JP7548831B2 - Semiconductor light emitting device - Google Patents

Description

The present invention relates to a semiconductor light-emitting device.

Semiconductor elements have been used in a variety of electronic devices and are applied to optical devices such as light-emitting elements and light-receiving elements, as well as various sensors. For example, when focusing on light-emitting elements (LEDs), there is hope for the development of deep ultraviolet LEDs with an emission wavelength of 280 nm or less (hereinafter referred to as UVC-LEDs). UVC-LEDs have a structure in which an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer such as gallium nitride (GaN) are layered on a substrate such as sapphire or AlN. Since it is difficult to realize p-type AlGaN, GaN is generally used instead of AlGaN for the p-type semiconductor layer.

However, when GaN is used as the p-type semiconductor layer, the band gap of GaN is smaller than the emission wavelength energy, so the emitted light is absorbed by GaN. For this reason, when GaN is used as the p-type semiconductor layer, it is often the case that the light is extracted from the substrate side. Also, for high-intensity light-emitting elements, it is important to dissipate the heat generated when a current is applied. In particular, UVC-LEDs have a very low luminous efficiency of about 3%, so there is an issue that the light-emitting element deteriorates quickly if heat dissipation is insufficient. To address this issue, for example, Patent Document 1 proposes peeling off the semiconductor layer that constitutes the light-emitting element from the substrate and adhering it to a support substrate with high heat dissipation properties.

JP 2007-81312 A

As semiconductor elements become smaller, the effects of distortion become greater, and even when conventional technology is applied, it becomes difficult to maintain strength while also achieving high heat dissipation and suppressing the effects of heat.

The objective of the present invention is to provide a semiconductor light-emitting device that can achieve high heat dissipation and suppress the effects of heat while maintaining strength.

In a first aspect of the present invention, there is provided a semiconductor light emitting device comprising a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction,
The semiconductor light emitting element has an element substrate, a semiconductor laminate portion disposed on one surface side of the element substrate and including a first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer, a first electrode portion disposed on one surface side of the element substrate and in contact with one or more first contact regions in the first conductive type semiconductor layer, and two or more second electrode portions disposed on one surface side of the element substrate and in contact with two or more independent second contact regions in the second conductive type semiconductor layer in pairs,
In a plan view, the first contact region is disposed between the second contact regions,
the submount substrate has a third electrode portion and a fourth electrode portion,
the first metal junction portion electrically connects the first electrode portion and the third electrode portion;
the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion,
The present invention provides a semiconductor light emitting device in which at least some of the second metal junctions electrically connect a plurality of the second electrode portions to the fourth electrode portion.

In a second aspect of the present invention, there is provided a semiconductor light emitting device including a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction,
The semiconductor light emitting element has an element substrate, a semiconductor laminate portion disposed on one surface side of the element substrate and including a first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer, a first electrode portion disposed on one surface side of the element substrate and in contact with one or more first contact regions in the first conductive type semiconductor layer, and two or more second electrode portions disposed on one surface side of the element substrate and in contact with one or more second contact regions in the second conductive type semiconductor layer,
the submount substrate has a third electrode portion and a fourth electrode portion,
the first metal junction portion electrically connects the first electrode portion and the third electrode portion;
the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion,
a portion of the first conductive type semiconductor layer, the light emitting layer, and the second conductive type semiconductor layer have a mesa structure;
A semiconductor light emitting device is provided having regions in which, in a cross-sectional view, the side surface of the mesa structure, another portion of the surface of the first conductivity type semiconductor layer, and the surface of the second metal junction portion facing the element substrate are covered with an insulator.

In a third aspect of the present invention, there is provided a semiconductor light emitting device including a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction,
The semiconductor light emitting element has an element substrate, a semiconductor laminate portion disposed on one surface side of the element substrate and including a first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer, a first electrode portion disposed on one surface side of the element substrate and in contact with one or more first contact regions in the first conductive type semiconductor layer, and two or more second electrode portions disposed on one surface side of the element substrate and in contact with one or more second contact regions in the second conductive type semiconductor layer,
the submount substrate has a third electrode portion and a fourth electrode portion,
the first metal junction portion electrically connects the first electrode portion and the third electrode portion;
the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion,
The present invention provides a semiconductor light emitting device in which the sum of the contact areas of the fourth electrode portion and the second metal junction portion is larger than the total area of the upper surface of the second electrode portion.

Note that the above summary of the invention does not list all of the features of the present invention. Also, subcombinations of these features may also be inventions.

The semiconductor light-emitting device according to one aspect of the present invention makes it possible to provide a semiconductor light-emitting device that can achieve high heat dissipation and suppress the effects of heat while maintaining strength.

1 is a schematic diagram of a semiconductor light emitting element used in a semiconductor light emitting device according to a first embodiment. 2 is a schematic cross-sectional view of the schematic plan view of FIG. 1 taken along line X1-X'1 parallel to the X-axis. 2 is a schematic cross-sectional view of the schematic plan view of FIG. 1 taken along line X2-X'2 parallel to the X-axis. 1 is a schematic plan view of a submount substrate used in a semiconductor light emitting device according to a first embodiment. 4 is a schematic cross-sectional view of the schematic plan view of FIG. 3 taken along line X3-X'3 parallel to the X-axis. 4 is a schematic cross-sectional view taken along line X4-X'4 parallel to the X-axis in the schematic plan view of FIG. 1 is a cross-sectional view showing a configuration example of a semiconductor light emitting device according to a first embodiment. 1 is a cross-sectional view showing a configuration example of a semiconductor light emitting device according to a first embodiment. 10 is a schematic diagram showing the area of a contact region S1 between a fourth electrode portion and a second metal junction portion, and the area of an upper surface S2 of a second electrode portion in a semiconductor light emitting device according to a first embodiment. FIG. FIG. 4 is a schematic cross-sectional view of a semiconductor light emitting device according to a modified example of the first embodiment. 10 is a schematic plan view of a semiconductor light emitting element used in a semiconductor light emitting device according to a second embodiment. FIG. 10 is a schematic plan view of a semiconductor light emitting element used in a semiconductor light emitting device according to a second embodiment. FIG. 13 is a schematic plan view of a semiconductor light emitting element used in a semiconductor light emitting device according to a third embodiment. FIG. 11 is a schematic plan view in which the regions in which the third electrode portion and the fourth electrode portion of the sub-mount substrate are disposed are added to FIG. 10 . FIG. 11 is a schematic cross-sectional view of a semiconductor light-emitting device according to a third embodiment. FIG. 11 is a schematic cross-sectional view of a semiconductor light-emitting device according to a third embodiment.

The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

<Semiconductor Light Emitting Device of First Embodiment>
The semiconductor light emitting device of the first embodiment includes a semiconductor light emitting element, a submount substrate, a first metal joint, and a second metal joint.

<<Semiconductor Light Emitting Element in the Semiconductor Light Emitting Device of the First Embodiment>>
The semiconductor light emitting element in the semiconductor light emitting device of the first embodiment has an element substrate, a semiconductor stack portion arranged on one surface side of the element substrate and including a first conductivity type semiconductor layer, a light emitting layer, and a second conductivity type semiconductor layer, a first electrode portion arranged on one surface side of the element substrate and in contact with one or more first contact regions in the first conductivity type semiconductor layer, and two or more second electrode portions arranged on one surface side of the element substrate and in contact with two or more independent second contact regions in the second conductivity type semiconductor layer in pairs.

In a plan view, the first contact region is disposed so as to be sandwiched between the second contact regions. Here, "in a plan view, A is sandwiched between B" means that one or more line segments connecting any point constituting one B with any point constituting the other B intersects with a part of A. Also, "plan view" means, for example, viewing from the normal direction of one surface of the element substrate.

It may be preferable that a portion of the first conductive type semiconductor layer, the light emitting layer, and the second conductive type semiconductor layer have a mesa structure. In this case, it is preferable that the side surface of the mesa structure and the surface of another portion of the first conductive type semiconductor layer are covered with an insulator.

A part of the first conductive type semiconductor layer, the light emitting layer, and the second conductive type semiconductor layer have a mesa structure, and the side of the mesa structure and the surface of another part of the first conductive type semiconductor layer are covered with an insulator, so that the effects of strain are not directly transmitted to the semiconductor layer, and it is possible to achieve high heat dissipation while maintaining strength and suppressing the effects of heat.

<<Submount Substrate in Semiconductor Light Emitting Device of First Embodiment>>
The submount substrate has a third electrode portion and a fourth electrode portion. The first metal joint portion electrically connects the first electrode portion and the third electrode portion. The second metal joint portion electrically connects the second electrode portion and the fourth electrode portion. At least a portion of the second metal joint portions electrically connect the plurality of second electrode portions and the fourth electrode portion. By having at least a portion of the second metal joint portions electrically connect the plurality of second electrodes and the fourth electrode portion, it is possible to achieve high heat dissipation while maintaining strength, and to suppress the effects of heat.

<Semiconductor Light Emitting Device of Second Embodiment>
The semiconductor light emitting device of the second embodiment includes a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction. In addition, a part of the first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer have a mesa structure.

<<Semiconductor Light Emitting Element in Semiconductor Light Emitting Device of Second Embodiment>>
The semiconductor light emitting element in the semiconductor light emitting device of the second embodiment has an element substrate, a semiconductor stack portion arranged on one surface side of the element substrate and including a first conductivity type semiconductor layer, a light emitting layer, and a second conductivity type semiconductor layer, a first electrode portion arranged on one surface side of the element substrate and in contact with one or more first contact regions in the first conductivity type semiconductor layer, and two or more second electrode portions arranged on one surface side of the element substrate and in contact with one or more second contact regions in the second conductivity type semiconductor layer.

<<Submount Substrate in Semiconductor Light Emitting Device of Second Embodiment>>
The submount substrate in the semiconductor light emitting device of the second embodiment has a third electrode portion and a fourth electrode portion, the first metal junction portion electrically connects the first electrode portion and the third electrode portion, and the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion.

In a cross-sectional view, the side of the mesa structure of the semiconductor light-emitting element, the surface of another part of the first conductive type semiconductor layer, and the surface of the second metal junction facing the element substrate have areas covered with an insulator. Here, "cross-sectional view" means, for example, looking at a cross section cut along a plane perpendicular to one surface of the element substrate. This makes it possible to achieve high heat dissipation and suppress the effects of heat while maintaining strength.

The following describes the configuration features common to the semiconductor light-emitting devices of the first and second embodiments described above.

<<Insulation>>
In the semiconductor light emitting device according to the first and second embodiments, it may be preferable that at least a part of the second metal junctions be in contact with the second electrode and an insulator. By providing an insulator, the influence of strain is not directly transmitted to the semiconductor layer, and strength is maintained, while high heat dissipation is achieved to suppress the influence of heat.

In addition, it may be preferable for the insulator to cover at least a portion of the first electrode portion. By covering at least a portion of the first electrode portion with the insulator, it is possible to achieve high heat dissipation and suppress the effects of heat while maintaining strength by electrically insulating the semiconductor layer and not directly transmitting the effects of strain to the semiconductor layer.

In some cases, it may be preferable for the insulator to also cover at least a portion of the surface of the second conductive type semiconductor layer. By having the insulator also cover at least a portion of the surface of the second conductive type semiconductor layer, it is possible to achieve high heat dissipation and suppress the effects of heat while maintaining strength by electrically insulating the semiconductor layer and not directly transmitting the effects of strain to the semiconductor layer.

In some cases, it may be preferable for the insulator to contain a gas. Gas can easily expand and compress, so it can reduce the effects of strain, and while insulating, it can maintain strength without directly transmitting the effects of strain to the semiconductor layer, while also achieving high heat dissipation and suppressing the effects of heat.

In addition, from the standpoint of ease of manufacturing, it may be preferable for the gas to be atmospheric air.

The insulator may preferably be an insulating layer containing one or more of silicon oxide, silicon nitride, or silicon oxynitride.

<Semiconductor Light-Emitting Device of Third Embodiment>
The semiconductor light emitting device of the third embodiment includes a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction. In addition, it may be preferable that a part of the first conductive type semiconductor layer, the light emitting layer, and the second conductive type semiconductor layer have a mesa structure. In this case, it is preferable that the side surface of the mesa structure and the other part of the surface of the first conductive type semiconductor layer are covered with an insulator.

<<Semiconductor Light Emitting Element in the Semiconductor Light Emitting Device of the Third Embodiment>>
The semiconductor light emitting element in the semiconductor light emitting device of the third embodiment has an element substrate, a semiconductor stack portion arranged on one surface side of the element substrate and including a first conductivity type semiconductor layer, a light emitting layer, and a second conductivity type semiconductor layer, a first electrode portion arranged on one surface side of the element substrate and arranged so as to contact one or more first contact regions in the first conductivity type semiconductor layer, and two or more second electrode portions arranged on one surface side of the element substrate and contact one or more second contact regions in the second conductivity type semiconductor layer.

<<Submount Substrate in Semiconductor Light Emitting Device of Third Embodiment>>
The submount substrate in the semiconductor light emitting device of the second embodiment has a third electrode portion and a fourth electrode portion, the first metal junction portion electrically connects the first electrode portion and the third electrode portion, and the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion.

The sum of the contact areas of the third electrode portion and the first metal junction portion is greater than the total area of the top surface of the second conductivity type semiconductor layer.

By making the total contact area of the fourth electrode and the second metal junction greater than the total area of the top surface of the second electrode, the retention strength is increased, and the effects of strain are not directly transmitted to the semiconductor layer, while the strength is maintained and high heat dissipation is achieved to suppress the effects of heat.

The following describes the configuration features common to the semiconductor light-emitting devices of the first to third embodiments described above.

<Element substrate>
The element substrate in the semiconductor light emitting device of the above embodiment may be a sapphire substrate, an aluminum nitride substrate (AlN substrate), etc. From the viewpoint of improving the reliability of the semiconductor light emitting device 1, an AlN substrate is preferable, and an AlN single crystal substrate is more preferable.

The method for producing the single crystal AlN substrate is not particularly limited, but from the viewpoint of obtaining a high-quality single crystal AlN substrate, it is preferable to produce it by a sublimation method using aluminum nitride ceramics as a raw material. The dislocation density of the single crystal AlN substrate is preferably less than ¹⁰⁷ cm ^-2 , and more preferably less than ¹⁰⁵ cm ^-2 . From the viewpoint of reducing the dislocation density of the first conductivity type semiconductor layer, it is preferable that the RMS surface roughness of the AlN single crystal substrate is less than about 1 nm for an area of 10 μm x 10 μm.

<Semiconductor laminate>
The semiconductor laminate in the semiconductor light emitting device of the above-described embodiment is required to include at least a first conductivity type semiconductor layer, a light emitting layer, and a second conductivity type semiconductor layer, and may include layers other than these.

The first conductive type semiconductor layer and the second conductive type semiconductor layer are semiconductor layers that exhibit different electrical conductivities. For example, when one is an n-type semiconductor layer, the other is a p-type semiconductor layer. From the viewpoint of improving the crystallinity of the semiconductor laminate as a whole, it may be preferable that the first conductive type semiconductor layer is an n-type semiconductor layer and the second conductive type semiconductor layer is a p-type semiconductor layer.

As a layer other than the first conductive type semiconductor layer, the light emitting layer, and the second conductive type semiconductor layer, for example, a layer that blocks electrons or holes may be provided between the light emitting layer and the first conductive type semiconductor layer and/or the second conductive type semiconductor layer. In addition, from the viewpoint of improving the ohmic contact with the submount substrate, a contact layer doped with a high concentration of impurities may be provided.

The semiconductor laminate can be formed, for example, by MOCVD (Metal Organic Chemical Vapor Deposition). To make the semiconductor laminate into a mesa structure, the thin film layers that make up the semiconductor laminate can be formed by MOCVD or the like, and then the desired regions can be etched.

<Light-emitting layer>
The light emitting layer emits light according to the band gap of the light emitting layer when electric power is applied. The semiconductor light emitting device of the present embodiment is particularly suitable for use in applications where high reliability is required in the past, because sufficient reliability is ensured even when a semiconductor light emitting element that emits ultraviolet light with a central emission wavelength of 210 nm or more and 320 nm or less is used, which required reliability to be ensured.

A preferred example of the light-emitting layer is a multi-quantum well structure. For example, a multi-quantum well structure can be used in which multiple AlGaN layers with different composition ratios (different bandgaps) are stacked.

<Submount substrate>
The submount substrate is electrically connected to the semiconductor light emitting element. From the viewpoint of improving the heat dissipation of the semiconductor light emitting device, the base portion is preferably made of a material with high heat dissipation properties. An example of the material with high heat dissipation properties is AlN ceramic.

<First electrode portion>
The first electrode portion is not particularly limited as long as it is disposed so as to be in contact with at least one first contact region on the first conductive type semiconductor layer. When the first conductive type semiconductor layer is an n-type semiconductor layer, the first electrode portion is preferably made of a material containing aluminum and nickel from the viewpoint of reducing the contact resistance. The material constituting the n-type semiconductor layer is preferably a single crystal or mixed crystal of AlN, GaN, or InN, and a specific example is n-type Al _x Ga _(1-x) N (0≦x≦1). In addition, these materials may contain Group V elements other than N, such as P, As, and Sb, and impurities such as C, H, F, O, Mg, and Si.

<Second electrode portion>
The second electrode portion is not particularly limited as long as it is arranged so as to contact two or more independent second contact regions in the second conductive type semiconductor layer in pairs. When the second conductive type semiconductor layer is a p-type semiconductor layer, if the purpose is to inject holes into the nitride semiconductor element, for example, Ni, Au, Pt, Ag, Rh, Pd, Pt, Cu and their alloys, or ITO, etc. are applied to the second electrode portion. When the second conductive type semiconductor layer is a p-type semiconductor layer, it is preferable that Ni, Au or their alloys, or ITO, which have a small contact resistance with the nitride semiconductor layer, are applied to the second electrode portion.

For connection, the second electrode portion may be formed continuously of, for example, Au, Al, Cu, Ag, W, etc., and among these, Au having high conductivity is preferable. In addition, in order to improve adhesion, the second electrode portion may contain Ti at the interface with the second conductive type semiconductor layer.
<Third Electrode Unit and Fourth Electrode Unit>

There are no particular limitations on the third electrode portion as long as it can be electrically connected to the first electrode portion via the first metal junction. An example of the third electrode portion is a configuration containing Ni, Au, Ti, W, Al, etc. From the viewpoint of adhesion and retention strength, it is preferable that the material constituting the third electrode portion is an alloy containing Ni and Au.

<First metal joint and second metal joint>
The first metal joint is not particularly limited as long as it electrically connects the first electrode part and the third electrode part. An example of the first metal joint is a structure containing Au, Al, Cu, Ag, and W. The material constituting the first metal joint is preferably a material containing Au, which has high conductivity, and more preferably a material containing Au and Sn, since it has a low melting point and can suppress the generation of stress during bonding.

The second metal joint is not particularly limited as long as it electrically connects the second electrode portion and the fourth electrode portion. An example of the second metal joint is a composition containing Au, Al, Cu, Ag, and W. The material constituting the second metal joint is preferably a material containing Au, which has high conductivity, and more preferably a material containing Au and Sn, since it has a low melting point and can suppress the generation of stress during joining. The material constituting the second metal joint may be the same as the material constituting the first metal joint, or may be different.

<Semiconductor Light Emitting Device>
The semiconductor light emitting element of this embodiment may be such that at least a portion of it reaches 55° C. or higher when 4 W of power is supplied between the first electrode portion and the second electrode portion for 10 seconds at an environmental temperature of 25° C. The semiconductor light emitting element of this embodiment achieves high heat dissipation even when heat is generated when power is supplied, so that deterioration of the light emitting characteristics of the semiconductor light emitting element is suppressed, and a highly reliable semiconductor light emitting element can be achieved.

From the viewpoint of suppressing manufacturing variations, the semiconductor light emitting element of this embodiment may have a region where a part of the surface of the first electrode portion does not contact the first metal junction portion. In addition, the area of the region of the first electrode portion that does not contact the first metal junction portion in a planar view may be 20% or more and 50% or less of the total area of the first electrode portion in a planar view.

<Example>
Next, the semiconductor light emitting device of this embodiment will be described in more detail with reference to the drawings.

The definitions of up and down and other directions in the following explanation are merely for the convenience of explanation and do not limit the technical ideas of this disclosure. For example, if an object is rotated 90 degrees and observed, up and down are converted into left and right and read, and of course, if it is rotated 180 degrees and observed, up and down are read inverted.

In the following description, directions may be described using the terms X-axis, Y-axis, and Z-axis. For example, the X-axis and Y-axis directions are parallel to one surface 11a of the element substrate 11. The Z-axis direction is the normal direction to one surface 11a of the element substrate 11. The X-axis, Y-axis, and Z-axis directions are perpendicular to each other.

<Semiconductor Light Emitting Device of the First Example>
Fig. 1 is a schematic plan view of a semiconductor light emitting element 10 used in a semiconductor light emitting device 1 according to a first embodiment of the present invention. Fig. 2A is a schematic cross-sectional view of the schematic plan view of Fig. 1 taken along line X1-X'1 parallel to the X-axis. Fig. 2B is a schematic cross-sectional view of the schematic plan view of Fig. 1 taken along line X2-X'2 parallel to the X-axis.

1 to 2B, the semiconductor light emitting element 10 includes an element substrate 11 and a semiconductor laminate 12 provided on one surface 11a of the element substrate 11. The semiconductor laminate 12 includes a first conductive type semiconductor layer 121, a light emitting layer 122, and a second conductive type semiconductor layer 123. The semiconductor laminate 12 includes a portion 121A of the first conductive type semiconductor layer, another portion 121B of the first conductive type semiconductor layer, a light emitting layer 122 provided on the portion 121A of the first conductive type semiconductor layer, and a second conductive type semiconductor layer 123 provided on the light emitting layer 122. The semiconductor laminate 12 includes a mesa structure 12A including a portion 121A of the first conductive type semiconductor layer, the light emitting layer 122, and the second conductive type semiconductor layer 123. In the embodiment shown in FIG. 1, the semiconductor laminate 12 includes two independent (i.e., spaced apart) mesa structures.

A first electrode portion 13 is arranged on the other part 121B of the first conductive type semiconductor layer so as to contact the first contact region C1. The first electrode portion 13 is arranged on one surface 11a of the element substrate 11 and is in contact with one first contact region C1 in the other part 121B of the first conductive type semiconductor layer. A second electrode portion 14 is arranged on the second conductive type semiconductor layer 123 so as to contact the second contact region C2. The second electrode portion 14 is arranged on one surface 11a of the element substrate 11 and is in contact with two independent second contact regions C2 in the second conductive type semiconductor layer 123 in pairs. The first contact region C1 is arranged so as to be sandwiched between the second contact regions C2.

Figure 3 is a schematic plan view of a submount substrate 20 used in a semiconductor light-emitting device according to a first embodiment of the present invention. Figure 4A is a schematic cross-sectional view of the schematic plan view of Figure 3 cut along line X3-X'3 parallel to the X-axis. Figure 4B is a schematic cross-sectional view of the schematic plan view of Figure 3 cut along line X4-X'4 parallel to the X-axis. Note that Figure 3 shows the back surface of the submount substrate 20. The back surface of the submount substrate 20 shown in Figure 3 corresponds to the lower surface of the submount substrate 20 in Figures 4A and 4B. As shown in Figures 3 to 4B, the submount substrate 20 includes a substrate body 23, and a third electrode portion 21 and a fourth electrode portion 22 formed on the substrate body 23.

Figures 5A and 5B are cross-sectional views showing an example of the configuration of the semiconductor light-emitting device 1 according to Example 1 of the present invention. The submount substrate 20 shown in Figure 3 is turned over, placed opposite the semiconductor light-emitting element 10 shown in Figure 1, and bonded to each other via the first metal bonding portion 31 and the second metal bonding portion 32, thereby obtaining the semiconductor light-emitting device 1 shown in Figures 5A and 5B.

As shown in FIG. 5A, in the semiconductor light emitting element 10, one first electrode portion 13 is disposed on one surface 11a side of the element substrate 11. The one first electrode portion 13 is in contact with a first contact region C1 in another part 121B of the first conductive type semiconductor layer. The first metal junction portion 31 is disposed between the semiconductor light emitting element 10 and the submount substrate 20. The first metal junction portion 31 electrically connects the first electrode portion 13 and the third electrode portion 21 of the submount substrate 20.

As shown in FIG. 5B, in the semiconductor light emitting element 10, two second electrode portions 14 are arranged on one surface 11a side of the element substrate 11. The two second electrode portions 14 are in paired contact with two independent first contact regions C1 in a portion 121A of the first conductive type semiconductor layer 121. The second metal junction portion 32 electrically connects the two second electrode portions 14 to the fourth electrode portion 22 of the submount substrate 20. In addition, the side surface of the mesa structure 12A, the other portion 121B of the first conductive type semiconductor layer, and the surface of the second metal junction portion 32 facing the element substrate 11 are covered with air 41 as an insulator.

Figure 6 is a schematic diagram showing the area of the contact region S1 between the fourth electrode portion 22 and the second metal junction portion 32 and the area of the upper surface S2 of the second electrode portion 14 (area inside the solid line) in the semiconductor light emitting device 1 according to the first embodiment of the present invention. Other elements are shown by dotted lines. As is clear from Figure 6, the area of the contact region S1 between the fourth electrode portion 22 and the second metal junction portion 32 (area inside the two-dot dashed line) is greater than the sum of the areas of the upper surfaces S2 of the second electrode portions 14.

By adopting such a structure, the semiconductor light-emitting device 1 can achieve high heat dissipation while maintaining its strength, thereby suppressing the effects of heat.

<<Modifications>>
7 is a schematic cross-sectional view of a semiconductor light-emitting device 1A according to a modified example of the first embodiment of the present invention. The cross section of the semiconductor light-emitting device 1A shown in FIG. 7 corresponds to the cross section along the line X2-X'2 in FIG. 1 and the cross section along the line X4-X'4 in FIG. 3. The semiconductor light-emitting device 1A shown in FIG. 7 is different from the semiconductor light-emitting device 1 shown in FIG. 5B in that the insulator covering the side surface of the mesa structure 12A and the surface of the other part 121B of the first conductive type semiconductor layer is an insulating layer 42, not air 41. The insulating layer 42 may be, for example, a single layer film made of silicon oxide, silicon nitride, or silicon oxynitride, or may be a laminated film including one or more of these.

Even with this structure, the semiconductor light-emitting device 1A is able to maintain its strength while achieving high heat dissipation and suppressing the effects of heat.

<Semiconductor Light Emitting Device of the Second Example>
8 and 9 are schematic plan views of a semiconductor light emitting element 10 used in a semiconductor light emitting device 1B according to a second embodiment of the present invention. FIG. 8 is a diagram illustrating a contact region S1 and an upper surface S2 of a second electrode portion 14 in a semiconductor light emitting device 1B according to a second embodiment. FIG. 9 is a diagram illustrating two second contact regions C2 and a bridge region B1 connecting the two second contact regions C2. Note that the configuration of the submount substrate 20 used in the semiconductor light emitting device 1B according to the second embodiment is the same as that of the submount substrate 20 (see FIG. 3) used in the semiconductor light emitting device 1 according to the first embodiment, and therefore the repeated illustration is omitted.

As shown in Figures 8 and 9, the semiconductor light-emitting element 10B according to the second embodiment differs from the semiconductor light-emitting element 10 shown in Figure 1 in that the two second contact regions C2 are connected via a bridge region B1. In the semiconductor light-emitting element 10B, the two second contact regions C2 are connected and integrated via the bridge region B1. This integrated structure forms a mesa structure 12A (see Figure 2B). Other than this, the configuration of the semiconductor light-emitting element 10B is the same as that of the semiconductor light-emitting element 10.

Therefore, similar to the semiconductor light emitting device 10 shown in FIG. 2B, in the semiconductor light emitting device 10B, the side of the mesa structure 12A, the other part 121B of the first conductivity type semiconductor layer, and the surface of the second metal junction portion facing the element substrate are covered with air 41 as an insulator.

In addition, the area of the contact region S1 between the fourth electrode portion 22 and the second metal joint portion 32 is greater than the sum of the areas of the upper surfaces S2 of the second electrodes 14.

By adopting such a structure, it is possible to ensure a wide bonding surface between the semiconductor light emitting element 10 and the second metal bonding portion 32, and a wide bonding surface between the second metal bonding portion 32 and the submount substrate 20, and it is possible to increase the bonding strength between the semiconductor light emitting element 10 and the submount substrate 20. As a result, the semiconductor light emitting device 1B can achieve high heat dissipation and suppress the effects of heat while still maintaining its strength.

<Semiconductor Light Emitting Device of the Third Example>
Fig. 10 is a schematic plan view of a semiconductor light emitting element 10 used in a semiconductor light emitting device 1C according to a third embodiment of the present invention. Fig. 11 is a schematic plan view in which the regions in which the third electrode portion 21 and the fourth electrode portion 22 of the submount substrate 20 are arranged are added to Fig. 10. Figs. 12A and 12B are schematic cross-sectional views of the semiconductor light emitting device 1C according to the third embodiment of the present invention. Fig. 12A shows a cross section taken along line X5-X'5 in Fig. 11. Fig. 12B shows a cross section taken along line X6-X'6 in Fig. 11.

Compared to the semiconductor light emitting device 1 according to the first embodiment, the semiconductor light emitting device 1C according to the third embodiment has a plurality of first contact regions C1 where the first electrode portion 13 contacts the first conductive type semiconductor layer 121. Also, there are a plurality of second contact regions C2 where the second electrode portion 14 contacts the second conductive type semiconductor layer 123. The first electrode portion 13 has a comb shape in a plan view, and the second electrode portion 14 is disposed between adjacent combs. In other words, the first contact region C1 is sandwiched between the second contact regions C2 or is adjacent to the second contact region C2.

By adopting such a structure, the semiconductor light-emitting device 1C can more efficiently supply power to the light-emitting portion (e.g., the light-emitting layer 122), and can achieve high heat dissipation while maintaining strength and suppressing the effects of heat.

1 Semiconductor light emitting device 10 Semiconductor light emitting element 11 Element substrate 11a One surface of element substrate 121 First conductive type semiconductor layer 121A Part of first conductive type semiconductor layer 121B Other part of first conductive type semiconductor layer 122 Light emitting layer 123 Second conductive type semiconductor layer 12 Semiconductor laminate portion 12A Mesa structure 13 First electrode portion 14 Second electrode portion 20 Submount substrate 21 Third electrode portion 22 Fourth electrode portion 23 Substrate body 31 First metal junction portion 32 Second metal junction portion 42 Insulator (insulating layer)
C1: First contact region C2: Second contact region B1: Bridge region S1: Contact region S2: Upper surface of second electrode portion

Claims (15)

A semiconductor light emitting device comprising a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction,
The semiconductor light emitting device is
An element substrate;
a semiconductor laminate portion disposed on one surface side of the element substrate, the semiconductor laminate portion including a first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer;
a first electrode portion disposed on one surface side of the element substrate and in contact with one or more first contact regions in the first conductive type semiconductor layer;
two or more second electrode portions that are disposed on one surface side of the element substrate and are in contact with two or more independent second contact regions in the second conductive type semiconductor layer, respectively ;
In a plan view, the first contact region is disposed between the second contact regions,
the submount substrate has a third electrode portion and a fourth electrode portion,
the first metal junction portion electrically connects the first electrode portion and the third electrode portion;
the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion,
the second metal joint portion is in contact with a plurality of the second electrode portions across the second metal joint portion;
At least a portion of the second metal junctions electrically connect a plurality of the second electrode portions to the fourth electrode portion. a portion of the first conductive type semiconductor layer, the light emitting layer, and the second conductive type semiconductor layer have a mesa structure;
The semiconductor light emitting device according to claim 1 , wherein a side surface of the mesa structure and another part of a surface of the first conductive type semiconductor layer are covered with an insulator. A semiconductor light emitting device comprising a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction,
The semiconductor light emitting device is
An element substrate;
a semiconductor laminate portion disposed on one surface side of the element substrate, the semiconductor laminate portion including a first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer;
a first electrode portion disposed on one surface side of the element substrate and in contact with one or more first contact regions in the first conductive type semiconductor layer;
two or more second electrode portions that are disposed on one surface side of the element substrate and that are in contact with two or more second contact regions in the second conductive type semiconductor layer, respectively ;
the submount substrate has a third electrode portion and a fourth electrode portion,
the first metal junction portion electrically connects the first electrode portion and the third electrode portion;
the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion,
the second metal joint portion is in contact with a plurality of the second electrode portions across the second metal joint portion;
a portion of the first conductive type semiconductor layer, the light emitting layer, and the second conductive type semiconductor layer have a mesa structure;
A semiconductor light emitting device having, in a cross-sectional view, areas where the side of the mesa structure, the surface of another portion of the first conductivity type semiconductor layer, and the surface of the second metal junction facing the element substrate are covered with an insulator. The semiconductor light emitting device according to claim 2 , wherein at least a portion of the second metal junction portion is in contact with the second electrode portion and the insulator. The semiconductor light emitting device according to claim 2 , wherein the insulator further covers at least a part of the first electrode portion. The semiconductor light emitting device according to claim 2 , wherein the insulator also covers at least a part of a surface of the second conductive type semiconductor layer. The semiconductor light emitting device according to claim 2 , wherein the insulator contains a gas. The semiconductor light emitting device according to claim 7 , wherein the gas is atmospheric air. The semiconductor light-emitting device according to any one of claims 2 to 8, wherein the insulator includes one or more of silicon oxide, silicon nitride, and silicon oxynitride. The semiconductor light emitting device according to claim 1 , wherein a total contact area between the third electrode portion and the first metal junction portion is greater than a total area of an upper surface of the second conductivity type semiconductor layer. A semiconductor light emitting device comprising a semiconductor light emitting element, a submount substrate, a first metal junction, and a second metal junction,
The semiconductor light emitting device is
An element substrate;
a semiconductor laminate portion disposed on one surface side of the element substrate, the semiconductor laminate portion including a first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer;
a first electrode portion disposed on one surface side of the element substrate and in contact with one or more first contact regions in the first conductive type semiconductor layer;
two or more second electrode portions arranged on one surface side of the element substrate and in contact with two or more second contact regions in the second conductive type semiconductor layer, respectively ;
having
the submount substrate has a third electrode portion and a fourth electrode portion,
the first metal junction portion electrically connects the first electrode portion and the third electrode portion;
the second metal junction portion electrically connects the second electrode portion and the fourth electrode portion,
the second metal joint portion is in contact with a plurality of the second electrode portions across the second metal joint portion;
A semiconductor light emitting device, wherein a total contact area between the fourth electrode portion and the second metal junction portion is greater than a total area of an upper surface of the second electrode portion. The semiconductor light-emitting device according to any one of claims 1 to 11, wherein the first metal junction and the second metal junction contain one or more of Au, Sn, Cu, and Ag. The semiconductor light-emitting device according to claim 1 , wherein at least a portion of the first electrode portion and the second electrode portion reaches 55° C. or higher when a current of 4 W is supplied between the first electrode portion and the second electrode portion for 10 seconds at an environmental temperature of 25° C. The semiconductor light-emitting device according to any one of claims 1 to 13, wherein a portion of the surface of the first electrode portion has an area that is not in contact with the first metal junction portion. The semiconductor light-emitting device according to claim 14, wherein the area of the region of the first electrode portion that is not in contact with the first metal junction portion in a plan view is 20% to 50% of the total area of the first electrode portion in a plan view.

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