Laser diode
By combining a copper wafer substrate and Kovar material with a reflector and dual collimating lenses, the problem of achieving high power output for a TO9 socket-packaged laser diode without increasing its size was solved. This achieved efficient heat dissipation and beam adjustment for the laser diode, expanding its application range and reducing costs.
Patent Information
- Application Number
- CN202511654869.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-12
- Publication Date
- 2026-02-06
AI Technical Summary
Existing high-power laser diodes in TO9 socket packages cannot achieve higher laser output without changing the size, resulting in increased product size, higher costs, and increased system complexity, which limits their application in space-sensitive or cost-sensitive scenarios.
By employing a combination design of copper wafer substrate and Kovar material, along with pins, caps, mirrors, and dual collimating lenses, the thermal conductivity of the copper wafer substrate and the hermeticity of Kovar material are used to achieve efficient heat dissipation and optical path adjustment of the laser chip, forming a sealed cavity. The dual collimating lenses are used to adjust the laser beam into a near-parallel beam, simplifying the optical design.
This technology enables an increase in laser power without increasing size, expands the depth and breadth of applications, simplifies optical design, reduces material and production costs, and improves device reliability and heat dissipation performance.
Smart Images
Figure CN121484643A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor technology, and more particularly to a laser diode. Background Technology
[0002] In the application of high-power laser diodes, TO9 socket laser diodes are widely used in automotive lighting, mobile lighting, laser engraving, industrial processing, and medical equipment due to their compact structure and good heat dissipation. However, as the demand for laser power in application scenarios continues to increase, the performance limitations of existing TO9 socket high-power laser diodes are gradually becoming apparent.
[0003] Currently, laser diodes using TO9 socket packages typically achieve laser output with an optical power of up to 5W (corresponding to an electrical power of 12W), which basically meets the needs of low-to-medium power applications. However, when applications require higher power laser output (such as 10W optical power), existing technologies usually employ a method of merging two 5W optical power laser diodes through optical path merging. While this approach can meet power requirements, it also introduces significant drawbacks: First, using two laser diodes leads to a substantial increase in product size, hindering miniaturization design; second, the dual-laser-diode configuration significantly increases material and production costs; and finally, the need for an additional optical path merging structure increases system complexity and assembly difficulty.
[0004] The aforementioned technological bottlenecks limit the application of high-power laser diodes in space-sensitive or cost-sensitive scenarios. For example, in fields such as new energy vehicle lighting, mobile lighting, portable medical devices, and miniature laser processing tools, users want to maintain the existing product's structural dimensions while demanding higher laser power output. However, existing technologies cannot meet these requirements by simply increasing power without altering the product's size and structure. Therefore, developing a laser diode that achieves higher optical power output without changing its size, while also possessing good thermal conductivity, has become a pressing technical problem to be solved in this field. Summary of the Invention
[0005] The purpose of this invention is to provide a laser diode.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: A laser diode includes a socket, pins, a cap, a reflector, and a dual collimating lens. The socket includes a copper circular substrate, a Kovar sleeve, a sealing glass, and a Kovar ring. The copper circular substrate has a cylindrical support and an annular groove surrounding the support. The support has two pin holes that communicate vertically. The pins are encapsulated in the pin holes by the sealing glass and the Kovar sleeve. The Kovar ring is brazed into the annular groove. The cap is resistance welded to the Kovar ring to form a sealed cavity. The support is placed in the sealed cavity. At least one laser COS is mounted on the support. The laser COS is connected to the pins by a bonding wire and a jumper. The reflector is mounted on the support. The dual collimating lens is mounted on the top of the cap. When the laser COS is working, the emitted laser is horizontal. The reflector adjusts the horizontal laser to a vertical laser. The laser is emitted from the window of the cap and collimated into a collimated laser beam by the dual collimating lens.
[0007] Furthermore, the copper wafer substrate is oxygen-free copper, the pins are valve-capable pins, and the bottom of the copper wafer substrate contacts an external heat sink for heat dissipation.
[0008] Furthermore, the sealed cavity inside the cap is filled with a predetermined gas or a vacuum.
[0009] Furthermore, the jumper stand is adhered to the support platform by an adhesive material. The jumper stand is an insulating ceramic with a copper-plated upper surface and a gold-plated outer surface.
[0010] Furthermore, the laser COS is adhered to the support platform with silver paste, and the reflector is adhered to the support platform with adhesive. The optical path of the laser COS faces the reflector and is horizontal. The reflector is a plane mirror with a laser wavelength total reflection film coated on its surface and has a tilt angle of 45 degrees. The horizontal optical path of the laser COS is adjusted to a vertical optical path by the reflector.
[0011] Furthermore, the surface of the tube seat is plated with nickel-gold or nickel-palladium-gold.
[0012] Furthermore, the valveable sleeve is brazed into the pin hole, and the pin is sealed within the valveable sleeve by sealing glass.
[0013] Furthermore, the top of the tube cap is provided with a window, and the window is enclosed with a window glass. The dual collimating lens is installed on the tube cap at the window glass. The laser of the laser COS passes through the window glass and the dual collimating lens in sequence, and the two laser beams are shaped into a collimated laser beam by the dual collimating lens.
[0014] Furthermore, the cap is a valveable cap with a nickel-plated surface.
[0015] Furthermore, the bonding wire is a wire connecting the chip electrode and pin of the laser COS, and is a bonding gold wire, a bonding silver wire, or a bonding alloy wire.
[0016] By adopting the above technical solution, the present invention has the following advantages compared with the prior art: 1. This invention uses a copper circular substrate to replace the Kovar material circular substrate with low thermal conductivity, eliminating the thermal bottleneck in the heat conduction channel and meeting the heat conduction requirements of a single or dual laser COS under the same light source volume. At the same time, the pins are sealed by sealing glass and Kovar circular sleeve, and the Kovar circular sleeve is then sealed to the pin hole by brazing, which meets the key requirements of laser diode in terms of airtightness and electrical insulation, ensuring the reliability of the device under high temperature, high power or long-term operation.
[0017] 2. This invention uses a tube base with a cylindrical support, which can hold multiple laser COS, thereby increasing the power of the laser diode. It can form an ultra-high power collimated laser dual-source TO9 diode with an optical power of over 10 watts and an electrical power of over 24 watts, greatly expanding the depth and breadth of application of a single laser diode. At the same time, the size remains unchanged. With the same TO9 diode, the laser white light irradiation distance can be doubled. For the same laser diode size, the power of laser cutting and laser engraving is increased, which can expand the application range of products and shorten the laser processing time.
[0018] 3. This invention employs a double collimating lens, which can collide two nearly parallel laser beams emitted by the laser chip, one with a horizontal (slow axis) beam angle of 5-15 degrees and the other with a vertical (fast axis) beam angle of 30-50 degrees. These beams then converge into a single nearly parallel beam with a beam angle of ±1 degree at a distance of 1 meter, greatly simplifying the optical design in practical applications and reducing the required optical components. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the inside of the cap of the present invention; Figure 3 This is an exploded view of the cap structure of the present invention; Figure 4 This is an overall exploded view of the present invention; Figure 5 This is a cross-sectional view of the present invention; Figure 6 This is the optical path diagram of the present invention; Figure 7 This is a schematic diagram of a side-mounted die holder for a single-laser COS.
[0020] Explanation of reference numerals in the attached figures: 1. Tube socket; 2. Tube pin; 3. Tube cap; 4. Reflector; 5. Double collimating lens; 6. Laser COS; 7. Bonding wire; 8. Jumper station; 9. Solder ring; 11. Copper round substrate; 12. Kovar round sleeve; 13. Sealing glass; 14. Kovar ring; 111. Support platform; 112. Annular groove; 113. Pin hole. Detailed Implementation
[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0022] It should be noted that in this invention, the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are all based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element of this invention must have a specific orientation, and therefore should not be construed as a limitation of this invention. Example
[0023] Cooperate Figures 1 to 7 As shown, this invention discloses a laser diode, including a socket 1, pins 2, a cap 3, a reflector 4, and a dual collimating lens 5. The socket 1 includes a copper wafer substrate 11, a Kovar sleeve 12, a sealing glass 13, and a Kovar ring 14. The copper wafer substrate 11 has a cylindrical support 111 and an annular groove 112 surrounding the support 111. The support 111 has two pin holes 113 that communicate vertically. The pins 2 are encapsulated in the pin holes 113 by the sealing glass 13 and the Kovar sleeve 12. The Kovar ring 14 is encapsulated in the annular groove 112 by soldering. By creating the annular groove 112 on the copper wafer substrate 11 and soldering the Kovar ring 14 for mounting the cap 3, the requirements are met. To meet the requirements of airtightness and mechanical protection of laser diodes and laser COS, the cap 3 is welded to the Kovar ring 14 by resistance welding to form a sealed cavity. The support platform 111 is placed in the sealed cavity, and at least one laser COS6 is installed on the support platform 111. In this embodiment, two laser COS6 are preferred. The laser COS6 is connected to the pin 2 through the binding wire 7 and the jumper 8. The reflector 4 is installed on the support platform 111, and the double collimating lens 5 is installed on the top of the cap 3. When the laser COS6 is working, the laser emitted is horizontal. After being reflected by the reflector 4, the horizontal laser is adjusted to a vertical laser. The laser is emitted from the window of the cap 3 and becomes a collimated laser beam after being passed through the double collimating lens 5.
[0024] The support platform 111 and the copper wafer substrate 11 are preferably integrated. The copper wafer substrate 11 is made of oxygen-free copper, and the pin 2 is a valveable pin 2. The bottom of the copper wafer substrate 11 contacts the external heat sink for heat dissipation. The cap 3 is a valveable cap 3, and its surface is plated with nickel. The Kovar ring 14 is welded to the cap 3 by resistance welding to install and fix the cap 3.
[0025] The Kovar alloy in this embodiment is an iron (Fe)-nickel (Ni)-cobalt (Co) ternary alloy. Because its coefficient of thermal expansion (CTE) matches that of hard glass, ceramics and semiconductor materials, it is widely used in electronic packaging, lasers, aerospace and other fields.
[0026] The bottom of the copper circular substrate 11 contacts an external heat sink for heat dissipation. The external heat sink can be a metal heat sink, a ceramic substrate, or a heat pipe, or it can be a semiconductor cooling chip, configured according to requirements. This embodiment does not limit the configuration.
[0027] In this embodiment, the laser COS6 stands for Chip On Submount, which is a combination of a laser chip and a heat sink. When the laser COS6 is working, it generates heat, which is conducted along the support 111 to the copper wafer substrate 11, and finally directed to the external heat sink, which then completes the heat dissipation.
[0028] The sealed cavity inside the cap 3 is filled with a set gas or a vacuum. In this embodiment, the set gas is preferably an inert gas, or it may be a mixture of inert gases; this embodiment is not limited to this.
[0029] The jumper stand 8 is adhered to the support 111 by an adhesive material. The jumper stand 8 is an insulating ceramic with a copper-plated upper surface and a gold-plated outer surface. In this embodiment, the adhesive material used for the jumper stand 8 is preferably UV-cured adhesive, thermosetting adhesive, or silver paste.
[0030] The laser COS6 is adhered to the support 111 using silver paste. The reflector 4 is also adhered to the support 111 using adhesive. The optical path of the laser COS6 faces the reflector 4 and is horizontal. The reflector 4 is a plane mirror with a total internal reflection film coated with the laser wavelength, tilted at 45 degrees. The reflector 4 adjusts the horizontal optical path of the laser COS6 to a vertical one. The silver paste, such as sintered silver, is a high thermal conductivity material used to bond the laser COS6; it can also be replaced by high thermal conductivity sintered gold or eutectic solder. The adhesive includes UV adhesives, thermosetting adhesives, and also silver paste, sintered silver, and sintered gold.
[0031] This embodiment employs a special double-collimating lens, which can collide two nearly parallel laser beams—one with a horizontal (slow axis) beam angle of 5-15 degrees and the other with a vertical (fast axis) beam angle of 30-50 degrees—emitted from the laser chip. These beams then converge into a single, nearly parallel beam with a ±1 degree beam angle at a distance of 1 meter. This significantly simplifies the optical design in practical applications and reduces the number of required optical components.
[0032] The surface of tube base 1 is plated with nickel-gold or nickel-palladium-gold. That is, the entire metal surface of tube base 1 is plated with nickel-gold or nickel-palladium-gold, which improves weldability, enhances oxidation and corrosion resistance, optimizes heat conduction, and reduces interfacial thermal resistance, helping the heat-conducting tube base 1 to quickly dissipate the heat generated by the laser diode. The valveable sleeve is brazed into the pin hole 113, and the pin 2 is encapsulated within the valveable sleeve by a sealing glass 13. In this embodiment, the pin hole 113 passes through the support 111 and the copper wafer substrate 11, allowing them to communicate vertically. The valveable sleeve is brazed into the pin hole 113, and the pin 2 is inserted into the valveable sleeve and sealed and fixed by the sealing glass 13. The sealing glass 13 serves as a gap between the pin 2 and the valveable sleeve 3.
[0033] The top of the cap 3 has a window, and the window is enclosed with a window glass. The double collimating lens 5 is installed on the cap 3 at the window glass. The laser of the laser COS6 passes through the window glass and the double collimating lens 5 in sequence, and the two laser beams are shaped into a collimated laser beam by the double collimating lens 5.
[0034] In this embodiment, the window glass is preferably sapphire glass, fused silica, or optical glass, and is sealed to the window by an adhesive such as low-temperature glass welding to ensure the cap 3 is sealed.
[0035] In this embodiment, the dual collimating lens 5 can be a window that is independently fixed to the cap 3, or it can be fixed to the cap 3 with glue.
[0036] The bonding wire 7 is a wire connecting the positive and negative electrodes of the laser COS6 chip and pin 2, and is a bonding gold wire, bonding silver wire, or bonding alloy wire. The laser COS6 is bonded and fixed to the support 111 of the tube socket 1 by silver paste bonding process or sintering process; the bonding gold wire connects the positive and negative electrodes of two or more chips in series with the corresponding positive and negative electrodes of pin 2 of the diode through a bonding machine.
[0037] In this embodiment, a copper circular substrate 11 is used instead of a Kovar circular substrate with low thermal conductivity, which removes the thermal bottleneck in the heat conduction channel and meets the heat conduction requirements of a single or dual laser COS6 with the same light source volume. At the same time, the pin 2 is sealed by the sealing glass 13 and the Kovar circular sleeve 12, and the Kovar circular sleeve 12 is sealed to the pin hole 113 by brazing to form a brazing ring 9, which meets the key requirements of the laser diode in terms of airtightness and electrical insulation, and ensures the reliability of the device under high temperature, high power or long-term operation.
[0038] In this embodiment, the Kovar ring, Kovar sleeve, and Kovar circular substrate can all be replaced by alloy steel such as SPCC.
[0039] This embodiment uses a tube holder 1 with a cylindrical support 111, which can accommodate multiple laser COS6 diodes, thereby increasing the power of the laser diode. Preferably, two laser COS6 diodes are used, which contrasts with existing side-bonded tube holders that can only accommodate one laser COS6 diode. Figure 7 As shown, not only does it have good thermal conductivity, but it can also increase power, enabling the formation of ultra-high power collimated laser dual-source TO9 diodes with optical power of over 10 watts and electrical power of over 24 watts. This greatly expands the depth and breadth of applications for a single laser diode, while maintaining the same size. Under the same TO9 diode, the laser white light irradiation distance can be doubled. For the same laser diode size, the power of laser cutting and laser engraving can be increased, which can expand the application range of products and shorten the laser processing time.
[0040] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A laser diode, characterized in that: The device includes a socket, pins, a cap, a reflector, and a dual collimating lens. The socket comprises a copper circular substrate, a Kovar sleeve, a sealing glass, and a Kovar ring. The copper circular substrate has a cylindrical support and an annular groove surrounding the support. The support has two pin holes that communicate vertically. The pins are encapsulated in the pin holes by the sealing glass and the Kovar sleeve. The Kovar ring is brazed into the annular groove. The cap is resistance welded to the Kovar ring to form a sealed cavity. The support is placed in the sealed cavity. At least one laser COS is mounted on the support. The laser COS is connected to the pins via a binding wire and a jumper. The reflector is mounted on the support. The dual collimating lens is mounted on the top of the cap. When the laser COS is working, the emitted laser is horizontal. After being reflected by the reflector, the horizontal laser is adjusted to a vertical laser. The laser is emitted from the window of the cap and becomes a collimated laser beam through the dual collimating lens.
2. A laser diode as described in claim 1, characterized in that: The copper wafer substrate is made of oxygen-free copper, the pins are valve-compatible pins, and the bottom of the copper wafer substrate contacts an external heat sink for heat dissipation.
3. A laser diode as described in claim 1, characterized in that: The sealed cavity inside the cap is filled with a specified gas or a vacuum.
4. A laser diode as described in claim 1, characterized in that: The jumper stand is attached to the support platform by adhesive material. The jumper stand is an insulating ceramic with copper-plated upper surface and gold-plated outer surface.
5. A laser diode as described in claim 1, characterized in that: The laser COS is adhered to the support platform with silver paste, and the reflector is adhered to the support platform with adhesive. The optical path of the laser COS faces the reflector and is horizontal. The reflector is a plane mirror with a laser wavelength total reflection film coated on its surface and has a tilt angle of 45 degrees. The horizontal optical path of the laser COS is adjusted to a vertical optical path by the reflector.
6. A laser diode as described in claim 1, characterized in that: The surface of the tube seat is plated with nickel-gold or nickel-palladium-gold.
7. A laser diode as described in claim 1, characterized in that: The valveable sleeve is brazed into the pin hole, and the pin is sealed inside the valveable sleeve with sealing glass.
8. A laser diode as described in claim 1, characterized in that: The top of the tube cap is provided with a window, and the window is enclosed with a window glass. The dual collimating lens is installed on the tube cap at the window glass. The laser of the laser COS passes through the window glass and the dual collimating lens in sequence, and the two laser beams are shaped into a collimated laser beam by the dual collimating lens.
9. A laser diode as described in claim 8, characterized in that: The cap is a valveable cap with a nickel-plated surface.
10. A laser diode as described in claim 1, characterized in that: The bonding wire is a wire connecting the chip electrode and pin of the laser COS, and can be a bonding gold wire, a bonding silver wire, or a bonding alloy wire.