A CPO silicon photonics engine capable of high-temperature reflow soldering

Abstract

This utility model relates to a CPO silicon photonics engine capable of high-temperature reflow soldering. A PCB board covers and fixes the lower opening of the housing. An electrical chip, a silicon photonics chip, and a fiber optic array are arranged inside the housing. The electrical chip is located on the upper surface of the PCB board and electrically connected to it. The silicon photonics chip is located on the upper surface of the electrical chip and electrically connected to it. The fiber optic array is fixed to and coupled to the side of the silicon photonics chip. An upper heat storage block is provided on the top wall of the housing above the fiber optic array. The gap between the upper heat storage block and the fiber optic array is filled with upper phase change thermally conductive adhesive. A lower heat storage block is provided on the upper surface of the PCB board below the fiber optic array. The gap between the lower heat storage block and the fiber optic array is filled with lower phase change thermally conductive adhesive. The housing is made of titanium alloy, and the lower and upper heat storage blocks are made of zinc alloy. The beneficial effect is that it ensures the fiber optic array maintains a temperature below 150°C in the hot air during high-temperature reflow soldering, thus allowing the use of ordinary fiber optic arrays and reducing costs.

Description

Technical Field

[0001] This utility model relates to the field of CPO silicon photonics engine technology, specifically to a CPO silicon photonics engine that can be reflow soldered at high temperatures. Background Technology

[0002] Traditional CPO silicon photonics engines use high-temperature reflow soldering to weld electrode posts on the underside of the PCB board to the main board of the switch. The solder used is SAC305 (96.5% tin, 3% silver, 0.5% copper, melting point 217℃~221℃). The peak temperature of the high-temperature reflow soldering is 260℃±5℃, and the duration is 10s. Ordinary fiber arrays cannot withstand the high temperature of 260℃±5℃ for a short time. Complex optical systems such as lenses need to be designed between the silicon photonics chip and the fiber array, resulting in high costs. The lens is still in the silicon photonics engine. The fixed lens is generally glued. The glue cannot withstand the high temperature of 260℃±5℃ for a short time, which causes optical path displacement, yellowing and blackening of the glue and reduced light transmittance. Utility Model Content

[0003] The technical problem to be solved by this invention is to provide a CPO silicon photonics engine that can be reflow soldered at high temperatures, so as to overcome the shortcomings of the prior art.

[0004] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A high-temperature reflow solderable CPO silicon photonics engine includes: a housing and a PCB board that covers and fixes to the lower opening of the housing. An electrical chip, a silicon photonics chip, and an optical fiber array are arranged inside the housing. The electrical chip is located on the upper surface of the PCB board and electrically connected to it. The silicon photonics chip is located on the upper surface of the electrical chip and electrically connected to it. The optical fiber array is fixed to and coupled to the side of the silicon photonics chip. An upper heat storage block is provided on the top wall of the housing above the optical fiber array. The gap between the upper heat storage block and the optical fiber array is filled with upper phase change thermal conductive adhesive. A lower heat storage block is provided on the upper surface of the PCB board below the optical fiber array. The gap between the lower heat storage block and the optical fiber array is filled with lower phase change thermal conductive adhesive. The housing is made of titanium alloy, and the lower and upper heat storage blocks are made of zinc alloy.

[0005] The beneficial effects of this utility model are: by using a titanium alloy shell, a zinc alloy lower heat storage block and an upper heat storage block, and filling with upper and lower phase change thermal conductive adhesives, the three can work together to ensure that the fiber array maintains a temperature below 150°C in the hot air of high-temperature reflow soldering, thereby allowing the use of ordinary fiber arrays and greatly reducing the cost of CPO silicon photonics engines.

[0006] Based on the above technical solution, the present invention can be further improved as follows.

[0007] Furthermore, multiple baffle blocks are arranged around the upper phase change thermal conductive adhesive in the gap between the upper thermal storage block and the fiber array. The multiple baffle blocks keep the upper phase change thermal conductive adhesive in a closed annular space, and the height of the baffle blocks is smaller than the height of the gap between the upper thermal storage block and the fiber array.

[0008] The further beneficial effects of adopting the above are as follows: by using multiple adhesive blocks, the viscous liquid phase change thermal conductive adhesive can be prevented from flowing to other areas at high temperatures, so that the upper phase change thermal conductive adhesive can always be in contact with the upper heat storage block and the optical fiber array, thereby achieving heat dissipation at various temperatures.

[0009] Furthermore, the upward projection of a portion of the silicon photonic chip falls onto the upper heat storage block, and the upper phase change thermal conductive adhesive fills the gap between the silicon photonic chip and the upper heat storage block; the height of the adhesive block is smaller than the height of the gap between the upper heat storage block and the silicon photonic chip, and the fiber array and the silicon photonic chip are fixed together with adhesive.

[0010] The further beneficial effects of adopting the above are: the upper heat storage block and the upper phase change thermal conductive adhesive can dissipate heat from the silicon photonic chip to prevent the silicon photonic chip temperature from becoming too high.

[0011] Furthermore, the upper surface of the cover plate in the fiber array is at the same height as the upper surface of the silicon photonic chip.

[0012] The further beneficial effect of adopting the above is that the thickness of the phase change thermal conductive adhesive above the fiber array can be made consistent with the thickness of the phase change thermal conductive adhesive above the silicon photonic chip.

[0013] Furthermore, a groove is formed on the upper surface of the lower heat storage block, and the lower phase change thermal conductive adhesive is located in the groove on the upper surface of the lower heat storage block.

[0014] The further beneficial effects of adopting the above are: it can prevent the viscous liquid phase change thermal conductive adhesive from flowing to other areas at high temperatures, so that the lower phase change thermal conductive adhesive can always be in contact with the lower heat storage block and the optical fiber array, thereby achieving heat dissipation at various temperatures.

[0015] Furthermore, the projection of the suspended area of ​​the silicon photonics chip falls into the groove of the lower heat storage block, and the lower phase change thermal conductive adhesive fills the gap between the silicon photonics chip and the lower heat storage block.

[0016] The further beneficial effects of adopting the above are: the lower heat storage block and the lower phase change thermal conductive adhesive can dissipate heat from the silicon photonic chip to prevent the silicon photonic chip temperature from becoming too high.

[0017] Furthermore, the lower surface of the substrate in the fiber array is at the same height as the lower surface of the silicon photonic chip.

[0018] The further beneficial effect of adopting the above is that the thickness of the lower phase change thermal conductive adhesive under the fiber array can be made consistent with the thickness of the lower phase change thermal conductive adhesive under the silicon photonic chip.

[0019] Furthermore, through holes are opened on the side wall of the housing to allow the pigtails in the fiber array to pass through, and the through holes are filled with heat-insulating soft silicone.

[0020] Furthermore, the surface roughness of the shell is less than R0.8μm.

[0021] The further beneficial effects of the above-mentioned method are as follows: polishing the surface of the titanium alloy can reduce the roughness to less than R0.8μm, which further reduces the contact area with hot air. In addition, the low thermal conductivity and high specific heat capacity result in a very slow heating process.

[0022] Furthermore, the thickness of the upper thermal storage block is 2mm to 3mm, the thickness of the lower thermal storage block is 1.5mm to 2mm, and the thickness of the upper and lower phase change thermal conductive adhesives is 0.5mm ± 0.1mm.

[0023] Furthermore, the thermal conductivity of titanium alloy is 7 W / m·K, and its specific heat capacity is 500 J / kg·K; the specific heat capacity of zinc alloy is 3850 J / kg·K. Attached Figure Description

[0024] Figure 1 This is a structural diagram of the CPO silicon photonic engine that can be reflow soldered at high temperatures in this utility model.

[0025] The attached diagram lists the components represented by each number as follows: 1. Housing, 110. Via, 2. PCB board, 3. Electrical chip, 4. Silicon photonics chip, 5. Fiber optic array, 6. Upper heat storage block, 7. Upper phase change thermal conductive adhesive, 8. Lower heat storage block, 810. Groove, 9. Lower phase change thermal conductive adhesive, 10. Adhesive block, 11. Thermal insulation soft silicone. Detailed Implementation

[0026] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0027] Example 1 like Figure 1 As shown, a CPO silicon photonic engine capable of high-temperature reflow soldering includes: The system consists of a housing 1 and a PCB board 2. The PCB board 2 covers the lower opening of the housing 1 and is fixed to the housing 1. High-temperature reflow soldering is mainly used to ensure that the electrode posts on the lower surface of the PCB board 2 are soldered to the main board of the switch using hot air. The solder used is SAC305. Inside the housing 1, there are electrical chips 3, silicon photonic chips 4, and fiber arrays 5. The electrical chips 3 are located on the upper surface of the PCB board 2 and are electrically connected to the PCB board 2. That is, when the electrode posts of the electrical chips 3 are soldered to the PCB board 2, solder with a temperature higher than 260°C is used, such as Au80Sn20, which has a melting point of 280°C. The silicon photonic chips 4 are located on the upper surface of the electrical chips 3 and are electrically connected to the electrical chips 3. When the electrode posts of the silicon photonic chips 4 are soldered to the electrical chips 3, solder with a temperature higher than 260°C is used, such as Au80Sn20, which has a melting point of 280°C. The fiber optic array 5 is fixed to the side of the silicon photonic chip 4 and coupled to the silicon photonic chip 4. An upper heat storage block 6 is provided on the top wall of the housing 1 above the fiber optic array 5. The gap between the upper heat storage block 6 and the fiber optic array 5 is filled with upper phase change thermal conductive adhesive 7. A lower heat storage block 8 is provided on the upper surface of the PCB board 2 below the fiber optic array 5. The gap between the lower heat storage block 8 and the fiber optic array 5 is filled with lower phase change thermal conductive adhesive 9. The housing 1 is made of titanium alloy, the lower heat storage block 8 is made of zinc alloy, and the upper heat storage block 6 is made of zinc alloy. The titanium alloy shell 1 has a low thermal conductivity and a high specific heat capacity, which results in a very slow temperature rise. The lower heat storage block 8 and the upper heat storage block 6, made of zinc alloy, have a large specific heat capacity, which can absorb a large amount of heat in a short time and further slow down the temperature of the fiber array 5 area. The upper phase change thermal conductive adhesive 7 and the lower phase change thermal conductive adhesive 9 absorb heat at high temperatures, changing from a solid state at room temperature to a viscous liquid state. This phase change process absorbs a large amount of heat, further slowing down the temperature of the fiber array 5 region. By using a titanium alloy housing 1, a zinc alloy lower heat storage block 8 and an upper heat storage block 6, and filling with upper phase change thermal conductive adhesive 7 and lower phase change thermal conductive adhesive 9, the three components work together to ensure that the fiber array 5 maintains a temperature below 150°C in the hot air of high-temperature reflow soldering. This allows the use of a standard fiber array 5, greatly reducing the cost of the CPO silicon photonics engine.

[0028] Example 2 like Figure 1 As shown, this embodiment is a further improvement on embodiment 1, as detailed below: Multiple baffle blocks 10 are arranged around the upper phase change thermal conductive adhesive 7 in the gap between the upper heat storage block 6 and the fiber array 5. The baffle blocks 10 can be made of glass. The multiple baffle blocks 10 keep the upper phase change thermal conductive adhesive 7 in a closed annular space. The height of the baffle blocks 10 is smaller than the height of the gap between the upper heat storage block 6 and the fiber array 5. The cooperation of multiple baffle blocks 10 can prevent the viscous liquid phase change thermal conductive adhesive from flowing to other areas at high temperatures, so that the upper phase change thermal conductive adhesive 7 can always be in contact with the upper heat storage block 6 and the fiber array 5, and achieve heat dissipation at various temperatures.

[0029] Furthermore, the upward projection of a portion of the silicon photonic chip 4 falls onto the upper heat storage block 6. The upper phase change thermally conductive adhesive 7 fills the gap between the silicon photonic chip 4 and the upper heat storage block 6. Among the multiple adhesive blocks 10, some adhesive blocks 10 are located on the silicon photonic chip 4, some are located on the fiber array 5, and some are located between the silicon photonic chip 4 and the fiber array 5. The height of the adhesive blocks 10 is smaller than the height of the gap between the upper heat storage block 6 and the silicon photonic chip 4. The fiber array 5 and the silicon photonic chip 4 are fixed together with adhesive. The upper heat storage block 6 and the upper phase change thermally conductive adhesive 7 can reduce the temperature of the adhesive between the fiber array 5 and the silicon photonic chip 4, preventing them from falling off or shifting. At the same time, the upper heat storage block 6 and the upper phase change thermally conductive adhesive 7 can also dissipate heat from the silicon photonic chip 4 to prevent the silicon photonic chip 4 from overheating.

[0030] The upper surface of the cover plate in the fiber array 5 is at the same height as the upper surface of the silicon photonic chip 4, so that the thickness of the upper phase change thermal conductive adhesive 7 on the fiber array 5 is the same as the thickness of the upper phase change thermal conductive adhesive 7 on the silicon photonic chip 4.

[0031] Example 3 like Figure 1 As shown, this embodiment is a further improvement on embodiment 1 or 2, as detailed below: A groove 810 is formed on the upper surface of the lower heat storage block 8, and the lower phase change thermal conductive adhesive 9 is located in the groove 810 on the upper surface of the lower heat storage block 8. This can prevent the viscous liquid phase change thermal conductive adhesive from flowing to other areas at high temperatures, so that the lower phase change thermal conductive adhesive 9 can always be in contact with the lower heat storage block 8 and the fiber array 5, and achieve heat dissipation at various temperatures.

[0032] Furthermore, the projection of the suspended area of ​​the silicon photonic chip 4 falls into the groove 810 of the lower heat storage block 8. The lower phase change thermal conductive adhesive 9 fills the gap between the silicon photonic chip 4 and the lower heat storage block 8. The lower heat storage block 8 and the lower phase change thermal conductive adhesive 9 can reduce the temperature of the adhesive between the fiber array 5 and the silicon photonic chip 4, preventing them from falling off or shifting. At the same time, the lower heat storage block 8 and the lower phase change thermal conductive adhesive 9 can also dissipate heat from the silicon photonic chip 4 to prevent the silicon photonic chip 4 from overheating.

[0033] The lower surface of the substrate in the fiber array 5 is at the same height as the lower surface of the silicon photonic chip 4, so that the thickness of the lower phase change thermal conductive adhesive 9 below the fiber array 5 is the same as the thickness of the lower phase change thermal conductive adhesive 9 below the silicon photonic chip 4.

[0034] Example 4 like Figure 1 As shown, this embodiment is a further improvement on embodiment 1, 2, or 3, as detailed below: A through hole 110 is provided on the side wall of the housing 1 for the pigtails in the fiber array 5 to pass through, and the through hole 110 is filled with heat-insulating soft silicone 11.

[0035] Example 5 like Figure 1 As shown, this embodiment is a further improvement on embodiment 1, 2, 3, or 4, as detailed below: The surface roughness of the shell 1 is less than R0.8μm. Polishing the titanium alloy surface can reduce the roughness to less than R0.8μm, which further reduces the contact area with hot air. In addition, the low thermal conductivity and high specific heat capacity result in very slow heating.

[0036] Example 6 like Figure 1 As shown, this embodiment is a further improvement on any one of embodiments 1 to 5, as detailed below: The thickness of the upper thermal storage block 6 is 2mm to 3mm, the thickness of the lower thermal storage block 8 is 1.5mm to 2mm, and the thickness of the upper phase change thermal conductive adhesive 7 and the lower phase change thermal conductive adhesive 9 is 0.5mm ± 0.1mm.

[0037] The thermal conductivity of titanium alloy is 7 W / m·K, and its specific heat capacity is 500 J / kg·K; the specific heat capacity of zinc alloy is 3850 J / kg·K.

[0038] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A CPO silicon photonic engine capable of high-temperature reflow soldering, characterized in that, include: The housing (1) and the PCB board (2) that covers and fixes the lower opening of the housing (1) are provided. The housing (1) contains an electrical chip (3), a silicon photonic chip (4), and an optical fiber array (5). The electrical chip (3) is located on the upper surface of the PCB board (2) and is electrically connected to it. The silicon photonic chip (4) is located on the upper surface of the electrical chip (3) and is electrically connected to it. The optical fiber array (5) is fixed to and coupled to the side of the silicon photonic chip (4). The top wall of the housing (1) is... An upper heat storage block (6) is provided above the fiber array (5), and the gap between the upper heat storage block (6) and the fiber array (5) is filled with upper phase change thermal conductive adhesive (7). A lower heat storage block (8) is provided on the upper surface of the PCB board (2) below the fiber array (5), and the gap between the lower heat storage block (8) and the fiber array (5) is filled with lower phase change thermal conductive adhesive (9). The shell (1) is made of titanium alloy, and the lower heat storage block (8) and the upper heat storage block (6) are made of zinc alloy.

2. The CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 1, characterized in that, Multiple baffle blocks (10) are arranged around the upper phase change thermal conductive adhesive (7) in the gap between the upper heat storage block (6) and the fiber array (5). The multiple baffle blocks (10) keep the upper phase change thermal conductive adhesive (7) in a closed annular space. The height of the baffle blocks (10) is smaller than the height of the gap between the upper heat storage block (6) and the fiber array (5).

3. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 2, characterized in that, The upward projection of a portion of the silicon photonic chip (4) falls on the upper heat storage block (6), and the upper phase change thermal conductive adhesive (7) fills the gap between the silicon photonic chip (4) and the upper heat storage block (6); the height of the adhesive block (10) is smaller than the height of the gap between the upper heat storage block (6) and the silicon photonic chip (4), and the fiber array (5) is fixed to the silicon photonic chip (4) with adhesive.

4. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 1, 2, or 3, characterized in that, The upper surface of the cover plate in the fiber array (5) is at the same height as the upper surface of the silicon photonic chip (4).

5. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 1, characterized in that, A groove (810) is formed on the upper surface of the lower heat storage block (8), and the lower phase change thermal conductive adhesive (9) is located in the groove (810) on the upper surface of the lower heat storage block (8).

6. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 5, characterized in that, The projection of the suspended area of ​​the silicon photonic chip (4) falls into the groove (810) of the lower heat storage block (8), and the lower phase change thermal conductive adhesive (9) fills the gap between the silicon photonic chip (4) and the lower heat storage block (8).

7. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 1, 5, or 6, characterized in that, The lower surface of the substrate in the fiber array (5) is at the same height as the lower surface of the silicon photonic chip (4).

8. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 1, characterized in that, The housing (1) has a through hole (110) on its side wall for the pigtails in the fiber array (5) to pass through, and the through hole (110) is filled with heat-insulating soft silicone (11).

9. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 1, characterized in that, The surface roughness of the housing (1) is less than R0.8μm.

10. A CPO silicon photonic engine capable of high-temperature reflow soldering according to claim 1, characterized in that, The thickness of the upper heat storage block (6) is 2mm to 3mm, the thickness of the lower heat storage block (8) is 1.5mm to 2mm, and the thickness of the upper phase change thermal conductive adhesive (7) and the lower phase change thermal conductive adhesive (9) is 0.5mm ± 0.1mm.

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