US-12627116-B2 - Light source device and method of manufacturing same

US12627116B2US 12627116 B2US12627116 B2US 12627116B2US-12627116-B2

Abstract

A light source device includes: a substrate having a support face; a lateral wall part disposed on the substrate and having an upper face and inner wall faces, the inner wall faces defining a space; a laser diode located in the space; a first submount having a mounting face bonded to an upper face of the laser diode, and an upper face located opposite the mounting face; a sealing member bonded to the upper face of the lateral wall part and the upper face of the first submount, thereby sealing the space; a heat dissipating block located above the first submount; and a heat conducting member located between the first submount and the heat dissipating block.

Inventors

Tadaaki Miyata

Assignees

NICHIA CORPORATION

Dates

Publication Date: 20260512
Application Date: 20230324
Priority Date: 20220328

Claims (17)

1 . A light source device comprising: a substrate having a support face; a lateral wall part disposed on the substrate and having an upper face and inner wall faces, the inner wall faces defining a space; a laser diode located in the space; a first submount having a mounting face bonded to an upper face of the laser diode, and an upper face located opposite the mounting face; a sealing member bonded to the upper face of the lateral wall part and the upper face of the first submount, thereby sealing the space; a heat dissipating block located above the first submount; and a heat conducting member located between the upper face of the first submount and a lowermost face of the heat dissipating block; wherein: a height of the upper face of the lateral wall part from the support face differs from a height of the upper face of the first submount from the support face; the heat conducting member is in thermal contact with the first submount and the heat dissipating block; and the heat dissipating block is bonded to the upper face of the lateral wall part via the sealing member.
2 . The light source device according to claim 1 wherein the heat conducting member has a thermal conductivity of 10 W/mK or higher.
3 . The light source device according to claim 1 , wherein the heat dissipating block is bonded to the sealing member via a bonding member made of an inorganic material, and the upper face of the lateral wall part is bonded to the sealing member via the bonding member.
4 . The light source device according to claim 3 , wherein the bonding member positioned between the heat dissipating block and the sealing member has an opening that connects a space between the first submount and the heat dissipating block in which the heat conducting member is located to an area outside the light source device.
5 . The light source device according to claim 4 , wherein: the laser diode has an emission face that has an emission region through which laser light is emitted and that opposes one of the inner wall faces of the lateral wall part, and a rear face located opposite the emission face, and the opening is located between the heat dissipating block and the sealing member on a rear face side of the laser diode.
6 . The light source device according to claim 3 wherein a hardness of the bonding member is higher than a hardness of the heat conducting member.
7 . The light source device according to claim 1 , wherein: the upper face of the lateral wall part has a rectangular frame shape when viewed from above in a direction normal to the support face, and the heat dissipating block is supported along at least two of the four sides of a periphery of the upper face of the lateral wall part.
8 . The light source device according to claim 1 wherein the sealing member is made of metal foil.
9 . The light source device according to claim 8 , wherein the sealing member includes a first portion bonded to the upper face of the first submount, a second portion bonded to the upper face of the lateral wall part, a connecting portion connecting the first portion and the second portion, a first deformed part located at a border between the first portion and the connecting portion, and a second deformed part located at a border between the second portion and the connecting portion.
10 . The light source device according to claim 9 , wherein at least part of the first portion is located between the heat conducting member and the first submount.
11 . The light source device according to claim 9 , wherein the first deformed part is located inward of the periphery of the first submount when viewed from above in a direction normal to the support face.
12 . The light source device according to claim 1 , wherein the height of the upper face of the first submount from the support face is smaller than the height of the upper face of the lateral wall part from the support face.
13 . The light source device according to claim 1 , wherein: the height of the upper face of the first submount from the support face is greater than the height of the upper face of the lateral wall part from the support face, and the heat dissipating block has a recess that houses the heat conducting member and at least a portion of the first submount.
14 . The light source device according to claim 1 , wherein at least a portion of the periphery of the heat conducting member is located outward of the periphery of the first submount when viewed from above in a direction normal to the support face.
15 . The light source device according to claim 1 , further comprising a second submount having a lower face bonded to the support face, and a mounting face located opposite the lower face where the laser diode is/are disposed, the laser diode being bonded to the support face via the second submount.
16 . A method of manufacturing a light source device comprising steps of: providing a light source unit comprising a submount, and a laser diode bonded to the submount; bonding the light source unit to a support face of a substrate such that the submount is above the laser diode; bonding a lateral wall part to the support face of the substrate such that the lateral wall part surrounds the light source unit; bonding a sealing member to the submount and the lateral wall part to seal the light source unit in a space defined by the substrate and the lateral wall part; disposing a heat conducting member above the submount of the light source unit, the heat conducting member having a first overall height and a first overall width; and deforming the heat conducting member to have a second overall height less than the first overall height and a second overall width greater than the first overall width, and bonding a heat dissipating block to the lateral wall part via the sealing member thereby bringing the heat dissipating block into thermal contact with the heat conducting member.
17 . The method of manufacturing a light source device according to claim 16 , further comprising a step of hardening the heat conducting member, wherein a hardness of the heat conducting member subsequent to hardening is higher than a hardness prior to hardening.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2022-052066, filed on Mar. 28, 2022, the entire contents of which are incorporated herein by reference. BACKGROUND The present disclosure relates to a light source device and a method of manufacturing the light source device. A light emitting device equipped with a sealing structure to seal the space in a package in which a laser diode is housed has been developed. Japanese Patent Publication No. 2016-167492 discloses a light emitting device comprising an upper substrate, a lower substrate opposing the upper substrate, a submount supporting a laser diode, and a wavelength conversion part. In this light emitting device, the laser diode is disposed between the lower substrate that is bonded to the submount and the upper substrate. The wavelength conversion part forms a space in which the laser diode is sealed. SUMMARY An embodiment of the present disclosure provides a new sealing structure for hermetically sealing the space in the package in which a laser diode is housed. A light source device according to the present disclosure, in a non-limiting exemplary embodiment, includes a substrate having a support face, a lateral wall part disposed on the substrate and having a first upper face and inner wall faces, the inner wall faces defining a space, one or more laser diodes located in the space, a first submount having a first mounting face bonded to the upper face(s) of the laser diode(s) and a second upper face located opposite the first mounting face, a sealing member bonded to the first upper face and the second upper face thereby sealing the space, a heat dissipating block located above the first submount, and a heat conducting member located between the first submount and the heat dissipating block, in which the height of the first upper face from the support face differs from the height of the second upper face from the support face, the heat conducting member is in thermal contact with the first submount and the heat dissipating block, and the heat dissipating block is bonded to the first upper face of the lateral wall part via the sealing member. A method of manufacturing a light source device according to the present disclosure, in a non-limiting exemplary embodiment, includes a step of bonding a light source unit having a submount and a laser diode bonded to the submount to the support face of a substrate, a step of bonding a lateral wall part to the support face to surround the light source unit, a step of bonding a sealing member to the submount and the lateral wall part to seal the light source unit in the space defined by the substrate and the lateral wall part, a step of disposing a heat conducting member above the submount of the light source unit, and a step of deforming the heat conducting member to bond a heat dissipating block to the lateral wall part via the sealing member thereby bringing the heat dissipating block into thermal contact with the heat conducting member. According to an exemplary embodiment of the present disclosure, a new sealing structure can be provided for hermetically sealing the space in the package in which a laser diode is housed. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view paralleling a YZ plane of a light source device according to a first embodiment of the present disclosure. FIG. 2 is a cross-sectional view paralleling an XY plane of the light source device according to the first embodiment of the present disclosure. FIG. 3 is a plan view of the light source device according to the first embodiment of the present disclosure. FIG. 4 is a cross-sectional view paralleling an XY plane of a light source device according to the first embodiment of the present disclosure in which the external connection electrodes are disposed on the support face of the substrate. FIG. 5A is an enlarged cross-sectional view enlarging the portion where the sealing member is bonded to the first upper face of the lateral wall part and the lower face of the heat dissipating block in FIG. 1. FIG. 5B is an enlarged cross-sectional view enlarging the portion where the sealing member is bonded to the first upper face of the lateral wall part and the lower face of the heat dissipating block in FIG. 2. FIG. 6 is a cross-sectional view paralleling a YZ plane of a light source device of another form according to the first embodiment of the present disclosure. FIG. 7 is a top plan view of the sealing member having another structure. FIG. 8 is a cross-sectional view paralleling an XY plane of a light source device of another form according to the first embodiment. FIG. 9 is a cross-sectional view paralleling a YZ plane of the light source device of another form according to the first embodiment. FIG. 10 is a cross-sectional view paralleling a YZ plane of a light source device of another form according to the first embodiment. FIG. 11 is a