A method for manufacturing an els optical module

Abstract

The application provides a preparation method of an ELS optical module, which comprises the following steps: selecting an FA substrate, an optical fiber, an adhesive material and an auxiliary material; processing the FA substrate, the optical fiber, the adhesive material and the auxiliary material to obtain an FA preform; fixing a heat-conducting substrate on the inner wall of an ELS shell and fixing a laser array on the surface of the heat-conducting substrate; aligning the FA preform with the laser array and fixing the FA preform on the bonding area of the heat-conducting substrate; fixing the optical fiber on the FA preform and leading the optical fiber out of the ELS shell; installing a TEC temperature control chip, a driving circuit and a heat dissipation component; sealing the ELS shell as a whole and performing performance testing to obtain the ELS optical module. The application solves the technical problems of the existing preparation process of the ELS optical module, such as large occupied space, complex assembly, poor thermal stability, large fluctuation of optical path loss, high loss and disordered optical fiber arrangement.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to a method for fabricating an ELS optical module. Background Technology

[0002] With the rapid development of large-scale artificial intelligence (AI) models and hyperscale data centers, co-packaged optics (CPO) architecture is gradually becoming mainstream. Enhanced laser source (ELS) optical modules, as core devices that provide high-power continuous light sources for silicon photonics engines, are rapidly evolving towards multi-channel, high-power, ultra-miniaturization, and high heat dissipation reliability.

[0003] Currently, multi-channel ELS optical modules in the industry generally use a combination of multiple sets of traditional MT ferrules to achieve multi-channel fiber optic arrangement and optical path exit at the interface between the laser array and the external fiber optic path. However, the above-mentioned multi-set MT ferrule combination scheme has the following drawbacks:

[0004] 1. Large space occupation and difficulty in miniaturization of modules: MT pins come with plastic base, positioning pins and shell structure. Due to the limited size of the pluggable package, the space left for heat dissipation structure, TEC temperature control chip and drive circuit is severely squeezed, making it impossible to achieve module thinning and miniaturization.

[0005] 2. Complex assembly and low mass production efficiency: Multiple sets of MT pins need to be independently positioned, optically coupled channel by channel, and cured with glue multiple times. The assembly process is complicated, relying on manual labor or high-precision semi-automatic equipment. The production cycle is slow, the mass production cost is high, and the yield is difficult to improve.

[0006] 3. Poor thermal stability and large fluctuations in optical path loss: The MT ferrule has a high coefficient of thermal expansion. When the ELS optical module operates at high power, the internal temperature rises significantly. The plastic ferrule deforms due to heat, which can cause the optical fiber core and the laser optical path to be misaligned, resulting in increased insertion loss and poor channel power consistency. After long-term high and low temperature cycling, optical path mismatch and device aging failure are also likely to occur.

[0007] 4. Multiple interfaces and high inherent loss: Multiple MT splicing has multiple optical docking interfaces, air gaps and end face reflection superposition, resulting in high overall optical path insertion loss, which is not conducive to the efficient transmission of high-power optical signals in ELS and is also difficult to meet the requirements of high return loss.

[0008] 5. Disorganized fiber optic cable arrangement and high stress: Multiple sets of MT pigtails are led out in parallel, with limited bending radius and disordered arrangement. During module vibration and insertion / removal, the fiber optic cable is prone to additional stress, which reduces the overall reliability and service life of the machine and increases the difficulty of subsequent maintenance. Summary of the Invention

[0009] This application provides a method for fabricating an ELS optical module, aiming to solve the technical problems of existing ELS optical module fabrication processes, which involve large space occupation, complex assembly, poor thermal stability, large fluctuations in optical path loss, high loss, and messy fiber arrangement due to the use of multiple sets of traditional MT ferrules.

[0010] In a first aspect, embodiments of this application provide a method for fabricating an ELS optical module, the method comprising:

[0011] FA substrate, optical fiber, adhesive material and auxiliary materials are selected, wherein the auxiliary materials include cover plate, thermally conductive substrate and laser array;

[0012] FA preforms are obtained by using the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials.

[0013] The thermally conductive substrate is fixed to the inner wall of the ELS housing, and the laser array is fixed to the surface of the thermally conductive substrate;

[0014] Align the FA preform with the laser array and fix the FA preform in the bonding area of ​​the thermally conductive substrate;

[0015] Secure the optical fiber on the FA preform and lead the optical fiber out from the ELS housing;

[0016] Install the TEC temperature control chip, drive circuit, and heat dissipation components;

[0017] The ELS housing is sealed as a whole, and performance tests are performed to prepare the ELS optical module.

[0018] Optionally, the process of obtaining an FA preform by applying the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials includes:

[0019] V-grooves are etched on the FA substrate;

[0020] The optical fiber is fixed within the V-groove of the FA substrate;

[0021] The cover plate is pressed onto the FA substrate to prepare a 2D-FA preform;

[0022] The 2D-FA preform is subjected to end face treatment and coating.

[0023] Optionally, aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate includes:

[0024] Clean the 2D-FA preform;

[0025] The 2D-FA preform is placed in the bonding area of ​​the thermally conductive substrate;

[0026] Adjust the 2D-FA preform so that each fiber core of the 2D-FA preform is aligned with the light-emitting port of the corresponding laser array;

[0027] Apply curing adhesive to the edges of the 2D-FA preform;

[0028] A curing adhesive is applied to the bonding area between the 2D-FA preform and the thermally conductive substrate, and then cured at a constant temperature using a UV curing lamp.

[0029] Optionally, the process of obtaining an FA preform by applying the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials includes:

[0030] V-grooves are etched on the FA substrate;

[0031] The optical fiber is fixed within the V-groove of the FA substrate;

[0032] The cover plate is pressed onto the FA substrate to prepare two 2D-FA preforms.

[0033] Preparation of silicon separator;

[0034] The two 2D-FA preforms are stacked through the silicon separator to prepare a 3D-FA preform.

[0035] Optionally, aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate includes:

[0036] Clean the 3D-FA preform;

[0037] The 3D-FA preform is placed in the bonding area of ​​the thermally conductive substrate;

[0038] Adjust the 3D-FA preform so that each fiber core of the 3D-FA preform is aligned with the light-emitting port of the corresponding laser array;

[0039] Apply curing adhesive to the edges of the 3D-FA preform;

[0040] A curing adhesive is applied to the bonding area between the 3D-FA preform and the thermally conductive substrate, and then cured at a constant temperature using a UV curing lamp.

[0041] Optionally, before aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate, the method further includes:

[0042] Select a microlens array;

[0043] Clean the microlens array;

[0044] The microlens array is placed between the laser array and the bonding area of ​​the thermally conductive substrate;

[0045] Adjust the position of the microlens array so that it is aligned with the light-emitting port of the corresponding laser array and the optical fiber channel;

[0046] The microlens array is fixed on the thermally conductive substrate;

[0047] Aligning the FA preform with the laser array includes:

[0048] The position of the FA preform is adjusted so that each fiber core of the FA preform is aligned with the light-emitting port of the corresponding laser array through the microlens array.

[0049] Optionally, fixing the thermally conductive substrate to the inner wall of the ELS housing includes:

[0050] Clean the thermally conductive substrate;

[0051] A mating area matching the FA preform is etched on the surface of the thermally conductive substrate;

[0052] Thermal grease is applied to the back side of the bonding area of ​​the thermally conductive substrate;

[0053] The thermally conductive substrate is fixed to the inner wall of the ELS housing.

[0054] Optionally, fixing the laser array to the surface of the thermally conductive substrate includes:

[0055] Clean the laser array;

[0056] The laser array is fixed on the surface of the thermally conductive substrate;

[0057] Adjust the laser array so that the emission port of the laser array corresponds to the optical fiber channel of the FA preform.

[0058] Optionally, the mounting of the TEC temperature control chip, drive circuit, and heat dissipation assembly includes:

[0059] The TEC temperature control chip is installed between the laser array and the FA preform, with the cold end of the TEC temperature control chip attached to the back of the laser array and the hot end of the TEC temperature control chip attached to the thermally conductive substrate.

[0060] The driving circuit is fixed to the inner wall of the ELS housing, and the driving circuit, the laser array, and the TEC temperature control chip are connected by gold wire bonding.

[0061] One end of the heat dissipation component is attached to the thermally conductive substrate, and the other end of the heat dissipation component is attached to the inner wall of the ELS housing;

[0062] Connect the pins of the TEC temperature control chip, the drive circuit, and the ELS optical module.

[0063] Optionally, the process of sealing the ELS housing and performing performance testing includes:

[0064] Apply sealant to the seams of the ELS housing and fasten the housing cover.

[0065] Optical performance testing, thermal performance testing, and reliability testing are performed on the ELS optical module.

[0066] The optical performance tests include insertion loss testing, return loss testing, and power flatness testing, while the reliability tests include vibration testing and insertion / removal testing.

[0067] This application provides a method for fabricating an ELS optical module. The method includes: selecting an FA substrate, optical fiber, adhesive material, and auxiliary materials, the auxiliary materials including a cover plate, a thermally conductive substrate, and a laser array; processing the FA preform using the FA substrate, optical fiber, adhesive material, and auxiliary materials; fixing the thermally conductive substrate to the inner wall of the ELS housing and fixing the laser array to the surface of the thermally conductive substrate; aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate; fixing the optical fiber on the FA preform and leading the optical fiber out from the ELS housing; installing a TEC temperature control chip, a drive circuit, and a heat dissipation component; sealing the ELS housing and performing performance testing to fabricate the ELS optical module. In this application, a single multi-dimensional fiber array is used to replace multiple sets of MT ferrules to achieve miniaturization of the space occupied; alignment of the FA preform with the laser array is achieved, reducing optical path loss and improving channel consistency; FA substrate with a thermal expansion coefficient matching that of the laser array and the thermally conductive substrate is selected to improve thermal stability; the assembly process is simplified and mass production costs are reduced by using FA preform alignment and ELS optical module curing process; FA substrate is bonded to the thermally conductive substrate, the thermally conductive substrate integrates heat insulation trenches, and the optical fiber is neatly led out, thereby improving heat dissipation capacity and reliability.

[0068] In addition, the above-mentioned FA prefabricated parts can be processed into 2D-FA prefabricated parts and 3D-FA prefabricated parts, which are compatible with multi-channel ELS optical modules, with strong adaptability and high scalability. Attached Figure Description

[0069] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0070] Figure 1 This is a flowchart of a method for fabricating an ELS optical module provided in an embodiment of this application. Detailed Implementation

[0071] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0072] See Figure 1 , Figure 1 This is a flowchart illustrating a method for fabricating an ELS optical module according to an embodiment of this application, as shown below. Figure 1 As shown, the method includes the following steps:

[0073] Step 101: Select FA substrate, optical fiber, adhesive material and auxiliary materials, wherein the auxiliary materials include cover plate, thermally conductive substrate and laser array.

[0074] Step 102: Using the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials, a FA preform is obtained.

[0075] Step 103: Fix the thermally conductive substrate to the inner wall of the ELS housing, and fix the laser array to the surface of the thermally conductive substrate.

[0076] Step 104: Align the FA preform with the laser array and fix the FA preform in the bonding area of ​​the thermally conductive substrate.

[0077] Step 105: Secure the optical fiber on the FA preform and lead the optical fiber out from the ELS housing.

[0078] Step 106: Install the TEC temperature control chip, drive circuit, and heat dissipation components.

[0079] Step 107: Seal the ELS housing completely and perform performance testing to prepare the ELS optical module.

[0080] In this embodiment, a high-precision silicon-based V-groove substrate is selected. Optionally, the FA substrate size is 6mm × 3mm × 1.0mm, the silicon substrate purity is greater than or equal to 99.99%, and the coefficient of thermal expansion is [missing value]. The surface flatness is less than or equal to 0.1μm to avoid gaps in subsequent bonding.

[0081] Polarization-maintaining fiber with a core diameter of 9μm and a cladding diameter of 125μm was selected. The surface coating was removed, and the cladding was retained. A fiber length of 150mm was reserved for subsequent straightening and lead-out.

[0082] Low-stress UV-curable adhesive is selected, with a viscosity of [missing value]. After curing, the coefficient of thermal expansion is less than or equal to It can withstand high temperatures of ≥120℃ to avoid stress caused by curing, which could lead to fiber optic misalignment.

[0083] The cover plate is optional, and can be made of silicon with dimensions consistent with the silicon-based V-groove substrate.

[0084] A thermally conductive substrate is selected, optionally with dimensions of 20mm × 10mm × 0.8mm, and a thermal conductivity greater than or equal to [missing value]. It should be understood that the above-mentioned thermally conductive substrate is also called an aluminum nitride (AlN) substrate.

[0085] A laser array is selected, optionally arranged in a 16-channel, 2×8 matrix configuration with a 250μm aperture spacing, matching the multidimensional FA channel spacing.

[0086] Prepare the processing tools, including a deep silicon etching machine, fiber optic stripper, vacuum adsorption fiber threading machine, UV curing lamp (optional, UV curing lamp wavelength is 365nm, power is 100W), end face grinding machine, and antireflection coating machine.

[0087] Prepare alignment and testing tools, including a visual alignment system, an optical power meter, a return loss tester, and a microscope.

[0088] Prepare cleaning tools, including lint-free cloths, anhydrous ethanol, and a nitrogen spray gun, to avoid dust affecting the bonding and coupling accuracy.

[0089] Furthermore, FA preforms are fabricated using FA substrate, optical fiber, adhesive material, and auxiliary materials. These FA preforms include... Precast components and Precast components.

[0090] Furthermore, the thermally conductive substrate is fixed to the inner wall of the ELS housing, and the laser array is fixed to the surface of the thermally conductive substrate. The FA preform is aligned with the laser array, and the FA preform is fixed to the bonding area of ​​the thermally conductive substrate. For specific implementation details, please refer to subsequent embodiments.

[0091] In this embodiment, after fixing the FA preform to the bonding area of ​​the thermally conductive substrate, the optical fiber on the FA preform is fixed, and the optical fiber is led out from the ELS housing. Specifically:

[0092] The polarization-maintaining fibers leading out from the rear end of the FA preform are combed. Optionally, the number of fibers is 16. After combing, the bending radius is controlled to be greater than or equal to 15mm to avoid stress caused by an excessively small bending radius, which would lead to increased fiber loss.

[0093] An integrated metal cable clamp is used, optionally with dimensions of 10mm × 2mm × 0.5mm. The combed optical fiber is fixed inside the clamp, which is then secured to the ELS housing with screws. The fixing torque is [not specified]. Ensure the optical fiber is secure and without displacement. After securing the optical fiber, lead it out through the pre-drilled fiber optic exit hole in the ELS housing. Install a sealing sleeve at the exit hole to prevent dust and moisture from entering the module and to avoid damage caused by friction between the optical fiber and the exit hole.

[0094] Subsequently, the TEC temperature control chip, drive circuit, and heat dissipation components are installed. The ELS casing is then completely sealed, and performance testing is conducted. The finished product that passes the performance test is identified as the manufactured ELS optical module.

[0095] In this embodiment, a single multi-dimensional fiber array is used to replace multiple sets of MT ferrules to achieve miniaturization of the space occupied; alignment of the FA preform with the laser array is achieved, reducing optical path loss and improving channel consistency; FA substrate with a thermal expansion coefficient matching that of the laser array and the thermally conductive substrate is selected to improve thermal stability; the assembly process is simplified and mass production costs are reduced by using FA preform alignment and ELS optical module curing process; the FA substrate is bonded to the thermally conductive substrate, the thermally conductive substrate integrates heat insulation trenches, and the optical fiber is neatly led out, thereby improving heat dissipation capacity and reliability.

[0096] Optionally, the process of obtaining an FA preform by applying the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials includes:

[0097] V-grooves are etched on the FA substrate;

[0098] The optical fiber is fixed within the V-groove of the FA substrate;

[0099] The cover plate is pressed onto the FA substrate to prepare the following: Precast components;

[0100] Regarding the The prefabricated parts undergo end face treatment and coating.

[0101] In this embodiment, the FA substrate is placed in a cleanroom, its surface is wiped with anhydrous ethanol, and dried with a nitrogen spray gun to remove surface dust and oil. The FA substrate is then placed in a deep silicon etching machine, and V-grooves are etched according to a 2×8 matrix specification. Optionally, the V-groove depth is 62.5 μm, the V-groove angle is 90°, the channel spacing is 250 μm, and the etching accuracy is controlled within ±0.5 μm to ensure the precise position of each V-groove. After etching, the FA substrate is removed and placed in an annealing furnace, where it is annealed at 800°C for 30 minutes to eliminate substrate stress generated during etching and prevent subsequent deformation.

[0102] The surface coating of the polarization-maintaining fiber is stripped using fiber strippers, optionally with a stripping length of 10 mm. During stripping, damage to the fiber cladding and core should be avoided. After stripping, the fiber is inspected under a microscope to confirm the absence of scratches and breakage. The stripped fibers are then held in place using a vacuum fiber insertion machine, and 16 fibers are sequentially embedded into the corresponding V-grooves of a silicon-based V-groove substrate. The embedding depth of each fiber is consistent with the V-groove depth, and the fiber core is aligned with the center of the V-groove with a deviation of less than or equal to 0.1 μm. A low-stress UV-curable adhesive is evenly applied to the contact area between the V-groove and the fiber using a micro-dispensing machine. The adhesive layer thickness is controlled at 5-10 μm to avoid fiber misalignment due to excessive thickness and to prevent adhesive overflow from contaminating the fiber end face. The substrate with adhesive is placed under a UV curing lamp, 5 cm away from the light source, and cured at a constant temperature (25℃) for 60 seconds at a wavelength of 365 nm and a power of 100 W to ensure complete curing. After curing, the fiber is inspected under a microscope to confirm the absence of fiber misalignment and air bubbles in the adhesive layer.

[0103] Clean the silicon cover plate with anhydrous ethanol and dry it with nitrogen. Align it and place it over the silicon-based V-groove substrate, ensuring a seamless fit between the cover plate and the substrate with a deviation of less than or equal to 0.1 mm. Apply a small amount of UV-curable adhesive to the edge of the cover plate, then place it under a UV curing lamp for 30 seconds to complete the cover plate fixation and form a complete 2D-FA preform.

[0104] The 2D-FA preform is placed in an end-face polishing machine and polished using an 8° APC bevel angle at a speed of 500 r / min for 3 minutes, ensuring an end-face roughness of less than or equal to 0.01 μm to prevent end-face reflection. The polished preform is then placed in an anti-reflection coating machine to coat the fiber end face with a double-layer AR anti-reflection coating of 130-140 nm thickness, ensuring a reflectivity of less than or equal to 0.1% and a return loss of greater than or equal to 60 dB. After coating, the return loss of each channel is tested using a return loss tester. Preforms that fail the test (e.g., return loss less than 60 dB) are re-polished and re-coated.

[0105] Observation under a microscope The fiber optic cable arrangement of the prefabricated components was confirmed to be free from misalignment and damage. The optical power meter was used to conduct a preliminary test on the optical fiber transmittance to ensure that there were no broken fibers or serious losses in each channel.

[0106] In this embodiment, the positional accuracy of each channel is ensured by the integrated matrix V-groove process, the optical power deviation between channels is controlled within 0.1dB, and the return loss is stably reached above 60dB, which meets the requirements of high-power ELS optical signal transmission and solves the problems of high loss and poor consistency in traditional solutions.

[0107] Optionally, aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate includes:

[0108] Clean the 2D-FA preform;

[0109] The 2D-FA preform is placed in the bonding area of ​​the thermally conductive substrate;

[0110] Adjust the 2D-FA preform so that each fiber core of the 2D-FA preform is aligned with the light-emitting port of the corresponding laser array;

[0111] Apply curing adhesive to the edges of the 2D-FA preform;

[0112] A curing adhesive is applied to the bonding area between the 2D-FA preform and the thermally conductive substrate, and then cured at a constant temperature using a UV curing lamp.

[0113] In this embodiment, the finished 2D-FA preform is wiped with anhydrous ethanol on the end face and bottom face, and then dried with a nitrogen spray gun to ensure that there is no dust or adhesive residue.

[0114] The 2D-FA preform is placed in the bonding area of ​​the thermally conductive substrate. The horizontal and vertical positions and angles of the 2D-FA preform are adjusted by a vision alignment system to ensure that each fiber core is precisely aligned with the corresponding laser emission port. During the alignment process, the coupling efficiency is detected in real time by an optical power meter to ensure that the coupling efficiency of each channel is greater than or equal to 85% and the power deviation between channels is less than or equal to 0.1dB.

[0115] After alignment, use a micro-dispensing machine to apply UV-curable adhesive to the edge of the 2D-FA preform, ensuring it does not obstruct the light path, for temporary fixation to prevent displacement during subsequent operations.

[0116] After confirming that the alignment accuracy and coupling efficiency meet the standards by using a vision alignment system and an optical power meter, a low-stress UV-curable adhesive is uniformly coated on the bonding surface of the 2D-FA preform and the AlN substrate. Optionally, the adhesive layer thickness is 5-8μm. The substrate is then placed in a UV curing lamp and cured at a wavelength of 365nm and a power of 100W for 90 seconds to ensure a firm and gapless bond.

[0117] After curing, the bonding was observed again under a microscope to confirm that there was no misalignment or air bubbles. The insertion loss of each channel was tested with an optical power meter to ensure that the insertion loss was less than or equal to 0.5dB and the return loss was greater than or equal to 60dB.

[0118] In this embodiment, a process of one-time overall alignment and one-time curing of FA prefabricated parts is adopted to reduce assembly steps and assembly time; at the same time, the amount of materials such as MT pins and connectors is reduced, thereby reducing costs and making it suitable for mass production.

[0119] Optionally, the process of obtaining an FA preform by applying the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials includes:

[0120] V-grooves are etched on the FA substrate;

[0121] The optical fiber is fixed within the V-groove of the FA substrate;

[0122] The cover plate is pressed onto the FA substrate to prepare two 2D-FA preforms.

[0123] Preparation of silicon separator;

[0124] The two 2D-FA preforms are stacked through the silicon separator to prepare a 3D-FA preform.

[0125] Two 2D-FA preforms were prepared according to the method for preparing 2D-FA preforms in the above embodiments.

[0126] The silicon separator is fabricated by selecting a silicon material separator with the same dimensions as the 2D-FA preform and a thickness of 0.2 mm. Fiber clearance grooves are etched on the surface to avoid interference between the upper and lower fiber layers.

[0127] Two 2D-FA prefabricated pieces were stacked using a silicon separator, with the upper and lower fiber channels corresponding one-to-one. During stacking, the positions were adjusted using a vision alignment system with an alignment accuracy of less than or equal to 0.1 μm. Then, a low-stress UV-curable adhesive was used to fix the three layers (upper FA layer + silicon separator + lower FA layer) into a single unit. The curing conditions were the same as those in the above embodiment.

[0128] On the 3D-FA preform, channel-separating thermal trenches are etched using a deep silicon etching machine. The trenches are 0.5 mm wide and 0.3 mm deep, located between every two channels, to isolate the heat sources of each channel and suppress thermal crosstalk.

[0129] Following the testing method for 2D-FA preforms in the above embodiments, the return loss and light transmittance of 3D-FA are tested.

[0130] Optionally, aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate includes:

[0131] Clean the 3D-FA preform;

[0132] The 3D-FA preform is placed in the bonding area of ​​the thermally conductive substrate;

[0133] Adjust the 3D-FA preform so that each fiber core of the 3D-FA preform is aligned with the light-emitting port of the corresponding laser array;

[0134] Apply curing adhesive to the edges of the 3D-FA preform;

[0135] A curing adhesive is applied to the bonding area between the 3D-FA preform and the thermally conductive substrate, and then cured at a constant temperature using a UV curing lamp.

[0136] In this embodiment, a 32-channel laser array is selected and fixed on an AlN substrate.

[0137] The 3D-FA preform is placed in the bonding area of ​​the AlN substrate. Using a vision alignment system, the position of the 3D-FA is adjusted so that the upper and lower fiber cores are aligned with their corresponding laser emission ports. The alignment accuracy is less than or equal to 0.1 μm. The coupling efficiency is monitored in real time using an optical power meter. Subsequent fixing and testing steps are consistent with the processing method for the 2D-FA preform in the above embodiment, ensuring that the insertion loss of each channel is less than or equal to 0.6 dB and the temperature difference between channels is less than or equal to 1 °C.

[0138] Optionally, before aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate, the method further includes:

[0139] Select a microlens array;

[0140] Clean the microlens array;

[0141] The microlens array is placed between the laser array and the bonding area of ​​the thermally conductive substrate;

[0142] Adjust the position of the microlens array so that it is aligned with the light-emitting port of the corresponding laser array and the optical fiber channel;

[0143] The microlens array is fixed on the thermally conductive substrate;

[0144] Aligning the FA preform with the laser array includes:

[0145] The position of the FA preform is adjusted so that each fiber core of the FA preform is aligned with the light-emitting port of the corresponding laser array through the microlens array.

[0146] In this embodiment, a silicon-based microlens array is selected, with dimensions identical to the 2D-FA preform, arranged in a 2×8 matrix. Each microlens corresponds to a laser emission port and a fiber optic channel, with a focal length of 1.5 mm and an aperture of 50 μm. The two ends of the microlens array are wiped with anhydrous ethanol and dried with a nitrogen spray gun to ensure no dust or stains. The microlens array is placed between the laser array and the 2D-FA bonding area. Using a vision alignment system, the position of the microlens array is adjusted to ensure that each microlens is precisely aligned with its corresponding laser emission port and fiber optic channel, with an alignment accuracy of less than or equal to 0.1 μm. The microlens array is fixed to the AlN substrate using low-stress UV-curable adhesive, with curing conditions consistent with those in the previous embodiment. After curing, the alignment accuracy is checked to ensure no misalignment.

[0147] The steps for aligning the FA preform with the laser array include:

[0148] Adjust the position of the 2D-FA preform so that each fiber core is precisely aligned with the corresponding laser emission port through the microlens array. During the alignment process, use an optical power meter to detect the coupling efficiency in real time to ensure that the coupling efficiency of each fiber is greater than or equal to 88%. Subsequent fixing and testing steps are the same as in the above embodiment.

[0149] Optionally, fixing the thermally conductive substrate to the inner wall of the ELS housing includes:

[0150] Clean the thermally conductive substrate;

[0151] A mating area matching the FA preform is etched on the surface of the thermally conductive substrate;

[0152] Thermal grease is applied to the back side of the bonding area of ​​the thermally conductive substrate;

[0153] The thermally conductive substrate is fixed to the inner wall of the ELS housing.

[0154] In this embodiment, the thermally conductive substrate is placed in a cleanroom, its surface is wiped with anhydrous ethanol, and dried with a nitrogen spray gun to remove surface dust, oil, and impurities, thus avoiding gaps during bonding that could affect heat conduction.

[0155] A bonding area matching the shape of the FA preform is etched on the AlN substrate using a laser etching machine. Optionally, the bonding area is 6mm×3mm in size, and the surface of the bonding area is flattened with a flatness of less than or equal to 0.1μm to ensure that there are no gaps after the FA preform is bonded.

[0156] A layer of thermal grease is applied to the back side of the AlN substrate bonding area. Optionally, the thermal conductivity of the thermal grease is greater than or equal to that of the substrate. The coating thickness is 10-15μm, applied evenly without bubbles or gaps, and is used for subsequent thermal conduction docking with the ELS shell.

[0157] The pretreated AlN substrate is placed inside the ELS metal casing and secured with screws. Optionally, the screws are M1.0 with a torque of [missing value]. After fixing, the substrate surface is not tilted and the deviation is less than or equal to 0.1 mm, thus completing the AlN substrate pretreatment.

[0158] Optionally, fixing the laser array to the surface of the thermally conductive substrate includes:

[0159] Clean the laser array;

[0160] The laser array is fixed on the surface of the thermally conductive substrate;

[0161] Adjust the laser array so that the emission port of the laser array corresponds to the optical fiber channel of the FA preform.

[0162] In this embodiment, a lint-free cloth soaked in anhydrous ethanol is used to gently wipe the light-emitting end face of the laser array to remove surface dust and stains, thus avoiding affecting the emission of optical signals.

[0163] The 16-channel laser array is fixed on the left side of the AlN substrate, aligned with the bonding area of ​​the FA preform, with the laser emission port facing the bonding area of ​​the FA preform. The fixing method is AuSn eutectic bonding, where the eutectic temperature is 300℃ and the holding time is 10 minutes to ensure that the laser is firmly fixed and without loosening.

[0164] The position of the laser array is adjusted using a vision alignment system to ensure that the 16 emission ports of the laser correspond one-to-one with the 16 fiber optic channels of the FA preform, with an alignment accuracy of less than or equal to 0.1 μm. The alignment position parameters are recorded for subsequent alignment reference of the FA preform.

[0165] Optionally, the mounting of the TEC temperature control chip, drive circuit, and heat dissipation assembly includes:

[0166] The TEC temperature control chip is installed between the laser array and the FA preform, with the cold end of the TEC temperature control chip attached to the back of the laser array and the hot end of the TEC temperature control chip attached to the thermally conductive substrate.

[0167] The driving circuit is fixed to the inner wall of the ELS housing, and the driving circuit, the laser array, and the TEC temperature control chip are connected by gold wire bonding.

[0168] One end of the heat dissipation component is attached to the thermally conductive substrate, and the other end of the heat dissipation component is attached to the inner wall of the ELS housing;

[0169] Connect the pins of the TEC temperature control chip, the drive circuit, and the ELS optical module.

[0170] In this embodiment, a TEC temperature control chip, optionally with dimensions of 5mm × 5mm × 0.4mm, is fixed on an AlN substrate in the empty area between the laser array and the FA preform. The cold end of the TEC temperature control chip is attached to the back of the laser array, and the hot end is attached to the AlN substrate. Thermal conductive gel is used, optionally with a thermal conductivity greater than or equal to... Fill the gaps to ensure smooth heat conduction.

[0171] In this embodiment, the driving circuit is fixed in the empty area inside the ELS housing. Optionally, the size of the driving circuit is 8mm×8mm×0.8mm. The driving circuit is connected to the laser array and the TEC temperature control chip by gold wire bonding with a wire diameter of 25μm and a bonding accuracy of ±0.5μm to ensure reliable electrical connection.

[0172] In this embodiment, the heat dissipation component has dimensions of 20mm × 10mm × 0.1mm and a thermal conductivity greater than or equal to 10mm. A graphite heat sink is attached to the thermal grease on the back of the AlN substrate, with the other end of the graphite heat sink attached to the inner wall of the ELS metal casing, forming a complete heat dissipation path of "laser → TEC chip → AlN substrate → graphite heat sink → casing".

[0173] In this embodiment, the pins of the TEC temperature control chip, the drive circuit, and the ELS optical module are wired together. During the wiring process, wire crossing and short circuits are avoided. After the wiring is completed, the wires are fixed with insulating glue to prevent vibration from causing the wires to fall off.

[0174] Optionally, the process of sealing the ELS housing and performing performance testing includes:

[0175] Apply sealant to the seams of the ELS housing and fasten the housing cover.

[0176] Optical performance testing, thermal performance testing, and reliability testing are performed on the ELS optical module.

[0177] The optical performance tests include insertion loss testing, return loss testing, and power flatness testing, while the reliability tests include vibration testing and insertion / removal testing.

[0178] In this embodiment, a high-temperature resistant sealant is applied to the seams of the ELS housing. Optionally, the high-temperature sealant has a temperature resistance of ≥120℃ and a waterproof rating of IP67. The sealant is applied evenly without bubbles or gaps. Then, the housing cover is snapped on and fixed with screws. Optionally, the torque is 0.8 N·m, thus completing the sealing of the entire machine and preventing dust and moisture from entering.

[0179] Optical performance testing, thermal performance testing, and reliability testing are performed on the ELS optical module. The optical performance testing includes insertion loss testing, return loss testing, and power flatness testing. The reliability testing includes vibration testing and insertion / removal testing.

[0180] The above insertion loss test is implemented as follows: use an optical power meter to detect the insertion loss of each channel to ensure that the insertion loss is less than or equal to 0.5dB and the channel deviation is less than or equal to 0.1dB.

[0181] The above-mentioned return loss test is implemented as follows: use a return loss tester to test the return loss of each channel to ensure that it is greater than or equal to 60dB.

[0182] The above power flatness test is implemented by detecting the output power of each channel and ensuring that the power flatness deviation is less than or equal to 1.8%.

[0183] The above-mentioned thermal performance test is implemented as follows: the ELS optical module is placed in a high and low temperature test chamber, and... Within a wide temperature range of -85℃, it runs continuously for 24 hours to detect the internal temperature and insertion loss fluctuation of the ELS optical module, ensuring that the temperature is controlled at 25±0.5℃ and the insertion loss fluctuation is less than or equal to 0.05dB.

[0184] The above vibration test was conducted by performing a 1500g impact and a 10-2000Hz vibration test. After the test, the module was undamaged, the optical fiber was not loose, and the optical performance met the standards.

[0185] The above-mentioned hot-plug test was conducted by performing 1000 hot-plug tests. After the test, the optical performance of the ELS optical module did not change significantly, and the optical fiber was not damaged.

[0186] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0187] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0188] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for fabricating an ELS optical module, characterized in that, The method includes: FA substrate, optical fiber, adhesive material and auxiliary materials are selected, wherein the auxiliary materials include cover plate, thermally conductive substrate and laser array; FA preforms are obtained by using the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials. The thermally conductive substrate is fixed to the inner wall of the ELS housing, and the laser array is fixed to the surface of the thermally conductive substrate; Align the FA preform with the laser array and fix the FA preform in the bonding area of ​​the thermally conductive substrate; Secure the optical fiber on the FA preform and lead the optical fiber out from the ELS housing; Install the TEC temperature control chip, drive circuit, and heat dissipation components; The ELS housing is sealed as a whole, and performance tests are performed to prepare the ELS optical module. The process of using the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials to obtain an FA preform includes: V-grooves are etched on the FA substrate; The optical fiber is fixed within the V-groove of the FA substrate; The cover plate is pressed onto the FA substrate to prepare a 2D-FA preform; The 2D-FA preform undergoes end face treatment and coating. The step of aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate includes: Clean the 2D-FA preform; The 2D-FA preform is placed in the bonding area of ​​the thermally conductive substrate; Adjust the 2D-FA preform so that each fiber core of the 2D-FA preform is aligned with the light-emitting port of the corresponding laser array; Apply curing adhesive to the edges of the 2D-FA preform; A curing adhesive is applied to the bonding area between the 2D-FA preform and the thermally conductive substrate, and a UV curing lamp is used for constant temperature curing. The step of fixing the thermally conductive substrate to the inner wall of the ELS housing includes: Clean the thermally conductive substrate; A mating area matching the FA preform is etched on the surface of the thermally conductive substrate; Thermal grease is applied to the back side of the bonding area of ​​the thermally conductive substrate; The thermally conductive substrate is fixed to the inner wall of the ELS housing; The installation of the TEC temperature control chip, drive circuit, and heat dissipation assembly includes: The TEC temperature control chip is installed between the laser array and the FA preform, with the cold end of the TEC temperature control chip attached to the back of the laser array and the hot end of the TEC temperature control chip attached to the thermally conductive substrate. The driving circuit is fixed to the inner wall of the ELS housing, and the driving circuit, the laser array, and the TEC temperature control chip are connected by gold wire bonding. One end of the heat dissipation component is attached to the thermally conductive substrate, and the other end of the heat dissipation component is attached to the inner wall of the ELS housing; Connect the pins of the TEC temperature control chip, the drive circuit, and the ELS optical module.

2. The method according to claim 1, characterized in that, The process of using the FA substrate, the optical fiber, the adhesive material, and the auxiliary materials to obtain an FA preform includes: V-grooves are etched on the FA substrate; The optical fiber is fixed within the V-groove of the FA substrate; The cover plate is pressed onto the FA substrate to prepare two 2D-FA preforms. Preparation of silicon separator; The two 2D-FA preforms are stacked through the silicon separator to prepare a 3D-FA preform.

3. The method according to claim 2, characterized in that, The step of aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate includes: Clean the 3D-FA preform; The 3D-FA preform is placed in the bonding area of ​​the thermally conductive substrate; Adjust the 3D-FA preform so that each fiber core of the 3D-FA preform is aligned with the light-emitting port of the corresponding laser array; Apply curing adhesive to the edges of the 3D-FA preform; A curing adhesive is applied to the bonding area between the 3D-FA preform and the thermally conductive substrate, and then cured at a constant temperature using a UV curing lamp.

4. The method according to claim 1, characterized in that, Before aligning the FA preform with the laser array and fixing the FA preform to the bonding area of ​​the thermally conductive substrate, the method further includes: Select a microlens array; Clean the microlens array; The microlens array is placed between the laser array and the bonding area of ​​the thermally conductive substrate; Adjust the position of the microlens array so that it is aligned with the light-emitting port of the corresponding laser array and the optical fiber channel; The microlens array is fixed on the thermally conductive substrate; Aligning the FA preform with the laser array includes: The position of the FA preform is adjusted so that each fiber core of the FA preform is aligned with the light-emitting port of the corresponding laser array through the microlens array.

5. The method according to claim 1, characterized in that, The step of fixing the laser array to the surface of the thermally conductive substrate includes: Clean the laser array; The laser array is fixed on the surface of the thermally conductive substrate; Adjust the laser array so that the emission port of the laser array corresponds to the optical fiber channel of the FA preform.

6. The method according to claim 1, characterized in that, The process of sealing the ELS housing and performing performance testing includes: Apply sealant to the seams of the ELS housing and fasten the housing cover. Optical performance testing, thermal performance testing, and reliability testing are performed on the ELS optical module. The optical performance tests include insertion loss testing, return loss testing, and power flatness testing, while the reliability tests include vibration testing and insertion / removal testing.

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