Fixing block and optical module

Abstract

The application discloses a fixing block and an optical module, wherein the optical module comprises a circuit board, a photon chip, a laser device and a transmitting optical fiber; the fixing block comprises a bearing part embedded in the circuit board and a mounting part attached to the circuit board; the mounting part is connected with the bearing part and forms a receiving cavity together with the bearing part; the receiving cavity comprises a first cavity and a second cavity which are connected in communication; the fixing block has a first opening connected with the first cavity and the second cavity and a second opening connected with the first cavity; the laser device is located in the second cavity and is mounted on the bearing part; one end of the transmitting optical fiber is located in the first cavity and is mounted on the bearing part; and the photon chip is mounted on the circuit board and is at least partially located in the first opening. Through the structural design of the fixing block on the circuit board, the photon chip and the surrounding circuit board are supported and fixed, and the problem that the optical coupling between the photon chip and the laser device and the transmitting optical fiber is deteriorated due to the local deformation of the circuit board is avoided.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic technology, specifically relating to a fixed block and an optical module. Background Technology

[0002] Traditional high-speed optical modules typically have transmission rates of 400G-1.6T. A standard switch can accommodate a maximum of 32-48 800G QSFP-DD ports, requiring a large number of optical modules and significantly increasing system complexity and power consumption. In contrast, a single high-density pluggable optical module (eXtra-dense Pluggable Optics, XPO) can replace eight 800G optical modules, greatly improving bandwidth density per unit space. This allows for a simpler switch port panel design, and the reduced number of optical modules significantly lowers power consumption. XPO optical modules are becoming the mainstream design trend.

[0003] Currently, there are two main technical approaches to increasing the bandwidth density of optical modules: one is to increase the transmission rate of a single channel, and the other is to increase the number of channels. For silicon optical modules, the electro-optic effect of silicon material is very weak. The mainstream technology for silicon-based modulators is based on carrier dispersion. Methods to improve modulation efficiency include increasing the doping concentration and lengthening the modulator, but these increase optical loss and reduce modulation bandwidth, which poses a fundamental limitation. Therefore, the mainstream approach to increasing the transmission rate of silicon optical modules is only to increase the number of channels.

[0004] However, the limited space on the circuit board of optical modules, coupled with high device integration and a direct increase in the number of channels, places higher demands on heat dissipation and signal transmission. In conventional optical modules, photonic chips are flip-chip soldered onto the circuit board to achieve better signal integrity and heat dissipation. However, due to issues such as thermal expansion coefficient mismatch between the photonic chip and the circuit board, as well as deformation of the circuit board caused by external stress, optical coupling misalignment between the photonic chip and other devices can occur, resulting in abnormal light output.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a fixing block and an optical module that can improve the coupling strength between optical devices in the optical module.

[0007] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution:

[0008] A fixing block is applied to an optical module, the optical module including a circuit board, a photonic chip, a laser device, and a transmitting optical fiber. The fixing block includes a carrier portion embedded in the circuit board and a mounting portion mounted on the circuit board. The mounting portion is connected to the carrier portion and forms a receiving cavity with the carrier portion. The receiving cavity includes a first cavity and a second cavity that are connected to each other. The fixing block has a first opening that is connected to the first cavity and the second cavity and a second opening that is connected to the first cavity. The laser device is located in the second cavity and mounted on the carrier portion. One end of the transmitting optical fiber is located in the first cavity and mounted on the carrier portion, and the transmitting optical fiber passes through the second opening. The photonic chip is mounted on the circuit board and is at least partially located in the first opening.

[0009] In one or more embodiments of the present invention, the first cavity and the second cavity are distributed along a first direction, the first opening is connected to the first cavity and the second cavity along a second direction, the second opening is connected to the first cavity along a second direction, and the first direction and the second direction intersect.

[0010] In one or more embodiments of the present invention, the mounting portion includes an extension extending to the outside of the carrier portion, the extension being recessed to form a first opening on the side facing the circuit board.

[0011] In one or more embodiments of the present invention, the support portion located in the second cavity is provided with a third opening on the side away from the first opening, the circuit board portion is located in the third opening, and the laser device is electrically connected to the circuit board in the third opening.

[0012] In one or more embodiments of the present invention, the mounting portion has a mounting area on one side surface facing the circuit board, the projection area of ​​the mounting area on the circuit board is located outside the projection area of ​​the carrier portion on the circuit board, and at least a portion of the mounting area is provided with an adhesive layer between it and the circuit board.

[0013] In one or more embodiments of the present invention, the mounting area includes a first region that is bonded to the circuit board and a second region that is recessed relative to the first region, wherein the adhesive layer is located at least in the second region.

[0014] In one or more embodiments of the present invention, the first region and the second region are provided in multiple intervals, and the first region and the second region extend in the same direction.

[0015] In one or more embodiments of the present invention, the recess depth of the second region relative to the first region is 0.05 mm to 0.2 mm.

[0016] In one or more embodiments of the present invention, the support portion below the second cavity is recessed relative to the support portion below the first cavity.

[0017] In one or more embodiments of the present invention, the fixing block is a metal fixing block or a ceramic fixing block; and / or,

[0018] The minimum thickness of the fixing block in the direction perpendicular to the circuit board is greater than or equal to 0.9 mm.

[0019] A specific embodiment of the present invention also provides an optical module, including a circuit board, a photonic chip, a laser device, a transmitting optical fiber, and the aforementioned fixing block. The photonic chip and the laser device are electrically connected to the circuit board, and the laser device and the transmitting optical fiber are optically coupled to the photonic chip.

[0020] In one or more embodiments of the present invention, a heat-conducting layer is provided between the mounting portion and the photonic chip within the first opening.

[0021] In one or more embodiments of the present invention, a first substrate is provided on the surface of the carrier portion within the first cavity, and the transmitting optical fiber is mounted on the first substrate; and / or,

[0022] The second substrate is provided on the surface of the support portion inside the second cavity, and the laser device is mounted on the second substrate.

[0023] In one or more embodiments of the present invention, the first substrate and / or the second substrate are ceramic substrates; and / or,

[0024] The thickness of the first substrate and / or the second substrate is 0.1 mm to 0.5 mm; and / or,

[0025] The thermal conductivity of the first substrate and / or the second substrate is greater than or equal to 200 W / m·K.

[0026] Compared with the prior art, the fixing block and optical module of the present invention, through the structural design of the fixing block on the circuit board, realize the support and fixation of the photonic chip and the surrounding circuit board, which greatly improves the bending stiffness of the local area of ​​the photonic chip, effectively reduces the bending moment transmitted from the peripheral circuit board, avoids the problem of optical coupling between the photonic chip and the laser device and the transmitting optical fiber being degraded due to local deformation of the circuit board, and ensures that its coupling efficiency remains at the optimal level under different environments.

[0027] Meanwhile, the fixing block can also provide additional heat dissipation paths for photonic chips, laser devices, etc., thereby improving the overall heat dissipation capacity. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, 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 recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a top view of the optical module in one embodiment of the present invention.

[0030] Figure 2 This is an exploded top view of an optical module in one embodiment of the present invention.

[0031] Figure 3 This is a partially enlarged view of the optical module in one embodiment of the present invention.

[0032] Figure 4 This is a top view of the fixing block in one embodiment of the present invention.

[0033] Figure 5 This is a bottom view of the fixing block in one embodiment of the present invention.

[0034] Figure 6 This is another enlarged view of the optical module in one embodiment of the present invention.

[0035] Figure 7 This is a partially enlarged view of the optical module in another embodiment of the present invention.

[0036] Figure 8 This is a bottom view of the optical module in one embodiment of the present invention.

[0037] Figure 9 This is a partially enlarged view of the optical receiving component in one embodiment of the present invention. Detailed Implementation

[0038] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0039] The terms "coupled," "connected," or "linked" in the specification include both direct and indirect connections. An indirect connection is a connection made through an intermediate medium, such as an electrical conduction medium, which may have parasitic inductance or capacitance. Indirect connections may also include connections made through other active or passive devices to achieve the same or similar functional purpose, such as connections through switches, follower circuits, or other circuits or components. Furthermore, in the invention, terms such as "first" and "second" are primarily used to distinguish one technical feature from another, and do not necessarily require or imply any actual relationship, quantity, or order between these technical features.

[0040] In the detailed description of this specification, reference is made to the accompanying drawings, which form a part thereof, wherein like reference numerals always denote like parts, and wherein exemplary embodiments are shown by way of example that may be implemented. It should be understood that other embodiments may be utilized, and structural or logical changes may be made, without departing from the scope of the invention. Therefore, the following detailed description should not be considered limiting.

[0041] For the purposes of this invention, the phrase "A and / or B" refers to (A), (B), or (A and B). For the purposes of this invention, the phrase "A, B and / or C" refers to (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).

[0042] Various components and devices may be mentioned or shown in the singular form herein, but only for the convenience of discussion, and any element mentioned in the singular form may include multiple such elements as taught herein.

[0043] The description uses the phrases "in one embodiment," "in other embodiments," or "in some embodiments," each of which can refer to one or more of the same or different embodiments. Furthermore, the terms "comprising," "including," "having," etc., used in relation to embodiments of the invention are synonymous.

[0044] Combination Figures 1-5 As shown, the present invention provides an optical module, which includes a circuit board 10, a photonic chip 20, a laser device 31, a transmitting optical fiber 41, and a fixing block 50.

[0045] The fixing block 50 includes a support portion 52 embedded in the circuit board 10 and a mounting portion 51 mounted on the circuit board 10. The mounting portion 51 is connected to the support portion 52 and forms a receiving cavity with the support portion 52. The receiving cavity includes a first cavity 53 and a second cavity 54 that are connected to each other. The fixing block 50 has a first opening 55 that is connected to the first cavity 53 and the second cavity 54, and a second opening 56 that is connected to the first cavity 53. The laser device 31 is located in the second cavity 54 and mounted on the support portion 52. One end of the transmitting optical fiber 41 is located in the first cavity 53 and mounted on the support portion 52. The transmitting optical fiber 41 passes through the second opening 56. The photonic chip 20 is mounted on the circuit board 10 and is at least partially located in the first opening 55.

[0046] The photonic chip 20 can be coupled and connected to the laser device 31 and the transmitting optical fiber 41 in the housing cavity through the first opening 55, thereby realizing the function of modulating the laser emitted by the laser device 31 and then outputting the modulated light to the outside through the transmitting optical fiber 41.

[0047] In conventional silicon photonics modules, photonic chips are flip-chip soldered onto circuit boards to achieve better signal integrity and heat dissipation. However, due to issues such as thermal expansion coefficient mismatch between these photonic chips and circuit boards, as well as deformation of the circuit boards caused by external stress, optical coupling misalignment between the photonic chips and various devices can occur. Even micron-level deformation misalignment can lead to severe degradation of optical path coupling efficiency and cause abnormal light output.

[0048] The optical module of the present invention, through the mounting part 51 and the circuit board 10, plays a supporting and fixing role for the photonic chip 20 and the surrounding area of ​​the circuit board 10, which greatly improves the bending stiffness of the local area of ​​the photonic chip 20, effectively reduces the bending moment transmitted from the peripheral circuit board 10, and avoids the problem of deterioration of the optical coupling between the photonic chip 20 and the laser device 31 and the transmitting optical fiber 41 due to local deformation of the circuit board 10, thus ensuring that its coupling efficiency remains at the optimal level under different environments.

[0049] Preferably, the photonic chip 20 is flip-chip bonded to the circuit board 10. In traditional wire bonding, long gold wires introduce huge parasitic inductance and capacitance, resulting in severe signal distortion and bandwidth limitation; wire bonding requires space for the gold ball curvature and pads, reducing space utilization; long heat dissipation paths also lead to reduced heat dissipation efficiency; flip-chip bonding has significant advantages in signal transmission path, thermal management, and integration design flexibility.

[0050] In one embodiment, the first cavity 53 and the second cavity 54 are distributed along a first direction, the first opening 55 is connected to the first cavity 53 and the second cavity 54 along a second direction, and the second opening 56 is connected to the first cavity 53 along a second direction, wherein the first direction and the second direction intersect.

[0051] In other embodiments, the first cavity 53 and the second cavity 54 can also be arranged in other ways, and are not limited to being distributed sequentially in a certain direction. For example, the first cavity 53 can partially enclose the second cavity 54, or the second cavity 54 can partially enclose the first cavity 53, etc. In this case, the first opening 55 can also be connected to the first cavity 53 and the second cavity 54 in other directions, and the second opening 56 can also be connected to the first cavity 53 in other directions. It is only necessary to select a suitable position for the opening on the mounting part 51.

[0052] When the first cavity 53 and the second cavity 54 are distributed along the first direction, the second opening 56 can also be connected to the first cavity 53 along other directions, for example, along the first direction. In this case, the second opening 56 can be located on the right side of the first cavity 53 (within the first direction). Figure 3 The mounting part 51 (based on the reference) is installed on it.

[0053] For example, the first direction and the second direction are parallel to the circuit board 10, and the first direction is perpendicular to the second direction. In the accompanying drawings of this specification, the x-axis is the second direction, the y-axis is the first direction, and the z-axis is the direction perpendicular to the circuit board 10.

[0054] In one embodiment, the circuit board 10 has a first surface and a second surface facing away from each other. The mounting part 51 and the photonic chip 20 are both mounted on the first surface of the circuit board 10. Coplanar mounting ensures the consistency of stress in the optical system in the initial state and achieves an ideal and stable reference plane. The carrier part 52 has a third surface and a fourth surface facing away from each other. The laser device 31 and the transmitting fiber 41 are mounted on the third surface. The third surface is parallel to the first surface, and its parallelism and flatness errors do not exceed 0.03 mm, ensuring the coupling accuracy of the laser device 31, the photonic chip 20 and the transmitting fiber 41.

[0055] In one embodiment, the optical transmission assembly composed of photonic chip 20, laser device 31, transmitting fiber 41, and fixing block 50 can be configured in multiple groups; for example, four groups are configured. The photonic chip 20 has 8 channels, with a single channel transmission rate of 200G, and the entire optical module has a high transmission rate of 6.4T. In other embodiments, the optical transmission assembly composed of photonic chip 20, laser device 31, transmitting fiber 41, and fixing block 50 can also be configured in other quantities. For example, if a single-channel 200G, 16-channel photonic chip 20 is used, only two groups of optical transmission assemblies are needed to meet the same 6.4T transmission rate requirement.

[0056] Preferably, a resin-copper composite layer may be embedded inside the circuit board 10, and a copper layer is disposed in the middle layer, the thickness of which is approximately 30 mm. This increases the lateral thermal conductivity of circuit board 10 to 1500 W / m·K and reduces thermal stress by 25%. Preferably, circuit board 10 uses the MASP process and the pads use the ENEPIG surface treatment process, which significantly improves its reliability and bonding performance.

[0057] The circuit board 10 has a through hole 11, and the support part 52 is disposed in the through hole 11. The circuit board 10 with a width of at least 2 mm is reserved around the through hole 11. If the circuit board 10 has multiple fixing blocks 50 and through holes 11, the distance between any two through holes 11 must be at least greater than 4 mm to ensure the structural strength of the circuit board 10.

[0058] In one embodiment, the fixing block 50 is a metal fixing block, preferably a tungsten-copper alloy block. In other embodiments, the fixing block 50 can also be a ceramic fixing block. By using high-performance materials with high thermal conductivity, low thermal expansion coefficient, and strong structural stability, such as tungsten-copper alloy and ceramic, the heat dissipation capacity of the photonic chip 20, laser device 31, etc., can be improved while ensuring the stability of the optical path at the transmitting end.

[0059] Preferably, the mounting part 51 and the bearing part 52 are integrally formed, which ensures good mechanical strength.

[0060] Combination Figures 3-5 As shown, the mounting portion 51 includes an extension extending to the outside of the support portion 52, and the side of the extension facing the circuit board 10 is recessed to form a first opening 55.

[0061] As can be seen, the mounting part 51 not only strengthens and fixes the circuit boards 10 on both sides of the photonic chip 20, but also restricts the displacement of the photonic chip 20 from both the vertical and horizontal directions, greatly ensuring the stability of the optical path and achieving a coupling yield of over 97%. At this time, the mounting part 51 and the photonic chip 20 can also obtain a large contact area, further improving the heat dissipation capacity of the photonic chip 20.

[0062] In one embodiment, a thermally conductive layer (not shown) is provided between the mounting portion 51 and the photonic chip 20 within the first opening 55 to enhance thermal conduction between them. Since the photonic chip 20 is flip-chip bonded to the circuit board 10, the thermally conductive layer is located on the back side of the photonic chip 20, avoiding the risk of contaminating the waveguide and modulator. The thermal conductivity of the thermally conductive layer is preferably greater than 3 W / m·K, which can reduce the thermal resistance of the photonic chip 20 from 2.5 °C / W to 1.2 °C / W.

[0063] Combination Figures 3-5As shown, in one embodiment, the support portion 52 located in the second cavity 54 has a third opening 57 on the side away from the first opening 55, the circuit board 10 is partially located in the third opening 57, and the laser device 31 is electrically connected to the circuit board 10 in the third opening 57.

[0064] By using the through-hole 11 to conform the shape of the carrier portion 52, the circuit board 10 can be filled into the third opening 57. Only by placing the pads on the circuit board 10 located in the third opening 57, wire bonding can be performed between the laser device 31 and the circuit board 10, which greatly shortens the wire length and signal transmission path.

[0065] Combination Figures 3-4 As shown, in one embodiment, the support portion 52 below the second cavity 54 is recessed relative to the support portion 52 below the first cavity 53, so that the heat on the laser device 31 can not only diffuse from the bottom to the support portion 52, but also further diffuse from the side to the support portion, thereby improving the heat dissipation capacity.

[0066] Combination Figures 1-5 As shown, the mounting part 51 has a mounting area on the side surface facing the circuit board 10. The projection area of ​​the mounting area on the circuit board 10 is outside the projection area of ​​the carrier part 52 on the circuit board 10. At least a portion of the mounting area is provided with an adhesive layer between it and the circuit board 10.

[0067] Specifically, the mounting area includes a first region that is bonded to the circuit board 10 and a second region that is recessed relative to the first region, with the adhesive layer located at least in the second region. More specifically, the adhesive layer is located in both the second and first regions.

[0068] Furthermore, multiple first and second regions are spaced apart, and the first and second regions extend in the same direction. Specifically, the first and second regions extend in a first direction.

[0069] The recessed second area increases the bonding area between the adhesive layer and the mounting part 51, making the fit between the mounting part 51 and the circuit board 10 more secure and tight.

[0070] Preferably, the depth of the second region relative to the first region is 0.05mm to 0.2mm.

[0071] Preferably, the adhesive layer is an adhesive with a shear strength greater than 15 MPa, which ensures the installation strength between the fixing block 50 and the circuit board 10.

[0072] Preferably, the minimum thickness of the fixing block 50 in the direction perpendicular to the circuit board 10 is greater than or equal to 0.9 mm, which ensures the overall strength of the fixing block 50.

[0073] Preferably, the thickness of the mounting portion 51 in the direction perpendicular to the circuit board 10 is 1.5mm to 1.7mm.

[0074] like Figure 1 As shown, in one embodiment, the optical module further includes a driver chip 60. The driver chip 60 is used to drive the laser device 31. The driver chip 60 can be flip-chip bonded to the circuit board 10 or the photonic chip 20, shortening the signal transmission path. Since both the photonic chip 20 and the driver chip 60 use flip-chip bonding technology to achieve electrical connection with the circuit board 10, the signal transmission path is shortened by more than 50%, and the heat dissipation efficiency is also improved.

[0075] like Figure 6 As shown, in one embodiment, the optical module further includes a first substrate 58 and a second substrate 59. The first substrate 58 is disposed on the surface of the carrier portion 52 within the first cavity 53, and the transmitting optical fiber 41 is mounted on the first substrate 58. The second substrate 59 is disposed on the surface of the carrier portion 52 within the second cavity 54, and the laser device 31 is mounted on the second substrate 59.

[0076] Preferably, both the first substrate 58 and the second substrate 59 are made of ceramic substrates. Ceramic substrates have high flatness and thus a high heat dissipation coefficient, and can serve as optical platforms and electrical circuits.

[0077] Preferably, the thickness of both the first substrate 58 and the second substrate 59 is 0.1 mm to 0.5 mm.

[0078] Preferably, the thermal conductivity of both the first substrate 58 and the second substrate 59 is greater than or equal to 200 W / m·K.

[0079] Preferably, the support portion 52 is further provided with a first receiving groove for receiving the first substrate 58 and a second receiving groove for receiving the second substrate 59.

[0080] like Figure 6 As shown, in one embodiment, the optical module further includes a focusing lens 32 and an isolator 33 mounted on a carrier portion 52 within the second cavity 54. The focusing lens 32 and the isolator 33 are sequentially disposed between the laser device 31 and the photonic chip 20.

[0081] The focusing lens 32 is used to converge the laser emitted by the laser device 31 through the isolator 33 onto the input waveguide end face of the photonic chip 20. A single focusing lens 32 simultaneously performs the dual tasks of focusing and converging diverging light, resulting in a simple and compact structure with a shorter optical path (the total optical path length is nearly 50% shorter than that of a traditional dual-lens system), significantly saving space and further improving integration. Lens costs are reduced by 50%, coupling processes are reduced to two steps, and coupling process efficiency is improved by 33%. However, the single focusing lens 32 has poor tolerance to tolerances and requires a stable optical system.

[0082] The structural design of the fixing block 50 can effectively fix the photonic chip 20 and the laser device 31, thereby fixing their relative positions, improving the tolerance of the single focusing lens 32 to tolerances, and improving the coupling yield.

[0083] Furthermore, the focusing lens 32 is mounted on the second substrate 59, further improving the stability of the optical path. The isolator 33 can be directly mounted on the carrier 52 or on the second substrate 59. The optical axes of the laser device 31, the focusing lens 32, the isolator 33, and the photonic chip 20 are located in the same plane, and the optical axes of the laser device 31 and the focusing lens 32 can be 30° away from the incident waveguide of the photonic chip 20 in the first direction. ~70 The offset is used to correct the deflection effect of the isolator 33 on the light.

[0084] Multiple sets of laser device 31, focusing lens 32, and isolator 33 can be configured according to actual needs. In such cases... Figure 6 In one specific embodiment shown, the photonic chip 20 has two input channels, and to achieve eight-channel output through two 1-to-4 waveguides, it requires two single-wavelength 200G laser sources. Therefore, two sets of laser devices 31, focusing lenses 32, and isolators 33 are provided. Figure 7 In another specific embodiment shown, the photonic chip 20 has four input channels and achieves 16-channel output through four 1-to-4 waveguides. This requires four single-wavelength 200G laser sources, so four sets of laser devices 31, focusing lenses 32, and isolators 33 are provided. The sets of laser devices 31, focusing lenses 32, and isolators 33 are arranged sequentially along the first direction.

[0085] like Figure 6 As shown, in one embodiment, the optical module further includes a thermistor 34 mounted on a carrier portion 52 within the second cavity 54. The thermistor 34 is electrically connected to the circuit board 10 and forms an NTC temperature sensor to meet the temperature monitoring requirements of the optical module. Specifically, the thermistor 34 can be mounted close to the laser device 31 on the second substrate 59.

[0086] In one embodiment, multiple transmitting optical fibers 41 are provided, and the multiple transmitting optical fibers 41 are coupled to each output channel of the photonic chip 20. The specific number of transmitting optical fibers 41 can be determined by the number of channels of the photonic chip 20. The multiple transmitting optical fibers 41 are arranged to form a ribbon optical cable; the optical module may also include a third substrate 42 and a first cover plate (not shown in the figure). The bottom surface of the third substrate 42 has multiple first fixing grooves. Preferably, the first fixing grooves are V-shaped grooves. The transmitting optical fibers 41 can be bonded to the first fixing grooves of the third substrate 42 by UV curing adhesive and pressed and fixed by the first cover plate. The third substrate 42 and the first cover plate are preferably quartz glass plates.

[0087] Preferably, the end face of the transmitting optical fiber 41 is ground into an inclined plane at an 8° angle to the axis of the transmitting optical fiber 41, which can reduce return loss and improve the stability of the system.

[0088] Combination Figures 8-9 As shown, in one embodiment, the optical module further includes an optical receiving component electrically connected to the circuit board 10.

[0089] The optical receiving component includes a photodetector 72, a transimpedance amplifier 73, and a receiving optical fiber 71. The photodetector 72 is optically coupled to the receiving optical fiber 71 to generate an electrical signal based on the optical signal on the receiving optical fiber. The transimpedance amplifier 73 is electrically connected to the photodetector 72 and the circuit board 10. The transimpedance amplifier 73 amplifies the weak electrical signal generated by the photodetector 72 to facilitate subsequent signal processing. The photodetector 72 can be a PIN photodiode.

[0090] Furthermore, the photodetector 72 is flip-chip soldered onto the surface of the transimpedance amplifier 73 to achieve electrical connection, reducing the high-speed signal transmission path by approximately 80% compared to the traditional wire bonding method.

[0091] In one embodiment, multiple receiving optical fibers 71 are provided, and the multiple receiving optical fibers 71 are coupled to each input channel of the photodetector 72. The specific number of receiving optical fibers 71 can be determined by the number of channels of the photodetector 72. The multiple receiving optical fibers 71 are arranged to form a ribbon optical cable.

[0092] like Figure 9 As shown, the optical receiving assembly may further include a fourth substrate 74, a fifth substrate 75, and a second cover plate 76. The bottom surface of the fourth substrate 74 has multiple second fixing grooves. Preferably, the second fixing grooves are V-shaped grooves. The receiving optical fiber 71 can be bonded to the second fixing grooves of the fourth substrate 74 using UV-curable adhesive and then pressed and fixed by the second cover plate 76. The fourth substrate 74 and the second cover plate are preferably quartz glass plates. The fourth substrate 74 and the second cover plate 76 are mounted on the fifth substrate 75, which is mounted on the circuit board 10. The fifth substrate 75 is preferably a ceramic plate.

[0093] In one embodiment, multiple optical receiving components are provided; all multiple optical receiving components are disposed on the second surface of the circuit board 10, thereby achieving a significant increase in integration. In other embodiments, the optical receiving components may also be disposed on the first surface of the circuit board 10, or on both the first and second surfaces of the circuit board 10; or only one optical receiving component may be provided. The optical receiving components may be positioned at the end of the circuit board 10 near the gold fingers to ensure minimal loss during high-speed electrical signal transmission.

[0094] The optical module of this invention not only ensures the stability of the optical path system and high heat dissipation efficiency, but also has the advantage of a simple assembly process. For example, assembling the optical module only requires the following simple process steps:

[0095] First, the circuit board 10 and the fixing block 50 can be pre-treated: the circuit board 10 is ultrasonically cleaned with alcohol to remove large particulate contaminants, and then placed in an oven to dry; the surface of the fixing block 50 is plasma cleaned to remove molecular-level contaminants and improve the interfacial bonding force.

[0096] Next, flip-chip bonding is performed: using a high-precision DB device, the photonic chip 20 and the driver chip 60 are flip-chip bonded to the surface of the circuit board 10, the driver chip 60 is flip-chip bonded to the surface of the photonic chip 20, and the photodetector 72 is flip-chip bonded to the surface of the transimpedance amplifier 73; due to the different coefficients of thermal expansion, epoxy resin liquid underfill material can also be injected between the photonic chip 20 and the circuit board 10, and between the photodetector 72 and the transimpedance amplifier 73.

[0097] Next, the bonding and fixing block 50 is bonded: the glue is applied to the groove area of ​​the mounting part 51 by the dispensing equipment (the amount of glue is 0.02g / mm²), and the tooling fixture is used to align and mount it with the circuit board 10. After baking and curing, the bonding strength is at least 15MPa, and the parallelism error can be controlled to be no more than 0.02mm.

[0098] Next, the carrier 52 is mounted: the isolator 33, the first substrate 58 and the second substrate 59 are attached to the carrier 52 using a DB device, and then placed in an oven to bake until the adhesive is cured.

[0099] Next, the laser device 31 is mounted: the laser device 31 is mounted onto the second substrate 59 using a DB device, and then placed in an oven for baking until the adhesive is cured.

[0100] Next, the light receiving components are mounted: the fifth substrate 76, the transimpedance amplifier 73 and the photodetector 72 are mounted onto the surface of the circuit board 10 using a DB device, and then placed in an oven to bake until the adhesive is cured.

[0101] Next, the laser device 31 and the transimpedance amplifier 73 are connected by gold wire bonding using a wire bonding device. The third opening 57 facilitates wire bonding of the laser device 31.

[0102] Next, the position of the focusing lens 32 is adjusted using an active alignment device. When the incident light received power of the photonic chip 20 is detected to be at its maximum, the focusing lens 32 is fixed with optical glue.

[0103] Next, the position of the transmitting optical fiber 41 is adjusted using an active alignment device. When the optical fiber receives the maximum optical power, the transmitting optical fiber 41 is fixed with optical glue.

[0104] Finally, the position of the receiving optical fiber 71 is adjusted using an active alignment device. When the responsivity of the photodetector 72 is at its maximum, the receiving optical fiber 71 is fixed with optical glue.

[0105] As can be seen, the above assembly process uses all existing mature PCB technology, without the need to introduce additional process design, the steps are simple and the manufacturing efficiency is high.

[0106] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0107] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A fixing block applied to an optical module, the optical module comprising a circuit board, a photonic chip, a laser device and a transmitting optical fiber, characterized in that, The fixing block comprises a bearing part embedded in the circuit board and a mounting part attached to the circuit board, the mounting part is connected with the bearing part and forms a receiving cavity with the bearing part, the receiving cavity comprises a first cavity and a second cavity connected with each other, the fixing block has a first opening connected with the first cavity and the second cavity and a second opening connected with the first cavity, the laser device is located in the second cavity and is mounted on the bearing part, one end of the transmitting optical fiber is located in the first cavity and is mounted on the bearing part, and the transmitting optical fiber penetrates through the second opening, the photon chip is mounted on the circuit board and at least partially located in the first opening.

2. The fixed block according to claim 1, wherein The first cavity and the second cavity are distributed along a first direction, the first opening is connected with the first cavity and the second cavity along a second direction, and the second opening is connected with the first cavity along the second direction, and the first direction intersects with the second direction.

3. The fixed block according to claim 2, wherein The mounting part comprises an extension part extending to the outside of the bearing part, and the extension part is recessed towards one side of the circuit board to form a first opening.

4. The fixed block according to claim 1, wherein The bearing part located in the second cavity is provided with a third opening on the side away from the first opening, and the circuit board is partially located in the third opening, and the laser device is electrically connected with the circuit board in the third opening.

5. The fixed block of claim 1, wherein The surface of the mounting part towards the circuit board has an attachment area, the projection area of the attachment area on the circuit board is located outside the projection area of the bearing part on the circuit board, and at least part of the attachment area is provided with an adhesive layer between the attachment area and the circuit board.

6. The fixed block according to claim 5, wherein The attachment area comprises a first area attached to the circuit board and a second area recessed relative to the first area, and the adhesive layer is located at least in the second area.

7. The fixed block according to claim 6, wherein The first area and the second area are spaced apart by a plurality of areas, and the first area and the second area extend in the same direction.

8. The fixed block of claim 6, wherein, The recess depth of the second area relative to the first area is 0.05mm-0.2mm.

9. The fixed block of claim 5, wherein, The bearing part below the second cavity is recessed relative to the bearing part below the first cavity.

10. The fixed block of claim 1, wherein The fixing block is a metal fixing block or a ceramic fixing block; and / or, The minimum thickness of the fixing block in the direction perpendicular to the circuit board is greater than or equal to 0.9mm.

11. An optical module characterized by comprising: The fixing block comprises a circuit board, a photon chip, a laser device, a transmitting optical fiber and a fixing block according to any one of claims 1-10, the photon chip and the laser device are electrically connected with the circuit board, and the laser device and the transmitting optical fiber are optically coupled with the photon chip.

12. The optical module of claim 11, wherein, A heat-conducting layer is provided between the mounting part and the photon chip in the first opening.

13. The optical module of claim 11, wherein, The surface of the bearing part in the first cavity is provided with a first substrate, and the transmitting optical fiber is mounted on the first substrate; and / or, The surface of the bearing part in the second cavity is provided with a second substrate, and the laser device is mounted on the second substrate.

14. The optical module according to claim 13, characterized by The first substrate and / or the second substrate are ceramic substrates; and / or, The thickness of the first substrate and / or the second substrate is 0.1mm-0.5mm; and / or, The thermal conductivity of the first substrate and / or the second substrate is greater than or equal to 200 W / m·K.

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