Electro-optical modulator, optical module and optical chip

Abstract

The embodiment of the invention discloses an electro-optical modulator, an optical module and an optical chip. Electrodes are distributed on the two sides of a waveguide of the electro-optical modulator, and the electrodes comprise a main electrode which is the same as the extending direction of the waveguide and an auxiliary electrode which extends out of the main electrode and faces the waveguide. In the extension direction of the waveguide, the electro-optical modulator is divided into a plurality of modulation areas, and the structural features of the auxiliary electrodes in the adjacent modulation areas are different, so that the radio frequency characteristic parameters of different modulation areas are different. In this way, the radio frequency characteristic parameters of the modulation areas can be flexibly configured according to the actual situation so as to meet the radio frequency matching requirement, the bandwidth can be improved, power consumption can be reduced, the reflection situation in the electric signal transmission process can be reduced, and therefore the electro-optical modulation performance can be improved.

Description

Technical Field

[0001] This 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

[0002] In an optical communication system, an optical module is an important component, mainly for completing the mutual conversion between electricity and light. With the development of optical modules towards higher speed, lower cost, and higher integration, on - chip integration technologies represented by silicon - based optical devices have been proposed and gradually developed and matured. Among them, an electro - optical modulator is one of the key devices, which is used to complete the conversion from an electrical signal to an optical signal.

[0003] With the continuous increase in the demand for communication capacity, the transmission rate of the communication system has also been increasing. Therefore, the co - design between an electrical integrated circuit (EIC) and an optical integrated circuit (PIC) has attracted increasing attention and become an important means to improve the transmission performance of the system. Currently, in an architecture including an on - EIC power driver and an on - PIC electro - optical modulator, it is difficult to simultaneously achieve characteristics such as radio - frequency parameter matching, high output swing, high bandwidth, and low power consumption, which restricts the improvement of electro - optical modulation performance. Summary of the Invention

[0004] Embodiments of this application provide an electro - optical modulator, an optical module, and an optical chip, which facilitate flexibly configuring the radio - frequency characteristic parameters of each modulation region in the electro - optical modulator according to actual situations to meet the requirements of radio - frequency matching, are beneficial to improving the bandwidth and reducing power consumption, and reducing the occurrence of reflections during the transmission of electrical signals, thereby improving the electro - optical modulation performance.

[0005] In a first aspect, embodiments of this application provide 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 for transmitting light, and the plurality of electrodes are used for transmitting 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 both sides of the second waveguide along a first direction. 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, the plurality of auxiliary electrodes are distributed along the second direction, and the first direction is perpendicular to the second direction. The auxiliary electrodes connected to the main electrodes on both sides of the first waveguide extend towards the first waveguide, and the auxiliary electrodes connected to the main electrodes on both sides of the second waveguide extend towards the second waveguide. The electro - optical modulator includes a plurality of modulation regions in the second direction, and the first modulation region and the second modulation region are two adjacent modulation regions. The structural characteristics of the auxiliary electrodes in the first modulation region are different from those of the auxiliary electrodes in the second modulation region.

[0006] In this embodiment, the structural features of the auxiliary electrodes in different modulation regions are different, so that the radio frequency characteristic parameters of different modulation regions are different. In this way, it is convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation to meet the requirements of radio frequency matching, which is beneficial to improving the bandwidth and reducing the power consumption, reducing the reflection during the transmission of electrical signals, and thus improving the electro-optical modulation performance.

[0007] In some possible embodiments, in a plane including a first direction and a second direction, the cross-section of any auxiliary electrode in the first modulation region is different from the cross-section of any auxiliary electrode in the second modulation region, so that the structure of the auxiliary electrodes in each modulation region can be flexibly designed, expanding the implementation modes of the solution.

[0008] In some possible embodiments, the structural features of any auxiliary electrode in the first modulation region in the first direction are different from the structural features of any auxiliary electrode in the second modulation region in the first direction, and / or the structural features of any auxiliary electrode in the first modulation region in the second direction are different from the structural features of any auxiliary electrode in the second modulation region in the second direction. That is to say, in at least one direction parallel and perpendicular to the waveguide extension direction, the structural features of the auxiliary electrodes have a greater impact on the radio frequency characteristic parameters of the modulation region, and it is more convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation to meet the requirements of both high bandwidth and radio frequency matching.

[0009] In some possible embodiments, each auxiliary electrode 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. This embodiment provides a structure of a T-shaped auxiliary electrode, which is beneficial to the modulation performance of the electro-optical modulator.

[0010] In some possible embodiments, the length of the first electrode structure of any auxiliary electrode in the first modulation region in the first direction is different from the length of the first electrode structure of any auxiliary electrode in the second modulation region in the first direction, and / or the length of the second electrode structure of any auxiliary electrode in the first modulation region in the second direction is different from the length of the second electrode structure of any auxiliary electrode in the second modulation region 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 an obvious impact on the radio frequency characteristic parameters of the modulation region, and it is more convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation to meet the requirements of both high bandwidth and radio frequency matching.

[0011] In some possible embodiments, the lengths of the first electrode structures of each auxiliary electrode in the same modulation region are the same in the first direction, and the lengths of the second electrode structures of each auxiliary electrode in the same modulation region are the same in the second direction. In the optical transmission direction, the lengths of the first electrode structures of the auxiliary electrodes in the plurality of modulation regions gradually increase in the first direction, and / or, in the optical transmission direction, the lengths of the second electrode structures of the auxiliary electrodes in the plurality of modulation regions gradually increase in the second direction. Through this design, the characteristic impedance of each modulation region along the optical transmission direction gradually decreases, which is beneficial to achieving radio frequency matching.

[0012] In some possible embodiments, the variation amplitudes of the lengths of the first electrode structures of the auxiliary electrodes in each adjacent two modulation regions are the same in the first direction, and / or, the variation amplitudes of the lengths of the second electrode structures of the auxiliary electrodes in each adjacent two modulation regions are the same in the second direction. That is to say, the variation amplitudes of the structural characteristics of the auxiliary electrodes in each two consecutive modulation regions remain consistent, which is beneficial to reducing the reflection formed during the transmission of the electrical signal, ensuring that the transmission speed of the electrical signal remains unchanged, and improving the modulation performance.

[0013] 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 region is different from the distance between the two first electrode structures of any auxiliary electrode in the second modulation region. It should be understood that for an electro-optic 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 strength, and thus have a greater impact on the modulation effect. Therefore, another structure of the auxiliary electrode is provided here. It is considered to change the radio frequency characteristic parameters of the modulation region 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 radio frequency characteristic parameters of each modulation region according to the actual situation to simultaneously meet the requirements of high bandwidth and radio frequency matching.

[0014] In some possible embodiments, the distance between the two first electrode structures of each auxiliary electrode in the same modulation region is the same, and in the optical transmission direction, the distance between the two first electrode structures of the auxiliary electrodes in the plurality of modulation regions gradually increases, so that the characteristic impedance of each modulation region along the optical transmission direction gradually decreases, which is beneficial to achieving radio frequency matching.

[0015] In some possible embodiments, the variation amplitude of the distance between the two first electrode structures of the auxiliary electrodes in each adjacent two modulation regions is the same, which is beneficial to reducing the reflection formed during the transmission of the electrical signal, ensuring that the transmission speed of the electrical signal remains unchanged, and improving the modulation performance.

[0016] In some possible embodiments, the width of the first electrode structure of any auxiliary electrode in the first modulation region in the second direction is different from the width of the first electrode structure of any auxiliary electrode in the second modulation region in the second direction, and / or, the width of the second electrode structure of any auxiliary electrode in the first modulation region in the first direction is different from the width of the second electrode structure of any auxiliary electrode in the second modulation region in the first direction. This embodiment provides two other structural features of the auxiliary electrode that affect the radio frequency characteristic parameters, expanding the implementation manners of configuring the radio frequency characteristic parameters of each modulation region.

[0017] In some possible embodiments, the number of the first electrode structures of any auxiliary electrode in the first modulation region is different from the number of the first electrode structures of any auxiliary electrode in the second modulation region. While ensuring the modulation effect, it is convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation, so as to simultaneously meet the requirements of high bandwidth and radio frequency matching.

[0018] In some possible embodiments, each auxiliary electrode further 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 region in the second direction is different from the length of the third electrode structure of any auxiliary electrode in the second modulation region in the second direction, and / or, the width of the third electrode structure of any auxiliary electrode in the first modulation region in the first direction is different from the width of the third electrode structure of any auxiliary electrode in the second modulation region 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 region is different from the distance between the second electrode structure and the third electrode structure of any auxiliary electrode in the second modulation region. This embodiment provides another structure of the auxiliary electrode, enhancing the scalability of the present solution. While ensuring the modulation effect, it is convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation, so as to simultaneously meet the requirements of high bandwidth and radio frequency matching.

[0019] In some possible embodiments, the spacing between any two adjacent auxiliary electrodes in the first modulation region is different from the spacing between any two adjacent auxiliary electrodes in the second modulation region. In the scenario where there are multiple auxiliary electrodes in the modulation region, the radio frequency characteristic parameters of the modulation region can also be changed by changing the spacing between two adjacent auxiliary electrodes, and the practical effect is good.

[0020] In some possible embodiments, the width of the main electrode in the first direction is gradually changed. By changing the width of the main electrode in the first direction, the radio frequency characteristic parameters of the modulation region can also be changed, improving the flexibility of the present solution. Moreover, the width transition of the main electrode is smoother, which can more effectively avoid reflection during the transmission of electrical signals, being beneficial to improving the modulation performance.

[0021] In some possible embodiments, the electro-optical 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 in the 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. The electrode located on one side of the first waveguide is connected to the first P-type doped region through the first P-type doped structure, and 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 doped 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 doped 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 doped structure. This embodiment provides a structure of a silicon optical modulator, expanding the types of electro-optical modulators adaptable to this solution.

[0022] In some possible embodiments, the distance between the first P-type doped region and the first N-type doped region in the first modulation region is different from the distance between the first P-type doped region and the first N-type doped region in the second modulation region, and the distance between the second P-type doped region and the second N-type doped region in the first modulation region is different from the distance between the second P-type doped region and the second N-type doped region in the second modulation region. In this embodiment, it is convenient to adjust the structural characteristics of the P-type doped regions and N-type doped regions in each modulation region according to the actual situation, which is beneficial to reducing the loss caused by the increase of the electrical signal with the transmission distance. It can not only increase the bandwidth but also maintain a high modulation efficiency.

[0023] In some possible embodiments, in the plane where the first direction and the second direction are located, the relative cross-sectional size ratio of the first P-type doped region and the first N-type doped region in the first modulation region is different from the relative cross-sectional size ratio of the first P-type doped region and the first N-type doped region in the second modulation region, and the relative cross-sectional size ratio of the second P-type doped region and the second N-type doped region in the first modulation region is different from the relative cross-sectional size ratio of the second P-type doped region and the second N-type doped region in the second modulation region. Another specific implementation method for adjusting the structural characteristics of the P-type doped regions and N-type doped regions in each modulation region is provided in this embodiment, which is beneficial to reducing the loss caused by the increase of the electrical signal with the transmission distance. It can not only increase the bandwidth but also maintain a high modulation efficiency.

[0024] In some possible embodiments, the doping concentration of the first P-type doped region in the first modulation region is different from that of the first P-type doped region in the second modulation region, and / or the doping concentration of the first N-type doped region in the first modulation region is different from that of the first N-type doped region in the second modulation region. The doping concentration of the second P-type doped region in the first modulation region is different from that of the second P-type doped region in the second modulation region, and / or the doping concentration of the second N-type doped region in the first modulation region is different from that of the second N-type doped region in the second modulation region. Another specific implementation manner for adjusting the structural characteristics of the P-type doped regions and N-type doped regions in each modulation region is provided in the embodiments, which is beneficial to reducing the loss caused by the increase of the electrical signal with the transmission distance, can not only improve the bandwidth, but also maintain a high modulation efficiency.

[0025] In some possible embodiments, the multiple electrodes include a first electrode, a second electrode, and a third electrode. The first waveguide is located between the first electrode and the second electrode, and the second waveguide is located between the second electrode and the third electrode. The first electrode and the third electrode are grounded, and the second electrode is loaded with an electrical signal. That is to say, this embodiment adopts a GSG-type electrode design, and the practical effect is good.

[0026] In some possible embodiments, 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 electrode and the second electrode, and the second waveguide is located between the third electrode and the fourth electrode. The first electrode and the fourth electrode are grounded, and the second electrode and the third electrode are respectively loaded with differential electrical signals. That is to say, this embodiment adopts a GSSG-type electrode design, which expands the applicable scenarios of this solution.

[0027] In some possible embodiments, 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.

[0028] In some possible embodiments, the multiple electrodes further include a fifth electrode. The fifth electrode is located between the second electrode and the third electrode, and the fifth electrode is grounded. That is to say, this embodiment adopts a GSGSG-type electrode design, which expands the applicable scenarios of this solution.

[0029] In some possible embodiments, the electro-optic modulator further includes a beam splitting module and a beam combining module. The two ends of the first waveguide are respectively connected to the beam splitting module and the beam combining module, and the two ends of the second waveguide 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 the first waveguide and the second waveguide respectively. The beam combining module is used to combine the light transmitted by the first waveguide and the light transmitted by the second waveguide.

[0030] Second aspect, embodiments of the present application provide an electro-optic modulator. The electro-optic modulator includes: a first waveguide, a second waveguide, and a plurality of electrodes. The first waveguide and the second waveguide are used for transmitting light, and the plurality of electrodes are used for transmitting 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 both sides of the second waveguide along a first direction. The first waveguide, the second waveguide, and the electrodes extend in a second direction, and the first direction is perpendicular to the second direction. The electro-optic modulator further includes 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 that extend in the second direction. The first waveguide includes a first P-type doping region and a first N-type doping region, and the second waveguide includes a second P-type doping region and a second N-type doping region; the electrodes located on one side of the first waveguide are connected to the first P-type doping region through the first P-type doping structure, and the electrodes located on the other side of the first waveguide are connected to the first N-type doping region through the first N-type doping structure. The electrodes located on one side of the second waveguide are connected to the second P-type doping region through the second P-type doping structure, and the electrodes located on the other side of the second waveguide are connected to the second N-type doping region through the second N-type doping structure. In the second direction, the structural characteristics of the first P-type doping region and / or the first N-type doping region are variable, and the structural characteristics of the second P-type doping region and / or the second N-type doping region are variable. It should be understood that flexibly adjusting the structural characteristics of the P-type doping region and the N-type doping region according to the actual situation is beneficial to reducing the loss caused by the increase of the electrical signal with the transmission distance, which can not only increase the bandwidth but also maintain high modulation efficiency.

[0031] In some possible implementation manners, in the second direction, the distance between the first P-type doping region and the first N-type doping region is variable, and the distance between the second P-type doping region and the second N-type doping region is variable.

[0032] In some possible implementation manners, 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 doping region and the first N-type doping region varies 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 varies along the second direction.

[0033] In some possible implementation manners, in the second direction, the doping concentration of the first P-type doping region is variable and / or the doping concentration of the first N-type doping region is variable. In the second direction, the doping concentration of the second P-type doping region is variable and / or the doping concentration of the second N-type doping region is variable.

[0034] In a third aspect, an embodiment of the present application provides an electro-optic modulator. The electro-optic 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 both sides of the second waveguide along a first direction. The first waveguide, the second waveguide, and the electrodes extend in a second direction, and the first direction is perpendicular to the second direction. The width of the main electrode is gradually changed in the first direction. By changing the width of the main electrode in the first direction, the radio frequency characteristic parameters of the modulation region can also be changed, improving the flexibility of the present solution. Moreover, the width transition of the main electrode is smoother, which can more effectively avoid reflection during the transmission of electrical signals and is beneficial to improving the modulation performance.

[0035] In a fourth aspect, an embodiment of the present application provides an optical chip. The optical chip includes a coupler, a waveguide, and an electro-optic modulator as introduced in any one of the first to third aspects. The coupler is used to couple the light from the laser to the waveguide, and the electro-optic modulator is used to modulate the light from the waveguide to obtain an optical signal.

[0036] In a fifth aspect, an embodiment of the present application provides an optical module. The optical module includes: at least one laser, a driver, and at least one electro-optic modulator as introduced in any one of the first to third aspects. The at least one laser is used to emit light. The driver is used to drive the at least one electro-optic modulator to modulate the light from the laser to obtain an optical signal.

[0037] In some possible implementation manners, the optical module includes a plurality of lasers and a plurality of electro-optic modulators, and the optical module further includes a wavelength division multiplexer. The wavelength division multiplexer is used to multiplex the optical signals output by the plurality of electro-optic modulators and output the multiplexed optical signal.

[0038] In a sixth aspect, an embodiment of the present application provides an optical communication system. The optical communication system includes a first communication device and a second communication device. Both the first communication device and the second communication device include an optical module as introduced in the fourth aspect. The first communication device and the second communication device are used to transmit optical signals therebetween.

[0039] In the embodiments of the present application, electrodes are distributed on both sides of the waveguide of the electro-optic modulator. Among them, the electrodes include a main electrode having the same extending direction as the waveguide and an auxiliary electrode extending from the main electrode and facing the waveguide. In the extending direction of the waveguide, the electro-optic modulator is divided into multiple modulation regions. In at least one direction parallel and perpendicular to the extending direction of the waveguide, the structural characteristics of the auxiliary electrodes in different modulation regions are different, so that the radio frequency characteristic parameters of different modulation regions are different. In this way, it is convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation to meet the requirements of radio frequency matching, reduce the occurrence of reflection during the transmission of electrical signals, and is beneficial to improving the bandwidth and reducing the power consumption, thereby improving the electro-optic modulation performance. Description of the Drawings

[0040] Fig. 1(a) is a schematic diagram of an optical fiber communication system;

[0041] Fig. 1(b) is a schematic structural diagram of an optical chip in the embodiments of the present application;

[0042] Figure 2 Fig. is a schematic diagram of a scenario where an electrical chip drives an electro-optic modulator in the embodiments of the present application;

[0043] Figure 3 Fig. is the first schematic structural diagram of an electro-optic modulator in the embodiments of the present application;

[0044] Figure 4 Fig. is the second schematic structural diagram of an electro-optic modulator in the embodiments of the present application;

[0045] Figure 5 Fig. is the third schematic structural diagram of an electro-optic modulator in the embodiments of the present application;

[0046] Figure 6 Fig. is the fourth schematic structural diagram of an electro-optic modulator in the embodiments of the present application;

[0047] Figure 7 Fig. is the first schematic structural diagram of an auxiliary electrode in the embodiments of the present application;

[0048] Figure 8 Fig. is the second schematic structural diagram of an auxiliary electrode in the embodiments of the present application;

[0049] Figure 9 Fig. is the fifth schematic structural diagram of an electro-optic modulator in the embodiments of the present application;

[0050] Figure 10 Fig. is the sixth schematic structural diagram of an electro-optic modulator in the embodiments of the present application;

[0051] Figure 11 Fig. is the third schematic structural diagram of an auxiliary electrode in the embodiments of the present application;

[0052] Figure 12 This is the fourth structural schematic diagram of the auxiliary electrode in the embodiment of the present application;

[0053] Figure 13 This is the seventh structural schematic diagram of the electro-optic modulator in the embodiment of the present application;

[0054] Figure 14 This is the eighth structural schematic diagram of the electro-optic modulator in the embodiment of the present application;

[0055] Figure 15 This is the ninth structural schematic diagram of the electro-optic modulator in the embodiment of the present application. Specific implementation manners

[0056] The embodiment of the present application provides an electro-optic modulator, an optical module, and an optical chip, which facilitate flexibly configuring the radio frequency characteristic parameters of each modulation region in the electro-optic modulator according to the actual situation to meet the requirements of radio frequency matching, reduce the occurrence of reflection during the transmission of electrical signals, and are beneficial to improving the bandwidth and reducing the power consumption, thereby improving the electro-optic modulation performance.

[0057] It should be noted that the terms "first", "second", etc. (if any) in the description, claims, and above-mentioned drawings of the present application are used to distinguish similar objects and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments described here can be implemented in an order different from that illustrated or described here. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device including a series of steps or units does not necessarily need to be limited to those clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0058] Figure 1(a) is a schematic diagram of an optical fiber communication system. As shown in Figure 1(a), the transmitter includes an electrical chip, a laser, a modulator, a wavelength division multiplexer, etc. The transmitter is used to convert electrical signals into optical signals. Among them, the laser is used to emit laser light. The electrical chip is used to output an electrical signal to the modulator to drive the modulator to modulate the laser light emitted by the laser to obtain an optical signal. This electrical chip can also be called a "driver". Optionally, in the scenario of multiple optical signals, the wavelength division multiplexer is used to multiplex optical signals of different wavelengths and couple the multiplexed optical signals into an optical fiber for transmission. The receiver includes a wavelength division demultiplexer, a detector, an electrical chip, etc. The receiver is used to convert optical signals into electrical signals. Among them, the wavelength division demultiplexer is used to separate optical signals of different wavelengths and output them to different detectors respectively, and the electrical chip is used to drive the detector to convert the optical signal into an electrical signal. It should be understood that the modulator is mainly applied in the transmitter of the optical fiber communication system. This modulator can specifically be an electro-optic modulator, for example, a Mach-Zehnder Modulator (MZM), etc. By external modulation, an electrical signal is loaded onto an optical carrier to change the characteristics of the optical signal, such as phase or intensity, etc., so as to realize the conversion of electrical signals into optical signals. It should also be understood that the above-mentioned transmitter can be understood as the optical transmission unit in the optical module, and the above-mentioned receiver can be understood as the optical reception unit in the optical module.

[0059] Figure 1(b) is a schematic structural diagram of an optical chip in an embodiment of the present application. As shown in Figure 1(b), this optical chip includes a coupler, a waveguide, and an electro-optic modulator. The coupler is used to couple the light from the laser into the waveguide and transmit it to the electro-optic modulator through the waveguide. The electro-optic modulator modulates the light from the waveguide according to the radio frequency signal from the electrical chip to obtain an optical signal and outputs it.

[0060] Figure 2 This is a schematic diagram of a scenario where an electrical chip drives an electro-optic modulator in an embodiment of the present application. As Figure 2As shown, one end of the electrode in the electro-optic modulator is connected to the resistor Rs in the electrical chip, and the other end of the electrode in the electro-optic modulator is connected to the 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 the radio frequency matching, usually Rs = Z = Rt. However, for the current mainstream electrical chips, the value of Rs is usually 50 Ohm, and for common silicon optical modulators, the value of Z is usually 30 Ohm, and there is a large difference between the two. At this time, if Rs = Z = Rt = 50 Ohm, although the radio frequency matching and low power consumption characteristics can be satisfied, it is difficult to achieve a high modulation bandwidth. If Rs = Z = Rt = 30 Ohm, although the radio frequency matching and high bandwidth characteristics can be satisfied, it is difficult to achieve low power consumption. If Rs = Z ≠ Rt, at this time, the bandwidth and power consumption performance can be improved, but the radio frequency matching requirement is not met, which will cause problems such as reflection in the transmission of electrical signals in the electro-optic modulator, resulting in poor electro-optic modulation performance. That is to say, when the characteristic impedance Z of the electro-optic modulator takes a single fixed value, no matter how Rs and Rt are valued, it is difficult to simultaneously meet the radio frequency matching, high bandwidth and low power consumption characteristics.

[0061] Therefore, the electro-optic modulator provided in this application is divided into multiple modulation regions, and the structural characteristics in different modulation regions can be different, so that the radio frequency characteristic parameters (including characteristic impedance and microwave refractive index, etc.) of different modulation regions are different. In this way, it is convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation to meet the requirements of radio frequency matching, reduce the occurrence of reflection during the transmission of electrical signals, and is beneficial to improving the bandwidth and reducing the power consumption, thereby improving the electro-optic modulation performance. For example, the radio frequency characteristic parameters of the modulation region close to Rs are different from those of the modulation region close to Rt. By reasonably designing Rs, Rt and the radio frequency characteristic parameters of each modulation region, both the high bandwidth and low power consumption characteristics of the electro-optic modulator can be ensured, and the radio frequency matching with the electrical chip can also be achieved.

[0062] Figure 3 This is the first structural schematic diagram of the electro-optic modulator in the embodiment of this application. As Figure 3 shown, the electro-optic modulator includes a beam splitting module, a beam combining module, waveguide 1 and waveguide 2. Both ends of waveguide 1 are respectively connected to the beam splitting module and the beam combining module, and both 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 adopt other electro-optic materials similar to LN such as Lithium Niobate (LN), silicon, silicon nitride or barium titanate (BaTiO3), and specific details are not limited here.

[0063] It should be noted that electro-optic modulators can generally be classified into silicon optical modulators and electro-optic material modulators according to the materials used in the waveguides. Among them, 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, etc. 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 include a doping structure. The different structures of silicon optical modulators and electro-optic material modulators will be introduced below.

[0064] Figure 4 This is the second structural schematic diagram of the electro-optic modulator in the embodiments of the present application. As Figure 4 shown, 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. A plurality of electrodes are distributed on both sides of waveguide 1 and waveguide 2 along the Y direction, where the X direction and the Y direction are perpendicular to each other. As an example, a GSSG-type electrode structure is adopted. 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 respectively loaded with differential electrical signals S+ and S-. 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.

[0065] Figure 5 This is the third structural schematic diagram of the electro-optic modulator in the embodiments of the present application. As Figure 5As shown in the figure, this is a side cross-sectional view of a silicon optical modulator, where 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 through an N-type doping structure, and the N-type doping 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 through a P-type doping structure, and the P-type doping 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 through the N-type doping structure, and the electrical signal loaded on electrode 2 is conducted to the P-type doped region of waveguide 1 through the P-type doping structure. In some other possible scenarios, it can also be that electrode 1 is connected to the P-type doped region in waveguide 1 through a P-type doping structure, and electrode 2 is connected to the N-type doped region in waveguide 1 through an N-type doping structure. It should be understood that the present application does not limit the doping concentration 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.

[0066] Figure 6 This is the fourth schematic structural diagram of the electro-optic modulator in the embodiments of the present application. As Figure 6 shown, this is a top view of an electro-optic material modulator. Different from the Figure 4 and Figure 5 silicon optical modulator shown, the electro-optic material modulator does not have a P-type doping structure and an N-type doping structure, nor does the waveguide have a P-type doped region and an N-type doped region. As an example, a GSG-type electrode structure is adopted. Electrode 1 and electrode 2 are distributed on both sides of waveguide 1, electrode 2 and electrode 3 are 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. Additionally, Figure 4 and Figure 5 the electrodes in the silicon optical modulator shown are mainly used for conducting electricity, while the electrodes in the Figure 6 electro-optic material modulator shown are used to form an electric field. For example, Figure 6 in, 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 external electric field is applied to waveguide 1, due to the linear electro-optic effect of the electro-optic material, the refractive index of the material of waveguide 1 can change, and this change can change the propagation characteristics of light in the waveguide, such as the phase, amplitude, or polarization of light, etc., so as to realize the modulation of the light transmitted in the waveguide.

[0067] It should be understood that the present application does not limit the electrode design method adopted by the electro-optic modulator. In addition to the above-mentioned GSG-type electrode structure, GSSG-type electrode structure, and GSGSG-type electrode structure, in some possible implementation manners, only 2 electrodes may also be designed, and both waveguide 1 and waveguide 2 are located between these 2 electrodes. No drawings are provided here for illustration.

[0068] It should be noted that the electro-optic modulator divides different modulation regions according to the different structural characteristics of the electrodes in the modulation region, that is, the structural characteristics of the electrodes in adjacent two modulation regions are different, and each modulation region is distributed along the extension direction of waveguide 1 and waveguide 2. The following will be introduced in detail in combination with the structural characteristics of the electrodes.

[0069] Specifically, each electrode is composed of a main electrode and an auxiliary electrode connected to the main electrode. Among them, the main electrode is in the same direction as the extension direction of the waveguide, and the auxiliary electrode extends towards the position where the waveguide is located. The auxiliary electrode is designed to optimize the modulation performance. Figure 4 Taking [example] as an example, the auxiliary electrode is of a T-shaped structure. The auxiliary electrodes on electrodes 1 and 2 on both sides of waveguide 1 extend towards waveguide 1, and the auxiliary electrodes on electrodes 3 and 4 on both sides of waveguide 2 extend towards waveguide 2.

[0070] Figure 7 This is the first structural schematic diagram of the auxiliary electrode in the embodiment of the present application. It should be understood that the auxiliary electrode provided by the present application is not limited to Figure 5 the T-shaped structure shown. For the convenience of introduction, the part of the auxiliary electrode extending along the Y direction is called electrode structure 1 here, and the part of the auxiliary electrode extending along the X direction is called electrode structure 2. As long as the auxiliary electrode structure has electrode structure 1 and electrode structure 2, it is within the protection scope of the present 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.

[0071] It should be noted that the present application specifically divides different modulation regions according to the different structural characteristics of the auxiliary electrodes, and the present application does not limit the number of auxiliary electrodes in each modulation region. For example, the number of auxiliary electrodes in each modulation region may be the same; or for another example, the number of auxiliary electrodes in different modulation regions may also be different. That is to say, each auxiliary electrode in the same modulation region has the same structural characteristics, while the structural characteristics of the auxiliary electrodes in adjacent two modulation regions are different. It should be understood that the present application does not limit the number of modulation regions and the length of each modulation region in the X direction. For example, 5 modulation regions are provided, and the length of each modulation region in the X direction is 400um.

[0072] It should also be noted that any parameter that can reflect the structure of the auxiliary electrode can be regarded as a structural feature of the auxiliary electrode. The structural features of the auxiliary electrode include, but are not limited to, the shape and size of the auxiliary electrode, etc. As an example, the shapes of the auxiliary electrodes in adjacent modulation regions are different. For example, Figure 8 the change in the distance gh between the two electrode structures 1 in Figure 10 can be regarded as a different shape of the auxiliary electrode; another example is that Figure 7 and Figure 11 any parameter change marked in

[0073] can be regarded as a different size. As another example, the shapes of the auxiliary electrodes in adjacent modulation regions are different and the sizes are also different. In other words, the cross-section of the auxiliary electrode shown in the plane formed by the above 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 regions can also be reflected as different cross-sections of the auxiliary electrodes in adjacent modulation regions, including but not limited to different cross-section shapes and different cross-section sizes.

[0074] Taking adjacent modulation region 1 and modulation region 2 as an example, the different structural features of the auxiliary electrodes in these two modulation regions satisfy at least one of the following conditions: 1. The structural features of the auxiliary electrode in modulation region 1 in the X direction are different from the structural features of the auxiliary electrode in modulation region 2 in the X direction; 2. The structural features of the auxiliary electrode in modulation region 1 in the Y direction are different from the structural features of the auxiliary electrode in modulation region 2 in the Y direction. It should be understood that in the plane formed by the above X direction and Y direction, the structure of the auxiliary electrode is split into electrode structure 1 extending along the Y direction and electrode structure 2 extending along the X direction. That is, 1. The structural parameters of electrode structure 1 in adjacent modulation regions are different; 2. The structural parameters of electrode structure 2 in adjacent modulation regions are different. The following will be introduced separately in combination with some specific design methods.

[0075] In a possible implementation manner, the structural size of electrode structure 1 of the auxiliary electrode in modulation region 1 is different from the structural size of electrode structure 1 of the auxiliary electrode in modulation region 2, and / or, the structural size of electrode structure 2 of the auxiliary electrode in modulation region 1 is different from the structural size of electrode structure 2 of the auxiliary electrode in modulation region 2. Specifically, taking Figure 7 as an example, the length of electrode structure 1 of the auxiliary electrode in the Y direction is denoted as Wh, the width of electrode structure 1 of the auxiliary electrode in the X direction is denoted as Lh, the length of electrode structure 2 of the auxiliary electrode in the X direction is denoted as Ls, and the width of electrode structure 2 of the auxiliary electrode in the Y direction is denoted as Ws.

[0076] As a first example, the length Wh-1 of the electrode structure 1 of the auxiliary electrode in modulation region 1 is different from the length Wh-2 of the electrode structure 1 of the auxiliary electrode in modulation region 2. In one possible scenario, as Figure 4 shown, along the X direction from modulation region 1 to modulation region n, the length Wh of the electrode structure 1 of the auxiliary electrode gradually increases, i.e., Wh-1 < Wh-2 <... < Wh-n, and the characteristic impedance of each modulation region gradually decreases, such that the characteristic impedance of modulation region 1 is close to the resistance Rs, and the characteristic impedance of modulation region n is close to the resistance Rt, which is beneficial to achieving radio frequency matching.

[0077] As a second example, the width Lh-1 of the electrode structure 1 of the auxiliary electrode in modulation region 1 is different from the width Lh-2 of the electrode structure 1 of the auxiliary electrode in modulation region 2. In one possible scenario, as Figure 6 shown, along the X direction from modulation region 1 to modulation region n, the width Lh of the electrode structure 1 of the auxiliary electrode gradually increases, i.e., Lh-1 < Lh-2 <... < Lh-n, and the characteristic impedance of each modulation region gradually decreases, such that the characteristic impedance of modulation region 1 is close to the resistance Rs, and the characteristic impedance of modulation region n is close to the resistance Rt, which is beneficial to achieving radio frequency matching.

[0078] As a third example, the length Ls-1 of the electrode structure 2 of the auxiliary electrode in modulation region 1 is different from the length Ls-2 of the electrode structure 2 of the auxiliary electrode in modulation region 2. In one possible scenario, along the X direction from modulation region 1 to modulation region n, the length Ls of the electrode structure 2 of the auxiliary electrode gradually increases, i.e., Ls-1 < Ls-2 <... < Ls-n, which is beneficial to improving the modulation efficiency.

[0079] As a fourth example, the width Ws-1 of the electrode structure 2 of the auxiliary electrode in modulation region 1 is different from the width Ws-2 of the electrode structure 2 of the auxiliary electrode in modulation region 2. In one possible scenario, along the X direction from modulation region 1 to modulation region n, the width Ws of the electrode structure 2 of the auxiliary electrode gradually decreases, i.e., Ws-1 > Ws-2 >... > Ws-n, which helps to achieve a smoother transition.

[0080] As a fifth example, in the 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 modulation region 2. For example Figure 7 shown, this spacing can be the spacing p between two adjacent electrode structures 2. Alternatively, this spacing can be the spacing between two adjacent electrode structures 1.

[0081] It should be understood that the above five examples can also be combined in any way, and will not be listed one by one here. It should also be understood that for the above five examples, the gradual change trend of the structural characteristic parameters of the auxiliary electrode is not limited, and it is possible to gradually increase, gradually decrease, or alternately increase and decrease.

[0082] It should be noted that for the above Figure 6 shown electro-optic material modulator, the T-shaped auxiliary electrode is used to form an electric field. The length Wh of the electrode structure 1 of the auxiliary electrode in the Y direction and the length Ls of the electrode structure 2 of the auxiliary electrode in the X direction have a greater impact on the electric field strength, and thus have a greater impact on the modulation effect. Usually, in the electro-optic material modulator, these two parameters Wh and Ls are set to fixed values. In addition, other structural characteristic parameters of the auxiliary electrode vary in different modulation regions.

[0083] Figure 8 This is the second schematic diagram of the structure of the auxiliary electrode in the embodiment of the present application. Different from the Figure 7 shown auxiliary electrode, as Figure 8 shown, each auxiliary electrode includes a plurality of electrode structures 1 extending in 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 region 1 is different from the distance gh-2 between two adjacent electrode structures 1 of the auxiliary electrode in modulation region 2.

[0084] Figure 9 This is the fifth schematic diagram of the structure of the electro-optic modulator in the embodiment of the present application. As Figure 9 shown, in a possible scenario, along the X direction from modulation region 1 to modulation region 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 region gradually decreases, so that the characteristic impedance of modulation region 1 is close to the resistance Rs, and the characteristic impedance of modulation region n is close to the resistance Rt, which is beneficial to achieving radio frequency matching.

[0085] Figure 10 This is the sixth schematic diagram of the structure of the electro-optic modulator in the embodiment of the present application. As Figure 10 shown, in a possible scenario, the number of electrode structures 1 of the auxiliary electrode in modulation region 1 is different from the number of electrode structures 1 of the auxiliary electrode in modulation region 2. For example, along the X direction from modulation region 1 to modulation region n, the number of electrode structures 1 of the auxiliary electrode gradually increases, and the characteristic impedance of each modulation region gradually decreases, so that the characteristic impedance of modulation region 1 is close to the resistance Rs, and the characteristic impedance of modulation region n is close to the resistance Rt, which is beneficial to achieving radio frequency matching.

[0086] Figure 11This is the third schematic diagram of the auxiliary electrode in the embodiments of the present application. Different from Figure 7 the auxiliary electrode shown in Figure 11 as shown, the auxiliary electrode further includes an electrode structure 3 extending in the X direction. The electrode structure 3 is connected to the electrode structure 1, and the electrode structure 3 is located between the electrode structure 2 and the main electrode. Denote the length of the electrode structure 3 of the auxiliary electrode in the X direction as Lstu, the width of the electrode structure 3 of the auxiliary electrode in the Y direction as Wstu, and the distance between the electrode structure 2 and the electrode structure 3 as Whtu.

[0087] As an example, the length Lstu-1 of the electrode structure 3 of the auxiliary electrode in the modulation region 1 is different from the length Lstu-2 of the electrode structure 2 of the auxiliary electrode in the modulation region 2. In a possible scenario, along the X direction from the modulation region 1 to the modulation region 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 beneficial to improving the modulation efficiency.

[0088] As another example, the width Wstu-1 of the electrode structure 3 of the auxiliary electrode in the modulation region 1 is different from the width Wstu-2 of the electrode structure 2 of the auxiliary electrode in the modulation region 2. In a possible scenario, along the X direction from the modulation region 1 to the modulation region n, the width Wstu of the electrode structure 3 of the auxiliary electrode gradually decreases, that is, Wstu-1 > Wstu-2 >... > Wstu-n, which helps to achieve a smoother transition.

[0089] As yet another example, the distance Whtu-1 between the electrode structure 2 and the electrode structure 3 of the auxiliary electrode in the modulation region 1 is different from the distance Whtu-2 between the electrode structure 2 and the electrode structure 3 of the auxiliary electrode in the modulation region 2. In a possible scenario, along the X direction from the modulation region 1 to the modulation region 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 beneficial to improving the modulation efficiency.

[0090] It should be understood that the above three examples can also be combined in any way, and will not be listed one by one here. 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 it is possible to gradually increase, gradually decrease, or alternately increase and decrease.

[0091] In some possible embodiments, the width of the main electrode in the Y direction is gradually changed. By changing the width of the main electrode in the first direction, the radio frequency characteristic parameters of the modulation region can also be changed, which improves the flexibility of the present solution. Moreover, the width transition of the main electrode is smoother, which can more effectively avoid reflection during the transmission of electrical signals and is beneficial to improving the modulation performance. For example, the width of the main electrode gradually becomes wider along the X direction. Specifically, the width of the main electrode can gradually change towards both sides; or, one side of the main electrode remains unchanged, and the other side gradually changes to make the width gradually change.

[0092] In some possible embodiments, for the structural feature changes of the auxiliary electrodes in different modulation regions introduced in any of the above embodiments, along the X direction from modulation region 1 to modulation region n, the change amplitude of the structural features of the auxiliary electrodes in every two consecutive modulation regions remains the same, which is beneficial to reducing the reflection formed during the transmission of electrical signals, ensuring that the transmission speed of the electrical signals remains unchanged, and improving the modulation performance. Taking the length Wh-1 of the electrode structure 1 of the above auxiliary electrode as an example, Wh-2 - Wh-1 = Wh-3 - Wh-2 =... = Wh-n - Wh-n-1. In addition, other characteristic parameters of the above-mentioned auxiliary electrodes are similar, and will not be elaborated one by one here.

[0093] Figure 12 This is the fourth structural schematic diagram of the auxiliary electrode in the embodiment of the present application. It should be understood that in addition to the structures of the auxiliary electrodes introduced in the above embodiments, the auxiliary electrodes can also adopt other structural designs, as long as the auxiliary electrodes have the electrode structure 1 extending in the Y direction and the electrode structure 2 extending in the X direction. For example Figure 12 As shown, the auxiliary electrode can also adopt an L-shaped structure or a Z-shaped structure.

[0094] It should be noted that for the Figure 4 and Figure 5 silicon optical modulators shown, in addition to the structural features of the electrodes affecting the radio frequency characteristic parameters of the modulation region, the characteristics of the P-type doped region and the N-type doped region will also affect the radio frequency characteristic parameters, modulation efficiency, and modulation bandwidth. Therefore, the characteristics of the P-type doped region and the N-type doped region in different modulation regions can also be different, so that the capacitance and resistance values of different modulation regions are different, thereby affecting the radio frequency characteristic parameters. It is convenient to flexibly configure the radio frequency characteristic parameters of each modulation region according to the actual situation, which is beneficial to improving the overall bandwidth and reducing the occurrence of reflection during the transmission of electrical signals, thereby improving the electro-optic modulation performance. The characteristics of the P-type doped region and the N-type doped region will be introduced in detail below.

[0095] Figure 13 This is the seventh structural schematic diagram of the electro-optic modulator in the embodiment of the present application. As Figure 13As shown, taking the P-type doped region and the N-type doped region on both sides of waveguide 1 or waveguide 2 as an example, the distance between the P-type doped region and the N-type doped region in modulation region 1 is different from the distance between the P-type doped region and the N-type doped region in modulation region 2. In one possible scenario, the distance between the P-type doped region and the N-type doped region can be gradually changed, that is, the distance between the P-type doped region and the N-type doped region within the same modulation region is also gradually changed. In another possible scenario, the distance between the P-type doped region and the N-type doped region can also change in a stepped manner, that is, the distance between the P-type doped region and the N-type doped region within each modulation region is the same, and the distance between the P-type doped region and the N-type doped region in different modulation regions is changed. As an example, along the X direction from modulation region 1 to modulation region n, the distance between the P-type doped region and the N-type doped region gradually increases, which can gradually reduce the capacitance value of the PN junction and reduce the loss caused by the increase of the electrical signal with the transmission distance, which can not only increase the bandwidth but also maintain a high modulation efficiency. It should be understood that the way in which the distance between the P-type doped region and the N-type doped region gradually increases can be a linear change or a non-linear change. If it is a linear change, it is beneficial to reduce the reflection formed by the electrical signal during transmission, ensure that the transmission speed of the electrical signal remains unchanged, and improve the modulation performance.

[0096] Figure 14 This is the eighth structural schematic diagram of the electro-optic modulator in the embodiment of the present application. As Figure 14 shown, the cross-section of the P-type doped region shown in the plane formed by the X direction and the Y direction can be called the cross-section of the P-type doped region, and the cross-section of the N-type doped region shown can be called the cross-section of the N-type doped region. Taking the P-type doped region and the N-type doped region on both sides of waveguide 1 or waveguide 2 as an example, the relative size ratio of the cross-sections of the P-type doped region and the N-type doped region in modulation region 1 is different from the relative size ratio of the cross-sections of the P-type doped region and the N-type doped region in modulation region 2. In one possible scenario, the relative size ratio of the cross-sections of the P-type doped region and the N-type doped region can be gradually changed, that is, the relative size ratio of the cross-sections of the P-type doped region and the N-type doped region within the same modulation region is also gradually changed. In another possible scenario, the relative size ratio of the cross-sections of the P-type doped region and the N-type doped region can also change in a stepped manner, that is, the relative size ratio of the cross-sections of the P-type doped region and the N-type doped region within each modulation region is the same, and the relative size ratio of the cross-sections of the P-type doped region and the N-type doped region in different modulation regions is changed. As an example, along the X direction from modulation region 1 to modulation region n, the proportion of the P-type doped region in each modulation region gradually increases, which is beneficial to improving the modulation efficiency. As another example, along the X direction from modulation region 1 to modulation region n, the proportion of the N-type doped region in each modulation region gradually increases, which is beneficial to increasing the modulation bandwidth.

[0097] Figure 15 This is the ninth structural schematic diagram of the electro-optic modulator in the embodiments of the present application. As Figure 15 shown, taking the P-type doping region and the N-type doping region on both sides of waveguide 1 or waveguide 2 as an example, the doping concentration of the P-type doping region in modulation region 1 is different from the doping concentration of the P-type doping region in modulation region 2, and / or the doping concentration of the N-type doping region in modulation region 1 is different from the doping concentration of the N-type doping region in modulation region 2. In a possible scenario, the doping concentrations of the P-type doping region and the N-type doping region can be gradually changed, that is, the doping concentrations of the P-type doping region and the N-type doping region in the same modulation region are also gradually changed. In another possible scenario, the doping concentrations of the P-type doping region and the N-type doping region can also change in a stepped manner, that is, the doping concentration of the P-type doping region in each modulation region is the same, the doping concentration of the N-type doping region in each modulation region is the same, the doping concentration of the P-type doping region in different modulation regions is changed, and the doping concentration of the N-type doping region in different modulation regions is changed. As an example, along the X direction from modulation region 1 to modulation region 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 beneficial to improving the modulation bandwidth.

[0098] It should be understood that any combination can be made between the embodiments with different structural features of the auxiliary electrode. The present application does not limit the change trend of the structural feature parameters of the auxiliary electrode with the arrangement of the modulation regions, and it can gradually increase, gradually decrease, or alternately increase and decrease. Any combination can also be made between the embodiments with different structural features of the P-type doping region and the N-type doping region. The present application does not limit the change trend of the structural feature parameters of the P-type doping region and the N-type doping region with the arrangement of the modulation regions, and it can gradually increase, gradually decrease, or alternately increase and decrease. Similarly, any combination can be made between 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, which will not be elaborated one by one here.

[0099] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An electro - optical modulator, characterized in that, Comprising: A first waveguide, a second waveguide, and a plurality of electrodes. The first waveguide and the second waveguide are used for transmitting light. The plurality of electrodes are distributed on both sides of the first waveguide and both sides of the second waveguide along a first direction. 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. The plurality of auxiliary electrodes are distributed along the second direction. The first direction is perpendicular to the second direction. The electro-optic modulator includes a plurality of modulation regions in the second direction. A first modulation region and a second modulation region are two adjacent modulation regions. The structural features of the auxiliary electrodes in the first modulation region are different from the structural features of the auxiliary electrodes in the second modulation region.

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

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

5. The electro - optical modulator according to claim 4, characterized in that, The lengths of the first electrode structures of each of the auxiliary electrodes in the same modulation region in the first direction are the same, and the lengths of the second electrode structures of each of the auxiliary electrodes in the same modulation region in the second direction are the same; In the light transmission direction, the lengths of the first electrode structures of the auxiliary electrodes in the plurality of modulation regions in the first direction gradually increase, and / or, in the light transmission direction, the lengths of the second electrode structures of the auxiliary electrodes in the plurality of modulation regions in the second direction gradually increase.

6. The electro - optical modulator according to claim 5, characterized in that, The variation amplitude of the lengths of the first electrode structures of the auxiliary electrodes in every two adjacent modulation regions in the first direction is the same, and / or, the variation amplitude of the lengths of the second electrode structures of the auxiliary electrodes in every two adjacent modulation regions in the second direction is the same.

7. The electro - optical 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. The distance between the two first electrode structures of any one of the auxiliary electrodes in the first modulation region is different from the distance between the two first electrode structures of any one of the auxiliary electrodes in the second modulation region.

8. The electro - optical modulator according to claim 7, characterized in that, The distances between the two first electrode structures of each of the auxiliary electrodes in the same modulation region are the same. In the light transmission direction, the distances between the two first electrode structures of the auxiliary electrodes in the plurality of modulation regions gradually increase.

9. The electro - optical modulator according to claim 8, characterized in that, The variation amplitude of the distances between the two first electrode structures of the auxiliary electrodes in every two adjacent modulation regions is the same.

10. The electro - optical 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 region in the second direction is different from the width of the first electrode structure of any auxiliary electrode in the second modulation region in the second direction, and / or the width of the second electrode structure of any auxiliary electrode in the first modulation region in the first direction is different from the width of the second electrode structure of any auxiliary electrode in the second modulation region in the first direction.

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

12. The electro - optical modulator according to any one of claims 3 to 11, characterized in that, Each of the auxiliary electrodes further 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 region in the second direction is different from the length of the third electrode structure of any auxiliary electrode in the second modulation region in the second direction, and / or the width of the third electrode structure of any auxiliary electrode in the first modulation region in the first direction is different from the width of the third electrode structure of any auxiliary electrode in the second modulation region 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 region is different from the distance between the second electrode structure and the third electrode structure of any auxiliary electrode in the second modulation region.

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

14. The electro - optical 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 - optical modulator according to any one of claims 1 to 14, characterized in that, The electro-optic modulator further includes 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 includes a first P-type doping region and a first N-type doping region, and the second waveguide includes 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 doping 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 doping 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 doping 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 doping region through the second N-type doping structure.

16. The electro - optical modulator according to claim 15, characterized in that, 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.

17. The electro - optical 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 cross-sectional size ratio of the first P-type doping region and the first N-type doping region in the first modulation region is different from the relative cross-sectional size ratio of the first P-type doping region and the first N-type doping region in the second modulation region, and the relative cross-sectional size ratio of the second P-type doping region and the second N-type doping region in the first modulation region is different from the relative cross-sectional size ratio of the second P-type doping region and the second N-type doping region in the second modulation region.

18. The electro-optical 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 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.

19. An optical module, characterized in that, Comprising: At least one laser, a driver, and at least one electro-optic modulator according to any one of claims 1 to 18; The at least one laser is configured to emit light; The driver is configured to drive the at least one electro-optic 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-optic modulators, and the optical module further includes a wavelength division multiplexer; The wavelength division multiplexer is configured to multiplex the optical signals output by the plurality of electro-optic modulators and output the multiplexed optical signal.

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

Images