Electro-optical modulator, optical module and optical chip

Abstract

Disclosed in the embodiments of the present application are an electro-optical modulator, an optical module and an optical chip. Electrodes are distributed on two sides of each waveguide of the electro-optical modulator, wherein each electrode comprises a main electrode that extends in the same direction as the waveguide and auxiliary electrodes that extend from the main electrode towards the waveguide. In the extension direction of waveguides, the electro-optical modulator is divided into a plurality of modulation regions, and structural characteristics of auxiliary electrodes in adjacent modulation regions are different, so that radio frequency characteristic parameters of different modulation regions are different. Thus, the radio frequency characteristic parameters of the modulation regions can be flexibly configured according to actual conditions to meet the requirements of radio frequency matching, thereby helping to increase bandwidth and reduce power consumption, reducing reflections occurring in an electrical signal transmission process, and thus improving the electro-optical modulation performance.

Description

Electro-optical modulator, optical module and optical chip

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on December 14, 2023, with application number 202311726820.4 and invention name “An electro-optical modulator, optical module and optical chip”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of electro-optical modulation, and in particular to an electro-optical modulator, an optical module and an optical chip. Background Art

[0003] In optical communication systems, optical modules are a crucial component, primarily performing the conversion between electricity and light. As optical modules evolve toward higher speeds, lower costs, and higher levels of integration, on-chip integration technologies, exemplified by silicon photonics, have emerged and matured. Among these technologies, electro-optical modulators are key components, performing the conversion from electrical to optical signals.

[0004] As demand for communication capacity continues to increase, the transmission rate of communication systems is also increasing. Therefore, the collaborative design of electrical integrated circuits (EICs) and optical integrated circuits (PICs) is gaining increasing attention and becoming a key means of improving system transmission performance. Currently, in architectures that combine the EIC's power driver and the PIC's electro-optical modulator, it's difficult to simultaneously achieve RF parameter matching, high output swing, high bandwidth, and low power consumption, hindering improvements in electro-optical modulation performance.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide an electro-optical modulator, an optical module, and an optical chip, which facilitate flexible configuration of the radio frequency characteristic parameters of each modulation zone within the electro-optical modulator according to actual conditions to meet radio frequency matching requirements, thereby facilitating improved bandwidth and reduced power consumption, reducing reflections during electrical signal transmission, and thus improving electro-optical modulation performance.

[0007] In a first aspect, an embodiment of the present application provides an electro-optical modulator. The electro-optical modulator includes: a first waveguide, a second waveguide, and a plurality of electrodes. The first waveguide and the second waveguide are used to transmit light, and the plurality of electrodes are used to transmit electrical signals. For example, the electrodes drive the waveguides by loading high-speed radio frequency signals. The plurality of electrodes are distributed on both sides of the first waveguide and on both sides of the second waveguide along a first direction, and each electrode includes a main electrode and a plurality of auxiliary electrodes connected to the main electrode. The first waveguide, the second waveguide, and the main electrode extend in a second direction, and the plurality of auxiliary electrodes are distributed along the second direction, with the first direction being perpendicular to the second direction. The auxiliary electrodes connected to the main electrodes located on both sides of the first waveguide extend toward the first waveguide, and the auxiliary electrodes connected to the main electrodes located on both sides of the second waveguide extend toward the second waveguide. The electro-optical modulator includes a plurality of modulation areas in the second direction, with the first modulation area and the second modulation area being adjacent modulation areas. The structural features of the auxiliary electrodes in the first modulation area are different from the structural features of the auxiliary electrodes in the second modulation area.

[0008] In this embodiment, the structural features of the auxiliary electrodes differ in different modulation zones, resulting in different RF characteristic parameters for each modulation zone. This facilitates flexible configuration of the RF characteristic parameters of each modulation zone based on actual conditions to meet RF matching requirements, thereby increasing bandwidth, reducing power consumption, and minimizing reflections during electrical signal transmission, thereby improving electro-optical modulation performance.

[0009] In some possible embodiments, in a plane including the first direction and the second direction, the cross-section of any auxiliary electrode in the first modulation area is different from the cross-section of any auxiliary electrode in the second modulation area, so that the structure of the auxiliary electrodes in each modulation area can be flexibly designed, expanding the implementation method of the solution.

[0010] In some possible embodiments, the structural characteristics of any auxiliary electrode in the first modulation zone in the first direction are different from the structural characteristics of any auxiliary electrode in the second modulation zone in the first direction, and / or the structural characteristics of any auxiliary electrode in the first modulation zone in the second direction are different from the structural characteristics of any auxiliary electrode in the second modulation zone in the second direction. In other words, the structural characteristics of the auxiliary electrodes in at least one direction parallel and perpendicular to the waveguide extension direction have a significant impact on the RF characteristic parameters of the modulation zone, facilitating flexible configuration of the RF characteristic parameters of each modulation zone based on actual conditions to simultaneously meet the requirements of high bandwidth and RF matching.

[0011] In some possible implementations, each auxiliary electrode includes a first electrode structure extending in a first direction and a second electrode structure extending in a second direction. One end of the first electrode structure is connected to the corresponding main electrode, and the other end of the first electrode structure is connected to the second electrode structure. This implementation provides a T-shaped auxiliary electrode structure, which is beneficial to the modulation performance of the electro-optic modulator.

[0012] In some possible embodiments, the length of the first electrode structure of any auxiliary electrode in the first modulation zone in the first direction is different from the length of the first electrode structure of any auxiliary electrode in the second modulation zone in the first direction, and / or the length of the second electrode structure of any auxiliary electrode in the first modulation zone in the second direction is different from the length of the second electrode structure of any auxiliary electrode in the second modulation zone in the second direction. It should be understood that the length of the first electrode structure of the auxiliary electrode in the first direction and the length of the second electrode structure of the auxiliary electrode in the second direction have a significant impact on the RF characteristic parameters of the modulation zone, making it easier to flexibly configure the RF characteristic parameters of each modulation zone according to actual conditions to simultaneously meet the requirements of high bandwidth and RF matching.

[0013] In some possible embodiments, the first electrode structure of each auxiliary electrode in the same modulation area has the same length in the first direction, and the second electrode structure of each auxiliary electrode in the same modulation area has the same length in the second direction. In the light transmission direction, the lengths of the first electrode structures of the auxiliary electrodes in the multiple modulation areas in the first direction gradually increase, and / or the lengths of the second electrode structures of the auxiliary electrodes in the multiple modulation areas in the second direction gradually increase. This design allows the characteristic impedance of each modulation area along the light transmission direction to gradually decrease, which is beneficial for achieving RF matching.

[0014] In some possible embodiments, the length variation of the first electrode structure of the auxiliary electrodes in each two adjacent modulation zones is the same in the first direction, and / or the length variation of the second electrode structure of the auxiliary electrodes in each two adjacent modulation zones is the same in the second direction. In other words, the variation of the structural features of the auxiliary electrodes in each two consecutive modulation zones remains consistent, which helps reduce reflections caused by electrical signals during transmission, ensures a constant electrical signal transmission speed, and improves modulation performance.

[0015] In some possible embodiments, each auxiliary electrode includes two first electrode structures, and the distance between the two first electrode structures of any auxiliary electrode in the first modulation zone is different from the distance between the two first electrode structures of any auxiliary electrode in the second modulation zone. It should be understood that for an electro-optical material modulator, the length of the first electrode structure of the auxiliary electrode in the first direction and the length of the second electrode structure of the auxiliary electrode in the second direction have a greater impact on the electric field intensity, and thus a greater impact on the modulation effect. Therefore, another auxiliary electrode structure is provided here, considering changing the RF characteristic parameters of the modulation zone by changing the distance between the two first electrode structures of the auxiliary electrode, while ensuring the modulation effect, it is convenient to flexibly configure the RF characteristic parameters of each modulation zone according to actual conditions, so as to simultaneously meet the requirements of high bandwidth and RF matching.

[0016] In some possible embodiments, the distance between the two first electrode structures of each auxiliary electrode in the same modulation zone is the same, and the distance between the two first electrode structures of the auxiliary electrodes of the multiple modulation zones in the direction of light transmission gradually increases, so that the characteristic impedance of each modulation zone along the direction of light transmission gradually becomes smaller, which is conducive to achieving RF matching.

[0017] In some possible implementations, the distance between the two first electrode structures of the auxiliary electrodes in each two adjacent modulation areas changes by the same amount, which is beneficial to reducing reflections formed during the transmission of electrical signals, ensuring that the transmission speed of electrical signals remains unchanged, and improving modulation performance.

[0018] In some possible implementations, the width of the first electrode structure of any auxiliary electrode in the first modulation zone in the second direction is different from the width of the first electrode structure of any auxiliary electrode in the second modulation zone in the second direction, and / or the width of the second electrode structure of any auxiliary electrode in the first modulation zone in the first direction is different from the width of the second electrode structure of any auxiliary electrode in the second modulation zone in the first direction. This implementation provides two additional structural features of the auxiliary electrodes that affect RF characteristic parameters, expanding the implementation methods for configuring RF characteristic parameters for each modulation zone.

[0019] In some possible embodiments, the number of first electrode structures of any auxiliary electrode in the first modulation zone is different from the number of first electrode structures of any auxiliary electrode in the second modulation zone. While ensuring the modulation effect, it is convenient to flexibly configure the RF characteristic parameters of each modulation zone according to actual conditions to simultaneously meet the requirements of high bandwidth and RF matching.

[0020] In some possible embodiments, each auxiliary electrode also includes a third electrode structure extending in the second direction, the third electrode structure is connected to the first electrode structure, and the third electrode structure is located between the second electrode structure and the corresponding main electrode. The length of the third electrode structure of any auxiliary electrode in the first modulation area in the second direction is different from the length of the third electrode structure of any auxiliary electrode in the second modulation area in the second direction, and / or the width of the third electrode structure of any auxiliary electrode in the first modulation area in the first direction is different from the width of the third electrode structure of any auxiliary electrode in the second modulation area in the first direction, and / or the distance between the second electrode structure and the third electrode structure of any auxiliary electrode in the first modulation area is different from the distance between the second electrode structure and the third electrode structure of any auxiliary electrode in the second modulation area. This embodiment provides another auxiliary electrode structure, which enhances the scalability of the present solution. While ensuring the modulation effect, it is convenient to flexibly configure the RF characteristic parameters of each modulation area according to actual conditions to simultaneously meet the requirements of high bandwidth and RF matching.

[0021] In some possible implementations, the spacing between any two adjacent auxiliary electrodes in the first modulation area is different from the spacing between any two adjacent auxiliary electrodes in the second modulation area. In scenarios where there are multiple auxiliary electrodes in the modulation area, the RF characteristic parameters of the modulation area can also be changed by changing the spacing between two adjacent auxiliary electrodes, which has a good practical effect.

[0022] In some possible implementations, the width of the main electrode in the first direction is gradually varied. Changing the width of the main electrode in the first direction can also change the RF characteristic parameters of the modulation zone, increasing the flexibility of this solution. Furthermore, the smoother width transition of the main electrode can more effectively prevent reflections during electrical signal transmission, thereby improving modulation performance.

[0023] In some possible embodiments, the electro-optic modulator further includes a first P-type doped structure, a first N-type doped structure, a second P-type doped structure, and a second N-type doped structure extending along a second direction; the first waveguide includes a first P-type doped region and a first N-type doped region; the second waveguide includes a second P-type doped region and a second N-type doped region; an electrode located on one side of the first waveguide is connected to the first P-type doped region via the first P-type doped structure, an electrode located on the other side of the first waveguide is connected to the first N-type doped region via the first N-type doped structure, an electrode located on one side of the second waveguide is connected to the second P-type doped region via the second P-type doped structure, and an electrode located on the other side of the second waveguide is connected to the second N-type doped region via the second N-type doped structure. This embodiment provides a structure of a silicon optical modulator, expanding the types of electro-optic modulators compatible with this solution.

[0024] In some possible embodiments, the distance between the first P-type doping region and the first N-type doping region in the first modulation region is different from the distance between the first P-type doping region and the first N-type doping region in the second modulation region, and the distance between the second P-type doping region and the second N-type doping region in the first modulation region is different from the distance between the second P-type doping region and the second N-type doping region in the second modulation region. In this embodiment, the structural features of the P-type doping region and the N-type doping region in each modulation region can be adjusted according to actual conditions, which is beneficial for reducing the loss of electrical signals caused by increasing transmission distance, thereby increasing bandwidth while maintaining high modulation efficiency.

[0025] In some possible embodiments, within the plane of the first direction and the second direction, the relative size ratio of the cross-sections of the first P-type doped region and the first N-type doped region in the first modulation zone is different from the relative size ratio of the cross-sections of the first P-type doped region and the first N-type doped region in the second modulation zone, and the relative size ratio of the cross-sections of the second P-type doped region and the second N-type doped region in the first modulation zone is different from the relative size ratio of the cross-sections of the second P-type doped region and the second N-type doped region in the second modulation zone. Another specific implementation method for adjusting the structural features of the P-type doped region and the N-type doped region in each modulation zone is provided in the embodiments, which is beneficial for reducing the loss of electrical signals caused by increasing transmission distance, thereby increasing bandwidth while maintaining high modulation efficiency.

[0026] In some possible embodiments, the doping concentration of the first P-type doping region in the first modulation region is different from the doping concentration of the first P-type doping region in the second modulation region, and / or the doping concentration of the first N-type doping region in the first modulation region is different from the doping concentration of the first N-type doping region in the second modulation region. The doping concentration of the second P-type doping region in the first modulation region is different from the doping concentration of the second P-type doping region in the second modulation region, and / or the doping concentration of the second N-type doping region in the first modulation region is different from the doping concentration of the second N-type doping region in the second modulation region. Another specific implementation method for adjusting the structural characteristics of the P-type doping region and the N-type doping region in each modulation region is provided in the embodiment, which is conducive to reducing the loss of electrical signals caused by increasing the transmission distance, which can both increase the bandwidth and maintain high modulation efficiency.

[0027] In some possible implementations, the multiple electrodes include a first electrode, a second electrode, and a third electrode. The first waveguide is located between the first and second electrodes, the second waveguide is located between the second and third electrodes, the first and third electrodes are grounded, and the second electrode is loaded with an electrical signal. In other words, this implementation utilizes a GSG-type electrode design, which has a good practical effect.

[0028] In some possible implementations, the multiple electrodes include a first electrode, a second electrode, a third electrode, and a fourth electrode. The first waveguide is located between the first and second electrodes, the second waveguide is located between the third and fourth electrodes, the first and fourth electrodes are grounded, and the second and third electrodes are respectively loaded with differential electrical signals. In other words, this implementation utilizes a GSSG-type electrode design, expanding the applicable scenarios of this solution.

[0029] In some possible implementations, the electro-optic modulator further includes a first resistor and a second resistor, the second electrode is connected to the first resistor, and the third electrode is connected to the second resistor.

[0030] In some possible implementations, the plurality of electrodes further includes a fifth electrode, the fifth electrode being located between the second electrode and the third electrode, and the fifth electrode being grounded. In other words, this implementation adopts a GSGSG type electrode design, expanding the scenarios to which this solution can be applied.

[0031] In some possible embodiments, the electro-optic modulator further includes a beam splitting module and a beam combining module, wherein the first waveguide is connected to the beam splitting module and the beam combining module at both ends, and the second waveguide is connected to the beam splitting module and the beam combining module at both ends. The beam splitting module is configured to split input light and transmit the split light to the first waveguide and the second waveguide, respectively. The beam combining module is configured to combine the light transmitted by the first waveguide with the light transmitted by the second waveguide.

[0032] In a second aspect, embodiments of the present application provide an electro-optical modulator. The electro-optical modulator comprises a first waveguide, a second waveguide, and a plurality of electrodes. The first and second waveguides are used to transmit light, and the plurality of electrodes are used to transmit electrical signals. For example, the electrodes drive the waveguides by loading high-speed radio frequency signals. The plurality of electrodes are distributed along a first direction on both sides of the first waveguide and on both sides of the second waveguide. The first waveguide, the second waveguide, and the electrodes extend in a second direction, with the first direction being perpendicular to the second direction. The electro-optic modulator also includes a first P-type doped structure, a first N-type doped structure, a second P-type doped structure, and a second N-type doped structure extending along a second direction. The first waveguide includes a first P-type doped region and a first N-type doped region, and the second waveguide includes a second P-type doped region and a second N-type doped region. An electrode located on one side of the first waveguide is connected to the first P-type doped region via the first P-type doped structure, and an electrode located on the other side of the first waveguide is connected to the first N-type doped region via the first N-type doped structure. An electrode located on one side of the second waveguide is connected to the second P-type doped region via the second P-type doped structure, and an electrode located on the other side of the second waveguide is connected to the second N-type doped region via the second N-type doped structure. Along the second direction, the structural features of the first P-type doped region and / or the first N-type doped region vary, and the structural features of the second P-type doped region and / or the second N-type doped region vary. It should be understood that flexibly adjusting the structural features of the P-type doped region and the N-type doped region based on actual conditions can help reduce electrical signal loss caused by increasing transmission distance, thereby increasing bandwidth while maintaining high modulation efficiency.

[0033] In some possible implementations, in the second direction, the distance between the first P-type doping region and the first N-type doping region varies, and the distance between the second P-type doping region and the second N-type doping region varies.

[0034] In some possible embodiments, within the plane where the first direction and the second direction are located, the relative size ratio of the cross-sections of the first P-type doping region and the first N-type doping region changes along the second direction, and the relative size ratio of the cross-sections of the second P-type doping region and the second N-type doping region changes along the second direction.

[0035] In some possible implementations, in the second direction, the doping concentration of the first P-type doping region varies and / or the doping concentration of the first N-type doping region varies. In the second direction, the doping concentration of the second P-type doping region varies and / or the doping concentration of the second N-type doping region varies.

[0036] On the third aspect, an embodiment of the present application provides an electro-optical modulator. The electro-optical modulator includes: a first waveguide, a second waveguide and a plurality of electrodes. The first waveguide and the second waveguide are used to transmit light, and the plurality of electrodes are used to transmit electrical signals. For example, the electrodes drive the waveguides by loading high-speed radio frequency signals. The plurality of electrodes are distributed on both sides of the first waveguide and on both sides of the second waveguide along the first direction, and the first waveguide, the second waveguide and the electrodes extend in the second direction, and the first direction is perpendicular to the second direction. The width of the main electrode in the first direction is gradual. By changing the width of the main electrode in the first direction, the radio frequency characteristic parameters of the modulation zone can also be changed, thereby improving the flexibility of the present solution. In addition, the width transition of the main electrode is smoother, which can more effectively avoid reflections during the transmission of electrical signals, and is conducive to improving the modulation performance.

[0037] In a fourth aspect, embodiments of the present application provide an optical chip comprising a coupler, a waveguide, and an electro-optical modulator as described in any one of the embodiments of aspects 1 to 3. The coupler is configured to couple light from a laser to the waveguide, and the electro-optical modulator is configured to modulate the light from the waveguide to generate an optical signal.

[0038] In a fifth aspect, embodiments of the present application provide an optical module. The optical module includes: at least one laser, a driver, and at least one electro-optical modulator as described in any of the embodiments of aspects 1 to 3. The at least one laser is configured to emit light. The driver is configured to drive the at least one electro-optical modulator to modulate the light from the laser to generate an optical signal.

[0039] In some possible implementations, the optical module includes multiple lasers and multiple electro-optical modulators, and further includes a wavelength division multiplexer (WDM) configured to combine optical signals output by the multiple electro-optical modulators and output the combined optical signal.

[0040] In a sixth aspect, an embodiment of the present application provides an optical communication system, which includes a first communication device and a second communication device, wherein the first communication device and the second communication device both include the optical module described in the fourth aspect, and are used to transmit optical signals between the first communication device and the second communication device.

[0041] In an embodiment of the present application, electrodes are distributed on both sides of the waveguide of the electro-optic modulator, wherein the electrodes include a main electrode extending in the same direction as the waveguide and an auxiliary electrode extending from the main electrode toward the waveguide. In the direction of the waveguide extension, the electro-optic modulator is divided into multiple modulation zones. In at least one direction parallel and perpendicular to the waveguide extension direction, the structural characteristics of the auxiliary electrodes in different modulation zones are different, resulting in different RF characteristic parameters in different modulation zones. This facilitates the flexible configuration of the RF characteristic parameters of each modulation zone according to actual conditions to meet RF matching requirements, reduce reflections during electrical signal transmission, and help increase bandwidth and reduce power consumption, thereby improving electro-optical modulation performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG1( a ) is a schematic diagram of an optical fiber communication system;

[0043] FIG1( b ) is a schematic structural diagram of an optical chip according to an embodiment of the present application;

[0044] FIG2 is a schematic diagram of a scenario in which an electrical chip drives an electro-optical modulator in an embodiment of the present application;

[0045] FIG3 is a schematic diagram of a first structure of an electro-optical modulator according to an embodiment of the present application;

[0046] FIG4 is a schematic diagram of a second structure of an electro-optical modulator according to an embodiment of the present application;

[0047] FIG5 is a schematic diagram of a third structure of an electro-optical modulator according to an embodiment of the present application;

[0048] FIG6 is a schematic diagram of a fourth structure of an electro-optical modulator according to an embodiment of the present application;

[0049] FIG7 is a schematic diagram of a first structure of an auxiliary electrode in an embodiment of the present application;

[0050] FIG8 is a schematic diagram of a second structure of an auxiliary electrode in an embodiment of the present application;

[0051] FIG9 is a schematic diagram of a fifth structure of an electro-optical modulator according to an embodiment of the present application;

[0052] FIG10 is a schematic diagram of a sixth structure of an electro-optical modulator according to an embodiment of the present application;

[0053] FIG11 is a schematic diagram of a third structure of an auxiliary electrode in an embodiment of the present application;

[0054] FIG12 is a schematic diagram of a fourth structure of an auxiliary electrode in an embodiment of the present application;

[0055] FIG13 is a schematic diagram of a seventh structure of an electro-optical modulator according to an embodiment of the present application;

[0056] FIG14 is a schematic diagram of an eighth structural embodiment of the electro-optical modulator according to the present application;

[0057] FIG15 is a ninth structural diagram of the electro-optic modulator in an embodiment of the present application. DETAILED DESCRIPTION

[0058] The embodiments of the present application provide an electro-optical modulator, an optical module, and an optical chip, which facilitate flexible configuration of the radio frequency characteristic parameters of each modulation zone within the electro-optical modulator according to actual conditions, so as to meet the requirements of radio frequency matching, reduce reflections during the transmission of electrical signals, and help improve bandwidth and reduce power consumption, thereby improving electro-optical modulation performance.

[0059] It should be noted that the terms "first", "second", etc. (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way are interchangeable where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0060] Figure 1(a) is a schematic diagram of a fiber-optic communication system. As shown in Figure 1(a), the transmitter includes an electronic chip, a laser, a modulator, and a wavelength division multiplexer. The transmitter is used to convert electrical signals into optical signals. The laser is used to emit laser light. The electronic chip is used to output an electrical signal to the modulator, driving the modulator to modulate the laser light emitted by the laser to produce an optical signal. This electronic chip can also be referred to as a "driver." Optionally, in the case of multiple optical signals, a wavelength division multiplexer is used to combine optical signals of different wavelengths and couple the combined optical signal into an optical fiber for transmission. The receiver includes a wavelength division multiplexer, a detector, and an electronic chip. The receiver is used to convert optical signals into electrical signals. The wavelength division multiplexer is used to separate optical signals of different wavelengths and output them to different detectors, while the electronic chip drives the detectors to convert optical signals into electrical signals. It should be understood that the modulator is primarily used in the transmitter of a fiber-optic communication system. The modulator can specifically be an electro-optical modulator, such as a Mach-Zehnder modulator (MZM). External modulation is used to convert electrical signals into optical signals by adding them to an optical carrier wave to change the optical signal's characteristics, such as phase or intensity. It should also be understood that the transmitter mentioned above can be understood as the optical transmitting unit in an optical module, and the receiver mentioned above can be understood as the optical receiving unit in an optical module.

[0061] Figure 1(b) is a schematic diagram of the structure of an optical chip in an embodiment of the present application. As shown in Figure 1(b), the optical chip includes a coupler, a waveguide, and an electro-optical modulator. The coupler is used to couple light from a laser to the waveguide, which then transmits the light to the electro-optical modulator. The electro-optical modulator modulates the light from the waveguide according to the radio frequency signal from the electronic chip to generate an optical signal and outputs it.

[0062] Figure 2 is a schematic diagram of a scenario in which an electrical chip drives an electro-optic modulator in an embodiment of the present application. As shown in Figure 2, one end of the electrode in the electro-optic modulator is connected to a resistor Rs in the electrical chip, and the other end of the electrode in the electro-optic modulator is connected to a resistor Rt. The single-ended characteristic impedance of the electro-optic modulator is denoted as Z, and the differential characteristic impedance is denoted as 2*Z. It should be understood that in order to meet RF matching, Rs=Z=Rt is generally required. However, the Rs value of current mainstream electrical chips is generally 50Ohms, while the Z value of common silicon optical modulators is generally 30Ohms, which is a significant difference. In this case, if Rs=Z=Rt=50Ohms, although the RF matching and low power consumption characteristics can be met, it is difficult to achieve a high modulation bandwidth. If Rs=Z=Rt=30Ohms, although the RF matching and high bandwidth characteristics can be met, it is difficult to achieve low power consumption. If Rs=Z≠Rt, the bandwidth and power consumption performance can be improved, but the RF matching requirements are not met, which can cause reflection problems in the transmission of electrical signals in the electro-optic modulator, resulting in poor electro-optic modulation performance. That is, when the characteristic impedance Z of the electro-optic modulator is taken as a single fixed value, no matter how Rs and Rt are taken, it is difficult to achieve the simultaneous satisfaction of RF matching, high bandwidth and low power consumption characteristics.

[0063] To this end, the electro-optical modulator provided by the present application is divided into a plurality of modulation zones, and the structural features in different modulation zones may be different, so that the radio frequency characteristic parameters (including characteristic impedance and microwave refractive index, etc.) of different modulation zones are different. In this way, it is convenient to flexibly configure the radio frequency characteristic parameters of each modulation zone according to actual conditions to meet the requirements of radio frequency matching, reduce the reflection during the transmission of electrical signals, and help to improve bandwidth and reduce power consumption, thereby improving electro-optical modulation performance. For example, the radio frequency characteristic parameters of the modulation zone close to Rs are different from the radio frequency characteristic parameters of the modulation zone close to Rt. By reasonably designing Rs, Rt and the radio frequency characteristic parameters of each modulation zone, it is possible to ensure the high bandwidth and low power consumption characteristics of the electro-optical modulator, and also achieve radio frequency matching with the electrical chip.

[0064] Figure 3 is a schematic diagram of the first structure of the electro-optical modulator in an embodiment of the present application. As shown in Figure 3, the electro-optical modulator includes a beam splitting module, a beam combining module, a waveguide 1 and a waveguide 2. The two ends of waveguide 1 are respectively connected to the beam splitting module and the beam combining module, and the two ends of waveguide 2 are respectively connected to the beam splitting module and the beam combining module. The beam splitting module is used to split the input light and transmit the split light to waveguide 1 and waveguide 2 respectively. The beam combining module is used to combine the light transmitted by waveguide 1 and the light transmitted by waveguide 2. It should be understood that waveguide 1 and waveguide 2 can be made of other electro-optical materials similar to LN, such as lithium niobate (LN), silicon, silicon nitride or barium titanate (BaTiO3), and the specific details are not limited here.

[0065] It should be noted that electro-optic modulators can generally be divided into silicon optical modulators and electro-optic material modulators based on the waveguide material used. Electro-optic material modulators include thin film lithium niobate (TFLN) modulators, barium titanate (BaTiO3, BTO) modulators, and piezoelectric devices made of lead zirconate titanate (PZT) modulators. The main structural difference between silicon optical modulators and electro-optic material modulators is that silicon optical modulators include a doping structure, while electro-optic material modulators do not. The following describes the different structures of silicon optical modulators and electro-optic material modulators.

[0066] Figure 4 is a schematic diagram of the second structure of the electro-optical modulator in an embodiment of the present application. As shown in Figure 4, this is a top view of a silicon optical modulator. Waveguide 1 and waveguide 2 extend along the X direction, which is also the direction of light transmission. Multiple electrodes are distributed on both sides of waveguide 1 and waveguide 2 along the Y direction, wherein the X direction and the Y direction are perpendicular to each other. As an example, a GSSG type electrode structure is adopted, wherein electrode 1 and electrode 2 are distributed on both sides of waveguide 1, and electrode 3 and electrode 4 are distributed on both sides of waveguide 2. Electrode 1 and electrode 4 are grounded, and electrode 2 and electrode 3 are loaded with differential electrical signals S+ and S-, respectively. In some other possible scenarios, a grounded electrode can also be added between electrode 2 and electrode 3, that is, a GSGSG type electrode structure is adopted.

[0067] FIG5 is a schematic diagram of the third structure of the electro-optic modulator in an embodiment of the present application. As shown in FIG5 , this is a side cross-sectional view of a silicon optical modulator, in which the Z direction is perpendicular to the X direction and the Y direction, respectively. Taking waveguide 1 and electrodes 1 and 2 on both sides as an example, waveguide 1 includes a P-type doped region and an N-type doped region. Electrode 1 is connected to the N-type doped region in waveguide 1 via an N-type doped structure. The N-type doped structure can conduct the electrical signal loaded on electrode 1 to the N-type doped region in waveguide 1. Electrode 2 is connected to the P-type doped region in waveguide 1 via a P-type doped structure. The P-type doped structure can conduct the electrical signal loaded on electrode 2 to the P-type doped region in waveguide 1. The electrical signal loaded on electrode 1 is conducted to the N-type doped region of waveguide 1 via the N-type doped structure, and the electrical signal loaded on electrode 2 is conducted to the P-type doped region of waveguide 1 via the P-type doped structure. In some other possible scenarios, electrode 1 can also be connected to the P-type doped region in waveguide 1 via a P-type doped structure, and electrode 2 can be connected to the N-type doped region in waveguide 1 via an N-type doped structure. It should be understood that the present application does not limit the doping concentrations of the P-type doping structure and the N-type doping structure in the Y direction. The doping concentration of the P-type doping structure in the Y direction can be the same or variable. Similarly, the doping concentration of the N-type doping structure in the Y direction can be the same or variable.

[0068] FIG6 is a schematic diagram of the fourth structure of the electro-optic modulator in an embodiment of the present application. As shown in FIG6 , this is a top view of an electro-optic material modulator. The difference from the silicon optical modulator shown in FIG4 and FIG5 is that the electro-optic material modulator does not have a P-type doping structure and an N-type doping structure, and there is no P-type doping region and an N-type doping region in the waveguide. As an example, a GSG-type electrode structure is adopted, with electrodes 1 and 2 distributed on both sides of waveguide 1, and electrodes 2 and 3 distributed on both sides of waveguide 2. Electrode 1 and electrode 3 are grounded, and electrode 2 is used to load a differential S+ electrical signal or a differential S- electrical signal. In addition, the electrodes in the silicon optical modulators shown in FIG4 and FIG5 are mainly used for conducting electricity, while the electrodes in the electro-optic material modulator shown in FIG6 are used to form an electric field. For example, in Figure 6, an electric field is formed between electrode 1 and electrode 2, and an electric field is formed between electrode 2 and electrode 3. When an electric field is applied to waveguide 1 from the outside, the refractive index of the material of waveguide 1 may change due to the linear electro-optic effect of the electro-optic material. This change can change the propagation characteristics of light in the waveguide, such as the phase, amplitude or polarization of the light, thereby modulating the light transmitted in the waveguide.

[0069] It should be understood that the present application does not limit the electrode design method adopted by the electro-optical modulator. In addition to the above-mentioned GSG-type electrode structure, GSSG-type electrode structure and GSGSG-type electrode structure, in some possible implementations, only two electrodes can be designed, and waveguide 1 and waveguide 2 are both located between these two electrodes. No drawings are provided here for display.

[0070] It should be noted that the electro-optic modulator divides the modulation zones into different regions based on the different structural features of the electrodes within them. That is, the electrodes within two adjacent modulation zones have different structural features, and the modulation zones are distributed along the extension direction of waveguide 1 and waveguide 2. The following describes these electrode structural features in detail.

[0071] Specifically, each electrode consists of a main electrode and an auxiliary electrode connected to the main electrode. The main electrode extends in the same direction as the waveguide, while the auxiliary electrode extends toward the waveguide. The auxiliary electrodes are designed to optimize modulation performance. For example, Figure 4 shows a T-shaped auxiliary electrode structure: the auxiliary electrodes on electrodes 1 and 2 on either side of waveguide 1 extend toward waveguide 1, while the auxiliary electrodes on electrodes 3 and 4 on either side of waveguide 2 extend toward waveguide 2.

[0072] FIG7 is a schematic diagram of the first structure of the auxiliary electrode in an embodiment of the present application. It should be understood that the auxiliary electrode provided in this application is not limited to the T-shaped structure shown in FIG5. For ease of description, the portion of the auxiliary electrode extending in the Y direction is referred to as electrode structure 1, and the portion of the auxiliary electrode extending in the X direction is referred to as electrode structure 2. Any auxiliary electrode structure having electrode structure 1 and electrode structure 2 is within the scope of protection of this application. Among them, one end of electrode structure 1 is connected to the corresponding main electrode, and the other end of electrode structure 1 is connected to electrode structure 2.

[0073] It should be noted that the present application specifically divides different modulation zones based on the different structural features of the auxiliary electrodes, and the present application does not limit the number of auxiliary electrodes in each modulation zone. For example, the number of auxiliary electrodes in each modulation zone can be the same; for another example, the number of auxiliary electrodes in different modulation zones can also be different. In other words, each auxiliary electrode in the same modulation zone has the same structural features, while the structural features of the auxiliary electrodes in two adjacent modulation zones are different. It should be understood that the present application does not limit the number of modulation zones and the length of each modulation zone in the X direction. For example, there are 5 modulation zones, and the length of each modulation zone in the X direction is 400um.

[0074] It should also be noted that any parameter that can reflect the auxiliary electrode structure can be regarded as a structural feature of the auxiliary electrode, and the structural features of the auxiliary electrode include but are not limited to the shape and size of the auxiliary electrode. As an example, the shapes of the auxiliary electrodes in adjacent modulation areas are different. For example, the change in the distance gh between the two electrode structures 1 in Figure 8 can be regarded as a different shape of the auxiliary electrodes; for another example, the change in the number of electrode structures 1 in Figure 10 can also be regarded as a different shape of the auxiliary electrodes. As another example, the shapes of the auxiliary electrodes in adjacent modulation areas are the same, but the specific sizes are different. For example, any change in the parameters marked in Figures 7 and 11 can be regarded as a different size. As another example, the shapes and sizes of the auxiliary electrodes in adjacent modulation areas are different. In other words, the cross-section of the auxiliary electrode displayed in the plane formed by the above-mentioned X-direction and Y-direction can be called the cross-section of the auxiliary electrode. The different structural features of the auxiliary electrodes in adjacent modulation areas can also be reflected in the different cross-sections of the auxiliary electrodes in adjacent modulation areas, including but not limited to different shapes of the cross-sections and different sizes of the cross-sections.

[0075] The following will provide a detailed description in conjunction with different embodiments.

[0076] Taking the adjacent modulation area 1 and modulation area 2 as an example, the structural characteristics of the auxiliary electrodes in these two modulation areas are different and meet at least one of the following conditions: 1. The structural characteristics of the auxiliary electrode in the modulation area 1 in the X direction are different from the structural characteristics of the auxiliary electrode in the modulation area 2 in the X direction; 2. The structural characteristics of the auxiliary electrode in the modulation area 1 in the Y direction are different from the structural characteristics of the auxiliary electrode in the modulation area 2 in the Y direction. It should be understood that within the plane formed by the above-mentioned X direction and Y direction, the structure of the auxiliary electrode is split into an electrode structure 1 extending along the Y direction and an electrode structure 2 extending along the X direction. In other words, 1. The structural parameters of the electrode structure 1 in adjacent modulation areas are different; 2. The structural parameters of the electrode structure 2 in adjacent modulation areas are different. The following introduces them respectively in combination with some specific design methods.

[0077] In one possible embodiment, the structural dimensions of the electrode structure 1 of the auxiliary electrode in the modulation area 1 are different from the structural dimensions of the electrode structure 1 of the auxiliary electrode in the modulation area 2, and / or the structural dimensions of the electrode structure 2 of the auxiliary electrode in the modulation area 1 are different from the structural dimensions of the electrode structure 2 of the auxiliary electrode in the modulation area 2. Specifically, taking FIG. 7 as an example, the length of the electrode structure 1 of the auxiliary electrode in the Y direction is denoted as Wh, the width of the electrode structure 1 of the auxiliary electrode in the X direction is denoted as Lh, the length of the electrode structure 2 of the auxiliary electrode in the X direction is denoted as Ls, and the width of the electrode structure 2 of the auxiliary electrode in the Y direction is denoted as Ws.

[0078] As a first example, the length Wh-1 of the electrode structure 1 of the auxiliary electrode in modulation zone 1 is different from the length Wh-2 of the electrode structure 1 of the auxiliary electrode in modulation zone 2. In one possible scenario, as shown in FIG4 , along the X direction from modulation zone 1 to modulation zone n, the length Wh of the electrode structure 1 of the auxiliary electrode gradually increases, that is, Wh-1 < Wh-2 < … < Wh-n, and the characteristic impedance of each modulation zone gradually decreases, so that the characteristic impedance of modulation zone 1 is close to the resistor Rs, and the characteristic impedance of modulation zone n is close to the resistor Rt, which is conducive to achieving RF matching.

[0079] As a second example, the width Lh-1 of the electrode structure 1 of the auxiliary electrode in modulation zone 1 is different from the width Lh-2 of the electrode structure 1 of the auxiliary electrode in modulation zone 2. In one possible scenario, as shown in FIG6 , along the X direction from modulation zone 1 to modulation zone n, the width Lh of the electrode structure 1 of the auxiliary electrode gradually increases, that is, Lh-1<Lh-2<…<Lh-n, and the characteristic impedance of each modulation zone gradually decreases, so that the characteristic impedance of modulation zone 1 is close to the resistor Rs, and the characteristic impedance of modulation zone n is close to the resistor Rt, which is conducive to achieving RF matching.

[0080] As a third example, the length Ls-1 of the electrode structure 2 of the auxiliary electrode in modulation zone 1 is different from the length Ls-2 of the electrode structure 2 of the auxiliary electrode in modulation zone 2. In one possible scenario, along the X direction, the length Ls of the electrode structure 2 of the auxiliary electrode gradually increases from modulation zone 1 to modulation zone n, that is, Ls-1 < Ls-2 < ... < Ls-n, which is conducive to improving modulation efficiency.

[0081] As a fourth example, the width Ws-1 of the electrode structure 2 of the auxiliary electrode in modulation zone 1 is different from the width Ws-2 of the electrode structure 2 of the auxiliary electrode in modulation zone 2. In one possible scenario, along the X direction, from modulation zone 1 to modulation zone n, the width Ws of the electrode structure 2 of the auxiliary electrode gradually decreases, that is, Ws-1>Ws-2>…>Ws-n, which helps to achieve a smoother transition.

[0082] As a fifth example, in a scenario where each modulation region includes multiple auxiliary electrodes, the spacing between two adjacent auxiliary electrodes in the modulation region is different from the spacing between two adjacent auxiliary electrodes in the modulation region 2. For example, as shown in FIG7 , the spacing may be the spacing p between two adjacent electrode structures 2. Alternatively, the spacing may be the spacing between two adjacent electrode structures 1.

[0083] It should be understood that the above five examples can be combined in any manner and are not listed here one by one. It should also be understood that the above five examples do not limit the gradual change trend of the structural characteristic parameters of the auxiliary electrode, and gradually increasing, gradually decreasing, or alternating increasing and decreasing are all possible.

[0084] It should be noted that in the electro-optic modulator shown in Figure 6 above, the T-shaped auxiliary electrode is used to form the electric field. The length Wh of the auxiliary electrode structure 1 in the Y direction and the length Ls of the auxiliary electrode structure 2 in the X direction have a significant impact on the electric field intensity, and thus the modulation effect. Typically, in electro-optic modulators, the two parameters Wh and Ls are set to fixed values. Apart from these, other structural characteristic parameters of the auxiliary electrode vary within different modulation regions.

[0085] Figure 8 is a schematic diagram of a second auxiliary electrode structure in an embodiment of the present application. Unlike the auxiliary electrodes shown in Figure 7 , each auxiliary electrode in Figure 8 includes multiple electrode structures 1 extending along the Y direction. The distance between two adjacent electrode structures 1 on the same auxiliary electrode is denoted as gh. The distance gh-1 between two adjacent electrode structures 1 of the auxiliary electrode in modulation zone 1 is different from the distance gh-2 between two adjacent electrode structures 1 of the auxiliary electrode in modulation zone 2.

[0086] FIG9 is a schematic diagram of the fifth structure of the electro-optic modulator in an embodiment of the present application. As shown in FIG9 , in one possible scenario, along the X direction from modulation zone 1 to modulation zone n, the distance gh between two adjacent electrode structures 1 of the auxiliary electrode gradually increases, that is, gh-1 < gh-2 < … < gh-n, and the characteristic impedance of each modulation zone gradually decreases, so that the characteristic impedance of modulation zone 1 is close to the resistor Rs, and the characteristic impedance of modulation zone n is close to the resistor Rt, which is conducive to achieving RF matching.

[0087] FIG10 is a schematic diagram of the sixth structure of the electro-optic modulator in an embodiment of the present application. As shown in FIG10 , in one possible scenario, the number of electrode structures 1 of the auxiliary electrode in modulation zone 1 is different from the number of electrode structures 1 of the auxiliary electrode in modulation zone 2. For example, along the X direction from modulation zone 1 to modulation zone n, the number of electrode structures 1 of the auxiliary electrode gradually increases, and the characteristic impedance of each modulation zone gradually decreases, so that the characteristic impedance of modulation zone 1 is close to the resistor Rs, and the characteristic impedance of modulation zone n is close to the resistor Rt, which is conducive to achieving RF matching.

[0088] Figure 11 is a schematic diagram of a third structure of an auxiliary electrode in an embodiment of the present application. Unlike the auxiliary electrode shown in Figure 7, as shown in Figure 11, the auxiliary electrode further includes an electrode structure 3 extending in the X direction. Electrode structure 3 is connected to electrode structure 1 and is located between electrode structure 2 and the main electrode. The length of electrode structure 3 of the auxiliary electrode in the X direction is denoted as Lstu, the width of electrode structure 3 in the Y direction is denoted as Wstu, and the distance between electrode structure 2 and electrode structure 3 is denoted as Whtu.

[0089] As an example, the length Lstu-1 of the electrode structure 3 of the auxiliary electrode in modulation area 1 is different from the length Lstu-2 of the electrode structure 2 of the auxiliary electrode in modulation area 2. In one possible scenario, along the X direction from modulation area 1 to modulation area n, the length Lstu of the electrode structure 3 of the auxiliary electrode gradually increases, that is, Lstu-1 < Lstu-2 < ... < Lstu-n, which is conducive to improving modulation efficiency.

[0090] As another example, the width Wstu-1 of the electrode structure 3 of the auxiliary electrode in modulation zone 1 is different from the width Wstu-2 of the electrode structure 2 of the auxiliary electrode in modulation zone 2. In one possible scenario, along the X direction, from modulation zone 1 to modulation zone n, the width Wstu of the electrode structure 3 of the auxiliary electrode gradually increases, that is, Wstu-1>Wstu-2>…>Wstu-n, which helps to achieve a smoother transition.

[0091] As another example, the distance Whtu-1 between the electrode structure 2 and the electrode structure 3 of the auxiliary electrode in modulation area 1 is different from the distance Whtu-2 between the electrode structure 2 and the electrode structure 3 of the auxiliary electrode in modulation area 2. In one possible scenario, along the X direction from modulation area 1 to modulation area n, the distance Whtu between the electrode structure 2 and the electrode structure 3 of the auxiliary electrode gradually decreases, that is, Whtu-1>Whtu-2>…>Whtu-n, which is conducive to improving modulation efficiency.

[0092] It should be understood that the above three examples can be combined in any manner and are not listed here one by one. It should also be understood that the above three examples do not limit the gradual change trend of the structural characteristic parameters of the auxiliary electrode, and gradually increasing, gradually decreasing, or alternating increasing and decreasing are all possible.

[0093] In some possible implementations, the width of the main electrode in the Y direction is gradually varied. By varying the width of the main electrode in the first direction, the RF characteristic parameters of the modulation zone can also be varied, thereby increasing the flexibility of the present solution. Furthermore, a smoother width transition of the main electrode can more effectively avoid reflections during electrical signal transmission, thereby improving modulation performance. For example, the width of the main electrode can gradually widen along the X direction. Specifically, the width of the main electrode can gradually vary in both directions; alternatively, one side of the main electrode can remain unchanged while the other side gradually varies, resulting in a gradual width variation.

[0094] In some possible implementations, for the changes in the structural characteristics of the auxiliary electrodes in different modulation zones described in any of the above embodiments, the amplitude of the change in the structural characteristics of the auxiliary electrodes in each of two consecutive modulation zones along the X direction from modulation zone 1 to modulation zone n remains consistent, which is beneficial for reducing reflections formed during the transmission of electrical signals, ensuring that the transmission speed of electrical signals remains unchanged, and improving modulation performance. Taking the length Wh-1 of the electrode structure 1 of the above-mentioned auxiliary electrode as an example, Wh-2-Wh-1=Wh-3-Wh-2=…=Wh-n-Wh-n-1. In addition, the other characteristic parameters of the auxiliary electrodes mentioned above are also similar and will not be repeated here one by one.

[0095] FIG12 is a schematic diagram of a fourth auxiliary electrode structure in an embodiment of the present application. It should be understood that in addition to the auxiliary electrode structures described in the above embodiments, the auxiliary electrode may also adopt other structural designs, as long as the auxiliary electrode has an electrode structure 1 extending along the Y direction and an electrode structure 2 extending along the X direction. For example, as shown in FIG12 , the auxiliary electrode may also adopt an L-shaped structure or a Z-shaped structure.

[0096] It should be noted that for the silicon optical modulators shown in Figures 4 and 5 above, in addition to the structural characteristics of the electrodes affecting the RF characteristic parameters of the modulation area, the characteristics of the P-type doped area and the N-type doped area will also affect the RF characteristic parameters, modulation efficiency, and modulation bandwidth. To this end, the characteristics of the P-type doped area and the N-type doped area in different modulation areas can also be different, so that the capacitance and resistance values ​​of different modulation areas are different, which in turn affects the RF characteristic parameters. It is convenient to flexibly configure the RF characteristic parameters of each modulation area according to actual conditions, which is conducive to improving the overall bandwidth and reducing reflections during the transmission of electrical signals, thereby improving the electro-optical modulation performance. The following is a detailed introduction based on the characteristics of the P-type doped area and the N-type doped area.

[0097] FIG13 is a schematic diagram of the seventh structure of an electro-optical modulator in an embodiment of the present application. As shown in FIG13 , taking the P-type and N-type doped regions on both sides of waveguide 1 or waveguide 2 as an example, the distance between the P-type and N-type doped regions in modulation zone 1 is different from the distance between the P-type and N-type doped regions in modulation zone 2. In one possible scenario, the distance between the P-type and N-type doped regions can be gradual, that is, the distance between the P-type and N-type doped regions in the same modulation zone also varies gradually. In another possible scenario, the distance between the P-type and N-type doped regions can also vary in a step-like manner, that is, the distance between the P-type and N-type doped regions in each modulation zone is the same, and the distance between the P-type and N-type doped regions in different modulation zones varies. As an example, along the X direction, from modulation zone 1 to modulation zone n, the distance between the P-type and N-type doped regions gradually increases, which can gradually reduce the capacitance of the PN junction and reduce the loss of the electrical signal caused by increasing transmission distance, thereby increasing the bandwidth while maintaining high modulation efficiency. It should be understood that the distance between the P-type doped region and the N-type doped region can be gradually increased in a linear or nonlinear manner. If it is a linear change, it helps to reduce reflections caused by the electrical signal during transmission, ensure that the electrical signal transmission speed remains unchanged, and improve modulation performance.

[0098] FIG14 is a schematic diagram of the eighth structure of an electro-optic modulator according to an embodiment of the present application. As shown in FIG14 , the cross-section of a P-type doped region shown in the plane defined by the X and Y directions can be referred to as the cross-section of the P-type doped region, and the cross-section of an N-type doped region can be referred to as the cross-section of the N-type doped region. Taking the P-type and N-type doped regions on either side of waveguide 1 or waveguide 2 as an example, the relative cross-sectional size ratio of the P-type and N-type doped regions within modulation region 1 is different from the relative cross-sectional size ratio of the P-type and N-type doped regions within modulation region 2. In one possible scenario, the relative cross-sectional size ratio of the P-type and N-type doped regions can vary gradually, i.e., the relative cross-sectional size ratio of the P-type and N-type doped regions within the same modulation region also varies gradually. In another possible scenario, the relative cross-sectional size ratio of the P-type and N-type doped regions can vary in a step-like manner, i.e., the relative cross-sectional size ratio of the P-type and N-type doped regions within each modulation region is the same, while the relative cross-sectional size ratio of the P-type and N-type doped regions within different modulation regions varies. As an example, along the X-direction from modulation zone 1 to modulation zone n, the proportion of P-type doped regions in each modulation zone gradually increases, which is beneficial to improving modulation efficiency. As another example, along the X-direction from modulation zone 1 to modulation zone n, the proportion of N-type doped regions in each modulation zone gradually increases, which is beneficial to improving modulation bandwidth.

[0099] FIG15 is a ninth structural diagram of the electro-optical modulator in an embodiment of the present application. As shown in FIG15 , taking the P-type doping region and the N-type doping region on both sides of the waveguide 1 or the waveguide 2 as an example, the doping concentration of the P-type doping region in the modulation region 1 is different from the doping concentration of the P-type doping region in the modulation region 2, and / or the doping concentration of the N-type doping region in the modulation region 1 is different from the doping concentration of the N-type doping region in the modulation region 2. In one possible scenario, the doping concentrations of the P-type doping region and the N-type doping region can be gradual, that is, the doping concentrations of the P-type doping region and the N-type doping region in the same modulation region are also gradual. In another possible scenario, the doping concentrations of the P-type doping region and the N-type doping region can also be step-type, that is, the doping concentrations of the P-type doping region in each modulation region are the same, the doping concentrations of the N-type doping region in each modulation region are the same, the doping concentrations of the P-type doping regions in different modulation regions are changing, and the doping concentrations of the N-type doping regions in different modulation regions are changing. As an example, along the X direction from modulation zone 1 to modulation zone n, the doping concentration of the P-type doping region gradually decreases, and the doping concentration of the N-type doping region gradually decreases, which is conducive to improving the modulation bandwidth.

[0100] It should be understood that the above-mentioned embodiments with different structural features of the auxiliary electrode can be arbitrarily combined, and the present application does not limit the trend of the structural feature parameters of the auxiliary electrode changing with the arrangement of the modulation zone. It is possible for them to gradually increase, gradually decrease, or alternately increase and decrease. The above-mentioned embodiments with different structural features of the P-type doping region and the N-type doping region can also be arbitrarily combined. The present application does not limit the trend of the structural feature parameters of the P-type doping region and the N-type doping region changing with the arrangement of the modulation zone. It is possible for them to gradually increase, gradually decrease, or alternately increase and decrease. Similarly, the embodiments with different structural features of the auxiliary electrode and the embodiments with different structural features of the P-type doping region and the N-type doping region can also be arbitrarily combined, and they will not be described one by one here.

[0101] It should be noted that the above embodiments are intended only to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they may still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents; and such modifications or replacements do not deviate from the spirit and scope of the technical solutions of the various embodiments of the present application.

Claims

1. An electro-optic modulator, characterized in that: include: A first waveguide, a second waveguide and a plurality of electrodes, wherein the first waveguide and the second waveguide are used to transmit light, the plurality of electrodes are distributed on both sides of the first waveguide and the second waveguide along a first direction, each of the electrodes comprises a main electrode and a plurality of auxiliary electrodes connected to the main electrode, the first waveguide, the second waveguide and the main electrode extend toward a second direction, the plurality of auxiliary electrodes are distributed along the second direction, the first direction is perpendicular to the second direction, the electro-optic modulator comprises a plurality of modulation areas in the second direction, the first modulation area and the second modulation area are two adjacent modulation areas, and the structural features of the auxiliary electrodes in the first modulation area are different from the structural features of the auxiliary electrodes in the second modulation area.

2. The electro-optic modulator according to claim 1, characterized in that In a plane including the first direction and the second direction, a cross section of any auxiliary electrode in the first modulation area is different from a cross section of any auxiliary electrode in the second modulation area.

3. The electro-optic modulator according to claim 1 or 2, characterized in that: Each of the auxiliary electrodes includes a first electrode structure extending in the first direction and a second electrode structure extending in the second direction, one end of the first electrode structure is connected to the corresponding main electrode, and the other end of the first electrode structure is connected to the second electrode structure.

4. The electro-optic modulator according to claim 3, characterized in that The length of the first electrode structure of any auxiliary electrode in the first modulation area in the first direction is different from the length of the first electrode structure of any auxiliary electrode in the second modulation area in the first direction, and / or the length of the second electrode structure of any auxiliary electrode in the first modulation area in the second direction is different from the length of the second electrode structure of any auxiliary electrode in the second modulation area in the second direction.

5. The electro-optic modulator according to claim 4, characterized in that The length of the first electrode structure of each auxiliary electrode in the same modulation area in the first direction is the same, and the length of the second electrode structure of each auxiliary electrode in the same modulation area in the second direction is the same; The length of the first electrode structure of the auxiliary electrodes of the multiple modulation areas in the light transmission direction gradually increases in the first direction, and / or the length of the second electrode structure of the auxiliary electrodes of the multiple modulation areas in the light transmission direction gradually increases in the second direction.

6. The electro-optic modulator according to claim 5, characterized in that The length variation range of the first electrode structure of the auxiliary electrodes in each two adjacent modulation areas in the first direction is the same, and / or the length variation range of the second electrode structure of the auxiliary electrodes in each two adjacent modulation areas in the second direction is the same.

7. The electro-optic modulator according to any one of claims 3 to 6, characterized in that: Each of the auxiliary electrodes includes two of the first electrode structures, and the distance between the two first electrode structures of any auxiliary electrode in the first modulation area is different from the distance between the two first electrode structures of any auxiliary electrode in the second modulation area.

8. The electro-optic modulator according to claim 7, characterized in that: The distance between the two first electrode structures of each auxiliary electrode in the same modulation area is the same, and the distance between the two first electrode structures of the auxiliary electrodes of the multiple modulation areas in the light transmission direction gradually increases.

9. The electro-optic modulator according to claim 8, characterized in that: The distance between the two first electrode structures of the auxiliary electrodes in every two adjacent modulation areas has the same variation range.

10. The electro-optic modulator according to any one of claims 3 to 9, characterized in that: The width of the first electrode structure of any auxiliary electrode in the first modulation area in the second direction is different from the width of the first electrode structure of any auxiliary electrode in the second modulation area in the second direction, and / or the width of the second electrode structure of any auxiliary electrode in the first modulation area in the first direction is different from the width of the second electrode structure of any auxiliary electrode in the second modulation area in the first direction.

11. The electro-optic modulator according to any one of claims 3 to 10, characterized in that: The number of first electrode structures of any auxiliary electrode in the first modulation area is different from the number of first electrode structures of any auxiliary electrode in the second modulation area.

12. The electro-optic modulator according to any one of claims 3 to 11, characterized in that: Each of the auxiliary electrodes further comprises a third electrode structure extending in the second direction, the third electrode structure is connected to the first electrode structure, and the third electrode structure is located between the second electrode structure and the corresponding main electrode; The length of the third electrode structure of any auxiliary electrode in the first modulation area in the second direction is different from the length of the third electrode structure of any auxiliary electrode in the second modulation area in the second direction, and / or the width of the third electrode structure of any auxiliary electrode in the first modulation area in the first direction is different from the width of the third electrode structure of any auxiliary electrode in the second modulation area in the first direction, and / or the distance between the second electrode structure and the third electrode structure of any auxiliary electrode in the first modulation area is different from the distance between the second electrode structure and the third electrode structure of any auxiliary electrode in the second modulation area.

13. The electro-optic modulator according to any one of claims 1 to 12, characterized in that: The distance between any two adjacent auxiliary electrodes in the first modulation area is different from the distance between any two adjacent auxiliary electrodes in the second modulation area.

14. The electro-optic modulator according to any one of claims 1 to 13, characterized in that: The width of the main electrode in the first direction is gradually changed.

15. The electro-optic modulator according to any one of claims 1 to 14, characterized in that: The electro-optic modulator further comprises a first P-type doping structure, a first N-type doping structure, a second P-type doping structure and a second N-type doping structure, the first waveguide comprises a first P-type doping region and a first N-type doping region, and the second waveguide comprises a second P-type doping region and a second N-type doping region; The electrode located on one side of the first waveguide is connected to the first P-type doped region through the first P-type doping structure, the electrode located on the other side of the first waveguide is connected to the first N-type doped region through the first N-type doping structure, the electrode located on one side of the second waveguide is connected to the second P-type doped region through the second P-type doping structure, and the electrode located on the other side of the second waveguide is connected to the second N-type doped region through the second N-type doping structure.

16. The electro-optic modulator according to claim 15, characterized in that The distance between the first P-type doped region and the first N-type doped region in the first modulation zone is different from the distance between the first P-type doped region and the first N-type doped region in the second modulation zone, and the distance between the second P-type doped region and the second N-type doped region in the first modulation zone is different from the distance between the second P-type doped region and the second N-type doped region in the second modulation zone.

17. The electro-optic modulator according to claim 15 or 16, characterized in that: In the plane where the first direction and the second direction are located, the relative size ratio of the cross-sections of the first P-type doped region and the first N-type doped region in the first modulation zone is different from the relative size ratio of the cross-sections of the first P-type doped region and the first N-type doped region in the second modulation zone, and the relative size ratio of the cross-sections of the second P-type doped region and the second N-type doped region in the first modulation zone is different from the relative size ratio of the cross-sections of the second P-type doped region and the second N-type doped region in the second modulation zone.

18. The electro-optic modulator according to any one of claims 15 to 17, characterized in that: The doping concentration of the first P-type doping region in the first modulation area is different from the doping concentration of the first P-type doping region in the second modulation area, and / or the doping concentration of the first N-type doping region in the first modulation area is different from the doping concentration of the first N-type doping region in the second modulation area; The doping concentration of the second P-type doping region in the first modulation zone is different from the doping concentration of the second P-type doping region in the second modulation zone, and / or the doping concentration of the second N-type doping region in the first modulation zone is different from the doping concentration of the second N-type doping region in the second modulation zone.

19. An optical module, characterized in that: include: at least one laser, a driver and at least one electro-optic modulator as claimed in any one of claims 1 to 18; The at least one laser is configured to emit light; The driver is used to drive the at least one electro-optical modulator to modulate the light from the laser to obtain an optical signal.

20. The optical module according to claim 19, characterized in that: The optical module includes a plurality of the lasers and a plurality of the electro-optical modulators, and the optical module also includes a wavelength division multiplexer; The wavelength division multiplexer is used to combine the optical signals output by the plurality of electro-optical modulators and output the combined optical signal.

21. An optical chip, characterized in that: include: A coupler, a waveguide, and an electro-optic modulator as claimed in any one of claims 1 to 18, wherein the coupler is used to couple light from a laser to the waveguide, and the electro-optic modulator is used to modulate the light from the waveguide to obtain an optical signal.

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