A TO-can package structure of an optical emission laser

Abstract

The application provides a TO-can packaging structure of a light-emitting laser, and relates to the field of light-emitting laser packaging, and comprises a support, a pipe cap, a pin, a heat-conducting pad, a light-emitting LD chip, a monitoring PD chip and a metal fixing wire, a boss is arranged at the central part of the upper end face of the support, and the upper part of the boss is provided with the heat-conducting pad; the upper end face of the heat-conducting pad is adhered with the light-emitting LD chip and the monitoring PD chip through heat-conducting adhesive; the upper end face of the support outside the boss is fixedly connected with the pipe cap; a plurality of arc-shaped positioning blocks are fixedly connected outside the heat-conducting pad; the upper end face edges of the light-emitting LD chip and the monitoring PD chip are both welded with the metal fixing wire, and the outer end of the metal fixing wire is welded on the upper end face of the arc-shaped positioning block. Through the cooperation design of the metal fixing wire and the arc-shaped positioning block, the light-emitting LD chip and the monitoring PD chip are effectively prevented from being displaced or loosened, the stability of the light-emitting LD chip and the monitoring PD chip after packaging is improved, and the service life is prolonged.

Description

Technical Field

[0001] This invention relates to the field of optical laser packaging technology, and more particularly to a TO-can packaging structure for optical lasers. Background Technology

[0002] TO-can packaging is a coaxial packaging technology for optical emitting lasers widely used in optical communication. Due to its compact structure, low cost, and mature manufacturing process, it has become the mainstream packaging solution for the transmitting optical sub-components in optical transceiver modules. A typical TO-can package structure uses a TO socket as the base. The light-emitting LD chip and the monitoring PD chip are attached to the socket using thermally conductive adhesive. The socket cap and the socket are sealed together to form a hermetically sealed protective cavity. A lens or light-transmitting window is usually integrated into the top of the socket to achieve collimation or focused output of the beam. The light-emitting LD chip and the monitoring PD chip are electrically connected to the pins on the socket via gold wires.

[0003] In existing TO-can packaging structures, the light-emitting LD chip and the monitoring PD chip are mostly bonded and fixed to the bracket with thermally conductive adhesive. However, under long-term continuous operation, the light-emitting LD chip and the monitoring PD chip generate high heat, causing the thermally conductive adhesive to thermally expand or even creep and loosen. This changes the stress distribution within the adhesive layer, leading to displacement or loosening of the light-emitting LD chip and the monitoring PD chip. Consequently, the stability of the light-emitting LD chip and the monitoring PD chip after packaging is weakened, affecting the service life of the optical laser. Summary of the Invention

[0004] This invention relates to a TO-can packaging structure for an optical emitting laser, which solves the problem in existing TO-can packaging structures where the light-emitting LD chip and the monitoring PD chip are mostly fixed to the bracket by thermally conductive adhesive. The heat generated during long-term operation causes the thermally conductive adhesive to expand or even creep and loosen, resulting in displacement or loosening of the light-emitting LD chip and the monitoring PD chip, thus weakening the stability of the packaged light-emitting LD chip and the monitoring PD chip.

[0005] In a first aspect, the present invention provides a TO-can package structure for an optically emitting laser, specifically comprising: a bracket, a cap, pins, a thermal pad, an emitting LD chip, a monitoring PD chip, and metal fixing wires. A boss is provided at the center of the upper surface of the bracket, and a thermal pad is mounted on the upper part of the boss. The emitting LD chip and the monitoring PD chip are bonded to the upper surface of the thermal pad using thermally conductive adhesive. A cap is fixedly connected to the upper surface of the bracket outside the boss. Pins are fixedly connected to the boss, penetrating the boss and the bracket. Multiple arched positioning blocks are fixedly connected around the outer perimeter of the thermal pad. Metal fixing wires are welded to the edges of the upper surfaces of both the emitting LD chip and the monitoring PD chip, with the outer ends of the metal fixing wires welded to the upper surfaces of the arched positioning blocks.

[0006] Furthermore, the bracket has a disc structure, and the bracket, boss, and tube cap are on the same axis.

[0007] Furthermore, the outer circumferential surface of the boss is provided with multiple arc-shaped positioning grooves; the lower side of the inner circumferential surface of the tube cap is provided with multiple arc-shaped positioning blocks, the number of arc-shaped positioning blocks is equal to the number of arc-shaped positioning grooves, the arc-shaped positioning blocks and the tube cap are integrally formed, and the arc-shaped positioning blocks can be inserted into the arc-shaped positioning grooves.

[0008] Furthermore, the top surface of the boss is provided with multiple arched positioning grooves, the vertical cross-section of which is arched, and the number of arched positioning grooves is equal to the number of arched positioning blocks.

[0009] Furthermore, an annular pressure plate is provided on the lower side inside the cap, and the annular pressure plate and the cap are integrally formed.

[0010] Furthermore, a flat thermally conductive silicone pad is fixedly connected to the bottom surface of the thermally conductive pad; the bottom of the arched positioning block is an arc-shaped surface, and an arc-shaped thermally conductive silicone pad is fixedly connected to the bottom of the arched positioning block.

[0011] Furthermore, a pressure groove is provided on the outer side of the upper end face of the arched positioning block, and the vertical cross-section of the arched positioning block is arched.

[0012] Furthermore, when the cap is in a sealed state on the upper part of the bracket, the arched positioning block and the arc-shaped thermal conductive silicone pad are located inside the arched positioning groove, and the bottom end face of the annular pressure plate is in close contact with the bottom end face of the pressure groove, and the bottom end face of the planar thermal conductive silicone pad is in close contact with the upper end face of the protrusion.

[0013] This invention provides a TO-can packaging structure for an optically emitting laser, which has the following advantages: This invention, through the combined design of a metal fixing wire and an arched positioning block, allows for the following process during encapsulation: first, the arched positioning block and the curved thermally conductive silicone pad are placed inside the arched positioning groove; then, the light-emitting LD chip and the monitoring PD chip are bonded to the upper surface of the thermally conductive pad using thermally conductive adhesive; next, the metal fixing wire is welded to the edge of the upper surface of the light-emitting LD chip and the monitoring PD chip, and the outer end of the metal fixing wire is welded to the upper surface of the adjacent arched positioning block. This provides a double fixing effect on the light-emitting LD chip and the monitoring PD chip on the boss. Even if the thermally conductive adhesive undergoes thermal expansion or even creep loosening due to the high heat generated by the light-emitting LD chip and the monitoring PD chip, the metal fixing wire and the arched positioning block can firmly fix the light-emitting LD chip and the monitoring PD chip on the boss, effectively preventing displacement or loosening of the light-emitting LD chip and the monitoring PD chip. This significantly improves the stability of the light-emitting LD chip and the monitoring PD chip after encapsulation and extends the service life of the light-emitting laser.

[0014] In addition, by setting an arc-shaped thermally conductive silicone pad at the bottom of the arched positioning block, the arc-shaped thermally conductive silicone pad can fit tightly with the arched positioning groove after the arched positioning block is placed inside the arched positioning groove, thereby improving the stability of the arched positioning block inside the arched positioning groove and thus improving the stability of the light-emitting LD chip and the monitoring PD chip on the boss.

[0015] Furthermore, the design of the arc-shaped positioning groove and the arc-shaped positioning block allows for precise positioning of the cap and the bracket during the encapsulation process. This improves the encapsulation quality of the cap and the bracket. Attached Figure Description

[0016] To more clearly illustrate the technical solution of the present invention, the accompanying drawings of the present invention will be briefly described below.

[0017] In the attached diagram: Figure 1 This paper shows a schematic diagram of the structure of the bracket and the cap after disassembly. Figure 2 This diagram shows the structure of the present application in its packaged state; Figure 3 This paper shows a schematic diagram of the structure of the boss, arched positioning block and curved thermal conductive silicone pad after disassembly. Figure 4 A schematic diagram of the structure of the thermal conductive pad, the light-emitting LD chip, the monitoring PD chip, and the metal fixing wire of this application is shown; Figure 5 A schematic diagram of the structure of the thermal conductive pad, the arched positioning block, and the planar thermal conductive silicone pad of this application is shown; Figure 6 A schematic diagram of the structure of the cap, arc-shaped positioning block and annular pressure plate of this application is shown; Figure 7 The diagram shows a cross-sectional view of the boss, cap, annular pressure plate, arched positioning block, and curved thermal conductive silicone pad of this application.

[0018] List of reference numerals 1. Bracket; 101. Boss; 1011. Arc-shaped positioning groove; 1012. Arch-shaped positioning groove; 2. Pipe cap; 201. Arc-shaped positioning block; 202. Annular pressure plate; 3. Pins; 4. Thermal conductive pad; 401. Arched positioning block; 4011. Pressure groove; 402. Flat thermal conductive silicone pad; 403. Curved thermal conductive silicone pad; 404. Thermal conductive adhesive; 5. Light-emitting diode (LD) chip; 6. Monitoring PD chip; 7. Metal fixing wire. Detailed Implementation

[0019] Example 1: Please refer to Figures 1 to 7 : This invention proposes a TO-can packaging structure for an optically emitting laser, comprising: a bracket 1, a cap 2, pins 3, a thermal pad 4, an emitting LD chip 5, a monitoring PD chip 6, and metal fixing wires 7. A boss 101 is provided at the center of the upper surface of the bracket 1, and a thermal pad 4 is mounted on the top of the boss 101. The emitting LD chip 5 and the monitoring PD chip 6 are bonded to the upper surface of the thermal pad 4 using thermally conductive adhesive 404. The cap 2 is fixedly connected to the upper surface of the bracket 1 outside the boss 101. Pins 3 are fixedly connected to the boss 101, passing through the boss 101 and the bracket 1. Multiple arched positioning blocks 401 are fixedly connected around the outer perimeter of the thermal pad 4. Metal fixing wires 7 are welded to the edges of the upper surfaces of both the emitting LD chip 5 and the monitoring PD chip 6, with the outer ends of the metal fixing wires 7 welded to the upper surfaces of the arched positioning blocks 401. By adopting the above technical solution, during the packaging process, the arched positioning block 401 and the arc-shaped thermal conductive silicone pad 403 are first placed inside the arched positioning groove 1012. Then, the light-emitting LD chip 5 and the monitoring PD chip 6 are bonded to the upper surface of the thermal conductive pad 4 using thermally conductive adhesive 404. Next, the metal fixing wire 7 is welded to the edge of the upper surface of the light-emitting LD chip 5 and the monitoring PD chip 6, and the outer end of the metal fixing wire 7 is welded to the upper surface of the adjacent arched positioning block 401. This provides a double fixing effect for the light-emitting LD chip 5 and the monitoring PD chip 6 on the boss 101. Even if the thermally conductive adhesive 404 undergoes thermal expansion or even creep relaxation due to the high heat generated by the light-emitting LD chip 5 and the monitoring PD chip 6, the light-emitting LD chip 5 and the monitoring PD chip 6 can still be firmly fixed to the boss 101 by the metal fixing wire 7 and the arched positioning block 401. Therefore, it can effectively prevent the light-emitting LD chip 5 and the monitoring PD chip 6 from shifting or loosening, thereby improving the stability of the light-emitting LD chip 5 and the monitoring PD chip 6 after packaging.

[0020] The bracket 1 has a disc structure. The bracket 1, the boss 101 and the cap 2 are on the same axis for coaxial encapsulation.

[0021] The outer circumferential surface of the boss 101 is provided with multiple arc-shaped positioning grooves 1011; the lower side of the inner circumferential surface of the cap 2 is provided with multiple arc-shaped positioning blocks 201, the number of arc-shaped positioning blocks 201 is equal to the number of arc-shaped positioning grooves 1011, the arc-shaped positioning blocks 201 and the cap 2 are integrally formed, and the arc-shaped positioning blocks 201 can be inserted into the arc-shaped positioning grooves 1011. By adopting the above technical solution, when the cap 2 and the bracket 1 are packaged, the precise positioning of the cap 2 and the bracket 1 can be achieved through the insertion and cooperation of the arc-shaped positioning block 201 and the arc-shaped positioning groove 1011, thus improving the packaging quality of the cap 2 and the bracket 1.

[0022] The top surface of the boss 101 is provided with multiple arched positioning grooves 1012. The vertical cross section of the arched positioning grooves 1012 is arched, and the number of arched positioning grooves 1012 is equal to the number of arched positioning blocks 401.

[0023] An annular pressure plate 202 is provided on the lower side of the inside of the pipe cap 2. The annular pressure plate 202 and the pipe cap 2 are integrally formed to ensure that the annular pressure plate 202 has good strength.

[0024] A flat thermally conductive silicone pad 402 is fixedly connected to the bottom end face of the thermally conductive pad 4; the bottom of the arched positioning block 401 is an arc-shaped surface, and an arc-shaped thermally conductive silicone pad 403 is fixedly connected to the bottom of the arched positioning block 401 to transfer the heat on the arched positioning block 401 to the boss 101. Moreover, by setting multiple arched positioning blocks 401, the heat dissipation efficiency of the thermally conductive pad 4 can be improved.

[0025] An arched positioning block 401 has a pressure groove 4011 on the outer side of its upper end face. The vertical cross section of the arched positioning block 401 is arched so that it can fit into the arched positioning groove 1012. Moreover, the arched design makes it easier for the arched positioning block 401 and the arc-shaped thermal conductive silicone pad 403 to be placed inside the arched positioning groove 1012.

[0026] When the cap 2 is in the encapsulated state on the upper part of the bracket 1, the arched positioning block 401 and the arc-shaped thermal conductive silicone pad 403 are located inside the arched positioning groove 1012, and the bottom end face of the annular pressure plate 202 is in close contact with the bottom end face of the pressure groove 4011, and the bottom end face of the planar thermal conductive silicone pad 402 is in close contact with the upper end face of the boss 101, ensuring the thermal conductivity of the planar thermal conductive silicone pad 402.

[0027] The working principle of this invention is as follows: During packaging, the arched positioning block 401 and the arc-shaped thermal conductive silicone pad 403 are first placed inside the arched positioning groove 1012 so that the arc-shaped thermal conductive silicone pad 403 is in close contact with the arched positioning groove 1012. Then, the light-emitting LD chip 5 and the monitoring PD chip 6 are bonded to the upper end face of the thermal pad plate 4 with thermal adhesive 404. Next, the metal fixing wire 7 is welded to the edge of the upper end face of the light-emitting LD chip 5 and the monitoring PD chip 6. Then, the outer end of the metal fixing wire 7 is welded to the upper end face of the adjacent arched positioning block 401. Subsequently, the cap 2 is fixedly connected to the upper surface of the bracket 1. During this process, the cap 2 will be fitted onto the outside of the boss 101 from top to bottom, and will be inserted into the arc-shaped positioning block 201 and the arc-shaped positioning groove 1011 to achieve precise positioning of the cap 2 and the bracket 1. Then, when the bottom surface of the cap 2 contacts the upper surface of the bracket 1, the bottom surface of the annular pressure plate 202 will be in close contact with the bottom surface of the pressure groove 4011, so that the heat-conducting pad 4 and the arched positioning block 401 can be effectively fixed on the boss 101. Moreover, due to the light-emitting LD chip 5 and the monitoring PD chip All 6 are fixedly connected to the arched positioning block 401 via metal fixing wire 7. Therefore, the light-emitting LD chip 5 and the monitoring PD chip 6 can be doubly fixed on the boss 101. Even if the thermal conductive adhesive 404 undergoes thermal expansion or even creep loosening due to the high heat generated by the light-emitting LD chip 5 and the monitoring PD chip 6, it can still be firmly fixed to the boss 101 by the metal fixing wire 7 and the arched positioning block 401, preventing the light-emitting LD chip 5 and the monitoring PD chip 6 from shifting or loosening. This improves the stability of the light-emitting LD chip 5 and the monitoring PD chip 6 after packaging and extends the service life of the light-emitting laser. Furthermore, when the bottom end face of the tube cap 2 contacts the top end face of the bracket 1, the bottom end face of the planar thermal conductive silicone pad 402 will be in close contact with the top end face of the boss 101 to transfer the heat from the thermal pad 4 to the boss 101, facilitating heat dissipation for the light-emitting LD chip 5 and the monitoring PD chip 6. Finally, fixing the tube cap 2 to the top end face of the bracket 1 completes the TO-can packaging of the light-emitting laser.

Claims

1. A TO-can packaging structure for an optically emitting laser, comprising: The bracket (1), cap (2), pins (3), thermal pad (4), light-emitting LD chip (5), monitoring PD chip (6), and metal fixing wire (7) are characterized in that a boss (101) is provided at the center of the upper end face of the bracket (1), and a thermal pad (4) is installed on the upper part of the boss (101); the light-emitting LD chip (5) and the monitoring PD chip (6) are bonded to the upper end face of the thermal pad (4) by thermally conductive adhesive (404); the upper end face of the bracket (1) A tube cap (2) is fixedly connected to the outside of the boss (101); a pin (3) is fixedly connected to the boss (101), and the pin (3) passes through the boss (101) and the bracket (1); multiple arched positioning blocks (401) are fixedly connected around the outside of the heat-conducting pad (4); metal fixing wires (7) are welded to the upper edge of the light-emitting LD chip (5) and the monitoring PD chip (6), and the outer end of the metal fixing wire (7) is welded to the upper surface of the arched positioning block (401).

2. The TO-can packaging structure for an optical emitting laser according to claim 1, characterized in that: The bracket (1) is a disc structure, and the bracket (1), the boss (101) and the cap (2) are on the same axis.

3. The TO-can packaging structure for an optically emitting laser according to claim 1, characterized in that: The outer circumferential surface of the boss (101) is provided with multiple arc-shaped positioning grooves (1011); the lower side of the inner circumferential surface of the cap (2) is provided with multiple arc-shaped positioning blocks (201), the number of arc-shaped positioning blocks (201) is equal to the number of arc-shaped positioning grooves (1011), the arc-shaped positioning blocks (201) and the cap (2) are integrally formed, and the arc-shaped positioning blocks (201) can be inserted into the arc-shaped positioning grooves (1011).

4. The TO-can packaging structure for an optically emitting laser according to claim 1, characterized in that: The top surface of the boss (101) is provided with a plurality of arched positioning grooves (1012). The vertical cross section of the arched positioning grooves (1012) is arched, and the number of arched positioning grooves (1012) is equal to the number of arched positioning blocks (401).

5. The TO-can packaging structure for an optically emitting laser according to claim 4, characterized in that: The lower inside of the cap (2) is provided with an annular pressure plate (202), and the annular pressure plate (202) and the cap (2) are integrally formed.

6. The TO-can packaging structure for an optically emitting laser according to claim 5, characterized in that: The bottom surface of the thermal pad (4) is fixedly connected to a flat thermally conductive silicone pad (402); the bottom of the arched positioning block (401) is an arc-shaped surface, and the bottom of the arched positioning block (401) is fixedly connected to an arc-shaped thermally conductive silicone pad (403).

7. The TO-can packaging structure for an optically emitting laser according to claim 6, characterized in that: The upper surface of the arched positioning block (401) is provided with a pressure groove (4011), and the vertical cross section of the arched positioning block (401) is arched.

8. The TO-can packaging structure for an optically emitting laser according to claim 7, characterized in that: When the cap (2) is in a sealed state on the upper part of the bracket (1), the arched positioning block (401) and the arc-shaped thermal conductive silicone pad (403) are located inside the arched positioning groove (1012), and the bottom end face of the annular pressure plate (202) is in close contact with the bottom end face of the pressure groove (4011), and the bottom end face of the planar thermal conductive silicone pad (402) is in close contact with the upper end face of the boss (101).

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