Packaging structure

Abstract

The embodiment of the present disclosure provides a packaging structure. The packaging structure comprises: a substrate; an optical chip and a coupler located on the substrate; a light-transmitting medium layer in contact with an output end and / or an input end of the optical chip and in contact with the coupler; wherein the light-transmitting medium layer comprises a first waveguide structure formed in the light-transmitting medium layer by a laser direct writing waveguide technology; the first waveguide structure is used for limiting a transmission path of an optical signal in the light-transmitting medium layer; and the coupler is used for realizing optical coupling between the first waveguide structure and an optical fiber.

Description

Technical Field

[0001] This disclosure relates to the field of electronic packaging technology, and more particularly to a packaging structure. Background Technology

[0002] With the explosive growth of artificial intelligence, high-performance computing, and data center traffic, traditional electrical interconnects are facing severe bottlenecks in terms of bandwidth density and power consumption. To overcome this challenge, optoelectronic co-packaging technology tightly integrates optical chips and electrical chips (such as specific computing units like switching chips) within a package. By replacing some electrical interconnects with optical interconnects, it significantly shortens the transmission path of high-speed signals, reduces system power consumption, and achieves higher interconnect bandwidth.

[0003] In optoelectronic co-packaging architecture, optical chips and electrical chips are integrated through advanced packaging processes to achieve optoelectronic signal conversion and interconnection. However, after the optical signal is led out from the nanowaveguide of the optical chip, it needs to pass through an optical channel composed of encapsulation materials such as underfill adhesive and molding compound before finally reaching the receiving end. During this process, the huge optical loss caused by interface scattering, material absorption and geometric misalignment has become the main technical bottleneck limiting link performance and integration. Utility Model Content

[0004] In view of this, the present disclosure provides a packaging structure.

[0005] To achieve the above objectives, the technical solution disclosed herein is implemented as follows: This disclosure provides a packaging structure, which includes: substrate; Optical chip and coupler located on the substrate; A light-transmitting dielectric layer that contacts the output and / or input terminals of the optical chip and the coupler; wherein the light-transmitting dielectric layer includes a first waveguide structure formed within the light-transmitting dielectric layer using laser direct-write waveguide technology; the first waveguide structure is used to limit the transmission path of the optical signal within the light-transmitting dielectric layer; the coupler is used to realize optical coupling between the first waveguide structure and the optical fiber.

[0006] In some embodiments, the packaging structure further includes: An electrical chip located on the substrate and electrically connected to the optical chip, the electrical chip being used to provide electrical drive signals to the optical chip and / or process the electrical signals transmitted by the optical chip.

[0007] In some embodiments, the area of ​​the electrical chip is smaller than the area of ​​the optical chip.

[0008] In some embodiments, the electrical chip is located on the optical chip and is electrically connected to the optical chip by bonding. The optical chip has a connection structure that extends through it along a first direction perpendicular to the surface of the substrate; the electrical chip is connected to the substrate through the connection structure.

[0009] In some embodiments, the output / input end of the optical chip is located on the first surface in contact with the electrical chip; the optical chip has a second waveguide structure for transmitting optical signals extending along a second direction parallel to the surface of the substrate, and a reflector disposed in an optical path optically connected to the second waveguide structure for changing the transmission direction of the output / input optical signals of the second waveguide structure; The optical signal output from the second waveguide structure is coupled to the first waveguide structure via the mirror; or the optical signal output from the first waveguide structure is coupled to the second waveguide structure via the mirror.

[0010] In some embodiments, the output / input terminal of the optical chip is located on the side of the optical chip; the optical chip has a second waveguide structure for conducting optical signals extending along a second direction parallel to the surface of the substrate; The optical signal output from the second waveguide structure is coupled to the first waveguide structure; or the optical signal output from the first waveguide structure is coupled to the second waveguide structure.

[0011] In some embodiments, the optical chip includes at least two second waveguide structures extending along the second direction and spaced apart along the first direction; the at least two second waveguide structures together constitute an optical signal transmission channel inside the optical chip.

[0012] In some embodiments, the refractive index at the first waveguide structure in the light-transmitting medium layer is greater than the refractive index at the remaining locations in the light-transmitting medium layer.

[0013] In some embodiments, the material of the light-transmitting medium layer includes silicon oxide or aluminum oxide.

[0014] In some embodiments, the cross-section of the first waveguide structure perpendicular to the optical transmission direction is circular, elliptical, or rectangular.

[0015] This embodiment of the present disclosure sets up a light-transmitting medium layer between the optical chip and the coupler, and uses laser direct-write waveguide technology to form a first waveguide structure in the light-transmitting medium layer, thereby restricting the transmission path of the optical signal in the light-transmitting medium layer, thereby reducing optical loss during transmission and improving the overall optical transmission efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a photoelectric co-encapsulation structure provided in an example; Figure 2 A schematic diagram of a photoelectric co-encapsulation structure provided in another example; Figure 3 This is a schematic diagram of a packaging structure provided in an embodiment of the present disclosure; Figure 4 This is a schematic diagram of another packaging structure provided in an embodiment of the present disclosure; Figure 5 A flowchart illustrating a method for manufacturing a packaging structure according to an embodiment of this disclosure; Figures 6 to 10 This diagram illustrates the steps of a method for manufacturing a packaging structure according to an embodiment of the present disclosure. Detailed Implementation

[0017] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0018] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of this disclosure. However, it will be apparent to those skilled in the art that this disclosure may be practiced without one or more of these details. In other instances, to avoid confusion with this disclosure, certain technical features well-known in the art have not been described; that is, not all features of actual embodiments are described herein, nor are well-known functions and structures described in detail.

[0019] In the accompanying drawings, for clarity, the dimensions of layers, areas, and elements, as well as their relative dimensions, may be exaggerated. The same reference numerals denote the same elements throughout.

[0020] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this disclosure, the first element, component, area, layer, or portion discussed below may be referred to as a second element, component, area, layer, or portion. And the discussion of a second element, component, area, layer, or portion does not imply that the first element, component, area, layer, or portion necessarily exists in this disclosure.

[0021] Spatial relation terms such as “below,” “under,” “below,” “below,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0022] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprise” and / or “comprising,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0023] To fully understand this disclosure, detailed steps and structures will be presented in the following description to illustrate the technical solutions of this disclosure. Preferred embodiments of this disclosure are described in detail below; however, other embodiments may also be implemented in addition to these detailed descriptions.

[0024] In some examples, optical signals in the optoelectronic co-package structure are freely transmitted through the medium 103 filled between the optical chip 101 and the coupler 102, such as... Figure 1 and Figure 2 As shown. Because medium 103 lacks effective constraint on the optical path, the optical signal is prone to scattering during transmission, resulting in significant optical loss, which in turn affects the overall system performance and stability.

[0025] To address the aforementioned issues, this disclosure proposes a packaging structure. By forming a first waveguide structure within a transparent dielectric layer located between the optical chip and the coupler using laser direct-write waveguide technology, the propagation path of the optical signal is effectively limited, scattering loss is reduced, and optical signal transmission efficiency is improved. Furthermore, the packaging structure in this disclosure is compatible with existing 3D packaging processes and will not affect the high-speed collaborative operation of the optical chip and the electrical chip, exhibiting good versatility and scalability.

[0026] This disclosure provides a packaging structure, such as Figure 3 As shown, the packaging structure 300 includes: a substrate 301; an optical chip 302 and a coupler 303 located on the substrate 301; a light-transmitting dielectric layer 304 in contact with the output and / or input terminals of the optical chip 302 and in contact with the coupler 303; wherein, the light-transmitting dielectric layer 304 includes a first waveguide structure 305 formed within the light-transmitting dielectric layer 304 using laser direct-write waveguide technology; the first waveguide structure 305 is used to limit the transmission path of the optical signal within the light-transmitting dielectric layer 304; the coupler 303 is used to connect the first waveguide structure 305 to the optical fiber (… Figure 3 Optical coupling between (not shown in the image).

[0027] Here, substrate 301 refers to the support platform used to support the entire packaging structure 300. It is usually made of materials such as silicon, glass or ceramic and has good thermal stability and mechanical strength.

[0028] In some embodiments, substrate 301 serves not only as a mounting platform for devices but also as an integrated wiring layer to achieve electrical connection functions. For example, substrate 301 can be a silicon substrate with multiple through-silicon vias (TSVs) on its surface, which are used to connect circuit structures on upper and lower layers. Alternatively, substrate 301 can be a glass substrate, which provides a more stable optical environment.

[0029] The optical chip 302, or Photonic Integrated Circuit (PIC), is used to generate, process, and output optical signals.

[0030] In some embodiments, the optical chip 302 includes active devices, passive devices, and dynamically tunable devices. The active devices include lasers, modulators, photodetectors, etc., for generating, modulating, and receiving optical signals. The passive devices include waveguides, couplers, filters, etc., for guiding and routing optical signals. The dynamically tunable devices include electro-optic tuners, etc., for achieving flexible signal manipulation.

[0031] Coupler 303 is a key interface device for interconnecting optical chip 302 with external optical fiber. It is used to solve the mode field mismatch problem between the first waveguide structure 305 and the optical fiber, thereby realizing efficient transmission of optical signals.

[0032] In some embodiments, coupler 303 includes an edge coupler and a grating coupler. The edge coupler expands the light spot through a tapered waveguide structure on its end face, offering advantages such as wide bandwidth and high efficiency, but it relies on complex, precise end face alignment. The grating coupler utilizes a periodic surface structure to diffract the beam, supporting wafer-level testing and convenient packaging, but it has a narrower bandwidth and is wavelength-sensitive.

[0033] The light-transmitting dielectric layer 304 is a dielectric layer made of light-transmitting material, covering the output end and / or input end of the optical chip 302, and is used to support, protect and transmit optical signals.

[0034] In some embodiments, the light-transmitting material of the light-transmitting dielectric layer 304 includes silicon oxide (SiO2), aluminum oxide (Al2O3), etc. Materials such as silicon oxide (SiO2) and aluminum oxide (Al2O3) have the characteristics of low light loss and are suitable for high-performance optical packaging.

[0035] Laser-written waveguide technology is a process that locally alters the refractive index of a light-transmitting dielectric layer 304 by irradiating it with a laser. This technology can form a first waveguide structure 305 within a designated area of ​​the light-transmitting dielectric layer 304, guiding the propagation of optical signals, without introducing high temperatures. Specifically, a femtosecond laser can be used to scan a specific area within the light-transmitting dielectric layer 304, causing a change in the refractive index of that area. This forms a weak waveguide structure (i.e., the first waveguide structure 305) to confine the propagation of the optical signal along a specific path, thereby reducing scattering losses.

[0036] The first waveguide structure 305 can have a cylindrical or strip-shaped form. Specifically, the cross-section of the first waveguide structure 105 along the direction perpendicular to the light transmission direction is circular, elliptical, or rectangular.

[0037] The refractive index of the first waveguide structure 305 is slightly higher than that of the surrounding light-transmitting material, enabling the first waveguide structure 305 to guide the light signal to propagate along a set path.

[0038] In some embodiments, the first waveguide structure 305 can be a single-mode waveguide to support single-mode optical signal transmission, which is suitable for high-speed communication scenarios.

[0039] In this embodiment, the two opposite ends of the light-transmitting dielectric layer 304 are in contact with the input and / or output ends of the optical chip 302 and the coupler 303, respectively, to achieve continuous optical signal transmission from the optical chip 302 to the coupler 303. The input end of the optical chip 302 can be a laser source or a modulator, and the output end is an optical signal transmission port. The coupler 303 can be used to guide the optical signal from the first waveguide structure 305 into an optical fiber or other external optical path system.

[0040] In this embodiment, the position of the first waveguide structure 305 within the light-transmitting dielectric layer 304 is precisely controlled using laser direct-write waveguide technology. Utilizing the excellent optical properties of the light-transmitting dielectric layer 304 and the directionality and stability of the first waveguide structure 305, signal loss during transmission is effectively reduced, significantly improving transmission efficiency and reliability. Furthermore, the packaging structure 300 in this embodiment is compatible with existing 3D packaging processes and will not affect the high-speed collaborative operation of the optical chip 302 and the electrical chip, exhibiting good versatility and scalability.

[0041] In some embodiments, the packaging structure 300 further includes an electrical chip 306 located on the substrate 301 and electrically connected to the optical chip 302. The electrical chip 306 is used to provide electrical drive signals to the optical chip 302 and / or process the electrical signals transmitted by the optical chip 302, such as... Figure 3 As shown.

[0042] Here, the electrical chip 306 is an electronic integrated circuit (EIC), which is integrated on the same substrate 301 as the optical chip 302 through an electrical connection. It is used to provide the required electrical drive signal to the optical chip 302, or to receive and process the electrical signals output by the optical chip 302.

[0043] In some embodiments, the electrical connection between the electrical chip 306 and the optical chip 302 can be achieved through metal wiring, gold wire bonding, copper pillars, etc., to ensure efficient signal transmission and stable power supply.

[0044] In some embodiments, the electrical chip 306 is located on the optical chip 302 and is electrically connected to the optical chip 302 by bonding; a connection structure 307 is formed in the optical chip 302 in a first direction perpendicular to the surface of the substrate 301 and extends through the optical chip 302; the electrical chip 306 is connected to the substrate 301 through the connection structure 307.

[0045] In this embodiment of the disclosure, the electrical chip 306 can be electrically connected to the optical chip 302 via a die-to-wafer (D2W) bonding method.

[0046] In one example, the electrical chip 306 is bonded to the optical chip 302 via flip chip bonding, such as... Figure 3 As shown. Specifically, in the flip-chip bonding process, the electrical chip 306 and the optical chip 302 are directly aligned and bonded using metal bumps to achieve a high-density, low-resistance electrical connection. Flip-chip bonding can reduce interconnect length, increase signal transmission speed, and is suitable for high-frequency, high-speed optoelectronic applications. Furthermore, flip-chip bonding can also improve package integration and reliability.

[0047] The connection structure 307 refers to the through-silicon via (TSV) disposed inside the optical chip 302, used to transmit electrical signals from the electrical chip 306 to the circuit layer on the substrate 301. Specifically, the output terminal of the electrical chip 306 is connected to the pads on the surface of the optical chip 302 via metal bumps. Using the connection structure 307 in the optical chip 302 as a bridge, the electrical signal can be transmitted from the output terminal of the electrical chip to the circuit layer 301 of the substrate.

[0048] In some embodiments, the material of the connection structure 307 includes conductive materials, such as copper (Cu), aluminum (Al), etc.

[0049] In some embodiments, the connection structure 307 can be formed in the optical chip 302 by processes such as etching and filling.

[0050] In other embodiments, the electrical chip 306 can also be electrically connected to the optical chip 302 via wire bonding.

[0051] In some embodiments, the output / input terminal of the optical chip 302 is located on the first surface 302a where the optical chip 302 contacts the electrical chip 306; the optical chip 302 has a second waveguide structure 308 extending along a second direction parallel to the surface of the substrate 301 for transmitting optical signals, and a reflector 309 disposed in an optical path optically connected to the second waveguide structure 308 for changing the transmission direction of the output / input optical signals of the second waveguide structure 308; wherein the optical signal output from the second waveguide structure 308 is coupled to the first waveguide structure 305 via the reflector 309; or, the optical signal output from the first waveguide structure 305 is coupled to the second waveguide structure 308 via the reflector 309, such as... Figure 3 As shown.

[0052] Here, the first surface 302a is the interface where the optical chip 302 and the electrical chip 306 directly contact each other, and is used to realize optoelectronic interconnection. The first surface 302a can also be understood as the top surface of the optical chip 302.

[0053] In some embodiments, the optical chip 302 includes at least two second waveguide structures 308 extending along a second direction and spaced apart along a first direction. The at least two second waveguide structures 308 together constitute an optical signal transmission channel inside the optical chip 302.

[0054] In some embodiments, the second waveguide structure 308 may be a ridge waveguide, a strip waveguide, or other forms of low-loss waveguide structure.

[0055] The reflector 309 is a component placed in the optical path to change the direction of optical signal propagation.

[0056] In some embodiments, the reflector 309 includes a thin-film reflector, a prism reflector, an integrated waveguide reflector, and a diffractive reflector.

[0057] Figure 3 In this configuration, the extension direction of the first waveguide structure 305 is perpendicular to the extension direction of the second waveguide structure 308. A reflector 309 is located in the optical path between the second waveguide structure 308 and the first waveguide structure 305, and is used to convert the horizontally propagating optical signal output from the second waveguide structure 308 into a vertically propagating optical signal, thereby coupling the optical signal into the first waveguide structure 305; or, to convert the vertically propagating optical signal output from the first waveguide structure 305 into a horizontally propagating optical signal, thereby coupling the optical signal into the second waveguide structure 308.

[0058] It should be noted that since the size of the electrical chip 306 is typically smaller than that of the optical chip 302, a dielectric layer needs to be fabricated on the sidewalls of the electrical chip 306 to form a continuous and dense package, thereby achieving reliable electrical insulation and mechanical protection. In this embodiment, a light-transmitting material is used to fabricate a dielectric layer covering the sidewalls of the electrical chip 306 (i.e., a light-transmitting dielectric layer 304), and a first waveguide structure 305 is formed within the light-transmitting dielectric layer 304, which reduces the transmission loss of the optical signal while achieving electrical insulation and mechanical protection.

[0059] In some embodiments, the output / input terminals of the optical chip 402 are located on the side of the optical chip 402; the optical chip 402 has a second waveguide structure 308 extending along a second direction parallel to the surface of the substrate 301 for conducting optical signals; wherein the optical signal output from the second waveguide structure 308 is directly coupled to the first waveguide structure 305; or, the optical signal output from the first waveguide structure 305 is coupled to the second waveguide structure 308, such as... Figure 4 As shown.

[0060] Here, the second waveguide structure 308 can be based on Figure 3 The descriptions in the text are for reference only and will not be elaborated upon here.

[0061] Figure 4 In the design, both the first waveguide structure 305 and the second waveguide structure 308 extend in a horizontal direction (i.e., parallel to the substrate surface), and are aligned end-to-end in a straight line. The light-transmitting dielectric layer 304 can serve as a buffer layer between the optical chip 302 and the coupler 303 to provide support and prevent contamination of the interface between the output and input ends of the optical chip 302.

[0062] In some embodiments, when the output / input terminal of the optical chip 402 is located on the side of the optical chip 402, the packaging structure 400 may further include an electrical chip 306 located on the substrate 301 and electrically connected to the optical chip 402, such as... Figure 4 As shown. Figure 4 In the middle, the electrical chip 306 is located on the optical chip 402 and is connected to the optical chip 402 by bonding.

[0063] In some other embodiments, when the output / input terminal of the optical chip 402 is located on the side of the optical chip 402, the electrical chip 306 can also be directly mounted on the substrate 301 and be on the same horizontal plane as the optical chip 402 to form a coplanar structure.

[0064] In some embodiments, the refractive index at the first waveguide structure 305 in the light-transmitting dielectric layer 304 is greater than the refractive index at the remaining locations in the light-transmitting dielectric layer 304.

[0065] In this embodiment of the present disclosure, the laser direct-write waveguide technology utilizes a highly focused femtosecond laser pulse to induce localized permanent modification within the light-transmitting medium layer 304 through nonlinear optical effects, thereby precisely increasing the refractive index in a specific region and forming a first waveguide structure 305 that can guide light waves, thus achieving a low-loss optical transmission path.

[0066] This disclosure also provides a method for manufacturing a packaging structure, such as... Figure 5 As shown, the manufacturing method includes: Step S100: Provide a substrate; Step S200: Set the optical chip on the substrate; Step S300: Form a light-transmitting dielectric layer located at the output / input end of the optical chip; Step S400: A first waveguide structure is formed within the light-transmitting dielectric layer using laser direct-write waveguide technology; the first waveguide structure is used to limit the transmission path of optical signals within the light-transmitting dielectric layer; Step S500: A coupler is disposed on the substrate; wherein, the light-transmitting dielectric layer is located between the output / input end of the optical chip and the coupler; the coupler is used to realize optical coupling between the first waveguide structure and the optical fiber.

[0067] like Figure 6 As shown, a substrate 301 is provided, and the optical chip 302 is fixed on the substrate 301. In this way, precise positioning and support can be provided for subsequent optical path design and packaging processes.

[0068] like Figure 8 As shown, a light-transmitting dielectric layer 304 is formed at the output / input end of the optical chip 302. The light-transmitting dielectric layer 304 is used to transmit optical signals between the optical chip 302 and the coupler.

[0069] Here, a light-transmitting dielectric layer 304 can be formed using a deposition process. The deposition processes involved in the embodiments of this disclosure include, but are not limited to, chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD).

[0070] Combination Figure 9 and Figure 10 As shown, after the light-transmitting dielectric layer 304 is formed, the femtosecond laser is precisely focused inside the light-transmitting dielectric layer 304 using the laser direct writing system 310 to change the refractive index of a local area in the light-transmitting dielectric layer 304, thereby forming a first waveguide structure 305 within the light-transmitting dielectric layer 304.

[0071] In some embodiments, a first waveguide structure 305 is formed within the light-transmitting dielectric layer 304 using laser direct-writing waveguide technology. This includes increasing the refractive index of the light-transmitting material in a portion of the light-transmitting dielectric layer 304 using laser direct-writing waveguide technology, thereby forming the first waveguide structure 305 within the region where the refractive index of the light-transmitting material is increased. Thus, the refractive index of the first waveguide structure 305 is slightly higher than that of the surrounding light-transmitting material, causing total internal reflection of the optical signal within the first waveguide structure 305, thereby reducing scattering losses.

[0072] In this embodiment, the first waveguide structure 305 formed in the light-transmitting dielectric layer 304 using laser direct-write waveguide technology can precisely control the transmission path of the optical signal without damaging the original light-transmitting characteristics of the light-transmitting material, thereby significantly reducing optical loss during transmission. Furthermore, since the implementation of laser direct-write waveguide technology does not introduce high temperatures, it does not cause additional impact on the temperature-sensitive optical chip 302, ensuring the stability of the device.

[0073] according to Figure 3 and Figure 4 As can be seen, the output / input terminal of the optical chip involved in this embodiment can be located either on the top surface or on the side of the optical chip. In this embodiment, the manufacturing method of the corresponding packaging structure varies depending on the specific location of the output / input terminal of the optical chip. The following describes the manufacturing method of the packaging structure... Figure 3 and Figure 4 The manufacturing methods of different packaging structures are described in detail.

[0074] In Scheme 1, the output / input terminals of the optical chip 302 are located on the top surface of the optical chip 302, such as... Figure 3 As shown. The specific manufacturing method of the packaging structure 300 is as follows: Step S10: Set the optical chip on the substrate; Step S20: Bond the electrical chip onto the optical chip; Step S30: Form a light-transmitting dielectric layer located at the output / input end of the optical chip; Step S40: Form the first waveguide structure within the light-transmitting dielectric layer using laser direct-write waveguide technology; Step S50: A coupler is disposed on the substrate, and the light-transmitting dielectric layer is located between the output / input end of the optical chip and the coupler.

[0075] In step S10, an optical chip wafer 601 is disposed on the substrate 301. The optical chip wafer 601 contains a plurality of optical chips 302 arranged in a horizontal array. The output / input terminal of each optical chip 302 is located at the edge of its top surface, such as... Figure 6 As shown.

[0076] In step S20, multiple electrical chips 306 are simultaneously bonded onto the optical chip wafer 601, and the multiple electrical chips 306 are connected one-to-one with the multiple optical chips 302, such as... Figure 7 As shown.

[0077] It should be noted here that bonding the electrical chip 306 to the top surface of the optical chip 302 means bonding the electrical chip 306 to the top surface of the non-output / input region of the optical chip 302 to achieve electrical connection between the electrical chip 306 and the optical chip 302. In this case, the output / input end of the optical chip 302 is located on the first surface where it contacts the electrical chip 306 and is not covered by the electrical chip 306.

[0078] In this embodiment of the disclosure, the optical chip 302 and the electrical chip 306 can be electrically connected by a die-to-wafer (D2W) bonding method.

[0079] In some embodiments, forming a light-transmitting dielectric layer 304 at the output / input end of the optical chip 302 includes: forming a light-transmitting dielectric layer 304 at the output / input end of the optical chip 302 and covering the sidewall of the optical chip 306, such as... Figure 8 As shown.

[0080] It should be noted that, since the size of the electrical chip 306 is smaller than that of the optical chip 302, after bonding the electrical chip 306 to the optical chip 302, a dielectric layer needs to be fabricated on the sidewall of the electrical chip 306 to form a continuous and dense package, achieving reliable electrical insulation and mechanical protection. At this time, the top of the electrical chip 306 and the top of the light-transmitting dielectric layer 304 are flush in a direction perpendicular to the substrate 301.

[0081] In this embodiment, a light-transmitting material is used to prepare a dielectric layer (i.e., a light-transmitting dielectric layer 304) covering the sidewall of the electrical chip 306, and a first waveguide structure 305 is formed in the light-transmitting dielectric layer 304, which reduces the transmission loss of optical signals while achieving electrical insulation and mechanical protection.

[0082] In some embodiments, after step S40, the manufacturing method of the packaging structure 300 further includes: cutting the entire structure along a preset dicing groove by means of precision mechanical sawing or advanced laser stealth cutting technology, thereby separating a large number of independent and fully packaged packaging structures containing a single optical chip 302 and an electrical chip 306 at one time.

[0083] After the dicing process, a coupler can be placed on the substrate 301. This places the light-transmitting dielectric layer 304 between the output / input terminal of the optical chip 302 and the coupler 303. The coupler 303 is responsible for efficiently coupling the optical signal transmitted in the first waveguide structure 305 to the external optical fiber, thereby completing the optical signal transmission from the optical chip to the external system.

[0084] In scheme two, the output / input terminals of optical chip 402 are located on the side of optical chip 402, such as... Figure 4 As shown. The specific manufacturing method of the package structure 400 is as follows: Step S11: Set the optical chip on the substrate; Step S21: Form a light-transmitting dielectric layer located at the output / input end of the optical chip; Step S31: Form the first waveguide structure within the light-transmitting dielectric layer using laser direct-write waveguide technology; Step S41: Bond the electrical chip onto the optical chip; Step S51: A coupler is placed on the substrate, and the light-transmitting dielectric layer is located between the output / input end of the optical chip and the coupler.

[0085] In step S11, multiple optical chips 402 arranged in an array can be disposed on the substrate 301, with the output / input terminal of each optical chip 402 located on the side of the optical chip 402.

[0086] In some embodiments, forming a light-transmitting medium layer 304 at the output / input end of the optical chip 402 includes: forming a light-transmitting medium layer 304 at the output / input end of the optical chip 402 and covering the sidewall of the optical chip 402.

[0087] It should be noted that, due to the gaps between the optical chips 402 array, the structure is fragile and difficult to process later. Therefore, a filler layer is formed between adjacent optical chips 402. The filler layer covers the output / input terminals located on the sides of the optical chips 402 to provide mechanical support and protection, achieve wafer-level planarization, and lay the foundation for subsequent dicing and electrical interconnection. At this time, the top of the optical chip 402 is flush with the top of the light-transmitting dielectric layer 304 in a direction perpendicular to the substrate 301.

[0088] In this embodiment, a light-transmitting material is used to prepare a filling layer (i.e., a light-transmitting medium layer 304) covering the sidewall of the optical chip 402, and a first waveguide structure 305 is formed in the light-transmitting medium layer 304, which reduces the transmission loss of optical signals while achieving mechanical support and protection for the optical chip 402.

[0089] In step S41, multiple electrical chips 306 are bonded to the arrayed optical chips 402, with each electrical chip 306 corresponding to one of the multiple optical chips 402. Here, the electrical connection between the optical chips 402 and the electrical chips 306 can be achieved through die-to-wafer (D2W) bonding.

[0090] After step S41, the entire structure can be cut along the preset dicing groove by means of precision mechanical sawing or advanced laser stealth cutting technology, thereby separating a large number of independent, fully packaged packaging structures containing a single optical chip 402 and an electrical chip 306 at one time.

[0091] After the dicing process is completed, a coupler 303 is placed on the substrate 301. This places the light-transmitting dielectric layer 304 between the output / input end of the optical chip 402 and the coupler 303. The coupler 303 is responsible for efficiently coupling the optical signal transmitted in the first waveguide structure 305 to the external optical fiber, thereby completing the optical signal transmission from the optical chip 402 to the external system.

[0092] It should be understood that the phrase "an embodiment" or "one embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this disclosure. Therefore, "in one embodiment" or "one embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this disclosure, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this disclosure. The sequence numbers of the above-described embodiments are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0093] The above description is merely a preferred embodiment of this disclosure and does not limit the patent scope of this disclosure. Any equivalent structural transformations made using the contents of this specification and drawings under the inventive concept of this disclosure, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this disclosure.

Claims

1. A packaging structure, characterized in that, The packaging structure includes: substrate; Optical chip and coupler located on the substrate; A light-transmitting dielectric layer that contacts the output and / or input terminals of the optical chip and the coupler; wherein the light-transmitting dielectric layer includes a first waveguide structure formed within the light-transmitting dielectric layer using laser direct-write waveguide technology; the first waveguide structure is used to limit the transmission path of the optical signal within the light-transmitting dielectric layer; the coupler is used to realize optical coupling between the first waveguide structure and the optical fiber.

2. The packaging structure according to claim 1, characterized in that, The packaging structure further includes: An electrical chip located on the substrate and electrically connected to the optical chip, the electrical chip being used to provide electrical drive signals to the optical chip and / or process the electrical signals transmitted by the optical chip.

3. The packaging structure according to claim 2, characterized in that, The area of ​​the electrical chip is smaller than the area of ​​the optical chip.

4. The packaging structure according to claim 2, characterized in that, The electrical chip is located on the optical chip and is electrically connected to the optical chip by bonding. The optical chip has a connection structure that extends through it along a first direction perpendicular to the surface of the substrate; the electrical chip is connected to the substrate through the connection structure.

5. The packaging structure according to claim 4, characterized in that, The output / input terminal of the optical chip is located on the first surface where the optical chip contacts the electrical chip; The optical chip has a second waveguide structure for transmitting optical signals extending along a second direction parallel to the surface of the substrate, and a reflector disposed in an optical path optically connected to the second waveguide structure for changing the transmission direction of the output / input optical signals of the second waveguide structure. The optical signal output from the second waveguide structure is coupled to the first waveguide structure via the mirror; or the optical signal output from the first waveguide structure is coupled to the second waveguide structure via the mirror.

6. The packaging structure according to any one of claims 1 to 4, characterized in that, The output / input terminals of the optical chip are located on the side of the optical chip; the optical chip has a second waveguide structure for transmitting optical signals extending along a second direction parallel to the surface of the substrate; The optical signal output from the second waveguide structure is coupled to the first waveguide structure; or the optical signal output from the first waveguide structure is coupled to the second waveguide structure.

7. The packaging structure according to claim 6, characterized in that, The optical chip includes at least two second waveguide structures that extend along the second direction and are spaced apart along the first direction; the at least two second waveguide structures together constitute an optical signal transmission channel inside the optical chip.

8. The packaging structure according to claim 1, characterized in that, The refractive index at the first waveguide structure in the light-transmitting medium layer is greater than the refractive index at the remaining locations in the light-transmitting medium layer.

9. The packaging structure according to claim 1, characterized in that, The material of the light-transmitting medium layer includes silicon oxide or aluminum oxide.

10. The packaging structure according to claim 1, characterized in that, The first waveguide structure has a circular, elliptical, or rectangular cross-section along the direction perpendicular to the light transmission direction.

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