Laser packaging module

Abstract

A laser packaging module (10), comprising a base (12), wherein the base (12) comprises a boss (121), an optical window bonding pad (122), internal bonding pads (123), and external bonding pads (124), and the internal bonding pads (123) and the external bonding pads (124) are electrically connected by means of an inner circuit layer of the base (12); an optical window (16), wherein the optical window (16) is brazed on the optical window bonding pad (122) of the base (12), and the optical window (16) and the base (12) define an accommodating space (15); and laser assemblies (18), wherein the laser assemblies (18) are arranged on the boss (121) of the base (12), the laser assemblies (18) are accommodated in the accommodating space (15), the laser assemblies (18) are electrically connected to the internal bonding pads (123), and laser light emitted by the laser assemblies (18) exits by means of the optical window (16). The optical window (16) and the base (12) of the laser packaging module (10) are brazed together, so that process difficulty of the laser packaging module (10) is reduced while the brazing quality is ensured.

Description

Laser packaging module Technical Field

[0001] The utility model relates to the technical field of optics, and in particular to a laser packaging module. Background Art

[0002] With the continuous improvement of laser chip electro-optical conversion efficiency and output optical power, as well as continuous breakthroughs in laser light source technology, laser chips are finding increasingly widespread application in laser lighting and display fields. To meet market demand, laser chip packaging technology is also undergoing continuous advancement and improvement. Sealing is a crucial factor in determining product cost and quality. Existing laser chips are sealed using glue dispensers, but this method has poor reliability and product quality needs improvement, further limiting the development of laser chip packaging technology.

[0003] Utility Model Content

[0004] The purpose of this utility model is to provide a new laser packaging module to solve the above problems.

[0005] The embodiments of the present invention achieve the above-mentioned objectives through the following technical solutions.

[0006] The utility model provides a laser packaging module, characterized in that it includes: a base, the base includes a boss, a light window pad, an internal pad and an external pad, and the internal pad and the external pad are connected through the internal circuit layer of the base; a light window, the light window is welded on the light window pad of the base, and the light window and the base form a receiving space; a laser assembly, the laser assembly is arranged on the boss of the base, the laser assembly is received in the receiving space, the laser assembly is electrically connected to the internal pad, and the laser emitted by the laser assembly is emitted through the light window.

[0007] In one embodiment, the laser packaging module further includes a collimating lens, which is installed on a side of the light window away from the base, and is used to shape the light emitted by the laser assembly into parallel light.

[0008] In one embodiment, the collimating lens includes two collimating lens units, each of which corresponds to one of the laser assemblies to collimate the laser light emitted by the laser assembly.

[0009] In one embodiment, the light window is a hollow cylindrical structure, and the cross section of the light window in a direction perpendicular to the base is a circular ring, and the width of the circular ring is smaller than the width of the light window welding plate.

[0010] In one embodiment, the light window includes side walls and a top wall, wherein the side walls are connected to the top wall in a ring shape, and a light-transmitting portion is provided in the middle area of ​​the top wall, and the light-transmitting portion is used to transmit the output light of the laser assembly.

[0011] In one embodiment, the laser assembly includes a laser chip, a heat sink carrier and a reflector, wherein the heat sink carrier is arranged on the boss of the base, the laser chip is arranged on the heat sink carrier, and the reflector is arranged on the optical path of the output light of the laser chip.

[0012] In one embodiment, the reflective component includes a reflective surface opposite to the light outlet of the laser chip, and the reflective surface forms an angle of 45° with the plane where the base is located.

[0013] In one embodiment, the laser assembly may include a plurality of groups of the laser chips and the reflective elements, and the plurality of groups of the laser chips and the reflective elements are arrayed on the base.

[0014] In one embodiment, the base is a double-layer MPCB board, and the material of the double-layer MPCB board is copper.

[0015] In one embodiment, the internal solder pad is arranged in the receiving space, and the external solder pad is arranged outside the receiving space. The double-layer MPCB board includes an internal circuit layer, and the internal circuit layer is buried in the base. The internal solder pad and the external solder pad are connected through the internal circuit layer.

[0016] Compared with the prior art, the optical window and base of the laser packaging module provided by the present invention are brazed, which reduces the process difficulty of the laser packaging module while ensuring the welding quality. In addition, a collimating lens is installed on the optical window so that the laser can be collimated. By providing a double-layer MPCB board, the present application allows the solder pads sealed in the receiving space to be led out through the internal circuit layer of the double-layer MPCB board, thereby improving the process yield of the laser packaging module and improving the sealing reliability of the laser packaging module.

[0017] These and other aspects of the present invention will be more clearly understood in the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0019] FIG1 is a schematic diagram of the overall structure of the laser packaging module provided by the present invention.

[0020] FIG2 is a schematic diagram of the optical window structure of the laser packaging module provided by the present invention.

[0021] FIG3 is a schematic structural diagram of the base of the laser packaging module provided by the present invention.

[0022] FIG4 is a schematic structural diagram of the base of the laser packaging module provided by the present invention.

[0023] FIG5 is a schematic structural diagram of the base and light window of the laser packaging module provided by the present invention.

[0024] FIG6 is a schematic structural diagram of the base, light window and collimating lens of the laser packaging module provided by the present invention.

[0025] FIG7 is a schematic diagram of the laser component structure of the laser packaging module provided by the present invention.

[0026] FIG8 is a schematic structural diagram of the base circuit layer of the laser packaging module provided by the present invention. DETAILED DESCRIPTION

[0027] To facilitate understanding of the embodiments of the present invention, a more comprehensive description of the embodiments of the present invention will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the art of the present invention. The terms used herein in the embodiments of the present invention are only for the purpose of describing specific implementation methods and are not intended to limit the present invention.

[0029] The utility model provides a laser packaging module, characterized in that it includes: a base, the base includes a boss, a light window pad, an internal pad and an external pad, and the internal pad and the external pad are connected through the internal circuit layer of the base; a light window, the light window is welded on the light window pad of the base, and the light window and the base form a receiving space; a laser assembly, the laser assembly is arranged on the boss of the base, the laser assembly is received in the receiving space, the laser assembly is electrically connected to the internal pad, and the laser emitted by the laser assembly is emitted through the light window.

[0030] The technical solution of the present utility model is described below through specific embodiments.

[0031] Please refer to Figures 1, 2, and 3. The present invention provides a laser packaging module 10, comprising a base 12, a light window 16, a collimating lens 17, and a laser assembly 18. The light window 16 is disposed on the base 12 and encloses a receiving space 15. The light window 16 is provided with a light-transmitting portion 161 on a side away from the base 12. The light window 16 has a top wall 164 away from the base 12 and a side wall 162 connected to the top wall. A brazing layer is provided on the surface of the side wall area of ​​the light window 16 facing the base 14 to connect the light window 16 to the base 12 to form a sealed receiving space 15. The collimating lens 17 is mounted on the side of the light window 16 away from the base 12. The collimating lens 17 is used to shape the light emitted by the laser assembly into parallel light. The collimating lens 17 and the light window 16 are bonded to the light window 16 by glue. The laser assembly 18 is located in the receiving space 15, and the laser light emitted by the laser assembly 18 is ultimately emitted from the light-transmitting portion 161 of the light window 16.

[0032] Referring to Figure 3 , specifically, the base 12 is a generally plate-like structure. It can be a regular shape, such as a rectangle, circle, oval, or hexagon, or other irregular shapes. The base 12 is used to mount the laser assembly 18 and the light window 16. In this embodiment, the base 12 is a double-layer printed circuit board (MPCB). The base 12 can be made of a copper substrate. Metal substrates have better thermal conductivity and are more conducive to heat dissipation from the laser assembly 18. In other embodiments, the base 12 can be made of ceramic or other materials, as long as they meet the requirements for mounting the light window 16. Furthermore, the base 12 includes a boss 121, which is used to set the laser assembly 18; the base 12 also includes a light window pad 122, which is used to connect to the side wall of the light window 16; the base 12 is also provided with an internal pad 123, which is connected to the laser assembly 18 through a gold wire to realize electrical input to the laser assembly 18; the base 12 is also provided with an external pad 124, which is used to connect to the power supply, and the power supply realizes electrical drive of the laser assembly 18 through the external pad. It should be noted that the external pad and the internal pad are only a relative relationship, not the actual outside and inside. In this embodiment, the outside refers to the outside of the accommodation space, and the inside refers to the inside of the accommodation space; further, since the base 12 adopts a double-layer MPCB, the internal pad and the external pad are connected through the double-layer MPCB to realize electrical drive of the laser assembly 18 in the accommodation space 15.

[0033] Please refer to Figures 2 and 4 together. In this embodiment, the light window 16 is a hollow cylindrical structure, that is, the cross-section of the light window 16 in the direction perpendicular to the base 12 is roughly a circular ring, and the width of the circular ring is smaller than the width of the light window welding disk. In order to ensure reliability when welding with the base 12, it can be integrally formed or welded from several metal plates. It should be noted that the light window 16 in this embodiment is roughly a hollow cylindrical structure, which means that the cross-section of the light window is a circular ring, and the edges and corners of the circular ring are not regular edges and corners. The receiving space 15 formed by the light window 16 and the base 12 can be used to accommodate the laser assembly 18. The material of the light window 16 can be the same as that of the base 12, such as a metal material, or it can be different from the material of the base 12, such as a ceramic material.

[0034] In other embodiments, the light window 16 may be a substantially hollow polygonal prism, that is, the cross section of the light window 16 may be a substantially polygonal ring. It is understood that the light window 16 may also be a hollow hexagonal prism or other shape, as long as it can accommodate the laser assembly 18.

[0035] As further shown in FIG. 2 , the light window 16 includes side walls 162 and a top wall 164. The side walls 162 are connected to the circular top wall 164 in an annular shape. A light-transmitting portion 161 is provided in the middle region of the circular top wall 164 for transmitting light emitted from the laser assembly 18. A surface 163 of the side wall 162 opposite the base 12 is brazed to the base to form a sealed receiving space 15. It should be noted that the side walls and top wall of the light window can be integrally formed or formed by connecting two components. The connection between the side walls and the top wall of the light window is chamfered to improve the window's usability.

[0036] Light window 16 is disposed on base 12 and encloses a receiving space. In this embodiment, light window 16 is soldered to the base. In other embodiments, a layer of adhesive may be applied to base 12 or to the side of light window 16 closest to base 12, and light window 16 may be attached to base 12 by bonding.

[0037] Please continue to refer to Figures 2 and 5. The light window 16 is roughly annular, and the material of the light window 16 can be optical glass or sapphire. The light window 16 can be made of a light-transmitting material to protect the laser assembly 18 in the receiving space without affecting the emission of the light beam, to prevent dust from falling into the laser assembly 18, and to reduce the impact of water vapor and the like on the laser assembly 18. In this embodiment, the light window 16 is made of a transparent material, and a light-transmitting portion is provided in the center area of ​​the top wall of the light window 16; in this embodiment, the light window 16 can be provided with a partially transparent area, that is, a light-transmitting area is provided in the area corresponding to the light outlet of the laser chip, and a non-light-transmitting area is provided in other areas. The advantage of this design is that the light spot shaping can be achieved simultaneously.

[0038] A portion of the side wall surface 163 of the light window 16 facing the base 12 is provided with a metal layer, the outer edge of the metal layer can be flush with the outer edge of the light window 16, and the inner edge of the metal layer can be flush with the inner edge of the light window 16, so as to increase the welding area between the light window 16 and the base 12, thereby increasing the connection strength between the light window 16 and the base 12.

[0039] In this embodiment, the width of the side wall 162 of the light window 16 is smaller than the width of the light window pad of the base 12. The purpose of this design is to increase the welding area between the light window 16 and the base 12, so that the light window is completely welded to the base 12, thereby increasing the sealing after welding and improving the stability of the package.

[0040] In this embodiment, the solder may be a circular ring-shaped integral solder piece, and the material may be Sn96.5Ag3.0Cu0.5, or a solder piece with other ratios of SnAgCu close to this ratio, or a solder piece with other components (such as SnAgInBi) with a melting point lower than 260°C.

[0041] In some other embodiments, the solder may further include multiple sections of solder pieces, there may be gaps between the solder pieces, and the multiple sections of solder pieces may be assembled into a circular ring structure.

[0042] In other embodiments, the shape of the solder may be other irregular shapes. The specific shape may be selected according to actual conditions, as long as the light window 16 can seal the base 12 after the solder melts.

[0043] Please continue to refer to Figures 1 and 6. The collimating lens 17 can be composed of two collimating lens units. In this embodiment, each collimating lens unit corresponds to a laser assembly 18 to collimate the laser emitted by the laser assembly 18, thereby improving the imaging quality of the laser. The collimating lens 17 can be bonded to the light window, wherein it can be bonded by UV glue, or other heat-curing glue or other adhesive that has good bonding properties to glass materials and low stress. It is understandable that in other embodiments, the collimating lens can also be integrally formed with the light window, that is, the surface area of ​​the light window corresponding to the light outlet of the laser chip is raised to achieve collimation of the laser. The advantage of this method is that the laser packaging module lacks an assembly step of the collimating lens and the assembly is simple, but the difficulty of the preparation process of the light window is increased.

[0044] Continuing with reference to FIG7 , the laser assembly 18 is housed within the housing space and is configured to emit laser light through the optical window 16. In this embodiment, the laser assembly 18 is disposed within the area enclosed by the projection of the inner wall of the optical window onto the base 12. The laser assembly 18 includes a laser chip 182 and a reflector 181. Both the laser chip 182 and the reflector 181 are housed within the housing space. The laser chip 182 is configured to emit laser light. In this embodiment, the laser assembly 18 further includes a heat sink 183, wherein the laser chip 182 is disposed on the surface of the heat sink 183. The heat sink 183 is configured to dissipate heat from the laser chip 182. The heat sink is welded to the boss of the base by soldering. In other embodiments, multiple laser chips correspond to one heat sink, i.e., multiple laser chips are disposed on the surface of the heat sink and share a common heat sink for heat dissipation. The reflector 181 is used to reflect the laser light toward the light-transmitting area of ​​the light window 16. In this embodiment, the reflector 181 includes a reflective surface opposite to the light outlet of the laser chip, and the reflective surface forms an angle of 45° with the plane where the base is located.

[0045] In this embodiment, the laser packaging module includes two groups of laser components, each group of laser components includes a laser chip 182, a reflector 181 and a heat sink carrier 183, wherein the two reflectors 181 are located between the two laser chips 182 and are arranged opposite to each other, and the reflective surfaces of the reflectors 181 are both facing the light outlet of the laser chip. The angle between the reflective surface and the plane where the base 12 is located can be 45°, and the laser emitted by the laser chip 182 can be emitted to the reflective surface in a direction parallel to the plane where the base 12 is located. In this way, the laser light can be reflected by the reflective surface of the reflector 181 and finally emitted in a direction perpendicular to the plane where the light window 16 is located, that is, emitted from the top of the laser packaging module 10 in a direction perpendicular to the incident direction, that is, top-emitting light. Under this condition, the light output is the largest.

[0046] In other embodiments, the angle between the reflective surface and the plane of the base 12 can be other angles, such as 30° or 60°. In other embodiments, the laser light emitted by the laser chip 182 can also be emitted to the reflective surface in a direction that forms a certain angle with the plane of the base 12. As an example, the angle can be 30°.

[0047] In some other embodiments, the laser components can also be multiple groups, that is, the number of laser chips 182 and reflectors 181 can also be three groups, four groups or more groups. Multiple groups of laser chips 182 and reflectors 181 can be arranged in an array on the base 12 or irregularly on the base 12.

[0048] Please continue to refer to Figure 8, which is a schematic diagram of the middle circuit of the double-layer MPCB of the present application. In this embodiment, the base 12 also includes an internal circuit layer, which is arranged in the base 12, that is, the circuit layer is buried in the base. The internal pad and the external pad are connected through the circuit layer to power the external pad through the power supply. The external pad will transmit the electric drive to the internal pad through the internal circuit layer. The internal pad is connected to the laser chip 182 through a gold wire to realize power supply to the laser chip 182, so that the laser chip 182 can emit laser.

[0049] The following are the steps for sealing and welding the light window 16 of the present invention:

[0050] 1. Place the laser assembly 18, solder, optical window 16 and fixture that have been dehumidified and baked into a sealed container filled with nitrogen.

[0051] 2. Place the optical window 16 equipped with the laser assembly 18 and various components on a fixture in a sealed container.

[0052] 3. Place solder on the light window pad area 122 of the base 12.

[0053] 4. Place the light window 16 on the soldering piece and align the light window 16 with the light window soldering pad area 122 of the base 12.

[0054] 5. Press the light window 16 and the base 12 tightly together on the clamps. The specific number of clamps can be determined according to needs.

[0055] 6. Place the fixture that fixes the product into the vacuum baking equipment, first evacuate the vacuum, then fill it with nitrogen, and then heat it according to the pre-set program for reflow soldering; evacuating the vacuum and filling it with nitrogen can increase the number of cycles, and the specific number of cycles depends on the needs.

[0056] 7. After reflow soldering is completed, remove the fixture from the baking equipment and remove the product from the fixture. The sealing soldering operation of the light window 16 is now completed.

[0057] In summary, the optical window 16 and the base 12 of the laser packaging module 10 provided by the present invention are welded by solder, which reduces the process difficulty of the laser packaging module 10 while ensuring the welding quality. The collimating lens 17 is installed on the optical window 16 so that the laser can be collimated and emitted. By setting a double-layer MPCB board in this application, the solder pad sealed in the receiving space is led out through the internal circuit layer of the double-layer MPCB board, thereby improving the process yield of the laser packaging module and improving the sealing reliability of the laser packaging module.

[0058] The above-described embodiments merely represent several implementation methods of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A laser packaging module, It is characterized in that include: A base, the base comprising a boss, a light window pad, an internal pad and an external pad, wherein the internal pad and the external pad are connected through an internal circuit layer of the base; A light window, wherein the light window is welded on the light window welding pad of the base, and the light window and the base form a receiving space; A laser component is arranged on the boss of the base, the laser component is accommodated in the accommodation space, the laser component is electrically connected to the internal solder pad, and the laser emitted by the laser component is emitted through the light window.

2. The laser packaging module according to claim 1, It is characterized in that It also includes a collimating lens, which is installed on a side of the light window away from the base, and is used to shape the light emitted by the laser component into parallel light.

3. The laser packaging module according to claim 2, It is characterized in that The collimating lens includes two collimating lens units, each of which corresponds to one of the laser components to collimate the laser emitted by the laser component.

4. The laser packaging module according to claim 1, It is characterized in that The light window is a hollow cylindrical structure, and the cross section of the light window in a direction perpendicular to the base is a circular ring, and the width of the circular ring is smaller than the width of the light window welding plate.

5. The laser packaging module according to claim 4, It is characterized in that The light window comprises a side wall and a top wall, wherein the side wall is connected to the top wall in a ring shape, and a light-transmitting portion is arranged in the middle area of ​​the top wall, and the light-transmitting portion is used to transmit the output light of the laser assembly.

6. The laser packaging module according to claim 1, It is characterized in that The laser assembly comprises a laser chip, a heat sink carrier and a reflector. The heat sink carrier is arranged on a boss of the base, the laser chip is arranged on the heat sink carrier, and the reflector is arranged on an optical path of an outgoing light from the laser chip.

7. The laser packaging module according to claim 6, It is characterized in that The reflective element comprises a reflective surface opposite to the light outlet of the laser chip, and the reflective surface forms an angle of 45° with the plane where the base is located.

8. The laser packaging module according to claim 7, It is characterized in that The laser assembly may include a plurality of groups of laser chips and reflective elements, and the plurality of groups of laser chips and reflective element arrays are disposed on the base.

9. The laser packaging module according to claim 1, It is characterized in that The base is a double-layer MPCB board, and the material of the double-layer MPCB board is copper.

10. The laser packaging module according to claim 9, It is characterized in that The internal pad is arranged in the receiving space, the external pad is arranged outside the receiving space, the double-layer MPCB board includes an internal circuit layer, the internal circuit layer is buried in the base, and the internal pad and the external pad are connected through the internal circuit layer.

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