Packaging structure, optical module and optical system

Abstract

Provided in the present application are a packaging structure, an optical module and an optical system. The packaging structure comprises an optical fiber unit and a chip unit, wherein the chip unit comprises a photonics chip and a chip cover plate, the photonics chip being snap-fitted with the chip cover plate, a spot size converter is provided in the photonics chip, and the spot size converter is composed of a cantilevered waveguide and a first recess; the optical fiber unit comprises an optical fiber, a bottom plate and an optical fiber cover plate; and the waveguide is coupled to the optical fiber, wherein a first bonding portion is provided between the chip cover plate and the bottom plate, and a second bonding portion is provided between the photonics chip and the optical fiber cover plate; or a first bonding portion is provided between the chip cover plate and the optical fiber cover plate, and a second bonding portion is provided between the photonics chip and the bottom plate. In the packaging structure, the chip cover plate is arranged on the photonics chip to form the chip unit, such that a bonding area between the chip unit and an optical fiber array is increased, the mechanical stability of the packaging structure is improved, and the alignment between the waveguide of the photonics chip and the optical fiber of the optical fiber array is realized.

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 202311447177.1, 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 the mode field diameter of standard optical fibers, direct coupling of the waveguides to the optical fibers results in significant coupling losses. Currently, photonic chip and optical fiber packaging structures can be categorized into end-face coupled and grating coupled packaging. As an end-face coupled packaging approach, 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 spot size with the optical fiber's spot size. The spot size converter can be a cantilever beam. The bottom of the cantilever beam is etched to form a first groove, leaving the waveguide suspended relative to the groove, forming a cantilever waveguide. The air in the first groove confines the transmitted optical signal to the cantilever waveguide, achieving mode field matching and reducing packaging losses. The packaging method for cantilever beam spot size converters is end-face bonding coupling. However, cantilever beam structures are stress-sensitive. For example, changes in ambient temperature, external forces, and movement of the packaging structure can all cause stress to act on the cantilever waveguide, altering its optical transmission characteristics. High stress can even damage the waveguide's mechanical structure. Furthermore, directly packaging the photonic chip and fiber array can easily cause the fiber to shift, resulting in poor mechanical reliability.

[0005] Therefore, in the end-face coupled packaging structure including the cantilever beam type spot converter, how to achieve stress balance of the cantilever beam structure and ensure that the optical fiber is not easily displaced is an urgent problem to be solved.

[0006] Summary of the Invention

[0007] The present application provides a packaging structure, an optical module, and an optical system. By arranging a chip cover on a photonic chip to form a chip unit, the bonding area between the chip unit and the optical fiber array is increased, the mechanical stability of the packaging structure is increased, and the stress balance of the cantilever beam waveguide is achieved.

[0008] In a first aspect, a packaging structure is provided, comprising a chip unit and an optical fiber unit, wherein: the chip unit comprises a photonic chip and a chip cover plate, the photonic chip and the chip cover plate being fastened together, a spot mode converter being provided in the photonic chip, the spot mode converter being composed of a cantilever beam waveguide and a first groove, wherein a gap is provided between the cantilever beam waveguide and the first groove; the optical fiber unit comprises an optical fiber, a base plate, and an optical fiber cover plate, the base plate being provided with a second groove for accommodating the optical fiber, the optical fiber cover plate being fastened together with the base plate; the cantilever beam waveguide being coupled to the optical fiber; a first bonding portion being provided between the chip cover plate and the base plate, and a second bonding portion being provided between the photonic chip and the optical fiber cover plate; or a first bonding portion being provided between the chip cover plate and the optical fiber cover plate, and a second bonding portion being provided between the photonic chip and the base plate. In the packaging structure, by providing the chip cover plate on the photonic chip, the bonding area between the chip unit and the optical fiber array is increased, the mechanical stability of the packaging structure is enhanced, the optical fiber position shifting or even falling off caused by ambient temperature changes is improved, and alignment of the cantilever beam waveguide with the optical fiber is achieved. In addition, the addition of the chip cover plate can also balance the stress above and below the first groove position near the first bonding portion, so as to achieve low-stress packaging of the cantilever beam waveguide.

[0009] In conjunction with the first aspect, in certain implementations of the first aspect, the bottom of the optical fiber unit is suspended, and the coupling connection between the cantilever beam waveguide and the optical fiber includes: the end of the cantilever beam waveguide is butted against the end of the optical fiber. Thus, by directly butting the waveguide in the chip unit with the optical fiber in the optical fiber unit, the transmission distance of the optical signal can be shortened and packaging loss can be reduced. Furthermore, the provision of the chip cover increases the bonding area between the chip unit and the optical fiber unit. Even if the bottom of the optical fiber unit is suspended for precise alignment of the waveguide and optical fiber, the mechanical stability of the packaging structure can be maintained.

[0010] In combination with the first aspect, in certain implementations of the first aspect, the projection of the optical fiber and the projection of the photonic chip have an overlapping portion on the plane where the bottom of the photonic chip is located, and the projection of the optical fiber cover plate or the bottom plate with a first adhesive portion provided between the chip cover plate at least partially covers the overlapping portion. That is, the optical fiber and the bottom plate or the optical fiber cover plate extend together to the photonic chip. During the chip preparation process, in order to separate the chips from each other, it is necessary to cut the chips with a knife or a laser. Therefore, during the waveguide etching, the waveguide will be retracted to avoid damage to the waveguide end face caused by cutting. By extending the optical fiber to the photonic chip, the transmission loss of the optical signal can be reduced and the coupling efficiency can be optimized. In addition, since the optical fiber cover plate or the bottom plate also extends to the photonic chip, the contact area between the chip unit and the optical fiber unit is guaranteed to be constant, thereby increasing the mechanical stability of the packaging structure.

[0011] In combination with the first aspect, in certain implementations of the first aspect, wherein: on the plane where the bottom of the photonic chip is located, the projection of the optical fiber and the projection of the photonic chip have an overlapping portion, and the projection of the chip cover at least partially covers the overlapping portion; wherein the chip cover has a cut angle, and the cut angle is used to avoid the optical fiber. During the chip preparation process, in order to separate the chips from each other, it is necessary to cut the chips with a knife or laser. Therefore, during waveguide etching, the waveguide will be retracted to avoid damage to the waveguide end face caused by cutting. By extending the optical fiber above the photonic chip, the transmission loss of the optical signal can be reduced and the coupling efficiency can be optimized. In addition, in order to ensure that the contact area between the chip unit and the optical fiber unit is constant and does not affect the transmission of the optical signal, it is necessary to set a cut angle on the chip cover.

[0012] In conjunction with the first aspect, in certain implementations of the first aspect, the first adhesive portion and / or the second adhesive portion are made of epoxy resin or acrylic resin, and / or the shrinkage rate of the first adhesive portion and / or the second adhesive portion is less than 0.3%. This prevents displacement between the chip unit and the optical fiber unit, ensures precise alignment between the waveguide and the optical fiber, reduces packaging loss, ensures a stable connection between the chip unit and the optical fiber unit, and increases the mechanical stability of the packaging structure.

[0013] In conjunction with the first aspect, in certain implementations of the first aspect, the photonic chip includes N cantilever waveguides, the optical fiber unit includes N optical fibers, the N cantilever waveguides correspond one-to-one to the N optical fibers, and each of the N cantilever waveguides is coupled to its corresponding optical fiber, 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 adding a chip cover, the bonding area between the chip unit and the optical fiber unit is increased, the stability of the package structure is enhanced, and precise alignment of multiple waveguides with multiple optical fibers is achieved.

[0014] In conjunction with the first aspect, in certain implementations of the first aspect, the packaging structure includes M optical fiber units, the photonic chip includes M spot mode converters, the M optical fiber units correspond to the M spot mode converters one-to-one, and the optical fiber units in the M optical fiber units 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. 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.

[0015] 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.

[0016] 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

[0017] FIG1 is a schematic diagram of a packaging structure provided in an embodiment of the present application.

[0018] FIG2 is a schematic diagram of a pattern spot converter provided in an embodiment of the present application.

[0019] FIG3 is a schematic diagram of another packaging structure provided in an embodiment of the present application.

[0020] FIG4 is a schematic diagram of another packaging structure provided in an embodiment of the present application.

[0021] FIG5 is a schematic diagram of an optical module provided in an embodiment of the present application.

[0022] FIG6 is a schematic diagram of an optical system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The technical solution in this application will be described below with reference to the accompanying drawings.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] The packaging of photonic integrated circuits (PICs) and fiber arrays (FAs) is one of the key technical difficulties 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 of 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 connecting the end face of the photonic chip and 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 easy assembly, the grating itself will produce optical signal loss. The end-face coupled packaging structure has become the main form of coupling packaging structure due to its advantages such as low packaging loss and small size.

[0031] As a packaging method with an end-face coupling structure, a spot size converter (SSC) can be installed at the edge of the photonic chip, or at 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, forming a cantilever waveguide. The air in the first groove confines the transmitted optical signal to the cantilever waveguide, thereby achieving mode field matching and reducing packaging losses. The packaging method using a cantilever beam spot converter is end-face bonding coupling. However, the cantilever beam structure is stress-sensitive. For example, changes in ambient temperature, application of external forces, and movement of the packaging structure can all cause stress to act on the cantilever waveguide, which can cause changes in the optical transmission characteristics of the cantilever waveguide. High stress can also damage the waveguide's mechanical structure. In addition, directly packaging the photonic chip and optical fiber array can easily cause the optical fiber to shift, resulting in poor packaging mechanical reliability.

[0032] Therefore, in the end-face coupled packaging structure including the cantilever beam type spot converter, how to achieve stress balance of the cantilever beam structure and ensure that the optical fiber is not easily displaced is an urgent problem to be solved.

[0033] In view of this, the embodiments of the present application provide a packaging structure, an optical module and an optical system, which form a chip unit by setting a chip cover on the photonic chip, increase the bonding area between the chip unit and the optical fiber array, increase the mechanical stability of the packaging structure, and achieve stress balance of the cantilever beam waveguide.

[0034] Figure 1 is a schematic diagram of a packaging structure provided by an embodiment of the present application. Figure 1 (a) and (b) show side views of the packaging structure, and Figure 1 (c) shows a top view of the packaging structure. As shown in Figure 1, the packaging structure may include a chip unit and an optical fiber unit. The chip unit includes a photonic chip 111 and a chip cover plate 112, and the photonic chip 111 is fastened to the chip cover plate 112, and the fastening method may be glue bonding or other methods. A pattern spot converter is provided in the photonic chip, and the pattern spot converter is composed of a cantilever beam waveguide 114 and a first groove 115, wherein the cantilever beam waveguide 114 is not in contact with the first groove 115.

[0035] The cantilever waveguide 114 may specifically refer to the portion of the waveguide 113 that is suspended relative to the first groove 115. Alternatively, the cantilever waveguide 114 and the waveguide 113 may be separate optical components, with an optical element such as a coupler or beam splitter disposed therebetween. This application is not limited thereto. A gap may exist between the cantilever waveguide 114 and the first groove 115, or alternatively, the cantilever waveguide 114 and the first groove 115 may be spaced apart or not in contact with each other. Furthermore, the first groove may also be referred to as an undercut.

[0036] The fiber optic unit includes a base plate 121, a fiber optic cover plate 122, and optical fibers 123. A second groove, which may be a V-groove, is provided in the base plate 121 to accommodate the optical fibers. The fiber optic cover plate 122 snaps into place with the base plate 121, either by gluing or other methods. The fiber optic unit may also be referred to as a fiber array.

[0037] The cantilever beam waveguide 114 is coupled to the optical fiber 123. The coupling between the cantilever beam waveguide 114 and the optical fiber 123 may specifically refer to a direct optical connection or an indirect optical connection between the cantilever beam waveguide 114 and the optical fiber 123. The indirect optical connection may refer to an adapter, a lens, a polymer waveguide, etc. being provided between the cantilever beam waveguide 114 and the optical fiber 123.

[0038] In some implementations, as shown in FIG. 1( a ), a first bonding portion 130 is provided between the chip cover plate 112 and the optical fiber cover plate 122 , and a second bonding portion 140 is provided between the photonic chip 111 and the base plate 121 .

[0039] In some implementations, as shown in FIG1( b ), a first bonding portion 130 is provided between the chip cover plate 112 and the base plate 121 , and a second bonding portion 140 is provided between the photonic chip 111 and the optical fiber cover plate 122 .

[0040] In the packaging structure shown in Figure 1, a chip cover is provided on the photonic chip to increase the bonding area between the chip unit and the optical fiber unit, thereby increasing the mechanical stability of the packaging structure, improving the positional movement or even detachment of the optical fiber caused by changes in ambient temperature, and achieving alignment between the waveguide in the photonic chip and the optical fiber in the optical fiber array. In addition, the addition of the chip cover can also balance the stress above and below the first groove position near the first bonding portion, thereby achieving low-stress packaging of the cantilever beam waveguide. The chip cover can be a square cover or a special-shaped cover, which is not limited in this application.

[0041] In some implementations, as shown in Figure 1 , the bottom of the optical fiber unit is suspended in the air, and the coupling connection between the cantilever beam waveguide 114 and the optical fiber 123 includes: the end of the cantilever beam waveguide 114 is butted against the end of the optical fiber 123. This reduces the number of coupling components, shortens the transmission distance of the optical signal, and reduces packaging losses. Furthermore, the provision of the chip cover increases the bonding area between the chip unit and the optical fiber unit. Even if the bottom of the optical fiber unit is suspended in the air to ensure precise alignment of the waveguide and optical fiber, the mechanical stability of the packaging structure is maintained.

[0042] In some implementations, the total area of ​​the first adhesive portion 130 and the second adhesive portion 140 is greater than 1.5 mm 2 , thereby ensuring that the bonding area between the chip unit and the optical fiber array is increased and the mechanical stability of the packaging structure is increased. Among them, the area of ​​the first bonding portion 130 can be greater than 0.75mm 2 The area of ​​the second bonding portion 140 may be larger than 0.75 mm 2 .

[0043] In some implementations, the shrinkage rate of the first adhesive portion 130 and / or the second adhesive portion 140 can be less than 0.3%, thereby preventing displacement between the chip unit and the optical fiber array unit, ensuring precise alignment between the waveguide and the optical fiber, and reducing packaging loss. The first adhesive portion 130 and / or the second adhesive portion 140 can be made of epoxy resin or acrylic resin, thereby preventing displacement between the chip unit and the optical fiber unit, ensuring precise alignment between the waveguide and the optical fiber, reducing packaging loss, and ensuring a stable connection between the chip unit and the optical fiber unit, thereby increasing the mechanical stability of the packaging structure. The first adhesive portion 130 and the second adhesive portion 140 can be formed together by a glue during the packaging process, or can be formed separately by multiple bonding processes. The first adhesive portion 130 and the second adhesive portion 140 can be made of the same material or different materials, and this application does not impose any restrictions on this.

[0044] In some implementations, due to the provision of the first adhesive portion, the corresponding adhesive material will fill the first groove 115. That is, a third adhesive portion is provided in the first groove 115. The third adhesive portion can be made of epoxy resin or acrylic. The third adhesive portion can contact the cantilever waveguide 114, or the third adhesive portion can cover the cantilever waveguide 114. The thickness of the third adhesive portion below the cantilever waveguide 114 can be the same as the thickness of the third adhesive portion above the cantilever waveguide 114, thereby further ensuring stress balance in the cantilever waveguide.

[0045] In some implementations, the photonic chip includes N cantilever waveguides, the optical fiber unit includes N optical fibers, the N cantilever waveguides correspond one-to-one to the N optical fibers, and each cantilever waveguide in the N cantilever waveguides is coupled to its corresponding optical fiber, 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, adding a chip cover increases the bonding area between the chip unit and the optical fiber unit, improves the stability of the package structure, and achieves precise alignment of multiple cantilever waveguides with multiple optical fibers.

[0046] Figure 2 is a schematic diagram of a spot size converter provided in an embodiment of the present application. The spot size converter comprises a cantilever waveguide 210 and a second groove 220, with the cantilever waveguide 210 not in contact with the second groove 220. The second groove 220 in the spot size converter, also known as an undercut, can be formed by etching the bottom of the photonic chip, thereby leaving the cantilever waveguide 210 suspended relative to the second groove 220, forming a cantilevered cantilever waveguide. As shown in Figure 2, the cantilever waveguide can be supported by a support 230. In the spot size converter, the air in the second groove 220 can confine the optical signal transmitted in the package structure to the cantilever waveguide, thereby achieving mode field matching and reducing package loss. In some implementations, other media, such as polymer media, can also be provided in the second groove 220, although this is not a limitation of the present application. In the package structure provided in the embodiment of the present application, the spot size converter can expand the spot size of the cantilever waveguide 210 to 9μm, the same as that of an optical fiber.

[0047] When a spot converter is incorporated into a photonic chip, the cantilever waveguide is sensitive to stress. For example, changes in ambient temperature, external forces, and movement of the packaging structure can all cause stress to act on the cantilever waveguide, altering its optical transmission characteristics. High stress can even damage the waveguide's mechanical structure. By adding a chip cover and increasing the bonding area between the chip and fiber units, the mechanical stability of the package structure can be maintained, reducing stress changes near the cantilever waveguide caused by temperature fluctuations, displacement, and external forces, thereby achieving low-stress packaging.

[0048] When the photonic chip includes a cantilever beam waveguide, it is difficult to use grinding and polishing to ensure that the end faces of the chip cover and the photonic chip are aligned because the cantilever beam waveguide is relatively fragile. At this time, a precision fixture can be used to fix the relative position of the chip cover and the photonic chip so that the chip cover can be snapped together with the photonic chip.

[0049] In some implementations, the pattern spot converter includes N cantilever beam waveguides. In this case, the lateral dimension of the second groove 220 can be extended accordingly, and the bracket 230 is used to support the N cantilever beam waveguides. The optical fiber unit includes N optical fibers, corresponding one to one to the N cantilever beam waveguides of the pattern spot converter. The waveguides in the N cantilever beam waveguides are coupled to the corresponding optical fibers. In the case of a multi-channel packaging structure, by adding a chip cover plate, the bonding area between the chip unit and the optical fiber unit is increased, and the stress changes near the waveguide caused by temperature changes, displacement, external force application, etc. in the packaging structure are reduced, thereby achieving low-stress packaging, increasing the stability of the packaging structure, reducing packaging losses, and achieving precise alignment of multiple waveguides and multiple optical fibers. 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 a transmission medium for optical signals to achieve a high-density lateral pitch arrangement scheme without using a conventional 250μm-sized optical fiber.

[0050] FIG3 is a schematic diagram of another packaging structure provided by an embodiment of the present application. The chip unit and fiber unit in FIG3 are similar to those in FIG1 and are not further described herein. The chip unit includes a photonic chip 311, a chip cover plate 312, a waveguide 313, a cantilever beam waveguide 314, and a first groove 315, and the patterned fiber unit includes a base plate 321, a fiber cover plate 322, and an optical fiber 323.

[0051] In some implementations, as shown in FIG3(a), on the plane where the bottom of the photonic chip 311 is located, the projection of the optical fiber 323 overlaps with the projection of the photonic chip 311, and the projection of the base plate 321 at least partially covers the overlapping portion. That is, the optical fiber 323 and the base plate 321 extend together to the photonic chip 311. During the chip preparation process, in order to separate the chips from each other, it is necessary to cut the chips with a knife or laser. Therefore, during waveguide etching, the waveguide will be retracted to avoid damage to the waveguide end face caused by cutting. By extending the optical fiber to the photonic chip, the transmission distance of the optical signal can be shortened and the coupling efficiency can be optimized. In addition, since the base plate also extends to the photonic chip, the contact area between the chip unit and the optical fiber unit is guaranteed to be constant, thereby increasing the mechanical stability of the packaging structure. In addition, FIG3(a) only shows the case where the base plate 321 is extended to the photonic chip 311. When the first bonding portion is provided between the chip cover plate and the fiber cover plate, the projection of the optical fiber overlaps with the projection of the photonic chip, and the projection of the fiber cover plate at least partially covers the overlapping portion. In other words, the optical fiber and the fiber cover plate extend together onto the photonic chip.

[0052] In some implementations, as shown in FIG3(b), on the plane where the bottom of the photonic chip 311 is located, the projection of the optical fiber 323 and the projection of the photonic chip 311 have an overlapping portion, and the projection of the chip cover 312 at least partially covers the overlapping portion. The chip cover 312 has a cut angle, and the cut angle is used to avoid the optical fiber 323. During the chip preparation process, in order to separate the chips from each other, it is necessary to cut the chips with a knife or laser. Therefore, during the waveguide etching, the waveguide will be retracted to avoid damage to the waveguide end face caused by cutting. By extending the optical fiber above the photonic chip, the transmission distance of the optical signal can be shortened and the coupling efficiency can be optimized. In addition, in order to ensure that the contact area between the chip unit and the optical fiber unit is constant and does not affect the transmission of the optical signal, it is necessary to set a cut angle on the chip cover.

[0053] FIG4 is a schematic diagram of another packaging structure provided by an embodiment of the present application. As shown in FIG4 , the packaging structure includes M optical fiber units 420, and the photonic chip includes M spot converters 410. The M optical fiber units 420 correspond one-to-one to the M spot converters 410. The optical fiber units in the M optical fiber units are coupled to the corresponding spot 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-package structure (coupled package optics, CPO), thereby shortening the transmission distance of the optical signal, reducing packaging loss, and reducing system cost and energy loss. It should be understood that FIG4 only illustrates the case where M is equal to 4, and should not limit the specific form of the packaging structure.

[0054] In some implementations, the optical fiber unit in the M optical fiber units includes an optical fiber, and the spot mode converter in the M spot mode converters includes a cantilever beam waveguide. In this case, the optical fiber unit and the spot mode converter are specifically used for single-channel optical signal transmission.

[0055] In some implementations, the optical fiber units in the M optical fiber units 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. The number of optical fibers included in each of the M optical fiber units can be the same or different, and correspondingly, the number of cantilever beam waveguides included in each of the M spot pattern converters can be the same or different. In this case, the optical fiber units and spot pattern converters are specifically configured for multi-channel optical signal transmission.

[0056] Figure 5 is a schematic diagram of an optical module provided in an embodiment of the present application. As shown in Figure 5, the optical module may include an optical component 510 and a packaging structure 520, the optical component 510 is optically connected to the packaging structure 520, and the optical component 510 is used to receive and / or send optical signals. The specific configuration of the packaging structure 520 is shown in Figures 1 to 5. Among them, when the optical component 510 is used to send an optical signal, the optical component 510 may include a light source, a modulator, a filter, etc. When the optical component 510 is used to receive an optical signal, the optical component 510 may include a processor, a detector, etc. In some implementations, the optical component 510 includes light sources of multiple wavelengths, and the corresponding packaging structure 520 is used to send and / or receive optical signals of multiple wavelengths.

[0057] The components of the optical assembly can be provided in the photonic chip in the package structure, or the components of the optical assembly and the photonic chip and optical fiber unit in the package structure can be discrete components. The specific optical module form is determined according to actual conditions. The optical connection between the optical assembly 510 and the package structure 520 can refer to 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 510 and the photonic chip or optical fiber unit in the package structure 520.

[0058] In some implementations, the optical module further includes a printed circuit board (PCB), which is electrically connected to the photonic chip in the package structure 520. The specific electrical connection method can be through wires, wire welding, wire bonding, or through sockets, pin connections, 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 send 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.

[0059] In which case, when the packaging structure is a CPO packaging form as shown in FIG4 , the optical module can also be called an optical engine.

[0060] Figure 6 is a schematic diagram of an optical system provided in an embodiment of the present application. As shown in Figure 6, 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.

[0061] 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.

[0062] The above are only specific embodiments of the present application, but the scope of protection of this 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 chip unit and an optical fiber unit, wherein: The chip unit comprises a photonic chip and a chip cover plate, wherein the photonic chip is buckled with the chip cover plate, and a pattern spot converter is arranged in the photonic chip, wherein the pattern spot converter is composed of a cantilever beam waveguide and a first groove, wherein a gap is provided between the cantilever beam waveguide and the first groove; The optical fiber unit comprises an optical fiber, a bottom plate and an optical fiber cover plate, wherein a second groove is provided in the bottom plate, the second groove is used to accommodate the optical fiber, and the optical fiber cover plate is buckled with the bottom plate; Wherein, the cantilever beam waveguide is coupled and connected with the optical fiber; Wherein, a first bonding portion is provided between the chip cover plate and the base plate, and a second bonding portion is provided between the photonic chip and the optical fiber cover plate; or A first bonding portion is provided between the chip cover plate and the optical fiber cover plate, and a second bonding portion is provided between the photonic chip and the base plate.

2. The packaging structure according to claim 1, characterized in that: The bottom of the optical fiber unit is suspended in the air, and the coupling connection between the cantilever beam waveguide and the optical fiber includes: the end of the cantilever beam waveguide is butted against the end of the optical fiber.

3. The packaging structure according to claim 1 or 2, characterized in that: in: On the plane where the bottom of the photonic chip is located, the projection of the optical fiber and the projection of the photonic chip have an overlapping part, and the projection of the optical fiber cover plate or the bottom plate having a first adhesive portion arranged between the chip cover plate at least partially covers the overlapping part.

4. The packaging structure according to claim 1 or 2, characterized in that: in: On the plane where the bottom of the photonic chip is located, the projection of the optical fiber and the projection of the photonic chip have an overlapping portion, and the projection of the chip cover at least partially covers the overlapping portion; Wherein, the chip cover plate has a cut corner, and the cut corner is used to avoid the optical fiber.

5. The packaging structure according to any one of claims 1 to 4, characterized in that: in: The first adhesive portion and / or the second adhesive portion are made of epoxy resin or acrylic acid; and / or The shrinkage rate of the first adhesive portion and / or the second adhesive portion is less than 0.3%.

6. The packaging structure according to any one of claims 1 to 5, characterized in that: The pattern spot converter includes N cantilever beam waveguides, the optical fiber unit 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.

7. The packaging structure according to any one of claims 1 to 6, characterized in that: in: The packaging structure includes M optical fiber units, the photonic chip includes M spot converters, the M optical fiber units correspond to the M spot converters one by one, the optical fiber units in the M optical fiber units are coupled with the corresponding spot converters, and M is a positive integer.

8. An optical module, characterized in that: It comprises a packaging structure as claimed in any one of claims 1 to 7 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 optical signals.

9. An optical system, characterized in that: It comprises an optoelectronic device and the optical module as claimed in claim 8, 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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