitting area can also be secured to the maximum, thereby maximizing light emission.

In addition, the electrode unit is provided with one or more and contact holes so as to facilitate current distribution, and thus, it is possible to uniformly distribute current to electrodes having a small area.

In addition, since the conductive substrate is in contact with each electrode and can be easily die-bonded and packaged, there is an effect of showing excellent mass productivity at low cost.

Therefore, according to the present invention, it is possible to implement a high quality semiconductor light emitting device and a semiconductor light emitting device package with high reliability and low cost.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art.

1 is a perspective view of a semiconductor light emitting device according to an embodiment of the present invention.

The semiconductor light emitting device 100 according to the exemplary embodiment of the present invention may include a first conductive semiconductor layer 110, an active layer 120, a second conductive semiconductor layer 130, a second electrode layer 140, and an electrode insulating portion. The 150, the first electrode layer 160, and the conductive substrates 171, 172, and 180 are sequentially stacked. The conductive substrates 171, 172, and 180 may contact the second electrode layer 140 through the first conductive substrate 171 and the second conductive substrate connecting portion 141 to contact the first electrode layer 160. The substrate 172 may include an electrode insulating unit 150 that electrically separates the first and second conductive substrates 171 and 172. The first electrode layer 160 is electrically connected to the first conductive semiconductor layer 110, and the second conductive semiconductor layer 130 and the active layer 120 are electrically insulated from one surface of the first electrode layer 160. One or more contact holes 161 extending from the first conductive semiconductor layer 110 to at least a portion of the first conductive semiconductor layer 110. One or more second conductive substrate connection portions formed through the first electrode layer 160 to be electrically connected to the second conductive substrate 172 and electrically insulated from the first electrode layer 160. 141.

Light emission of the semiconductor light emitting device 100 is performed in the first conductive semiconductor layer 110, the active layer 120, and the second conductive semiconductor layer 130. That is, the semiconductor light emitting device 100 may include the first electrode layer 160 and the second conductive semiconductor layer electrically connected to the first conductive semiconductor layer 110 together with the semiconductor layers 110 and 130 and the active layer. And a second electrode layer 140 electrically connected to the 130, and an electrode insulator 150 for electrically insulating the electrode layers 140 and 160.

Each of the semiconductor layers 110 and 130 may be formed of, for example, an inorganic semiconductor such as a GaN based semiconductor, a ZnO based semiconductor, a GaAs based semiconductor, a GaP based semiconductor, or a GaAsP based semiconductor. The formation of the semiconductor layer may be performed using, for example, a molecular beam epitaxy (MBE) method. In addition, the semiconductor layers may be appropriately selected from the group consisting of a group III-V semiconductor, a group II-VI semiconductor, and Si. The semiconductor layers 110 and 130 are doped with an appropriate impurity in consideration of the respective conductivity type to the semiconductor described above.

The active layer 120 is a layer that activates light emission and is formed using a material having an energy band gap less than that of the first conductive semiconductor layer 110 and the second conductive semiconductor layer 130. For example, when the first conductive semiconductor layer 110 and the second conductive semiconductor layer 130 are GaN-based compound semiconductors, the active layer is formed using an InAlGaN-based compound semiconductor having an energy band gap smaller than that of GaN. 120 may be formed. That is, the active layer 120 may be In _x Al _y Ga _(1-xy) N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1).

At this time, it is preferable that the impurities are not doped due to the characteristics of the active layer 120, and the wavelength of light emitted by controlling the molar ratio of the constituent material may be adjusted. Therefore, the semiconductor light emitting device 100 may emit light of any one of infrared rays, visible rays, and ultraviolet rays according to the characteristics of the active layer 120.

Since the electrode layers 140 and 160 are layers for applying a voltage to the same conductive semiconductor layer, the electrode layers 140 and 160 may include a metal in consideration of electrical conductivity. That is, the electrode layers 140 and 160 are electrodes that electrically connect the semiconductor layers 110 and 130 to an external power source (not shown). The electrode layers 140 and 160 may include, for example, Ti as an n-type electrode and Pd or Au as a p-type electrode.

Since the first electrode layer 160 is connected to the first conductive semiconductor layer 110 and the second electrode layer 140 is connected to the second conductive semiconductor layer 130, the electrode insulating part is connected to different conductive types. Electrically separated from each other through 150. Since the electrode insulating part 150 is preferably made of a material having low electrical conductivity, for example, the electrode insulating part 150 may include an oxide such as SiO ₂ .

The first electrode layer 160 is electrically connected to the first conductive semiconductor layer 110, and the second conductive semiconductor layer 130 and the active layer 120 are electrically insulated from one surface of the first electrode layer 160. One or more contact holes 161 extend to at least a portion of the first conductive semiconductor layer 110.

One or more second conductive substrate connection portions formed through the first electrode layer 160 to be electrically connected to the second conductive substrate 172 and electrically insulated from the first electrode layer 160. 141. The contact hole 161 and the second conductive substrate connecting portion 141 will be further described below with reference to FIG. 3.

The second electrode layer 140 preferably reflects light generated from the active layer 120. Since the second electrode layer 140 is positioned below the active layer 120, the second electrode layer 140 is positioned on a surface opposite to the light emitting direction of the semiconductor light emitting device 100 based on the active layer 120. The light emitting efficiency of the semiconductor light emitting device 100 traveling from the active layer 120 to the second electrode layer 140 is opposite to that of the semiconductor light emitting device 100 and the light traveling toward the second electrode layer 140 is reflected. Therefore, when the second electrode layer 140 exhibits light reflectivity, the reflected light is directed toward the light emitting surface, and the light emitting efficiency of the semiconductor light emitting device 100 is increased.

In order to reflect the light generated from the active layer 120, the second electrode layer 140 is preferably a white-based metal in the visible light region. For example, the second electrode layer 140 may be any one of Ag, Al, and Pt.

The conductive substrates 171, 172, and 180 may contact the second electrode layer 140 through the first conductive substrate 171 and the second conductive substrate connecting portion 141 to contact the first electrode layer 160. The substrate 172 may include an electrode insulating unit 150 that electrically separates the first and second conductive substrates 171 and 172.

The first conductive substrate 171 and the second conductive substrate 172 may be metallic substrates or conductive semiconductor substrates. When the first and second conductive substrates 171 and 172 are metals, the first and second conductive substrates 171 and 172 may be made of any one metal of Au, Ni, Cu, and W. In addition, when the first and second conductive substrates 171 and 172 are semiconductor substrates, the semiconductor substrate may be any one of Si, Ge, and GaAs. After using a non-conductive substrate such as a sapphire substrate having a relatively low lattice mismatch as a growth substrate, the non-conductive substrate is removed and formed.

The substrate insulating unit 180 electrically separates the first and second conductive substrates 171 and 172 having different conductivity types. Therefore, it is desirable to be composed of a material having low electrical conductivity. For example, the substrate insulation unit 180 may include an oxide such as SiO ₂ .

The conductive substrates 171, 172, 180 may be formed using a known method such as a plating method or a substrate bonding method. In detail, the plating method forms a seed layer to form a substrate, or separately prepares the conductive substrates 171, 172, and 180 to form the first electrode layer 160 using a conductive adhesive such as Au, Au-Sn, or Pb-Sr. A substrate bonding method for bonding to () may be used. However, since the conductive substrates 171, 172, and 180 are for electrically connecting the electrode layers 140 and 160 to an external power source (not shown), it is preferable to use the plating method in consideration of the fact that the conductive substrates 171, 172, and 180 are formed to have a predetermined length.

FIG. 2A is a plan view of the semiconductor light emitting device of FIG. 1, FIG. 2B is a bottom view of the semiconductor light emitting device of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line A-A 'of the top surface of the semiconductor light emitting device shown in FIG. to be.

Referring to FIG. 2A, the contact hole 161 is illustrated by a dotted line to indicate the position of the contact hole 161 although it does not appear on the upper surface of the semiconductor light emitting device 100. In addition, the region 130 of the substrate insulation portion 180, the region 110 of the first conductive substrate 171, and the second conductive portion are formed by using lines B and B ′ to indicate the position of the substrate insulation portion 180. The region 130 of the substrate 172 is shown (see FIG. 2B).

In FIG. 2A, six contact holes 161 are shown, three of which are positioned on the first conductive substrate region and three of which are on the second conductive substrate region 120. Therefore, the contact hole 161 located on the second conductive substrate region 120 may be electrically connected to the contact hole 161 on the first conductive substrate using the predetermined wiring unit 162.

Referring to FIG. 3, a contact hole 161 formed on the first electrode layer 160 is illustrated. The contact hole 161 may be electrically connected to the first conductive semiconductor layer 110, and the first conductive semiconductor layer 130 and the active layer 120 may be electrically insulated from one surface of the first electrode layer 160. It extends to at least a partial region of the conductive semiconductor layer 110.

The contact hole 161 extends from the interface of the first electrode layer 160 and the second electrode layer 140 to the inside of the first conductive semiconductor layer 110. The contact hole 161 extends through the second conductive semiconductor layer 130 and the active layer 120 to the first conductive semiconductor layer 110, and at least the active layer 120 and the first conductive semiconductor layer 110. ) Extends to the interface. Preferably, it extends to a part of the first conductive semiconductor layer 110. However, since the contact hole 161 is for electrical connection and current distribution, the contact hole 161 does not need to extend to the outer surface of the first conductive semiconductor layer 110 because the contact hole 161 serves the purpose. .

Since the contact hole 161 is to disperse current in the first conductive semiconductor layer 110, the contact hole 161 should have a predetermined area. The number of contact holes 161 is preferably formed on the first conductive semiconductor layer 110 in a predetermined number as small as possible to distribute the current evenly. If the contact holes 161 are formed in too small a number, current dispersion becomes difficult, and thus the electrical characteristics may be deteriorated. If the contact holes 161 are formed in a too small number, the light emitting area may be reduced due to difficulty in forming and reduction of the active layer. In consideration of these conditions, the number may be appropriately selected. Therefore, the contact hole 161 is implemented in a shape in which current distribution is effective while occupying as little area as possible.

The contact hole 161 is formed from the second electrode layer 120 to the inside of the first conductive semiconductor layer 110. Since the contact hole 161 is for dispersing current of the first conductive semiconductor layer, the second conductive semiconductor layer 130 and the active layer are formed. It is necessary to be electrically separated from the 120. Therefore, the second electrode layer 120, the second conductive semiconductor layer 130, and the active layer 120 may be electrically separated from each other. Therefore, the electrode insulating part 150 may extend while surrounding the circumference of the contact hole 161. In addition, when the contact hole 161 is present above the second conductive substrate 172, the first electrode layer 160 may be electrically separated from the second conductive substrate 172.

One or more second conductive substrate connection portions formed through the first electrode layer 160 to be electrically connected to the second conductive substrate 172 and electrically insulated from the first electrode layer 160. 141. In FIG. 3, the second conductive substrate connection part 141 is shown to be separated from the second electrode layer 140 by a dotted line, which is formed by extending the second electrode layer 140. It can mean, or can be formed using another electrode material separately.

The second electrode layer 140 is electrically connected to the second conductive substrate 172 through the second conductive substrate connecting portion 141. Accordingly, the semiconductor light emitting device 100 is disposed in the light emitting direction of the light generated from the active layer 120. It is not necessary to provide a separate bonding pad can obtain a higher light extraction efficiency.

The length l of the first and second conductive substrates 171 and 172 is preferably 80 μm or more. When the lengths of the first and second conductive substrates 171 and 172 are longer than or equal to a predetermined length, they are without a separate electrode pad. It can be mounted in a package, which is highly efficient in terms of process. In addition, in consideration of the distance between the lead frames of the semiconductor light emitting device package, the thickness d1 of the substrate insulation unit 180 between the substrates 171 and 172 may be 50 μm to 100 μm. However, the thickness of the substrate insulation 180 may be adjusted according to the package to be applied.

4 is a cross-sectional view of a semiconductor light emitting device package according to an embodiment of the present invention. According to another aspect of the present invention, a semiconductor light emitting device package 200 is provided. The semiconductor light emitting device package 200 may include a light emitting device package body 241a, 241b, and 242 having grooves formed on an upper surface thereof; A first lead frame 251a and a second lead frame 251b mounted on the package bodies 241a, 241b, and 242 and exposed to the bottom of the groove and spaced apart from each other by a predetermined distance; And light emitting devices 210, 221, 222, and 230 mounted on the first lead frame 251a and the second lead frame 251b. The semiconductor light emitting device is a semiconductor light emitting device according to an embodiment of the present invention described with reference to FIG. 1. Hereinafter, the description of the same components described above will be omitted.

The semiconductor light emitting devices 210, 221, 222, and 230 may include a light emitting part 210 including first and second semiconductor layers, an active layer, and an electrode layer, and a conductive substrate 221, 222, 230. In the conductive substrates 221, 222, and 230, the first conductive substrate 211 is electrically connected to the first lead frame 251a, and the second conductive substrate 172 is in contact with the second lead frame 252a. Located.

The semiconductor light emitting devices 210, 221, 222, and 230 electrically separate the conductive substrate using the substrate insulating unit 230, and have the first conductive substrate 221 and the second conductive substrate 222 having conductivity. By connecting to the leadframe, it can be mounted in a simple process. The semiconductor light emitting device according to the present invention can be mounted on the package in a relatively simple die bonding type while having a vertical structure while ensuring the luminous efficiency as much as possible. Therefore, the process can be performed at a relatively low cost.

For this purpose, the thickness of the substrate insulating portion is preferably equal to or greater than the distance between the first lead frame and the second lead frame. For example, the thickness of the substrate insulating portion may be 50 μm to 100 μm. In addition, in consideration of ease of mounting, the thickness of the conductive substrates 221, 222, 230 is preferably 80 μm or more.

The invention is not to be limited by the foregoing embodiments and the accompanying drawings, but should be construed by the appended claims. In addition, it will be apparent to those skilled in the art that various forms of substitution, modification, and alteration are possible within the scope of the present invention without departing from the technical spirit of the present invention.

1 is a perspective view of a semiconductor light emitting device according to an embodiment of the present invention.

2A is a plan view of the semiconductor light emitting device of FIG. 1, and FIG. 2B is a bottom view of the semiconductor light emitting device of FIG.

FIG. 3 is a cross-sectional view taken along line AA ′ of the top surface of the semiconductor light emitting device shown in FIG. 2A.

4 is a cross-sectional view of a semiconductor light emitting device package according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100 Semiconductor Light Emitting Device 110 First Conductive Semiconductor Layer

120 Active layer 130 Second conductive semiconductor layer

140 Second electrode layer 150 Electrode insulation

160 First electrode layer 171 First conductive substrate

172 Second conductive substrate 173 Substrate insulation

Claims (9)

A semiconductor light emitting device in which a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, a second electrode layer, an electrode insulating portion, a first electrode layer, and a conductive substrate are sequentially stacked, The conductive substrate includes a first conductive substrate in contact with the first electrode layer, a second conductive substrate in contact with the second electrode layer, and a substrate insulating portion electrically separating the first and second conductive substrates, The first electrode layer is at least a portion of the first conductive semiconductor layer from one surface of the first electrode layer to be electrically connected to the first conductive semiconductor layer and electrically insulated from the second conductive semiconductor layer and the active layer. One or more contact holes extending to an area and electrically insulated from the second conductive substrate, The second electrode layer includes one or more second conductive substrate connection parts formed through the first electrode layer to be electrically connected to the second conductive substrate and electrically insulated from the first electrode layer. Semiconductor light emitting device. The method of claim 1, The semiconductor light emitting device of claim 1, wherein the first and second conductive substrates have a length of 80 μm. The method of claim 1, The thickness of the substrate insulating portion is a semiconductor light emitting device, characterized in that 50 ㎛ to 100 ㎛. The method of claim 1, The first and the second conductive substrate is a semiconductor light emitting device, characterized in that the metallic substrate containing any one of Au, Ni, Cu, and W metal. The method of claim 1, And the second electrode layer reflects light generated from the active layer. The method of claim 5, The second electrode layer includes any one of Ag, Al, and Pt. A light emitting device package body having a groove formed on an upper surface thereof; A first lead frame and a second lead frame mounted on the package body and exposed to a bottom surface of the groove and spaced apart from each other by a predetermined distance; And And a semiconductor light emitting device mounted on the first lead frame and the second lead frame. The semiconductor light emitting device is a semiconductor light emitting device in which a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, a second electrode layer, an electrode insulating portion, a first electrode layer, and a conductive substrate are sequentially stacked. The conductive substrate includes a first conductive substrate in contact with the first electrode layer, a second conductive substrate in contact with the second electrode layer, and a substrate insulating portion electrically separating the first and second conductive substrates, The first electrode layer is at least a portion of the first conductive semiconductor layer from one surface of the first electrode layer to be electrically connected to the first conductive semiconductor layer and electrically insulated from the second conductive semiconductor layer and the active layer. One or more contact holes extending to an area and electrically insulated from the second conductive substrate, The second electrode layer includes one or more second conductive substrate connection parts formed through the first electrode layer to be electrically connected to the second conductive substrate and electrically insulated from the first electrode layer. Semiconductor light emitting device package. The method of claim 7, wherein The thickness of the substrate insulating portion is a semiconductor light emitting device package, characterized in that equal to or greater than the distance between the first lead frame and the second lead frame. The method of claim 7, wherein The thickness of the substrate insulating portion is a semiconductor light emitting device package, characterized in that 50 ㎛ to 100 ㎛.

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