Terahertz three-dimensional link interconnection-oriented bistable adjustable pseudo surface plasmon waveguide and preparation method thereof

Abstract

The invention discloses a terahertz three-dimensional link interconnection-oriented bistable adjustable pseudo surface plasmon waveguide and a preparation method thereof, and belongs to the technical field of terahertz on-chip communication, the waveguide comprises a feed structure, an actuator, a patterned metal patch, a flexible dielectric substrate and a fiber-reinforced active layer, wherein the fiber-reinforced active layer is provided with a positive thermal response area and a negative thermal response area, S-shaped bending can be generated under photo-thermal excitation, and dynamic switchable interconnection between chips with different heights in a three-dimensional space is achieved. The working frequency band of the waveguide is 31.56-127.71 GHz, the relative bandwidth reaches 120%, the insertion loss is lower than 1.5 dB, and the waveguide has the characteristics of low loss, ultra wide band and bistable holding. The preparation method comprises the steps of waveguide main body structure processing, fiber reinforced active layer compounding, actuator integration and overall assembly. The method solves the problems that the existing terahertz interconnection dimension is limited and the resource allocation is fixed, and is suitable for a high-density three-dimensional integrated and dynamic reconfigurable system on chip.

Description

Technical Field

[0001] This invention belongs to the field of terahertz on-chip communication technology, specifically relating to a bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection and its fabrication method. Background Technology

[0002] Among the three key elements of artificial intelligence—algorithms, data, and computing power—computing power has become a crucial resource supporting the innovation and implementation of AI applications, as algorithms become increasingly complex and data volumes grow rapidly. However, the nanometer manufacturing process of integrated circuits is gradually approaching its physical limits, and relying solely on shrinking transistor feature sizes to improve chip computing power is facing enormous challenges. To continue the development trend of Moore's Law, multi-chip interconnect architectures have emerged. This architecture can provide richer computing and storage resources while maintaining spatial integration, and through reasonable task allocation, achieve a breakthrough improvement in computing scale and capability under the new architecture.

[0003] Currently, traditional chip interconnect technologies mainly fall into two categories: electrical interconnects and optical interconnects. Electrical interconnects achieve on-chip communication through metal transmission lines. Although the technology is mature, it suffers from relatively low bandwidth and high transmission loss. Optical interconnects utilize ultra-wideband optical fibers to achieve high-speed wired communication, but the system integration complexity is high, and it is sensitive to environmental conditions, making it difficult to achieve large-scale, low-cost deployment in on-chip systems. The terahertz band, located between microwaves and infrared light waves, utilizes high-frequency, high-speed electronic devices and low-loss quasi-optical waveguides to achieve wide bandwidth, high energy efficiency, and low cost interconnection methods, giving it significant advantages in next-generation on-chip interconnects and 3D integrated systems.

[0004] Nevertheless, existing terahertz interconnect technologies still face several key challenges that restrict their practical application: First, existing interconnect paths are mainly limited to two-dimensional planes, with limited planar wiring resources, making it difficult to fully utilize vertical space to achieve three-dimensional interconnects; Second, once the interconnect system is fabricated, the allocation of interconnect resources is basically fixed, lacking the ability to dynamically schedule and reconfigure computing resources during operation.

[0005] With the rapid development of information and communication technologies, chip interconnects have placed higher demands on data transmission rates, device size, and system flexibility. Therefore, achieving a combination of high relative bandwidth, high integration, and dynamic interconnection capabilities has become a core technological challenge that urgently needs to be overcome in this field. Based on this, designing and implementing a terahertz waveguide structure that combines three-dimensional interconnection capabilities, ultra-wideband transmission characteristics, and reconfigurability is of great significance for promoting the development of next-generation wireless communication and intelligent computing technologies. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of insufficient terahertz interconnect dimensions, fixed resource allocation, and limited dynamic interconnection capabilities in existing technologies, and to provide a bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection. This waveguide can achieve dynamic and stable interconnection between different chip processing regions in three-dimensional space, and has the advantages of low loss, ultra-wideband, and good structural fabrication. This invention achieves low-loss ultra-wideband transmission of terahertz surface waves through an artificial surface plasmon structure. It uses two polymers with different coefficients of thermal expansion to form the active layer of a flexible actuator, enabling the actuator to achieve bidirectional bending with positive and negative curvatures under external excitation. Furthermore, it utilizes polyimide fibers with low coefficients of thermal expansion as the internal support framework of the active layer, introducing residual stress and deformation constraints to achieve the bistable characteristics of the flexible actuator. Through the above structural design, switchable interconnection between chips at different height levels in three-dimensional space is achieved, thereby constructing an ultra-wideband dynamic interconnection waveguide structure suitable for terahertz chip three-dimensional link interconnection. This three-dimensional interconnected waveguide achieves dynamic control of the interconnection path in three-dimensional space while ensuring operating bandwidth and transmission performance. Furthermore, the device has a mature manufacturing process, readily available materials, and is easy to implement in engineering and system integration, thus showing promising application prospects.

[0007] This invention is achieved through the following technical solution:

[0008] A bistable tunable pseudosurface plasmonic waveguide for terahertz three-dimensional link interconnection has a feed structure 1 at both ends and an actuator 2 in the middle along the signal transmission direction. The waveguide is composed of a patterned metal patch 3, a flexible dielectric substrate 4, and a fiber-reinforced active layer 5 from top to bottom. The patterned metal patch 3 consists of a fishbone-shaped central patch 11 and surrounding metal side strips 12. The fishbone-shaped central patch 11 has a periodic structure with a uniform middle section and gradually changing ends. The fiber-reinforced active layer 5 is located below the uniform middle section of the fishbone-shaped central patch 11. The fiber-reinforced active layer 5 includes a positive thermal response region 6 and a negative thermal response region 7. The active layer 6 is located at both ends of the waveguide. The patterned metal patch 3 and the flexible dielectric substrate 4 constitute the feeding structure 1. The patterned metal patch 3, the flexible dielectric substrate 4, and the fiber-reinforced active layer 5 located in the middle section of the waveguide constitute the actuator 2. The terahertz signal enters from the feeding structure 1 at the input end and is coupled to the actuator 2. Under no excitation conditions, the actuator 2 is in a horizontal state, and the signal is output from the feeding structure 1 at the output end. Under photothermal excitation conditions, the positive thermal response region 6 bends in the positive curvature direction, and the negative thermal response region 7 bends in the negative curvature direction. The resulting S-shaped bending shape allows the free end of the actuator 2 to form surface contact with the feeding structures 1 at the output ends of different height levels, realizing ultra-wideband low-loss dynamic interconnection.

[0009] Furthermore, the power supply structure of the output terminal includes multiple power supply structures placed at different height positions, serving as output terminals at different heights in a three-dimensional interconnection.

[0010] Furthermore, the patterned metal patch 3 includes, along the signal transmission direction: a coplanar waveguide segment 13 at the input end, a mode matching segment 14 adjacent to the coplanar waveguide segment 13 at the input end, a periodic structure segment 15 in the middle, a mode matching segment 14 at the output end, and a coplanar waveguide segment 13 adjacent to the mode matching segment 14 at the output end; wherein, the periodic structure segment 15 is located in the middle uniform segment of the fishbone-shaped center patch 11.

[0011] Furthermore, the main bone width of the fish skeleton-type central patch 11 is 0.02–0.04λ, the branch bone period is 0.06–0.08λ, and the branch bone width is 0.02–0.04λ.

[0012] The length of the coplanar waveguide segment 13 is 0.06 to 0.08λ, the length of the support bone is 0, and the distance between it and the metal side strip 12 is 0.002 to 0.006λ.

[0013] The length of the pattern matching segment 14 is 0.6 to 0.8λ, the length of the shank gradually changes from 0.006 to 0.008λ at the end to 0.06 to 0.08λ at the center, and the distance between it and the metal sill 12 gradually changes from 0.002 to 0.006λ at the end to 0.02 to 0.04λ at the center.

[0014] The length of the periodic structural segment 15 is 0.06 to 0.08λ, the length of the branch bone is 0.06 to 0.08λ, and the distance between it and the metal side strip 12 is 0.02 to 0.04λ.

[0015] The length of the feed structure 1 is Width is The length of the actuator 2 is Width is ;

[0016] in, The wavelength corresponds to the center frequency of the operating frequency band.

[0017] Furthermore, the thickness of the patterned metal patch 3 is The thickness of the flexible dielectric substrate 4 is The thickness of the fiber-reinforced active layer 5 is 0.04~0.06λ, and the length ratio of the positive thermal response region 6 to the negative thermal response region 7 is 0.1~10.

[0018] Furthermore, the positive thermal response zone 6 is composed of a polymer 8 with a positive thermal expansion coefficient and fiber 10, and the negative thermal response zone 7 is composed of a polymer 9 with a negative thermal expansion coefficient and fiber 10; the fiber 10 is uniformly laid in the fiber-reinforced active layer 5.

[0019] Furthermore, the polymer 8 with a positive coefficient of thermal expansion is selected from polydimethylsiloxane or thermoplastic polyurethane elastomer; the polymer 9 with a negative coefficient of thermal expansion is selected from liquid crystal elastomer or liquid crystal polymer network; and the fiber 10 is selected from polyimide fiber or aramid fiber, with a layup density of 3 to 8 fibers / cm.

[0020] Furthermore, the contact area between the actuator 2 and the power supply structure 1 at the output end forms a surface contact area of... The bending height of the actuator 2 under photothermal excitation is 0.25~5λ, and the steady-state holding time is 1~8 s.

[0021] Furthermore, the waveguide operates in the range of 31.56~127.71 GHz, with a relative bandwidth of up to 120%, insertion loss below 1.5 dB, return loss below -15 dB, and steady-state sustaining time up to [missing value]. .

[0022] On the other hand, the present invention provides a method for fabricating a bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection, specifically including the following steps:

[0023] S1. Fabrication of the waveguide main structure: A metal layer is deposited on a flexible dielectric substrate, and a patterned metal patch is formed by a subtractive manufacturing process. The patterned metal patch includes a fishbone-shaped center patch and metal side strips. The patterned metal patch 3 includes, along the signal transmission direction: coplanar waveguide segments at both ends, mode matching segments adjacent to the coplanar waveguide segments, and periodic structure segments in the middle.

[0024] S2. Preparation of the fiber-reinforced active layer: The fiber is combined with a polymer with a positive thermal expansion coefficient to form a positive thermal response composite film; the fiber is combined with a polymer with a negative thermal expansion coefficient to form a negative thermal response composite film; the positive thermal response composite film and the negative thermal response composite film are spliced ​​together to form a fiber-reinforced active layer containing a positive thermal response region and a negative thermal response region.

[0025] S3. Integration of the actuator: The fiber-reinforced active layer obtained in step S2 is bonded to the lower surface of the flexible dielectric substrate corresponding to the middle section of the waveguide in step S1, so that the fiber-reinforced active layer is located directly below the periodic structure section in the middle of the patterned metal patch, thereby forming an actuator.

[0026] S4. Overall assembly: Fix the structure obtained in step S3 onto the carrier substrate to complete the integration of the waveguide.

[0027] The working principle of a bistable tunable pseudosurface plasmonic waveguide for terahertz three-dimensional link interconnection according to the present invention is as follows:

[0028] Artificial surface plasmon polaritons (SSPPs) are artificial periodic structures that can simulate the physical characteristics of surface plasmon polaritons (SPPs) in the optical or infrared frequency bands in the microwave, millimeter-wave, and terahertz frequency bands. SSPP propagation exhibits the following characteristics: First, SSPPs are surface waves tightly bound at the interface between the metal structure and the dielectric material, with their wave vector propagating along the interface direction; second, the plasma frequency of the structured surface is much lower than that of the metal bulk, thus achieving lower transmission loss in the target frequency band; third, their dispersion characteristics are closely related to the unit geometry, and by rationally designing the periodic structure parameters of the metal surface, the transmission performance of SSPP transmission lines in the operating frequency band can be optimized. This invention employs a gradient ground wire and a gradient slot structure to achieve broadband matching of wave amplitude and wave impedance, enabling terahertz signals to efficiently transition from traditional coplanar waveguides to SSPP transmission lines and be guided as surface waves.

[0029] Flexible photothermal actuators typically consist of a low-coefficient inert layer, a high-coefficient active layer, and a photothermal conversion material. When a certain amount of light is applied, the photothermal conversion material converts the absorbed light energy into heat energy. Under the same temperature change, the inert layer and the active layer undergo different degrees of thermal expansion, introducing bending deformation at the interface, usually bending in a single curvature direction. This invention uses two polymer materials with different coefficients of thermal expansion to form the active layer. When the applied excitation conditions are constant, the polymer with a positive coefficient of thermal expansion on one side tends to bend in the positive curvature direction, while the polymer with a negative coefficient of thermal expansion on the other side bends in the negative curvature direction, forming a bidirectional bending characteristic with both positive and negative curvatures. This allows for effective contact and selective switching with chips at different height levels in a three-dimensional interconnect structure.

[0030] Furthermore, flexible actuators with bistable characteristics can rapidly transform from one stable state to another under external stimuli and maintain a stable shape after the external stimulus is removed. Based on fiber layup, the bistable structure utilizes the high stiffness of fibers to construct a viscous resistance field through the interfacial shear stress between the fiber and polymer, increasing the energy barrier for polymer chain relaxation, extending the effective relaxation time, and thus achieving superior steady-state retention capability. This invention uses fibers with low coefficients of thermal expansion and a predetermined layup method. When the fibers and polymer are combined to form a fiber-reinforced polymer layer, the fibers constrain the deformation of the polymer molecular chains, thereby realizing the bistable transition and retention function of the actuator between two geometric configurations.

[0031] Compared with the prior art, the advantages of the present invention are as follows:

[0032] 1. The bistable tunable pseudosurface plasmon waveguide of the present invention for terahertz three-dimensional link interconnection operates in the terahertz band and has an ultra-wide operating bandwidth, which can support high-speed data transmission. It shows important technical potential and application value in application scenarios such as terahertz on-chip signal three-dimensional routing and high-density integrated interconnection.

[0033] 2. The artificial surface plasmonic surface waveguide structure has the characteristics of compact structure, strong electromagnetic field confinement capability and low transmission loss. It is suitable for interconnection between three-dimensional chips in the terahertz band, which helps to improve interconnection density and make full use of the vertical space resources in chip stacking.

[0034] 3. By using a flexible dielectric substrate as an inert layer and a polymer composite layer with opposite thermal expansion coefficients as an active layer, combined with fiber layup reinforcement, the actuator's S-shaped bending and bistable characteristics are achieved. This enables stable and switchable dynamic interconnection between chip layers of different heights, improving the flexibility and reliability of system scheduling.

[0035] 4. The selected metal and polymer materials are all common and readily available. The process covers conventional thin film deposition and patterned micromachining techniques. The preparation process is relatively simple and low-cost, with good process compatibility and prospects for large-scale application. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0037] Figure 1This is a schematic diagram of the structure of the ultrawideband bistable tunable pseudosurface plasmon waveguide for terahertz chip three-dimensional link interconnection application of the present invention.

[0038] Wherein, a is a top view of the entire structure, b is a front view of the entire structure, and c is a top view of a partial structure;

[0039] Figure 2 This is a schematic diagram of the actuator of the present invention;

[0040] Where a is a schematic diagram of the overall structure of the actuator, and b is a schematic diagram of the layered structure of the actuator.

[0041] Figure 3 These are schematic diagrams illustrating the form of the present invention under different excitation conditions;

[0042] Wherein, a is a deformation state diagram of the present invention under natural conditions, and b is a deformation state diagram of the present invention under excited conditions.

[0043] Figure 4 This is a schematic diagram illustrating the transmission performance of the present invention under different excitation conditions;

[0044] Wherein, a is a schematic diagram of the S-parameters of the first height level chip in three-dimensional space under natural conditions, and b is a schematic diagram of the S-parameters of the second height level chip in three-dimensional space under stimulated conditions.

[0045] Figure 5 The graph shows the stability test results of the actuator of this invention.

[0046] Where, a is the height change curve of the free end of the actuator during 50 repetitive tests, and b is the relationship curve between the duration of the bending state and the corresponding height during 50 repetitive tests;

[0047] In the figure: 1. Feeding structure; 2. Actuator; 3. Patterned metal patch; 4. Flexible dielectric substrate; 5. Fiber-reinforced active layer; 6. Positive thermal response region; 7. Positive thermal expansion coefficient polymer; 8. Negative thermal expansion coefficient polymer; 9. Fiber; 10. Fish skeleton-style center patch; 11. Metal side strip; 12. Coplanar waveguide section; 13. Mode matching section; 14. Periodic structure section; 15. Detailed Implementation

[0048] To clearly and completely describe the technical solution and its specific working process of the present invention, the specific embodiments of the present invention are as follows, in conjunction with the accompanying drawings:

[0049] Example 1

[0050] like Figure 1As shown, this embodiment provides a bistable tunable pseudosurface plasmonic waveguide for terahertz three-dimensional link interconnection. The waveguide, from top to bottom, includes a patterned metal patch 3, a flexible dielectric substrate 4, and a fiber-reinforced active layer 5. The patterned metal patch 3 consists of a fishbone-shaped central patch 11 and surrounding metal sidebands 12. The fishbone-shaped central patch 11 has a periodic structure with a uniform center and gradually changing ends. The fiber-reinforced active layer 5 is located below the uniform central section of the fishbone-shaped central patch 11. The fiber-reinforced active layer 5 includes a positive thermal response region 6 and a negative thermal response region 7. The positive thermal response region 6 is formed by positive thermal expansion. The waveguide is composed of a polymer with a negative thermal expansion coefficient 8 and a fiber 10. The negative thermal response region 7 is composed of a polymer with a negative thermal expansion coefficient 9 and a fiber 10. The fiber 10 is uniformly laid in the fiber-reinforced active layer 5. The patterned metal patch 3 at both ends of the waveguide and the flexible dielectric substrate 4 constitute the feeding structure 1. The patterned metal patch 3, the flexible dielectric substrate 4 and the fiber-reinforced active layer 5 in the middle section of the waveguide constitute the actuator 2. The left side of the actuator 2 is aligned and fixedly connected to the right side of the feeding structure 1 at the input end as the bending start end. The right side is aligned and non-fixedly connected to the left side of the feeding structure 1 at the output end as the free end. Different interconnection heights are achieved as the actuator 2 bends. In this system, the terahertz signal enters through the feed structure 1 at the input end and is coupled to the actuator 2. Under no-excitation conditions, the actuator 2 is in a horizontal state, and the signal is output from the feed structure 1 at the output end. Under photothermal excitation conditions (such as a 250W infrared heating lamp, a high-power quantum cascade laser, etc.), the positive thermal response region 6 bends in the positive curvature direction, and the negative thermal response region 7 bends in the negative curvature direction. The resulting S-shaped bending shape allows the free end of the actuator 2 to form surface contact with the feed structures 1 at different height levels at the output end. The minimum contact area between the actuator 2 and the feed structure 1 is... This enables dynamic interconnection with ultra-broadband and low loss.

[0051] In this embodiment, the main bone width of the fish skeleton-style central patch 11 of the patterned metal patch 3 is... The skeletal cycle is The width of the lateral bone is The length of the coplanar waveguide segment 13 is The length of the lateral bone is The distance between the metal side strip 12 and the metal side strip 12 is The length of the pattern matching segment 14 is The length of the lateral branch is determined by the end side. Gradual transition to center The distance between the metal side strip 12 and the end side Gradual transition to center The length of the periodic structure segment 15 is The length of the lateral bone is The distance between the metal side strip 12 and the metal side strip 12 is .

[0052] The thickness of the patterned metal patch 3 is The thickness of the flexible dielectric substrate 4 is The length of the actuator 2 is Width is .

[0053] The thickness of the fiber-reinforced active layer 5 is The length ratio of the positive thermal response zone 6 to the negative thermal response zone 7 is 4, and the fiber 10 layup density is... .

[0054] In this embodiment, the patterned metal patch 3 includes, along the signal transmission direction: a coplanar waveguide segment 13 at the input end, a mode matching segment 14 adjacent to the coplanar waveguide segment 13 at the input end, a periodic structure segment 15 in the middle, a mode matching segment 14 at the output end, and a coplanar waveguide segment 13 adjacent to the mode matching segment 14 at the output end; wherein, the periodic structure segment 15 is located in the middle uniform segment of the fishbone-shaped center patch 11;

[0055] The polymer 8 with a positive coefficient of thermal expansion is selected from polydimethylsiloxane or thermoplastic polyurethane elastomer; the polymer 9 with a negative coefficient of thermal expansion is selected from liquid crystal elastomer or liquid crystal polymer network; the fiber 10 is selected from polyimide fiber or aramid fiber. The high stiffness of the fiber 10 extends the effective relaxation time by increasing the energy barrier of the molecular chain relaxation of the polymer 8 with a positive coefficient of thermal expansion and the polymer 9 with a negative coefficient of thermal expansion, thereby realizing the steady-state bending state of the actuator 2.

[0056] The waveguide operates in the frequency band of 31.56~127.71 GHz, corresponding to a center frequency wavelength of... .

[0057] Example 2

[0058] This embodiment provides a method for fabricating a bistable tunable pseudosurface plasmonic waveguide for terahertz three-dimensional link interconnection. Its structural dimensions and operating frequency band are the same as those in Embodiment 1. The specific steps are as follows:

[0059] Step 1: Fabrication of surface waveguide structure:

[0060] First, to facilitate the fabrication of the PI flexible dielectric substrate 4, a silicon wafer was selected as a temporary substrate, and approximately [amount missing] was drawn up using a dropper. The PI solution was uniformly dropped onto the silicon wafer surface and then spin-coated using a spin coater. After spin coating, the sample was placed on a hot plate for curing. The thickness before and after PI plating was measured using a micrometer to confirm the thickness. Repeat the above process 3 times to obtain a thickness of 4. PI flexible dielectric substrate; wherein, the spin coater speed and time are set as follows: ,back The heating temperature and time of the hot plate are set sequentially as follows: ,Again ,Then Finally, cool to room temperature. The total curing time is approximately .

[0061] Then, the plated A thick PI silicon wafer is fixed on a sample tray and fed into the magnetron sputtering chamber. The chamber is then evacuated; a mechanical pump is used to first evacuate the chamber to a vacuum level of [missing value]. Next, turn on the molecular pump until the chamber vacuum level is [value missing]. Turn on the ionization gauge and wait until the vacuum level reaches the specified value. When the ionization gauge is closed, the chamber is filled with... Argon gas, turn on the DC channel power of the selected target material (aluminum metal) ( (), and open the target baffle, set the sample rotation speed to Open the sample baffle, and the process takes about half an hour. Aluminum coating, i.e., unpatterned metal patch 3. After completing the above steps, close the argon gas channel, vent the chamber, and remove the sample after the internal and external gas pressures have balanced. Apply photoresist. Evenly drop the coating onto the surface of the sample with the metal film deposited, covering 2 / 3 of the sample area. Spin coat using a spin coater and heat on a hot plate. Curing; wherein, the spin coater speed and time are set first. ,back .

[0062] Next, the photomasks corresponding to the patterned metal patches 3 of the feed structure 1 and actuator 2 are sequentially mounted on the photomask holder of the lithography machine. The photoresist-coated sample is placed on the sample tray, leveled, and the photomask and sample are clamped together for exposure. The exposure time is... After exposure, place the sample in the developer solution. Medium development, development time is approximately When the exposed area is developed, the sample is cleaned with pure water and dried with nitrogen. Then it is exposed under white light and the morphology of the photolithography structure is observed under a microscope, thus completing the patterning of the metal patch 3 of the power supply structure 1 and the actuator 2.

[0063] Finally, the sample was immersed in the aluminum stripping solution and waited for approximately... It was later observed that the aluminum metal in the area not protected by the photolithography machine was etched away. The sample was cleaned with pure water, dried, and then the remaining photoresist on the structure was cleaned with acetone. The acetone was then cleaned with isopropanol. Finally, the sample was cleaned with pure water and completely peeled off from the silicon wafer, resulting in a power supply structure 1 and actuator 2 with only a single-layer flexible dielectric substrate 4.

[0064] Step 2: Fabrication of the bistable actuator:

[0065] In this embodiment, polydimethylsiloxane (PDMS) is selected as the polymer with a positive coefficient of thermal expansion (8), liquid crystal elastomer (LCE) is selected as the polymer with a negative coefficient of thermal expansion (9), and polyimide (PI) fiber is selected as the fiber (10). The polyimide (PI) fiber (10) is uniformly laid in a rectangular mold; wherein the laying density is... The mold is made of polytetrafluoroethylene and has dimensions of 60×40×0.1.

[0066] Polydimethylsiloxane (PDMS) was taken as the main agent, and then curing agent and carbon nanotubes (CNTS) were added sequentially to obtain a mixed solution. After stirring evenly, the mixture was placed in a centrifuge to remove air bubbles. The solution was then poured into a mold in which polyimide (PI) fibers 10 were evenly laid to form a film. Curing in an oven The thickness was then obtained as Fiber-reinforced PDMS film; wherein the mass ratio of polydimethylsiloxane main agent (PDMS), curing agent and carbon nanotubes (CNTS) is 10:1:0.22; the centrifuge speed is set to The time is set to .

[0067] Liquid crystal molecules are dissolved in an organic solvent, and then a photoinitiator, spacer, crosslinking agent, and catalyst are added to obtain a mixed solution. After stirring evenly, the mixture is poured into a mold in which polyimide (PI) fibers are uniformly laid to form a film, which is then crosslinked at room temperature. Then Heating in a vacuum drying oven The thickness is obtained The fiber-reinforced LCE film contains a liquid crystal molecule of 1,4-bis[4-(3-acryloyloxypropoxy)benzoic acid]-2-toluene, an organic solvent of toluene, a photoinitiator of HMHEAP (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone), a spacer of DODT (3,6-dioxa-1,8-octanedithiol), a crosslinking agent of PETMP (pentaerythritol tetrakis(3-mercaptopropionic acid) ester), and a catalyst of a mixture of DPA (di-n-propylamine) and toluene at a mass ratio of 2:98. The mass ratio of the liquid crystal molecule, organic solvent, photoinitiator, spacer, crosslinking agent, and catalyst is 4:1.6:0.024:0.84:0.36:0.56.

[0068] Step 3: Assemble the 3D link interconnect waveguide:

[0069] The fiber-reinforced PDMS film and fiber-reinforced LCE film are cut and used as positive thermal response region 6 and negative thermal response region 7, respectively. They are placed horizontally without gaps in the direction perpendicular to the fiber 10 with the same width as the actuator 2 and a length ratio of 4, forming a fiber-reinforced active layer 5 and uniformly coated with liquid silicone sealant on its surface.

[0070] like Figure 2 As shown, the actuator 2, which has only a single layer of flexible dielectric substrate 4, is placed on liquid silicone adhesive in a direction perpendicular to the fiber 10, forming a flat, bubble-free and fully bonded three-layer structure, which consists of a patterned metal patch 3, a PI flexible dielectric substrate 4, and a fiber-reinforced active layer 5.

[0071] The input power supply structure 1, actuator 2, and output power supply structure 1 are adhered to the same substrate and the metal patch 3 is located on the same plane. The left side of actuator 2 serves as the bending start end and is fixedly connected to the right side of the input power supply structure 1, while the right side serves as the free end and is not fixedly connected to the left side of the output power supply structure 1. Different interconnection heights are achieved as actuator 2 bends.

[0072] High-power light sources (such as 250W infrared heating lamps, high-power quantum cascade lasers, etc.) are used as photothermal excitation for actuator 2.

[0073] Example 3

[0074] This embodiment simulates the bistable tunable pseudosurface plasmonic waveguide structure for terahertz three-dimensional link interconnection in Embodiment 2. The main performance indicators are selected as S-parameters to characterize the insertion loss, return loss and operating bandwidth of the waveguide structure.

[0075] like Figure 3As shown in (a), three power supply structures 1 are taken. The power supply structure 1 at the input end, the actuator 2, and the power supply structure 1 at the first height level output end are adhered to the same substrate and the metal patch 3 is located on the same plane. The left side of the actuator 2 serves as the bending start end and is fixedly connected to the right side of the power supply structure 1 at the input end. The right side serves as the free end and is not fixedly connected to the left side of the power supply structure 1 at the output end. The power supply structure 1 at the output end includes two layers, namely the power supply structure at the first height level output end and the power supply structure at the second height level output end, which are placed at different height positions to achieve different interconnection heights as the actuator 2 bends. The power supply structure at the second height level output end and the power supply structure at the first height level output end are symmetrical about the xoy plane and are a certain distance apart in the z-axis direction. The power supply structure at the input end serves as the signal input end, the power supply structure at the first height level output end serves as the signal output end of the first height level in three-dimensional space, and the power supply structure at the second height level output end serves as the signal output end of the second height level in three-dimensional space.

[0076] Under natural conditions, actuator 2 is in a horizontal state. The terahertz signal enters and is coupled to actuator 2 through the feed structure 1 at the input end. Its free end provides the interconnection height of the first height level in three-dimensional space. The signal is output from the feed structure 1 at the output end of the first height level.

[0077] like Figure 3 As shown in (b), under photothermal excitation conditions, the flexible dielectric substrate 4 of actuator 2 has a low coefficient of thermal expansion, while the fiber-reinforced active layer 5 has a high coefficient of thermal expansion. Both will elongate to different degrees under the same temperature change, thus bending in the z-axis direction, providing the free end of actuator 2 with an interconnection height for the second height level in three-dimensional space. The fiber-reinforced PDMS film has a positive coefficient of thermal expansion, therefore the positive thermal response region 6 bends in the positive curvature direction on one side, while the fiber-reinforced LCE film has a negative coefficient of thermal expansion, therefore the negative thermal response region 7 bends in the negative curvature direction on one side. The resulting S-shaped bending shape allows actuator 2 to form at least... The surface contact enables low-loss signal output from the feed structure 1 at the output end of the second height level.

[0078] like Figure 4 As shown in (a), actuator 2 is in a horizontal state, and the signal output from the power supply structure 1 at the first height level has a corresponding 3dB bandwidth of... S21 is approximately S31 is approximately The return loss is approximately This indicates that most of the energy is transmitted to the first-level structure in three-dimensional space through the surface waveguide structure, while a small portion of the energy is lost and cannot be transmitted to the second-level structure.

[0079] like Figure 4 As shown in (b), when actuator 2 is in a bent state, the 3dB bandwidth corresponding to the signal output from the power supply structure 1 at the second height level output terminal is... S31 is approximately S21 The return loss is approximately This indicates that most of the energy is transmitted to the second-level structure in three-dimensional space through the surface waveguide structure, while a small portion of the energy is lost and cannot be transmitted to the first-level structure. In summary, the surface waveguide structure of this invention utilizes different excitation conditions to control the signal output from different levels, with an operating frequency band of [frequency band missing]. (Taking 16QAM modulation as an example, the maximum supported data transmission rate is 384.6Gbps), and the relative bandwidth is... Insertion loss is lower than Return loss is lower than It can realize three-dimensional ultra-wideband low-loss dynamic interconnection for terahertz chips and support high-speed data transmission.

[0080] Example 4

[0081] This embodiment verifies that the actuator 2, based on a bistable tunable pseudosurface plasmonic waveguide structure for terahertz three-dimensional link interconnection, achieves bistable characteristics through fiber layup. In this embodiment, the patterned metal patch 3 of the actuator 2 uses 100 periodic structural segments 15, and the thickness of the fiber-reinforced active layer 5 is [missing information]. The length ratio of the positive thermal response zone 6 to the negative thermal response zone 7 is 4, and the fiber layup density is... .

[0082] Furthermore, a 250W infrared heating lamp is used to illuminate the metal patch 3 of the actuator 2 for a duration of [duration missing]. The flexible dielectric substrate 4 has a low coefficient of thermal expansion, while the fiber-reinforced active layer 5 has a high coefficient of thermal expansion. Under the same temperature change, the two will elongate to different degrees, thus bending in the z-axis direction, providing a second interconnection height for the free end of the actuator 2. During the period after the light excitation is removed, the PI fiber increases the energy barrier for the relaxation of the polymer molecular chain due to its high stiffness characteristics, and the effective relaxation time is significantly extended, allowing the actuator 2 to remain in a bent state. After overcoming the energy barrier, the actuator 2 slowly transitions from a bent state to a horizontal state in the z-axis direction, and its free end remains at the first interconnection height until the next external photothermal excitation.

[0083] Furthermore, repeat the above operation 50 times. Figure 5 (a) shows the height variation of the free end of actuator 2, with both the maximum and minimum heights remaining relatively stable; Figure 5(b) shows the duration and corresponding height of the bent state; the duration is approximately 4.61 seconds, and the corresponding height is approximately... This embodiment demonstrates that actuator 2 achieves bistable characteristics using fiber layup, which is beneficial for realizing high-efficiency and stable interconnection between chips of different levels.

[0084] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0085] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0086] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A bistable tunable pseudosurface plasmonic waveguide for terahertz three-dimensional link interconnection, characterized in that, Along the signal transmission direction, the two ends are feeding structures (1), and the middle is an actuator (2); the waveguide is composed of patterned metal patches (3), flexible dielectric substrate (4), and fiber-reinforced active layer (5) from top to bottom; the patterned metal patch (3) is composed of a fish skeleton-type central patch (11) and metal side strips (12) around it, the fish skeleton-type central patch (11) is a periodic structure with uniformity in the middle and gradual change at both ends; the fiber-reinforced active layer (5) is located below the uniform middle section of the fish skeleton-type central patch (11); the fiber-reinforced active layer (5) includes a positive thermal response region (6) and a negative thermal response region (7); wherein, the patterned metal patches (3) at both ends of the waveguide and the flexible dielectric... The substrate (4) constitutes the feeding structure (1), and the patterned metal patch (3), flexible dielectric substrate (4) and fiber-reinforced active layer (5) located in the middle section of the waveguide constitute the actuator (2); wherein, the terahertz signal enters from the feeding structure (1) at the input end and is coupled to the actuator (2). Under no excitation conditions, the actuator (2) is in a horizontal state, and the signal is output from the feeding structure (1) at the output end; under photothermal excitation conditions, the positive thermal response region (6) bends in the positive curvature direction, and the negative thermal response region (7) bends in the negative curvature direction. The resulting S-shaped bending shape enables the free end of the actuator (2) to form surface contact with the feeding structure (1) at the output end of different height levels, thereby realizing ultra-wideband low-loss dynamic interconnection.

2. The bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The output terminal's power supply structure includes multiple power supply structures placed at different heights, serving as three-dimensional interconnected output terminals at different heights.

3. The bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The patterned metal patch (3) includes, along the signal transmission direction: a coplanar waveguide segment (13) at the input end, a mode matching segment (14) adjacent to the coplanar waveguide segment (13) at the input end, a periodic structure segment (15) in the middle, a mode matching segment (14) at the output end, and a coplanar waveguide segment (13) adjacent to the mode matching segment (14) at the output end; wherein, the periodic structure segment (15) is located in the middle uniform segment of the fish skeleton center patch (11).

4. A bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The fish skeleton-type central patch (11) has a main bone width of 0.02~0.04λ, a branch bone period of 0.06~0.08λ, and a branch bone width of 0.02~0.04λ. The length of the coplanar waveguide segment (13) is 0.06~0.08λ, the length of the support is 0, and the distance between it and the metal sideband (12) is... ; The length of the pattern matching segment (14) is 0.6~0.8λ, and the length of the lateral branch is from the end side. Gradual transition to center The distance between the metal side strip (12) and the end side is determined by the distance between the end side and the metal side strip (12). Gradual transition to center ; The length of the periodic structural segment (15) is 0.06~0.08λ, and the length of the branch bone is... The distance between the metal side strip (12) and the metal side strip (12) is ; The length of the feed structure (1) is Width is The length of the actuator (2) is Width is ; in, The wavelength corresponds to the center frequency of the operating frequency band.

5. A bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The thickness of the patterned metal patch (3) is The thickness of the flexible dielectric substrate (4) is ; The thickness of the fiber-reinforced active layer (5) is 0.04~0.06λ, and the length ratio of the positive thermal response region (6) to the negative thermal response region (7) is 0.1~10.

6. A bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The positive thermal response zone (6) is composed of a polymer (8) with a positive thermal expansion coefficient and a fiber (10), and the negative thermal response zone (7) is composed of a polymer (9) with a negative thermal expansion coefficient and a fiber (10); the fiber (10) is uniformly laid in the fiber-reinforced active layer (5).

7. A bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The polymer (8) with a positive coefficient of thermal expansion is selected from polydimethylsiloxane or thermoplastic polyurethane elastomer; the polymer (9) with a negative coefficient of thermal expansion is selected from liquid crystal elastomer or liquid crystal polymer network; the fiber (10) is selected from polyimide fiber or aramid fiber, with a laying density of 3~8 fibers / cm.

8. A bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The contact area between the actuator (2) and the power supply structure (1) at the output end is [area missing]. The bending height of the actuator (2) under photothermal excitation is 0.25~5λ, and the steady-state holding time is 1~8s.

9. A bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in claim 1, characterized in that, The waveguide operates in the frequency band of 31.56~127.71 GHz, with a relative bandwidth of up to 120%, insertion loss of less than 1.5 dB, return loss of less than -15 dB, and steady-state sustaining time of up to [missing information]. .

10. A method for fabricating a bistable tunable pseudosurface plasmon waveguide for terahertz three-dimensional link interconnection as described in any one of claims 1-9, characterized in that, Specifically, the steps include the following: S1. Fabrication of waveguide main structure: A metal layer is deposited on a flexible dielectric substrate, and a patterned metal patch is formed by a subtractive manufacturing process. The patterned metal patch includes a fishbone-shaped center patch and metal side strips. The patterned metal patch includes, along the signal transmission direction: coplanar waveguide segments at both ends, mode matching segments adjacent to the coplanar waveguide segments, and periodic structure segments in the middle; S2. Preparation of the fiber-reinforced active layer: The fiber is combined with a polymer with a positive thermal expansion coefficient to form a positive thermal response composite film; the fiber is combined with a polymer with a negative thermal expansion coefficient to form a negative thermal response composite film; the positive thermal response composite film and the negative thermal response composite film are spliced ​​together to form a fiber-reinforced active layer containing a positive thermal response region and a negative thermal response region. S3. Integration of the actuator: The fiber-reinforced active layer obtained in step S2 is bonded to the lower surface of the flexible dielectric substrate corresponding to the middle section of the waveguide in step S1, so that the fiber-reinforced active layer is located directly below the periodic structure section in the middle of the patterned metal patch, thereby forming an actuator. S4. Overall assembly: Fix the structure obtained in step S3 onto the carrier substrate to complete the integration of the waveguide.

Images