JP2023126349A - Light-emitting device - Google Patents

Abstract

To achieve a package that suppresses cracking, breakage, and delamination on a light-emitting device.SOLUTION: A light-emitting device has a base part and a frame part. The base part has a light-emitting element, a first surface on which the light-emitting element is arranged, and a convex part formed on a side of the first surface outside of an area on which the light-emitting element is arranged. The frame part is made of a material as a main material having a coefficient of thermal expansion different from that of the main material used on the base part. The frame part has a bonding surface to be bonded to a protruding upper surface of the convex part of the base part and surrounds the light-emitting element arranged on the first surface.SELECTED DRAWING: Figure 9

Description

The present invention relates to a light emitting device.

2. Description of the Related Art Conventionally, light emitting devices have been known in which a light emitting element such as an LED element or a semiconductor laser element is arranged in a package having a frame and a bottom surface. For example, Patent Document 1 discloses a semiconductor element housing package that includes a ceramic laminate and a heat dissipation member made of a metal material. Furthermore, a lid is joined to the semiconductor element housing package with the semiconductor element placed on the heat dissipation member, and a semiconductor device housing the semiconductor element is manufactured.

As described in Patent Document 1, when a semiconductor element operates, heat is generated due to this operation. The influence of this heat also affects the semiconductor element housing package constituting the semiconductor device. Generally, ceramics and metals have different thermal expansion coefficients and material strengths. In addition, the properties of the materials, such as resistance to cracking and resistance to bending, differ.

WO2014/017273

As exemplified in Patent Document 1, when forming a package by joining members made of different materials, it is necessary to consider the size of the package and the shape of each member to prevent cracking, damage, and peeling. Desired.

A light emitting device disclosed in the present application includes a light emitting element, a first surface where the light emitting element is arranged, and a convex portion formed outside a region where the light emitting element is arranged on the side of the first surface. , the main material is a material having a different coefficient of thermal expansion from the main material used for the base, and has a joint surface that joins to the protruding upper surface of the convex part of the base, and is arranged on the first surface. and a frame portion surrounding the light emitting element.

Further, the package disclosed in the present application forms a cavity surrounding a light emitting element, and has a first surface where the light emitting element is disposed, and a cavity outside the area where the light emitting element is disposed on the side of the first surface. a base having a convex portion formed therein; an outer surface; a first upper surface and a first lower surface intersecting the outer surface; and a second lower surface formed between the first upper surface and the first lower surface; a frame portion having a base portion and a frame portion, the main materials forming the base portion and the frame portion are materials having different thermal expansion coefficients, and the protruding upper surface of the convex portion is 2 is joined to the lower surface.

Further, the base disclosed in the present application includes an outer surface, a first upper surface and a first lower surface that intersect with the outer surface, and a second lower surface formed between the first upper surface and the first lower surface. a base that forms a cavity surrounding a light-emitting element, the base joining with a frame having a first surface on which the light-emitting element is disposed, and a base on the outside of a region on the side of the first surface where the light-emitting element is disposed; a convex portion formed, the main material being a material having a different coefficient of thermal expansion from the main material used for the frame portion, and the protruding upper surface of the convex portion being joined to the second lower surface of the frame portion. Ru.

According to the present invention, it is possible to provide a light emitting device that is mounted using a package that is formed by bonding different materials and that is suppressed from cracking, damage, peeling, and the like.

Further, according to the present invention, it is possible to provide a package in which occurrence of cracking, damage, peeling, etc. is suppressed, or a base suitable for forming such a package.

FIG. 1 is a perspective view of a light emitting device including a mounting board according to a first embodiment. FIG. 2 is a perspective view of the light emitting device according to the first embodiment. FIG. 3 is a perspective view of the light emitting device according to the first embodiment, viewed from the same direction as FIG. 2 with a part of its configuration removed. FIG. 4 is a top view of the light emitting device according to the first embodiment, corresponding to FIG. 3. FIG. 5 is a perspective view of the frame portion of the light emitting device according to the first embodiment, viewed from the top side. FIG. 6 is a perspective view of the frame portion of the light emitting device according to the first embodiment, viewed from the bottom side. FIG. 7 is a perspective view of the base of the light emitting device according to the first embodiment, viewed from the top side. FIG. 8 is a top view of the light emitting device according to the first embodiment in a state where the base and the frame are joined. FIG. 9 is a cross-sectional view of a state in which the base portion and the frame portion are joined along a straight line connecting IX-IX in FIG. 8. FIG. 10 is a cross-sectional view of a state in which the base portion and the frame portion are joined along a straight line connecting XX in FIG. 8. FIG. 11 is a sectional view of the light emitting device according to the second embodiment in a state where the base and the frame are joined. FIG. 12 is a sectional view of the light emitting device according to the third embodiment in a state where the base and the frame are joined. FIG. 13 is a cross-sectional view of the light emitting device according to the fourth embodiment in a state where the base and the frame are joined.

In this specification or the claims, polygons such as triangles and quadrilaterals include shapes whose corners have been rounded, chamfered, chamfered, rounded, etc. shall be called. Furthermore, not only the corners (edges of sides) but also shapes in which the middle portions of the sides are processed are also referred to as polygons. In other words, shapes processed based on polygons are included in the interpretation of "polygon" described in this specification and claims.

Furthermore, the same applies to words expressing specific shapes, such as not only polygons but also trapezoids, circles, and irregularities. The same holds true when dealing with each side forming the shape. In other words, even if a corner or middle part of a certain side is processed, the interpretation of "side" includes the processed part. In addition, when distinguishing a "polygon" or "side" that has not been intentionally processed from a processed shape, add "strict" and write, for example, "strict quadrilateral". shall be taken as a thing.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated, referring drawings. However, although the illustrated form embodies the technical idea of the present invention, it does not limit the present invention. Furthermore, in the following description, the same names and symbols indicate the same or homogeneous members, and duplicate descriptions may be omitted as appropriate. Note that the sizes, positional relationships, etc. of members shown in each drawing may be exaggerated for clarity of explanation.

<First embodiment>
FIG. 1 is a perspective view of a state in which a light emitting device 1 and a substrate 2 according to the first embodiment are joined. FIG. 2 is a perspective view of the light emitting device 1. FIG. 3 is a perspective view for explaining the internal structure of the light emitting device 1. As shown in FIG. FIG. 4 is a top view for explaining the internal structure of the light emitting device 1. FIG. 5 is a perspective view of the frame 20 in the light emitting device 1 from the top side. FIG. 6 is a perspective view of the frame 20 in the light emitting device 1 from the bottom side. FIG. 7 is a perspective view of the bottom of the light emitting device 1 from the top side. FIG. 8 is a top view of the base 10 and frame 20 in the light emitting device 1. FIG. 9 is a sectional view taken along line IX-IX in FIG. 8. FIG. 10 is a sectional view taken along line XX in FIG. 8.

The light emitting device 1 includes a base 10, a frame 20, three semiconductor laser elements 30, three submounts 40, three light reflecting members 50, a protection element 70, and a lid member 80 as components. Further, the light emitting device 1 is bonded to the substrate 2.

As shown in FIG. 7, the base 10 has a shape in which a convex portion 104 is provided near the outer periphery of the upper surface of the flat plate. Further, the base 10 has a first surface 101 corresponding to an upper surface, a second surface 102 corresponding to a lower surface, an outer surface 103, and a convex portion 104. The first surface 101 is on the opposite side of the second surface 102 and is not directly visible from the top view of FIG. The outer surface 103 intersects the first surface 101 and the second surface 102 . The convex portion 104 is provided near the periphery where the first surface 101 and the outer surface 103 intersect on the first surface 101 side.

The protruding portions of the convex portion 104 include a convex outer surface 106 that is the outer surface forming the protruding portion, a convex inner surface 107 that is the inner surface forming the protruding portion, and a convex outer surface 106 that forms the protruding upper surface of the protruding portion. It has a convex upper surface 105 which is an upper surface intersecting with the convex inner surface 107. The convex portion 104 protrudes upward on the first surface 101 side at a position spaced apart from the position where it intersects with the outer surface 103, and a convex upper surface 105 is formed inward from the protruding position. That is, the convex outer surface 106 is formed inside the outer surface 103 of the base 10 .

The height of the convex portion 104, in other words, the height from the first surface 101 of the base 10 to the convex upper surface 105 is smaller than the thickness from the second surface 102 to the first surface 101 of the base 10. For example, the thickness from the second surface 102 to the first surface 101 of the base 10 is formed in the range of 0.2 mm to 1.0 mm, and the height of the convex portion 104 is formed in the range of 0.2 mm to 0.5 mm. Ru. Preferably, the thickness from the second surface 102 to the first surface 101 of the base 10 is 0.5 mm or more, and the height of the convex portion 104 is preferably less than 0.5 mm. By doing so, stable bonding can be achieved, and the size of the light emitting device 1 can be reduced.

The overall shape of the base 10 is a rectangular parallelepiped with a convex portion 104 near the outer edge of one side. Such a base 10 can be made of metal, for example. Here, the expression "made of metal" includes cases where it is made only of metal and cases where it is made mainly of metal. Specifically, the base 10 is made of copper. Further, metals other than copper such as copper, aluminum, and iron, and composites such as copper molybdenum, copper-diamond, and copper tungsten can also be used.

The frame portion 20 forms a frame. It also has a first upper surface 201, a second upper surface 202, a first lower surface 203, a second lower surface 204, an outer surface 205, a first inner surface 206, a second inner surface 207, and a third inner surface 208. The first upper surface 201 and the first lower surface 203 intersect with the outer surface 205. Both a second upper surface 202 and a second lower surface 204 are formed between the first upper surface 201 and the first lower surface 203. The second upper surface 202 is formed between the first upper surface 201 and the second lower surface 204. The second lower surface 204 is formed between the second upper surface 202 and the first lower surface 203.

Opposite the outer surface 205, the first upper surface 201 intersects the first inner surface 206. Opposite the outer surface 205, the first lower surface 203 intersects the second inner surface 207. Opposite the first upper surface 201 , a portion of the first inner surface 206 intersects the second lower surface 204 and another portion intersects the second upper surface 202 . That is, a portion of the first inner surface 206 continues to the second lower surface 204 and the rest intersects with the second upper surface 202 above the second lower surface 204. Further, the second upper surface 202 is partially provided in the frame portion 20.

Opposite the first inner surface 206 , the second upper surface 202 intersects the third inner surface 208 . Opposite the second upper surface 202, the third inner surface 208 intersects the second lower surface 204. Therefore, in the region having the second upper surface 202, a step is formed inward from the first inner surface 206 based on the second upper surface 202 and the third inner surface 208.

Regarding the entire inner surface of the frame portion 20, when looking at the direction perpendicular to the first lower surface 203, there is a region having the first inner surface 206 and a third inner surface 208, and a region having the first inner surface 206. , and a region that does not have the third inner surface 208. In the former region, the second inner surface 207 is closer to the outer surface 205 than the first inner surface 206 and the third inner surface 208 are. In the latter region, the second inner surface 207 is closer to the outer surface 205 than the first inner surface 206 . Note that in the former region, the second inner surface 207 may be the same as the first inner surface 206, or may be located closer to the third inner surface 208 than the first inner surface 206.

The frame portion 20 can be formed using ceramic as a main material. Specifically, the frame portion 20 is formed using aluminum oxide (alumina) as a main material as a ceramic. Moreover, aluminum nitride, silicon nitride, silicon carbide, etc. can also be employed as a ceramic whose main material is other than aluminum oxide. A metal film 209 is provided on the second upper surface 202 and the first lower surface 203 of the frame portion 20, respectively. Moreover, the metal film 209 on the second upper surface 202 and the metal film 209 on the first lower surface 203 can be electrically connected by the metal passing through the inside of the base 10 .

The semiconductor laser element 30 has a lower surface, an upper surface, and a side surface, and emits laser light from one side surface. As the three semiconductor laser elements 30, for example, a semiconductor laser element 30 that emits blue light can be used. Note that the semiconductor laser element 30 that emits light of not only blue but another color such as red or green may also be used. Moreover, all the semiconductor laser elements 30 mounted on the light emitting device 1 do not have to emit light of the same color. For example, three semiconductor laser elements 30 may be configured by employing one each of blue, green, and red semiconductor laser elements 30.

Here, blue light refers to light whose emission peak wavelength is within the range of 420 nm to 494 nm. Examples of the semiconductor laser device 30 that emits blue light include a semiconductor laser device 30 that includes a nitride semiconductor. As the nitride semiconductor, for example, GaN, InGaN, and AlGaN can be used.

Red light refers to light whose emission peak wavelength is within the range of 605 nm to 750 nm. Examples of the semiconductor laser element 30 that emits red light include those containing InAlGaP-based, GaInP-based, GaAs-based, and AlGaAs-based semiconductors.

Green light refers to light whose emission peak wavelength is within the range of 495 nm to 570 nm. Examples of the semiconductor laser device 30 that emits green light include a semiconductor laser device 30 containing a nitride semiconductor. As the nitride semiconductor, for example, GaN, InGaN, and AlGaN can be used.

The submount 40 has a lower surface, an upper surface, and side surfaces, and is configured in the shape of a rectangular parallelepiped. Note that the shape is not limited to a rectangular parallelepiped. Submount 40 can be formed using silicon nitride, aluminum nitride, or silicon carbide, for example. In addition, other materials can also be used. Further, a metal film is provided on the upper surface of the submount 40.

The light reflecting member 50 has a lower surface, an upper surface, a side surface, and a light reflecting surface. The side surface intersects with the lower surface, and on the opposite side from the lower surface, intersects with the upper surface and the light reflecting surface. Further, the light reflecting surface is a flat surface, intersects with the upper surface, slopes from the upper surface to the lower surface, and intersects with the side surface on the lower surface side. Therefore, the light reflecting surface is provided with a height from the lower surface equal to the height of the side surfaces that intersect on the lower surface side. The light reflecting surface is designed to form an angle of 45 degrees with the lower surface. Note that this angle does not need to be limited to 45 degrees, and the light reflecting surface may be a curved surface instead of a flat surface.

The light reflecting member 50 can be formed, for example, by forming its outer shape from a main material and forming a light reflecting film on a surface of the formed outer shape on which a light reflecting surface is to be provided. The main material is preferably a heat-resistant material, such as glass such as quartz or BK7 (borosilicate glass), metal such as aluminum, or Si. The light reflecting film is preferably made of a material with high light reflectance, such as metals such as Ag or Al, or dielectric multilayer films such as Ta ₂ O ₅ /SiO ₂ , TiO ₂ /SiO ₂ , Nb ₂ O ₅ /SiO _2, etc. can do.

Note that if the outer shape is formed using a material with high light reflectance such as metal as the main material, the formation of the light reflective film may be omitted. The light reflecting surface can have a light reflectance of 99% or more with respect to the peak wavelength of the laser light to be reflected. These light reflectances can be 100% or less or less than 100%. The protection element 70 is, for example, a Zener diode.

The lid member 80 has a lower surface, an upper surface, and side surfaces, is configured in the shape of a rectangular parallelepiped, and is transparent as a whole. Note that a portion may have a non-light-transmitting area. Further, the shape is not limited to a rectangular parallelepiped. The lid member 80 can be formed using sapphire as a main material. Further, a metal film is provided in some areas. Sapphire is a material with a relatively high refractive index and relatively high strength. Note that, in addition to sapphire, for example, glass or the like can also be used as the main material.

Substrate 2 has a lower surface, side surfaces, and an upper surface. Furthermore, there is a region on the upper surface of the substrate 2 in which a metal film and an insulating film are provided. The substrate 2 is mainly made of metal, such as aluminum or copper. Note that it may be formed of a plurality of metals or may be formed of a plurality of metal layers.

Next, a light emitting device 1 manufactured using these components will be described.
First, the base 10 and the frame 20 are joined together to form a package in which the semiconductor laser element is placed. The base 10 and the frame 20 are joined at the convex upper surface 105 of the base 10 and the second lower surface 204 of the frame 20, respectively. For example, it can be joined to the second lower surface 204 of the frame portion 20 using Ag solder, Au solder, AuSn, or the like.

Compared to the outer diameters of the first surface 101 and the second surface 102 of the base 10, the opening formed by the first lower surface 203 of the frame section 20 is larger than this, and the opening formed by the second lower surface 204 of the frame section 20 is larger than this. small. Therefore, the structural relationship between the base 10 and the frame 20 is that the base 10 can enter the frame from the first lower surface 203 side of the frame 20, and the convex upper surface 105 of the base 10 is connected to the second lower surface 204 of the frame 20. The structure is such that further intrusion is stopped once contact is made.

In a state where the base portion 10 and the frame portion 20 are joined, the convex upper surface 105 is not exposed when viewed from above. Since the convex upper surface 105 is entirely joined to the second lower surface 204, the second lower surface 204 has a shape and area that can encompass the convex upper surface 105. Therefore, the area of the second lower surface 204 is larger than the area of the convex upper surface 105. The width of the second lower surface 204, in other words, the distance between the second inner surface 207 and the third inner surface 208 or the distance between the second inner surface 207 and the first inner surface 206 is the width of the convex upper surface 105. , in other words, is larger than the distance between the convex outer surface 106 and the convex inner surface 107.

Further, in a plane direction parallel to the first surface 101, the width of the convex upper surface 105 is smaller than the distance from the outer surface 103 of the base 10 to the third inner surface 208 of the frame section 20. Furthermore, in a region of the inner surface of the frame 20 that does not have the third inner surface 208, the width of the convex upper surface 105 is smaller than the distance from the outer surface 103 of the base 10 to the first inner surface 206 of the frame 20. small.

Since the base 10 has such a convex portion 104, the bonding stress between the frame and the base 10 is concentrated on the convex portion 104, and the convex portion 104 is deformed to absorb the stress. This makes it possible to suppress cracking, deformation, etc. due to stress when the base portion 10 and the frame portion 20, each made of materials having different coefficients of thermal expansion, are joined together.

Note that the coefficient of thermal expansion here particularly refers to the coefficient of linear expansion. The thermal expansion coefficient of the metal constituting the base 10 is in the range of 5.0 or more and 18.0 or less. Further, the thermal expansion coefficient of the ceramic forming the frame portion 20 is in the range of 2.0 or more and 8.0 or less. Further, the difference in thermal expansion coefficient between the base portion 10 and the frame portion 20 is in the range of 1.0 or more and 12.0 or less.

Note that as the metal forming the base portion 10 and the ceramic forming the frame portion 20, a material having a coefficient of thermal expansion outside the numerical range mentioned above may be used. Therefore, members having different coefficients of thermal expansion can be said to be members having a difference in coefficient of thermal expansion in a range of 0.5 or more and 15.0 or less, for example. Furthermore, in the temperature range from -40°C to 150°C, the difference in thermal expansion coefficients can be said to be members that are in the range of 0.5 or more and 15.0 or less.

Note that the frame 20 mainly made of alumina has a smaller difference in coefficient of thermal expansion from the base 10 mainly made of copper than the frame 20 mainly made of aluminum or the like, so it is less likely to crack or deform. It is effective in suppressing

In addition, since the convex portion 104 of the base 10 protrudes at a position apart from the outer surface of the base 10, the second inner surface 207 of the frame 20 and the outer surface 103 of the base 10 may be partially separated due to misalignment during mounting. Even if they do come into contact, contact between the convex outer surfaces 106 can be avoided. When the convex outer surface 106 contacts the second inner surface 207, the deformation of the convex portion 104 in response to stress is suppressed, reducing the stress absorption effect, but if they are separated from each other, this effect is eliminated.

The center of the width of the second lower surface 204 is included in the joining region where the convex upper surface 105 of the base 10 and the second lower surface 204 of the frame section 20 are joined. This makes it possible to balance the external force that the base 10 applies to the second lower surface 204 of the frame 20 due to temperature changes.

The convex inner surface 107 of the base 10 is closer to the outer surface 103 than the third inner surface 208 of the frame section 20 or the first inner surface 206 in a region that does not have the third inner surface 208 . That is, in the second lower surface 204, the end of the convex inner surface 107 is located at a position spaced apart from the third inner surface 208 or the end that intersects with the first inner surface 206 in a region not having the third inner surface 208. It joins with the lower surface 204. This makes it possible to balance the external force that the base 10 applies to the second lower surface 204 of the frame 20 due to temperature changes.

The second surface 102 of the base 10 and the first lower surface 203 of the frame 20 are arranged on the same plane. Note that implementation is based on designs arranged on the same plane, and any resulting errors are included in the interpretation of "on the same plane." In the light emitting device 1, if the distance between the plane having the second surface 102 of the base 10 and the plane having the first lower surface 203 of the frame part 20 is 0.1 mm or less, it is interpreted as "on the same plane". may be included in

The three semiconductor laser elements 30 are arranged on the first surface 101 of the base 10 via the submount 40. Furthermore, the submount 40 is provided separately for each semiconductor laser element 30. Note that a plurality of semiconductor laser elements 30 may be arranged on the upper surface of one submount 40. The base 10, which is mainly made of copper, has excellent thermal conductivity and can function as a heat dissipating member that effectively dissipates the heat generated by the semiconductor laser element 30.

The semiconductor laser element 30 placed on the base 10 is surrounded by the frame 20. Furthermore, the semiconductor laser element 30 disposed on the base 10 is located at a lower position than the first upper surface 201 of the frame 20. That is, the semiconductor laser element 30 is placed inside the cavity formed by the base 10 and the frame 20. In other words, it can be said that the cavity of the package in which the base portion 10 and the frame portion 20 are joined surrounds the semiconductor laser element 30.

The submount 40 is bonded to the first surface 101 of the base 10 at its lower surface, and to the semiconductor laser element 30 at its upper surface. The semiconductor laser element 30 is arranged so that the emission end face of the semiconductor laser element 30 is aligned with the side surface of the submount 40 or protrudes from it. By using the submount 40, the height from the first surface 101 to the light emission position of the semiconductor laser element 30 can be increased. Further, a protection element 70 is arranged on the upper surface of the submount 40.

Further, the submount 40 is designed so that the height from the first surface 101 is the same among the three semiconductor laser elements 30. Further, the emission end faces of each semiconductor laser element 30 are designed to be arranged on one virtual plane. Note that even if the designs are the same, errors occur due to component tolerances, mounting tolerances, etc. at the mounting stage. When the light emitting device 1 is said to have the same height, length, position, relative positional relationship, etc., it is assumed that such errors are included in the permissible range.

Note that the heights of the submounts 40 do not necessarily have to be the same among the three semiconductor laser elements 30. For example, if the light emitting points of three semiconductor laser elements 30 differ due to differences in mounting orientation, etc., the heights from the first surface 101 to the light emitting points can be made the same by using the submount 40. It is also conceivable to employ submounts 40 having different heights. It is also conceivable that the output end faces are arranged not on the same plane but on different parallel planes.

The light reflecting member 50 is arranged on the first surface 101 of the base 10. A light reflecting member 50 is separately arranged corresponding to each semiconductor laser element 30. Further, among the three semiconductor laser elements 30, the distance between the emission end face of each semiconductor laser element 30 and the corresponding light reflecting member 50 is designed to be the same. Note that one light reflecting member 50 may be arranged corresponding to a plurality of semiconductor laser elements 30.

Since the light emitted from the semiconductor laser element 30 has an elliptical FFP (far field pattern), by raising the emission position via the submount 40, more light is emitted from the semiconductor laser element 30. The light reflecting surface of the light reflecting member 50 can be irradiated with the light.

One ends of a plurality of wires are bonded to the metal film 209 provided on the second upper surface 202 of the frame portion 20 . The other ends of the plurality of wires are respectively bonded to the semiconductor laser element 30, the protection element 70, or the metal film 209 provided on the upper surface of the submount 40. Thereby, the semiconductor laser element 30 and the protection element 70 are electrically connected via the metal film 209 provided on the first lower surface 203 of the frame section 20.

Regarding the inner surface of the frame portion 20, the third inner surface 208 is not provided in a region opposite to and closest to the side surface that intersects with the upper surface of the light reflecting member 50 on the opposite side to the light reflecting surface. Therefore, the second upper surface 202 is also not provided in this area. This is because if the second upper surface 202 is provided in this area and the wire is stretched, the wire will straddle the light reflecting member 50 and become an obstacle on the optical path of the reflected light. Further, by not providing the third inner surface 208 over the entire circumference of the inner surface, the size of the light emitting device 1 can be reduced.

The lid member 80 is joined to the first upper surface 201 of the frame portion 20 at its lower surface. The lid member 80 and the frame portion 20 are provided with a metal film in the region where they are joined, and are fixed via Au--Sn or the like. Further, a closed space is formed by joining the frame portion 20 and the lid member 80. This closed space becomes an airtightly sealed space.

By airtightly sealing in this manner, it is possible to prevent organic matter and the like from collecting on the light emitting end face of the semiconductor laser element 30. Further, since the frame portion 20 mainly made of alumina and the lid member 80 mainly made of sapphire have a small difference in coefficient of thermal expansion, they are effective in suppressing cracking and deformation.

The reflected light reflected by the light reflecting surface of the light reflecting member 50 enters the lid member 80. The lid member 80 is designed so that at least a main portion of the area from when the reflected light enters until it exits is translucent. Here, being transparent means that the transmittance to light is 80% or more.

In the light emitting device 1, the metal film 209 provided on the first lower surface 203 of the frame portion 20 and the second surface 102 of the base portion 10 are joined to the substrate 2. Further, by bonding the metal film 209 provided on the first lower surface 203 of the frame portion 20 to the metal film of the substrate 2, electrical connection can be achieved via the metal film of the substrate 2. The light emitting device 1 and the substrate 2 can be joined by soldering.

According to the light emitting device 1 according to the first embodiment, the protrusions 104 provided on the base 10 absorb stress, thereby suppressing the occurrence of cracks, damage, peeling, etc. Further, it is possible to suppress the occurrence of cracking, damage, peeling, etc. in a package in which at least the base portion 10 and the frame portion 20 are joined and a light emitting element such as the semiconductor laser element 30 is mounted.

Hereinafter, a base 10 having a different shape from the base 10 employed in the light emitting device 1 of the first embodiment will be described. Even if the base 10 is as shown below, it can be joined to the frame 20 to form a package.

<Second embodiment>
FIG. 11 is a sectional view for explaining the shapes of the base 10 and the frame 20 of the light emitting device according to the second embodiment. Note that the position of the cross section is the same as the line IX-IX in FIG. The light emitting device according to the second embodiment differs from the light emitting device according to the first embodiment in the shape of the base. Specifically, the base 10A in FIG. 11 differs from the first embodiment in that it has a recess 108 between the second surface 102 and the outer surface 103 on the second surface 102 side of the base 10. It is different from the base 10.

The recess 108 of the base 10A has a distance from the second inner surface 207 of the frame 20 that is larger than the distance from the outer surface 103 of the base 10A. established for the purpose of Therefore, the recessed portion 108 is recessed from the second surface 102 of the base 10 toward the first surface 101 side. Even if the second inner surface 207 and the outer surface 103 come into contact as a result of a deviation from the designed positional relationship in joining the base 10A and the frame 20, the provision of the recess 108 allows the second inner surface 207 of the base 10A to It is possible to prevent the surface 102 from being electrically connected to the metal film of the substrate 2.

<Third embodiment>
FIG. 12 is a sectional view for explaining the shapes of the base 10 and the frame 20 of the light emitting device according to the third embodiment. Note that the position of the cross section is the same as the line IX-IX in FIG. The light emitting device according to the third embodiment differs from the light emitting device according to the first embodiment in the shape of the base. Specifically, the base 10B of FIG. 12 differs from the base 10 of the first embodiment in the position where the convex portion 104 is provided on the first surface 101 side of the base 10.

In the base 10B according to the third embodiment, a convex portion 104 is provided without being separated from the outer surface 103. In other words, the convex outer surface 106 of the convex portion 104 and the outer surface 103 of the base portion 10B are formed by one side surface, and the outer convex surface 103 of the base portion 10B also serves as the convex outer surface 106 of the convex portion 104. Even with such a shape, stress can be absorbed by the convex portion 104 provided on the base 10, similar to the base 10 of the first embodiment.

<Fourth embodiment>
FIG. 13 is a cross-sectional view for explaining the shapes of the base 10 and the frame 20 of the light emitting device according to the fourth embodiment. Note that the position of the cross section is the same as the line IX-IX in FIG. The light emitting device according to the fourth embodiment differs from the light emitting device according to the first embodiment in the shape of the base. Specifically, the base 10C in FIG. 14 has a shape that combines the differences between the second embodiment and the third embodiment with respect to the base 10 of the first embodiment. That is, the recess 108 is provided on the second surface 102 side, and the protrusion 104 is provided on the first surface 101 side without being separated from the outer surface 103.

Although the present invention has been described above based on each embodiment, the structure of a light emitting device to which the present invention is applied is not limited to that of the embodiments. For example, although a light emitting device in which three semiconductor laser elements are arranged has been described, a light emitting device in which one or more semiconductor laser elements are arranged may be used. Alternatively, the light emitting device may have no light reflecting member and the light emitted from the semiconductor laser element passes through the lid member.

That is, the light emitting device to which the present invention is applied may have, for example, components not disclosed in the light emitting device of the embodiment. Conversely, some of the components disclosed in the light emitting device of the embodiment may not be included. Just because there is a difference from the light emitting device of the embodiment does not mean that the present invention cannot be applied.

For example, if some components of the light emitting device disclosed in the first embodiment are not described in the claims, those components may be replaced with the disclosure in the first embodiment. This allows for freedom in design by those skilled in the art, such as omission, modification of shape, change of material, etc., and claims that the invention described in the claims is applied based on this.

The light emitting device described in each embodiment can be used for a projector, a vehicle headlight, a lighting device, a display, and the like.

1 Light-emitting device 10, 10A, 10B, 10C Base 101 First surface 102 Second surface 103 Outer surface 104 Convex portion 105 Convex upper surface 106 Convex outer surface 107 Convex inner surface 108 Recessed portion 20 Frame portion 201 First upper surface 202 Second upper surface 203 First lower surface 204 Second lower surface 205 Outer surface 206 First inner surface 207 Second inner surface 208 Third inner surface 209 Metal film 30 Semiconductor laser element 40 Submount 50 Light reflecting member 70 Protective element
80 Lid member

2 Board

Claims (10)

a first semiconductor laser element;
a light reflecting member having a light reflecting surface that reflects light emitted from the first semiconductor laser element;
a first surface where the first semiconductor laser element and the light reflecting member are arranged; and a convex formed on the side of the first surface outside a region where the first semiconductor laser element and the light reflecting member are arranged. a base having a portion;
The first semiconductor laser is mainly made of a material having a coefficient of thermal expansion different from that of the main material used for the base, has a joint surface that joins with the protruding upper surface of the convex part of the base, and is disposed on the first surface. a frame portion surrounding the element and the light reflecting member;
has
The first semiconductor laser element and the light reflecting member are arranged in a hermetically sealed space. The light emitting device according to claim 1, wherein the joint surface of the frame is a second lower surface formed between a first upper surface that intersects with an outer surface of the frame and a first lower surface. The frame has a first inner surface on the side of the first upper surface of the frame, and a first inner surface on the side of the first lower surface of the frame, and at least a portion thereof is closer to the outer surface than the first inner surface. a second inner surface located at
The light emitting device according to claim 2, wherein the joint surface of the frame portion is at least partially the second lower surface extending from the second inner surface side to the first inner surface side. The frame portion includes a second upper surface that extends inward from at least a portion of the first inner surface between the first upper surface and the first lower surface of the frame portion, and a second upper surface that extends inward from the first inner surface of at least a portion of the first inner surface, and a second upper surface that extends between the second upper surface and the second lower surface. a third inner surface formed inside the first inner surface;
4. The light emitting device according to claim 3, further comprising a metal film electrically connected to the first semiconductor laser element on at least a portion of the second upper surface of the frame. 1 . The base has the convex portion that protrudes on the first surface side at a position spaced apart from a position where it intersects with the outer surface of the base, and the protruding upper surface is formed inward from the protruding position. 5. The light emitting device according to any one of 4 to 5. The light emitting device according to any one of claims 1 to 4, wherein the protruding upper surface of the convex portion intersects with the outer surface of the base on the first surface side of the base. The light emitting device according to any one of claims 1 to 6, wherein the area of the protruding upper surface of the base is smaller than the area of the joint surface of the frame. The base includes a second surface on the opposite side to the first surface, and a recessed portion that intersects with the second surface and the outer surface of the base and is recessed from the second surface toward the first surface; The light emitting device according to any one of claims 1 to 7, comprising: The light emitting device according to any one of claims 1 to 8, wherein the main material of the base is metal, and the main material of the frame is ceramic. The light emitting device according to any one of claims 1 to 4, further comprising a second semiconductor laser element disposed on the first surface.

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