Packaging structure, optical module and optical system

Abstract

The present application provides a packaging structure, an optical module and an optical system. The packaging structure comprises a photonics integrated circuit, a fiber array, and a substrate, wherein a spot size converter is arranged in the photonic chip and is composed of a cantilever beam waveguide and a first groove; the fiber array comprises an optical fiber, a base plate and a cover plate, the base plate comprising a second groove for accommodating the optical fiber, and the cover plate being snap-fitted with the base plate; and the photonic chip is arranged on an upper surface of the substrate, the base plate or the cover plate is arranged on the upper surface of the substrate, and the cantilever beam waveguide is coupled to the optical fiber. In the packaging structure, the arrangement of both the photonics integrated circuit and the fiber array on the upper surface of the substrate and the elimination of the use of additional support members can ensure the mechanical stability of the packaging structure, which reduces stress variations near the cantilever beam waveguide in the packaging structure caused by temperature changes, displacement or external forces, thereby achieving low-stress packaging.

Description

Packaging structure, optical module and optical system

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 1, 2023, with application number 202311443484.2, and the priority of the Chinese patent application entitled "A packaging structure, optical module and optical system". Technical Field

[0002] The present application relates to the field of optical communications, and in particular to a packaging structure, an optical module, and an optical system. Background Art

[0003] With the rapid development of big data and cloud computing, data center network traffic is experiencing a rapid growth, posing significant challenges to data center networks and optical interconnect technologies. Silicon photonics technology utilizes silicon as the foundational material for optical devices and leverages advanced manufacturing processes to build optical components such as optical waveguides, modulators, and optical switches on photonic chips. These devices enable the generation, transmission, regulation, and detection of optical signals.

[0004] The packaging of photonic integrated circuits (PICs) and fiber arrays (FAs) is a key technical challenge in silicon photonics technology. Because the mode field diameter of the waveguides in photonic chips is small and mismatched with that of standard optical fibers, direct coupling of the waveguides to the optical fibers results in significant coupling losses. As a packaging method, a spot size converter (SSC) can be placed at the edge of the photonic chip, or at one end of the chip, to align the waveguide's pattern with the optical fiber's pattern. The SSC can be in the form of a cantilever beam. The bottom of the SSC is etched to form a first groove, and the waveguide is suspended relative to the groove, forming a cantilever waveguide. However, cantilever structures are stress-sensitive. For example, changes in ambient temperature, external forces, and movement of the packaging structure can all induce stress on the cantilever waveguide, altering its optical transmission characteristics. High stress can even damage the waveguide's mechanical structure. Therefore, achieving low-stress packaging for end-face coupling structures remains an urgent challenge.

[0005] Summary of the Invention

[0006] The present application provides a packaging structure, an optical module, and an optical system, which realize low-stress packaging of an end-face coupling structure by arranging a photonic chip and an optical fiber array on the upper surface of the same substrate.

[0007] In a first aspect, a packaging structure is provided, comprising a photonic chip, an optical fiber array, and a substrate. The photonic chip is provided with a spot size converter, which is composed of a cantilever waveguide and a first groove, wherein a gap is formed between the cantilever waveguide and the first groove. The optical fiber array comprises optical fibers, a base plate, and a cover plate, wherein the base plate includes a second groove for accommodating the optical fibers, and the cover plate is fastened to the base plate. The photonic chip is disposed on the upper surface of the substrate, and the base plate or the cover plate is disposed on the upper surface of the substrate, and the cantilever waveguide is coupled to the optical fibers. In this packaging structure, by disposing the photonic chip and the optical fiber array together on the upper surface of the substrate and avoiding the use of additional support members, such as spacers, the mechanical stability of the packaging structure is ensured, stress changes near the cantilever waveguide caused by temperature changes, displacement, external forces, etc. are reduced, and low-stress packaging is achieved.

[0008] In conjunction with the first aspect, in certain implementations of the first aspect, coupling the cantilever waveguide to the optical fiber includes: butting the distal end of the cantilever waveguide against the distal end of the optical fiber. Thus, in a packaging solution in which the cantilever waveguide is directly coupled to the optical fiber, by disposing the photonic chip and the optical fiber array on the top surface of the same substrate, excessive localized stress in the coupling region between the cantilever waveguide and the optical fiber due to temperature changes, displacement, external force, and the like is avoided, thereby reducing packaging losses.

[0009] In conjunction with the first aspect, in certain implementations of the first aspect, the projections of the optical fiber and the photonic chip on the substrate do not overlap. This prevents the optical fiber from overextending into the photonic chip, which could cause mechanical damage such as breakage, and reduces stress between the cantilever waveguide and the optical fiber, thereby reducing packaging losses.

[0010] In conjunction with the first aspect, in certain implementations of the first aspect, the projections of the base plate and the photonic chip on the substrate are spaced apart, and the optical fiber extends beyond the base plate at an end adjacent to the photonic chip. By moving the base plate back, stress between the cantilever beam waveguide and the optical fiber can be reduced, thereby reducing packaging loss.

[0011] In conjunction with the first aspect, in certain implementations of the first aspect, the projections of the cover plate and the photonic chip on the substrate are spaced apart, and the optical fiber extends beyond the cover plate at the end adjacent to the photonic chip. By moving the cover plate backward, fiber identification and glue dispensing are facilitated during the fiber array fabrication process, optimizing the fabrication process. This also reduces stress between the cantilever waveguide and the optical fiber, lowering packaging losses.

[0012] In conjunction with the first aspect, in certain implementations of the first aspect, the projections of the base plate and the photonic chip on the substrate are spaced apart, the projections of the cover plate and the photonic chip on the substrate are spaced apart, and the optical fiber extends beyond the base plate and the cover plate at an end adjacent to the photonic chip. By moving the base plate and the cover plate backward, fiber identification and glue dispensing can be facilitated during the fiber array preparation stage, optimizing the preparation process. This also reduces stress between the cantilever beam waveguide and the optical fiber, reducing packaging losses.

[0013] In conjunction with the first aspect, in certain implementations of the first aspect, the substrate is made of fused quartz, Invar, Kovar, silicon carbide, silicon, aluminum oxide, aluminum nitride, or tungsten-copper alloy; and / or the thermal expansion rate of the substrate is 0.3-10 ppm / °C. This ensures that the package structure maintains low stress and mechanical stability in all three temperature environments. In some implementations, the substrate is made of aluminum oxide, aluminum nitride, or tungsten-copper alloy; and / or the thermal expansion rate of the substrate is 4-8 ppm / °C. This further ensures that the expansion rate of the substrate material matches that of the optical fiber array and photonic chip, ensuring that the package structure maintains low stress and mechanical stability in all three temperature environments.

[0014] In conjunction with the first aspect, in certain implementations of the first aspect, a first bonding portion is provided at the coupling point between the cantilever waveguide and the optical fiber, wherein: the first bonding portion is made of silicone; and / or the modulus of the first bonding portion is less than 1 MPa; and / or the refractive index of the first bonding portion is 1.35-1.45; and / or the thermal expansion coefficient of the first bonding portion is less than 100 ppm / °C. This confines optical signal transmission to the space between the cantilever waveguide and the optical fiber, achieving a "soft connection" between the cantilever waveguide and the optical fiber, reducing local stress and preventing local stress buildup in the cantilever waveguide or optical fiber caused by temperature changes, displacement, external forces, and other factors within the package structure. Furthermore, low stress in the package structure is ensured under "three-temperature" conditions.

[0015] In conjunction with the first aspect, in certain implementations of the first aspect, a second adhesive portion is provided in the first groove, the second adhesive portion contacts the cantilever waveguide, or the second adhesive portion covers the cantilever waveguide, wherein: the second adhesive portion is made of silicone; and / or the modulus of the second adhesive portion is less than 1 MPa; and / or the refractive index of the second adhesive portion is 1.35-1.45; and / or the thermal expansion coefficient of the second adhesive portion is less than 100 ppm / °C. This protects the cantilever waveguide, reduces local stress, and prevents mechanical damage to the cantilever waveguide caused by temperature changes, displacement, and external forces. Furthermore, the optical signal is confined to the cantilever waveguide for transmission, and the second adhesive portion is ensured to undergo significant thermal expansion in a "three-temperature" environment, thereby preventing mechanical damage to the cantilever waveguide.

[0016] In conjunction with the first aspect, in certain implementations of the first aspect, an adhesive layer is provided between the optical fiber array and / or photonic chip and the substrate, wherein: the adhesive layer is composed of epoxy resin or acrylic acid; and / or the adhesive layer has a shrinkage rate of less than 0.3%. This prevents displacement of the optical fiber array and / or photonic chip, thereby reducing packaging losses. The adhesive layer 160 can be composed of epoxy resin or acrylic acid, thereby preventing displacement of the optical fiber array and / or photonic chip, thereby reducing packaging losses.

[0017] In conjunction with the first aspect, in certain implementations of the first aspect, a glue guide groove is provided on the substrate, and is located between the photonic chip and the optical fiber array. The glue guide groove is used to guide glue when it is dripped onto the first and second bonding portions during the packaging stage, thereby preventing the glue on the first and second bonding portions from contacting with the glue on the bonding layer, which could cause contamination.

[0018] In conjunction with the first aspect, in certain implementations of the first aspect, the spot converter includes N cantilever waveguides, the optical fiber array includes N optical fibers, the N cantilever waveguides correspond one-to-one with the N optical fibers, and the cantilever waveguides in the N cantilever waveguides are mutually coupled with their corresponding optical fibers, where N is a positive integer. In some implementations, N is a positive integer greater than or equal to 2. In the case of a multi-channel package structure, by disposing the photonic chip and the optical fiber array on the same substrate, the stability of the package structure is increased, high stress can be avoided at the coupling portion between the N optical fibers and the N cantilever waveguides, and constraints on the optical fibers in the optical fiber array can be reduced.

[0019] In conjunction with the first aspect, in certain implementations of the first aspect, the packaging structure includes M optical fiber arrays, the photonic chip includes M spot mode converters, the M optical fiber arrays correspond to the M spot mode converters one-to-one, the optical fiber arrays in the M optical fiber arrays are mutually coupled with the corresponding spot mode converters, and M is a positive integer. In some implementations, M is a positive integer greater than or equal to 2. The packaging structure can be a co-packaging structure, thereby shortening the transmission distance of the optical signal, reducing packaging loss, and lowering system cost and energy loss.

[0020] In a second aspect, a packaging structure and an optical component including the first aspect and any possible implementation of the first aspect are provided. The optical component is optically connected to the packaging structure, and the optical component is used to receive and / or send optical signals.

[0021] In a third aspect, an optical system is provided, comprising an optoelectronic device and the optical module of the second aspect or any possible implementation, wherein the optoelectronic device is connected to the optical module, and the optoelectronic device is any one of an optical switch, a fiber optic router, and a fiber optic network card. The optoelectronic device may include multiple ports, each of the multiple ports corresponding to an optical transmission channel, and the ports of the multiple ports are connected to the optical module to achieve multi-channel, high-speed data transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG1 is a schematic diagram of a packaging structure provided in an embodiment of the present application.

[0023] FIG2 is a pattern spot converter provided in an embodiment of the present application.

[0024] FIG3 is a schematic diagram of another packaging structure provided in an embodiment of the present application.

[0025] FIG4 is a schematic diagram of another packaging structure provided in an embodiment of the present application.

[0026] FIG5 is a schematic diagram of another packaging structure provided in an embodiment of the present application.

[0027] FIG6 is a schematic diagram of an optical module provided in an embodiment of the present application.

[0028] FIG7 is a schematic diagram of an optical system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] The technical solution in this application will be described below with reference to the accompanying drawings.

[0030] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the quantity of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features.

[0031] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0032] In the description of the embodiments of the present application, the terms "upper", "lower", "vertical", "horizontal", etc. indicate orientations or positional relationships that are defined relative to the orientations or positions of the components schematically placed in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative descriptions and clarifications, rather than indicating or implying that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. They may change accordingly according to changes in the orientation of the components placed in the drawings, and therefore cannot be understood as limitations on the present application.

[0033] The terms "including" and "having" and any variations thereof in the embodiments of the present application shown below are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or are inherent to these processes, methods, products or apparatus.

[0034] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. An embodiment or design described as "exemplary" or "for example" should not be construed as being more preferred or advantageous than other embodiments or designs. The use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete manner to facilitate understanding.

[0035] With the rapid development of big data and cloud computing, data center network traffic is experiencing a rapid growth, posing significant challenges to data center networks and optical interconnect technologies. Traditional data center networks employ electronic interconnect technologies, which are subject to limitations such as high power consumption, limited bandwidth, and high latency. To meet the demands of high bandwidth, low latency, and energy efficiency, silicon photonics technology has garnered significant attention. The core of silicon photonics technology is the use of silicon as the base material for optical devices. Advanced manufacturing processes enable the construction of optical components such as optical waveguides, modulators, and optical switches on photonic chips. These components enable the generation, transmission, control, and detection of optical signals. Compared to traditional optical devices, silicon photonics offers advantages such as low manufacturing cost, high integration density, and strong compatibility.

[0036] The packaging of photonic integrated circuits (PICs) and fiber arrays (FAs) is one of the key technical challenges in silicon photonics technology. Since the mode field diameter of the waveguide in the photonic chip is small and does not match the mode field diameter of a standard optical fiber, direct coupling of the waveguide to the optical fiber will result in significant coupling losses. Currently, the packaging structures for photonic chips and optical fibers can be divided into end-face coupled packaging structures and grating coupled packaging structures. The end-face coupled packaging structure refers to a packaging structure formed by directly or indirectly optically connecting the end face of the photonic chip to the end face of the optical fiber. The grating coupled packaging structure refers to a packaging structure formed by optically connecting the photonic chip and the optical fiber via a grating. Although the grating coupled packaging structure has advantages such as large tolerance and ease of assembly, the grating itself will produce optical signal loss. The end-face coupled packaging structure has become the predominant form of coupling packaging structure due to its advantages such as low packaging loss and small size.

[0037] As a packaging form of an end-face coupling structure, a spot size converter (SSC) can be set at the edge of the photonic chip, or it can also be understood as one end of the photonic chip, to match the waveguide spot with the optical fiber spot. The spot size converter can be in the form of a cantilever beam. The bottom of the cantilever beam spot converter is etched to form a first groove. The waveguide is suspended relative to the first groove to form a cantilever beam waveguide. The air in the first groove is used to confine the transmitted optical signal to the cantilever beam waveguide for transmission, thereby achieving mode field matching and reducing packaging losses. However, the cantilever beam structure is stress-sensitive. For example, changes in ambient temperature, the application of external forces, and the movement of the packaging structure may cause stress to act on the cantilever beam waveguide, which will cause the optical transmission characteristics of the cantilever beam waveguide to change. The high stress will further damage the mechanical structure of the waveguide. Therefore, how to achieve low-stress packaging of the end-face coupling structure is an urgent problem to be solved.

[0038] In view of this, embodiments of the present application provide a packaging structure, an optical module, and an optical system, which achieve low-stress packaging of an end-face coupling structure by arranging a photonic chip and an optical fiber array on the upper surface of the same substrate.

[0039] Figure 1 is a schematic diagram of a package structure provided by an embodiment of the present application. Figures 1(a), 1(b), and 1(c) illustrate side views of the package structure, and Figure 1(d) illustrates a top view of the package structure. As shown in Figure 1, the package structure may include a photonic chip 110, an optical fiber array 120, and a substrate 130.

[0040] The photonic chip 110 is provided with a spot mode converter. The spot mode converter is composed of a cantilever beam waveguide 113 and a first groove 112. The optical fiber array 120 includes an optical fiber 121. The photonic chip 110 is provided on the upper surface of a substrate 130, and the optical fiber array 120 is also provided on the upper surface of the substrate 130. The cantilever beam waveguide 113 is coupled to the optical fiber 121.

[0041] The cantilever waveguide 113 may specifically refer to the portion of the waveguide 111 that is suspended relative to the first groove 112. Alternatively, the cantilever waveguide 113 and the waveguide 111 may be separate optical components, with an optical element such as a coupler or beam splitter disposed between the cantilever waveguide 113 and the waveguide 111. This is not a limitation of the present application. A gap may exist between the cantilever waveguide 113 and the first groove 112, or the cantilever waveguide 113 and the first groove 112 may be spaced apart or not in contact. Furthermore, the first groove may also be referred to as an undercut.

[0042] The optical fiber array 120 may include a base plate 122 and a cover plate 123. A second groove may be provided in the base plate 122, and the second groove may be a V-groove. The V-groove is used to accommodate the optical fiber. The base plate 122 and the cover plate 123 are snapped together, and the snapping method may be glue bonding or other methods. The optical fiber array 120 is arranged on the upper surface of the substrate 130 as shown in FIG1 (a), which means that the cover plate 123 is arranged on the upper surface of the substrate 130, or as shown in FIG1 (b), which means that the cover plate 123 is arranged on the upper surface of the substrate 130. Alternatively, the optical fiber array 120 may also be assembled in other ways, and this application does not limit this.

[0043] The coupling connection between the cantilever waveguide 113 and the optical fiber 121 can specifically refer to a direct optical connection or an indirect optical connection between the cantilever waveguide 113 and the optical fiber 121. The indirect optical connection can refer to an adapter, lens, polymer waveguide, etc. being provided between the cantilever waveguide 113 and the optical fiber 121. In the case shown in FIG1 , the coupling connection between the cantilever waveguide 113 and the optical fiber 121 specifically refers to the butting of the end of the cantilever waveguide 113 with the end of the optical fiber 121. Alternatively, it can be understood as the butting of the end face of the cantilever waveguide 113 with the end face of the optical fiber 121, or the alignment or registration of the cantilever waveguide 113 with the optical fiber 121. Thus, in a packaging solution in which the cantilever waveguide is directly coupled to the optical fiber, by placing the photonic chip and the optical fiber array on the top surface of the same substrate, the problem of excessive local stress in the coupling region between the cantilever waveguide and the optical fiber due to temperature changes, displacement, external force, etc. is avoided, thereby reducing packaging losses.

[0044] The photonic chip 110 can be primarily composed of silicon, and the cantilever waveguide portion of the photonic chip 110 can be made of glass, i.e., silica. The cover plate 123 and base plate 122 of the optical fiber array 120 can also be made of glass. The spot size converter expands the spot size of the cantilever waveguide 113 to the same 9 μm as that of the optical fiber 121.

[0045] In the packaging structure shown in FIG1 , by placing the photonic chip and the optical fiber array together on the upper surface of the substrate and avoiding the use of additional support members, such as spacers, the mechanical stability of the packaging structure can be ensured, and stress changes near the cantilever beam waveguide caused by temperature changes, displacement, external force application, etc. in the packaging structure can be reduced, thereby achieving low-stress packaging.

[0046] In some implementations, the thermal expansion rate of the substrate 130 can be 0.3-10 ppm / °C, thereby ensuring that the expansion rate of the substrate material matches that of the optical fiber array and the photonic chip, thereby ensuring that the packaging structure can maintain low stress in a "three-temperature" environment, where "three temperatures" specifically refer to a low temperature of -40°C, a room temperature of 25°C, and a high temperature of 85°C. The material of the substrate 130 can be fused quartz, Invar, Kovar, silicon carbide, or silicon. In some implementations, the material of the substrate 130 can be alumina, aluminum nitride, or tungsten-copper alloy, and the thermal expansion rate of the substrate 130 can be 4-8 ppm / °C, thereby ensuring that the expansion rate of the substrate material matches that of the optical fiber array and the photonic chip, thereby ensuring that the packaging structure can maintain low stress in a "three-temperature" environment and ensuring the mechanical stability of the packaging structure.

[0047] In some implementations, as shown in FIG1(c), a first bonding portion 140 is provided at the coupling point between the cantilever waveguide and the optical fiber. The refractive index of the first bonding portion 140 is 1.35-1.45, thereby limiting the transmission of the optical signal between the cantilever waveguide and the optical fiber, further reducing the packaging loss. The modulus of the first bonding portion 140 can be less than 1 MPa, thereby achieving a "soft connection" between the cantilever waveguide and the optical fiber, reducing local stress, and avoiding packaging losses of the cantilever waveguide or optical fiber caused by temperature changes, displacement, external force application, etc. in the packaging structure. The thermal expansion coefficient of the first bonding portion 140 can be less than 100 ppm / °C, thereby ensuring that the packaging structure can maintain low stress in the "three-temperature" environment. The first bonding portion 140 can be made of silicone material, thereby limiting the transmission of the optical signal between the cantilever beam waveguide and the optical fiber, and realizing a "soft connection" between the cantilever beam waveguide and the optical fiber, reducing local stress, avoiding the increase of local stress in the cantilever beam waveguide or optical fiber caused by temperature changes, displacement, external force application, etc. in the packaging structure, and ensuring that the packaging structure can maintain low stress in the "three-temperature" environment.

[0048] In some implementations, as shown in FIG1(c), a second adhesive portion 150 is provided in the first groove, and the second adhesive portion 150 contacts the cantilever waveguide, or the second adhesive portion 150 covers the cantilever waveguide. The modulus of the second adhesive portion 150 can be less than 1 MPa, thereby protecting the cantilever waveguide, reducing local stress, and preventing mechanical damage to the cantilever waveguide caused by temperature changes, displacement, external force, etc. The refractive index of the second adhesive portion 150 can be 1.35-1.45, thereby confining the optical signal to the cantilever waveguide for transmission together with the air in the first groove. The thermal expansion coefficient of the second adhesive portion 150 can be less than 100 ppm / °C, thereby ensuring that the second adhesive portion undergoes significant thermal expansion in a "three-temperature" environment, thereby preventing mechanical damage to the cantilever waveguide. The second adhesive portion 150 can be made of silicone material to protect the cantilever waveguide, reduce local stress, and prevent mechanical damage to the cantilever waveguide caused by temperature changes, displacement, and external forces. It also confines the optical signal to the cantilever waveguide. Furthermore, it ensures that the second adhesive portion undergoes significant thermal expansion in a "three-temperature" environment, preventing mechanical damage to the cantilever waveguide. The thickness of the second adhesive portion below the cantilever waveguide can be the same as that above the cantilever waveguide, further ensuring stress balance within the cantilever waveguide.

[0049] In some implementations, as shown in FIG1(c), an adhesive layer 160 is provided between the optical fiber array and the substrate, and / or between the photonic chip and the substrate. The adhesive layer 160 can have a shrinkage rate of less than 0.3%, thereby preventing displacement of the optical fiber array and / or the photonic chip and reducing packaging losses. The adhesive layer 160 can be made of epoxy or acrylic resin, thereby preventing displacement of the optical fiber array and / or the photonic chip and reducing packaging losses.

[0050] In some implementations, as shown in (a), (b), (c), and (d) in FIG1 , the projections of the optical fiber 121 and the photonic chip 110 on the substrate 130 do not overlap, thereby preventing the optical fiber from excessively extending to the photonic chip, which could cause mechanical damage such as breakage of the optical fiber, and reducing the stress between the cantilever beam waveguide and the optical fiber, thereby reducing packaging losses.

[0051] The specific process of the spot pattern converter shown in Figure 1 is determined based on actual conditions. Figure 2 illustrates a spot pattern converter provided in an embodiment of the present application. The spot pattern converter comprises a cantilever waveguide 210, a first groove 220, and a support 230. The support 230 supports the cantilever waveguide 210, ensuring that the cantilever waveguide 210 and the first groove 220 are not in contact. Alternatively, the cantilever waveguide 210 can be suspended relative to the first groove 220, thereby confining the optical signal emitted from the optical fiber 121 to be transmitted within the cantilever waveguide 210.

[0052] In some implementations, the pattern converter includes N cantilever waveguides. In this case, the lateral dimension of the first groove 220 can be extended accordingly, and the bracket 230 is used to support the N cantilever waveguides. The optical fiber array includes N optical fibers, corresponding one-to-one to the N cantilever waveguides of the pattern converter. The cantilever waveguides in the N cantilever waveguides are coupled with the corresponding optical fibers, and N is a positive integer. In some implementations, N is a positive integer greater than or equal to 2. In the case where the packaging structure is a multi-channel packaging structure, by arranging the photonic chip and the optical fiber array on the same substrate, the stability of the packaging structure is increased, high stress can be avoided in the coupling part of the N optical fibers and the N cantilever waveguides, and the restriction on the optical fibers in the optical fiber array can be reduced. Using the packaging structure of the present application, an optical fiber with an outer diameter of 127μm and an inner diameter of 125μm can be used as the transmission medium of the optical signal to achieve a high-density lateral pitch arrangement scheme without using a conventional 250μm optical fiber.

[0053] FIG3 is a schematic diagram of another packaging structure provided by an embodiment of the present application. The packaging structure in FIG3 includes a photonic chip 310, an optical fiber array 320, a substrate 330, a spot pattern converter provided in the photonic chip, a first groove and a cantilever beam waveguide included in the spot pattern converter, and optical fibers, a bottom plate 322, and a cover plate 323 included in the optical fiber array 320. These structures are similar to those in FIG1 and are not further described here.

[0054] As shown in FIG3 , in the packaging structure, a glue guide groove 370 may also be provided on the substrate 330, located between the photonic chip 310 and the optical fiber array 320. The glue guide groove 370 is used to guide the glue when it is dripped onto the first and second adhesive portions 340 and 350 during the packaging stage, thereby preventing the glue on the first and second adhesive portions 340 and 350 from contacting with the glue on the adhesive layer 360, which could cause contamination.

[0055] FIG4 is a schematic diagram of another packaging structure provided by an embodiment of the present application. The packaging structure in FIG4 includes a photonic chip 410, an optical fiber array 420, a substrate 430, a spot pattern converter provided in the photonic chip, a first groove and a cantilever beam waveguide included in the spot pattern converter, and optical fibers, a bottom plate 422, and a cover plate 423 included in the optical fiber array 420. These structures are similar to those in FIG1 and are not further described here.

[0056] In some implementations, as shown in FIG4 (a), the projections of the cover plate 423 and the photonic chip 410 on the substrate 430 are spaced apart, and the optical fiber 421 extends beyond the cover plate 423 at one end adjacent to the photonic chip 410. By moving the cover plate 423 backward, optical fiber identification and glue dispensing can be facilitated during the preparation of the optical fiber array, thereby optimizing the preparation process. It can also reduce the stress between the photonic chip and the optical fiber and reduce packaging losses. In addition, when a first bonding portion 440, a second bonding portion 450, and an adhesive layer 460 are provided in the packaging structure, the bonding surface between the cover plate 423 and the photonic chip 410 in the first bonding portion 440 can be eliminated to prevent the glue from flowing out and contacting the glue in the adhesive layer 460 to cause contamination.

[0057] In some implementations, as shown in FIG4( b ), the projections of the bottom plate 422 and the photonic chip 410 on the substrate 430 are spaced apart, and the optical fiber 421 extends beyond the bottom plate 422 at one end adjacent to the photonic chip 410. By moving the bottom plate 422 backward, the stress between the cantilever beam waveguide and the optical fiber can be reduced, thereby reducing packaging loss. In addition, when the first adhesive portion 440, the second adhesive portion 450, and the adhesive layer 460 are provided in the packaging structure, the bonding surface between the cover plate 423 and the photonic chip 410 in the first adhesive portion 440 can be eliminated, thereby preventing glue from flowing out and contacting the glue in the adhesive layer 460, thereby preventing contamination.

[0058] In some implementations, as shown in (c) of FIG. 4 , the projections of the base plate 422 and the photonic chip 410 on the substrate 430 are spaced apart, and the projections of the cover plate 423 and the photonic chip 410 on the substrate 430 are spaced apart, and the optical fiber 421 extends beyond the base plate 422 and the cover plate 423 at one end adjacent to the photonic chip 410. By moving the base plate 422 and the cover plate 423 backward, it is possible to facilitate optical fiber identification and glue dispensing during the preparation of the optical fiber array, thereby optimizing the preparation process. It is also possible to reduce the stress between the cantilever beam waveguide and the optical fiber, thereby reducing packaging loss. In addition, when a first bonding portion 440, a second bonding portion 450, and an adhesive layer 460 are provided in the packaging structure, the bonding surface between the cover plate 423 and the photonic chip 410 in the first bonding portion 440 can be eliminated, thereby preventing the glue from flowing out and contacting the glue in the adhesive layer 460, thereby causing contamination.

[0059] Figure 5 is a schematic diagram of another packaging structure provided by an embodiment of the present application. As shown in Figure 5, the packaging structure includes M optical fiber arrays 520, and the photonic chip 510 includes M spot mode converters. The M optical fiber arrays 520 correspond one-to-one to the M spot mode converters, and the optical fiber arrays in the M optical fiber arrays are mutually coupled with the corresponding spot mode converters, where M is a positive integer. In some implementations, M is a positive integer greater than or equal to 2, and the packaging structure can be a coupled package optics (CPO) structure, thereby shortening the transmission distance of the optical signal, reducing packaging loss, and lowering system cost and energy loss.

[0060] It should be understood that FIG5 only illustrates the case where M is equal to 4 and should not limit the specific form of the packaging structure. It should be understood that FIG5 only illustrates the case where the M optical fiber arrays 510 and the photonic chip 510 are simultaneously disposed on the upper surface of the substrate 530. In addition, the optical fiber arrays of the M optical fiber arrays 520 may also be partially disposed on the upper surface of the substrate 530, and this application does not impose any limitation on this.

[0061] In some implementations, the optical fiber array in the M optical fiber arrays includes one optical fiber, and the spot mode converter in the M spot mode converters includes a cantilever beam waveguide. In this case, the optical fiber array and the spot mode converter are specifically used for single-channel optical signal transmission.

[0062] In some implementations, the optical fiber arrays in the M optical fiber arrays include N optical fibers, and the spot pattern converters in the M spot pattern converters include N cantilever beam waveguides, where N is a positive integer greater than or equal to 2. Each of the M optical fiber arrays can include the same or different number of optical fibers, and correspondingly, each of the M spot pattern converters can include the same or different number of cantilever beam waveguides. In this case, the optical fiber arrays and spot pattern converters are specifically configured for multi-channel optical signal transmission.

[0063] Figure 6 is a schematic diagram of an optical module provided in an embodiment of the present application. As shown in Figure 6, the optical module may include an optical component 610 and a packaging structure 620, the optical component 610 is optically connected to the packaging structure 620, and the optical component 610 is used to receive and / or send optical signals. The specific configuration of the packaging structure 620 is shown in Figures 1 to 5. Among them, when the optical component 610 is used to send an optical signal, the optical component 610 may include a light source, a modulator, a filter, etc. When the optical component 610 is used to receive an optical signal, the optical component 610 may include a processor, a detector, etc. In some implementations, the optical component 610 includes light sources of multiple wavelengths, and the corresponding packaging structure 620 is used to send and / or receive optical signals of multiple wavelengths.

[0064] The components of the optical assembly can be incorporated into the photonic chip within the package structure, or the components of the optical assembly and the photonic chip or fiber array within the package structure can be discrete components. The specific form of the optical module is determined based on actual conditions. The optical connection between the optical assembly 610 and the package structure 620 can be a direct optical connection or an indirect optical connection. The indirect optical connection can refer to the provision of optical elements such as couplers and beam splitters between the components of the optical assembly 610 and the photonic chip or fiber array within the package structure 620.

[0065] In some implementations, the optical module further includes a printed circuit board (PCB). The PCB is electrically connected to the photonic chip in the package structure 620. The specific electrical connection method can be through wires, flat-wire welding, wire bonding, etc. The PCB can be used to process the optical signals sent and / or received by the photonic chip. For example, the PCB is used to transmit electrical signals, and the photonic chip is used to convert the electrical signals into optical signals for transmission. Alternatively, the photonic chip is used to receive optical signals, and the PCB is used to convert the optical signals into electrical signals and process them.

[0066] Figure 7 is a schematic diagram of an optical system provided in an embodiment of the present application. As shown in Figure 7, the optical system may include an optoelectronic device and an optical module as shown in Figure 6. The optoelectronic device may be any one of an optical switch, a fiber optic router, and a fiber optic network card, and the optoelectronic device is connected to the optical module.

[0067] Optoelectronic devices can include multiple ports, each corresponding to an optical transmission channel. These ports are connected to optical modules, enabling multi-channel, high-speed data transmission. Optical switches can be used to exchange data between multiple optical transmission channels. Fiber optic routers can convert optical signals into data signals and forward and route these signals. Fiber optic network cards can be used in Ethernet networks to connect computers to optical fibers.

[0068] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A packaging structure, characterized in that: It includes a photonic chip, an optical fiber array and a substrate, wherein: The photonic chip is provided with a pattern spot converter, which is composed of a cantilever beam waveguide and a first groove, wherein there is a gap between the cantilever beam waveguide and the first groove; The optical fiber array comprises optical fibers, a bottom plate and a cover plate, the bottom plate comprises a second groove, the second groove is used to accommodate the optical fibers, and the cover plate is buckled with the bottom plate; The photonic chip is arranged on the upper surface of the substrate, and the bottom plate or the cover plate is arranged on the upper surface of the substrate, and the cantilever beam waveguide is coupled and connected with the optical fiber.

2. The packaging structure according to claim 1, characterized in that: The coupling connection between the cantilever beam waveguide and the optical fiber includes: a terminal end of the cantilever beam waveguide is butted with a terminal end of the optical fiber.

3. The packaging structure according to claim 1 or 2, characterized in that: Projections of the optical fiber and the photonic chip on the substrate do not overlap.

4. The packaging structure according to any one of claims 1 to 3, characterized in that: in: The bottom plate and the projection of the photonic chip on the substrate have a distance therebetween, and the optical fiber extends out of the bottom plate at one end adjacent to the photonic chip; or The projections of the cover plate and the photonic chip on the substrate are spaced apart, and the optical fiber extends out of the cover plate at one end adjacent to the photonic chip; or The bottom plate and the projection of the photonic chip on the substrate have a spacing, and the cover plate and the projection of the photonic chip on the substrate have a spacing, and the optical fiber extends beyond the bottom plate and the cover plate at one end adjacent to the photonic chip.

5. The packaging structure according to any one of claims 1 to 4, characterized in that: in: The material of the substrate is fused quartz, Invar alloy, Kovar alloy, silicon carbide, silicon, aluminum oxide, aluminum nitride or tungsten copper alloy; and / or The thermal expansion coefficient of the substrate is 0.3-10 ppm / °C.

6. The packaging structure according to any one of claims 1 to 5, characterized in that: A first bonding portion is provided at the coupling point between the cantilever beam waveguide and the optical fiber, wherein: The first bonding portion is made of silicone; and / or The modulus of the first bonding portion is less than 1 MPa; and / or The refractive index of the first bonding portion is 1.35-1.45; and / or The thermal expansion coefficient of the first bonding portion is less than 100 ppm / °C.

7. The packaging structure according to any one of claims 1 to 6, characterized in that: A second bonding portion is disposed in the first groove, the second bonding portion is in contact with the cantilever beam waveguide, or the second bonding portion covers the cantilever beam waveguide, wherein: The second bonding portion is made of silicone; and / or The modulus of the second bonding portion is less than 1 MPa; and / or The refractive index of the second bonding portion is 1.35-1.45; and / or The thermal expansion coefficient of the second bonding portion is less than 100 ppm / °C.

8. The packaging structure according to any one of claims 1 to 7, characterized in that: An adhesive layer is provided between the optical fiber array and / or the photonic chip and the substrate, wherein: The adhesive layer is made of epoxy resin or acrylic acid; and / or The shrinkage rate of the adhesive layer is less than 0.3%.

9. The packaging structure according to any one of claims 1 to 8, characterized in that: The substrate is provided with a glue guiding groove, and the glue guiding groove is located between the photonic chip and the optical fiber array.

10. The packaging structure according to any one of claims 1 to 9, characterized in that: The pattern spot converter includes N cantilever beam waveguides, the optical fiber array includes N optical fibers, the N cantilever beam waveguides correspond to the N optical fibers one by one, the cantilever beam waveguides in the N cantilever beam waveguides are coupled with the corresponding optical fibers, and N is a positive integer.

11. The packaging structure according to any one of claims 1 to 10, characterized in that: in: The packaging structure includes M optical fiber arrays, the photonic chip includes M mode spot converters, the M optical fiber arrays and the The M spot mode converters correspond one to one, and the optical fiber arrays in the M optical fiber arrays are coupled with the corresponding spot mode converters, and M is a positive integer.

12. An optical module, characterized in that: It comprises a packaging structure as claimed in any one of claims 1 to 11 and an optical component, wherein the optical component is optically connected to the packaging structure, and the optical component is used to receive and / or send an optical signal.

13. An optical system, characterized in that: It comprises an optoelectronic device and the optical module as claimed in claim 12, wherein the optoelectronic device is connected to the optical module, and the optoelectronic device is any one of an optical switch, an optical fiber router, and an optical fiber network card.

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