KR20150141198A - Semiconductor light emitting device - Google Patents

Abstract

The present disclosure relates to a semiconductor light emitting device comprising: multiple semiconductor layers which include a first semiconductor layer having first conductivity, a second semiconductor layer having second conductivity different from the first conductivity, and an active layer interposed between the first semiconductor layer and the second semiconductor layer and generating light through recombination of electrons and holes; a first electrode unit which is electrically connected to the first semiconductor layer and supplies one of electrons and holes; a second electrode unit which is electrically connected to the second semiconductor layer and supplies the other of electrons and holes; a non-conductive reflective film which is formed on the semiconductor layers to reflect the light generated in the active layer to the first semiconductor layer, and has an opening formed; and an additional reflective film which is formed on the non-conductive reflective film to reflect the light passing through the non-conductive reflective film, to the first semiconductor layer, wherein at least one of the first electrode unit and the second electrode unit includes a lower electrode, at least a part of which is exposed through the opening, and which is electrically connected to the semiconductor layers, and a connection electrode which is formed between the non-conductive reflective film and the additional reflective film and is electrically connected to the lower electrode through the opening.

Description

Technical Field [0001] The present invention relates to a semiconductor light emitting device,

The present disclosure relates generally to a semiconductor light emitting device, and more particularly to a semiconductor light emitting device in which luminance is improved by reducing light loss.

Here, the semiconductor light emitting element means a semiconductor light emitting element that generates light through recombination of electrons and holes, for example, a group III nitride semiconductor light emitting element. The Group III nitride semiconductor is made of a compound of Al (x) Ga (y) In (1-x-y) N (0? X? 1, 0? Y? 1, 0? X + y? A GaAs-based semiconductor light-emitting element used for red light emission, and the like.

Herein, the background art relating to the present disclosure is provided, and these are not necessarily meant to be known arts.

1 is a view showing an example of a semiconductor light emitting device disclosed in U.S. Patent No. 7,262,436.

The semiconductor light emitting device includes a substrate 100, an n-type semiconductor layer 300 grown on the substrate 100, an active layer 400 grown on the n-type semiconductor layer 300, p An n-side bonding pad 800 formed on the n-type semiconductor layer 300 exposed by etching, electrodes 901, 902, and 903 functioning as a reflective film formed on the n-type semiconductor layer 500, the p-type semiconductor layer 500, .

A chip having such a structure, that is, a chip in which both the electrodes 901, 902, 903 and the electrode 800 are formed on one side of the substrate 100 and the electrodes 901, 902, 903 function as a reflection film, is called a flip chip. Electrodes 901,902 and 903 may be formed of a highly reflective electrode 901 (e.g., Ag), an electrode 903 (e.g., Au) for bonding, and an electrode 902 (not shown) to prevent diffusion between the electrode 901 material and the electrode 903 material. For example, Ni). Such a metal reflection film structure has a high reflectance and an advantage of current diffusion, but has a disadvantage of light absorption by a metal.

2 is a view showing an example of a semiconductor light emitting device disclosed in Japanese Laid-Open Patent Publication No. 2006-20913.

The semiconductor light emitting device includes a substrate 100, a buffer layer 200 grown on the substrate 100, an n-type semiconductor layer 300 grown on the buffer layer 200, an active layer 400 grown on the n-type semiconductor layer 300, A p-type semiconductor layer 500 formed on the active layer 400 and a p-type semiconductor layer 500 formed on the p-type semiconductor layer 500 and formed on the transparent conductive film 600, A bonding pad 700 and an n-side bonding pad 800 formed on the n-type semiconductor layer 300 exposed by etching. A DBR (Distributed Bragg Reflector) 900 and a metal reflection film 904 are provided on the transmissive conductive film 600. According to this structure, although the absorption of light by the metal reflection film 904 is reduced, the current diffusion is less smooth than that using the electrodes 901, 902, and 903. Further, there is a disadvantage in that a part of the light distribution Bragg reflector is transmitted through a region where the reflectance is lowered due to the height difference and is lost.

This will be described later in the Specification for Implementation of the Invention.

SUMMARY OF THE INVENTION Herein, a general summary of the present disclosure is provided, which should not be construed as limiting the scope of the present disclosure. of its features).

According to one aspect of the present disclosure, in a semiconductor light emitting device, a first semiconductor layer having a first conductivity, a second semiconductor layer having a second conductivity different from the first conductivity, A plurality of semiconductor layers interposed between the first semiconductor layer and the second semiconductor layer and having an active layer that generates light through recombination of electrons and holes; A first electrode portion that is in electrical communication with the first semiconductor layer and supplies one of electrons and holes; A second electrode portion that is in electrical communication with the second semiconductor layer and supplies the remaining one of electrons and holes; A non-conductive reflective film formed on the plurality of semiconductor layers so as to reflect light generated in the active layer toward the first semiconductor layer, the non-conductive reflective film having an opening formed therein; And an additional reflective film formed on the non-conductive reflective film so as to reflect the light transmitted through the non-conductive reflective film toward the first semiconductor layer, wherein at least one of the first and second electrode parts comprises: A lower electrode electrically connected to the plurality of semiconductor layers; And a connection electrode formed between the non-conductive reflective film and the additional reflective film and electrically connected to the lower electrode through the opening.

This will be described later in the Specification for Implementation of the Invention.

1 is a view showing an example of a semiconductor light emitting device disclosed in U.S. Patent No. 7,262,436,
2 is a view showing an example of a semiconductor light emitting device disclosed in Japanese Laid-Open Patent Publication No. 2006-20913,
3 is a view for explaining an example of a semiconductor light emitting device according to the present disclosure,
4 is a view for explaining an example of a portion where light is likely to be transmitted from a non-conductive reflective film,
5 is a view for explaining another example of the semiconductor light emitting device according to the present disclosure,
6 to 17 are views for explaining an example of a method of manufacturing a semiconductor light emitting device according to the present disclosure;

The present disclosure will now be described in detail with reference to the accompanying drawings.

3 is a view for explaining an example of a semiconductor light emitting device according to the present disclosure. In this example, a semiconductor light emitting device includes a substrate 10, a plurality of semiconductor layers, a light absorption preventing film 41, a current diffusion conductive film 60, A non-conductive reflective film 91, an additional reflective film 95, first electrode portions 71, 72, 74, and 75, and second electrode portions 81, 82, 84, and 85. Hereinafter, a group III nitride semiconductor light emitting device will be described as an example.

The substrate 10 is mainly made of sapphire, SiC, Si, GaN or the like, and the substrate 10 can be finally removed. 3, the first electrode units 71, 72, 74, and 75 and the second electrode units 81, 82, 84, and 85 are all disposed on the opposite sides of the substrate with respect to the plurality of semiconductor layers. This example can also be applied to a semiconductor light emitting element from which a substrate is removed. For example, this example may be applied to a semiconductor light emitting device in which an n-side bonding electrode is located below a first semiconductor layer exposed by removing a substrate as a vertical semiconductor light emitting device.

The plurality of semiconductor layers includes a buffer layer 20 formed on the substrate 10, a first semiconductor layer 30 having a first conductivity (e.g., Si-doped GaN) 30, a second semiconductor layer 30 having a second conductivity different from the first conductivity, (For example, Mg-doped GaN) 50 and an active layer 40 (e.g., InGaN / (GaN)) interposed between the first semiconductor layer 30 and the second semiconductor layer 50 and generating light through recombination of electrons and holes In) GaN multiple quantum well structure). Each of the plurality of semiconductor layers 30, 40, and 50 may have a multi-layer structure, and the buffer layer 20 may be omitted.

The non-conductive reflective film 91 reflects light from the active layer 40 toward the plurality of semiconductor layers 30, 40, and 50. In this example, the non-conductive reflective film 91 is formed of a non-conductive material for reducing light absorption by the metal reflective film. The non-conductive reflective film 91 may be composed of a single dielectric layer or may have a multilayer structure. In one example of the multilayer structure, the non-conductive reflective film 91 may include a sequentially stacked dielectric film, a first distributed Bragg reflector, and a clad film.

The first electrode portions 71, 72, 74, and 75 are electrically connected to the first semiconductor layer 30 to supply electrons and holes, and the second electrode portions 81, 2 semiconductor layer 50 and supplies the remaining one of electrons and holes.

The additional reflective film 95 is formed on the non-conductive reflective film 91 so as to reflect the light transmitted through the non-conductive reflective film 91 to the first semiconductor layer 30 side. At least one of the first electrode units 71, 72, 74, 75 and the second electrode units 81, 82, 84, 85 is connected to the lower electrodes 71, 81 and the connection electrodes 72, 74, . The lower electrodes 71 and 81 are at least partially exposed by the openings 62 and 63 formed in the nonconductive reflective film 91 and are electrically connected to the plurality of semiconductor layers 30, The connection electrodes 72, 74, 82 and 84 are formed on the nonconductive reflective film 91 and are electrically connected to the lower electrodes 71 and 81 through the openings 62 and 63, respectively. For example, a plurality of openings 62 and 63 are formed in the non-conductive reflective film 91 to facilitate current supply, and the first connection electrodes 72 and 74 are formed in a plurality of openings And the second connection electrodes 82 and 84 connect the other plurality of openings 62 communicating with the second semiconductor layer 50. [ The openings 62 and 63 include openings not only on the upper side but also on the side surfaces of the semiconductor light emitting device.

A further reflective film 95 is formed on the non-conductive reflective film 91 and covers the connecting electrodes 72, 74, 82, 84. The light generated from the active layer 40 by the non-conductive reflective film 91 is reflected to the side of the plurality of semiconductor layers 30, 40 and 50, but a part of the light may pass through or leak through the non-conductive reflective film 91 . The additional reflective film 95 reflects the light transmitted through the non-conductive reflective film 91 toward the plurality of semiconductor layers 30, 40 and 50, thereby reducing light loss and improving brightness of the semiconductor light emitting device.

Several means for supplying electrons or holes to the connecting electrodes 72, 74, 82, 84 may be considered. For example, at least one of the first electrode portion and the second electrode portion (an electrode having a lower electrode and a connection electrode) may include upper electrodes 75 and 85. The upper electrodes 75 and 85 are formed on the additional reflective film 95 and are electrically connected to the connecting electrodes 72, 74, 82 and 84 through openings 64 and 65 formed in the additional reflective film 95 . The openings 64 and 65 include openings not only on the upper side but also on the side of the semiconductor light emitting device.

In this example, the first electrode portion and the second electrode portion have lower electrodes 71 and 81, connection electrodes 72, 74, 82, and 84, and upper electrodes 75 and 85, respectively. The lower electrode 71 (first lower electrode) of the first electrode portion is in contact with the exposed first semiconductor layer 30 by partially removing the plurality of semiconductor layers 30, 40, and 50. A lower electrode 81 (second lower electrode) of the second electrode portion is provided on the second semiconductor layer 50. For example, the first lower electrode 71 and the second lower electrode 81 are formed in a plurality of island shapes in a substantially uniform manner on the light emitting surface (plane when the semiconductor layers 30, 40, 50 are observed from above) , Or symmetrically arranged. Alternatively, at least one of the first lower electrode 71 and the second lower electrode 81 may extend in a strip shape.

A part of the light generated in the active layer 40 may be absorbed by the second lower electrode 81. In order to prevent this, preferably, a light absorption prevention film 41 is provided under the second lower electrode 81 do. The light absorption preventing film 41 may have a function of reflecting a part or all of the light generated in the active layer 40 and may have a function of reflecting a current immediately below the second lower electrode 81 from the second lower electrode 81 It may have only the function of not allowing it to flow, and it may have both functions of both.

Preferably, a current diffusion conductive film 60 is provided. The current diffusion conductive film 60 is formed between the light absorption prevention film 41 and the second lower electrode 81 and has a light transmitting property and may be formed to cover the entire second semiconductor layer 50 as a whole. In particular, in the case of p-type GaN, the current diffusion ability is lowered. When the p-type semiconductor layer 50 is made of GaN, most of the current diffusion conductive film 60 should be assisted. For example, a material such as ITO or Ni / Au can be used as the current diffusion conductive film 60.

4 is a view for explaining an example of a portion where light is likely to be transmitted from the non-conductive reflective film 900. The structures (for example, electrodes 700 and 800, steps, etc.) under the non- The conductive reflection film 900 has portions (indicated by dotted lines) where a height difference occurs. The non-conductive reflective film 900 may have a distributed Bragg reflector. The distributed Bragg reflector can be composed of multiple layers of material, and each layer of material must be well-formed to a specially designed thickness to function as a reflective film.

For example, the distributed Bragg reflector may be composed of repeated lamination of SiO ₂ / TiO ₂ , SiO ₂ / Ta ₂ O ₂ , or SiO ₂ / HfO, and for blue light, SiO ₂ / TiO ₂ has good reflection efficiency , And SiO ₂ / Ta ₂ O ₂ or SiO ₂ / HfO for UV light may have good reflection efficiency. However, the non-conductive reflective film 900 may not partially reflect incident light but may partially transmit the incident light. In particular, as illustrated in FIG. 4, the regions 700 and 800 below the non-conductive reflective film 900 and the regions where each material layer of the non-conductive reflective film 900 is difficult to be formed with a designed thickness due to a step (indicated by a dotted line) In this region, the reflection efficiency is lowered and the lights L11 and L12 can be transmitted.

3, the additional reflective film 95 reflects the light transmitted through the non-conductive reflective film 91 toward the plurality of semiconductor layers 30, 40, and 50 to reduce the light loss and reduce the luminance of the semiconductor light- Improvement. For example, the additional reflective film 95 may be formed of a non-metallic material or a non-conductive material to reduce light absorption, and may be formed of a single dielectric film, but it is preferable that the additional reflective film 95 has a multilayer structure in order to increase reflectance. In one example of a multi-layer structure, the additional reflective film 95 may include a second distributed Bragg reflector 95a. The additional reflecting film 95 is provided between the second distributed Bragg reflector 95a and the nonconductive reflecting film 91 and between the lower dielectric film 95b and the second distributed Bragg reflector 95a and the upper electrodes 75, Of the upper dielectric film 95c. The lower dielectric film 95b covers the connection electrodes 72, 74, 82, and 84, thereby alleviating the height difference. A second distributed Bragg reflector (95a) is a light-transmitting material to prevent absorption of light; may be formed (for example, SiO ₂ / TiO _2). The lower dielectric film 95b and the upper dielectric film 95c may be formed of a material having a lower refractive index than that of the second distributed Bragg reflector 95a so that the additional reflective film 95 has a waveguide structure . The lower dielectric film 95b contacts the connection electrodes 72, 74, 82, and 84, and is preferably selected as a material having good bonding strength with the connection electrodes 72, 74, 95c are preferably selected from materials having good bonding strength with the upper electrodes 75, 85.

The present disclosure does not exclude that the additional reflective film 95 is formed of a metal film. In this case, the additional reflective film 95 is preferably formed avoiding the portion where the opening is to be formed, and can be electrically insulated by the lower dielectric film 95b and the upper dielectric film 95c. It is also possible to form the additional reflecting film 95 only partially, for example, only in a specific region of the non-conductive reflecting film 91 (for example, a step or a region with a large height difference).

The upper electrode 75 (the first upper electrode) of the first electrode portion and the upper electrode 85 (the second upper electrode) of the second electrode portion are provided on the additional reflective film 95. For example, the first upper electrode 75 and the second upper electrode 85 are disposed opposite to each other, and through the openings formed in the additional reflective film 95, the first connection electrodes 72, 74 and the second connection electrodes 72, And is electrically connected to the connection electrodes 82 and 84. Electrons are supplied to the first semiconductor layer 30 through the first upper electrode 75 and the first connection electrodes 72 and 74 and the first lower electrode 71 and electrons are supplied to the second upper electrode 85 and second Holes are supplied to the second semiconductor layer 50 through the connection electrodes 82, 84 and the second lower electrode 81. The first upper electrode 75 and the second upper electrode 85 may be electrodes for eutectic bonding or soldering electrodes.

The semiconductor light emitting element reduces the light absorption by using the non-conductive reflective film 91 instead of the metal reflective film. The connection electrodes 72, 74, 82, 84 and the lower electrodes 71, 81 through the plurality of openings 62, 63 formed in the non-conductive reflective film 91 to form the plurality of semiconductor layers 30, 40, 50). Accordingly, it is not necessary to form a metal strip on the first semiconductor layer 30 and / or the second semiconductor layer 50 as long as the branch electrodes for current diffusion, or it is sufficient to form a small number of water, The light absorption by the metal is further reduced. Further, even the light transmitted through the non-conductive reflective film 91 is reflected by the additional reflective film 95, contributing to the improvement of the luminance.

On the other hand, when the first connecting electrodes 72 and 74 and the second connecting electrodes 82 and 84 contact the first semiconductor layer 30 or the current diffusion conductive film 60 directly through the openings 62 and 63 The first lower electrode 71 and the second lower electrode 81 are electrically connected to the connection electrodes 72, 74, 82, 84 and the first semiconductor layer 30 and the current diffusion conductive film 60 ) (E.g., reduced contact resistance). In addition, when the openings 62 and 63 are formed in the non-conductive reflective film 91, the upper surfaces of the lower electrodes 71 and 81 may be influenced and the electrical contact may be deteriorated. In order to prevent this, the lower electrodes 71 and 81 are sequentially laminated with a contact layer / reflective layer / diffusion preventing layer / oxidation preventing layer / etching preventing layer. The etching preventing layer protects the etching And after the formation of the openings 62 and 63, the etch stop layer is removed by wet etching to expose the antioxidant layer, so that the connection electrodes 72, 74, 82, and 84 are brought into contact with the antioxidant layer. Similarly, in the process of forming the openings 64 and 65 in the additional reflective film 95, the connection electrodes 72, 74, 82 and 84 are partially exposed to the openings 64 and 65, 82 and 84 may be influenced by the process of forming the openings 64 and 65. [ Accordingly, it is also conceivable to form the uppermost layer of the connection electrodes 72, 74, 82, and 84 as a multi-layer structure including the etching prevention layer similarly to the lower electrodes 71 and 81.

5 is a diagram showing another example of the semiconductor light emitting device according to the present disclosure. The semiconductor light emitting device includes a substrate 10, a plurality of semiconductor layers, a light absorption preventing film 41, a current diffusion conductive film 60, An additional reflective film 95, first electrode portions 71, 72, 74, and 75, and second electrode portions 81, 82, 84, and 85. In this example, the non-conductive reflective film 91 includes a dielectric film 91b, a first distributed Bragg reflector 91a, and a clad film 91c. The additional reflective film 95 includes a dielectric film 95b, a second distributed Bragg reflector 95a, and a clad film 95c.

According to this embodiment, in forming the semiconductor light emitting device, the first lower electrode 71 is formed with a mesa etched groove 61 to expose the first semiconductor layer 30 in contact therewith, And the height difference is generated due to the same structure as the lower electrodes 71 and 81. Also, the height difference is caused by the connecting electrodes 72, 74, 82, and 84 on the non-conductive reflective film 91. Therefore, it is possible to stably manufacture the distributed Bragg reflectors 91a and 95a by forming the dielectric films 91b and 95b of a certain thickness prior to the deposition of the distributed Bragg reflectors 91a and 95a, which require precision, It can also help in the reflection of light.

SiO ₂ is suitable as the material of the dielectric films 91b and 95b, and the thickness thereof is preferably 0.2 um to 1.0 um. If the thickness of the dielectric films 91b and 95b is too thin, it may be insufficient to cover the lower electrodes 71 and 81 having a height of about 2 to 3 micrometers. When the dielectric films 91 and 95 are too thick, , 65) may be burdensome. The thickness of the dielectric films 91b and 95b may be thicker than the thickness of the subsequent distributed Bragg deflectors 91a and 95a. It is also necessary to form the dielectric films 91b and 95b by a method more suitable for ensuring reliability of devices. For example, the dielectric films 91b and 95b made of SiO ₂ are preferably formed by CVD (Chemical Vapor Deposition), in particular, plasma enhanced chemical vapor deposition (PECVD). This is because chemical vapor deposition is more advantageous than physical vapor deposition (PVD) such as electron beam evaporation (E-Beam Evaporation) in step coverage. Specifically, when the dielectric films 91b and 95b are formed by E-Beam Evaporation, the dielectric films 91b and 95b are difficult to be formed in the designed thickness in the height difference region. As a result, As described above, the reflectance of light may be lowered, and electrical insulation may also be a problem. Therefore, it is preferable that the dielectric films 91b and 95b are formed by a chemical vapor deposition method in order to reduce the height difference and secure insulation. Therefore, it is possible to secure the functions of the reflective films 91 and 95 while ensuring the reliability of the semiconductor light emitting device.

The distributed Bragg reflectors 91a and 95a are formed on the dielectric films 91b and 95b, respectively. For example, when the distributed Bragg reflectors 91a and 95a are made of a repetitive layer structure of TiO ₂ / SiO ₂ , the distributed Bragg reflectors 91a and 95a are formed by physical vapor deposition (PVD) E-Beam Evaporation, Sputtering, or Thermal Evaporation.

At least one of the dielectric films 91b and 95b or at least one of the clad films 91c and 95c may be omitted. Distributed Bragg reflector (91a, 95a) is a light-transmitting material to prevent absorption of light; may be formed (for example, SiO ₂ / TiO _2). The dielectric films 91b and 95b may be made of a dielectric material (for example, SiO ₂ ) whose refractive index is smaller than the effective refractive index of the distributed Bragg reflectors 91a and 95a. Here, the effective refractive index means an equivalent refractive index of light that can travel in a waveguide made of materials having different refractive indices. May be made _{of: (Al 2 O 3, SiO} 2, SiON, MgF, CaF example) a clad layer (91c, 95c) also distributed Bragg reflector (91a, 95a) than the effective refractive index of the low material. When the refractive index is selected, the dielectric film 91b-the first distributed Bragg reflector 91a-the clad film 91c, and the dielectric film 95b-the first distributed Bragg reflector 95a-the clad film 95c, Can be described in terms of an optical waveguide. The optical waveguide is a structure for guiding light by surrounding the propagating portion of the light with a material having a lower refractive index than that of the light guiding portion. From this point of view, the dielectric Bragg reflectors 91a and 95a can be regarded as a part of the waveguide as a constitution surrounding the waveguide 91b and 95b and the clad films 91c and 95c.

FIGS. 6 to 17 are views for explaining an example of a method of manufacturing a semiconductor light emitting device according to the present disclosure, and cross-sections (FIGS. 9, 11, and 16) are examples of cross sections taken along the line AA in FIG. 17) to be. First, a plurality of semiconductor layers 30, 40, 50 are grown on a substrate 10. For example, as illustrated in Figure 6 and 9, the substrate, the semiconductor layer is not doped with: (AlN or GaN buffer layer for example) (for example, (10 Yes Al ₂ O _3, Si, SiC) on the buffer layer un doped GaN), a first semiconductor layer 30 (e.g., Si-doped GaN) having a first conductivity, an active layer 40 (InGaN / (In) GaN multiple quantum well structure ), A second semiconductor layer 50 (e.g., Mg-doped GaN) having a second conductivity different from the first conductivity is grown. The buffer layer 20 may be omitted, and each of the plurality of semiconductor layers 30, 40, and 50 may have a multi-layer structure. Although the first semiconductor layer 30 and the second semiconductor layer 50 can be formed by reversing the conductivity, it is not preferable in the case of the III-nitride semiconductor light emitting device.

Next, a light absorption prevention film 41 is formed on the second semiconductor layer 50 by using SiO ₂ , TiO ₂ or the like. The light absorption prevention film 41 may be formed to have a width slightly larger than that of the second lower electrode 81 at a position corresponding to the second lower electrode 81 to be formed later. It is preferable that the light absorption preventing film 41 is uniformly distributed over the entire light emitting surface. In consideration of the fact that the current diffusion is relatively poor in p-GaN (for example, Mg-doped GaN) Since the light is distributed from the edge to the inside of the device, the light absorption prevention film 41 can be formed accordingly. In this example, the light absorption preventing film 41 is formed in a plurality of island shapes. As another example, if the second lower electrode 81 is formed in a long band shape in the form of a branch electrode, the light absorption prevention film 41 may also be formed in a strip shape.

Thereafter, as shown in FIG. 7, a current diffusion conductive film 60 is formed on the second semiconductor layer 50 by using a light-transmitting material having good conductivity such as ITO to cover the light absorption prevention film 41. Next, the second semiconductor layer 50 and the active layer 40 are mesa-etched to form a plurality of grooves 61 exposing the first semiconductor layer 30. Next, as shown in FIG. The plurality of grooves 61 are arranged in an island shape. In this embodiment, since the first lower electrodes 71 are arranged in a plurality of island shapes, a plurality of grooves 61 are formed accordingly. As another example, if the first lower electrode 71 is formed in a long band shape in the form of a branch electrode, the light absorption prevention film 41 may also be formed in a strip shape.

8 and 9, a first lower electrode 71 is formed on the first semiconductor layer 30 exposed in the plurality of grooves 61 through a deposition method or the like, and a light absorption prevention film The second lower electrode 81 is formed on the current diffusion conductive film 60 corresponding to the second electrode 41. [ When the first lower electrode 71 and the second lower electrode 81 are made of the same material, the first lower electrode 71 and the second lower electrode 81 may be formed first, As shown in Fig. The second lower electrode 81 is formed to have a width smaller than that of the light absorption prevention film 41 and the first lower electrode 71 is formed to have a width smaller than the width of the groove 61, Away from the side.

Next, as shown in FIGS. 10 and 11, a non-conductive reflective film 91 is formed on the current diffusion conductive film 60. For example, the dielectric film 91b covering the current diffusion conductive film 60, the first distributed Bragg reflector 91a, and the clad film 91c are formed. The dielectric film 91b or the clad film 91c may be omitted. A first distributed Bragg reflector (91a) is, for example, pairs of SiO ₂ and TiO ₂ are laminated is made a plurality of times. The addition may be made by combination of the first distributed Bragg reflector (91a) is a _{Ta 2 O 5, HfO, ZrO} , SiN , such as high refractive index material than the low dielectric thin film (typically, SiO ₂₎ refractive index. When the first distributed Bragg reflector 91a is made of TiO ₂ / SiO ₂ , the optimization process is performed based on the optical thickness of 1/4 of the wavelength of the light emitted from the active layer 40, considering the incident angle and the reflectance depending on the wavelength , And it is not necessary that the thickness of each layer necessarily keep the optical thickness of 1/4 of the wavelength. The number of combinations is 4 to 40 pairs.

It is preferable that the effective refractive index of the first distributed Bragg reflector 91a is larger than the refractive index of the dielectric film 91b for light reflection and guidance. If the first distributed Bragg reflector (91a) is composed of SiO ₂ / TiO _2, the refractive index of SiO ₂ is 1.46, since the refractive index of TiO ₂ is 2.4, the effective refractive index in the distributed Bragg reflector has a value between 1.46 and 2.4 I have. Therefore, the dielectric film 91b may be made of SiO ₂ , and the thickness thereof is suitably from 0.2 탆 to 1.0 탆. By forming the dielectric film 91b having a certain thickness prior to the deposition of the first distributed Bragg reflector 91a requiring precision, the first distributed Bragg reflector 91a can be stably manufactured and also helps to reflect light .

A clad layer (91c) may be formed of a dielectric film (91b), material of MgF, CaF, such as a metal oxide, SiO _2, SiON, such as Al ₂ O _3. The clad film 91c may also be formed of SiO ₂ having a refractive index of 1.46 which is smaller than the effective refractive index of the first distributed Bragg reflector 91a. It is preferable that the clad film 91c has a thickness of lambda / 4n to 3.0 um. Where lambda is the wavelength of the light generated in the active layer 40 and n is the refractive index of the material forming the clad film 91c. and 4500/4 * 1.46 = 771A or more when? is 450 nm (4500 A).

Considering that the uppermost layer of the distributed Bragg reflector 91a composed of a large number of pairs of SiO ₂ / TiO ₂ may be TiO ₂ , but considering that it can be made of an SiO ₂ layer having a thickness of λ / 4n, Is preferably thicker than? / 4n so as to be differentiated from the uppermost layer of the distribution Bragg reflector 91a located below. However, it is not only burdensome to the subsequent opening forming process, but also increases the thickness because the cladding film 91c can increase the material cost without contributing to the improvement of the efficiency. Therefore, in order not to burden the subsequent process, it is appropriate that the maximum value of the thickness of the clad film 91c is formed within 1 mu m to 3 mu m. However, in some cases it is not impossible to form more than 3.0 μm.

When the first distribution Bragg reflector 91a directly contacts the first connection electrodes 72 and 74 and the second connection electrodes 82 and 84, a part of light traveling through the first distribution Bragg reflector 91a Can be absorbed by the first connecting electrodes (72, 74) and the second connecting electrodes (82, 84). Therefore, when the clad film 91c having a refractive index lower than that of the first distributed Bragg reflector 91a is introduced as described above, light absorption by the first connection electrodes 72, 74 and the second connection electrodes 82, Can be greatly reduced.

The dielectric film 91b may be omitted from the viewpoint of the entire technical idea of the present disclosure, and the first distributed Bragg reflector 91a and the clad film 91c may be omitted There is no reason to exclude the configuration. It may be considered to include a dielectric film 91b made of TiO ₂ which is a dielectric instead of the first distributed Bragg reflector 91a. It is also conceivable to omit the clad film 91c when the first distributed Bragg reflector 91a has the SiO ₂ layer as the uppermost layer. If the dielectric film 91b and the first distribution Bragg reflector 91a are designed in consideration of the reflectance of light traveling substantially in the transverse direction, the first distribution Bragg reflector 91a is provided with the TiO ₂ layer as the uppermost layer The case of omitting the clad film 91c will also be considered.

Thus, the dielectric film 91b, the first distributed Bragg reflector 91a, and the clad film 91c serve as a non-conductive reflective film 91 as a waveguide, and preferably have a total thickness of 1 to 8 um .

12 is a view for explaining an example of the opening forming process. As described above, the non-conductive reflective film 91 is formed on the current diffusion conductive film 60, and the opening (not shown) is formed through the etching process 62, 63). The openings 62 and 63 do not preclude the form of opening to the side of the semiconductor light emitting element as well as to the side.

As the etching process proceeds, openings 62 and 63 (see FIGS. 10 and 12) are gradually formed as shown in FIG. 12 (a), and as shown in FIG. 12 (b) A part of the upper surface is exposed. The same process can be performed on the first lower electrode 71 as well. 12A, the height difference between the upper rim of the openings 62 and 63 and the upper surface of the non-conductive reflective film 91 is reduced in FIG. 12B. 12 (c), the periphery of the second lower electrode 81 is exposed by the opening 62, and the non-conductive reflective film 91 is formed with the inclined surface due to the opening 62. [ The first lower electrode 71 and the second lower electrode 81 are exposed by the openings 62 and 63. The width of the openings 62 and 63 may be selected to expose the periphery of the lower electrodes 71 and 81 as required, as shown in FIG. 12D, or may be selected to expose only a part of the lower electrodes 71 and 81 as shown in FIG. 12B . As shown in FIG. 12D, the periphery of the openings 62 and 63 is exposed and the connecting electrodes 72, 74, 82 and 84 surround the lower electrodes 71 and 81, The stability of the electrical connection can be further improved. Further, the connection between the lower electrodes 71 and 81 and the connection electrodes 72, 74, 82 and 84 can be further strengthened and stabilized through the heat treatment.

Fig. 13 is a view for explaining an example of the layer structure of the lower electrodes 71 and 81, and enlarged a part of the openings 62 and 63 formed by the dry etching process.

(For example, CF ₄ , C ₂ F ₆ , C ₃ F ₈ , SF _6, etc.) containing an F group by an etching gas in the dry etching process (first etching process) for forming the openings 62 and 63 described above, Can be used. The lower electrodes 71 and 81 may include a plurality of layers. For example, the second lower electrode 81 includes a contact layer 81a electrically connected to the p-type semiconductor layer 50, an oxidation preventing layer 81d and an oxidation preventing layer 81d formed on the contact layer 81a, And an etch stopping layer 81e formed on the substrate. The second lower electrode 81 includes a contact layer 81a, a reflection layer 81b, a diffusion prevention layer 81c, an oxidation prevention layer 81d, and an etching prevention layer 81e sequentially formed on the light transmissive conductive film 60 . The first lower electrode 71 may have the same or similar layer structure as the second lower electrode 81.

The contact layer 81a is preferably made of a material which makes good electrical contact with the light-transmitting conductive film 60. As the contact layer 81a, materials such as Cr and Ti are mainly used, and Ni, TiW and the like can be used, and Al and Ag having good reflectance can be used. The reflective layer 81b may be made of a metal having a high reflectivity (for example, Ag, Al, or a combination thereof). The reflective layer 81b reflects light generated in the active layer 40 toward the plurality of semiconductor layers 30, 40, and 50. The reflective layer 81b may be omitted. The diffusion preventive layer 81c prevents the material of the reflection layer 81b or the material of the oxidation preventive layer 81d from diffusing into another layer. The diffusion preventive layer 81c may be made of at least one selected from Ti, Ni, Cr, W and TiW, and Al and Ag may be used when a high reflectance is required. The oxidation preventing layer 81d may be made of Au, Pt, or the like, and may be any material as long as it is exposed to the outside and is in contact with oxygen and is not easily oxidized. As the oxidation preventing layer 81d, Au having good electric conductivity is mainly used.

The etching preventing layer 81e is a layer exposed in a dry etching process for forming the openings 62 and 63. In this example, the etching preventing layer 81e is the uppermost layer of the second lower electrode 81. [ When Au is used as the etch stop layer 81e, not only the bonding strength with the non-conductive reflective film 91 is weak, but a part of Au may be damaged or damaged at the time of etching. Therefore, if the etch stopping layer 81e is made of a material such as Ni, W, TiW, Cr, Pd, or Mo instead of Au, bonding strength with the non-conductive reflective film 91 can be maintained and reliability can be improved.

On the other hand, in the dry etching process, the etching preventive layer 81e protects the second lower electrode 81, and in particular, prevents the oxidation preventing layer 81d from being damaged. For the dry etching process, a halogen gas (eg, CF ₄ , C ₂ F ₆ , C ₃ F ₈ , or SF ₆ ) containing an F group may be used as an etching gas. Therefore, in order to prevent damage to the oxidation preventing layer 81d, it is preferable that the etching preventing layer 81e is made of a material having an excellent etching selectivity in this dry etching process. If the etch selectivity of the etch stop layer 81e is poor, the oxidation preventive layer 81d may be damaged or damaged in the dry etching process. Therefore, Cr or Ni is suitable as the material of the etch stopping layer 81e from the viewpoint of etching selectivity. Ni or Cr reacts with or does not react with the etching gas in the dry etching process, and protects the second lower electrode 81 without being etched.

On the other hand, in the dry etching process for forming the openings 62 and 63, a material such as an insulating material or an impurity may be formed on the upper portion of the second lower electrode 81 due to the etching gas. For example, the halogen etch gas including the F group may react with the upper layer metal of the electrode to form a material. For example, at least some of Ni, W, TiW, Cr, Pd, Mo, etc. as a material of the etch stop layer 81e may react with the etching gas in the dry etching process to form a material 107 (e.g., NiF) have. The material thus formed may cause a decrease in the electrical characteristics of the semiconductor light emitting device (for example, an increase in the operating voltage). A part of Ni, W, TiW, Cr, Pd, or Mo as a material of the etch stopping layer 81e reacts with the etching gas to form a very small amount of material. It is preferable that the material is inhibited from forming or a small amount is formed. From this point of view, Cr is more suitable for the material of the etch stopping layer 81e than Ni.

The upper layer of the lower electrode 81, that is, the portion corresponding to the openings 62 and 63 of the etch stopping layer 81e is removed by a wet etching process (second etching process) 13, the oxidation preventing layer 81d corresponding to the openings 62 and 63 is exposed. The material is etched away together with the etch stop layer 81e. As described above, electrical contact between the lower electrodes 71, 81, and 93 and the connecting electrodes 72, 74, 82, and 84 is improved and the electrical characteristics of the semiconductor light emitting device are prevented from being degraded.

On the other hand, the first etching process may be performed by wet etching to form the openings 62 and 63. In this case, HF, BOE, NH ₃ , HCl, and the like may be used alone or in combination of appropriate concentrations as the etchant of the non-conductive reflective film 91. When the openings 62 and 63 are formed in the non-conductive reflective film 91 by the wet etching process as in the above-described dry etching process, the etching selectivity ratio of the etch stopping layer 81e is excellent for protecting the oxidation preventing layer 81d desirable. From this point of view, Cr is suitable as a material for the etch stopping layer 81e. Thereafter, the etch stop layer 81e corresponding to the openings 62 and 63 can be removed by another subsequent wet etching process (second etching process).

Next, as shown in FIGS. 11 and 14, the first connection electrodes 72 and 74 and the second connection electrode (not shown) are formed on the non-conductive reflective film 91 by using a sputtering equipment, an E- 82, 84 are deposited. A part 63 of the plurality of openings 62 and 63 communicates with the plurality of grooves 61 exposing the first semiconductor layer 30 and the remaining openings 62 are formed on the current diffusion conductive film 60 The second lower electrode 81 is exposed. The first connection electrodes 72 and 74 and the second connection electrodes 82 and 84 are electrically connected to the first lower electrode 71 and the second lower electrode 81 through a plurality of openings 62 and 63, do. The first connection electrodes 72 and 74 and the second connection electrodes 82 and 84 may include a contact layer and a reflective layer. For example, the first and second connection electrodes 71 and 81, A contact layer may be formed using Cr, Ti, Ni, or an alloy thereof for stable electrical contact, and a reflective layer may be formed on the contact layer using a reflective metal layer such as Al or Ag. Alternatively, in the process of forming the openings 64 and 65 (see FIG. 17) in the additional reflective film 95 to be described later as in the process of forming the openings 62 and 63 for exposing the lower electrodes 71 and 81, The top layer of the connection electrodes 72, 74, 82, 84 exposed to the openings 64, 65 may be adversely affected by electrical contact. Therefore, the connection electrodes 72, 74, 82 and 84 may have a multilayer structure like the lower electrodes 71 and 81, for example, a contact layer / a reflection layer / a diffusion prevention layer / an oxidation prevention layer / These may be selected from the above-mentioned materials of the lower electrodes 71 and 81, respectively.

The shapes and patterns of the connecting electrodes 72, 74, 82, and 84 can be variously changed. Preferably, the first connecting electrodes 72 and 74 are formed to connect the plurality of openings 63 to connect the first lower electrode 71, which is uniformly disposed over the entire light emitting surface. The second connection electrodes 82 and 84 are formed so as to connect the plurality of openings 62 to connect the second lower electrode 81 uniformly disposed on the entire light emitting surface. In this example, at least one of the first connection electrodes 72 and 74 and the second connection electrodes 82 and 84 is formed in a closed loop shape on the non-conductive reflective film 91 so that current uniformity across the light- . Here, the closed loop shape is not limited to the complete closed loop shape but includes a partially closed loop shape. A closed second outside connection second connection electrode 82 and an inside second connection electrode 84 and a closed first outside connection electrode 72 between the inside and outside second connection electrodes 82 and 84, An inner first connecting electrode 74 is further provided inside the inner second connecting electrode 84 and a central protrusion 85 protrudes from the inner second connecting electrode 84 to form an inner first And extend to the inside of the connection electrode 74.

In this way, the closed-loop connecting electrodes 72, 74, 82, and 84 connect the plurality of openings 62 and 63 and supply the uniform current through the openings 62 and 63, It is very advantageous to improve the uniformity of the current supply and consequently the uniformity of the current density in the light emitting surface since it is generally uniform or symmetrical.

Alternatively, the openings 63 of the first lower electrode 71 may be connected to the first connection electrodes of a stripe shape or a finger shape, respectively, and the first connection electrodes may be formed in a stripe shape, It is also possible to arrange the second connection electrodes in the form of fingers to connect the openings 62 of the second lower electrode 81 side. It is also possible to form the first connecting electrode and the second connecting electrode in the form of fingers interdigitated with each other. In addition, the shapes of the first connection electrode and the second connection electrode can be variously changed.

Next, as shown in FIGS. 15 and 16, an additional reflective film 95 is formed on the non-conductive reflective film 91. An additional reflective film 95 is formed to cover the first connection electrodes 72 and 74 and the second connection electrodes 82 and 84. The additional reflective film 95 reflects the light transmitted through the non-conductive reflective film 91 to the side of the plurality of semiconductor layers 30, 40, 50 to improve the brightness. Additional reflective film 95 is a single insulating layer (for example: SiO _2, SiN, TiO _2, Al ₂ O _3, Su-8, etc.) to be made possible, but, more reflective layer to increase the reflectivity of the second distributed Bragg It is preferable to provide a reflector 95a. The second distributed Bragg reflector 95a may have a smaller thickness than the first distributed Bragg reflector 91a. The additional reflective film 95 includes a lower dielectric film 95b for reducing the height difference between the nonconductive reflective film 91 and the second distributed Bragg reflector 95a, An upper dielectric film 95c may be provided between the Bragg reflectors 95a. In particular, the refractive index of the upper dielectric film 95c can be made smaller than the refractive index of the second distributed Bragg reflector 95a, so that the amount of light absorbed by the upper electrodes 75 and 85 can be reduced.

Thereafter, a plurality of additional reflective film side openings 64 and 65 are formed in the additional reflective film 95. [ In the process of forming the additional reflection film side openings 64 and 65, a dry etching method similar to the formation of the openings 64 and 65 is used in the nonconductive reflective film 91. At this time, The top surfaces of the exposed connection electrodes 72, 74, 82, and 84 may be affected by dry etching, and the electrical contact may be deteriorated. As described above, the connecting electrodes 72, 74, 82, and 84 may also have a multi-layer structure, such as a contact layer / reflective layer / diffusion barrier / antioxidant / have. For example, as the contact layer, materials such as Cr and Ti are mainly used, and Ni, TiW and the like can be used, and Al and Ag having high reflectance can be used. The reflective layer may be made of a metal having a high reflectance (e.g., Ag, Al, or a combination thereof). The diffusion preventing layer may be made of at least one selected from Ti, Ni, Cr, W and TiW, and Al and Ag may be used when high reflectance is required. When Au is used as the etch stop layer, not only the bonding strength with the additional reflective layer 95 is weak, but a part of Au may be damaged or damaged at the time of etching. Therefore, if the etching prevention layer is made of a material such as Ni, W, TiW, Cr, Pd, or Mo instead of Au, bonding strength with the additional reflective film 95 can be maintained and reliability can be improved.

The plurality of openings 64 and 65 are formed such that the first upper electrode 75 and the second upper electrode 85 are electrically connected to the first connection electrodes 72 and 74 and the second connection electrodes 82 and 84, And the openings 64 and 65 formed in the additional reflective film 95 are formed so as not to overlap the openings 64 and 65 formed in the nonconductive reflective film 91. The first connection electrodes 72 and 74 and the second connection electrodes 82 and 84 connect the first lower electrode 71 and the second lower electrode 81 through the openings 64 and 65, respectively. An opening 65 communicating with the first connection electrode 72 and 74 below the first upper electrode 75 and an opening 65 communicating with the second connection electrode 82 and 84 below the second upper electrode 85 64 are separated without being mixed with each other (see Fig. 17).

Next, as shown in FIG. 17, a first upper electrode 75 and a second upper electrode 85 may be deposited on the additional reflective film 95 using a sputtering equipment, an E-beam device, or the like. The first upper electrode 75 and the second upper electrode 85 are arranged to face each other. Some of the light passing through the additional reflection film 95 is reflected by the first upper electrode 75 and the second upper electrode 85. The first upper electrode 75 and the second upper electrode 85 are connected to the first connection electrodes 72 and 74 and the second connection electrodes 82 and 84 through the openings 64 and 65 formed in the additional reflection film 95, 84, respectively.

The first upper electrode 75 and the second upper electrode 85 may be electrically connected to electrodes provided on the outside (package, COB, submount, etc.) by a method such as a stud bump, a conductive paste, or an eutectic bonding. It is important that the height difference between the first upper electrode 75 and the second upper electrode 85 does not become large in the case of eutectic bonding. According to the semiconductor light emitting device of this example, since the first upper electrode 75 and the second upper electrode 85 can be formed on the additional reflective film 95 by the same process, there is almost no difference in height between the two electrodes. Therefore, it has an advantage in the case of eutectic bonding. The uppermost portion of the first upper electrode 75 and the uppermost portion of the second upper electrode 85 may be formed of Au / Sn alloy, Au / Sn / Cu alloy, etc., And may be formed of a tick bonding material.

In another embodiment, the first upper electrode 75 and the second upper electrode 85 may be electrically connected to the outside by soldering. In this case, the first upper electrode 75 and the second upper electrode 85 may have a reflective layer / diffusion prevention layer / solder layer sequentially stacked. For example, the reflective layer is made of Ag, Al or the like, and a contact layer (for example, Ti, Cr) may be added below the reflective layer. The diffusion preventing layer may be made of at least one selected from the group consisting of Ni, Ti, Cr, W and TiW. The soldering layer may be made of Au, or may be made of Sn (soldering layer) / Au (antioxidant layer), or Sn containing only Au, or heat treated Sn. Lead free solder may be used as the solder.

Various embodiments of the present disclosure will be described below.

(1) A semiconductor light emitting device comprising: a first semiconductor layer having a first conductivity; a second semiconductor layer having a second conductivity different from the first conductivity; and a second semiconductor layer interposed between the first and second semiconductor layers, A plurality of semiconductor layers having active layers for generating light through recombination of the semiconductor layers; A first electrode portion that is in electrical communication with the first semiconductor layer and supplies one of electrons and holes; A second electrode portion that is in electrical communication with the second semiconductor layer and supplies the remaining one of electrons and holes; A non-conductive reflective film formed on the plurality of semiconductor layers so as to reflect light generated in the active layer toward the first semiconductor layer, the non-conductive reflective film having an opening formed therein; And an additional reflective film formed on the non-conductive reflective film so as to reflect the light transmitted through the non-conductive reflective film toward the first semiconductor layer, wherein at least one of the first and second electrode parts comprises: A lower electrode electrically connected to the plurality of semiconductor layers; And a connection electrode formed between the non-conductive reflective film and the additional reflective film and electrically connected to the lower electrode through the opening.

(2) The non-conductive reflective film includes a first distributed Bragg reflector (DBR).

(3) The semiconductor light emitting device according to any one of (1) to (3), further comprising a second distributed Bragg reflector (DBR).

(4) The semiconductor light emitting device according to (4), wherein the further reflective film is a metal reflective film.

(5) The additional reflective film may include: a lower dielectric film between the second distributed Bragg reflector and the non-conductive reflective film; And an upper dielectric film on the second distributed Bragg reflector; Wherein the semiconductor light emitting device comprises at least one of a light emitting diode and a light emitting diode.

(6) At least one of the first electrode portion and the second electrode portion (the electrode having the lower electrode and the connection electrode) is formed on the additional reflection film and electrically connected to the connection electrode through the opening formed in the additional reflection film And an upper electrode formed on the semiconductor layer.

(7) A semiconductor light emitting device, comprising: a plurality of openings formed in a non-conductive reflective film; and connection electrodes connecting a plurality of openings.

(8) The semiconductor light emitting device according to (8), wherein the lower electrode is distributed over a plurality of semiconductor layers in a plurality of island shapes.

(9) The connection electrode comprises: a contact layer which is in contact with the lower electrode through an opening formed in the nonconductive reflective film; And an etch stop layer formed on the contact layer and having a portion corresponding to the opening formed in the additional reflective film removed.

(10) The non-conductive reflective film includes: a dielectric film between a plurality of semiconductor layers and a first distributed Bragg reflector; And a clad film between the first distributed Bragg reflector and the additional reflective film; Wherein the semiconductor light emitting device comprises at least one of a light emitting diode and a light emitting diode.

(11) the lower electrode comprises: a contact layer in electrical communication with a plurality of semiconductor layers; A reflective layer formed on the contact layer; A diffusion barrier layer formed on the reflective layer; An anti-oxidation layer formed on the diffusion preventing layer; And an anti-etching layer formed on the anti-oxidation layer and having a portion corresponding to the opening removed, wherein the connection electrode contacts the anti-oxidation layer.

(12) the first electrode portion and the second electrode portion each include a lower electrode, a connecting electrode, and an upper electrode, the lower electrode of the first electrode portion is formed on the exposed first semiconductor layer, And a second opening is formed in the non-conductive reflective film, the connection electrode of the first electrode portion is connected to the lower electrode of the first electrode portion by being led to the first opening, And the upper electrode of the first electrode part and the upper electrode of the second electrode part are provided opposite to each other on the additional reflective film, and the additional plurality of openings formed in the additional reflective film are connected to the lower electrode of the second electrode part, And a first distributed Bragg reflector that is connected to the connection electrode of the first electrode unit and the connection electrode of the second electrode unit via the first and second electrode units, respectively, and the non-conductive reflective film covers the lower electrodes of the first electrode unit and the second electrode unit, And a second distributed Bragg reflector covering the connection electrodes of the first electrode part and the second electrode part.

(13) a plurality of first openings and a plurality of second openings are formed in the non-conductive reflective film, the connection electrodes of the first electrode portion connect the plurality of first openings on the non-conductive reflective film, Wherein at least one of the connection electrode of the first electrode unit and the connection electrode of the second electrode unit is formed in a closed loop shape on the nonconductive reflective film.

According to one semiconductor light emitting device according to the present disclosure, the brightness is improved by reducing the light absorption loss by using a non-conductive reflective film instead of the metal reflective film.

Further, since the current diffusion into the plurality of semiconductor layers can be facilitated by the connection electrode-lower electrode structure through the plurality of openings uniformly formed in the non-conductive reflective film, the current can be diffused to the first semiconductor layer and / It is not necessary to form the metal strips as long as the electrodes, or it is sufficient to form a small number of water. As a result, the light absorption loss due to the metal is further reduced.

Further, even the light transmitted through the non-conductive reflective film is reflected by the additional reflective film, thereby improving the brightness.

Also, when the first connection electrode and the second connection electrode directly contact the first semiconductor layer or the current diffusion conductive film through the opening, the electrical contact may not be good. The first and second lower electrodes are connected to the connection electrode (For example, reduced contact resistance) between the first semiconductor layer and the current diffusion conductive film.

Further, when the opening is formed in the non-conductive reflective film or when the opening is formed in the additional reflective film, the top surface of the lower electrode or the top surface of the connection electrode is affected, thereby preventing the electrical contact from being deteriorated.

Further, the connection electrode connects the plurality of openings in the form of a closed loop to more evenly supply the current, thereby preventing deterioration due to current bias.

30: first semiconductor layer 40: active layer 50: second semiconductor layer
60: current diffusion conductive film 41: light absorption preventing film
62, 63: non-conductive reflective film side openings 64, 65:
71, 81: lower electrode 72, 74: first connecting electrode
82, 84: second connection electrode 91: non-conductive reflective film 95: additional reflective film
75: first upper electrode 85: second lower electrode

Claims (13)

In the semiconductor light emitting device,
A first semiconductor layer having a first conductivity, a second semiconductor layer having a second conductivity different from the first conductivity, and an active layer disposed between the first and second semiconductor layers and generating light through recombination of electrons and holes, A plurality of semiconductor layers;
A first electrode portion that is in electrical communication with the first semiconductor layer and supplies one of electrons and holes;
A second electrode portion that is in electrical communication with the second semiconductor layer and supplies the remaining one of electrons and holes;
A non-conductive reflective film formed on the plurality of semiconductor layers so as to reflect light generated in the active layer toward the first semiconductor layer, the non-conductive reflective film having an opening formed therein; And
And a further reflective film formed on the non-conductive reflective film so as to reflect the light transmitted through the non-conductive reflective film toward the first semiconductor layer,
At least one of the first electrode portion and the second electrode portion includes:
A lower electrode that is at least partially exposed by the opening and is electrically connected to the plurality of semiconductor layers; And
And a connection electrode formed between the non-conductive reflective film and the additional reflective film and electrically connected to the lower electrode through the opening. The method according to claim 1,
Wherein the non-conductive reflective film comprises a first distributed Bragg reflector (DBR). The method according to claim 1,
And the additional reflective film comprises a second distributed Bragg reflector (DBR). The method according to claim 1,
Wherein the additional reflective film is a metal reflective film. The method of claim 3,
Additional reflective films include:
A lower dielectric film between the second distributed Bragg reflector and the non-conductive reflective film; And
An upper dielectric film on the second distributed Bragg reflector; Wherein the semiconductor light emitting device comprises at least one of a light emitting diode and a light emitting diode. The method according to claim 1,
At least one of the first electrode portion and the second electrode portion (the electrode including the lower electrode and the connection electrode)
And an upper electrode formed on the additional reflective film and electrically connected to the connection electrode through an opening formed in the additional reflective film. The method according to claim 1,
Wherein a plurality of openings are formed in the non-conductive reflective film, and the connection electrode connects the plurality of openings. The method of claim 7,
Wherein the lower electrode is distributed over the plurality of semiconductor layers in the form of a plurality of islands. The method of claim 6,
The connecting electrodes are:
A contact layer contacting the lower electrode through an opening formed in the non-conductive reflective film; And
And an etch stop layer formed on the contact layer and having a portion corresponding to the opening formed in the additional reflective film removed. The method of claim 2,
The non-conductive reflective film is:
A dielectric film between the plurality of semiconductor layers and the first distributed Bragg reflector; And
A clad film between the first distributed Bragg reflector and the additional reflective film; Wherein the semiconductor light emitting device comprises at least one of a light emitting diode and a light emitting diode. The method according to claim 1,
The lower electrode comprises:
A contact layer in electrical communication with the plurality of semiconductor layers;
A reflective layer formed on the contact layer;
A diffusion barrier layer formed on the reflective layer;
An anti-oxidation layer formed on the diffusion preventing layer; And
An anti-oxidation layer formed on the anti-oxidation layer and having a portion corresponding to the opening removed,
And the connection electrode is in contact with the oxidation preventing layer. The method according to claim 1,
The first electrode portion and the second electrode portion each include a lower electrode, a connection electrode, and an upper electrode,
The lower electrode of the first electrode part is formed on the exposed first semiconductor layer, the second lower electrode is formed on the second semiconductor layer,
A first opening and a second opening are formed in the non-conductive reflective film,
The connection electrode of the first electrode part is connected to the lower electrode of the first electrode part connected to the first opening, the connection electrode of the second electrode part is connected to the lower electrode of the second electrode part,
The upper electrode of the first electrode part and the upper electrode of the second electrode part are provided to face each other on the additional reflection film and are connected to the connection electrode of the first electrode part and the connection electrode of the second electrode part, Lt; / RTI >
The non-conductive reflective film includes a first distributed Bragg reflector covering the lower electrodes of the first electrode unit and the second electrode unit. The additional reflective film includes a second distributed Bragg reflector covering the connection electrodes of the first electrode unit and the second electrode unit. The semiconductor light emitting device comprising: The method of claim 12,
A plurality of first openings and a plurality of second openings are formed in the nonconductive reflective film, the connection electrodes of the first electrode portion connect the plurality of first openings on the nonconductive reflective film, and the connection electrodes of the second electrode portion are formed on the non- Connecting the plurality of second openings,
Wherein at least one of the connection electrode of the first electrode unit and the connection electrode of the second electrode unit is formed in a closed loop shape on the non-conductive reflective film.

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