A microstructure-based impedance matching traveling wave electrode on a barium titanate thin film platform

Abstract

This invention discloses a microstructure-based impedance matching traveling-wave electrode on a thin-film barium titanate platform, belonging to the field of high-speed electro-optic modulator technology. Addressing the problem that the high dielectric constant of thin-film barium titanate materials causes a significant deviation of the characteristic impedance of traditional traveling-wave electrodes from 50Ω, this invention introduces a periodically arranged microstructure into the GSG-type electrode structure: double-layer T-type capacitor loads are placed on both sides of the signal electrode, and parasitic capacitance is suppressed through a double-layer metal layer series structure; a rectangular inductive load is placed between adjacent double-layer T-type capacitor loads to improve distributed inductance; a T-type capacitor load is placed on the side of the ground electrode closest to the signal electrode. Through the coordinated design of the signal electrode backbone width, electrode gap, double-layer T-type capacitor loads, T-type capacitor loads, and rectangular inductive loads, the characteristic impedance of the traveling-wave electrode is matched to 50Ω. Simulation results show that the impedance of this invention approaches 50Ω in the 0-120GHz range, with a voltage standing wave ratio (VSWR) of less than 1.1. 11 With a impedance below -22.3 dB and a lower refractive index compared to traditional electrodes, speed matching is easily achieved. This invention solves the impedance matching problem on high dielectric constant material platforms and has promising applications in optical communication, optical interconnection, and optical computing.

Description

Technical Field

[0001] This invention belongs to the field of integrated photonics technology, specifically relating to a microstructure-based impedance matching traveling wave electrode on a thin-film barium titanate platform, which is suitable for electro-optic modulators in applications such as high-speed optical communication, optical interconnection, and optical computing. Background Technology

[0002] With the rapid development of emerging industries such as cloud computing, big data, and artificial intelligence, the demand for bandwidth and data transmission speeds is increasing daily. Given the bandwidth and power consumption bottlenecks encountered by traditional electrical interconnects, optical interconnects, with their high bandwidth, low latency, and anti-interference capabilities, are gradually becoming a key technology for overcoming these bottlenecks. Integrated photonics integrates miniature optical components onto chips, achieving high-speed, low-power optical signal processing and transmission while maintaining a compact structure. As a core device in integrated photonic links, the electro-optic modulator loads high-speed electrical signals onto optical carriers, completing the signal conversion from the electrical domain to the optical domain. Its performance directly determines the transmission capability of the entire integrated photonic system.

[0003] In the design of high-speed electro-optic modulators, traveling-wave electrode structures have become the mainstream solution for achieving higher frequency responses. This structure typically has a length much larger than the wavelength of the microwave signal. The optical wave and microwave signal propagate and interact together in the waveguide and traveling-wave electrode, respectively. This distributed interaction, compared to lumped electrodes, overcomes the bandwidth limitation imposed by the RC charging and discharging time constant, thus achieving modulation bandwidths on the order of hundreds of GHz. A high-performance high-speed electro-optic modulator usually meets three conditions: first, the microwave refractive index matches the optical group refractive index, i.e., velocity matching; second, the characteristic impedance of the traveling-wave electrode matches the impedance of the driver source and the terminal load; and third, the traveling-wave electrode has low microwave loss. Among these, impedance matching is particularly important. If the characteristic impedance of the electrode does not match the standard impedance of the driver source or microwave test system (typically 50Ω), the high-speed electrical signal will be severely reflected at the electrode input, preventing most of the power from entering the modulation region to effectively modulate the optical carrier. Furthermore, severe reflection can easily damage the driver source. Simultaneously, this mismatch can also cause microwave reflections within the electrode, forming standing waves, resulting in reduced modulation bandwidth and degraded signal-to-noise ratio.

[0004] On traditional silicon-based or lithium niobate platforms, due to the relatively low dielectric constant of the materials, which remains largely unchanged with microwave frequency, velocity matching and 50Ω impedance matching can be achieved relatively easily simultaneously by optimizing electrode geometry or substrate materials. However, as integrated photonics advances towards higher integration density and higher energy efficiency, the emergence of novel high electro-optic material platforms such as thin-film barium titanate has brought new impetus to the development of integrated photonics. Barium titanate materials possess extremely high electro-optic coefficients, which can significantly reduce the driving voltage of electro-optic devices and shrink device size. However, its dielectric constant is extremely high, typically ranging from hundreds to thousands, and varies drastically with microwave frequency, posing new challenges to microwave signal transmission. On thin-film barium titanate platforms, the high dielectric constant strongly confines microwave energy within the material, resulting in a characteristic impedance of the electrodes far below 50Ω, typically only around 20-30Ω, and the microwave refractive index is much higher than that of light waves. Traditional traveling-wave electrode design methods can no longer simultaneously achieve velocity matching and impedance matching, forming a key technical bottleneck restricting the performance of barium titanate high-speed modulators.

[0005] Therefore, how to design a traveling wave electrode structure that can meet impedance matching requirements and also take into account modulation efficiency and speed matching under the background of high dielectric constant of thin film barium titanate platform has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] The present invention aims to solve the technical problems existing in the prior art and provides a microstructure-based impedance matching traveling wave electrode on a thin-film barium titanate platform, which can complete the matching of the 50Ω impedance of a standard microwave test system or driving source, while its microwave refractive index is not improved compared with the traditional coplanar waveguide electrode, which facilitates speed matching.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A microstructure-based impedance matching traveling-wave electrode includes three parallel gold electrodes forming a ground electrode-signal electrode-ground electrode structure, with the traveling-wave electrode disposed on a barium titanate material platform. The signal electrode has a main section with a first width. A first gap exists between the signal electrode and the ground electrode. Periodically arranged double-layer T-type capacitive loads are connected to both sides of the signal electrode, and a rectangular inductive load is disposed between adjacent double-layer T-type capacitive loads. A periodically arranged T-type capacitive load is connected to the side of the ground electrode closest to the signal electrode. Through the coordinated design of the first width, the first gap, the double-layer T-type capacitive loads, the T-type capacitive loads, and the rectangular inductive loads, the characteristic impedance of the traveling-wave electrode is matched to 50Ω.

[0008] According to transmission line theory, the performance of a traveling wave electrode is determined by its distributed capacitance (C), distributed inductance (L), distributed resistance (R), and distributed reactance (G). At higher microwave frequencies, the characteristic impedance of the traveling wave electrode is mainly determined by its distributed inductance and distributed capacitance, and its expression is: Barium titanate films have a high dielectric constant, typically ranging from several hundred to several thousand, and this constant varies drastically with frequency. This high dielectric constant results in a very strong ability to store electromagnetic energy, thus their characteristic impedance is far less than 50Ω, typically around 20-30Ω. This invention achieves impedance matching by introducing microstructures to alter the distributed inductance and capacitance of the traveling wave electrodes.

[0009] As a preferred technical solution, the double-layer T-shaped capacitive load includes an outer metal plate and an inner metal plate, which are connected in series to suppress parasitic capacitance. From the series capacitance formula 1 / C = 1 / C1 + 1 / C2, it can be seen that the total capacitance of the two series capacitors will be less than the smallest of the two capacitors. This invention reduces the capacitance represented by the distance between the outer and inner metal plates by making them of unequal length, thereby increasing the gap between the inner metal plate and the signal electrode, and thus reducing the overall series capacitance.

[0010] As a preferred technical solution, the width of the outer metal plate is w 1. The gap between the outer metal plate and the inner metal plate is... w 2. The width of the inner metal plate is w 3. The gap between the inner metal plate and the signal electrode is... w 4. The length of the outer metal plate is l 1， The length of the inner metal plate is l 2. The spacing between adjacent double-layer T-type capacitor loads is l 3; By adjusting the above w 1. w 2. w 3. w 4. l 1. l 2. l 3. Change the size of the parasitic capacitance and adjust the characteristic impedance.

[0011] As a preferred technical solution, the width of the rectangular inductive load is w 5, length is l 4. By adjusting the above w 5 and l 4. Change the magnitude of the distributed inductance and adjust the characteristic impedance.

[0012] As a preferred technical solution, the width of the T-shaped capacitor load on one side of the ground electrode is... w 6, length isl 5. The spacing between adjacent T-type capacitor loads is l 3. By adjusting the above w 6. l 5. l 3. Change the characteristic impedance.

[0013] As a preferred technical solution, the width of the main portion of the signal electrode is w signal The gap between the signal electrode and the ground electrode is gap By adjusting the w signal and gap Change the characteristic impedance.

[0014] As a preferred technical solution, the barium titanate material platform comprises a silicon substrate layer, a silicon dioxide layer, a silicon nitride ridge waveguide layer, and a barium titanate planar layer. This invention utilizes the technology published by Daniel Chelladurai et al. in 2025. Nature Materials The image shows a BTO thin film formed by radio frequency sputtering, with Barium titanate and lithium niobate permittivity and Pockelscoefficients from megahertz to sub-terahertz frequencies.

[0015] As a preferred technical solution, the thickness of the silicon nitride ridge waveguide layer is 0.3 μm, the thickness of the barium titanate plate layer is 0.3 μm, and the thickness of the silicon dioxide layer is 4.7 μm.

[0016] As a preferred technical solution, the traveling wave electrode is made of gold and has a thickness of 0.3 μm.

[0017] As a preferred technical solution, the arrangement period of the double-layer T-shaped capacitor load, the T-shaped capacitor load and the rectangular inductor load is 50μm, and the cutoff frequency of the microwave signal corresponding to this period is greater than 1000GHz.

[0018] The impedance matching traveling wave electrode proposed in this invention has the following advantages: 1. Effectively solves the impedance mismatch problem of barium titanate (BTO) materials with high dielectric constants. Addressing the issue of excessively low characteristic impedance in traditional traveling wave electrodes due to the high dielectric constants of BTO materials (hundreds to thousands), this invention introduces inductive and capacitive microstructures to precisely control the distributed inductance and capacitance of the transmission line, successfully raising and matching the characteristic impedance to the standard 50Ω. This fundamentally solves the problem of severe microwave energy reflection (S0) caused by impedance deviation. 11To address the issue of excessively high dielectric constants, this invention ensures that microwave signals can efficiently enter the electrodes for modulation. Based on the next-generation high-performance optoelectronic material—barium titanate—this invention fully leverages its potential for high electro-optic coefficients and high energy efficiency while overcoming the technical bottlenecks caused by its high dielectric constant. This design approach is not only applicable to barium titanate but also provides a feasible solution for electrode design in other high-dielectric-constant material systems, demonstrating significant application value in fields requiring high-performance electro-optic modulation, such as high-speed optical communication, optical interconnects, and optical computing.

[0019] 2. The innovative "double-layer T-shaped" structure balances modulation efficiency and parasitic capacitance suppression. The "double-layer T-shaped" capacitive load used on the signal electrodes is a highlight of the structural design of this invention. On the one hand, it can effectively guide the electric field to the modulation region where the waveguide is located, making the electric field distribution uniform and ensuring high electro-optic modulation efficiency; on the other hand, through the double-layer series structure and non-equal length design, the total distributed capacitance is smaller than that of the single-layer structure, cleverly suppressing the additional parasitic capacitance generated by introducing the T-shaped structure and avoiding the negative impact on impedance matching.

[0020] 3. Introducing inductive loads to actively increase impedance: Rectangular inductive loads are designed between all "T-type" and "double-layer T-type" structures. These structures effectively increase the distributed inductance of the traveling wave electrodes by changing the current path and magnetic field distribution, pushing the electrode impedance from 20-30 Ω towards 50 Ω.

[0021] 4. Facilitates matching of microwave refractive index with optical group refractive index. In high dielectric constant platforms, the microwave refractive index is often greater than the optical group refractive index, leading to difficulties in refractive index matching. Due to the presence of the microstructure, some electromagnetic field energy propagates within the air cladding, and the series capacitor design suppresses the increase of additional capacitance. This allows the traveling wave electrode of this invention to achieve impedance matching without increasing its microwave refractive index compared to traditional coplanar waveguide electrodes, and may even decrease it. The lower microwave refractive index reduces the difficulty of velocity matching with optical waveguides (especially slow optical waveguides), which is beneficial for achieving wider bandwidth modulation.

[0022] 5. Improved signal integrity and modulation quality: By addressing impedance mismatch, this invention significantly reduces microwave reflection and standing wave effects at traveling wave electrodes. This not only allows microwave energy to effectively enter the modulation region but also prevents signal quality degradation caused by reflected waves, thereby improving the signal-to-noise ratio of the modulated signal. In terms of system performance, this translates to optimized eye diagram quality in optical communication, reduced bit error rate, and compliance with the stringent signal integrity requirements of high-speed optical interconnects. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the impedance matching traveling wave electrode structure proposed in this invention.

[0024] Figure 2 This is a cross-sectional view of the material platform where the impedance matching traveling wave electrode is located.

[0025] Figure 3 This is a graph showing the variation of characteristic impedance of an impedance-matched traveling wave electrode and a conventional coplanar waveguide electrode with the same parameters as microwave frequency.

[0026] Figure 4 This is a graph showing the voltage standing wave ratio (VSWR) of the impedance matching electrode and the conventional coplanar waveguide electrode as a function of microwave frequency under a 50Ω port impedance.

[0027] Figure 5 It is the S-type impedance matching electrode and the conventional coplanar waveguide electrode under a 50Ω port impedance. 11 With S 21 A graph showing the variation with microwave frequency.

[0028] Figure 6 This is a graph showing the microwave refractive index of an impedance matching electrode and a conventional coplanar waveguide electrode as a function of microwave frequency under a 50Ω port impedance.

[0029] Figure 7 This is a surface current density diagram of an impedance-matched traveling wave electrode. Detailed Implementation

[0030] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0031] like Figure 1 As shown, this is an embodiment of the impedance matching traveling wave electrode on the thin-film barium titanate platform proposed in this invention, which includes ground electrodes on both sides and a signal electrode in the center, forming a GSG push-pull structure.

[0032] The core of this structure is a periodically arranged microstructure: double-layer T-shaped capacitive loads and rectangular inductive loads are located on both sides of the signal electrode, and a T-shaped capacitive load and a rectangular inductive load are located on one side of the ground electrode. Due to the distribution characteristics of the traveling wave electrodes, these loads are all arranged periodically, with the periodic... p When set to 50μm, the cutoff frequency of the microwave signal corresponding to this period is greater than 1000GHz.

[0033] The structure of the double-layer T-type capacitor load is composed of w 1. w 2. w 3. w 4 and l 1. l 2. l 3. Jointly decided. Among them w 1 represents the width of the outer metal plate, which is set to 8μm in this embodiment; w 2 represents the gap between the outer metal plate and the inner metal plate, which is set to 4μm in this embodiment; w3 represents the width of the inner metal plate, which is set to 10 μm in this embodiment; w 4 represents the gap between the inner metal plate and the signal electrode, which is set to 15 μm in this embodiment; l 1 represents the length of the outer metal plate, set to 40μm; l 2 represents the length of the inner metal plate, set to 45μm; l 3 represents the distance between two adjacent double-layer T-type capacitor loads, set to 45μm.

[0034] The structure of the rectangular inductive load is composed of w 5 and l The fourth factor, the width and length of the rectangle, are crucial. The inductive load significantly impacts the introduced distributed inductance, and therefore its parameters strongly influence the characteristic impedance. In this embodiment, w 5 and l 4 can be adjusted as needed; in this embodiment, it is set to 5μm and 6μm respectively.

[0035] The T-shaped capacitor load structure on one side of the ground electrode is composed of w 6. w 7. l 3 and l The widths of the ground electrodes are determined by the following factors: 5. In this embodiment, they are set to 6.5μm, 15μm, 45μm, and 45μm respectively. w ground In this embodiment, it is set to 80μm to meet the requirements of high-speed probe access.

[0036] Besides the impact of parasitic capacitance and inductance caused by the load on impedance, the width of the signal electrode backbone... w signal and electrode gap gap The effect on characteristic impedance is also significant. This embodiment sets... gap It is 21.5μm. w signal It is 5μm. It should be noted that here... w signal This represents the width of the main trunk at the center of the signal electrode, not the total width of the signal electrode. In contrast, the total width of the signal electrode in a traditional coplanar waveguide electrode should be... The wider the signal electrode, the greater its characteristic impedance.

[0037] like Figure 2 The diagram shows the platform structure used in this embodiment, which is a silicon nitride-barium titanate heterogeneous integration platform on an insulator. The barium titanate platform comprises, from bottom to top, a silicon substrate layer, a silicon dioxide layer, a silicon nitride ridge waveguide layer, and a barium titanate planar layer. The ridge waveguide of this platform is defined by the silicon nitride waveguide, and the barium titanate planar layer provides a strong electro-optic effect for the electro-optic device. The traveling wave electrode is made of gold, and its thickness is...h Au The thickness of the silicon nitride ridge waveguide layer is 0.3 μm. h SiN The thickness of the barium titanate plate layer is 0.3 μm. h BTO The thickness of the silicon dioxide layer is 0.3 μm. h OX Set to 4.7μm.

[0038] Through high-frequency electromagnetic field simulation, the performance indicators of the impedance-matching traveling wave electrode proposed in this invention were obtained. Furthermore, to intuitively demonstrate the tuning capability and significance of this invention for the traveling wave electrode impedance, this embodiment simulated a traditional coplanar waveguide electrode with the same parameters, and the results are compared and presented.

[0039] Figure 3 This demonstrates the characteristic impedance variations of impedance-matched electrodes and conventional coplanar waveguide electrodes within the 0-120 GHz microwave frequency range. It can be seen that the same... gap and w signal Under these conditions, the impedance of a traditional coplanar waveguide electrode is only about 25.5Ω, which deviates significantly from the 50Ω impedance of a standard microwave test system or driver source. When the electrode structure proposed in this invention is used, the characteristic impedance of the traveling wave electrode approaches 50Ω. Considering process tolerances and process level, the minimum variation in electrode structure parameters is 0.5μm. With precise adjustment of the structure parameters, even better matching results can be obtained.

[0040] Figure 4 The voltage standing wave ratios (VSWRs) of two types of traveling-wave electrodes are demonstrated, with the port excitation impedance set to 50Ω to simulate a real 50Ω test system. It can be seen that in the 0-120GHz microwave frequency range, traditional coplanar waveguide electrodes exhibit a large VSWR, reaching up to 2.4, due to impedance mismatch. This strong reflection causes a significant deterioration in signal quality and introduces substantial noise into modulation. Conversely, the impedance-matched traveling-wave electrode structure proposed in this invention, with its characteristic impedance close to 50Ω, has a VSWR generally less than 1.1 across the entire frequency range, exhibiting minimal reflection and meeting engineering application standards. Furthermore, the VSWR also confirms that the impedance of the proposed impedance-matched traveling-wave electrode is close to 50Ω.

[0041] Figure 5 This demonstrates the S-type of conventional coplanar waveguide electrodes and impedance matching electrodes. 11 and S 21 Parameters. Traditional coplanar waveguide electrodes suffer from severe impedance mismatch, and their S... 11 Extremely high, with a maximum of -7.65 dB. Conversely, the S of the impedance matching electrode... 11 Less than -22.3dB across the entire frequency range, extremely low S11 Impedance matching is beneficial for efficient energy transfer and improving the signal-to-noise ratio of modulated signals. 21 The decrease in microwave loss is greater because the introduction of microstructures makes the traveling wave electrode less smooth, more energy will be transmitted in the air, and there are more abrupt transitions between the air and the metal interface, thus increasing microwave loss.

[0042] Figure 6 The microwave refractive indexes of the two electrodes are shown. Due to the suppression of parasitic capacitance by the double-layer T-type load, the rectangular inductive load can achieve impedance matching without introducing too much inductance. Meanwhile, increasing both capacitance and inductance leads to an increase in microwave refractive index, so the microwave refractive index is not significantly improved. Conversely, because more electric field energy is in the air, its microwave refractive index is slightly lower than that of the traditional coplanar waveguide electrode, which is due to the sacrifice of some S... 21 One of the improvements achieved is that a 1μm wide silicon nitride-barium titanate waveguide has a TE0 mode group refractive index of approximately 2.25. However, the extremely high dielectric constant of barium titanate results in a persistently high microwave refractive index, making it very difficult to match. Existing solutions typically employ slow waveguides, whose group refractive index can reach around 6. Therefore, the microwave refractive index of this electrode can be matched with the group refractive index of the slow waveguide.

[0043] Figure 7 The surface current density of the impedance matching traveling wave electrode proposed in this invention at 120 GHz is demonstrated. The surface current density is highest in the main body of the signal electrode, while most of the current is concentrated at the edges of the signal and ground electrodes, which is related to the skin effect. The introduction of the microstructure will cause more electromagnetic energy to enter the air gap, thereby increasing the loss, but it will reduce the microwave refractive index, making it easier to match, and simultaneously increasing the impedance to about 50 Ω. It is worth noting that in this embodiment... gap At a depth of 21.5 μm, the modulation efficiency is relatively low, but by adjusting the parameters of all loads, better structural parameters that balance modulation efficiency can be obtained. Furthermore, the structure in this embodiment can serve as an interface for the traveling wave electrode, and can be connected to the traveling wave electrode structure that performs the modulation function with extremely low reflection through impedance tuning.

[0044] In summary, this invention proposes a microstructure-based impedance-matching traveling-wave electrode for the high-dielectric-constant barium titanate thin-film platform. Through the synergistic design of a double-layer T-type capacitive load on the signal electrode, and a T-type load and rectangular inductive load on the ground electrode, the electric field is effectively guided to the modulation region while parasitic capacitance is suppressed using a series structure, and the characteristic impedance is improved from 25.5Ω in the traditional structure to 50Ω. Simulation results show that the electrode has a voltage standing wave ratio (VSWR) of less than 1.1 in the 0-120GHz range. 11With a impedance below -22.3 dB and a low microwave refractive index, it is easy to achieve velocity matching with slow optical waveguides. This invention provides a practical solution for high-speed electro-optic modulators in high-dielectric-constant material systems, combining impedance matching and signal integrity.

[0045] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A microstructure-based impedance matching traveling wave electrode on a thin-film barium titanate platform, comprising three parallel gold electrodes forming a ground electrode-signal electrode-ground electrode structure, characterized in that, The traveling wave electrode is disposed on a barium titanate material platform; a periodically arranged double-layer T-shaped capacitor load is connected to both sides of the signal electrode, and a rectangular inductive load is disposed between adjacent double-layer T-shaped capacitor loads; a periodically arranged T-shaped capacitor load is connected to the side of the ground electrode closest to the signal electrode; through the coordinated design of the double-layer T-shaped capacitor load, the T-shaped capacitor load and the rectangular inductive load, the characteristic impedance of the traveling wave electrode is matched to 50Ω.

2. The impedance matching traveling wave electrode according to claim 1, characterized in that, The double-layer T-shaped capacitive load includes an outer metal plate and an inner metal plate, which suppress parasitic capacitance through a series structure.

3. The impedance matching traveling wave electrode according to claim 2, characterized in that, The width of the outer metal plate is w 1. The gap between the outer metal plate and the inner metal plate is... w 2. The width of the inner metal plate is w 3. The gap between the inner metal plate and the signal electrode is... w 4. The length of the outer metal plate is l 1. The length of the inner metal plate is l 2. The spacing between two adjacent double-layer T-type capacitor loads is l 3; By adjusting the above w 1. w 2. w 3. w 4. l 1. l 2. l 3. Change the size of the parasitic capacitance and adjust the characteristic impedance.

4. The impedance matching traveling wave electrode according to claim 1, characterized in that, The width of the rectangular inductive load is w 5, length is l 4. By adjusting the above w 5 and l 4. Change the magnitude of the distributed inductance and adjust the characteristic impedance.

5. The impedance matching traveling wave electrode according to claim 1, characterized in that, The width of the T-type capacitor load on one side of the ground electrode is w 6, length is l 5. The spacing between two adjacent T-type capacitor loads is the same as the spacing between two adjacent double-layer T-type capacitor loads. l 3; By adjusting w 6. l 5. l 3. Change the characteristic impedance.

6. The impedance matching traveling wave electrode based on a microstructure according to claim 1, characterized in that, The width of the main portion of the signal electrode is... w signal The gap between the signal electrode and the ground electrode is gap By adjusting the w signal and gap Change the characteristic impedance.

7. The impedance matching traveling wave electrode according to claim 1, characterized in that, The barium titanate material platform is a silicon nitride-barium titanate heterogeneous integration platform on an insulator, comprising a silicon substrate layer, a silicon dioxide layer, a silicon nitride ridge waveguide layer, and a barium titanate plate layer.

8. The impedance matching traveling wave electrode according to claim 7, characterized in that, The thickness of the silicon nitride ridge waveguide layer and the barium titanate plate layer is 0.3 μm, and the thickness of the silicon dioxide layer is 4.7 μm.

9. The impedance matching traveling wave electrode according to claim 1, characterized in that, The traveling wave electrode is made of gold, and the gold layer thickness is 0.3 μm.

10. The impedance matching traveling wave electrode according to any one of claims 1 to 9, characterized in that, The arrangement period of the double-layer T-type capacitor load, the T-type capacitor load, and the rectangular inductive load is 50μm.

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