KR20220154641A - Light emitting device - Google Patents

Abstract

A light emitting device is disclosed. The light emitting device comprises: a light emitting structure; a first contact electrode and a second contact electrode positioned on the light emitting structure and making ohmic contact with the first and second conductivity type semiconductor layers, respectively; an insulating layer positioned on the light emitting structure and insulating the first contact electrode and the second contact electrode; a first bulk electrode and a second bulk electrode disposed on the light emitting structure and electrically connected to the first and second contact electrodes, respectively; an insulating support including first and second openings covering side surfaces and partial upper surfaces of the first and second bulk electrodes and partially exposing upper surfaces of the first and second bulk electrodes; and a first pad electrode and a second pad electrode at least partially filling the first and second openings, respectively. Areas of upper surfaces of the first and second bulk electrodes exposed by the first and second openings are smaller than horizontal sectional areas of the first and second bulk electrodes, respectively. The heat can be effectively emitted.

Description

Light emitting device {LIGHT EMITTING DEVICE}

The present invention relates to a light emitting device, and more particularly, to a light emitting device with improved heat dissipation efficiency and improved mechanical stability.

Recently, as the demand for small high-power light emitting devices increases, the demand for large-area flip-chip type light emitting devices with excellent heat dissipation efficiency is increasing. Electrodes of the flip chip type light emitting device are directly bonded to the secondary substrate, and since a wire for supplying external power to the flip chip type light emitting device is not used, heat dissipation efficiency is very high compared to a horizontal type light emitting device. Therefore, even if a high-density current is applied, heat can be effectively conducted toward the secondary substrate, and thus the flip chip type light emitting device is suitable as a high-power light emitting source.

In addition, for miniaturization and high output of the light emitting device, there is an increasing demand for a chip scale package using the light emitting device itself as a package, omitting a process of packaging the light emitting device in a separate housing. In particular, since the electrode of the flip chip type light emitting device can perform a similar function to the lead of the package, the flip chip type light emitting device can be usefully applied even in such a chip scale package.

When such a chip-scale package type device is used as a high-power light emitting device, a high-density current is applied to the chip-scale package. When a high-density current is applied, heat generated from the light emitting chip increases correspondingly, and accordingly, the heat dissipation efficiency of the high power light emitting device becomes a major factor in determining the reliability of the light emitting device. Accordingly, a highly reliable high-power chip-scale package having high heat dissipation efficiency and excellent mechanical stability is required.

An object to be solved by the present invention is to provide a light emitting device capable of effectively dissipating heat and having a mechanically stable structure.

A light emitting device according to an aspect of the present invention includes a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer positioned between the first and second conductivity type semiconductor layers; first contact electrodes and second contact electrodes disposed on the light emitting structure and making ohmic contacts to the first and second conductivity type semiconductor layers, respectively; an insulating layer disposed on the light emitting structure and insulating the first contact electrode and the second contact electrode; a first bulk electrode and a second bulk electrode disposed on the light emitting structure and electrically connected to the first and second contact electrodes, respectively; an insulating support including first and second openings covering side surfaces and partial upper surfaces of the first and second bulk electrodes and partially exposing upper surfaces of the first and second bulk electrodes; and a first pad electrode and a second pad electrode that at least partially fill the first and second openings, respectively, of upper surfaces of the first and second bulk electrodes exposed by the first and second openings. The area is smaller than the horizontal cross-sectional area of each of the first and second bulk electrodes.

Accordingly, a light emitting device having improved mechanical stability and heat dissipation characteristics may be provided.

A separation distance between the first and second bulk electrodes may be smaller than a separation distance between the first and second openings.

Furthermore, the separation distance between the first and second bulk electrodes may be 100 μm or less.

In addition, the separation distance between the first and second openings may be 80 μm or more.

The insulating support may include a lower insulating support covering side surfaces of the first and second bulk electrodes, and an upper insulating support covering portions of upper surfaces of the first and second bulk electrodes, the lower and upper insulating supports They may be formed of the same material as each other, or may be formed of different materials.

In addition, the upper insulating support may cover an interface between the first bulk electrode and the lower insulating support and an interface between the second bulk electrode and the lower insulating support.

The lower and upper insulating supports may be formed of different materials, and the upper insulating support may include photoresist or photosolder resist.

The upper surface of the first pad electrode, the upper surface of the second pad electrode, and the upper surface of the insulating support may be positioned side by side at the same height as each other.

The insulating layer may include a first insulating layer and a second insulating layer, the first insulating layer may partially cover the second contact electrode, and the first contact electrode may partially cover the first insulating layer. The second insulating layer may include a third opening and a fourth opening partially covering the first contact electrode to partially expose the first contact electrode and the second contact electrode.

The first bulk electrode may be electrically connected to the first contact electrode through the third opening, and the second bulk electrode may be electrically connected to the second contact electrode through the fourth opening.

The light emitting device may further include a connection electrode positioned between the second contact electrode and the second bulk electrode.

An upper surface of the connection electrode may be formed of the same material as that of the first contact electrode.

Also, a top surface of the connection electrode may be positioned at the same height as a top surface of the first contact electrode.

The light emitting structure may include one or more holes partially exposing the first conductivity type semiconductor layer, and the first contact electrode may be electrically connected to the first conductivity type semiconductor layer through the one or more holes. .

A light emitting device according to another aspect of the present invention includes a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer positioned between the first and second conductivity type semiconductor layers; first contact electrodes and second contact electrodes disposed on the light emitting structure and making ohmic contacts to the first and second conductivity type semiconductor layers, respectively; an insulating layer disposed on the light emitting structure and insulating the first contact electrode and the second contact electrode; a first bulk electrode and a second bulk electrode disposed on the light emitting structure and electrically connected to the first and second contact electrodes, respectively; and an insulating support including first and second openings covering side surfaces and partial upper surfaces of the first and second bulk electrodes and partially exposing upper surfaces of the first and second bulk electrodes. And, the separation distance between the first and second openings may be greater than the separation distance between the first and second bulk electrodes.

The second conductivity-type semiconductor layer may be a p-type semiconductor layer, and an area of an upper surface of the second bulk electrode exposed by the second opening is equal to a portion where the second bulk electrode and the second contact electrode contact each other. area can be greater than

In addition, the first conductivity-type semiconductor layer may be an n-type semiconductor layer, and an area of an upper surface of the first bulk electrode exposed by the first opening is a portion where the first bulk electrode and the first contact electrode are in contact. may be smaller than the area of

A horizontal cross-sectional area of the first bulk electrode may be greater than a horizontal cross-sectional area of the second bulk electrode.

A light emitting device according to another aspect of the present invention includes a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer positioned between the first and second conductivity type semiconductor layers; first contact electrodes and second contact electrodes disposed on the light emitting structure and making ohmic contacts to the first and second conductivity type semiconductor layers, respectively; an insulating layer disposed on the light emitting structure and insulating the first contact electrode and the second contact electrode; a first bulk electrode and a second bulk electrode disposed on the light emitting structure and electrically connected to the first and second contact electrodes, respectively; and an insulating support including first and second openings covering side surfaces and partial upper surfaces of the first and second bulk electrodes and partially exposing upper surfaces of the first and second bulk electrodes. And, the insulating support is located between the first and second bulk electrodes and on a portion of the upper surface of the first and second bulk electrodes on the upper part of the side surface on which the first and second bulk electrodes face each other.

The insulating support may be positioned on outer lateral surfaces of the first and second bulk electrodes and on portions of upper surfaces of the first and second bulk electrodes above the outer lateral surfaces of the first and second bulk electrodes.

According to embodiments of the present invention, it is possible to provide a light emitting device including an upper insulating support and a lower insulating support, including an insulating support covering side surfaces and some upper surfaces of the bulk electrodes. Accordingly, a highly reliable light emitting device having high heat dissipation efficiency, excellent mechanical stability, and low contamination by external factors such as moisture can be provided.

1 and 2 are cross-sectional and plan views for explaining a light emitting device according to an embodiment of the present invention.
3 is a cross-sectional view for explaining a light emitting device according to another embodiment of the present invention.
4 and 5 are cross-sectional and plan views for explaining a light emitting device according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments introduced below are provided as examples to sufficiently convey the spirit of the present invention to those skilled in the art. Accordingly, the present invention may be embodied in other forms without being limited to the embodiments described below. And, in the drawings, the width, length, thickness, etc. of components may be exaggerated for convenience. Also, when an element is described as being “on top of” or “on” another element, each part is “immediately on” or “directly on” the other element, as well as each element and other elements. It also includes the case where another component is interposed in between. Like reference numbers indicate like elements throughout the specification.

1 and 2 are cross-sectional and plan views for explaining a light emitting device according to an embodiment of the present invention. FIG. 1 shows a cross section of a region corresponding to the line II' of FIG. 2 .

1 and 2, the light emitting device 100 includes a light emitting structure 120, a first contact electrode 130, a second contact electrode 140, insulating layers 150 and 160, first and second It includes bulk electrodes 171 and 173 and an insulating support 180 . Furthermore, the light emitting device 100 may further include a growth substrate (not shown), a wavelength converter (not shown), and a connection electrode 145 .

The light emitting structure 120 includes a first conductivity type semiconductor layer 121, an active layer 123 positioned on the first conductivity type semiconductor layer 121, and a second conductivity type semiconductor layer (positioned on the active layer 123). 125) may be included. The first conductivity-type semiconductor layer 121, the active layer 123, and the second conductivity-type semiconductor layer 125 may include a IIIV-based compound semiconductor, for example, a nitride such as (Al, Ga, In)N. based semiconductors may be included. The first conductivity-type semiconductor layer 121 may include an n-type impurity (eg, Si), and the second conductivity-type semiconductor layer 125 may include a p-type impurity (eg, Mg). have. Also, the opposite may be true. The active layer 123 may include a multi-quantum well structure (MQW).

The light emitting structure 120 may include a region where the first conductivity type semiconductor layer 121 is partially exposed by partially removing the second conductivity type semiconductor layer 125 and the active layer 123 . For example, as shown, the light emitting structure 120 has at least one hole 120a exposing the first conductivity type semiconductor layer 121 through the second conductivity type semiconductor layer 125 and the active layer 123. ) may be included. In addition, the hole 120a may be formed in plurality, and the shape and arrangement of the hole 120a are not limited to those shown. In addition, in the region where the first conductivity type semiconductor layer 121 is partially exposed, the second conductivity type semiconductor layer 125 and the active layer 123 are partially removed to form the second conductivity type semiconductor layer 125 and the active layer ( 123) may be provided by forming a mesa.

In addition, the light emitting structure 120 may further include roughness R formed by increasing the roughness of the lower surface thereof. The roughness (R) may be formed using at least one of wet etching, dry etching, and electrochemical etching, and for example, PEC etching or an etching method using an etching solution containing KOH and NaOH. Thus, roughness (R) may be formed. As the roughness R is formed, protrusions and/or concavities in the ㎛ to nm scale formed on the surface of the first conductivity-type semiconductor layer 121 may be included. By forming roughness on the surface of the light emitting structure 120, the extraction efficiency of the light emitting device can be improved.

In addition, the light emitting structure 120 may further include a growth substrate (not shown) positioned under the first conductivity type semiconductor layer 121 . The growth substrate is not limited as long as it can grow the light emitting structure 120 thereon. For example, the growth substrate may be a sapphire substrate, a silicon carbide substrate, a silicon substrate, a gallium nitride substrate, an aluminum nitride substrate, or the like. Such a growth substrate may be separated from the light emitting structure 120 and removed using a known technique.

The second contact electrode 140 is positioned on the second conductivity type semiconductor layer 125 and may make ohmic contact with the second conductivity type semiconductor layer 125 . In addition, the second contact electrode 140 may at least partially cover the top surface of the second conductivity type semiconductor layer 125, and may be disposed to entirely cover the top surface of the second conductivity type semiconductor layer 125. have. In addition, the light emitting structure 120 may be formed as a single body to cover the top surface of the second conductivity type semiconductor layer 125 in areas other than the position where the hole 120a is formed. Accordingly, current is uniformly supplied to the entire light emitting structure 120, and current dissipation efficiency may be improved. However, the present invention is not limited thereto.

The second contact electrode 140 may include a material capable of making ohmic contact with the second conductivity-type semiconductor layer 125, and may include, for example, a metal material and/or a conductive oxide.

When the second contact electrode 140 includes a metal material, the second contact electrode 140 may include a reflective layer and a cover layer covering the reflective layer. As described above, the second contact electrode 140 can function to reflect light as well as being in ohmic contact with the second conductivity type semiconductor layer 125 . Accordingly, the reflective layer may include a metal capable of forming an ohmic contact with the second conductivity type semiconductor layer 125 while having high reflectivity. For example, the reflective layer may include at least one of Ni, Pt, Pd, Rh, W, Ti, Al, Mg, Ag, and Au. Also, the reflective layer may include a single layer or multiple layers.

The cover layer may prevent mutual diffusion between the reflective layer and another material, and prevent damage to the reflective layer due to diffusion of an external material into the reflective layer. Accordingly, the cover layer may be formed to cover the bottom and side surfaces of the reflective layer. The cover layer may be electrically connected to the second conductivity-type semiconductor layer 125 together with the reflective layer, so that it may serve as an electrode together with the reflective layer. The cover layer may include, for example, Au, Ni, Ti, Cr, or the like, and may include a single layer or multiple layers.

Meanwhile, when the second contact electrode 140 includes a conductive oxide, the conductive oxide may be ITO, ZnO, AZO, IZO, or the like. When the second contact electrode 140 includes a conductive oxide, it may cover a wider area of the top surface of the second conductive semiconductor layer 125 than when the second contact electrode 140 includes a metal. That is, the separation distance from the upper edge of the hole 120a to the second contact electrode 140 may be relatively shorter when the second contact electrode 140 is formed of a conductive oxide. In this case, the shortest distance from the contact point between the second contact electrode 140 and the second conductivity type semiconductor layer 125 to the contact point between the first contact electrode 130 and the first conductivity type semiconductor layer 121 Since can be relatively shorter, the forward voltage (V _f ) of the light emitting device 100 can be reduced.

In addition, when the second contact electrode 140 includes ITO, the first insulating layer 150 includes SiO ₂ , and the first contact electrode 130 includes Ag, the ITO/SiO 2 /Ag stack structure An omnidirectional reflector including may be formed.

The insulating layers 150 and 160 may include a first insulating layer 150 and a second insulating layer 160 . In addition, the insulating layers 150 and 160 may partially cover the first and second contact electrodes 130 and 140 . Hereinafter, the first insulating layer 150 will be described first, and contents related to the second insulating layer 160 will be described later.

The first insulating layer 150 may partially cover the upper surface of the light emitting structure 120 and the second contact electrode 140 . In addition, the first insulating layer 150 may cover the side surface of the hole 120a and partially expose the first conductive semiconductor layer 121 exposed to the hole 120a. The first insulating layer 150 may include an opening positioned at a portion corresponding to the hole 120a and an opening exposing a portion of the second contact electrode 140 . The first conductivity type semiconductor layer 121 and the second contact electrode 140 may be partially exposed through the openings.

The first insulating layer 150 may include an insulating material, for example, SiO ₂ , SiN _x , MgF ₂ and the like. Furthermore, the first insulating layer 150 may include multiple layers and may include a distributed Bragg reflector in which materials having different refractive indices are alternately stacked.

When the second contact electrode 140 includes a conductive oxide, the first insulating layer 150 may include a distributed Bragg reflector to improve light emitting efficiency of the light emitting device 100a. Also, unlike this, the second contact electrode 140 includes a conductive oxide, and the first insulating layer 150 is formed of a transparent insulating oxide (eg, SiO ₂ ), so that the second contact electrode 140, An omnidirectional reflector formed by a stacked structure of the first insulating layer 150 and the first contact electrode 130 may be formed.

Furthermore, unlike shown, the first insulating layer 150 may further cover at least a portion of the side surface of the light emitting structure 120 . The extent to which the first insulating layer 150 covers the side surface of the light emitting structure 120 may vary depending on whether chip unit isolation is performed during the manufacturing process of the light emitting device. That is, as in the present embodiment, the first insulating layer 150 may be formed to cover only the top surface of the light emitting structure 120. Alternatively, in the manufacturing process of the light emitting device 100, after the wafer is individualized into chip units, In the case of forming the first insulating layer 150 , even side surfaces of the light emitting structure 120 may be covered by the first insulating layer 150 .

The first contact electrode 130 may partially cover the light emitting structure 120, and through the hole 120a and the opening of the first insulating layer 150 positioned in a portion corresponding to the hole 120a, It may make ohmic contact with the conductive semiconductor layer 121 . The first contact electrode 130 may be formed to entirely cover other portions of the first insulating layer 150 except for a partial region. Also, the first contact electrode 130 may be electrically insulated from the second contact electrode 140 by the first insulating layer 150 .

Since the first contact electrode 130 is formed to entirely cover the upper surface of the light emitting structure 120 except for a partial area, current dissipation efficiency may be further improved. In addition, since the first contact electrode 130 may cover a portion not covered by the second contact electrode 140, the light emitting efficiency of the light emitting device 100 may be improved by more effectively reflecting light.

The first contact electrode 130 may make ohmic contact with the first conductivity-type semiconductor layer 121 and reflect light. Accordingly, the first contact electrode 130 may be formed of a single layer or multiple layers and may include a highly reflective metal layer such as an Al layer. The highly reflective metal layer may be formed on an adhesive layer of Ti, Cr, or Ni. However, the present invention is not limited thereto, and the first contact electrode 130 may include at least one of Ni, Pt, Pd, Rh, W, Ti, Al, Mg, Ag, and Au.

Also, unlike shown, the first contact electrode 130 may be formed to cover even the side surface of the light emitting structure 120 . When the first contact electrode 130 is also formed on the side surface of the light emitting structure 120, the light emitted from the side surface from the active layer 123 is reflected upward to increase the ratio of light emitted to the top surface of the light emitting device 100. can

Meanwhile, the light emitting device 100 may further include a connection electrode 145 .

The connection electrode 145 may be positioned on the second contact electrode 140 and may be electrically connected to the second contact electrode 140 through an opening of the first insulating layer 150 . Furthermore, the connection electrode 145 may electrically connect the second contact electrode 140 and the second bulk electrode 173 to each other. In addition, the connection electrode 145 may be formed to partially cover the first insulating layer 150 and may be spaced apart from and insulated from the first contact electrode 130 .

A top surface of the connection electrode 145 may be formed at substantially the same height as a top surface of the first contact electrode 130 . Also, the connection electrode 145 may be formed in the same process as the first contact electrode 130 . Accordingly, the connection electrode 145 and the first contact electrode 130 may include the same material. However, the present invention is not limited thereto, and the connection electrode 145 and the first contact electrode 130 may include different materials.

The second insulating layer 160 may partially cover the first contact electrode 130 and may partially expose the first contact electrode 130 through the first opening 160a and the second contact electrode 140 . A second opening 160b partially exposed may be included. One or more first and second openings 160a and 160b may be formed.

The second insulating layer 160 may include an insulating material, for example, SiO ₂ , SiN _x , and MgF ₂ . Furthermore, the second insulating layer 160 may include multiple layers and may include a distributed Bragg reflector in which materials having different refractive indices are alternately stacked.

The first bulk electrode 171 and the second bulk electrode 173 may be positioned on the light emitting structure 120, and each of the first bulk electrode 171 and the second bulk electrode 173 is a first contact electrode ( 130) and the second contact electrode 140. In particular, each of the first bulk electrode 171 and the second bulk electrode 173 may directly contact and be electrically connected to the first and second contact electrodes 130 and 140 . In this case, the first bulk electrode 171 and the second bulk electrode 173 may be electrically connected to the first and second contact electrodes 130 and 140 through the first and second openings 160a and 160b, respectively. .

The first bulk electrode 171 and the second bulk electrode 173 may have a thickness of several tens of μm or more, for example, about 70 μm to about 80 μm. When the bulk electrodes 171 and 173 have a thickness within the aforementioned range, the light emitting device itself can be used as a chip scale package.

The first bulk electrode 171 and the second bulk electrode 173 may be formed of a single layer or multiple layers, and may include an electrically conductive material. For example, each of the first bulk electrode 171 and the second bulk electrode 173 may include Cu, Pt, Au, Ti, Ni, Al, or Ag. Alternatively, it may include sintered metal particles and a non-metallic material interposed between the metal particles.

Meanwhile, the separation distance (Y) between the first bulk electrode 171 and the second bulk electrode 173 may be formed to be less than or equal to a predetermined value, and the light emitting device 100 may be mounted on a separate substrate. It may be the minimum number between the electrode pads exposed on the mounting surface of the light emitting element 100 required when doing this. Specifically, for example, when soldering is used to mount a predetermined light emitting element on a separate secondary substrate, the distance between electrode pads exposed on the mounting surface of the predetermined light emitting element is generally about 250 to prevent a short circuit. It is required to be more than μm. In addition, when eutectic bonding is used to mount a predetermined light emitting element on a separate secondary substrate, the distance between electrode pads exposed on the mounting surface of the predetermined light emitting element is generally about It is required to be 80 μm or more. According to the present embodiment, the separation distance Y between the first bulk electrode 171 and the second bulk electrode 173 may be less than or equal to this predetermined value, for example, less than or equal to about 250 μm, or less than or equal to about 100 μm. And, furthermore, it may be about 80 μm or less. By setting the separation distance (Y) between the first bulk electrode 171 and the second bulk electrode 173 to a predetermined value or less, the horizontal cross-sectional area and volume of the first bulk electrode 171 and the second bulk electrode 173 are relatively Since it can be made larger, heat generated when driving the light emitting device 100 can be effectively dissipated. In this regard, it will be described in additional detail below.

In addition, the first bulk electrode 171 and the second bulk electrode 173 may have different volumes, and the horizontal cross-sectional area of the first bulk electrode 171 is greater than the horizontal cross-sectional area of the second bulk electrode 173. can be big In this case, the first conductivity-type semiconductor layer 121 may be an n-type semiconductor layer, and the second conductivity-type semiconductor layer 125 may be a p-type semiconductor layer. In general, heat generated when the light emitting device 100 is driven is more concentrated on the first bulk electrode 171 serving as an n-type electrode compared to the second bulk electrode 173 serving as a p-type electrode. Accordingly, the heat dissipation efficiency of the light emitting device 100 may be improved by making the horizontal cross-sectional area of the first bulk electrode 171 larger than the horizontal cross-sectional area of the second bulk electrode 173 .

The insulating support 180 is positioned on the light emitting structure 120 and partially covers the side surfaces of the bulk electrodes 171 and 173 and the upper surfaces of the bulk electrodes 171 and 173 . In addition, the insulating support 180 may include a third opening 180a and a fourth opening 180b partially exposing upper surfaces of the first bulk electrode 171 and the second bulk electrode 173 .

The insulating support 180 may include a lower insulating support 181 and an upper insulating support 183, the lower insulating support 181 may surround the side surfaces of the bulk electrodes 171 and 173, and the upper insulation The support 183 may partially cover upper surfaces of the bulk electrodes 171 and 173 . In addition, the upper insulating support 183 may cover interfaces between the lower insulating support 181 and the bulk electrodes 171 and 173 .

The insulating support 180 has electrical insulation and covers side surfaces of the first bulk electrode 171 and the second bulk electrode 173 to effectively insulate them from each other. At the same time, the insulating support 180 may serve to support the first bulk electrode 171 and the second bulk electrode 173 .

The upper surfaces of the bulk electrodes 171 and 173 are partially covered by the upper insulating support 183, and the exposed areas 171a and 173a of the upper surfaces of the first and second electrodes 171 and 173 are respectively It may be smaller than the horizontal cross-sectional area of the first bulk electrode 171 and the horizontal cross-sectional area of the second bulk electrode 173 . In particular, the upper insulating support 183 may be positioned on the upper surfaces of the bulk electrodes 171 and 173 around the side surfaces where the first bulk electrode 171 and the second bulk electrode 173 face each other. Accordingly, the separation distance X between the exposed top surface 171a of the first bulk electrode 171 and the exposed top surface 173a of the second bulk electrode 173 is It is greater than the separation distance (Y) between (173).

Specifically in this regard, the light emitting element 100 is formed by forming a conductive material (eg, solder, conductive adhesive, eutectic material, etc.) between the exposed upper surfaces 171a and 173a and a separate substrate. ) and the separate substrate, the light emitting device 100 may be mounted on the separate substrate. In order to prevent an electric short from occurring between the bulk electrodes 171 and 173 due to the conductive material formed for bonding, the separation distance X between the exposed upper surfaces 171a and 173a is set to a predetermined value. It is required to be more than a numerical value. According to the present invention, the insulating support 180 is formed to partially cover the upper surfaces of the bulk electrodes 171 and 173, so that the exposed upper surface 171a of the first bulk electrode 171 and the second bulk electrode 173 The separation distance (X) between the exposed top surfaces 173a of ) may be formed to be greater than the separation distance (Y) between the first bulk electrode 171 and the second bulk electrode 173 . Therefore, while forming the separation distance (X) above a predetermined value capable of preventing an electrical short from occurring between the bulk electrodes 171 and 173, the separation distance between the bulk electrodes 171 and 173 (Y ) may be formed below a predetermined value capable of preventing an electrical short from occurring between the bulk electrodes 171 and 173. Accordingly, heat dissipation efficiency of the light emitting device 100 can be improved and electrical short circuits can be effectively prevented from occurring during the mounting process of the light emitting device 100 .

The separation distance (X) between the exposed upper surface 171a of the first bulk electrode 171 and the exposed upper surface 173a of the second bulk electrode 173 is not limited, but the light emitting element 100 is separated through soldering. When mounting on a substrate of the separation distance (X) may be about 250㎛ or more, further, when mounting the light emitting device 100 on a separate substrate through process bonding, the separation distance (X) is about 80㎛ or more can However, the present invention is not limited thereto.

In addition, the upper insulating support 183 is formed such that the separation distance X between the exposed upper surface 171a of the first bulk electrode 171 and the exposed upper surface 173a of the second bulk electrode 173 is greater than or equal to a predetermined value. It is sufficient if the bulk electrodes 171 and 173 are disposed in the upper peripheral region of the side surface facing each other, and the arrangement in other regions is not limited. For example, as shown in FIGS. 1 and 2 , the insulating support 180 positioned between the first and second bulk electrodes 171 and 173 may have a 'T' shape in cross section. Furthermore, the insulating support 180 covering the outer side surfaces of the first and second bulk electrodes 171 and 173 may have an 'A' shape in cross section.

In addition, the insulating support 180 and the bulk electrodes 171 and 173 may be formed of different materials. In particular, the insulating support 180 may include an insulating polymer and/or an insulating ceramic, and the bulk electrodes (171, 173) may include a metallic material. Accordingly, peeling or cracking may occur at the interface between the insulating support 180 and the bulk electrodes 171 and 173, and damage may occur due to stress and strain that may occur due to bonding of different materials. If the insulating support 180 and/or the bulk electrodes 171 and 173 are damaged, the light emitting structure 120 may be contaminated, and furthermore, cracks may occur in the light emitting structure 120, and thus the light emitting device 100 ) may be less reliable. According to the embodiments of the present invention, the insulating support 180 is formed to partially cover the side surfaces of the bulk electrodes 171 and 173 and the upper surfaces of the bulk electrodes 171 and 173, so that the insulating support 180 and Mechanical stability between the bulk electrodes 171 and 173 may be improved. Thus, the reliability of the light emitting device 100 can be improved.

In addition, since the mechanical stability of the light emitting device 100 is improved, it is possible to prevent the light emitting structure 120 from being damaged during the process of separating a growth substrate (not shown) from the light emitting structure 120 .

Furthermore, the lower insulating support 181 and the upper insulating support 183 may be formed of the same material or different materials.

When the lower insulating support 181 and the upper insulating support 183 are formed of the same material, the insulating support 180 may include, for example, a material such as EMC (Epoxy Molding Compound) or Si resin. . In addition, the insulating support 180 may include light reflective and light scattering particles such as TiO ₂ particles.

When the lower insulating support 181 and the upper insulating support 183 are formed of different materials, the upper insulating support 183 may be formed of a material having lower brittleness and/or lower hygroscopicity than the lower insulating support 181. can For example, the lower insulating support 181 may include a material such as EMC (Epoxy Molding Compound) or Si resin, and the upper insulating support 183 may include photoresist (PR) and/or photo solder resist (PSR). may contain substances such as

Since the upper insulating support 183 is formed of a material with relatively low brittleness, the probability of breaking or cracking is lower than that of the lower insulating support 181, so that there is a gap between the lower insulating support 181 and the bulk electrodes 171 and 173. Penetration of external contaminants through the interface can be prevented. In addition, since the upper insulating support 183 is formed of a material having relatively low hygroscopicity, penetration of external contaminants through the interface between the lower insulating support 181 and the bulk electrodes 171 and 173 can be prevented. For example, when the lower insulating support 181 is formed of a material with high hygroscopicity such as EMC, the light emitting device 100 can be more effectively protected from moisture by the upper insulating support 183 formed of a material such as PSR. have. In particular, when the upper insulating support 183 is formed to cover the interface between the lower insulating support 181 and the bulk electrodes 171 and 173, the above-described light emitting device 100 protection function can be exhibited more effectively.

Meanwhile, the area of the exposed top surface 171a of the first bulk electrode 171 may be smaller than the area of the area where the first bulk electrode 171 and the first contact electrode 130 come into contact, and the area of the second bulk electrode 173 The area of the exposed top surface 173a of ) may be larger than the area of the area where the second bulk electrode 173 and the second contact electrode 140 come into contact. In this case, the horizontal cross-sectional area of the first bulk electrode 171 may be greater than the horizontal cross-sectional area of the second bulk electrode 173 .

That is, by making the horizontal cross-sectional area of the first bulk electrode 171 larger than the horizontal cross-sectional area of the second bulk electrode 173, heat dissipation efficiency of the light emitting device 100 may be improved. At the same time, the area of the exposed upper surface 171a of the first bulk electrode 171 and the second bulk electrode 173 are larger than the ratio between the horizontal cross-sectional area of the first bulk electrode 171 and the horizontal cross-sectional area of the second bulk electrode 173. By further lowering the ratio between the areas of the exposed top surfaces 173a of , the areas of the exposed top surfaces 171a and 173a on the surface on which the light emitting device 100 is mounted may be substantially similar. Accordingly, the light emitting device 100 having more improved heat dissipation efficiency can be provided without changing a process of mounting the light emitting device 100 on a separate substrate.

In some embodiments, unlike shown, the insulating support 180 may cover up to the side of the light emitting structure 120 , and in this case, a light emitting angle of light emitted from the light emitting structure 120 may vary. For example, when the insulating support 180 further covers at least a portion of the side surface of the light emitting structure 120, some of the light emitted from the side surface of the light emitting structure 120 may be reflected to the lower surface of the light emitting structure 120. . In this way, by adjusting the region where the insulating support 180 is disposed, the light emitting angle of the light emitting device 100 can be adjusted.

On the other hand, the light emitting device 100 may further include a wavelength conversion unit (not shown), and light emitted from the light emitting structure 120 is wavelength-converted by the wavelength conversion unit to implement light of various colors. (100) may be provided. For example, when the wavelength conversion unit includes phosphors emitting red and green light and blue light is emitted from the light emitting structure 120, the light emitting device 100 may emit white light. Accordingly, a miniaturized high-output wafer-level white light emitting device can be provided.

The disposition position of the wavelength conversion unit is not limited, and may be formed, for example, on the lower surface of the light emitting structure 120 or further cover the side surface of the light emitting structure 120 .

3 is a cross-sectional view for explaining a light emitting device according to another embodiment of the present invention.

The light emitting device 200 of FIG. 3 is substantially similar to the light emitting device 100 described with reference to FIGS. 1 and 2, and is different in that it further includes a first pad electrode 191 and a second pad electrode 193. there is Hereinafter, the light emitting device 200 of the present embodiment will be described focusing on the differences, and detailed descriptions of the same components will be omitted.

1 and 2, the light emitting device 100 includes a light emitting structure 120, a first contact electrode 130, a second contact electrode 140, insulating layers 150 and 160, first and second It includes bulk electrodes 171 and 173, an insulating support 180, a first pad electrode 191 and a second pad electrode 193. Furthermore, the light emitting device 100 may further include a growth substrate (not shown), a wavelength converter (not shown), and a connection electrode 145 .

The first pad electrode 191 and the second pad electrode 193 may be positioned on the first bulk electrode 171 and the second bulk electrode 173, respectively, and also, the third of the insulating support 180, respectively. The opening 180a and the fourth opening 180b may be at least partially filled. Accordingly, the first pad electrode 191 and the second pad electrode 193 cover the exposed top surface 171a of the first bulk electrode 171 and the exposed top surface 173a of the second bulk electrode 173, respectively. can cover Accordingly, the distance between the first and second pad electrodes 191 and 193 is the distance between the exposed upper surface 171a of the first bulk electrode 171 and the exposed upper surface 173a of the second bulk electrode 173 (X ) can correspond to

In addition, as shown, upper surfaces of the first pad electrode 191 and the second pad electrode 193 may be flush with the upper surface of the insulating support 180 at substantially the same height. In this case, the upper surface of the light emitting device 100 may be formed substantially flat.

The first and second pad electrodes 191 and 193 may be formed using a method such as plating to fill the openings of the insulating support 180 . Thereafter, by partially removing the first and second pad electrodes 191 and 193 and the insulating support 180 using a physical and/or chemical method, for example, lapping or CMP, the first pad electrode ( 191) and the upper surface of the second pad electrode 193 may be formed parallel to the upper surface of the insulating support 180 at substantially the same height.

The first pad electrode 191 and the second pad electrode 193 may include a conductive material, in particular, a metallic material, such as Ni, Pt, Pd, Rh, W, Ti, Al, Au, or Sn. , Cu, Ag, Bi, In, Zn, Sb, Mg, Pb, and the like. The first and second pad electrodes 191 and 193 may include substantially the same material as the bulk electrodes 171 and 173 or may be formed of different materials. The first and second pad electrodes 191 and 193 may be formed using a deposition or plating method, and may be formed using, for example, electroless plating.

Since the light emitting element 200 further includes the first and second pad electrodes 191 and 193, the upper surface of the light emitting element 200 (which may be a surface on which the light emitting element 200 is mounted on a separate substrate) is substantially flat. can be formed. Accordingly, a process of mounting the light emitting device 200 on a separate substrate can be facilitated.

In addition, in the process of separating the growth substrate (not shown) from the light emitting structure 120 during the manufacturing process of the light emitting device 200, if a step exists on a surface opposite to the surface on which the growth substrate is located, light is emitted during separation of the growth substrate. The probability of occurrence of cracks or damage to the structure 120 increases. According to the present embodiment, the first and second pad electrodes 191 and 193 form a substantially flat surface opposite to the surface on which the growth substrate is located, so that the light emitting structure 120 in the process of separating the growth substrate damage can be prevented. Thus, the yield of the manufacturing process of the light emitting device 200 may be improved, and the reliability of the light emitting device 200 may be improved.

4 and 5 are cross-sectional and plan views for explaining a light emitting device according to another embodiment of the present invention.

The light emitting device 300 of this embodiment has a different structure of the light emitting structure 120 compared to the light emitting device 200 of FIGS. 1 and 2 . Accordingly, there is a difference in the mutual structural relationship of the other components, and the following will be described in detail focusing on the differences. Detailed descriptions of the same components are omitted.

Figure 4 (a) is a plan view of the light emitting device according to the present embodiment, (b) is a plan view for explaining the position of the hole (120h) and the position of the first opening (160a) and the second opening (160b). , FIG. 5 is a cross-sectional view showing a cross section of a region corresponding to lines IIII of FIG. 4 (a) and (b).

4 and 5 , the light emitting element 300 includes a light emitting structure 120, a first contact electrode 130, a second contact electrode 140, insulating layers 150 and 160, first and second It includes bulk electrodes 171 and 173 and an insulating support 180 . Furthermore, the light emitting device 300 may further include a growth substrate (not shown), a wavelength converter (not shown), a first pad electrode 191 and a second pad electrode 193 .

The light emitting structure 120 may include a region where the first conductivity type semiconductor layer 121 is partially exposed by partially removing the second conductivity type semiconductor layer 125 and the active layer 123 . For example, as shown, the light emitting structure 120 includes a plurality of holes 120h penetrating the second conductivity type semiconductor layer 125 and the active layer 123 to expose the first conductivity type semiconductor layer 121 . can include The holes 120h may be substantially regularly positioned throughout the light emitting structure 120 . However, the present invention is not limited thereto, and the arrangement shape and number of holes 120h may be variously modified.

In addition, the shape in which the first conductivity type semiconductor layer 121 is exposed is not limited to the same shape as the hole 120h. For example, the exposed region of the first conductivity-type semiconductor layer 121 may be formed in a line shape, a combination of a hole and a line, or the like.

The second contact electrode 140 may be positioned on the second conductivity type semiconductor layer 125 to make ohmic contact. The second contact electrode 140 may be disposed to entirely cover the top surface of the second conductivity type semiconductor layer 125, and furthermore, may be formed to almost completely cover the top surface of the second conductivity type semiconductor layer 125. have. The second contact electrode 140 may be formed as a single body throughout the light emitting structure 120. In this case, the second contact electrode 140 may include opening areas corresponding to positions of the plurality of holes 120h. can Accordingly, current is uniformly supplied to the entire light emitting structure 120, and current dissipation efficiency may be improved.

However, the present invention is not limited thereto, and the second contact electrode 140 may be formed of a plurality of unit units.

The first insulating layer 150 may partially cover the upper surface of the light emitting structure 120 and the second contact electrode 140 . The first insulating layer 150 may include an opening that covers side surfaces of the plurality of holes 120h and partially exposes the first conductive semiconductor layer 121 positioned on a lower surface of the hole 120h. Accordingly, the opening may be located corresponding to the position where the plurality of holes 120h are disposed. Also, the first insulating layer 150 may include an opening exposing a portion of the second contact electrode 140 . Furthermore, the first insulating layer 150 may further cover at least a portion of the side surface of the light emitting structure 120 .

The first contact electrode 130 may partially cover the light emitting structure 120 , and through holes 120h and openings of the first insulating layer 150 positioned in a portion corresponding to the holes 120h, the first contact electrode 130 may first It may make ohmic contact with the conductive semiconductor layer 121 . Also, unlike shown, the first contact electrode 130 may be formed to cover even the side surface of the light emitting structure 120 .

The second insulating layer 160 may partially cover the first contact electrode 130 and may partially expose the first contact electrode 130 through the first opening 160a and the second contact electrode 140 . A second opening 160b partially exposed may be included. One or more first and second openings 160a and 160b may be formed. In addition, the openings 160a and 160b may be located on opposite sides of each other.

The first bulk electrode 171 and the second bulk electrode 173 may be positioned on the light emitting structure 120, and each of the first bulk electrode 171 and the second bulk electrode 173 is a first contact electrode ( 130) and the second contact electrode 140.

Meanwhile, the separation distance Y between the first bulk electrode 171 and the second bulk electrode 173 may be formed to be less than a predetermined value, for example, about 250 μm or less, and further, about 80 μm or less. In addition, the first bulk electrode 171 and the second bulk electrode 173 may have different volumes, and the horizontal cross-sectional area of the first bulk electrode 171 is greater than the horizontal cross-sectional area of the second bulk electrode 173. can be big

The insulating support 180 is positioned on the light emitting structure 120 and partially covers the side surfaces of the bulk electrodes 171 and 173 and the upper surfaces of the bulk electrodes 171 and 173 . In addition, the insulating support 180 may include a third opening 180a and a fourth opening 180b partially exposing upper surfaces of the first bulk electrode 171 and the second bulk electrode 173 . The insulating support 180 may include a lower insulating support 181 and an upper insulating support 183, the lower insulating support 181 may surround the side surfaces of the bulk electrodes 171 and 173, and the upper insulation The support 183 may partially cover upper surfaces of the bulk electrodes 171 and 173 . In addition, the upper insulating support 183 may cover interfaces between the lower insulating support 181 and the bulk electrodes 171 and 173 .

The upper surfaces of the bulk electrodes 171 and 173 are partially covered by the upper insulating support 183, and the exposed areas 171a and 173a of the upper surfaces of the first and second electrodes 171 and 173 are respectively It may be smaller than the horizontal cross-sectional area of the first bulk electrode 171 and the horizontal cross-sectional area of the second bulk electrode 173 . In particular, the upper insulating support 183 may be positioned on the upper surfaces of the bulk electrodes 171 and 173 around the side surfaces where the first bulk electrode 171 and the second bulk electrode 173 face each other. Accordingly, the separation distance X between the exposed top surface 171a of the first bulk electrode 171 and the exposed top surface 173a of the second bulk electrode 173 is It is greater than the separation distance (Y) between (173).

The separation distance (X) between the exposed upper surface 171a of the first bulk electrode 171 and the exposed upper surface 173a of the second bulk electrode 173 is not limited, but the light emitting element 100 is separated through soldering. When mounting on a substrate of the separation distance (X) may be about 250㎛ or more, further, when mounting the light emitting device 100 on a separate substrate through process bonding, the separation distance (X) is about 80㎛ or more can However, the present invention is not limited thereto.

Furthermore, the lower insulating support 181 and the upper insulating support 183 may be formed of the same material or different materials.

In particular, when the lower insulating support 181 and the upper insulating support 183 are formed of different materials, the upper insulating support 183 is made of a material having lower brittleness and/or lower hygroscopicity than the lower insulating support 181. can be formed For example, the lower insulating support 181 may include a material such as EMC (Epoxy Molding Compound) or Si resin, and the upper insulating support 183 may include photoresist (PR) and/or photo solder resist (PSR). may contain substances such as

Meanwhile, the area of the exposed top surface 171a of the first bulk electrode 171 may be smaller than the area of the area where the first bulk electrode 171 and the first contact electrode 130 come into contact, and the area of the second bulk electrode 173 The area of the exposed top surface 173a of ) may be larger than the area of the area where the second bulk electrode 173 and the second contact electrode 140 come into contact. In this case, the horizontal cross-sectional area of the first bulk electrode 171 may be greater than the horizontal cross-sectional area of the second bulk electrode 173 .

The first pad electrode 191 and the second pad electrode 193 may be positioned on the first bulk electrode 171 and the second bulk electrode 173, respectively, and also, the third of the insulating support 180, respectively. The opening 180a and the fourth opening 180b may be at least partially filled. Accordingly, the first pad electrode 191 and the second pad electrode 193 cover the exposed top surface 171a of the first bulk electrode 171 and the exposed top surface 173a of the second bulk electrode 173, respectively. can cover Accordingly, the distance between the first and second pad electrodes 191 and 193 is the distance between the exposed top surface 171a of the first bulk electrode 171 and the exposed top surface 173a of the second bulk electrode 173 (Y ) can correspond to In addition, as shown, upper surfaces of the first pad electrode 191 and the second pad electrode 193 may be flush with the upper surface of the insulating support 180 at substantially the same height. In this case, the upper surface of the light emitting device 100 may be formed substantially flat.

In the above, various embodiments of the present invention have been described, but the present invention is not limited to the above-described respective embodiments and features. Inventions changed through combination and substitution of technical features described in the embodiments are also included in the scope of the present invention, and various modifications and changes are possible without departing from the technical spirit of the claims of the present invention.

Claims (6)

a light emitting structure including a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer positioned between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer;
a first contact electrode and a second contact electrode disposed on the light emitting structure and making ohmic contact with the first conductivity type semiconductor layer and the second conductivity type semiconductor layer, respectively;
an insulating layer disposed on the light emitting structure and insulating the first contact electrode and the second contact electrode;
a first bulk electrode and a second bulk electrode disposed on the light emitting structure and electrically connected to the first contact electrode and the second contact electrode, respectively;
a first electrode and a second electrode electrically connected to the first bulk electrode and the second bulk electrode, respectively;
a first insulating support covering side surfaces of the first bulk electrode and the second bulk electrode; and
Including; a second insulating support in contact with the side surfaces of the first electrode and the second electrode,
The first insulating support and the second insulating support are formed of different materials,
The width of the second insulating support between the first electrode and the second electrode is wider than the width between the first bulk electrode and the second bulk electrode,
The first bulk electrode and the second bulk electrode and the first electrode and the second electrode are formed of the same material, and the outer surface of the first insulating support and the outer surface of the second insulating support are located side by side light emitting element.
The method of claim 1,
The second insulating support is a light emitting element covering an interface between the first bulk electrode and the first insulating support and an interface between the second bulk electrode and the first insulating support.
The method of claim 1,
The first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer include a III-V series compound semiconductor,
The first conductivity-type semiconductor layer includes an n-type impurity,
The second conductivity-type semiconductor layer includes a p-type impurity.
The method of claim 1,
The first bulk electrode and the second bulk electrode each include at least one of Cu, Pt, Au, Ti, Ni, Al, and Ag.
The method of claim 1,
The horizontal cross-sectional area of the first bulk electrode is formed to be larger than the horizontal cross-sectional area of the second bulk electrode.
The method of claim 1,
The first insulating support is a light emitting device comprising at least one of EMC (Epoxy Molding Compound) and Si resin.

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