KR102075059B1 - Light emitting device and light emitting device package - Google Patents

Abstract

The light emitting device includes a light emitting structure that generates light and at least one electrode structure disposed on the light emitting structure. The at least one electrode structure is disposed on the light emitting structure and includes a current blocking layer comprising a plurality of blocking patterns, a current spreading layer disposed on the current blocking layer and comprising a plurality of diffusion patterns, and a current spreading layer disposed on the current spreading layer. And an electrode layer 46 formed on the light emitting structure through the current blocking layer.

Description

Light emitting device and light emitting device package

An embodiment relates to a light emitting device.

Embodiments relate to a light emitting device package.

Research into light emitting device packages having light emitting devices is being actively conducted.

The light emitting device is, for example, a semiconductor light emitting device or a semiconductor light emitting diode which is formed of a semiconductor material and converts electrical energy into light.

Semiconductor light emitting devices have the advantages of low power consumption, semi-permanent life, fast response speed, safety and environmental friendliness compared to conventional light sources such as fluorescent and incandescent lamps. Therefore, a lot of researches are being conducted to replace the existing light source with a semiconductor light emitting device.

BACKGROUND OF THE INVENTION Semiconductor light emitting devices have been increasingly used as light sources for lighting devices such as various lamps, liquid crystal display devices, electronic signs, and street lamps that are used indoors and outdoors.

The embodiment provides a light emitting device capable of preventing concentration of current.

The embodiment provides a light emitting device capable of diffusing current.

The embodiment provides a light emitting device capable of improving the bonding force of the electrode.

The embodiment provides a light emitting device capable of improving light extraction efficiency.

According to an embodiment, the light emitting device comprises: a light emitting structure for generating light; And at least one electrode structure disposed on the light emitting structure, wherein the at least one electrode structure comprises: a current blocking layer disposed on the light emitting structure and including a plurality of blocking patterns; A current diffusion layer disposed on the current blocking layer and including a plurality of diffusion patterns; And an electrode layer disposed on the current spreading layer and formed on the light emitting structure through the current spreading layer and the current blocking layer.

According to an embodiment, the light emitting device package, the body; First and second lead electrodes disposed on the body; A light emitting element disposed on any one of the body and the first and second lead electrodes; And a molding member surrounding the light emitting element.

According to the embodiment, the current blocking layer may be disposed under the electrode layer 46 to prevent concentration of current, thereby improving luminous efficiency.

According to the embodiment, the current diffusion layer may be disposed under the electrode layer 46 to diffuse the current to improve the luminous efficiency.

According to the embodiment, the electrode layer 46 penetrates the current spreading layer and the current blocking layer to be in contact with the light emitting structure, thereby preventing the electrode layer 46 from being peeled off, thereby improving reliability of the device.

Embodiments may allow a current blocking layer including a plurality of layers having different refractive indices to have a reflective function, thereby improving light extraction efficiency due to reflection of light.

1 is a cross-sectional view showing a light emitting device according to the embodiment.
2 is a view showing an electrode structure according to the first embodiment.
3 illustrates an exemplary shape of the electrode structure of FIG. 2.
4 is another exemplary shape of the electrode structure of FIG.
5 is a view showing an electrode structure according to a second embodiment.
6 is a view showing an electrode structure according to a third embodiment.
7 illustrates an exemplary shape of the electrode structure of FIG. 6.
8 illustrates another exemplary shape of the electrode structure of FIG. 6.
9 is a view showing an electrode structure according to a fourth embodiment.
10 is a cross-sectional view showing a horizontal light emitting device according to the first embodiment.
11 is a cross-sectional view illustrating a flip type light emitting device according to a second embodiment.
12 is a cross-sectional view illustrating a light emitting device package according to an embodiment.

In the description of the embodiment according to the invention, in the case where it is described as being formed on the "top" or "bottom" of each component, the top (bottom) or the bottom (bottom) is the two components are mutually It includes both direct contact or one or more other components formed and formed between two components. In addition, when expressed as "up (up) or down (down)" may include the meaning of the down direction as well as the up direction based on one component.

1 is a cross-sectional view showing a light emitting device according to the embodiment.

Referring to FIG. 1, the light emitting device according to the embodiment may include a light emitting structure 20 and an electrode structure 40 formed on the light emitting structure 20.

The light emitting structure 20 may include a plurality of compound semiconductor layers. The plurality of compound semiconductor layers may include at least a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer, but are not limited thereto. The first conductive semiconductor layer may be an n-type semiconductor layer, and the second conductive semiconductor layer may be a p-type semiconductor layer, but is not limited thereto.

At least one electrode structure 40 may be formed in the light emitting structure 20 according to the type of the light emitting device.

As will be described later, the light emitting device may include one of a horizontal light emitting device (see FIG. 10) and a flip type light emitting device (see FIG. 11), but is not limited thereto.

The electrode structure 40 of the embodiment may be formed in the horizontal light emitting device and the flip light emitting device.

In the case of the horizontal light emitting device and / or the flip type light emitting device, the electrode structure 40 may include a first electrode structure and a second electrode structure. For example, the first electrode structure is formed on the first conductive semiconductor layer of the light emitting structure 20, and the second electrode structure is formed on the second conductive semiconductor layer of the light emitting structure 20. Can be. In this case, the second conductive semiconductor layer and the active layer may be removed from the light emitting structure 20 to expose the first conductive semiconductor layer.

Accordingly, power may be applied to the first and second electrode structures to generate light in the active layer of the light emitting structure 20.

The electrode structure 40 may include, but is not limited to, a current blocking layer (CBL), a current spreading layer (CPL), and an electrode layer 46. The electrode layer 46 may be formed in a single layer or a multilayer structure including at least one selected from the group consisting of V, W, Au, Ti, Ni, Pd, Ru, Cu, Al, Cr, Ag, and Pt.

The current blocking layer may serve to block current from being concentrated in the light emitting structure 20 vertically overlapping the electrode layer 46. To this end, the current blocking layer may be formed between the electrode layer 46 and the light emitting structure 20.

The current blocking layer may be in Schottky contact with the light emitting structure 20. Accordingly, the current is not smoothly supplied to the light emitting structure 20 which is in contact with the current blocking layer and the Schottky contact.

The current may be blocked by the current blocking layer so as not to flow completely, or may flow relatively smaller than the electrode layer 46 through the current blocking layer.

Since the current may be diffused by the current spreading layer, the current may flow completely to most regions of the light emitting structure except for the current blocking layer. Therefore, the current flows to the light emitting structure 20 near the electrode layer 46 relatively little or not completely, and the current flows to the light emitting structure 20 other than the electrode layer 46 to prevent concentration of the current. The luminous efficiency can be improved.

The current blocking layer may be formed of a material having a smaller electrical conductivity than the electrode layer 46, having a larger electrical insulation than the electrode layer 46, or forming a schottky contact with the light emitting structure 20. Can be.

The current blocking layer may be formed of a transparent and high resistance conductive material or a transparent insulating material. For example, the transparent and high resistance conductive material may include at least one selected from the group consisting of ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, and ZnO. The transparent insulating material may include at least one selected from the group consisting of SiO ₂ , SiO _x , SiO _x N _y , Si ₃ N ₄ , and Al ₂ O ₃ .

The electrode layer 46 may include a metal material that is opaque and excellent in electrical conductivity, but is not limited thereto. Examples of the metal material include aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), platinum (Pt), gold (Au), tungsten (W), copper (Cu), and molybdenum (Mo). It may include one or an alloy thereof selected from the group consisting of), but is not limited thereto.

The electrode structure 40 may include, but is not limited to, a bonding pad and a plurality of electrode lines electrically connected to the bonding pad.

Each of the bonding pads and the electrode lines may include a current blocking layer, a current spreading layer, and an electrode layer 46.

Alternatively, the bonding pad may include the current blocking layer, the current spreading layer, and the electrode layer 46, and the electrode line may include the current spreading layer and the electrode layer 46. In this case, the current spreading layer may include an opening corresponding to the electrode layer 46. The electrode layer 46 may be formed to be in contact with the top surface of the light emitting structure 20 through the opening and to be in contact with a portion of the top surface of the current diffusion layer around the opening of the current diffusion layer, but is not limited thereto. Do not.

The current spreading layer may be a conductive material having excellent transmittance (hereinafter referred to as a transparent conductive material) or a conductive material having excellent reflectance (hereinafter referred to as a reflective conductive material). Both the transparent conductive material and the reflective conductive material may have excellent electrical conductivity.

The reflective conductive material may be, for example, an opaque metal material, but is not limited thereto.

Examples of the transparent conductive material include ITO, IZO (In-ZnO), GZO (Ga-ZnO), AZO (Al-ZnO), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), IrOx, RuOx. At least one selected from the group consisting of RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO.

For example, at least one or two or more alloys selected from the group consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf may be used as the reflective conductive material. Do not.

In the horizontal light emitting device, the current spreading layer of the electrode structure 40 may be a transparent layer including a transparent conductive material, but is not limited thereto.

In the horizontal light emitting device, light generated in the active layer of the light emitting structure 20 may be emitted to the outside through the transparent conductive layer of the electrode structure 40.

In the flip light emitting device, the current spreading layer of the electrode structure 40 may be a reflective layer including a reflective conductive material, but is not limited thereto.

In the flip light emitting device, light generated in the active layer of the light emitting structure 20 may be reflected by the reflective layer and emitted to the outside through the first conductive semiconductor layer.

Hereinafter, the electrode structure 40 will be described in more detail.

2 is a view showing an electrode structure according to the first embodiment.

Referring to FIG. 2, the electrode structure 40 according to the first embodiment is formed on the current blocking layer 42, the light emitting structure 40, and the current blocking layer 42 formed on the light emitting structure 20. The formed current spreading layer 44 and at least the electrode layer 46 formed on the current spreading layer 44 may be included.

Since the current blocking layer 42, the current spreading layer 44, and the electrode layer 46 have been described above, a brief description thereof will be provided below.

The current spreading layer 44 may be formed on most regions of the upper surface of the light emitting structure 20. The current spreading layer 44 may supply the current provided from the electrode layer 46 to all regions of the light emitting structure 20. That is, the current of the electrode layer 46 may be diffused in the current diffusion layer 44. Therefore, since the current spreading layer 44 is formed in most of the region of the upper surface of the light emitting structure 20, the current supplied to the current spreading layer 44 is diffused to be supplied to the entire region of the light emitting structure 20. Can be.

The formation of the current spreading layer 44 is deeply related to the electrode layer 46 being partially or locally formed on the light emitting structure 20.

That is, the electrode layer 46 may be locally or partially formed on the top surface of the light emitting structure 20 instead of being formed on the entire area of the top surface of the light emitting structure 20. Therefore, since the electrode layer 46 does not come into contact with the entire area of the upper surface of the light emitting structure 20, current is not supplied from the electrode layer 46 to the entire area of the light emitting structure 20, and the electrode layer 46 is not provided. Intensive supply to the light emitting structure 20 corresponding to the vertical. Accordingly, almost no current is supplied to the light emitting structure 20 that does not correspond to the electrode layer 46 perpendicularly. Therefore, light is mainly generated in the active layer of the light emitting structure 20 that is perpendicular to the electrode layer 46, and light is not generated well in the active layer of the light emitting structure 20 that is not perpendicular to the electrode layer 46. The luminous efficiency can be lowered.

Therefore, in order to supply the current of the electrode layer 46 to the entire area of the light emitting structure 20, the current spreading layer 44 is formed on the entire area of the upper surface of the light emitting structure 46, the current spreading layer An electrode layer 46 may be locally or partially formed on the 44 and the current spreading layer 44.

The current blocking layer 42 may include a plurality of blocking patterns 43, and the current spreading layer 44 may include a plurality of diffusion patterns 45, but is not limited thereto.

The blocking blocking layer and the blocking pattern 43 may be formed to protrude toward the electrode layer 46 from an upper surface of the light emitting structure, but are not limited thereto.

The diffusion pattern 45 of the current spreading layer 44 has the same width as the blocking pattern 43 of the current blocking layer 42 or has a width larger than that of the blocking pattern 43 of the current blocking layer 42. However, this is not limitative.

The diffusion pattern 45 of the current diffusion layer 44 may be formed to surround the blocking pattern 43 of the current blocking layer 42, but is not limited thereto. That is, the diffusion pattern 45 of the current diffusion layer 44 may be formed on the side surface and the top surface of the blocking pattern 43 of the current blocking layer 42.

The side surface of the blocking pattern 43 of the current blocking layer 42 and / or the side surface of the diffusion pattern 45 of the current spreading layer 44 may be one of a vertical surface, an inclined surface, two surfaces, and an uneven surface with respect to the upper surface of the light emitting structure. It may have any one, but is not limited thereto.

The electrode layer 46, the diffusion pattern 45 of the current diffusion layer 44, and the blocking pattern 43 of the current blocking layer 42 may have a circular shape as shown in FIG. 3 or as shown in FIG. 4. It can have a square, but not limited thereto.

The electrode structure 40 of FIGS. 3 and 4 has a diffusion pattern 45 of the electrode layer 46, the current diffusion layer 44, and a blocking pattern 43 of the current blocking layer 42 when viewed from the light emitting structure. The back shape of is shown.

The width between the blocking pattern 43 of the current blocking layer 42 and the blocking pattern 43 of the current blocking layer 42 may be the same or different. The width of the blocking pattern 43 of the current blocking layer 42 may be smaller than an interval between the blocking patterns 43 of the current blocking layer 42, but is not limited thereto.

Similarly, the width between the diffusion pattern 45 of the current diffusion layer 44 and the diffusion pattern 45 of the current diffusion layer 44 may be the same or different. The width of the diffusion pattern 45 of the current spreading layer 44 may be smaller than the gap between the diffusion patterns 45 of the current spreading layer 44, but is not limited thereto.

The electrode layer 46 is formed on the upper surface of the light emitting structure exposed between the diffusion pattern 45 of the current diffusion layer 44 and the blocking pattern 43 of the current blocking layer 42 and the current diffusion layer 44. May be formed on an upper surface of the diffusion pattern 45.

The electrode layer 46 may contact at least two or more regions of the upper surface of the light emitting structure between the diffusion pattern 45 of the current diffusion layer 44 and the blocking pattern 43 of the current blocking layer 42. have.

In other words, the electrode layer 46 may pass through the current diffusion layer 44 and the current blocking layer 42 to be in contact with the top surface of the light emitting structure.

Since the electrode layer 46 contacts the top surface of the light emitting structure, the side surface of the blocking pattern 43, and the side surface and the top surface of the diffusion pattern 45, the junction area of the electrode layer 46 is maximized, thereby the electrode layer 46. Peel off can be prevented.

Although not shown, all of the diffusion patterns 45 of the current diffusion layer 44 may be removed. That is, since the plurality of current diffusion patterns 45 are removed, the current diffusion layer 44 may have an opening slightly smaller than the width of the electrode layer 46. A plurality of blocking patterns 43 and the light emitting structure of the current blocking layer 42 may be exposed through the opening of the current spreading layer 44.

As the electrode layer 46 is formed to cover the opening, the electrode layer 46 may be formed in contact with the top surface of the light emitting structure exposed by the opening and the top surface of the blocking pattern 43 of the electrode blocking layer.

The back surface of the electrode layer 46 may protrude from the top surface of the diffusion pattern 45 of the current diffusion layer 44 or the top surface of the blocking pattern 43 of the current blocking layer 42 toward the top surface of the light emitting structure. .

5 is a view showing an electrode structure according to a second embodiment.

The second embodiment is almost similar to the first embodiment except that a plurality of blocking patterns 43 of the current blocking layer 42 are formed in the foot and the structure. Therefore, in the second embodiment, the same reference numerals are assigned to components having the same shape or the same function as the first embodiment, and detailed description thereof will be omitted. Content not described in the second embodiment will be easily understood from the first embodiment.

Referring to FIG. 5, the electrode structure 40 according to the second embodiment includes a current blocking layer 42 formed on the light emitting structure, and a current diffusion layer 44 formed on the light emitting structure and the current blocking layer 42. And an electrode layer 46 formed on at least the current blocking layer 42.

Since the current blocking layer 42, the current spreading layer 44, and the electrode layer 46 have been described above, a brief description thereof will be provided below.

A plurality of grooves may be formed on the upper surface of the light emitting structure. The groove may be a groove having the upper surface of the foot and the structure removed to a certain depth from the upper surface.

Since the groove corresponds to the shape of the current blocking layer 42 shown in FIGS. 3 and 4, the groove may be circular or square when viewed from above, but is not limited thereto.

The inner surface of the groove may include any one of a vertical surface, an inclined surface, a round surface, and an uneven surface with respect to the upper surface of the light emitting structure, but is not limited thereto.

A plurality of blocking patterns 43 of the current blocking layer 42 may be formed in the plurality of grooves. The top surface of the blocking pattern 43 may completely fill the groove and coincide with the top surface of the light emitting structure, but is not limited thereto.

The third and fourth embodiments below are almost similar to the first and second embodiments except for the current blocking layer 42 having a reflecting function for reflecting light. Therefore, in the third and fourth embodiments, the same reference numerals are assigned to components having the same shape or the same function as the first and second embodiments, and detailed description thereof will be omitted. Content not described in the third and fourth embodiments will be readily understood from the first and second embodiments.

6 is a view showing an electrode structure according to a third embodiment.

Referring to FIG. 6, the electrode structure 40 according to the third embodiment includes a current blocking layer 42 formed on the light emitting structure, and a current diffusion layer 44 formed on the light emitting structure and the current blocking layer 42. And an electrode layer 46 formed on at least the current blocking layer 42.

The current blocking layer 42 may protrude from the upper surface of the light emitting structure toward the electrode layer 46.

The current blocking layer 42 may include a plurality of blocking patterns 43, but is not limited thereto.

The current blocking layer 42 or the blocking pattern 43 may have a structure in which a plurality of first dielectric layers 101 and a plurality of second dielectric layers 103 are alternately stacked.

The first and second dielectric layers 101 and 103 may include one of TiO ₂ , SiO ₂ , Nb ₂ O ₅ , ZrO ₂ , ZnO ₂ , Al ₂ O ₃ , Si ₃ N _4, and Si _x N _y . However, this is not limitative.

The current blocking layer 42 or the blocking pattern 43 may have a reflection function to reflect light by alternately stacking the first and second dielectric layers 101 and 103 having different refractive indices. Such a structure may be referred to as a distributed Bragg Refelctor (DBR) structure, but is not limited thereto.

The first dielectric layer 101 may have a high refractive index, and the second dielectric layer 103 may have a low refractive index. On the contrary, the first dielectric layer 101 may have a low refractive index and the second dielectric layer 103 may have a high refractive index.

Accordingly, the first dielectric layer 101 may have a relatively high refractive index compared to the second dielectric layer 103, or the second dielectric layer 103 may have a relatively high refractive index relative to the first dielectric layer 101. May have

The number of the first dielectric layer 101 and the second dielectric layer 103 may vary according to a desired reflectance. For example, the first dielectric layer 101 and the second dielectric layer 103 may have at least two cycles, but are not limited thereto. Here, one cycle may include a first dielectric layer and a second dielectric layer. Therefore, two cycles may include the first dielectric layer 101, the second dielectric layer 103, the first dielectric layer 101, and the second dielectric layer 103. The first dielectric layer 101 and the second dielectric layer 103 may be referred to as one pair, but are not limited thereto.

The first dielectric layer 101 and the second dielectric layer 103 may be formed using, for example, a sputtering process or a deposition process, but are not limited thereto.

The side surface of the blocking pattern 43 including the plurality of first dielectric layers 101 and the plurality of second dielectric layers 103 may include any one of a vertical surface, an inclined surface, a round surface, and an uneven surface with respect to the light emitting structure. This is not limitative.

The inclined surface of the blocking pattern 43 may have an acute angle of 20 ° to 90 ° with respect to the upper surface of the light emitting structure, but is not limited thereto.

Therefore, the light generated from the light emitting structure, specifically the active layer, is reflected by the current blocking layer 42 or the blocking pattern 43 and proceeds into the light emitting structure, and the light is externally directed through the side of the light emitting structure. Since it is emitted, the luminous efficiency of the light emitting device can be improved.

When viewed from the side, the blocking pattern 43 may include a sphere, a rectangle, a polygon, and the like, but is not limited thereto. The blocking pattern 43 may have a left-right symmetrical structure or a left-right asymmetrical structure with respect to a vertical normal when viewed from the side, but is not limited thereto.

The distance d between the blocking patterns 43 may be, for example, 5 μm to 1000 μm in consideration of the minimum error range in the mask patterning of the light emitting device and the concentration of the current, but is not limited thereto. For example, the distance d between the blocking patterns 43 may be 30 μm to 100 μm, but is not limited thereto.

The current spreading layer 44 may be formed on the current blocking layer 42. The current spreading layer 44 may include a plurality of diffusion patterns 45, but is not limited thereto. Each of the diffusion patterns 45 may be formed to surround each of the blocking patterns 43. The diffusion pattern 45 may be formed to contact the upper surface of the light emitting structure, the outer surface of the blocking pattern 43, and the upper surface of the blocking pattern 43, but is not limited thereto.

The electrode layer 46 may be formed in contact with the top surface of the light emitting structure and the top surface of each diffusion pattern 45 between the blocking patterns 43, but is not limited thereto.

The electrode pattern 46, the diffusion pattern 45 of the current diffusion layer 44, and the blocking pattern 43 of the current blocking layer 42 may have a circular shape as shown in FIG. 7 or as shown in FIG. 8. It can have a square, but not limited thereto.

The electrode layer 46 formed to contact the upper surface of the light emitting structure between the blocking patterns 43, that is, the lower portion of the electrode layer 46 may be surrounded by the diffusion pattern 45, but is not limited thereto.

9 is a view showing an electrode structure according to a fourth embodiment.

The fourth embodiment is almost similar to the third embodiment except that a plurality of blocking patterns 43 of the current blocking layer 42 are formed in the foot and the structure. Therefore, in the fourth embodiment, the same reference numerals are assigned to components having the same shape or the same function as the third embodiment, and detailed description thereof will be omitted. Content not described in the fourth embodiment will be easily understood from the third embodiment.

9, the electrode structure 40 according to the third embodiment includes a current blocking layer 42 formed on the light emitting structure, and a current diffusion layer 44 formed on the light emitting structure and the current blocking layer 42. And an electrode layer 46 formed on at least the current blocking layer 42.

Since the current blocking layer 42, the current spreading layer 44, and the electrode layer 46 have been described above, a brief description thereof will be provided below.

A plurality of grooves may be formed on the upper surface of the light emitting structure. The groove may be a groove having the upper surface of the foot and the structure removed to a certain depth from the upper surface.

Since the groove corresponds to the shape of the current blocking layer 42 shown in FIGS. 7 and 8, specifically, the diffusion pattern 45, the groove may be circular or quadrangle when viewed from above, but is not limited thereto.

The inner surface of the groove may include any one of a vertical surface, an inclined surface, a round surface, and an uneven surface with respect to the upper surface of the light emitting structure, but is not limited thereto.

A plurality of blocking patterns 43 of the current blocking layer 42 may be formed in the plurality of grooves. The top surface of the blocking pattern 43 may completely fill the groove and coincide with the top surface of the light emitting structure, but is not limited thereto.

The diffusion pattern 45 of the current diffusion layer 44 may be formed in contact with the top surface of the blocking pattern 43. The diffusion pattern 45 may be formed on the same line as the current diffusion layer 44, but is not limited thereto.

1 to 9 may be used as the horizontal type light emitting device of FIG. 10 or the flip type light emitting device of FIG. 11, but embodiments of the present invention are not limited thereto.

10 is a cross-sectional view showing a horizontal light emitting device according to the first embodiment.

Referring to FIG. 10, the horizontal light emitting device 1 according to the first embodiment may include a substrate 10, a light emitting structure 20, and first and second electrodes 30 and 32. It is not limited.

The light emitting structure 20 may include, but is not limited to, a first conductive semiconductor layer 12, an active layer 15, and a second conductive semiconductor layer 18.

The first and second electrode structures 30 and 32 may have the same shape and the same function as the structure of the electrode structure 40 shown in FIG. 1. Therefore, a detailed description of the first and second electrode structures 30 and 32 will be omitted, and the descriptions below will be readily understood from the foregoing description.

That is, each of the first and second electrode structures 30 and 32 may include a current blocking layer 42, a current diffusion layer 44, and an electrode layer 46.

The current blocking layer 42 may include a plurality of blocking patterns, and the current spreading layer 44 may include a plurality of diffusion patterns.

A blocking pattern of the first electrode structure 30 is formed on the first conductive semiconductor layer 12, and a blocking pattern of the second electrode structure 32 is formed on the second conductive semiconductor layer 18. Can be formed on.

Each of the diffusion patterns of the first electrode structure 30 is formed on the blocking pattern of the first electrode structure 30, and the electrode layer 46 of the first electrode structure 30 is formed of the first electrode structure ( 30 may be formed on the top surface of the first conductivity-type semiconductor layer and the top surface of the diffusion pattern of the first electrode structure 30 between the blocking patterns of the substrate 30 and the diffusion pattern of the first electrode structure 30.

Each diffusion pattern of the second electrode structure 32 is formed on a blocking pattern of the second electrode structure 32, and the electrode layer 46 of the second electrode structure 32 is the second electrode structure 32. ) May be formed on the top surface of the second conductive semiconductor layer and the top surface of the diffusion pattern of the second electrode structure 32 between the blocking patterns of the second electrode structure and the diffusion pattern of the second electrode structure 32.

The current spreading layer 44 of the horizontal light emitting device 1 according to the first embodiment may be a transparent layer including a transparent conductive material, but is not limited thereto.

Examples of the transparent conductive material include ITO, IZO (In-ZnO), GZO (Ga-ZnO), AZO (Al-ZnO), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), IrOx, RuOx. At least one selected from the group consisting of RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO.

In the horizontal light emitting device 1 according to the first embodiment, light generated in the active layer of the light emitting structure 20 is transferred to the outside through the transparent conductive layers of the first and second electrode structures 30 and 32. Can be exited.

The horizontal light emitting device 1 according to the first embodiment may further include a buffer layer disposed between the substrate 10 and the light emitting structure 20.

The horizontal light emitting device 1 according to the first exemplary embodiment may further include another semiconductor layer (not shown) disposed below and / or above the light emitting structure 20.

The horizontal light emitting device 1 according to the first embodiment may further include an undoped semiconductor layer (not shown) disposed between the buffer layer and the light emitting structure 20.

The substrate 10 serves to easily grow the light emitting structure 20, but is not limited thereto.

In order to stably grow the light emitting structure 20, the substrate 10 may be formed of a material having a small lattice constant with the light emitting structure 20 as small as possible.

The substrate 10 may be formed of at least one selected from the group consisting of sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, and Ge.

The buffer layer may be disposed between the substrate 10 and the light emitting structure 20. The buffer layer may be formed to alleviate the lattice constant difference between the substrate 10 and the light emitting structure 20.

Each of the buffer layer and the light emitting structure 20 may be formed of a II-VI compound semiconductor material.

The light emitting structure 20 may be formed on any one of the substrate 10, the buffer layer, and the undoped semiconductor layer.

The light emitting structure 20 may include, for example, a first conductive semiconductor layer 12, an active layer 15, and a second conductive semiconductor layer 18. The first conductivity type semiconductor layer 12 is formed on any one of the substrate 10, the buffer layer and the undoped semiconductor layer, and the active layer 15 is formed on the first conductivity type semiconductor layer 12. The second conductive semiconductor layer 18 may be formed on the active layer 15.

The first conductivity-type semiconductor layer 12 may be, for example, an n-type semiconductor layer including an n-type dopant. The first conductive semiconductor layer 12 is a semiconductor material having a compositional formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1), For example, it may include at least one selected from the group consisting of InAlGaN, GaN, AlGaN, InGaN, AlN, InN, and AlInN, and an n-type dopant such as Si, Ge, Sn, or the like may be doped.

The active layer 15 may be formed on the first conductivity type semiconductor layer 12.

The active layer 15 combines a first carrier, for example, electrons injected through the first conductivity type semiconductor layer 12, and a second carrier, for example, holes injected through the second conductivity type semiconductor layer 18, to each other. The light emitting layer may emit light having a wavelength corresponding to a band gap of an energy band according to a material forming the active layer 15.

The active layer 15 may include any one of a multi quantum well structure (MQW), a quantum dot structure, or a quantum line structure. The active layer 15 may be formed by repeating group II-VI compound semiconductors in a cycle of a well layer and a barrier layer.

For example, it may be formed by a period of the InGaN well layer / GaN barrier layer, a period of the InGaN well layer / AlGaN barrier layer, or a period of the InGaN well layer / InGaN barrier layer. The band gap of the barrier layer may be larger than the band gap of the well layer.

The second conductivity type semiconductor layer 18 may be formed on the active layer 15. The second conductive semiconductor layer 18 may be, for example, a p-type semiconductor layer including a p-type dopant. The p-type semiconductor layer is a semiconductor material having a composition formula of In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1), for example, InAlGaN, It may include at least one selected from the group consisting of GaN, AlGaN, InGaN, AlN, InN, and AlInN, and may be doped with p-type dopants such as Mg, Zn, Ca, Sr, and Ba.

The transparent conductive layer 22 may be formed on the second conductive semiconductor layer 18, and the second electrode 32 may be formed in a portion of the transparent conductive layer 22.

The first electrode 30 may be formed in a portion of the first conductive semiconductor layer 12 of the light emitting structure 20. To this end, the second conductive semiconductor layer 18 and the active layer 15 may be removed by a mesa etching, and a portion of the upper surface of the first conductive semiconductor layer 12 may be removed. The first electrode 30 may be formed on the first conductive semiconductor layer 12 removed as described above.

The second electrode 32 is formed on the top of the horizontal light emitting device 1, and the first electrode 30 is formed on the side of the horizontal light emitting device 1, so that the first and second electrodes When power is applied to the 30 and 32, electric current flows to the light emitting structure 20 corresponding to the shortest path between the first and second electrodes 30 and 32, so that the front of the active layer 15 of the light emitting structure 20 is removed. Light emission may not occur in the region.

Accordingly, by forming the transparent conductive layer 22 on the entire area of the second conductive semiconductor layer 18 between the second conductive semiconductor layer 18 and the second electrode 32, the second conductive semiconductor layer 18 is formed. The current is spread to the entire region of the transparent conductive layer 22 through the electrode 32 so that a current flows between the first electrode 30 and the entire region of the transparent electrode so that the active layer 15 of the light emitting structure 20 is active. Luminescence can be emitted in all regions of the to improve luminous efficiency.

The transparent conductive layer 22 is formed of a conductive material having excellent light transmittance and electrical conductivity, for example, ITO, IZO (In-ZnO), GZO (Ga-ZnO), AZO (Al-ZnO), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), IrOx, RuOx, RuOx / ITO, Ni / IrOx / Au and Ni / IrOx / Au / ITO.

11 is a cross-sectional view illustrating a flip light emitting device according to a second embodiment.

The second embodiment is almost similar to the first embodiment except that the current spreading layer 44 including the reflective material is formed instead of the current spreading layer 44 including the transparent conductive material of the first embodiment. Therefore, in the second embodiment, the same reference numerals are assigned to components having the same shape and the same function as the first embodiment, and detailed description thereof will be omitted.

Referring to FIG. 11, the flip type light emitting device 1A according to the second exemplary embodiment may include a substrate 10, a light emitting structure 20, and first and second electrode structures 34 and 36. It is not limited.

The light emitting structure 20 may include, but is not limited to, a first conductive semiconductor layer 12, an active layer 15, and a second conductive semiconductor layer 18.

The first conductive semiconductor layer 12 is formed under the substrate 10, the active layer 15 is formed under the first conductive semiconductor layer 12, and under the active layer 15. The second conductivity type semiconductor layer 18 may be formed on the substrate.

The first electrode structure 34 may be formed under the first conductive semiconductor layer 12, and the second electrode structure 36 may be formed under the reflective layer 24.

The first and second electrode structures 34 and 36 may have substantially the same structure or shape as the first and second electrodes 30 and 32 of the first embodiment.

Each of the first and second electrode structures 34 and 36 may include a current blocking layer 42 including a plurality of blocking patterns, a current spreading layer 44 including a plurality of diffusion patterns, and an electrode layer 46. have.

The current spreading layer 44 of the flip type light emitting device 1A according to the second embodiment may be, for example, a reflective layer including a reflective conductive material, but is not limited thereto.

For example, at least one or two or more alloys selected from the group consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf may be used as the reflective conductive material. Do not.

In the flip type light emitting device according to the second embodiment, light generated in the active layer of the light emitting structure 20 may be reflected by the current diffusion layer 44 and emitted to the outside through the first conductive semiconductor layer.

Since the contents of the first and second electrode structures 34 and 36 are substantially the same as those of the electrode structures 40 illustrated in FIGS. 1 to 9, further description thereof will be omitted.

12 is a cross-sectional view illustrating a light emitting device package according to an embodiment.

Referring to FIG. 12, the light emitting device package according to the embodiment may include a body 101, a first lead electrode 103 and a second lead electrode 105 installed on the body 101, and the body 101. A light emitting element 1 according to the first and second embodiments, which is installed and supplied with power from the first lead electrode 103 and the second lead electrode 105, and surrounds the light emitting element 1. It includes a molding member 113.

The body 101 may include a silicon material, a synthetic resin material, or a metal material, and an inclined surface may be formed around the light emitting device 1.

The first lead electrode 103 and the second lead electrode 105 are electrically separated from each other, and provide power to the light emitting device 1.

In addition, the first and second lead electrodes 103 and 105 may increase light efficiency by reflecting light generated from the light emitting device 1, and heat generated from the light emitting device 1 to the outside. It can also play a role.

The light emitting device 1 may be installed on any one of the first lead electrode 103, the second lead electrode 105, and the body 101. The light emitting device 1 may be formed by a wire method, a die bonding method, or the like. It may be electrically connected to the second lead electrodes 103 and 105, but is not limited thereto.

In the embodiment, it is illustrated that the light emitting device 1 is electrically connected to one of the first and second lead electrodes 103 and 105 through one wire 109, but is not limited thereto. The light emitting device 1 may be electrically connected to the first and second lead electrodes 103 and 15 using two wires, and the light emitting device 1 may be connected to the first and second lead without using a wire. It may be electrically connected to the electrodes 103 and 105.

The molding member 113 may surround the light emitting device 1 to protect the light emitting device 1. In addition, the molding member 113 may include a phosphor to change the wavelength of light emitted from the light emitting device 1.

The light emitting device package 200 according to the embodiment may include a chip on board (COB) type, the upper surface of the body 101 is flat, and a plurality of light emitting devices may be installed on the body 101.

The light emitting device or the light emitting device package according to the embodiment may be applied to the light unit. The light unit may be applied to a unit such as a display device and a lighting device, such as a lighting lamp, a traffic light, a vehicle headlight, an electric sign, an indicator lamp.

10: Substrate
12: first conductive semiconductor layer
15: active layer
18: second conductivity type semiconductor layer
20: light emitting structure
30, 32, 34, 36, 40: electrode structure
42: current blocking layer
44: current diffusion layer
46: electrode layer 46
101: first dielectric layer
103: second dielectric layer

Claims (12)

Light emitting structure; And
At least one electrode structure in contact with the light emitting structure,
The at least one electrode structure,
A current blocking layer in contact with the light emitting structure and including a plurality of blocking patterns;
A current diffusion layer disposed on the current blocking layer and including a plurality of diffusion patterns; And
An electrode layer disposed on the current spreading layer and penetrating the current spreading layer to be formed on the light emitting structure;
The light emitting structure includes a groove removed to a predetermined depth from the upper surface of the light emitting structure,
The plurality of blocking patterns are disposed in the groove,
The top surface of the blocking pattern is disposed on the same plane as the top surface of the light emitting structure,
The lower surface of the diffusion pattern is disposed on the same plane as the upper surface of the light emitting structure,
The lower region of the electrode layer disposed between the blocking patterns and in contact with the light emitting structure is surrounded by the diffusion pattern. The method of claim 1,
The light emitting device may include a light emitting device surrounding a side circumference and a bottom surface of the blocking pattern. The method according to claim 1 or 2,
The current diffusion layer is a light emitting device that is a transparent conductive material or a reflective material. The method according to claim 1 or 2,
The current blocking layer includes a plurality of first and second dielectric layers alternately stacked with different refractive indices. delete The method according to claim 1 or 2,
The width of the diffusion pattern is equal to or larger than the width of the blocking pattern,
The interval between the blocking pattern is a light emitting device 5㎛ to 1000㎛. delete delete delete delete delete delete

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