Optical coupling structure and optical communication device

Abstract

The utility model provides an optical coupling structure and an optical communication device, the optical coupling structure comprises a transparent substrate, a super lens and a metal coating film, the transparent substrate comprises one or more conductive through holes, and the conductive through holes comprise through holes penetrating through the transparent substrate and conductive materials filled in the through holes. The super lens is located on one side of the transparent substrate in the thickness direction and fixedly connected with the transparent substrate. The metal coating film is arranged on the surface, away from the super lens, of the transparent substrate. The super lens is an advanced optical element, can realize accurate regulation and control on light wavefront, and can be combined with multiplexing technologies such as wavelength division, mode division and space division, so that the coupling efficiency of optical signals is effectively improved, and the data capacity and the signal quality are improved. Therefore, accurate regulation and control of the optical wavefront can be realized by using the super lens, and meanwhile, the super lens can be combined with multiplexing technologies such as wavelength division, mode division and space division, so that the coupling efficiency of optical signals is effectively improved, and higher data capacity and signal quality are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor packaging, and in particular relates to an optical coupling structure and an optical communication device. Background Art

[0002] With the rapid development of technologies such as 5G, cloud computing, artificial intelligence, and the Internet of Things, people's demand for communication capacity is increasing. Optical interconnection technology, with its advantages of high speed, large capacity, and low loss, has gradually replaced electrical interconnection and become an important information transmission method for data centers.

[0003] In optical communication technology, co-packaged optical modules (CPO) are optical modules and chips packaged together to achieve the function of mutual conversion between optical signals and electrical signals in optical fiber transmission. Compared with traditional optical modules, CPO reduces the transmission distance of optical signals on circuit boards, reduces power consumption and improves signal speed and quality, which can better meet the needs of high-speed, high-efficiency, and large-scale data processing in data centers.

[0004] In order to improve the transmission capacity of optical communication systems, technologies such as wavelength division multiplexing, mode division multiplexing and space division multiplexing have been developed to realize the transmission of optical signals of multiple wavelengths, modes or spaces in the same optical fiber.

[0005] The traditional technology of optical coupling using lenses and fiber arrays faces the problem of low coupling efficiency due to the long transmission distance, which leads to mode field mismatch between the optical signal and the fiber core. How to efficiently and accurately couple the optical signal from the optical chip to the fiber array is a problem that needs to be solved in optical communication technology. Utility Model Content

[0006] The purpose of the present invention is to solve the deficiencies in the prior art to at least a certain extent, to achieve precise control of the light wavefront, to improve the coupling efficiency of the optical signal, and to increase data capacity and signal quality.

[0007] To achieve the above object, the present invention provides an optical coupling structure, comprising:

[0008] A transparent substrate, comprising one or more conductive through holes, wherein the conductive through holes include through holes penetrating the transparent substrate and conductive materials filled in the through holes;

[0009] The super lens is located on one side of the transparent substrate in the thickness direction and is fixedly connected to the transparent substrate;

[0010] The metal coating is arranged on the surface of the transparent substrate facing away from the super lens.

[0011] The material of the transparent substrate is boric acid glass.

[0012] In one embodiment, the conductive material includes a redistribution layer at both ends of the through hole and a metal material in the middle region, and both ends of the metal material are electrically connected to the redistribution layer respectively.

[0013] In one of the embodiments, the diameter of the through hole for placing the redistribution layer is larger than the diameter of the through hole for placing the metal material.

[0014] In one embodiment, a plurality of super lenses are provided, and the plurality of super lenses are spaced apart along the surface direction of the transparent substrate.

[0015] The present application also provides an optical communication device, including the optical coupling structure provided in any of the above embodiments, and also including a PCB board, an optoelectronic chip assembly and an optical fiber array. The PCB board is attached to one side of a transparent substrate with a metal coating, and the optoelectronic chip assembly is attached to the other side of the transparent substrate on which a superlens is arranged. The optical fiber array covers the superlens, and the PCB board supplies power to the optoelectronic chip assembly and the optical fiber array through a conductive through hole.

[0016] In one of the embodiments, the optoelectronic chip assembly includes an optical chip and an electrical chip, the optical chip and the electrical chip are electrically connected, and the optical chip is electrically connected to the PCB board through a conductive through hole.

[0017] In one embodiment, the optical chip covers the surface of at least one metalens.

[0018] In one of the embodiments, the optical chip includes a horizontal optical connection portion and an optical coupler, the horizontal optical connection portion and the optical coupler are optically connected, and the optical coupler covers the surface of at least one metalens to achieve a vertical coupling optical connection.

[0019] In one embodiment, it further includes a plurality of electrical connection parts, each of which is a micro-bump array or a solder joint array, and is used as an electrical connection medium between the conductive material and each component.

[0020] The superlens is an advanced optical element that can achieve precise control of the light wavefront through special design. At the same time, it can also be combined with multiplexing technologies such as wavelength division, mode division and space division to effectively improve the coupling efficiency of optical signals and increase data capacity and signal quality. Therefore, this application can achieve precise control of the light wavefront through the use of a superlens. At the same time, it can also be combined with multiplexing technologies such as wavelength division, mode division and space division to effectively improve the coupling efficiency of optical signals and increase data capacity and signal quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 is a schematic diagram of the overall structure of the optical coupling structure in an embodiment of the present invention;

[0023] Figure 2 is a front view of an optical communication device in an embodiment of the present invention;

[0024] Figure 3 is the arrangement diagram in the superlens;

[0025] Figure 4 Schematic diagram of the structure of an optical communication device in an embodiment of the present invention.

[0026] In the accompanying drawings, the various reference numerals represent: glass substrate 1, through hole 10, redistribution layer 11, metal coating 12; superlens 13; optical coupling structure 2; electrical connection part 20; PCB board 3; electrical chip 4; optical chip 5; horizontal optical connection part 51; optical coupler 52; optical fiber array 6; electrical element 7. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but are not to be construed as limiting the present invention. All other embodiments obtained by ordinary technicians in the field without creative work based on the embodiments of the present invention are within the scope of protection of the present invention.

[0028] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “circumferential”, “radial”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0029] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0030] See also Figure 1 The present invention provides an optical coupling structure 2, the main structure of which is a transparent substrate. The transparent substrate used in this application is a glass substrate 1, which includes one or more conductive through holes, and the conductive through holes include a through hole 10 that penetrates the glass substrate 1 and a conductive material filled in the through hole 10. A super lens 13 is located on one side of the glass substrate 1 in the thickness direction and is fixedly connected to the glass substrate 1. A metal coating 12 is provided on the surface of the glass substrate 1 away from the super lens 13.

[0031] In the above embodiment, when the optical coupling structure 2 encapsulates the optical chip 5, the conductive through hole 10 can be used to connect the optical chip 5 and the power supply device to enable the optical chip 5 to be powered on. Since the glass substrate 1 has high resistivity, low electrical loss, and has an adjustable coefficient of thermal expansion and good mechanical strength. Therefore, the glass substrate 1 has a better power-on effect. The superlens 13 is an advanced optical element. Through special design, it can achieve precise control of the light wavefront. At the same time, it can also be combined with multiplexing technologies such as wavelength division, mode division and space division to effectively improve the coupling efficiency of the optical signal and improve higher data capacity and signal quality. The optical signal is emitted from the optical chip 5 through the glass substrate 1 to the metal coating 12. The metal coating 12 reflects the optical signal and returns to the superlens 13. After coupling and separation, the superlens 13 obtains a more accurate optical signal and transmits it to the receiving device.

[0032] In the above embodiments, the material of the glass substrate 1 is generally silicon dioxide, and the glass substrate 1 may also be made of borosilicate. In another example, the glass substrate 1 may be made of quartz. Alternatively, the glass substrate 1 may be made of one or more of the following until all of them: borosilicate, aluminosilicate, and quartz including single crystal quartz and synthetic quartz. Alternatively, the glass substrate 1 may be made of any suitable alternative glass substrate 1 material or a combination thereof. Alternatively, the substrate may be made of sapphire, silicon, zinc oxide, zirconium oxide including yttrium-stabilized zirconium oxide, ceramic or a combination thereof. In some examples, the glass substrate 1 may be lead-free, that is, it may not contain lead, lead oxide, lead alloy, lead compound and all lead components. In one example, the thermal expansion coefficient of the glass substrate 1 may be from about 0.05 ppm per degree Celsius to about 15 ppm per degree Celsius.

[0033] The present application can achieve precise control of the light wavefront by using the superlens 13. At the same time, it can also be combined with multiplexing technologies such as wavelength division, mode division and space division to effectively improve the coupling efficiency of optical signals and increase data capacity and signal quality.

[0034] In the above embodiment, the through hole 10 can be formed in the glass substrate 1 by etching and electroplating. For example, one or more through holes 10 can be formed in the glass substrate 1 by laser drilling and etching, and then a conductive material layer is provided on the inner surface of the one or more through holes 10 to form the one or more conductive through holes. Specifically, for example, a bottom-up electroplating method can be used to fill the inner surface of the one or more through holes 10 with a conductive material, thereby forming a conductive through hole.

[0035] See also Figure 1 Specifically, in one embodiment, the conductive material includes a redistribution layer 11 at both ends of the through hole 10 and a metal material in the middle region, and both ends of the metal material are electrically connected to the redistribution layer 11. The metal material is generally copper or silver, and the redistribution layer 11 is a single-layer or multi-layer electrical wiring structure, and the material is generally copper.

[0036] See also Figure 1 In one embodiment, the diameter of the area of ​​the through hole 10 for placing the redistribution layer 11 is larger than the diameter of the area of ​​the through hole 10 for placing the metal material.

[0037] Specifically, from Figure 1 It can be seen that the diameter of the through hole 10 at the two surfaces of the glass substrate 1 is larger than the diameter of the through hole 10 in the middle area. The large diameter through hole 10 is used to place the redistribution layer 11, thereby improving the conductivity of the redistribution layer 11, and the small diameter through hole 10 is used to place metal materials, such as copper wires. The small diameter through hole 10 is conducive to reducing the loss of current transmitted by the metal material and making the current signal more complete.

[0038] participate Figure 3 In one embodiment, a plurality of super lenses 13 are provided, and the plurality of super lenses 13 are arranged at intervals along the surface direction of the transparent substrate. The super lens 13 is made of microstructure units arranged in a periodic circular or rectangular pattern on the upper surface of the glass substrate 1. The microstructure unit is a circular convex column or a square convex column. The material of the microstructure unit is silicon. The periodic regular arrangement of the plurality of super lenses 13 can make the light coupling efficiency and quality higher.

[0039] participate Figure 2The present application also provides an optical communication device, including the optical coupling structure 2 provided in any of the above embodiments, and also including a PCB board 3, an optoelectronic chip 4 component and an optical fiber array 6. The PCB board 3 is attached to a side of the glass substrate 1 provided with a metal coating 12, and the optoelectronic chip 4 component is attached to the other side of the glass substrate 1 where a super lens 13 is arranged. The optical fiber array 6 covers the super lens 13, and the PCB board 3 supplies power to the optoelectronic chip 4 component and the optical fiber array 6 through the conductive through hole 10.

[0040] In the above embodiment, the input signal is modulated, amplified, transmitted and received through the coordinated work of the optoelectronic chip 4 components, and the multiplexing of optical signals is realized in combination with the superlens 13. While realizing the mutual conversion of electrical signals and optical signals and the function of data transmission, the capacity of optical communication is also improved, meeting the use needs of various application scenarios such as data centers and high-performance computing.

[0041] Specifically, in one embodiment, the optoelectronic chip 4 assembly includes an optical chip 5 and an electrical chip 4 , the optical chip 5 and the electrical chip 4 are electrically connected, and the optical chip 5 is electrically connected to the PCB board 3 through a conductive through hole 10 .

[0042] In one embodiment, a plurality of electrical connection parts 20 are further included. The electrical connection parts 20 are all micro-bump arrays or solder joint arrays. The electrical connection parts 20 are used as electrical connection media between the conductive material and each component.

[0043] Specifically, one or more conductive bumps are arranged on the glass substrate 1 as electrical connection parts 20, which are electrically connected to the conductive material and the electrical components respectively. The conductive bumps can be controllable collapse chip connection bumps, ball grid array connectors, solder balls, metal pillars, micro bumps, etc. The conductive bumps can include conductive materials such as solder, copper, aluminum, gold, nickel, silver, palladium, tin, etc. or combinations thereof.

[0044] In some embodiments, the conductive bumps may be formed by first forming a solder layer by common methods such as evaporation, electroplating, printing, etc. In some embodiments, the conductive bumps are metal pillars, such as copper pillars, formed by sputtering, electroplating, chemical plating, etc.

[0045] In one embodiment, the optical chip 5 covers the surface of at least one superlens 13 .

[0046] Specifically, in one embodiment, the optical chip 5 includes a horizontal optical connection portion 51 and an optical coupler 52, the horizontal optical connection portion 51 and the optical coupler 52 are optically connected, and the optical coupler 52 covers the surface of at least one superlens 13 to achieve vertical coupling optical connection, thereby improving the transmission quality and coupling accuracy of the optical signal.

[0047] After the optical chip 5 is optically connected to the optical coupler 52 through the horizontal optical connection part 51, it passes through the super lens 1313 and the metal coating 12, and is coupled to the optical fiber array 6 through the super lens 13 again. After the light propagates into the optical fiber through the above process, the coupling efficiency is higher than that of the traditional end face coupling and grating coupling, and the space division, mode division or wavelength division multiplexing function can be realized.

[0048] In the embodiment provided in the present application, after the optical chip 5 is optically connected to the superlens 13, it is reflected by the metal coating 12 and optically connected to the optical fiber through the superlens 13 again. The optical fiber array 6 is coupled and packaged with the superlens 13 by coupling packaging. The optical fiber array 6 includes but is not limited to a single-mode optical fiber array 6, a multi-mode optical fiber array 6 and a multi-core optical fiber according to different application scenarios. The types of electrical chips 4 include but are not limited to drivers and TIAs. The types of optical chips 5 include but are not limited to EMLs and PDs.

[0049] Preferably, see Figure 4 In one embodiment, an electrical component 7 is also mounted on the surface of the glass substrate 1. The electrical component 7 is located on the same surface as the optical chip 5 and the electrical chip 4. An electrical connection portion 20 is provided between the electrical component 7 and the glass substrate 1. The electrical component 7 is electrically connected to the optoelectronic chip 4 component through the electrical connection portion 20 and the redistribution layer 11.

[0050] The electrical components 7 include but are not limited to capacitors, inductors and resistors. The electrical components 7 are used to meet the electrical circuit requirements of the electrical chip 4 and the optical chip 5 to enable them to work normally.

[0051] The optical communication device is designed in a hybrid packaging form of a PCB board 3, an optical coupling structure 2, an electric chip 4, an optical chip 5, an optical fiber array 6 and an electrical component 7. The electric chip 4 and the optical chip 5 are powered by the PCB board 3 and the optical coupling structure 2, so that the electric chip 4 and the optical chip 5 complete the modulation, amplification, conversion and output processing of the electro-optical signal, and output the optical signal through the optical fiber or transmit the electric signal to the subsequent circuit.

[0052] Compared with the prior art, the super-optical coupling structure 2 and the optical communication device of the present invention have the following beneficial effects: a glass through hole 10 is provided inside the glass, and the glass through hole 10 has excellent high-frequency electrical properties. At the same time, the glass material has good physical, thermal and mechanical properties, which ensures the stability of the glass. A super lens 13 is also provided on the glass surface to realize the multiplexing of optical signals and the coupling with the optical fiber array 6. This optical communication device can realize high-speed, high-quality and large-capacity information transmission, and meet the use needs of various application scenarios such as data centers and high-performance computing.

[0053] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0054] The above is a description of the technical solution provided by the present invention. For those skilled in the art, according to the ideas of the embodiments of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An optical coupling structure, characterized in that: include: A transparent substrate, comprising one or more conductive through holes, wherein the conductive through holes include through holes penetrating the transparent substrate and conductive materials filled in the through holes; A super lens, located on one side of the transparent substrate in the thickness direction and fixedly connected to the transparent substrate; The metal coating is arranged on the surface of the transparent substrate facing away from the super lens.

2. The optical coupling structure according to claim 1, characterized in that: The transparent substrate is made of boric acid glass.

3. The optical coupling structure according to claim 1, characterized in that: The conductive material includes a redistribution layer at both ends of the through hole and a metal material in the middle area, and both ends of the metal material are electrically connected to the redistribution layer respectively.

4. The optical coupling structure according to claim 3, characterized in that: The area diameter of the through hole for placing the redistribution layer is greater than the area diameter of the through hole for placing the metal material.

5. The optical coupling structure according to claim 1, characterized in that: A plurality of super lenses are provided, and the plurality of super lenses are spaced apart along the surface direction of the transparent substrate.

6. An optical communication device, comprising the optical coupling structure according to any one of claims 1 to 5, characterized in that: It also includes a PCB board, an optoelectronic chip assembly and an optical fiber array. The PCB board is attached to the side of the transparent substrate provided with the metal coating, the optoelectronic chip assembly is attached to the other side of the transparent substrate on which the superlens is arranged, the optical fiber array covers the superlens, and the PCB board supplies power to the optoelectronic chip assembly and the optical fiber array through the conductive through hole.

7. The optical communication device according to claim 6, characterized in that: The optoelectronic chip assembly comprises an optical chip and an electrical chip, the optical chip and the electrical chip are electrically connected, and the optical chip is electrically connected to the PCB board through the conductive through hole.

8. The optical communication device according to claim 7, characterized in that: The optical chip covers the surface of at least one of the super lenses.

9. The optical communication device according to claim 8, characterized in that: The optical chip includes a horizontal optical connection portion and an optical coupler, the horizontal optical connection portion and the optical coupler are optically connected, and the optical coupler covers the surface of at least one of the super lenses to achieve vertical coupling optical connection.

10. The optical communication device according to claim 6, characterized in that: It also includes a plurality of electrical connection parts, each of which is a micro-bump array or a solder point array, and is used as an electrical connection medium between the conductive material and each component.

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