On-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration and method

Abstract

The invention discloses an on-chip antenna and pulse source integrated device and method based on heterogeneous material 3D packaging integration, and relates to the technical field of antennas. The upper surface of the base substrate is used for installing a radiation structure; the upper surface of the photoconductive substrate is used for mounting an excitation structure; the interconnection structure is used for realizing electric connection between the radiation structure and the excitation structure, and the through hole is formed in the base substrate through a TSV or TGV process and penetrates through the whole base substrate; the conductive filling material is filled in the through hole; the solder balls are arranged on the lower surface of the through hole of the base substrate and are made of conductive weld-aid metal; the GSG electrode is arranged on the upper surface of the photoconductive substrate; the device adopts a 3D packaging technology, integrates a radiation structure and an excitation structure on the same chip, breaks through the frequency limitation of 110GHz of a traditional electrical pulse source, has the advantages of high-frequency performance, low dielectric loss, high integration level and the like, and is suitable for the fields of wireless communication, radar ranging systems and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and specifically to an on-chip antenna and pulse source integrated device and method based on heterogeneous material 3D packaging integration. Background Art

[0002] As a classic passive device, antennas are widely used in various fields. Their main function is to realize the mutual conversion between guided high-frequency alternating current and space-radiated electromagnetic waves. With the advent of the big data era, people's demand for high-speed data transmission is increasing day by day, and the frequency band of wireless communication is gradually increasing. At present, there are mature passive antenna design schemes in the industry, which support the design of passive antennas in the millimeter wave band. However, due to the leakage effect generated under size miniaturization, the operating frequency of the electrical pulse source is limited to below 110 GHz. Without the support of high-frequency pulse sources, high-frequency passive antennas are like castles in the air, which further restricts the development of high-frequency wireless communication.

[0003] To break through this bottleneck, new types of high-frequency electromagnetic wave emitting devices have been widely studied, such as photoconductive antennas, spin terahertz devices, photodiode antennas, etc. Compared with traditional passive antennas, these new types of devices do not require external current source excitation, so they break through the frequency limitation of current pulse sources. These devices use the photoelectric conversion characteristics of the substrate material to autonomously generate alternating current under the excitation of laser, and then form electromagnetic wave radiation. The latest research shows that these devices can generate electromagnetic wave radiation in the terahertz frequency range. However, at present, these devices also face many problems, such as difficult power improvement, limited modulation methods, and inability to be used as receiving antennas.

[0004] Existing radiation antenna devices are divided into two categories: active devices and passive devices. The advantages of passive devices are mature design schemes and many modulation means, but the disadvantages are limited by the frequency bottleneck of electrical pulses at 110 GHz; the advantages of active devices are that the frequency can break through the limitation of electrical pulse sources, but the disadvantages are limited radiation power, few modulation means, and inability to be used as a receiving module. Therefore, the specific form of the next-generation millimeter-wave transceiver system still needs to be further explored. Summary of the Invention

[0005] The present invention provides an on-chip antenna and pulse source integrated device and method based on heterogeneous material 3D packaging integration to solve the limitation problems of high-frequency electromagnetic wave radiation and receiving devices in the prior art, realize the radiation and reception of high-frequency electromagnetic waves above 110 GHz, and meet the requirements of high-frequency electromagnetic waves in fields such as wireless communication and radar ranging systems.

[0006] To achieve the above object, the present invention provides the following technical solution: An on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration, comprising: Base substrate: Made of a material with low dielectric loss, the upper surface of the base substrate is used to mount a radiation structure for emitting and receiving high-frequency electromagnetic waves; Photoconductive substrate: Made of a photoconductive material, the upper surface of the photoconductive substrate is used to mount an excitation structure for generating high-frequency alternating current under laser excitation; Interconnection structure: Used to achieve electrical connection between the radiation structure and the excitation structure, the interconnection structure includes: Through-hole: Opened on the base substrate by TSV or TGV process, penetrating the entire base substrate; Conductive filling material: Filled in the through-hole, formed by electroplating process; Solder ball: Set on the lower surface at the position of the through-hole of the base substrate, made of conductive solder metal; GSG electrode: Set on the upper surface of the photoconductive substrate, aligned and welded with the solder ball to achieve electrical interconnection between the base substrate and the photoconductive substrate.

[0007] Further, the base substrate is any one of silicon, glass or PCB material; the surface flatness of the base substrate is processed by polishing process.

[0008] Further, the photoconductive substrate is any one of GaAs or LnP materials.

[0009] Further, the conductive material filled in the through-hole is any one of copper, aluminum or gold.

[0010] Further, the material of the solder ball is conductive solder metal.

[0011] Further, the integrated device can achieve radiation and reception of high-frequency electromagnetic waves above 110 GHz.

[0012] Further, the radiation structure includes a microstrip antenna, a patch antenna or a horn antenna, and its designed frequency range is above 110 GHz.

[0013] Further, the excitation structure is a photoconductive antenna, and its structure includes a photoconductive switch and a transmission line, and the photoconductive switch generates high-frequency alternating current under laser excitation.

[0014] Further, the radiation structure and the excitation structure are optimized by the simulation design software HFSS to achieve the radiation and reception functions of high-frequency electromagnetic waves.

[0015] Preparation method of an on-chip antenna and a pulse source integrated device based on heterogeneous material 3D packaging integration, the method includes the following steps: Prepare a base substrate and a photoconductive substrate, where the base substrate is made of a low dielectric loss material and the photoconductive substrate is made of a photoconductive material; Open vias on the base substrate through TSV or TGV processes, and fill the vias with a conductive material through electroplating, and then perform a polishing process to ensure the flatness of the surface of the base substrate; Manufacture a radiation structure on the upper surface of the base substrate, where the radiation structure is used to emit and receive high-frequency electromagnetic waves; Manufacture an excitation structure on the upper surface of the photoconductive substrate, where the excitation structure is used to generate a high-frequency alternating current under laser excitation; Set solder balls on the lower surface at the position of the vias of the base substrate, and the solder balls are made of a conductive solder metal; Align the base substrate with the photoconductive substrate, make the solder balls correspond to the GSG electrodes on the upper surface of the photoconductive substrate, and achieve welding through a bonding process to complete the electrical interconnection between the base substrate and the photoconductive substrate; Perform performance testing and optimization on the integrated device after packaging.

[0016] Compared with the prior art, the present invention provides an on-chip antenna and pulse source integrated device and method based on heterogeneous material 3D packaging integration, which has the following beneficial effects: For the on-chip antenna and pulse source integrated device and method based on heterogeneous material 3D packaging integration, through the method of heterogeneous integration, the present invention breaks through the limitations of the photoelectric substrate material, integrates the high-frequency response characteristics of the photoelectric substrate with a low dielectric loss substrate such as glass, realizes the radiation and reception of high-frequency electromagnetic waves above 110 GHz, and meets the requirements of high-frequency wireless communication and radar ranging systems; adopts a base substrate material with low dielectric loss, and realizes the interconnection of different substrate materials through TSV / TGV processes and bonding packaging technologies, effectively reducing the transmission loss of high-frequency signals and improving the power efficiency of the device; packages the high-frequency pulse source and the millimeter-wave antenna on the same chip, reducing the complexity and volume of the system, and improving the reliability and stability of the system; combining the mature design scheme of the passive antenna and the high-frequency characteristics of the active device, the integrated device of the present invention not only has a high frequency, but also inherits various modulation means of the passive antenna, enhancing the functionality and flexibility of the system. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1Schematic diagram of the structure after opening holes in the base substrate of the on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration; Figure 2 Schematic diagram of the interconnection alignment between the radiation antenna of the on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration and the device on the photoconductive substrate below the substrate; Figure 3 Schematic diagram after electrode bonding of the on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration; Figure 4 Schematic diagram of manufacturing the radiation structure device on the base substrate of the on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration; Figure 5 Schematic diagram of manufacturing the excitation structure device on the upper surface of the photoconductive substrate of the on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration.

[0019] In the figure: 1. Excitation structure; 2. On-chip transmission structure; 3. Through-hole transmission structure; 4. Radiation structure. Detailed implementation manners

[0020] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following detailed description of the specific implementation manners of the present invention will be made in conjunction with the accompanying drawings of the specification.

[0021] In the following description, many specific details are set forth to fully understand the present invention. However, the present invention can also be implemented in other ways different from this description. Those skilled in the art can make similar generalizations without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0022] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that can be included in at least one implementation manner of the present invention. The "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it an embodiment that is separate from or mutually exclusive of other embodiments.

[0023] Please refer to Figures 1-5, the present invention discloses an on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration, including: a base substrate: made of a low dielectric loss material, the upper surface of the base substrate is used to mount a radiation structure 4, and the radiation structure 4 is used to transmit and receive high-frequency electromagnetic waves; a photoconductive substrate: made of a photoconductive material, the upper surface of the photoconductive substrate is used to mount an excitation structure 1, and the excitation structure 1 is used to generate high-frequency alternating current under laser excitation; an interconnection structure: used to achieve electrical connection between the radiation structure 4 and the excitation structure 1, and the interconnection structure includes: a through-hole: opened on the base substrate through TSV (Through-Silicon Via) or TGV (Through-Glass Via) process, penetrating the entire base substrate; a conductive filling material: filled in the through-hole and formed by electroplating process; a solder ball: arranged on the lower surface of the through-hole position of the base substrate, made of a conductive solder metal; a GSG (Ground-Signal-Ground) electrode: arranged on the upper surface of the photoconductive substrate, aligned and welded with the solder ball to achieve electrical interconnection between the base substrate and the photoconductive substrate; a bonding process is used for welding, and the bonding process is thermocompression bonding or ultrasonic bonding, which is used to achieve alignment welding between the solder ball and the GSG electrode.

[0024] For the on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration, the present invention breaks through the frequency limitation of traditional electrical pulse sources through heterogeneous integration, realizes the radiation and reception of high-frequency electromagnetic waves above 110 GHz, and meets the requirements of high-frequency wireless communication and radar ranging systems; uses a base substrate material with low dielectric loss, and realizes the interconnection of different substrate materials through TSV / TGV process and bonding packaging technology, effectively reducing the transmission loss of high-frequency signals and improving the power efficiency of the device; packages the high-frequency pulse source and the millimeter-wave antenna on the same chip, reducing the complexity and volume of the system, and improving the reliability and stability of the system; combining the mature design scheme of passive antennas and the high-frequency characteristics of active devices, the integrated device of the present invention not only has a high frequency, but also inherits various modulation means of passive antennas, enhancing the functionality and flexibility of the system.

[0025] Specifically, the base substrate is any one of silicon, glass or PCB materials; the surface flatness of the base substrate is processed by a polishing process to meet the requirements of integrated circuit processing technology. The conductive material filled in the through-hole is any one of copper, aluminum or gold; the material of the solder ball is a conductive solder metal, and the conductive solder metal includes but is not limited to tin, silver or their alloys.

[0026] Specifically, the photoconductive substrate is any one of GaAs or LnP materials; Specifically, the integrated device can achieve the radiation and reception of high-frequency electromagnetic waves above 110 GHz.

[0027] Specifically, the radiation structure 4 includes a microstrip antenna, a patch antenna or a horn antenna, and its designed frequency range is above 110 GHz; the excitation structure 1 is a photoconductive antenna, and its structure includes a photoconductive switch and a transmission line. The photoconductive switch generates a high-frequency alternating current under laser excitation; the radiation structure 4 and the excitation structure 1 are optimized by the simulation design software HFSS to achieve the functions of radiation and reception of high-frequency electromagnetic waves.

[0028] The present invention aims to solve the problems existing in the high-frequency electromagnetic wave transmitting and receiving devices in the prior art, and proposes an integrated device of an on-chip antenna and a pulse source based on heterogeneous material 3D packaging integration. By heterogeneously integrating a high-frequency pulse source and a millimeter-wave antenna, the problem of high dielectric loss of the traditional photoconductive substrate is effectively avoided, and at the same time, the functions of radiation and reception of high-frequency electromagnetic waves are realized, with high integration and low signal transmission loss. The specific technical means are as follows: Preparation of the base substrate and the photoconductive substrate: Select a silicon substrate with low dielectric loss as the base substrate, and use GaAs as the photoconductive substrate. The base substrate and the photoconductive substrate are respectively subjected to pretreatment such as cleaning and polishing to ensure that their surfaces are flat and clean.

[0029] Fabrication and filling of the vias: Use the TSV process to open vias on the silicon-based substrate, and the aperture size is determined according to the design requirements. The electroplating process is used to fill the vias with a conductive material such as copper or gold, and combined with the chemical mechanical polishing (CMP) process, the surface of the base substrate reaches the flatness required for integrated circuit processing.

[0030] Fabrication of the radiation structure 4 and the excitation structure 1: The radiation structure 4 is fabricated on the upper surface of the base substrate by micro-nano processing technology, and its structure is designed according to the required radiation frequency and radiation pattern. The excitation structure 1 is fabricated on the upper surface of the photoconductive substrate, and the photoconductive antenna structure is formed by processes such as photolithography and etching.

[0031] Setting and bonding of the interconnection structure: Solder balls are set on the lower surface of the via position of the base substrate, and the material is a conductive solder metal. Align the base substrate with the photoconductive substrate so that the solder balls at the via position of the base substrate correspond to the GSG electrodes on the upper surface of the photoconductive substrate. The solder balls and the GSG electrodes are welded by using a thermocompression bonding or ultrasonic bonding process to complete the interconnection of the base substrate and the photoconductive substrate.

[0032] Performance testing and optimization: Perform performance testing on the completed packaged integrated device, including the measurement of indicators such as frequency response, radiation power, and reception sensitivity. According to the test results, use the simulation design software HFSS to optimize and adjust the device structure to further improve the performance of the device.

[0033] The technical effects of the present invention are as follows: Breaking through the frequency limit: By heterogeneously integrating a high-frequency pulse source and a millimeter-wave antenna, the high dielectric loss caused by the high dielectric constant of the photoconductive substrate is avoided, realizing the radiation and reception of high-frequency electromagnetic waves above 110 GHz and breaking through the frequency limit of traditional electrical pulse sources.

[0034] Improving power and performance: Solving the problem of large electrical signal transmission loss between heterogeneous devices, meeting the power requirements in actual use, and improving the performance of high-frequency electromagnetic wave radiation and reception.

[0035] Easy to fabricate and integrate: Designed using 2.5D and 3D packaging as well as the simulation design software HFSS, and integrated with advanced manufacturing technologies such as TSV / TGV processes, electroplating processes, and bonding processes, realizing the integrated integration of a high-frequency pulse source and a passive antenna, which is easy for large-scale fabrication and integrated applications.

[0036] Wide range of applications: This integrated device can be widely applied in fields such as wireless communication and radar ranging, providing strong support for the development of high-frequency wireless communication.

[0037] A method for fabricating an on-chip antenna and pulse source integrated device based on 3D packaging integration of heterogeneous materials, the method comprising the following steps: Fabricating a base substrate and a photoconductive substrate, the base substrate being made of a low dielectric loss material and the photoconductive substrate being made of a photoconductive material; Opening a through-hole on the base substrate by TSV or TGV process, filling the through-hole with a conductive material by electroplating process, and then performing a polishing process to ensure the flatness of the surface of the base substrate; Fabricating a radiation structure 4 on the upper surface of the base substrate, the radiation structure 4 being used for emitting and receiving high-frequency electromagnetic waves; Fabricating an excitation structure 1 on the upper surface of the photoconductive substrate, the excitation structure 1 being used for generating a high-frequency alternating current under laser excitation; Setting solder balls on the lower surface at the position of the through-hole of the base substrate, the solder balls being made of a conductive solder metal; Aligning the base substrate with the photoconductive substrate, making the solder balls correspond to the GSG electrodes on the upper surface of the photoconductive substrate, and realizing welding through a bonding process to complete the electrical interconnection between the base substrate and the photoconductive substrate; Performing performance testing and optimization on the packaged integrated device.

[0038] This solution of the present application overcomes the problems existing in the 3D packaging integration technology of heterogeneous materials, realizing a preparation technology for on-chip antenna-pulse source integrated devices with low cost, high yield, high reliability, and easy mass production.

[0039] By adopting the bonding encapsulation technology, the antenna and the pulse source are integrated on the same surface, which simplifies the structure and reduces the manufacturing cost. The alignment welding of the solder balls on the lower surface of the via hole position and the GSS electrode on the upper surface of the photoconductive substrate effectively solves the problems of interface connection and signal transmission, and improves the reliability and consistency.

[0040] The TSV / TGV process precisely prevents the perforation of the substrate, ensuring the reliability of the device. The filling and polishing process of the conductive solder metal achieves the flatness requirement of the substrate surface, ensuring the yield rate of the device. The bonding process ensures the stable connection between devices and improves the reliability and consistency of the integrated device.

[0041] In summary, for the on-chip antenna and pulse source integrated device and method based on heterogeneous material 3D packaging integration, high-frequency performance: Through the 3D packaging integration technology, the radiation and reception of high-frequency electromagnetic waves are realized, breaking through the frequency limit of 110 GHz of traditional electrical pulse sources; low dielectric loss: Using low-dielectric-loss silicon or glass as the base substrate reduces the transmission loss of high-frequency signals; high integration: Through heterogeneous material 3D packaging integration, high-density integration of the on-chip antenna and the pulse source is achieved, improving the overall performance of the device; easy to manufacture: Adopting mature TSV / TGV processes and bonding processes, it is easy to mass-produce.

[0042] It should be understood that each part of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following technologies well known in the art can be used: discrete logic circuits with logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits with appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0043] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. An on-chip antenna and pulse source integrated device based on 3D packaging integration of heterogeneous materials, characterized in that: Comprising: Base substrate: Made of a low dielectric loss material, the upper surface of the base substrate is used for mounting a radiation structure, and the radiation structure is used for emitting and receiving high-frequency electromagnetic waves; Photoconductive substrate: Made of a photoconductive material, the upper surface of the photoconductive substrate is used for mounting an excitation structure, and the excitation structure is used for generating a high-frequency alternating current under laser excitation; Interconnection structure: Used to achieve electrical connection between the radiation structure and the excitation structure, the interconnection structure includes: Through-hole: Opened on the base substrate by TSV or TGV process, penetrating the entire base substrate; Conductive filling material: Filled in the through-hole, formed by electroplating process; Solder ball: Arranged on the lower surface at the position of the through-hole of the base substrate, made of a conductive solder metal; GSG electrode: Arranged on the upper surface of the photoconductive substrate, aligned and welded with the solder ball to achieve electrical interconnection between the base substrate and the photoconductive substrate.

2. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, characterized in that: The base substrate is any one of silicon, glass or PCB material; the surface flatness of the base substrate is processed by a polishing process.

3. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, characterized in that: The photoconductive substrate is any one of GaAs or LnP materials.

4. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, characterized in that: The conductive material filled in the through-hole is any one of copper, aluminum or gold.

5. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, wherein: The material of the solder ball is a conductive solder metal.

6. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, characterized in that: The integrated device can achieve radiation and reception of high-frequency electromagnetic waves above 110 GHz.

7. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, characterized in that: The radiation structure includes a microstrip antenna, a patch antenna or a horn antenna, and its designed frequency range is above 110 GHz.

8. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, characterized in that: The excitation structure is a photoconductive antenna, and its structure includes a photoconductive switch and a transmission line. The photoconductive switch generates a high-frequency alternating current under laser excitation.

9. The on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to claim 1, characterized in that: The radiation structure and the excitation structure are optimized by the simulation design software HFSS to achieve the radiation and reception functions of high-frequency electromagnetic waves.

10. The preparation method of the on-chip antenna and pulse source integrated device based on heterogeneous material 3D packaging integration according to any one of claims 1-9, characterized in that: The method includes the following steps: Prepare a base substrate and a photoconductive substrate, the base substrate is made of a low dielectric loss material, and the photoconductive substrate is made of a photoconductive material; Open a through-hole on the base substrate by TSV or TGV process, and fill the through-hole with a conductive material by electroplating process, and then perform a polishing process to ensure the flatness of the base substrate surface; Manufacture a radiation structure on the upper surface of the base substrate, and the radiation structure is used for emitting and receiving high-frequency electromagnetic waves; Manufacture an excitation structure on the upper surface of the photoconductive substrate, and the excitation structure is used for generating a high-frequency alternating current under laser excitation; Set a solder ball on the lower surface at the position of the through-hole of the base substrate, and the solder ball is made of a conductive solder metal; Align the base substrate with the photoconductive substrate, make the solder ball correspond to the GSG electrode on the upper surface of the photoconductive substrate, and achieve welding through a bonding process to complete the electrical interconnection between the base substrate and the photoconductive substrate; Perform performance testing and optimization on the integrated device after packaging.

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