JP2001313420A - Iii nitride-based compound semiconductor light-emitting element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting element, in which the light emitted from the side face of a semiconductor layer can be used effectively. SOLUTION: A semiconductor laminate which contains a light emitting layer is etched, its side face (a rise face) is exposed, and a reflection face which counterpoises the side face is formed inside the same chip.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a group III nitride compound semiconductor light emitting device.

[0002]

2. Description of the Related Art A light emitting device is disclosed in Japanese Patent Application Laid-Open No. 11-273571.
As shown in Japanese Patent Application Laid-Open Publication No. H11-260, the mounting lead is mounted in a cup portion of a mounting lead. A conductive wire is connected to the light-emitting element, and the light-emitting element is sealed with a shell-shaped sealing member made of a light-transmitting resin. The light emitting device thus configured has an optical axis in the central axis direction (normal direction) of the light emitting element chip,
The light emitted from the light emitting element is condensed in the optical axis direction by the tip hemisphere (convex lens) of the shell type sealing member. However, since the light deviating from the tip hemisphere cannot be controlled, in order to effectively use the light in the lateral direction (the direction away from the central axis direction) of the light emitting element chip, the peripheral wall of the cup portion is formed in a parabolic shape so that the lateral direction of the peripheral wall is Is reflected in the optical axis direction.

[0003]

A group III nitride compound semiconductor light-emitting device that emits blue-green light emits more light in the lateral direction than a red light-emitting device. In a group III nitride compound semiconductor light emitting device that emits a large amount of light in the lateral direction, how to use the light in the lateral direction is a serious problem in improving the luminous efficiency of the light emitting device. Looking at the reflection surface of the peripheral wall of the conventional cup from this point of view, in a normal design, a space between the chip and the peripheral wall of the cup is provided as a space for releasing a jig holding the chip.
A clearance of 00 to 300 μm is required. On the other hand, the thickness of the semiconductor layer in the chip is several μm, and the height of the cup is also limited by the design of the light emitting device. Therefore, of the light emitted in the horizontal direction, only the light falling within a range of an elevation angle of about 10 degrees from the direction perpendicular to the central axis (direct side direction) could be reflected by the peripheral wall reflecting surface of the cup.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a light emitting device capable of effectively utilizing light emitted from a side surface of a semiconductor layer. A device is proposed. A group III nitride-based compound, wherein a semiconductor laminated portion including a light-emitting layer and a reflection surface disposed opposite to a side surface formed by etching the semiconductor laminated portion are provided in the same chip, Semiconductor light emitting device.

According to the group III nitride compound semiconductor light emitting device having such a configuration, since the reflection layer is formed in the same chip as the semiconductor laminated portion, the interval between the two can be reduced as much as possible. it can. Thereby, more of the light emitted in the lateral direction from the semiconductor laminated portion can be captured by the reflective layer and reflected in the central axis (optical axis) direction. Therefore, light use efficiency is improved. Therefore, a light-emitting element that achieves high luminance with low power can be obtained.

Since the group III nitride compound semiconductor light emitting device uses an insulating sapphire substrate, a part of the p-type semiconductor layer, the light-emitting layer and the n-type semiconductor layer is removed by etching in order to form electrodes. By using this etching step, a semiconductor laminated portion including a light emitting layer can be formed without adding a special step. In this case, the side surface (standing surface) of the semiconductor laminated portion is formed by etching. Any shape (width) by etching
Since the n-type semiconductor layer can be exposed to the surface, if a reflective surface is formed by selecting an appropriate formation method there, the reflective surface can be formed as close as possible to the side surface of the semiconductor laminated portion. . For example, if the material for forming the reflective surface is the same as that of the n-type pedestal electrode, the reflective surface can also be formed by vapor deposition when depositing the n-type pedestal electrode. do not do. That is, only by appropriately changing the mask used in the etching step and the evaporation step of the n-type pedestal electrode, without making any essential changes to the conventional steps,
The light emitting device of the present invention can be manufactured. That is, a high-power light-emitting element can be provided at low cost.

Next, the elements of the present invention will be described in detail. The semiconductor laminated portion is formed by laminating a plurality of group III nitride compound semiconductor layers, and includes a light emitting layer therein. In this specification, _Al Group III nitride compound semiconductor as a general formula _{X Ga Y In 1-X-} Y N (0 ≦ X ≦ 1,0 ≦ Y
≦ 1, 0 ≦ X + Y ≦ 1), a so-called binary system of AlN, GaN and InN, Al _x Ga _1-x N, Al _x
In _1-x N and Ga _x In _1-x N (in the above, 0
<X <1). Some of the group III elements may be replaced with boron (B), thallium (Tl), etc., and some of nitrogen (N) may be replaced with phosphorus (P), arsenic (A
s), antimony (Sb), bismuth (Bi) and the like. The group III nitride compound semiconductor layer may contain any dopant. As an n-type impurity, S
i, Ge, Se, Te, C, etc. can be used. p
Mg, Zn, Be, Ca, Sr, Ba as type impurities
Etc. can be used. After doping with a p-type impurity, the group III nitride compound semiconductor can be exposed to electron beam irradiation, plasma irradiation, or heating by a furnace. The method of forming the group III nitride-based compound semiconductor layer is not particularly limited. In addition to metal organic chemical vapor deposition (MOCVD), well-known molecular beam crystal growth (MBE) and halide vapor deposition (HVPE) ), A sputtering method, an ion plating method, an electron shower method, or the like. Note that as a structure of the light emitting element, a homo structure, a hetero structure, or a double hetero structure having a MIS junction, a PIN junction, or a pn junction can be used. ). A quantum well structure (single quantum well structure or multiple quantum well structure) can be adopted as the light emitting layer.

A stacked body of a plurality of group III nitride compound semiconductor layers is etched to expose an n-type pedestal electrode forming surface. Using this etching process, the chip is etched continuously or discontinuously over the entire circumference to form side surfaces (standing surfaces). The etching step for forming the side surface and the etching step for forming the n-type pedestal electrode forming surface may be separate steps. When both processes are performed separately, the etching depth for forming the side surface (first
Is preferably larger than the etching depth (second depth) for forming the n-type pedestal electrode. Thus, since the lower edge of the reflection surface is disposed lower than the semiconductor lamination portion, the light emitted downward from the side surface can be supplemented by the reflection surface. If this etching depth is shallow,
Of the light emitted from the side surface of the semiconductor laminated portion, a component going downward enters the semiconductor layer (n-type semiconductor layer). Since this semiconductor layer is also formed of a group III nitride-based compound semiconductor and has a band gap energy corresponding to the emission wavelength, most of the incident light is absorbed by the semiconductor material. Therefore, it is preferable that the light emitted from the side surface of the semiconductor laminated portion be directly incident on the reflection layer as much as possible and reflected in the optical axis direction. Such etching is performed by dry etching using a gas such as argon or chlorine.

It is desirable that the translucent metal electrode formed on the p-type semiconductor is formed over the entire area of the p-type semiconductor. III
In a group nitride-based compound semiconductor, the electric resistance of the p-type semiconductor layer is generally high, so that a current is uniformly injected into the light emitting layer to obtain sufficient light emission. By forming the translucent electrode up to the edge portion of the p-type contact layer, the effective light emitting portion reaches the side surface of the semiconductor laminated portion. As a result, strong light emission from the side is obtained. As the translucent electrode, for example, an alloy containing cobalt and gold can be used. Part of cobalt is nickel (Ni), iron (Fe), copper (Cu), chromium
(Cr), tantalum (Ta), vanadium (V), manganese (Mn),
Aluminum (Al), replaced with at least one element of silver (Ag), a part of gold palladium (Pd), iridium (I
r) and at least one element of platinum (Pt). The translucent electrode is formed by laminating cobalt with a thickness of 0.5 to 15 nm as a first electrode layer on a p-type contact layer, and then with gold of 3.5 to 25 nm as a second electrode layer on the cobalt layer. Are laminated with a film thickness of Then, both are alloyed by heat treatment. After the heat treatment, the element distribution in the depth direction from the surface of the p-type contact layer is Au more than Co.
Is deeply penetrated. Here, the heat treatment is preferably performed in a gas containing oxygen. At this time, the gas containing oxygen includes O ₂ , O ₃ , CO, CO ₂ , NO, N ₂ O, N
At least one kind of O ₂ or H ₂ O or a mixed gas thereof can be used. Or O ₂ , O ₃ , CO, CO ₂ , NO, N
A mixed gas of at least one of ₂ O, NO ₂ or H ₂ O and an inert gas, or O ₂ , O ₃ , CO, CO ₂ , NO, N ₂ O, NO ₂ , or H ₂ A mixed gas of a mixed gas of O and an inert gas can be used. In short, a gas containing oxygen is an oxygen atom,
It means a gas of a molecule having an oxygen atom. The pressure of the atmosphere during the heat treatment may be at least the pressure at which the gallium nitride-based compound semiconductor does not thermally decompose at the heat treatment temperature. The gas containing oxygen may be introduced at a pressure higher than the decomposition pressure of the gallium nitride-based compound semiconductor when only O ₂ gas is used, and when used in a state mixed with another inert gas, It suffices that all gases have a pressure equal to or higher than the decomposition pressure of the gallium nitride-based compound semiconductor, and that the O ₂ gas has a ratio of about 10 ⁻⁶ or more to all gases. In short, it is sufficient that a very small amount of gas containing oxygen exists. It should be noted that the upper limit of the amount of the gas containing oxygen is not particularly limited from the characteristics of p-type resistance reduction and electrode alloying. In short, it can be used to the extent that it can be manufactured. Regarding the heat treatment, the temperature is most desirably 500 to 600 ° C. 500
At a temperature of not less than ° C., a low-resistance p-type gallium nitride-based compound semiconductor whose resistivity is completely saturated can be obtained. or,
At a temperature of 600 ° C. or lower, the alloying treatment of the electrode can be favorably performed. A desirable temperature range is 450
６650 ° C. For details, refer to Japanese Patent Application No. 2000-92611.
No. (Applicant Reference Number 990472, Agent Reference Number: P0197)
Please refer to.

The present invention is also applied to a case where an electrode formed on a p-type semiconductor is not translucent. When the electric resistance of the p-type semiconductor is reduced and an electrode is formed in a spot on the p-type semiconductor, the entire pn junction surface becomes a light emitting region as in the case of conventional GaAs or the like. This is because they are emitted from the side.

It is preferable that the reflection layer is disposed close to the side surface of the semiconductor laminated portion so that more of the light emitted from the side surface can be reflected. The thickness of the reflective layer is preferably thick. According to the study of the present inventor, the distance between the reflective layer and the side surface is preferably 0.1 to 10 μm. If the length is shorter than the lower limit, the reflective layer may contact the side surface and block it, depending on the accuracy of the manufacturing process. If the value is larger than the upper limit, the area of the etching region that does not operate effectively as a light emitting element becomes unnecessarily large. The more preferable distance between the reflective layer and the side surface of the semiconductor laminated portion is 0.2
７7 μm, and a still more preferable distance is 0.3 to 5 μm.
m, and the most preferable distance is 0.5 to 4 μm.
The preferred range of the thickness of the reflective layer is 0.5 to 30 μm. If the thickness is smaller than the lower limit, light emitted from the side surface cannot be effectively reflected. If the thickness is larger than the upper limit, it takes time to manufacture, and the reflective surface may be crushed in a later step. The film thickness of the reflective layer is more preferably 0.7 to 15 μm, and still more preferably 1.0 to 15 μm.
10 μm, most preferably 1.5 to 5 μm.

In order to effectively use the light emitted from the side surface of the semiconductor laminated portion, it is preferable that the reflecting surface reflects the light in the direction of the optical axis (the direction of the central axis of the chip). Of course, the direction of reflection is not limited to this as long as the required optical characteristics are satisfied. The reflecting surface may be formed to be substantially a mirror surface facing the side surface of the semiconductor laminated portion, and the forming method is not particularly limited. For example, when a reflective member having a reflective surface is formed by vapor deposition when depositing an n-type pedestal electrode, a substantial mirror surface can be obtained, so that an unnecessary increase in man-hours can be suppressed.

If attention is paid to the n-type pedestal electrode formed of the same material at the same time as the reflection surface, there is also a surface facing the side surface of the semiconductor laminated portion. Therefore, it is possible to form the surface of the n-type pedestal electrode facing the semiconductor laminated portion on the reflection surface (second reflection surface) and reflect the light emitted from the side surface on the reflection surface for effective use. preferable. The distance between the semiconductor laminated portion and the reflection surface of the n-type pedestal electrode is 0.1 to 10
It is preferably set to μm. The lower limit of the above range is defined for the purpose of preventing a short circuit from occurring between the translucent electrode or the p-type semiconductor layer and the n-type pedestal electrode. The upper limit of the above range is for not unnecessarily increasing a region that does not contribute to light emission. The more preferable value of the distance between the semiconductor laminated portion and the n-type pedestal electrode is 0.2 to 7 μm, the more preferable value is 0.3 to 5 μm, and the most preferable value is 0.5 to 4 μm.
μm.

Since the reflecting surface of the present invention can reflect more lateral light than the reflecting surface of the peripheral wall of the cup portion, the mounting of the light emitting element of the present invention is the same as that of the conventional one. The luminous intensity can be increased by about 10% with respect to the injected power. When the light emitting device of the present invention is used, the peripheral wall reflecting surface of the cup portion may not be required. In this case, it is not necessary to form the cup portion on the mount lead. Therefore, the structure of the mount lead is simplified, and its manufacture at low cost is possible, and the manufacturing cost of the light emitting device itself is reduced. The light emitting device of the present invention is particularly effective in an SMD type LED (a type in which a chip is directly mounted on a printed circuit board) because a reflective layer is formed therein.

[0015]

Embodiments of the present invention will be described below.
The embodiment is a light emitting diode, and FIG. 1 shows the structure of a group III nitride compound semiconductor layer.

Layer: Composition: Dopant (thickness) Translucent electrode 16: Au (6 nm) / Co (1.5 nm) P-type clad layer 15: p-GaN: Mg (0.3 μm) Light-emitting layer 14: Superlattice structure Quantum well layer: In _0.15 Ga _0.85 N (3.5 nm) Barrier layer: GaN (3.5 nm) Number of repetition of quantum well layer and barrier layer: 1 to 10 n-type cladding layer 13: n-GaN: Si ( 4 μm) AlN buffer layer 12: AlN (60 nm) Substrate 11: sapphire (a-plane) (300 μm)

The n-type cladding layer 13 can have a two-layer structure including a low electron concentration n− layer on the light emitting layer 14 side and a high electron concentration n + layer on the buffer layer 12 side. The latter is called an n-type contact layer. The light emitting layer 14 is not limited to the super lattice structure. As a structure of the light emitting element, a single hetero type, a double hetero type, a homo junction type, or the like can be used. A wide band gap group III nitride compound semiconductor layer doped with an acceptor such as magnesium may be interposed between the light emitting layer 14 and the p-type cladding layer 15. This is to prevent the electrons injected into the light emitting layer 14 from diffusing into the p-type cladding layer 15. The p-type cladding layer 15 may have a two-layer structure including a low hole concentration p− layer on the light emitting layer 14 side and a high hole concentration p + layer on the electrode side. The latter is called a p-type contact layer. In the light emitting diode having the above structure, each group III nitride compound semiconductor layer is formed by performing MOCVD under general conditions.

Next, a mask is formed and the p-type cladding layer 1 is formed.
5. The active layer 14 and a part of the n-type cladding layer 13 are removed by reactive ion etching to expose the n-type pedestal electrode forming surface 21 on which the n-type pedestal electrode 18 is to be formed (see FIG. 1). At the same time as the n-type pedestal electrode forming surface 21, the entire surface of the light emitting surface facing the optical axis direction is etched to form the reflecting member forming surface 23. The semiconductor lamination portion 20 is defined by this etching.

A Co (cobalt) layer (1.5 nm) and an Au (gold) layer (6 nm) are sequentially stacked on the entire surface of the wafer by a vapor deposition apparatus. Next, a photoresist is uniformly applied, and the n-type pedestal electrode forming surface 2 is formed by photolithography.
The photoresist is removed at a portion (clearance region 25) having a width of about 10 μm from 1 and its surroundings, and the light-transmissive electrode forming material at that portion is removed by etching to expose the semiconductor layer. After that, the photoresist is removed.
Insulating and transparent protective film (silicon oxide, silicon nitride, titanium oxide, aluminum oxide, etc.) from the clearance region 25 to the periphery of the n-type pedestal electrode forming surface 21.
Can also be coated. As a forming method, a sputtering method or a CVD method can be adopted. Next, by the lift-off method,
V (vanadium) layer (17.5 nm), Au layer (1.5
μm) and an Al (aluminum) layer (10 nm) are sequentially deposited and laminated to form a p-type pedestal electrode 19.

The n-type pedestal electrode 18 made of V and Al is similarly formed by a lift-off method. When depositing the V / Al alloy, the wafer plane is inclined with respect to the evaporation source (material source) and rotated (when the sputtering method is employed, the wafer plane is inclined with respect to the sputtering source and is rotated). As a result, the peripheral surface of the V / Al alloy at the opening of the photoresist 40 becomes tapered as shown in FIG. The tapered side surface is used as the reflection layer 31 of the reflection member 30 and the second reflection surface 33 of the n-type pedestal electrode 18. By changing the inclination angle of the wafer plane with respect to the evaporation source (in some cases, gradually changing the inclination angle during vapor deposition), the inclination of the taper can be arbitrarily adjusted. Thereby, the angle of reflection of light by the reflection surface can be controlled. In this embodiment, an evaporation apparatus provided with a planetary type wafer substrate holder is used.

The wafer thus obtained is placed in a heating furnace, the inside of the furnace is evacuated to 1 Pa or less, and then O ₂ is supplied to 10 Pa or more. Then, in this state, the temperature of the furnace is set to 550 ° C., and the heat treatment is performed for about 4 minutes. Thereby, the translucent electrode 16 and the p-type pedestal electrode 17 are alloyed,
The alloying of the n-type pedestal electrode 18 of V and Al and the ohmic junction of these with the p-type semiconductor and the n-type semiconductor are formed.
Thereafter, the wafer is cut into chips by a conventional method.

The light emitting device 1 of the embodiment thus configured
According to the method, as shown in FIG. 4A, the reflection surface 31 is arranged near the side surface of the semiconductor laminated portion 20 so as to be opposed to each other.
Of the light emitted from the light emitting layer 14 in the lateral direction, a component falling within the angle α is captured by the reflecting surface 31 and can be reflected in a desired direction. On the other hand, since the light emitting element 50 of the conventional example is not provided with such a reflection surface, light emitted in the lateral direction from the light emitting layer 54 is reflected by the peripheral wall 55 of the cup portion. Since there is a large gap between the outer peripheral wall 55 and the peripheral wall 55, the light reflected in the cup peripheral wall 55 in the laterally emitted light is a component falling within an extremely small angle β (<< α).

FIG. 5 shows a light emitting device 60 according to another embodiment.
The same elements as those of the light emitting element of the previous embodiment are denoted by the same reference numerals, and the description will not be repeated. In the light emitting device 60 of this embodiment, the reflection member 61 is separated from the n-type pedestal electrode 18. Further, the groove 63 is formed by etching to expose the side surface of the semiconductor laminated portion 20. The groove 63 is preferably formed in the same step as the n-type pedestal electrode forming surface 21. The side surface of the reflecting member 61 facing the side surface of the semiconductor laminated portion 20 is formed on the reflecting surface 65. The reflection member 6
Since a part of 1 is mounted on the p-type semiconductor layer, it is formed higher than the reflecting member of the previous embodiment. Thereby, more of the light emitted from the side surface of the semiconductor stacked unit 20 can be reflected by the reflection surface 65.

This reflecting member 61 is also formed by the lift-off method using the same material in the same process as the n-type pedestal electrode 18 in the same manner as the reflecting member 30 of the previous embodiment. Since the reflection member 61 thus obtained has conductivity, the underlying n-type semiconductor layer has the same potential. That is, in this embodiment, each side of the effective light emitting region defined by the translucent electrode 16 has the same potential on the n-type side as far as it is. Thereby, the current density injected into the light emitting layer 14 is made uniform, and the conductive reflecting member (n-type auxiliary electrode) is used.
High uniform light emission can be achieved as compared with those having no light emission.

The present invention is not at all limited to the description of the above-described embodiments and examples. Various modifications are included in the present invention without departing from the scope of the claims and within the scope of those skilled in the art.

Hereinafter, the following items will be disclosed. 11 A reflective surface provided on the group III nitride compound semiconductor light emitting device, which is provided in the same chip as the semiconductor laminated portion including the light emitting layer and faces a side surface formed by etching the semiconductor laminated portion. Reflective surface to be placed. 12. The reflection surface reflects light from a side surface of the semiconductor laminated portion in an optical axis direction of a light emitting element.
2. The reflecting surface according to 1. 13. The distance between the reflecting surface and the side surface of the semiconductor laminated portion is 0.1 to 10 μm, wherein 11 or 1
3. The reflecting surface according to 2. 14. The reflection surface according to any one of items 11 to 13, wherein the reflection surface is formed of the same material as the n-type pedestal electrode. 15. The reflection surface according to claim 14, wherein a portion of the n-type pedestal electrode facing a side surface of the semiconductor laminated portion forms a second reflection surface. 16. The reflection surface is formed on an n-type semiconductor layer formed by etching to a first depth, and the n-type semiconductor formed by etching to a second depth shallower than the first depth. The reflection surface according to claim 14 or 15, wherein the n-type pedestal electrode is formed on a layer. 17. The reflection surface according to any one of 14 to 16, wherein the reflection surface is formed integrally with the n-type pedestal electrode. 21. An n-type pedestal electrode having a reflection surface at a portion opposed to a side surface formed by etching the semiconductor layer laminated portion including the light emitting layer, and light emitted from the side surface is emitted from a light emitting element by the reflection surface. A group III nitride compound semiconductor light-emitting device, which is reflected in an axial direction. 22 An n-type pedestal electrode of a group III nitride compound semiconductor light emitting device, a portion facing a side surface formed by etching of a semiconductor layer laminated portion including a light emitting layer is a reflection surface, and is emitted from the side surface. An n-type pedestal electrode, wherein light is reflected by the reflection surface in an optical axis direction of the light emitting element. 31. A group III nitride-based compound semiconductor light emitting device, wherein a semiconductor laminated portion including a light emitting layer and a reflection surface disposed opposite to a rising surface of the semiconductor laminated portion are provided in the same chip. . 32 The reflection surface reflects light from the side surface of the semiconductor laminated portion in the optical axis direction of the light emitting element.
2. The group III nitride compound semiconductor light emitting device according to item 1. 33, wherein the distance between the reflection surface and the side surface of the semiconductor laminated portion is 0.1 to 10 μm.
3. The group III nitride compound semiconductor light emitting device according to item 2. 34. The group III nitride compound semiconductor light emitting device according to any one of 31 to 33, wherein the reflection surface is formed of the same material as the n-type pedestal electrode. 35. The group III nitride compound semiconductor light-emitting device according to claim 34, wherein a portion of the n-type pedestal electrode facing a side surface of the semiconductor lamination portion forms a second reflection surface. 36. The reflecting surface is formed on an n-type semiconductor layer formed by etching to a first depth, and the n-type semiconductor formed by etching to a second depth shallower than the first depth. 36. The group III nitride compound semiconductor light emitting device according to claim 34 or 35, wherein the n-type pedestal electrode is formed on the layer. 37. The group III nitride-based compound semiconductor light emitting device according to any one of claims 34 to 36, wherein the reflection surface is formed integrally with the n-type pedestal electrode. 41, an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer are stacked on a substrate to form a laminate, and the laminate is etched to expose the n-type semiconductor layer to be a reflective member forming surface, A method for manufacturing a group III nitride compound semiconductor light emitting device, comprising: forming a reflecting member having a surface facing a side surface formed by the etching of the laminate as a reflecting surface on the reflecting member forming surface. 42. The III according to 41, wherein an n-type pedestal electrode forming surface is also formed in the etching step.
A method of manufacturing a group III nitride compound semiconductor light emitting device. 43. The III according to 42, wherein the reflecting member and the n-type pedestal electrode are formed simultaneously and with the same material.
A method of manufacturing a group III nitride compound semiconductor light emitting device. 44. The manufacturing method according to any one of 41 to 43, wherein the reflecting member is formed by depositing the wafer while rotating the wafer while tilting the wafer with respect to the material source. 51 A group III nitride-based compound semiconductor light emitting device, wherein an n-type pedestal electrode and an n-type auxiliary electrode separated from the n-type pedestal electrode are provided on an n-type semiconductor layer. 52. The group III nitride compound semiconductor light emitting device according to item 51, wherein the n-type auxiliary electrode is arranged so as to surround a semiconductor laminated portion including a light emitting layer. 53 The n-type auxiliary electrode according to 51 or 52, wherein the n-type auxiliary electrode is separated at a corner of the semiconductor laminated portion.
Group III nitride compound semiconductor light emitting device.

In the above description, the group III nitride compound semiconductor light emitting device has been described as an example. However, from the viewpoint of effectively utilizing the light emitted from the side surface of the light emitting device chip, the material of the semiconductor is as follows. It is not limited to group III nitride compounds. Therefore, the following matters are disclosed. 61 A semiconductor light emitting device, wherein a semiconductor laminated portion including a light emitting layer and a reflection surface arranged to face a side surface formed by etching the semiconductor laminated portion are provided in the same chip. 62 The reflection surface reflects light from the side surface of the semiconductor laminated portion in the optical axis direction of the light emitting element.
2. The semiconductor light emitting device according to 1. 63, wherein the distance between the reflection surface and the side surface of the semiconductor laminated portion is 0.1 to 10 μm.
3. The semiconductor light emitting device according to 2. 64. The semiconductor light emitting device according to any one of 61 to 63, wherein the reflection surface is formed of the same material as the n-type pedestal electrode. 65. The semiconductor light emitting device according to 64, wherein a portion of the n-type pedestal electrode facing a side surface of the semiconductor laminated portion forms a second reflection surface. 66, the reflective surface is formed on an n-type semiconductor layer formed by etching to a first depth, and the n-type semiconductor formed by etching to a second depth shallower than the first depth. 66. The semiconductor light emitting device according to 64 or 65, wherein the n-type pedestal electrode is formed on a layer. 67. The semiconductor light emitting device according to any one of 64 to 66, wherein the reflection surface is formed integrally with the n-type pedestal electrode.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a group III nitride compound semiconductor layer of a light emitting device according to an embodiment of the present invention.

FIGS. 1A and 1B show a light-emitting element of an example, FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view taken along line AA in FIG.

FIG. 3 is a sectional view showing a method of forming a reflection member.

FIGS. 4A and 4B show a relationship between a semiconductor laminated portion and a reflective surface in a light emitting element, FIG. 4A shows a relationship between a semiconductor laminated portion and a reflective surface in an embodiment of the present invention, and FIG. 5 shows the relationship between the light emitting element and the peripheral wall of the cup part.

5A and 5B show a light emitting device according to another embodiment of the present invention, wherein FIG. 5A is a plan view, and FIG. 5B is a sectional view taken along line BB in FIG.

[Explanation of symbols]

 1, 50, 60 Light-emitting element 14 Light-emitting layer 18 n-type pedestal electrode 20 Semiconductor laminated portion 30, 61 Reflecting member 31, 33, 65 Reflecting surface

Claims (7)

[Claims] 1. A semiconductor chip comprising: a semiconductor laminated portion including a light emitting layer; and a reflection surface disposed to face a side surface formed by etching the semiconductor laminated portion, in the same chip. Group III compound semiconductor light emitting device. 2. The group III nitride compound semiconductor light emitting device according to claim 1, wherein the reflection surface reflects light from a side surface of the semiconductor laminated portion in an optical axis direction of the light emitting device. 3. The group III nitride compound semiconductor light-emitting device according to claim 1, wherein a distance between the reflection surface and a side surface of the semiconductor laminated portion is 0.1 to 10 μm. 4. The group III nitride compound semiconductor light emitting device according to claim 1, wherein said reflection surface is formed of the same material as the n-type pedestal electrode. 5. The group III nitride compound semiconductor light emission according to claim 4, wherein a portion of said n-type pedestal electrode facing a side surface of said semiconductor laminated portion forms a second reflection surface. element. 6. The reflection surface is formed on an n-type semiconductor layer formed by etching to a first depth, and formed by etching to a second depth shallower than the first depth. The group III nitride compound semiconductor light emitting device according to claim 4, wherein the n-type pedestal electrode is formed on the n-type semiconductor layer. 7. The group III nitride compound semiconductor light emitting device according to claim 4, wherein said reflection surface is formed integrally with said n-type pedestal electrode.