KR102365836B1 - Light emitting device, and light emitting device array including the same - Google Patents

Abstract

The light emitting device of the embodiment includes a substrate, a non-conductive layer disposed in the substrate, and a material of the same type as the substrate, and a light emitting structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer disposed on the substrate include

Description

Light emitting device and light emitting device array including same {Light emitting device, and light emitting device array including the same}

The embodiment relates to a light emitting device and a light emitting device array including the same.

Light emitting devices such as light emitting diodes and laser diodes using group III-V or group II-VI compound semiconductor materials of semiconductors have developed various colors such as red, green, blue and ultraviolet light through thin film growth technology and development of device materials. can be implemented. In addition, the light emitting device can realize efficient white light by combining colors using fluorescent materials, and has advantages of low power consumption, semi-permanent lifespan, fast response speed, safety, and environmental friendliness compared to conventional light sources such as fluorescent lamps and incandescent lamps. have

Therefore, the transmission module of optical communication means, the light emitting diode backlight that replaces the Cold Cathode Fluorescence Lamp (CCFL) constituting the backlight of the liquid crystal display (LCD), the fluorescent lamp or the incandescent bulb can be replaced. The application of light emitting devices is expanding to white light emitting diode lighting devices, automobile headlights, and traffic lights.

Although not shown, a conventional light emitting device includes a substrate and a light emitting structure disposed on the substrate. The light emitting structure may include an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. At this time. When the substrate and the light emitting structure are implemented with different types of materials, reliability problems may occur.

The embodiment provides a light emitting device having improved reliability and a light emitting device array including the same.

A light emitting device according to an embodiment includes: a substrate; a non-conductive layer disposed within the substrate; and a light emitting structure comprising the same material as the substrate and including a first conductivity-type semiconductor layer, an active layer, and a second conductivity-type semiconductor layer disposed on the substrate.

For example, the non-conductive layer includes an ion-implanted layer, the ion-implanted layer includes at least one of Mg, Zn, C, and oxygen ions, and the minimum thickness of the non-conductive layer is 10 nm; The substrate may be polar, semi-polar or non-polar.

For example, the light emitting device may include: a first electrode disposed on the first conductivity type semiconductor layer exposed by mesa etching the second conductivity type semiconductor layer and the active layer; and a second electrode disposed on the second conductivity-type semiconductor layer. The substrate may include an upper portion disposed between the non-conductive layer and the light emitting structure; and a lower portion disposed under the non-conductive layer. A thickness of the upper portion may be smaller than a thickness of the lower portion, the same as a thickness of the lower portion, or greater than a thickness of the lower portion.

For example, the light emitting device may further include a light extraction structure disposed on the emitting surface of the substrate from which the light emitted from the active layer is emitted. The light emitting device may include a first electrode under the substrate; and a second electrode on the second conductivity-type semiconductor layer.

For example, the non-conductive layers may be disposed to be spaced apart from each other in a direction perpendicular to a thickness direction of the light emitting structure. Each of the substrate and the light emitting structure may include GaN.

A light emitting device array according to another embodiment includes: a substrate; a non-conductive layer disposed within the substrate; and a plurality of light emitting cells arranged in a horizontal direction on the substrate. and a conductivity-type interconnection part electrically connecting two light-emitting cells of the plurality of light-emitting cells, wherein each of the light-emitting cells includes a material of the same type as that of the substrate, and a first conductivity-type semiconductor layer disposed on the substrate , a light emitting structure including an active layer and a second conductivity type semiconductor layer.

For example, the first conductivity type semiconductor layer of the plurality of light emitting cells may be integrated.

For example, each of the light emitting cells may include a first electrode connected to the first conductivity type semiconductor layer exposed by mesa-etching the second conductivity type semiconductor layer and the active layer; and a second electrode connected to the second conductivity-type semiconductor layer.

The light emitting device according to the embodiment has excellent thermal and electrical conductivity by implementing the substrate and the light emitting structure with the same material, and has a much lower defect density compared to the heterogeneous substrate, so that it has excellent durability and light extraction efficiency in a high current, high temperature and/or high humidity environment may have, and the light emitting device array according to the embodiment is suitable for miniaturization, weight reduction, and low price, but reliability can be secured in a high current, high temperature and/or high humidity environment when driven by an AC voltage, and the vision inside the substrate By disposing the coating layer, the problem of current leakage can be eliminated.

1 is a cross-sectional view of a light emitting device according to an embodiment.
2 is a cross-sectional view of a light emitting device according to another embodiment.
3 is a cross-sectional view of a light emitting device according to another embodiment.
4 is a cross-sectional view of a light emitting device according to another embodiment.
5 is a cross-sectional view of a light emitting device array according to an embodiment.
FIG. 6 is a circuit diagram of the light emitting device array shown in FIG. 5 .
FIG. 7 is a circuit diagram of the light emitting device array shown in FIG. 5 .
8A to 8F are cross-sectional views illustrating a method of manufacturing the light emitting device shown in FIG. 1 according to the embodiment.
9 is a cross-sectional view of a light emitting device package according to an embodiment.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings to help the understanding of the present invention by giving examples and to explain the present invention in detail. However, embodiments according to the present invention may be modified in various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided in order to more completely explain the present invention to those of ordinary skill in the art.

In the description of this embodiment, in the case of being described as being formed on "on or under" of each element, above (above) or below (below) ( on or under includes both elements in which two elements are in direct contact with each other or in which one or more other elements are disposed between the two elements indirectly.

In addition, when expressed as "up (up)" or "down (on or under)", the meaning of not only an upward direction but also a downward direction may be included based on one element.

Also, as used hereinafter, relational terms such as “first” and “second,” “top/top/top” and “bottom/bottom/bottom” refer to any physical or logical relationship between such entities or elements or It may be used only to distinguish one entity or element from another, without requiring or implying an order.

1 is a cross-sectional view of a light emitting device 100A according to an embodiment.

The light emitting device 100A illustrated in FIG. 1 may include a substrate 110 , a non-conductive layer 120A, a light emitting structure 130 , and first and second electrodes 142A and 144A.

The substrate 110 may include at least one of GaN, SiC, ZnO, GaP, InP, Ga ₂ O ₃ , GaAs, or Si. If the substrate 110 and the light emitting structure 130 to be described later can be implemented with the same type of material as each other, the embodiment is not limited to the type of the substrate 110 .

The substrate 110 may be polar, semi-polar, or non-polar, and the embodiment is not limited to the polarity of the substrate 110 .

The non-conductive layer 120A may be disposed in the substrate 110 . The non-conductive layer 120A may include an ion implantation layer. The ion implantation layer may be formed by implanting at least one ion of Mg, Zn, C, or oxygen ions.

When the first thickness T1 of the non-conductive layer 120A is less than 10 nm, the role of the non-conductive layer 120A in blocking the conductivity of the substrate 110 may be weak due to the tunneling effect. Accordingly, the minimum value of the first thickness T1 of the non-conductive layer 120A may be 10 nm, but the embodiment is not limited thereto.

The non-conductive layer 120A may be located above, below, or in the middle of the substrate 110 , and the embodiment is not limited to the position of the non-conductive layer 120A in the substrate 110 .

The substrate 110 may include a lower portion 112 and an upper portion 114 . The upper part 114 may be disposed between the non-conductive layer 120A and the light emitting structure 130 , and the lower part 112 may be disposed below the non-conductive layer 120A.

The non-conductive layer 120A may be disposed on the substrate 110 . In this case, the second thickness T2 of the upper portion 114 may be smaller than the third thickness T3 of the lower portion 112 .

Alternatively, the non-conductive layer 120A may be disposed in the middle of the substrate 110 . In this case, the second thickness T2 of the upper portion 114 and the third thickness T3 of the lower portion 112 may be the same.

Alternatively, the non-conductive layer 120A may be disposed below the substrate 110 . In this case, the second thickness T2 of the upper portion 114 may be greater than the third thickness T3 of the lower portion 112 .

If the non-conductive layer 120A is disposed on the lower side of the substrate 110 , when the lower surface of the substrate 110 is polished, the non-conductive layer 120A is also polished and lost, so that the non-conductivity of the substrate 110 is lost. This can be weak. Accordingly, it may be advantageous to dispose the non-conductive layer 120A on the upper side of the substrate 110 rather than the lower side.

Meanwhile, the light emitting device 100A may further include a first conductivity-type intermediate layer 150 disposed between the light emitting structure 130 and the substrate 110 . The first conductivity-type intermediate layer 150 may serve to facilitate the formation of the light emitting structure 130 on the substrate 110 . In some cases, the first conductivity type intermediate layer 150 may be omitted. The first conductivity-type intermediate layer 150 may be made of the same material as the substrate 110 , but the embodiment is not limited thereto. If the first conductivity-type semiconductor layer 132 is an n-type semiconductor layer, the first conductivity-type intermediate layer 150 may be implemented as an n-type GaN layer.

The light emitting structure 130 may be implemented with the same material as the substrate 110 . For example, each of the light emitting structure 130 and the substrate 110 may be implemented with GaN.

The light emitting structure 130 may include a first conductivity type semiconductor layer 132 , an active layer 134 , and a second conductivity type semiconductor layer 136 disposed on the substrate 110 . The first conductivity type semiconductor layer 132 , the active layer 134 , and the second conductivity type semiconductor layer 136 may be sequentially stacked on the substrate 110 .

The first conductivity-type semiconductor layer 132 is disposed on the substrate 110 and may be implemented as a compound semiconductor such as III-V group or II-VI group doped with a first conductivity-type dopant. may be doped. When the first conductivity-type semiconductor layer 132 is an n-type semiconductor layer, the first conductivity-type dopant is an n-type dopant and may include Si, Ge, Sn, Se, and Te, but is not limited thereto.

For example, the first conductivity type semiconductor layer 132 has a composition formula of Al _x In _y Ga _(1-xy) N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) It may include a semiconductor material. The first conductivity type semiconductor layer 132 may include any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP.

The active layer 134 may be disposed between the first conductivity type semiconductor layer 132 and the second conductivity type semiconductor layer 136 . In the active layer 134, electrons (or holes) injected through the first conductivity type semiconductor layer 132 and holes (or electrons) injected through the second conductivity type semiconductor layer 136 meet each other, and the active layer ( 134) is a layer that emits light with energy determined by the intrinsic energy band of the material.

The active layer 134 may include at least one of a single well structure, a multi-well structure, a single quantum well structure, a multi quantum well (MQW) structure, a quantum-wire structure, or a quantum dot structure. can be formed into one.

The well layer/barrier layer of the active layer 134 may have a pair structure of any one or more of InGaN/GaN, InGaN/InGaN, GaN/AlGaN, InAlGaN/GaN, GaAs (InGaAs)/AlGaAs, and GaP (InGaP)/AlGaP. However, the present invention is not limited thereto. The well layer may be formed of a material having a bandgap energy lower than the bandgap energy of the barrier layer.

A conductive cladding layer (not shown) may be formed on and/or below the active layer 134 . The conductive cladding layer may be formed of a semiconductor having a higher bandgap energy than that of the barrier layer of the active layer 134 . For example, the conductive clad layer may include GaN, AlGaN, InAlGaN, or a superlattice structure. In addition, the conductivity-type cladding layer may be doped with n-type or p-type.

The second conductivity type semiconductor layer 136 may be disposed on the active layer 134 . The second conductivity type semiconductor layer 136 may be formed of a semiconductor compound. It may be implemented as a compound semiconductor of group III-V or group II-VI. For example, the second conductivity type semiconductor layer 136 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) may include The second conductivity type semiconductor layer 136 may be doped with a second conductivity type dopant. When the second conductivity-type semiconductor layer 136 is a p-type semiconductor layer, the second conductivity-type dopant is a p-type dopant and may include Mg, Zn, Ca, Sr, Ba, or the like.

The first conductivity-type semiconductor layer 132 may be implemented as a p-type semiconductor layer, and the second conductivity-type semiconductor layer 136 may be implemented as an n-type semiconductor layer. Alternatively, the first conductivity-type semiconductor layer 132 may be implemented as an n-type semiconductor layer, and the second conductivity-type semiconductor layer 136 may be implemented as a p-type semiconductor layer.

The light emitting structure 130 may be implemented as any one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

In addition, an electron blocking layer (EBL) (not shown) may be further disposed between the active layer 134 and the second conductivity type semiconductor layer 136 . The electron blocking layer EBL may have a superlattice structure. In the superlattice, for example, AlGaN doped with a second conductivity type dopant may be disposed, and a plurality of GaN layers having different aluminum composition ratios may be alternately disposed.

Meanwhile, the first electrode 142A may be disposed on the first conductivity type semiconductor layer 132 exposed by mesa etching the second conductivity type semiconductor layer 136 and the active layer 134 . The second electrode 144A may be disposed on the second conductivity-type semiconductor layer 136 . Each of the first and second electrodes 142A and 144A includes, for example, at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (Au). It may have a single-layered or multi-layered structure.

Also, a first ohmic contact layer (not shown) may be disposed between the first electrode 142A and the first conductivity-type semiconductor layer 132 . The first ohmic contact layer serves to improve the ohmic characteristics of the first conductivity-type semiconductor layer 132 . For example, the first ohmic contact layer may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), or IGTO ( indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), ZnO , IrOx, RuOx, NiO, RuOx/ITO, Ni/IrOx/Au, and Ni/IrOx/Au/ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, Ru, Mg, It may be formed including at least one of Zn, Pt, Au, and Hf, but is not limited to these materials.

In addition, a second ohmic contact layer (not shown) may be disposed between the second electrode 144A and the second conductivity-type semiconductor layer 136 . The second ohmic contact layer serves to improve the ohmic characteristics of the second conductivity type semiconductor layer 136 . When the second conductivity type semiconductor layer 136 is a p-type semiconductor layer, the contact resistance is high due to the low impurity doping concentration of the second conductivity type semiconductor layer 136 , and thus the ohmic characteristics may be poor. may play a role in improving these ohmic characteristics.

2 is a cross-sectional view of a light emitting device 100B according to another embodiment.

The light emitting device 100B shown in FIG. 2 includes a substrate 110 , a non-conductive layer 120B, a first conductive intermediate layer 150 , a light emitting structure 130 , and first and second electrodes 142B and 144B. may include

The light emitting device 100A shown in FIG. 1 has a horizontal bonding structure, whereas the light emitting device 100B shown in FIG. 2 has a vertical bonding structure. Accordingly, the arrangement structure of the first and second electrodes 142A and 144A in the light emitting device 100A shown in FIG. 1 and the first and second electrodes 142B and 144B in the light emitting device 100B shown in FIG. 2 . may have different layout structures.

That is, in the light emitting device 100B shown in FIG. 2 , the first electrode 142B may be disposed under the substrate 110 . The second electrode 144B may be disposed on the second conductivity-type semiconductor layer 136 . Each of the first and second electrodes 142B and 144B includes, for example, at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (Au). It may have a single-layered or multi-layered structure.

In addition, the non-conductive layer 120A shown in FIG. 1 is integrally implemented in a direction (eg, x-axis direction) perpendicular to the thickness direction (eg, y-axis direction) of the light emitting structure 130 . , the non-conductive layer 120B shown in FIG. 2 may be disposed to be spaced apart from each other in a direction perpendicular to the thickness direction of the light emitting structure 130 . Alternatively, the non-conductive layer 120B shown in FIG. 2 is integrally implemented like the non-conductive layer 120A shown in FIG. 1 , and the carrier supplied through the first electrode 142B proceeds to the active layer 134 . It may have a through hole 124 so that

Except for the above differences, the light emitting device 100B shown in FIG. 2 may be the same as the light emitting device 100A shown in FIG. 1 . Therefore, the first conductivity type semiconductor layer 132 , the active layer 134 , and the second conductivity type semiconductor layer 136 of the light emitting structure 130 shown in FIG. Each of the first conductivity type semiconductor layer 132 , the active layer 134 , and the second conductivity type semiconductor layer 136 performs the same role and may be formed of the same material. Also, since the first conductivity-type intermediate layer 150 illustrated in FIG. 2 is the same as the first conductivity-type intermediate layer 150 illustrated in FIG. 1 , the same reference numerals are used, and a description thereof will be omitted.

Like the substrate 110 of the light emitting device 100A shown in FIG. 1 , the substrate 110 of the light emitting device 100B shown in FIG. 2 has an upper portion 114 and a lower portion 112 . In addition, the non-conductive layer 120B may be disposed above, below, or in the middle of the substrate 110 .

Also, just as the substrate 110 and the light emitting structure 130 shown in FIG. 1 are implemented with the same material as each other, the substrate 110 and the light emitting structure 130 shown in FIG. 2 are also implemented with the same material. can be

3 is a cross-sectional view of a light emitting device 100C according to another embodiment.

The light emitting device 100C shown in FIG. 3 includes a substrate 110 , a non-conductive layer 120C, a light emitting structure 130 , first and second electrodes 142A and 144A, a first conductive intermediate layer 150 and A light extraction structure 160A may be included.

In the case of the light emitting device 100A shown in FIG. 1 , the light emitted from the active layer 134 passes through the second conductivity-type semiconductor layer 136 and the second electrode 144A in the upper direction (eg, in the y-axis direction). can be released as On the other hand, in the case of the light emitting device 100C shown in FIG. 3 , light emitted from the active layer 134 is non-conductive with the first conductivity type semiconductor layer 132 , the first conductivity type intermediate layer 150 , and the substrate 110 . It may be emitted in an upper direction (eg, a y-axis direction) through the layer 120C.

At this time, unlike the light emitting device 100A shown in FIG. 1 , the light emitting device 100C shown in FIG. 3 has a light extraction disposed on the light emitting surface of the substrate 110 from which the light emitted from the active layer 134 is emitted. A structure 160A may be further included. When the light extraction structure 160A is disposed, more light from the light exit surface of the substrate 110 may escape from the light emitting device 100C.

As described above, the light emitting device 100C shown in FIG. 3 has a shape in which the light emitting device 100A shown in FIG. 1 is turned over, and unlike the light emitting device 100A shown in FIG. 1 , the light extraction structure 160A is may include more. Except for this, since the light emitting device 100C shown in FIG. 3 is the same as the light emitting device 100A shown in FIG. 1 , overlapping descriptions of the same parts will be omitted.

In addition, in the case of the light emitting device 100A shown in FIG. 1 , light is emitted through the second conductivity-type semiconductor layer 136 and the second electrode 144A, so that these 136 and 144A are implemented with a material having light transmittance. can be However, in the case of the light emitting device 100C shown in FIG. 3 , light is emitted through the first conductivity-type semiconductor layer 132 , the substrate 110 , and the non-conductive layer 120C. Accordingly, these layers 132 , 110 , and 120C shown in FIG. 3 may be implemented with a light-transmitting material.

4 is a cross-sectional view of a light emitting device 100D according to another embodiment.

The light emitting device 100D illustrated in FIG. 4 includes a substrate 110 , a non-conductive layer 120B, a light emitting structure 130 , first and second electrodes 142B and 144B, a first conductive intermediate layer 150 and A light extraction structure 160B may be included.

In the case of the light emitting device 100B shown in FIG. 2 , the light emitted from the active layer 134 passes through the second conductivity-type semiconductor layer 136 and the second electrode 144B in the upper direction (eg, in the y-axis direction). can be released as On the other hand, in the case of the light emitting device 100D shown in FIG. 4 , light emitted from the active layer 134 is non-conductive with the first conductivity type semiconductor layer 132 , the first conductivity type intermediate layer 150 , and the substrate 110 . It may be emitted in an upper direction (eg, a y-axis direction) through the layer 120B and the first electrode 142B.

In this case, the light extraction structure 160B may be further disposed on the light exit surface of the substrate 110 from which the light emitted from the active layer 134 is emitted. When the light extraction structure 160B is disposed, more light from the light exit surface of the substrate 110 may escape from the light emitting device 100D.

In addition, in the case of FIG. 4 , it is illustrated that the light extraction structure 160B is not disposed on the portion where the first electrode 142B is disposed among the light exit surface of the substrate 110 , but the embodiment is not limited thereto. That is, according to another embodiment, the light extraction structure 160B may be further disposed between the first electrode 142B and the substrate 110 .

As described above, the light emitting device 100D shown in FIG. 4 has an inverted shape of the light emitting device 100B shown in FIG. 2 , and unlike the light emitting device 100B shown in FIG. 2 , the light extraction structure 160B may include more. Except for this, since the light emitting device 100D shown in FIG. 4 is the same as the light emitting device 100B shown in FIG. 2 , overlapping descriptions of the same parts will be omitted.

In addition, in the case of the light emitting device 100B shown in FIG. 2 , since light is emitted through the second conductivity-type semiconductor layer 136 and the second electrode 144B, these 136 and 144B are implemented with a light-transmitting material. do. However, in the case of the light emitting device 100D shown in FIG. 4 , light is emitted from the first conductive semiconductor layer 132 , the first conductive intermediate layer 150 , the substrate 110 , the non-conductive layer 120B and the first electrode. It is emitted through (142B). Accordingly, these layers 132 , 150 , 110 , 120B and 142B shown in FIG. 4 may be implemented with a light-transmitting material.

On the other hand, in each of the light emitting devices 100A, 100B, 100C, and 100D according to the above-described embodiment, when the substrate 110 and the light emitting structure 130 are implemented with a different material, the light emitting devices 100A to 100D exist in the light emitting devices 100A to 100D. Due to the high defect density, it may be difficult to ensure reliability during high current driving, high temperature, and/or driving in a high humidity environment.

If the light emitting structure 130 is implemented with GaN and the substrate 110 is made of sapphire, since the sapphire is transparent, light efficiency may be more advantageous than when the substrate 110 is implemented with an opaque material such as silicon. However, when the substrate 110 is implemented with a different type of sapphire than the light emitting structure 130 , there is a problem in that high temperature and/or high current driving is limited due to the low thermal conductivity of sapphire.

However, as in the above-described embodiment, when the substrate 110 and the light emitting structure 130 are made of the same material, these problems can be solved. That is, when the light emitting structure 130 is implemented with GaN, the substrate 110 implemented with the same type of GaN has excellent thermal and electrical conductivity, and has a much lower defect density compared to a heterogeneous substrate, so that a high current, high temperature and/or high humidity It has excellent durability and light extraction efficiency in one environment.

Hereinafter, the light emitting device arrays 200A and 200B including the light emitting device 100A according to the above-described embodiment as a light emitting cell will be described with reference to the accompanying drawings.

5 is a cross-sectional view of a light emitting device array 200A according to an embodiment.

The light emitting device array 200A according to the embodiment illustrated in FIG. 5 may include a substrate 110 , a plurality of light emitting cells, and a conductive interconnection unit 210 . Although the light emitting device array 200A illustrated in FIG. 5 is illustrated as including only four light emitting cells, the embodiment is not limited thereto. That is, according to another embodiment, the light emitting device array 200A may include fewer or more than four light emitting cells.

The substrate 110 may be made of the same material as the light emitting structure 130 like the substrate 110 shown in FIG. 1 . Like the substrate 110 of the light emitting device 100A illustrated in FIG. 1 , the substrate 110 illustrated in FIG. 5 may include an upper portion 114 and a lower portion 112 .

The non-conductive layer 120 may be disposed in the substrate 110 . 1 , the second thickness T2 of the upper portion 114 and The third thickness T3 of the lower portion 112 may be different or the same.

Since the substrate 110, the non-conductive layer 120, and the first conductivity type intermediate layer 150 are the same as the substrate 110, the non-conductive layer 120A, and the first conductivity type intermediate layer 150 shown in FIG. 1, respectively, A redundant description thereof will be omitted.

The plurality of light emitting cells P1 to P4 may be disposed on the substrate 110 in a horizontal direction. Each of the plurality of light emitting cells P1 to P4 may include a light emitting structure 130 . The light emitting structure 130 of each of the light emitting cells P1 to P4 may include the same material as the substrate 110 .

In addition, similarly to the light emitting structure 130 of the light emitting device 100A shown in FIG. 1 , the light emitting structure 130 shown in FIG. 5 includes the first conductivity-type semiconductor layer 132 and the active layer disposed on the substrate 110 . 134 and a second conductivity type semiconductor layer 136 may be included. Here, the first conductivity type semiconductor layer 132 , the active layer 134 , and the second conductivity type semiconductor layer 136 are the first conductivity type semiconductor layer 132 , the active layer 134 and the second conductivity type shown in FIG. 1 . Since they are the same as those of the semiconductor layer 136 , the same reference numerals are used, and overlapping descriptions are omitted here.

In addition, the first conductivity type semiconductor layer 132 may be implemented as an integral body common to the plurality of light emitting cells P1 to P4 .

In addition, the conductive interconnect 210 serves to electrically connect the two light emitting cells in the plurality of light emitting cells P1 to P4 . That is, the conductive interconnection part 210 may electrically connect the adjacent light emitting cells ((P1 and P2), (P2, P3), or (P3, P4) to each other.

The conductive interconnection unit 210 may connect the plurality of light emitting cells P1 to P4 in series with the first light emitting cell P1 as a starting point and the fourth light emitting cell P4 as an end point.

In addition, each of the plurality of light emitting cells P1 to P4 may include a first electrode 142A and a second electrode 144A. The first electrode 142A may be electrically connected to the first conductivity type semiconductor layer 132 exposed by mesa-etching the second conductivity type semiconductor layer 136 and the active layer 134 . Also, the second electrode 144A may be electrically connected to the second conductivity-type semiconductor layer 136 .

As such, the first and second electrodes 142A and 144A shown in FIG. 5 are the same as the first and second electrodes 142A and 144A shown in FIG. 1, respectively, and thus the same reference numerals are used for them. A duplicate description will be omitted.

6 is a circuit diagram of the light emitting device array 200A shown in FIG. 5 .

Referring to FIG. 6 , the four light emitting cells P1 to P4 may be connected to each other in series. Accordingly, when a positive voltage is applied from the first terminal T1 and a negative voltage is applied to the second terminal T2 , the plurality of light emitting cells P1 to P4 may emit light.

In addition, referring to FIG. 5 , when the depth d of the hole H generated by the mesa etching is greater than 1.5 μm, the movement of carriers to the adjacent light emitting cell may be prevented. Accordingly, the depth d of the hole may be 1.5 μm or more, but the embodiment is not limited thereto. In addition, the thickness D of the light emitting structure 130 may be 1.5d, but the embodiment is not limited thereto.

7 is a cross-sectional view of a light emitting device array 200B according to another embodiment.

The light emitting device array 200B shown in FIG. 7 includes a substrate 110 , a non-conductive layer 120 , a light emitting structure 130 , first and second electrodes 142A and 144A, and a first conductive intermediate layer 150 . and a light extraction structure 160A.

In the case of the light emitting device array 200A shown in FIG. 5 , the light emitted from the active layer 134 passes through the second conductivity-type semiconductor layer 136 and the second electrode 144A in the upper direction (eg, in the y-axis direction). ) can be emitted. On the other hand, in the case of the light emitting device 200B shown in FIG. 7 , the light emitted from the active layer 134 is non-conductive between the first conductivity type semiconductor layer 132 , the first conductivity type intermediate layer 150 , the substrate 110 , and the light emitting device 200B. It may be emitted in an upper direction (eg, a y-axis direction) through the layer 120 .

In this case, the light extraction structure 160A may be further disposed on the light exit surface of the substrate 110 from which the light emitted from the active layer 134 is emitted. When the light extraction structure 160A is disposed, more light from the light exit surface of the substrate 110 may escape from the light emitting device array 200B.

As described above, the light emitting device array 200B shown in FIG. 7 has a shape in which the light emitting device array 200A shown in FIG. 5 is inverted, and unlike the light emitting device array 200A shown in FIG. 5 , the light extraction structure ( 160A) may be further included. Except for this, since the light emitting device array 200B shown in FIG. 7 is the same as the light emitting device array 200A shown in FIG. 5 , overlapping descriptions of the same parts will be omitted.

In addition, in the case of the light emitting device array 200A shown in FIG. 5 , light is emitted through the second conductivity-type semiconductor layer 136 and the second electrode 144A, so these 136 and 144A are made of a material having light transmittance. can be implemented. However, in the case of the light emitting device array 200B shown in FIG. 7 , light is emitted through the first conductivity type semiconductor layer 132 , the first conductivity type intermediate layer 150 , the substrate 110 , and the non-conductive layer 120 . do. Accordingly, these layers 132 , 150 , 110 , and 120 shown in FIG. 7 may be implemented with a light-transmitting material.

In general, a light emitting device or a light emitting device array is driven by a DC voltage. However, when arranging a plurality of light emitting cells like the light emitting device arrays 200A and 200B according to the above-described embodiment, the light emitting device arrays 200A and 200B are provided with the help of a separate voltage converter (or current converter). It can be driven at AC voltage without receiving the voltage. Here, the current conversion device may be a device that converts an AC voltage into a DC voltage. For this reason, the light emitting device arrays 200A and 200B may be suitable for miniaturization, weight reduction, and cost reduction. However, in the case of the light emitting device arrays 200A and 200B driven by the AC voltage, the forward voltage and the reverse voltage are continuously applied. At this time, if the substrate 110 and the light emitting structure 130 are of different types, it is difficult to secure the reliability of the light emitting device array in a high current, high temperature and/or high humidity environment than when the light emitting device arrays 200A and 200B are driven by a DC voltage. It can be difficult. However, since the substrate 110 and the light emitting structure 130 are the same in the light emitting device arrays 200A and 200B according to the embodiment, this reliability problem can be solved.

In addition, the substrate 110 may be required to be non-conductive for the operation of the light emitting device arrays 200A and 200B. However, when the light emitting structure 130 and the substrate 110 are made of the same material in the light emitting device arrays 200A and 200B according to the embodiment, current leakage may occur if the same type of substrate 110 has electrical conductivity. there is a problem with For example, when the light emitting structure 130 and the substrate 110 are made of the same type of GaN, the substrate 110 may have n-type electrical conductivity due to n-type vacancy. Therefore, in order to prevent the substrate 110 from having electrical conductivity, the light emitting devices 100A to 100D and the light emitting device arrays 200A and 200B according to the embodiment are non-conductive layers 120A, 120B, 120), the problem of current leakage can be solved. Accordingly, the light emitting devices 100A to 100D and the light emitting device arrays 200A and 200B according to the embodiment may have excellent thermal conductivity and low electrical conductivity at the same time.

Hereinafter, a method of manufacturing the light emitting device 100A shown in FIG. 1 will be described with reference to the accompanying drawings. The manufacturing methods of the light emitting devices 100B, 100C, and 100D shown in FIGS. 2 to 4 and the light emitting device arrays 200A and 200B shown in FIGS. 5 and 7 are those skilled in the art by modifying the manufacturing method of the light emitting device 100A. Of course, it can be implemented at the level of

8A to 8F are cross-sectional views illustrating a manufacturing method of the light emitting device 100A shown in FIG. 1 according to an embodiment.

Referring to FIG. 8A , a substrate 110 is prepared. The substrate 110 may include at least one of GaN, SiC, ZnO, GaP, InP, Ga ₂ O ₃ , GaAs, and Si. If the substrate 110 and the light emitting structure 130 to be described later can be made of the same material, the embodiment is not limited to the type of the substrate 110 .

Thereafter, referring to FIG. 8B , ions are implanted 122 into the substrate 110 to form the non-conductive layer 120A inside the substrate 110 . Here, the ions for forming the non-conductive layer 120A may include at least one of Mg, Zn, C, and oxygen ions.

In addition, ions may be implanted so that the minimum value of the first thickness T1 of the non-conductive layer 120A is 10 nm. In addition, ions may be implanted so that the non-conductive layer 120A is positioned above, below, or in the middle of the substrate 110 .

If ions are implanted into the entire surface of the substrate 110 , crystallinity may deteriorate. To prevent this, ions may be implanted into the back surface of the substrate 110 as illustrated in FIG. 8B .

Thereafter, referring to FIG. 8C , the first conductivity-type intermediate layer 150 is formed on the substrate 110 . The first conductivity-type intermediate layer 150 may be an n-type GaN layer. In some cases, the formation of the first conductivity-type intermediate layer 150 may be omitted.

Thereafter, referring to FIG. 8D , the light emitting structure 130 is formed on the first conductivity-type intermediate layer 150 . When the first conductivity-type intermediate layer 150 is formed on the substrate 110 , the light emitting structure 130 may be formed more stably. The light emitting structure 130 may be formed by sequentially stacking the first conductivity type semiconductor layer 132 , the active layer 134 , and the second conductivity type semiconductor layer 136 on the first conductivity type intermediate layer 150 .

First, the first conductivity type semiconductor layer 132 is formed on the first conductivity type intermediate layer 150 . The first conductivity type semiconductor layer 132 may be formed of a compound semiconductor of group III-V or group II-VI doped with a first conductivity type dopant, and may be doped with a first conductivity type dopant. When the first conductivity-type semiconductor layer 132 is an n-type semiconductor layer, the first conductivity-type dopant is an n-type dopant and may include Si, Ge, Sn, Se, and Te, but is not limited thereto.

For example, the first conductivity type semiconductor layer 132 has a composition formula of Al _x In _y Ga _(1-xy) N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) It may be formed using a semiconductor material. The first conductivity type semiconductor layer 132 may be formed of at least one of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP.

An active layer 134 is formed on the first conductivity-type semiconductor layer 132 . The active layer 134 may include at least one of a single well structure, a multi-well structure, a single quantum well structure, a multi quantum well (MQW) structure, a quantum-wire structure, or a quantum dot structure. can be formed into one.

The well layer/barrier layer of the active layer 134 may have a pair structure of any one or more of InGaN/GaN, InGaN/InGaN, GaN/AlGaN, InAlGaN/GaN, GaAs (InGaAs)/AlGaAs, and GaP (InGaP)/AlGaP. However, the present invention is not limited thereto. The well layer may be formed of a material having a bandgap energy lower than the bandgap energy of the barrier layer.

A conductive cladding layer (not shown) may be formed on and/or below the active layer 134 . The conductive cladding layer may be formed of a semiconductor having a higher bandgap energy than that of the barrier layer of the active layer 134 . For example, the conductive clad layer may include GaN, AlGaN, InAlGaN, or a superlattice structure. In addition, the conductivity-type cladding layer may be doped with n-type or p-type.

A second conductivity type semiconductor layer 136 is formed on the active layer 134 . The second conductivity type semiconductor layer 136 may be formed of a semiconductor compound. It may be implemented as a compound semiconductor of group III-V or group II-VI. For example, the second conductivity type semiconductor layer 136 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) may include The second conductivity type semiconductor layer 136 may be doped with a second conductivity type dopant. When the second conductivity-type semiconductor layer 136 is a p-type semiconductor layer, the second conductivity-type dopant is a p-type dopant and may include Mg, Zn, Ca, Sr, Ba, or the like.

Thereafter, referring to FIG. 8E , the second conductivity type semiconductor layer 136 and the active layer 134 , and a portion of the first conductivity type semiconductor layer 132 are mesa-etched to expose the first conductivity type semiconductor layer 132 . .

Thereafter, referring to FIG. 8F , a first electrode 142A is formed on the exposed first conductivity-type semiconductor layer 132 , and a second electrode 144A is formed on the second conductivity-type semiconductor layer 136 . . Each of the first and second electrodes 142A and 144A includes, for example, at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (Au). It can be formed into a single-layer or multi-layer structure using

Hereinafter, a light emitting device package according to an embodiment including the light emitting device 100A shown in FIG. 1 will be described with reference to the accompanying drawings. In addition, the light emitting devices 100B, 100C, and 100D shown in FIGS. 2 to 4 or the light emitting device arrays 200A and 200B shown in FIGS. 5 and 7 may be implemented in a package form as shown in FIG. 9 . there is.

9 is a cross-sectional view of the light emitting device package 300 according to the embodiment.

The light emitting device package 300 shown in FIG. 9 includes a package body 310 , first and second lead frames 322 and 324 , first and second wires 342 and 344 , and a molding member 330 . can do.

The package body 310 may include silicon, synthetic resin, or metal, and an inclined surface may be formed around the light emitting device 100A.

The first and second lead frames 322 and 324 are electrically isolated from each other, and serve to provide power to the light emitting device 100A. In addition, the first and second lead frames 322 and 324 may serve to increase light efficiency by reflecting the light generated from the light emitting device 100A, and heat generated from the light emitting device 100A to the outside. It can also serve as an exhaust.

In the case of FIG. 9 , the light emitting device 100A is illustrated as being mounted on the second lead frame 324 , but the embodiment is not limited thereto. That is, according to another embodiment, the light emitting device 100A may be disposed on the first lead frame 322 or on the package body 310 .

The light emitting device 100A may be electrically connected to the first and second lead frames 322 and 324 by any one of a wire method, a flip chip method, or a die bonding method. For example, as illustrated in FIG. 9 , the light emitting device 100A is electrically connected through a first lead frame 322 and a first wire 342 and a second lead frame 324 and a second wire ( 344) may be electrically connected.

The molding member 330 may surround and protect the light emitting device 100A. Also, the molding member 330 may include a phosphor to change the wavelength of light emitted from the light emitting device 100A.

A plurality of light emitting device packages according to the embodiment may be arranged on a substrate, and optical members such as a light guide plate, a prism sheet, a diffusion sheet, etc. may be disposed on a light path of the light emitting device package. Such a light emitting device package, a substrate, and an optical member may function as a backlight unit.

In addition, it may be implemented as a display device, an indicator device, and a lighting device including the light emitting device package according to the embodiment.

Here, the display device includes a bottom cover, a reflecting plate disposed on the bottom cover, a light emitting module emitting light, a light guide plate disposed in front of the reflecting plate and guiding light emitted from the light emitting module in front of the light guide plate An optical sheet comprising prism sheets disposed thereon, a display panel disposed in front of the optical sheet, an image signal output circuit connected to the display panel and supplying an image signal to the display panel, and a color filter disposed in front of the display panel may include Here, the bottom cover, the reflector, the light emitting module, the light guide plate, and the optical sheet may form a backlight unit.

In addition, the lighting device includes a light source module including a substrate and a light emitting device package according to an embodiment, a heat sink for dissipating heat of the light source module, and a power supply unit that processes or converts an electrical signal received from the outside and provides the light source module to the light source module may include For example, the lighting device may include a lamp, a head lamp, or a street lamp.

The head lamp includes a light emitting module including light emitting device packages disposed on a substrate, a reflector that reflects light emitted from the light emitting module in a predetermined direction, for example, forward, and a lens that refracts light reflected by the reflector forward. , and a shade that blocks or reflects a portion of light reflected by the reflector and directed to the lens to form a light distribution pattern desired by the designer.

In the above, the embodiment has been mainly described, but this is only an example and does not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are not exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

100A, 100B, 100C, 100D: light emitting element 110: substrate
112: lower part 114: upper part
120, 120A, 120B: non-conductive layer 130: light emitting structure
132: first conductivity type semiconductor layer 134: active layer
136: second conductivity type semiconductor layer 142A, 142B: first electrode
144A, 144B: second electrode 150: first conductive type intermediate layer
160A, 160B: light extraction structure 200A, 200B: light-emitting element array
210: conductive interconnect 300: light emitting device package
310: package body 322: first lead frame
324: second lead frame 342: first wire
344: second wire 330: molding member

Claims (17)

Board;
a non-conductive layer disposed within the substrate;
a light emitting structure made of the same material as the substrate and including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer disposed on the substrate; and
a first conductive intermediate layer disposed between the light emitting structure and the substrate;
The substrate is
an upper portion disposed between the non-conductive layer and the light emitting structure; and
a lower portion disposed under the non-conductive layer;
The upper part and the lower part are light emitting devices made of the same material. According to claim 1, wherein the non-conductive layer comprises an ion implantation layer,
The ion implantation layer includes at least one of Mg, Zn, C or oxygen ions,
The minimum value of the thickness of the non-conductive layer is 10 nm,
The substrate is a polar, semi-polar or non-polar light emitting device. delete delete delete delete According to claim 1,
The thickness of the upper portion is smaller than the thickness of the lower portion of the light emitting device. delete delete delete delete delete The method of claim 7, wherein the non-conductive layer is disposed to be spaced apart from each other in a direction perpendicular to the thickness direction of the light emitting structure,
The non-conductive layer is a light emitting device including a through hole connecting the upper portion and the lower portion. delete Board;
a non-conductive layer disposed within the substrate;
a plurality of light emitting cells arranged in a horizontal direction on the substrate; and
a conductive interconnect for electrically connecting two light emitting cells among the plurality of light emitting cells;
Each of the light emitting cells is
a light emitting structure made of the same material as the substrate and including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer disposed on the substrate;
a first conductivity-type intermediate layer disposed between the light emitting structure and the substrate;
a first electrode connected to the first conductivity type semiconductor layer exposed by mesa-etching the second conductivity type semiconductor layer and the active layer; and
a second electrode connected to the second conductivity type semiconductor layer;
The first conductivity type semiconductor layer of the plurality of light emitting cells is integral,
The substrate is
an upper portion disposed between the non-conductive layer and the light emitting structure; and
a lower portion disposed under the non-conductive layer;
The upper portion and the lower portion are light emitting device arrays made of the same material. delete delete

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