Light-emitting device

Abstract

The light-emitting device includes a main body and a lens array, wherein the main body has a semiconductor laser element mounted in an internal space and is made of metal, and the lens array is bonded to the main body via a base connection layer and a connection layer containing solder to airtightly seal the internal space, wherein the base connection layer is made of a metal having a thermal expansion coefficient between the thermal expansion coefficient of the lens array and the thermal expansion coefficient of the metal constituting the main body.

Description

Technical Field

[0001] The present invention relates to a light emitting device. Background Art

[0002] A light emitting device using a semiconductor laser element as a light emitting element for emitting laser light is known. Such a light emitting device requires a light-transmitting window for extracting the laser light and hermetically sealing the semiconductor laser element.

[0003] Japanese Patent Application Laid-Open No. 2005-101481 discloses a semiconductor device cover in which a light-transmitting window is sealed in a cover body made of metal using low-melting-point glass as a sealing material, and the cover can be applied to such a light-emitting device. Summary of the Invention

[0004] Technical problems to be solved by the present invention

[0005] However, while this prior art is suitable for bonding a light-transmitting window to a semiconductor device cover, it is not suitable for sealing a light-transmitting window to a light-emitting device package. To improve heat dissipation within the package, when the package is primarily made of copper (Cu), the thermal expansion coefficient difference between the package and the glass light-transmitting window (sealing glass) is significant, leading to the risk of damage to the light-transmitting window due to thermal stress.

[0006] One aspect of the present invention has been made in view of the above-mentioned conventional problems, and its purpose is to realize a light-emitting device in which the main body of the light-emitting device can be sealed by the sealing glass without breaking the sealing glass even when there is a large difference in thermal expansion between the main body of the light-emitting device and the sealing glass.

[0007] Technical solutions to technical problems

[0008] In order to solve the above-mentioned problems, a light-emitting device involved in one embodiment of the present invention includes: a main body, which is made of metal and has an internal space and an opening portion that passes through the internal space and the outside, and at least one semiconductor laser element is mounted in the internal space; and a sealing glass is bonded to the main body in a manner that covers the opening portion and hermetically seals the internal space of the main body. On the surface of the sealing glass on the main body side, a base connection layer is provided in the bonding area between the sealing glass and the main body, and the base connection layer is made of a metal having a thermal expansion coefficient between the thermal expansion coefficient of the sealing glass and the thermal expansion coefficient of the metal constituting the main body. The sealing glass is bonded to the main body via the base connection layer and the connection layer containing solder.

[0009] Furthermore, a method for manufacturing a light-emitting device according to one embodiment of the present invention is characterized in that the light-emitting device has a main body portion, which is made of metal and has an internal space and an opening portion that passes through the internal space and the outside, and at least one semiconductor laser element is mounted in the internal space. The manufacturing method is a method for manufacturing a light-emitting device in which a sealing glass is bonded to the main body portion so as to cover the opening portion, thereby airtightly sealing the internal space of the main body portion, and a bonding area between the sealing glass and the main body portion is pre-patterned on a surface of the sealing glass on the main body side. a base layer and a solder layer on the base layer, the base layer being composed of a metal having a thermal expansion coefficient between the thermal expansion coefficient of the sealing glass and the thermal expansion coefficient of the metal constituting the main body, and including a close-fitting layer formed on the surface of the sealing glass, a barrier layer on the close-fitting layer, and a connecting metal layer on the barrier layer, the surface of at least the bonding area of ​​the main body being pre-covered with a gold layer, and the bonding of the sealing glass to the main body being performed as follows: the bonding area is heated, and alloying is performed between the connecting metal layer and the solder layer, and between the solder layer and the gold layer.

[0010] Beneficial effects

[0011] According to one aspect of the present invention, a light emitting device is realized in which the light emitting device body can be sealed by the sealing glass without breaking the sealing glass even when there is a large difference in thermal expansion between the main body of the light emitting device and the sealing glass. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a cross-sectional view schematically showing an example of a general configuration of a light-emitting device according to Embodiment 1 of the present invention.

[0013] Figure 2 It is a perspective view schematically showing an example of the general configuration of the light emitting device.

[0014] Figure 3 This is a cross-sectional view schematically showing the structure of a base layer and a solder layer before alloying in the bonding region of the light-emitting device.

[0015] Figure 4 The diagram is a cross-sectional view illustrating steps of an example of a method for manufacturing the light-emitting device.

[0016] Figure 5 It is an explanation Figure 4 A cross-sectional view of a subsequent step of an example of the method for manufacturing the light-emitting device.

[0017] Figure 6 It is an explanation Figure 5A cross-sectional view of a subsequent step of an example of the method for manufacturing the light-emitting device.

[0018] Figure 7 It is an explanation Figure 6 A cross-sectional view of a subsequent step of an example of the method for manufacturing the light-emitting device.

[0019] Figure 8 This is a cross-sectional view schematically showing an example of a general configuration of a light-emitting device according to Embodiment 2 of the present invention.

[0020] Figure 9 This is a partially enlarged cross-sectional view schematically showing an example of the general configuration of a light-emitting device according to Embodiment 3 of the present invention.

[0021] Figure 10 It is a diagram for explaining the effect of the groove. The enlarged view 1001 is a diagram for explaining the stress of the solder layer on the lens array when the groove is not formed. The enlarged view 1002 is a diagram for explaining the stress on the lens array when the groove is formed. DETAILED DESCRIPTION

[0022] [Implementation Method 1]

[0023] In the currently circulating butterfly-shaped MCP (Multi Chip Package), the internal space of the light-emitting device body is hermetically sealed using a sealing member (cover glass, etc.), and the lens array is fixed to the sealing member using an adhesive.

[0024] In contrast, one embodiment of the present invention uses lens array 20, rather than a sealing component, to hermetically seal the interior space 11 of the main body 10 of the light-emitting device 100. This eliminates the need for space for sealing components other than the lens array 20. Furthermore, since the number of sealing components can be reduced, a manufacturing step can be eliminated.

[0025] However, when the internal space 11 of the main body 10 is hermetically sealed by the lens array 20, the following problems arise. For example, if the main body 10 is made of copper, the thermal expansion coefficient is 17.7×10 -6 [1 / K], the thermal expansion coefficient of the lens array 20 (glass) is 7.2×10 -6 [1 / K], thus increasing the thermal expansion difference. Therefore, if the lens array 20 is directly sealed to the main body 10 using only the solder layer 40, the lens array 20 is directly subjected to thermal stress caused by the thermal expansion difference between the main body 10 and the lens array 20. As a result, there is a risk of damage to the lens array 20.

[0026] Therefore, one embodiment of the present invention has the following structure, so that even if the thermal expansion difference between the main body 10 and the lens array 20 is large, the main body 10 can be hermetically sealed with the lens array 20. That is, the light-emitting device 100 involved in one embodiment of the present invention has a base layer 30 composed of metal between the lens array 20 and the solder layer 40, and the metal has a thermal expansion coefficient between the thermal expansion coefficient of the metal constituting the main body 10 and the thermal expansion coefficient of the lens array 20. As a result, the thermal stress caused by the thermal expansion difference between the main body 10 and the lens array 20 can be alleviated, and the risk of damage to the lens array 20 can be reduced. The following will be described in detail.

[0027] (Light-emitting device)

[0028] based on Figure 1 as well as Figure 2 An embodiment of the present invention will be described in detail. Figure 1 This is a cross-sectional view schematically showing an example of the general configuration of the light emitting device 100 according to the first embodiment of the present invention. Figure 2 It is a perspective view showing an example of a schematic structure of the light emitting device 100 .

[0029] in addition, Figure 1 The cross-sectional view is a cross-sectional view taken along a plane parallel to the emission direction D of the light emitted from the light emitting device 100 to the outside, and the position of the cross-sectional view is set so that the connection state of the wire to the semiconductor laser element 1 can be confirmed. Figures 4 to 9 The same is true. The surface parallel to the emission direction D of the emitted light emitted from the light emitting device 100 to the outside is a heat dissipation surface for dissipating heat generated by the semiconductor laser element 1, that is, a surface parallel to the bottom surface 14 of the main body 10. In order to easily understand the interior of the internal space 11 of the main body 10, Figure 2 In this diagram, a portion of the main body 10 located above the internal space 11 and a portion located in front of the internal space 11 are shown transparently.

[0030] Light-emitting device 100 includes multiple semiconductor laser elements 1. Light emitted from these multiple semiconductor laser elements 1 is separated into individual collimated beams by lens array 20 and ultimately focused into a single laser beam by a lens on the device equipped with light-emitting device 100. Light-emitting device 100 can be used in devices requiring peak output, such as projectors, indoor and outdoor lighting, automotive headlights, and searchlights.

[0031] like Figure 1 as well as Figure 2 As shown, the light emitting device 100 includes a main body 10 and a lens array 20 , and the main body 10 and the lens array 20 are bonded together via a bonding region 50 between the main body 10 and the lens array 20 .

[0032] (Main body)

[0033] The main body 10 is a roughly rectangular shell made of metal, and an internal space 11 is formed inside the shell. In the main body 10, an opening 13 is formed on an exit surface (outer surface) 12 located in the exit direction D of the exit light emitted from the main body 10 to the outside, so as to penetrate the internal space 11 and the outside. The opening area of ​​the opening 13 is preferably a size that most of the exit light from the semiconductor laser element 1 provided in the main body 10 passes through. The shape of the opening 13 is not particularly limited. In this embodiment, the shape of the opening 13 is roughly rectangular. In addition, as Figure 2 As shown, a positioning hole 15a and a positioning hole 15b for positioning may also be formed in the main body 10. The positioning hole 15a is a through hole that passes through the main body 10 in a direction substantially parallel to the emission direction D, and the positioning hole 15b is a through hole that passes through the main body 10 in a manner perpendicular to the positioning hole 15a and the main body bottom surface 14.

[0034] Main body 10 is preferably composed of a metal primarily composed of copper (Cu). In this application, "primary component" means an atomic composition percentage of 50 at% or greater. This allows efficient dissipation of heat generated by semiconductor laser element 1 from main body bottom surface 14 to the outside. Main body 10 is plated (electroplated) with a metal containing, for example, gold (Au) (not shown).

[0035] The main body 10 has a plurality of semiconductor laser elements 1 mounted in an internal space 11 . The number of semiconductor laser elements 1 is not limited to the example shown in the figure, and at least one semiconductor laser element 1 may be mounted in the internal space 11 .

[0036] Semiconductor laser element 1 emits laser light as outgoing light. In this embodiment, outgoing light is emitted from semiconductor laser element 1 in an outgoing direction D that is substantially parallel to the layers of the stacked structure of semiconductor laser element 1. The outgoing light is then emitted from main body 10 to the outside in outgoing direction D via lens array 20 (described later).

[0037] Furthermore, the emission direction of the light emitted from the semiconductor laser element 1 and the emission direction of the light emitted from the main body 10 to the outside do not need to be the same. Alternatively, the light emitted from the semiconductor laser element 1 may be reflected using a reflector or the like, thereby causing the light to be emitted from the main body 10 to the outside in the direction of the stacking of the semiconductor laser elements 1. Thus, one embodiment of the present invention can also be applied to butterfly-type MCPs.

[0038] More specifically, the semiconductor laser element 1 is mounted in the internal space 11 of the main body 10 as follows. For example, during the cutting process of the main body 10, the base portion 3 is integrally formed with the main body 10. Furthermore, the semiconductor laser element 1 is mounted on the base 2, which is an insulator, and the base 2 is bonded to the base 3. Thus, the semiconductor laser element 1 is mounted in the internal space 11 of the main body 10. Furthermore, heat generated in the semiconductor laser element 1 can be efficiently dissipated from the base 2 to the outside via the main body 10.

[0039] Multiple semiconductor laser elements 1 are arranged in a straight line on the main body 10. Adjacent semiconductor laser elements 1 are electrically connected via a base 2 via wires 5. Furthermore, the semiconductor laser elements 1 at both ends are electrically connected to pins 4 via wires 5. Pins 4 are terminals for electrically connecting the semiconductor laser elements 1 to the outside of the light-emitting device 100. Pins 4 are insulated from the main body 10 by being fixed to the main body 10, for example, using an airtight seal.

[0040] The lens array 20 (sealing glass) is bonded to the main body 10 via a base layer 30 and a solder layer 40 (described later) so as to cover the opening 13, thereby airtightly sealing the interior space 11 of the main body 10. The lens array 20 is larger than the opening 13, so that the lens array 20 can cover the opening 13.

[0041] The lens array 20 includes the same number of lens portions 21 as the number of semiconductor laser elements 1, and connecting portions 22 located around the lens portions 21. The lens array 20 includes the lens portions 21 at positions where light emitted from the semiconductor laser elements 1 passes. The plurality of lens portions 21 are formed continuously on a straight line, and the lens portions 21 and connecting portions 22 are integrally formed.

[0042] The shape of the lens portion 21 is not particularly limited, but has a shape capable of parallelizing (collimating) the laser beams incident from the semiconductor laser elements 1. The lens array 20 can be formed using a light-transmitting material such as glass or synthetic quartz.

[0043] (bonding area)

[0044] The bonding area 50 is an area where the base connection layer 30X and the connection layer 40X are formed to bond the main body 10 to the lens array 20. The bonding area 50 is formed on the surface 23 of the lens array 20, along the outer edge of the lens array 20, at a position corresponding to the periphery of the opening forming the opening portion 13. The bonding area 50 is formed on the exit surface 12 on the main body 10 side, along the periphery of the opening forming the opening portion 13, at a position corresponding to the outer edge of the lens array 20.

[0045] In the bonding region 50, the base layer 30, solder layer 40, and gold plating of the main body 10 (described later) are heated, partially mixing and alloying them, thereby bonding the main body 10 to the lens array 20. This alloying can be, for example, eutecticization. The base connection layer 30X and the connection layer 40X are formed in the heated bonding region 50.

[0046] Here, the base connection layer 30X refers to a base layer 30 in which a portion of the base layer 30 is integrally connected to the solder layer 40 and becomes inseparable due to the alloying performed in the base layer 30 described later. Furthermore, the connection layer 40X refers to a solder layer 40 in which a portion of the base layer 30 is integrally connected to the solder layer 40 and becomes inseparable due to the alloying performed in the solder layer 40 described later. Details will be described later.

[0047] (Base layer and base connection layer)

[0048] The base connection layer 30X is made of a metal having a thermal expansion coefficient between that of the lens array 20 and that of the metal constituting the main body 10. In the bonding region 50 between the main body 10 and the lens array 20, the base connection layer 30X is provided along the outer edge of the lens array 20 on the main body 10 side surface 23. In other words, the base connection layer 30X is provided on the surface 23 of the lens array 20 at a position corresponding to the periphery of the opening 13.

[0049] Before alloying, Figure 3 As shown, the base connecting layer 30X serves as the base layer 30, and has a close-fitting layer 31, a barrier layer 32 and a connecting metal layer 33, which are stacked in sequence in the direction away from the lens array 20 in the order of the close-fitting layer 31, the barrier layer 32 and the connecting metal layer 33. Figure 3 This is a cross-sectional view schematically showing the structure of the base layer 30 and the solder layer 40 before alloying is performed in the bonding region of the light emitting device 100 .

[0050] The adhesion layer 31 is formed on the surface 23 of the lens array 20 and is a layer made of metal for adhering the lens array 20 to the base layer 30. As the adhesion layer 31, for example, a metal mainly composed of chromium (Cr) or titanium (Ti) can be used. The thermal expansion coefficient of chromium is 11.3×10 -6 [1 / K] is the difference between the thermal expansion coefficient of copper, which is a main component of the main body 10 of the present embodiment, and the thermal expansion coefficient of glass, which is a main component of the lens array 20 .

[0051] The barrier layer 32 is formed on the adhesion layer 31 between the adhesion layer 31 and the connecting metal layer 33. It is a layer composed of metal and is used to prevent the adhesion layer 31 from mixing with the solder layer 40 during alloying. This can maintain close contact between the base layer 30 and the lens array 20, so that the main body 10 can be reliably sealed using the lens array 20.

[0052] As the barrier layer 32, for example, a metal containing platinum (Pt) as a main component can be used. The thermal expansion coefficient of platinum is 8.8×10 -6 [1 / K], is the coefficient of thermal expansion between the thermal expansion coefficient of copper and the thermal expansion coefficient of glass.

[0053] The connection metal layer 33 is a layer made of metal for alloying the solder layer 40 with at least a portion of the connection metal layer 33 by heating. For example, a metal containing gold as a main component can be used as the connection metal layer 33. The thermal expansion coefficient of gold is 14.2×10 -6 [1 / K], is the coefficient of thermal expansion between the thermal expansion coefficient of copper and the thermal expansion coefficient of glass.

[0054] After the base layer 30 is heated and alloyed with the solder layer 40, the adhesion layer 31 and the barrier layer 32 can be identified as separate layers. However, the connection metal layer 33 is sometimes not separately identified because it is integrated with the solder layer 40. In this embodiment, the alloyed base layer 30 is used as the base connection layer 30X.

[0055] (Solder layer and connection layer)

[0056] The connection layer 40X is a layer formed by alloying at least a portion of the solder layer 40 with a portion of the base layer 30 and at least a portion of the solder layer 40 with a portion of the plating layer of the main body 10 by heating. The connection layer 40X bonds the main body 10 to the lens array 20. The solder layer 40 contains solder and is composed of a metal having, for example, gold, gold and tin (Sn), or tin, silver (Ag), and copper as a main component. The thermal expansion coefficient of gold is 14.2×10 -6 [1 / K], is the coefficient of thermal expansion between the thermal expansion coefficient of copper and the thermal expansion coefficient of glass.

[0057] When the solder layer 40 is heated and alloyed with the connecting metal layer 33, the connecting metal layer 33 and the solder layer 40 may become integrated and cannot be distinguished separately. In this embodiment, the alloyed solder layer 40 is used as the connecting layer 40X. The base layer 30 and the solder layer 40 before alloying become the base connecting layer 30X and the connecting layer 40X after alloying, and the main body 10 and the lens array 20 are bonded in the bonding area 50.

[0058] (Examples of materials and thickness of each layer)

[0059] When the main component of the main body 10 is copper, the material and thickness of each layer can be, for example, as follows. A metal with chromium as the main component is used as the adhesion layer 31, and the thickness of the adhesion layer 31 is set to be greater than 0.1 μm. A metal with platinum as the main component is used as the barrier layer 32, and the thickness of the barrier layer 32 is set to be greater than 0.2 μm. A metal with gold as the main component is used as the connection metal layer 33, and the thickness of the connection metal layer 33 is set to be greater than 0.5 μm. A metal containing gold-tin is used as the solder layer 40, and the thickness of the solder layer 40 is set to be greater than 15 μm. In addition, gold plating (gold layer) of several μm is implemented on the main body 10.

[0060] (Method for manufacturing light-emitting device)

[0061] based on Figures 4 to 7 , a method for manufacturing the light-emitting device 100 is described. Figure 4 These are cross-sectional views illustrating steps of an example method of manufacturing the light emitting device 100 . Figures 5 to 8 Each of them is a subsequent cross-sectional view of the previous figure.

[0062] First, at least one semiconductor laser element 1 is mounted in the interior space 11 of the main body 10 (mounting step). The main body 10 is formed of metal and has an interior space 11 and an opening 13 that connects the interior space 11 to the exterior. The mounting step is performed with the leads 4 positioned in the main body 10, which is previously plated with gold.

[0063] Specifically, multiple semiconductor laser elements 1, which have been pre-mounted on base 2, are mounted on base 3 integrally formed with main body 10, thereby mounting multiple semiconductor laser elements 1 on main body 10. The height of base 3 from main body bottom surface 14 is designed so that most of the light emitted from semiconductor laser elements 1 mounted on main body 10 passes through opening 13, and base 3 is formed on main body 10.

[0064] Then, if Figure 5 As shown, each semiconductor laser element 1 and lead 4 are electrically connected via a wire 5 .

[0065] As shown in the figure, a base layer 30 with a pre-patterned bonding area 50 between the lens array 20 and the main body 10 and a solder layer 40 are formed on the base layer 30 on the surface 23 of the lens array 20 on the main body 10 side (base layer formation step). Specifically, a close-fitting layer 31 is formed on the surface 23 of the lens array 20, a barrier layer 32 is formed on the close-fitting layer 31, and a connecting metal layer 33 is formed on the barrier layer 32, thereby forming the base layer 30. The solder layer 40 is formed on the connecting metal layer 33.

[0066] The base layer 30 and the solder layer 40 may both be provided on the main body 10 side, or only the solder layer 40 may be provided on the main body 10. The base layer 30 may be provided on the lens array 20 side between the lens array 20 and the main body 10, and the solder layer 40 may be provided on the main body 10 side.

[0067] Then, if Figure 6 As shown, the lens array 20 is positioned relative to the main body 10 in a manner that the lens portion 21 is fixed at a position where the emitted light of each semiconductor laser element 1 passes, and the bonding area 50 is heated. The above-mentioned heating method is not particularly specified, and it is possible to heat only the base layer 30 and the solder layer 40, or to heat the entire light-emitting device 100. Specifically, the heating method includes, for example, the following methods (1) and (2). (1) A method of heating the main body 10 to the melting point of the solder layer 40. In this case, the heating is performed and the lens array 20 at room temperature is mounted on the main body 10. (2) A method of irradiating the bonding area 50 with a high-output laser in a point shape from the outside while the lens array 20 is mounted on the main body 10, and heating only the bonding area 50.

[0068] By heating, alloying is performed between the connection metal layer 33 and the solder layer 40 and between the solder layer 40 and the gold layer, and the lens array 20 is bonded to the main body 10 in the bonding area 50. Figure 7 As shown, a base connection layer 30X and a connection layer 40X are formed in the bonding area 50 between the main body 10 and the lens array 20. As a result, the lens array 20 is bonded to the main body 10 in a manner covering the opening 13, and the internal space 11 of the main body 10 is hermetically sealed by the lens array 20 (hermetic sealing step), thereby completing the light-emitting device 100.

[0069] (Implementation Method 2)

[0070] Hereinafter, a second embodiment of the present invention will be described. For the sake of convenience, components having the same functions as those described in the above embodiment are denoted by the same reference numerals, and their description will not be repeated.

[0071] Figure 8 1 is a cross-sectional view schematically showing an example of the general configuration of the light emitting device 101 according to the second embodiment of the present invention. Figure 8 , for ease of explanation, the diagram shows the state before the main body 10 and the lens array 20 are bonded together. In reality, the lens array 20 is moved in the direction of the arrow and placed on the main body 10. In the bonding area 50, a portion of the base layer 30 and at least a portion of the solder layer 40 are alloyed, forming the light emitting device 101. Figure 9 The same is true. Figure 8As shown, the light emitting device 101 is different from the light emitting device 100 in that the main body 10 is provided with a counterbore portion 16 , and the other structures are the same.

[0072] The main body 10 has a countersunk portion 16 formed around the opening 13 on the exit surface 12. The countersunk portion 16 is recessed relative to the exit surface 12, and the bottom surface 16a of the countersunk portion 16 is substantially parallel to the exit surface 12. The lens array 20 is bonded to the main body 10 on the bottom surface 16a of the countersunk portion 16.

[0073] Thus, by forming the countersunk portion 16 with the positioning of the lens array 20 in mind, the lens array 20 can be bonded to the countersunk portion 16 to hermetically seal the main body 10. This facilitates positioning of the lens array 20 when sealing the main body 10. Furthermore, the thickness of the light-emitting device 101 relative to the direction D of light emission from the semiconductor laser element 1 can be reduced, thereby making the light-emitting device 101 smaller.

[0074] [Third embodiment]

[0075] Hereinafter, a third embodiment of the present invention will be described. The third embodiment is an example of a modification of the second embodiment. Figure 9 : is a partially enlarged cross-sectional view schematically showing an example of the general configuration of the light emitting device 102 according to Embodiment 3 of the present invention. Specifically, Figure 9 It will be with Figure 8 The enlarged view of the part corresponding to the single-dot chain line Y. Figure 9 As shown, the light emitting device 102 is different from the light emitting device 101 in that the countersunk portion 16 of the main body 10 further includes a groove 17 , and the other structures are the same.

[0076] The countersunk portion 16 has a groove 17 formed along its periphery. The groove 17 is deeper than the bottom surface 16a of the countersunk portion 16. In other words, the groove 17 is formed between the countersunk portion 16 and the main body 10, and is recessed in a direction opposite to the emission direction D of the light emitted by the semiconductor laser element 1.

[0077] Figure 10 These are diagrams for explaining the effects of the grooves 17. Enlarged view 1001 illustrates the stress H in the solder layer 40 applied to the lens array 20 when the grooves 17 are not formed, and enlarged view 1002 illustrates the stress H in the solder layer 40 applied to the lens array 20 when the grooves 17 are formed.

[0078] The bonding between the main body 10 and the lens array 20 is a wide-range bonding due to alloying. Therefore, the thicker the base layer 30 and the solder layer 40 are, the more they can absorb the warpage of each component and the roughness of the bonding surface, thereby achieving stable bonding.

[0079] On the other hand, in a simple countersunk structure, as shown in the enlarged view 1001 , the thicker the base layer 30 and the solder layer 40 are, the greater the concern about creep R of the solder between the lens array 20 and the main body 10 when the main body 10 and the lens array 20 are bonded together.

[0080] If creep R occurs, the space between the lens array 20 and the main body 10 is filled with creep R. As a result, not only does the bottom surface of the lens array 20 bear stress H caused by the heat of the heated bonding area 50 cooling down and causing the main body 10 to shrink, but the side surfaces of the lens array 20 between the lens array 20 and the main body 10 also bear stress H, making the lens array 20 more susceptible to cracking.

[0081] In contrast, if groove 17 is provided, as shown in enlarged view 1002 , solder layer 40 accumulates in groove 17 , thus preventing creep R. Therefore, the stress H during contraction of body 10 is only affected by the bottom surface of lens array 20 , reducing the risk of damage to lens array 20 .

[0082] 〔Summarize〕

[0083] The light-emitting device (100, 101, 102) involved in mode 1 of the present invention comprises: a main body (10), which is made of metal and forms an internal space (11) and an opening (13) passing through the internal space and the outside, and at least one semiconductor laser element (1) is mounted in the internal space; and a sealing glass (lens array 20) is bonded to the main body in a manner covering the opening, and the internal space of the main body is airtightly sealed. On the surface of the sealing glass on the side of the main body, a base connection layer (30X) is provided in the bonding area (50) between the sealing glass and the main body, and the base connection layer (30X) is made of a metal having a thermal expansion coefficient between the thermal expansion coefficient of the sealing glass and the thermal expansion coefficient of the metal constituting the main body, and the sealing glass is bonded to the main body via the base connection layer and a connection layer (40X) containing solder.

[0084] According to the above structure, a base connection layer is provided on the surface of the main body side of the sealing glass. The sealing glass is bonded to cover the opening of the main body via the base connection layer and the connection layer containing solder, thereby hermetically sealing the internal space of the main body.

[0085] Furthermore, the base connection layer is composed of a metal having a thermal expansion coefficient intermediate between that of the lens array seal and that of the metal constituting the main body. Therefore, when the sealing glass and the main body are heat-bonded, the base connection layer mitigates the thermal stress caused by the thermal expansion difference between the sealing glass and the main body. As a result, even when the thermal expansion difference between the sealing glass and the main body of the light-emitting device is large, the sealing glass can be protected from damage and the interior space of the main body of the light-emitting device can be sealed.

[0086] In the light emitting device (100, 101, 102) of aspect 2 of the present invention, in the above aspect 1, the sealing glass (lens array 20) may have a lens portion at a position where the emitted light of the semiconductor laser element (1) passes.

[0087] According to the above structure, the main body can be sealed by the lens array, so there is no need to consider the installation location of the sealed lens array. In addition, there is no need to provide a separate sealing member, which can reduce the number of sealing members.

[0088] In the light-emitting device (100, 101, 102) of mode 3 of the present invention in the above-mentioned mode 1 or 2, the base connecting layer (30X) may also have a close-fitting layer (31) formed on the surface of the sealing glass (lens array 20), and a blocking layer (32) formed on the close-fitting layer.

[0089] According to the above structure, by appropriately selecting the material of the barrier layer, the barrier layer can prevent the solder layer from mixing with the adhesion layer when the sealing glass and the main body are heat-bonded. As a result, close contact between the base connection layer and the sealing glass can be maintained, and the main body can be reliably sealed by the sealing glass.

[0090] In the light-emitting device (100, 101, 102) of the fourth aspect of the present invention, in the third aspect, the adhesion layer (31) may be made of a metal having chromium or titanium as a main component, and the barrier layer (32) may be made of a metal having platinum as a main component. With the above-mentioned configuration, the adhesion layer and the barrier layer can be appropriately used as both the adhesion layer and the base layer.

[0091] The light-emitting device (101) involved in mode 5 of the present invention may also be provided with a countersunk portion (16) around the opening portion (13) on the outer side surface (exit surface 12) of the main body (10) in any of the above modes 1 to 4, and the sealing glass (lens array 20) is bonded to the above main body at the bottom surface (16a) of the countersunk portion.

[0092] According to the above configuration, the internal space of the main body can be sealed by bonding the sealing glass to the bottom surface of the countersunk portion, thereby facilitating positioning of the sealing glass. Furthermore, the semiconductor laser element of the light emitting device can be made thinner, thereby making the light emitting device smaller.

[0093] In the light emitting device (102) of mode 6 of the present invention in the above-mentioned mode 5, a groove (17) deeper than the bottom surface (16a) of the countersinking portion (16) may be provided along the periphery of the countersinking portion.

[0094] According to the above structure, creeping of the solder layer between the main body and the sealing glass can be prevented during sealing, thereby preventing the sealing glass from receiving stress from the side during sealing, thereby further reducing the risk of breakage of the sealing glass.

[0095] In the light emitting device (100, 101, 102) of mode 7 of the present invention, in any of the above modes 1 to 6, a plurality of the semiconductor laser elements (1) may be mounted in the internal space (11) of the main body (10).

[0096] According to the above configuration, even in a light emitting device equipped with a plurality of semiconductor laser elements, it is possible to realize a light emitting device in which the main body of the light emitting device is sealed with the sealing glass without damaging the sealing glass.

[0097] In the light-emitting device (100, 101, 102) according to aspect 8 of the present invention, in any of aspects 1 to 7, the connection layer (40X) may be composed of a metal having gold, gold and tin, or tin, silver, and copper as a main component. With this configuration, the connection layer can be suitably used as a connection layer.

[0098] In the light emitting device (100, 101, 102) of aspect 9 of the present invention, in any of aspects 1 to 8, the main component of the main body (10) may be copper. According to the above structure, by making the main component of the main body copper, heat dissipation from the semiconductor laser element can be appropriately performed.

[0099] In the light emitting device (100, 101, 102) of aspect 10 of the present invention, in any one of aspects 1 to 9, at least the surface of the bonding region (50) of the main body (10) may be coated with gold. With the above configuration, connection to the solder layer can be appropriately performed.

[0100] The manufacturing method of the light-emitting device (100, 101, 102) involved in mode 11 of the present invention is characterized in that the light-emitting device has a main body (10) which is made of metal and forms an internal space (11) and an opening (13) passing through the internal space and the outside, at least one semiconductor laser element (1) is mounted in the internal space, and the manufacturing method is a method for manufacturing a light-emitting device in which a sealing glass (lens array 20) is bonded to the main body in a manner covering the opening to airtightly seal the internal space of the main body, and a bonding agent between the sealing glass and the main body is formed on a surface (23) on the main body side of the sealing glass. A base layer (30) having a pre-patterned bonding area and a solder layer (40) on the base layer, the base layer being made of a metal having a thermal expansion coefficient between the thermal expansion coefficient of the sealing glass and the thermal expansion coefficient of the metal constituting the main body, and including a close-fitting layer (31) formed on the surface of the sealing glass, a barrier layer (32) on the close-fitting layer, and a connecting metal layer (33) on the barrier layer, at least the surface of the bonding area of ​​the main body being pre-covered with a gold layer, and the bonding of the sealing glass to the main body being performed by heating the bonding area to alloy the connecting metal layer and the solder layer, and the solder layer and the gold layer. According to the above structure, the same effect as the first aspect can be achieved.

[0101] The present invention is not limited to the above-described embodiments. Various modifications can be made within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Furthermore, new technical features can be formed by combining the technical means disclosed in the various embodiments.

Claims

1. A light emitting device, characterized in that: include: a main body portion made of metal and having an internal space and an opening extending through the internal space and the outside, wherein at least one semiconductor laser element is mounted in the internal space; and Sealing glass is bonded to the main body in a manner covering the opening to airtightly seal the internal space of the main body. A base connection layer is provided on the main body side surface of the sealing glass in a bonding region between the sealing glass and the main body, the base connection layer being made of a metal having a thermal expansion coefficient between the thermal expansion coefficient of the sealing glass and the thermal expansion coefficient of the metal constituting the main body. The sealing glass is bonded to the main body via the base connection layer and the connection layer containing solder. The main body is provided with a countersink portion around the opening portion, the countersink portion being recessed from the outer surface of the main body and having a bottom surface parallel to the outer surface. The sealing glass is bonded to the main body at the bottom surface of the countersunk portion. A groove portion that is deeper than the bottom surface of the countersunk portion is provided along the periphery of the countersunk portion. The groove portion is located between the countersunk portion and the main body portion. The solder is accumulated in the groove portion and does not creep between the sealing glass and the main body portion.

2. The light emitting device according to claim 1, wherein The sealing glass has a lens portion at a position through which light emitted from the semiconductor laser element passes.

3. The light emitting device according to claim 1 or 2, characterized in that: The base connection layer includes an adhesion layer formed on a surface of the sealing glass and a barrier layer formed on the adhesion layer.

4. The light emitting device according to claim 3, characterized in that The close-fitting layer is composed of a metal with chromium or titanium as the main component. The barrier layer is composed of a metal having platinum as a main component.

5. The light emitting device according to claim 1 or 2, characterized in that: A plurality of the semiconductor laser elements are mounted in the internal space of the main body.

6. The light emitting device according to claim 1 or 2, characterized in that: The connection layer is made of a metal mainly composed of gold, gold and tin, or tin, silver and copper.

7. The light emitting device according to claim 1 or 2, characterized in that: The main component of the main body is copper.

8. The light emitting device according to claim 1 or 2, characterized in that: At least the surface of the bonding region of the main body is coated with gold.

9. A method for manufacturing a light emitting device, characterized in that: The light emitting device comprises a main body, which is made of metal and has an internal space and an opening that passes through the internal space and the outside. At least one semiconductor laser element is mounted in the internal space. The manufacturing method is to: A method for manufacturing a light emitting device comprising bonding a sealing glass to the main body so as to cover the opening and hermetically sealing the internal space of the main body. A base layer in which the bonding area between the sealing glass and the main body is patterned in advance and a solder layer on the base layer are formed on the surface of the main body side of the sealing glass. The base layer is made of a metal having a thermal expansion coefficient between that of the sealing glass and that of the metal constituting the main body, and includes a contact layer formed on a surface of the sealing glass, a barrier layer on the contact layer, and a connection metal layer on the barrier layer. The surface of at least the bonding area of ​​the main body is covered with a gold layer in advance. The sealing glass is bonded to the main body by heating the bonding area to alloy the connection metal layer and the solder layer, and the solder layer and the gold layer. The main body is provided with a countersink portion around the opening portion, the countersink portion being recessed from the outer surface of the main body and having a bottom surface parallel to the outer surface. The sealing glass is bonded to the main body at the bottom surface of the countersunk portion. A groove portion that is deeper than the bottom surface of the countersunk portion is provided along the periphery of the countersunk portion. The groove portion is located between the countersunk portion and the main body portion. Solder is accumulated in the groove portion, and creep does not occur between the sealing glass and the main body portion.

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