Y-type thin-film lithium niobate electro-optical modulator and manufacturing method thereof

Abstract

According to the Y-type thin-film lithium niobate electro-optical modulator and the manufacturing method provided by the invention, the lithium niobate layer on the electro-optical modulator chip is etched into the corresponding bent waveguide structures, and the two bent waveguide structures are symmetrically arranged on the two sides of the Y-type waveguide structure, so that the height consistency of two optical paths is ensured; according to the bent waveguide structure, the length of the waveguide is guaranteed, meanwhile, the size of the space occupied by the waveguide is reduced, the waveguide with the same length can be carried by adopting a chip with smaller length, and meanwhile, the signal electrode and the ground electrode are arranged on the two sides of each section of straight waveguide in the bent waveguide structure, so that the size of the waveguide is reduced. The optical signal in the waveguide is modulated, and the modulation requirement of the electro-optical modulator is met.

Description

Technical Field

[0001] The invention belongs to the field of integrated optics, and in particular relates to a Y-type thin-film lithium niobate electro-optic modulator and a manufacturing method thereof. Background Art

[0002] Electro-optical modulation achieves long-distance, low-loss transmission of information by loading electrical signals onto optical signals, and is the foundation of modern communication networks. Thin-film lithium niobate materials, due to their combination of high integration and excellent electro-optic coefficients, can realize low-power, small-size electro-optical modulation devices, and have great potential in the field of electro-optical modulation. The thin-film lithium niobate structure currently used is generally an X-cut lithium niobate film, and the electrodes are generally distributed on both sides of the waveguide to achieve consistency between the electric field and the optical axis. At this time, the electro-optic coefficient is the largest and the modulation efficiency is high. The problem is that there are both optical and electrical structures arranged on the chip surface, and multiple crosstalk factors need to be considered, as well as the space occupied by the optical and electrical structures.

[0003] In view of this, overcoming the defects of the prior art is an urgent problem to be solved in the field of this technology. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to arrange the corresponding waveguide structure and electrodes on the electro-optic modulator, and reduce the occupied space of the waveguide structure and the electrodes under the premise that the direction of the electric field is consistent with the optical axis.

[0005] The present invention adopts the following technical solution:

[0006] In a first aspect, a Y-type thin film lithium niobate electro-optic modulator is provided, comprising: a lithium niobate layer 1, an electrode 2 and an oxide layer 3, wherein:

[0007] The lithium niobate layer 1 is disposed on the oxide layer 3;

[0008] The lithium niobate layer 1 includes a first Y-type waveguide structure 11 and two curved waveguide structures 12, wherein the two curved waveguide structures 12 are symmetrically arranged on both sides of the first Y-type waveguide structure 11 and connected to the first Y-type waveguide structure 11;

[0009] The curved waveguide structure 12 includes a plurality of straight waveguides 121 and a plurality of curved waveguides 122. The plurality of straight waveguides 121 are arranged in parallel with each other. Adjacent straight waveguides 121 are connected end to end through the curved waveguides 122, so that all straight waveguides 121 in the same curved waveguide structure 12 are connected in series.

[0010] The electrode 2 is located on the lithium niobate layer 1, and the electrode 2 includes a signal electrode 21 and a ground electrode 22. The ground electrode 22 and the signal electrode 21 are respectively arranged on both sides of each straight waveguide 121. The signal electrode 21 and the ground electrode 22 are respectively arranged parallel to the straight waveguide 121, so as to ensure that the direction of the electric field generated by the ground electrode 22 and the signal electrode 21 is perpendicular to the straight waveguide 121.

[0011] Preferably, the Y-type thin film lithium niobate electro-optic modulator further comprises: a substrate 4 and a buffer layer 5, wherein:

[0012] The substrate 4 is located below the oxide layer 3;

[0013] The buffer layer 5 is disposed between the lithium niobate layer 1 and the electrode 2 .

[0014] Preferably, the first Y-type waveguide structure 11 comprises a first trunk waveguide 111 and two first branch waveguides 112, wherein:

[0015] The first trunk waveguide 111 and the two first branch waveguides 112 are respectively connected;

[0016] One of the first branch waveguides 112 is connected to one of the curved waveguide structures 12 , and another of the first branch waveguides 112 is connected to another of the curved waveguide structures 12 .

[0017] Preferably, the adjacent straight waveguides 121 are connected end to end through the curved waveguide 122 to connect all the straight waveguides 121 in the same curved waveguide structure 12 in series, specifically including:

[0018] Each of the curved waveguide structures 12 includes a plurality of straight waveguides 121. According to the distance between the straight waveguides 121 and the first Y-shaped waveguide structure 11, each of the curved waveguide structures 12 specifically includes the first straight waveguide 121 to the jth straight waveguide 121, wherein j>1 and j is an odd number.

[0019] For the first straight waveguide 121, a first end of the first straight waveguide 121 is connected to the first Y-type waveguide structure 11, and a second end of the first straight waveguide 121 is connected to the second straight waveguide 121 through a curved waveguide 122;

[0020] For the j-th straight waveguide 121, the first end of the j-th straight waveguide 121 is connected to the j-1-th straight waveguide 121 through the curved waveguide 122, and the second end of the j-th straight waveguide 121 is used to output the optical signal;

[0021] For the straight waveguides 121 other than the first straight waveguide 121 and the jth straight waveguide 121 , two ends of the straight waveguide 121 are connected to two adjacent straight waveguides 121 through curved waveguides 122 .

[0022] Preferably, all the signal electrodes 21 are divided into two parts on both sides of the first Y-type waveguide structure 11, and the multiple signal electrodes 21 in each part are specifically the first signal electrode 21 to the jth signal electrode 21 according to the distance relative to the first Y-type waveguide structure 11, wherein j>1 and j is an odd number;

[0023] For the first signal electrode 21, the first end of the first signal electrode 21 is used to receive an electrical signal, and the second end of the first signal electrode 21 is connected to the second signal electrode 21;

[0024] For the j-th signal electrode 21, the first end of the j-th signal electrode 21 is connected to the j-1-th signal electrode 21, and the second end of the j-th signal electrode 21 is used to output an electrical signal;

[0025] For the signal electrodes 21 other than the first signal electrode 21 and the j-th signal electrode 21 , both ends of the signal electrode 21 are connected to two adjacent signal electrodes 21 through bent electrodes.

[0026] Preferably, all the ground electrodes 22 are divided into two parts on both sides of the first Y-type waveguide structure 11, and the multiple ground electrodes 22 in each part are specifically the first ground electrode 22 to the jth ground electrode 22 according to the distance relative to the first Y-type waveguide structure 11, wherein j>1 and j is an odd number;

[0027] Adjacent ground electrodes 22 are connected to each other via connectors 6 ; and, for a ground electrode 22 connected with two of the connectors 6 , the two connectors 6 are distributed at two ends of the corresponding ground electrode 22 .

[0028] Preferably, the lithium niobate layer 1 further includes a second Y-type waveguide structure 13, the second Y-type waveguide structure 13 and the first Y-type waveguide structure 11 are arranged opposite to each other, and the second Y-type waveguide structure 13 includes a second trunk waveguide 131 and two second branch waveguides 132, wherein:

[0029] The second trunk waveguide 131 and the two second branch waveguides 132 are respectively connected;

[0030] One of the second branch waveguides 132 is connected to one of the outermost straight waveguides 121 , and another of the second branch waveguides 132 is connected to another outermost straight waveguide 121 .

[0031] Preferably, all the signal electrodes 21 are specifically the 1st signal electrode 21 to the 2j-1th signal electrode 21, wherein j>1, and j is an odd number;

[0032] For the first signal electrode 21, the second end of the first signal electrode 21 is used for inputting an electrical signal, and the first end of the first signal electrode 21 is connected to the second signal electrode 21;

[0033] For the 2j-1th signal electrode 21, the first end of the 2j-1th signal electrode 21 is used for emitting an electrical signal, and the second end of the 2j-1th signal electrode 21 is connected to the 2j-2th signal electrode 21;

[0034] For the signal electrodes 21 other than the first signal electrode 21 and the 2j-1th signal electrode 21 , both ends of the signal electrode 21 are connected to two adjacent signal electrodes 21 through bent electrodes, respectively.

[0035] Preferably, all the ground electrodes 22 are specifically the 1st ground electrode 22 to the 2jth ground electrode 22, wherein j>1 and j is an odd number;

[0036] For the first ground electrode 22, the first end of the first ground electrode 22 is connected to the second ground electrode 22 via a connector 6;

[0037] For the 2jth ground electrode 22, the first end of the 2jth ground electrode 22 is connected to the 2j-1th ground electrode 22 via the connector 6;

[0038] For the ground electrodes 22 other than the first ground electrode 22 and the 2jth ground electrode 22 , both ends of the ground electrode 22 are connected to two adjacent connectors 6 through the connectors 6 , respectively.

[0039] In a second aspect, a method for manufacturing a Y-type thin-film lithium niobate electro-optic modulator is provided, which is applied to the Y-type thin-film lithium niobate electro-optic modulator, comprising:

[0040] The lithium niobate layer 1 is grown on the oxide layer 3, and the lithium niobate layer 1 is etched into a first Y-type waveguide structure 11 and two curved waveguide structures 12, wherein the two curved waveguide structures 12 are symmetrically arranged at two sides of the first Y-type waveguide structure 11 and connected to the first Y-type waveguide structure 11; the curved waveguide structure 12 comprises a plurality of straight waveguides 121 and a plurality of curved waveguides 122, wherein the plurality of straight waveguides 121 are arranged in parallel with each other, and adjacent straight waveguides 121 are connected end to end through the curved waveguides 122, so that all straight waveguides 121 in the same curved waveguide structure 12 are connected in series;

[0041] An electrode 2 is arranged on the lithium niobate layer 1, and the electrode 2 includes a signal electrode 21 and a ground electrode 22. The ground electrode 22 and the signal electrode 21 are respectively arranged on both sides of each straight waveguide 121. The signal electrode 21 and the ground electrode 22 are respectively arranged in parallel with the straight waveguide 121, so as to ensure that the direction of the electric field generated by the ground electrode 22 and the signal electrode 21 is perpendicular to the straight waveguide 121.

[0042] The present invention provides a Y-type thin-film lithium niobate electro-optic modulator and a manufacturing method thereof. The lithium niobate layer on the electro-optic modulator chip is etched into a corresponding curved waveguide structure, and two curved waveguide structures are symmetrically arranged on both sides of the Y-type waveguide structure, thereby ensuring that the heights of the two optical paths are consistent. The curved waveguide structure reduces the space required for the waveguide while ensuring the length of the waveguide. For waveguides of the same length, a chip with a smaller length can be used for mounting. At the same time, signal electrodes and ground electrodes are arranged on both sides of each section of a straight waveguide in the curved waveguide structure, so that the optical signal in the waveguide is modulated to meet the modulation requirements of the electro-optic modulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 It is a partial structural top view of a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0045] Figure 2 is a top view of a lithium niobate layer of a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0046] Figure 3 is a top view of a lithium niobate layer of another Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0047] Figure 4 is a partial structural top view of another Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0048] Figure 5 It is a partial structural top view of a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0049] Figure 6 is a cross-sectional view of a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0050] Figure 7is a top view of a lithium niobate layer of a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0051] Figure 8 is a top view of a lithium niobate layer of another Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0052] Fig. 9 is a partial structural top view of another Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0053] Fig.10 It is a partial structural top view of a Y-type thin-film lithium niobate electro-optic modulator with an optical transmission path provided by an embodiment of the present invention;

[0054] Fig.11 is a partial structural top view of another Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0055] Fig.12 is a cross-sectional view of another Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0056] Fig.13 is a cross-sectional view of another Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0057] Fig.14 It is a partial structural top view of a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0058] Fig.15 It is a partial structural top view of a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0059] Fig.16 It is a partial structural top view of a Y-type thin-film lithium niobate electro-optic modulator with a light transmission path provided by an embodiment of the present invention;

[0060] Fig.17 It is a partial structural top view of another Y-type thin-film lithium niobate electro-optic modulator with a light transmission path provided by an embodiment of the present invention;

[0061] Fig.18 It is a method flow chart of a method for manufacturing a Y-type thin-film lithium niobate electro-optic modulator provided by an embodiment of the present invention;

[0062] Wherein, the accompanying drawings are marked as follows:

[0063] Lithium niobate layer 1; first Y-type waveguide 11; first trunk waveguide 111; first branch waveguide 112; curved waveguide structure 12; straight waveguide 121; curved waveguide 122; second Y-type waveguide structure 13; second trunk waveguide 131; second branch waveguide 132; electrode 2; signal electrode 21; ground electrode 22; oxide layer 3; substrate 4; buffer layer 5; connector 6. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0065] In the description of the present invention, the terms "inside", "outside", "longitudinal", "lateral", "upper", "lower", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0066] The terms "first", "second", etc. in the present invention are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0067] In this application, unless otherwise specified or limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. In addition, the term "coupling" can be a way of achieving electrical connection for signal transmission.

[0068] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0069] Embodiment 1:

[0070] Embodiment 1 of the present invention provides a Y-type thin film lithium niobate electro-optic modulator, such as Figure 1 As shown, it includes: a lithium niobate layer 1, an electrode 2 and an oxide layer 3, wherein:

[0071] The lithium niobate layer 1 is arranged on the oxide layer 3 ; the lithium niobate layer 1 includes a first Y-type waveguide structure 11 and two curved waveguide structures 12 , and the two curved waveguide structures 12 are symmetrically arranged on both sides of the first Y-type waveguide structure 11 and connected to the first Y-type waveguide structure 11 .

[0072] In this embodiment, a corresponding lithium niobate layer 1 is first grown on the oxide layer 3, and then the lithium niobate layer 1 is etched into a ridge waveguide to obtain a corresponding first Y-type waveguide structure 11 and two curved waveguide structures 12, such as Figure 2 As shown, the first Y-type waveguide structure 11 is a Y-shaped waveguide structure on the left, and the curved waveguide structure 12 is symmetrically arranged on both sides of the first Y-type waveguide structure 11 and connected to the first Y-type waveguide structure 11; in this embodiment, the first Y-type waveguide structure 11 is used to input an optical signal, and transmits the optical signal to the two curved waveguide structures 12 respectively through the first Y-type waveguide structure 11, and the optical signal is transmitted toward the outside through the two curved waveguide structures 12, thereby ensuring the high consistency of the two optical paths, and is suitable for application scenarios such as integrated optical gyroscopes that require high consistency of the two optical paths.

[0073] like Figure 3 As shown, the curved waveguide structure 12 includes a plurality of straight waveguides 121 and a plurality of curved waveguides 122. The plurality of straight waveguides 121 are arranged in parallel with each other, and adjacent straight waveguides 121 are connected end to end through the curved waveguides 122, so that all straight waveguides 121 in the same curved waveguide structure 12 are connected in series.

[0074] In this embodiment, the straight waveguide 121 is a straight waveguide portion, and the curved waveguide 122 is a curved waveguide portion. A plurality of straight waveguides 121 are arranged in a parallel array, and adjacent straight waveguides 121 are connected by the curved waveguides 122. While ensuring the length of the entire waveguide, the size of the space occupied by the waveguide is reduced, thereby avoiding the need to increase the chip length.

[0075] like Figure 4 As shown, the electrode 2 is located on the lithium niobate layer 1, and the electrode 2 includes a signal electrode 21 and a ground electrode 22. The ground electrode 22 and the signal electrode 21 are respectively arranged on both sides of each straight waveguide 121, and the signal electrode 21 and the ground electrode 22 are respectively arranged in parallel with the straight waveguide 121, so as to ensure that the direction of the electric field generated by the ground electrode 22 and the signal electrode 21 is perpendicular to the straight waveguide 121.

[0076] The electrode 2 is grown on the etched lithium niobate layer 1 and the oxide layer 3, and is etched accordingly to obtain a signal electrode 21 and a ground electrode 22. In this embodiment, a strip-shaped signal electrode 21 and a strip-shaped ground electrode 22 are correspondingly provided on both sides of each straight waveguide 121. At the same time, the signal electrode 21 and the ground electrode 22 are parallel to the straight waveguide 121. The signal electrodes 21 and the ground electrodes 22 on both sides of a straight waveguide 121 form an electric field correspondingly. Figure 1 and Figure 4 The direction of the electric field is the direction of the black arrow, and the direction of the electric field is perpendicular to the signal electrode 21 and the ground electrode 22, and therefore also perpendicular to the straight waveguide 121, thereby modulating the optical signal in the waveguide to ensure that the direction of the electric field is consistent with the direction of the optical axis in the waveguide, thereby achieving the modulation requirements of the electro-optical modulator.

[0077] like Figure 5 As shown, the large white arrow is the transmission direction of the optical signal in the waveguide, and the black arrow is the direction of the electric field.

[0078] It is worth mentioning that in this embodiment, the straight waveguide 121 occupies the majority of the curved waveguide structure 12, while the curved waveguide 122 occupies a small portion. Therefore, in this embodiment, only the influence of the straight waveguide 121 needs to be considered for the propagation of the optical signal and the electro-optical modulation, and the influence of the curved waveguide 122 can be ignored.

[0079] In this embodiment, the lithium niobate layer 1 on the electro-optic modulator chip is etched into a corresponding curved waveguide structure 12, and two curved waveguide structures 12 are symmetrically arranged on both sides of the optical signal entrance and exit, ensuring the high consistency of the two optical paths. The curved waveguide structure 12 reduces the space required for the waveguide while ensuring the waveguide length, and realizes the function that the waveguide of the same length can be carried by a chip with a smaller length. At the same time, the signal electrode 21 and the ground electrode 22 are arranged on both sides of each straight waveguide 121 in the curved waveguide structure 12 to ensure that the direction of the electric field is consistent with the direction of the optical axis, thereby realizing the modulation requirements of the electro-optic modulator.

[0080] In this embodiment, the Y-type thin-film lithium niobate electro-optic modulator provided requires other basic parts and layers in addition to the lithium niobate layer 1, the electrode 2 and the oxide layer 3 to realize the basic functions of the electro-optic modulator. Therefore, this embodiment also involves the following designs:

[0081] like Figure 6 As shown, the Y-type thin film lithium niobate electro-optic modulator further includes: a substrate 4 and a buffer layer 5, wherein:

[0082] The substrate 4 is located below the oxide layer 3 ; the buffer layer 5 is disposed between the lithium niobate layer 1 and the electrode 2 .

[0083] In this embodiment, the substrate 4 may be a thin film lithium niobate wafer substrate, and the material may be silicon, lithium niobate or quartz.

[0084] The material of the oxide layer 3 can be silicon dioxide or benzocyclobutene, and the thickness of the oxide layer 3 can be 0.5um to 20um.

[0085] The material of the lithium niobate layer 1 can be an X-cut lithium niobate thin film material, the waveguide thickness can be 600nm, and when the lithium niobate layer 1 is etched accordingly, the etching depth can be 300nm; it should be noted that, in this embodiment, in addition to lithium niobate material, the lithium niobate layer 1 can also be made of silicon, silicon nitride or lithium tantalate and other materials.

[0086] The buffer pool material may be silicon dioxide or total benzocyclobutene, and the buffer pool thickness may be 0.1um-1um.

[0087] The material of the electrode 2 can be gold, copper or tungsten, and is not limited to single metal.

[0088] In this embodiment, the first Y-type waveguide structure 11 serves as an input port for inputting optical signals, and the optical signals need to be transmitted to the two curved waveguide structures 12 on both sides, so that the optical signals are transmitted in the entire waveguide structure. Therefore, this embodiment also involves the following designs:

[0089] like Figure 7 As shown, the first Y-type waveguide structure 11 includes a first trunk waveguide 111 and two first branch waveguides 112, wherein:

[0090] The first trunk waveguide 111 and the two first branch waveguides 112 are connected respectively; one of the first branch waveguides 112 is connected to one of the curved waveguide structures 12 , and the other first branch waveguide 112 is connected to the other curved waveguide structure 12 .

[0091] In this embodiment, the first trunk waveguide 111 is used as an input port for optical signals, and the two first branch waveguides 112 are connected to the first trunk waveguide 111. The input optical signal is simultaneously transmitted to the curved waveguide structures 12 on both sides through the two first branch waveguides 112, thereby achieving simultaneous transmission of two optical paths and highly consistent optical paths. After the optical signals are respectively transmitted to the curved waveguide structures 12 on both sides of the first Y-shaped waveguide structure 11, they are output from the outermost straight waveguides 121 of the two curved waveguide structures 12.

[0092] In addition, the first Y-type waveguide structure 11 can also serve as an output port for optical signal transmission, that is, the optical signal is input from the outermost straight waveguide 121 of the two curved waveguide structures 12, and after being transmitted in the curved waveguide structure 12, is respectively input from the two first branch waveguides 112 and output from the first trunk waveguide 111.

[0093] In this embodiment, in order to reduce the space occupied by the waveguide while ensuring the length of the waveguide, thereby further reducing the size of the chip, the bending distribution of the waveguide is specifically as follows:

[0094] like Figure 8 As shown, the adjacent straight waveguides 121 are connected end to end through the curved waveguide 122 to connect all the straight waveguides 121 in the same curved waveguide structure 12 in series, specifically including:

[0095] Each of the curved waveguide structures 12 includes a plurality of straight waveguides 121. According to the distance of the straight waveguides 121 relative to the first Y-shaped waveguide structure 11, from small to large, each of the curved waveguide structures 12 specifically includes the first straight waveguide 121 to the jth straight waveguide 121, wherein j>1 and j is an odd number;

[0096] like Figure 8 As shown, in this embodiment, since the arrangement and connection methods of the straight waveguides 121 on both sides of the first Y-type waveguide structure 11 are symmetrical to each other, only the straight waveguide 121 on one side of the first Y-type waveguide structure 11 is described in this embodiment, and the straight waveguide 121 on the other side can refer to the description of this side; in this embodiment, the distances of the first straight waveguide 121 to the jth straight waveguide 121 relative to the first Y-type waveguide structure 11 gradually increase; it should be noted that, Figure 8 Only three straight waveguides 121 are drawn on one side of the first Y-type waveguide structure 11, which is only used as an implementable example and does not limit the number of straight waveguides 121 in other scenarios.

[0097] It should be noted that, since the two straight waveguides 121 located on the outermost sides of the two curved waveguide structures 12 need to be used for outputting optical signals, the two straight waveguides 121 on the outermost sides can only be oriented toward the opposite end of the first Y-shaped waveguide structure 11, that is, Figure 8 As can be seen from the right end of the figure, if the sequence number of the outermost straight waveguide 121 is an even number, the straight waveguide 121 will be oriented toward Figure 8 The left end of the curved waveguide structure 12 does not meet the requirements. Therefore, the sequence number of the outermost straight waveguide 121 should be an odd number other than 1, so the number of straight waveguides 121 in the curved waveguide structure 12 should be an odd number. Figure 8 As shown, a connection arrangement method for this scenario is provided.

[0098] like Figure 8 As shown, for the first straight waveguide 121 , the first end of the first straight waveguide 121 is connected to the first Y-type waveguide structure 11 , and the second end of the first straight waveguide 121 is connected to the second straight waveguide 121 through the curved waveguide 122 .

[0099] like Figure 8 As shown, for the j-th straight waveguide 121, the first end of the j-th straight waveguide 121 is connected to the j-1-th straight waveguide 121 through the curved waveguide 122; the second end of the j-th straight waveguide 121 is used for outputting optical signals.

[0100] For the straight waveguides 121 other than the first straight waveguide 121 and the jth straight waveguide 121, both ends of the straight waveguide 121 are connected to two adjacent straight waveguides 121 through curved waveguides 122. The above connection method is specifically as follows:

[0101] For the i-th straight waveguide 121, where i is a positive integer, 1<i<j, i gradually increases according to the distance of the straight waveguide 121 relative to the first Y-type waveguide structure 11, specifically including:

[0102] like Figure 8 As shown, when i is an odd number, the first end of the i-th straight waveguide 121 is connected to the i-1-th straight waveguide 121 through the curved waveguide 122 , and the second end of the i-th straight waveguide 121 is connected to the i+1-th straight waveguide 121 through the curved waveguide 122 .

[0103] like Figure 8 As shown, when i is an even number, the first end of the i-th straight waveguide 121 is connected to the i+1-th straight waveguide 121 through the curved waveguide 122 , and the second end of the i-th straight waveguide 121 is connected to the i-1-th straight waveguide 121 through the curved waveguide 122 .

[0104] like Figure 8 As shown, in this embodiment, the first end faces a side position where the first Y-type waveguide structure 11 is located, and the second end faces a relative position of the first Y-type waveguide structure 11 .

[0105] Through the above connection method, the two curved waveguide structures 12 are bent and arranged, and the corresponding optical signal transmission is realized, such as Fig.10 As shown, the large white arrow is the transmission path of the optical signal in the curved waveguide structure 12 when the optical signal is input from the first Y-type waveguide structure 11 .

[0106] Furthermore, in order to achieve high-bandwidth modulation performance, the signal electrode 21 and the ground electrode 22 need to be distributed and arranged accordingly in this embodiment to ensure that the transmission direction of the electrical signal in the signal electrode 21 is consistent with the transmission direction of the optical signal, so that the microwave phase velocity is consistent with the optical wave group velocity, thereby achieving high-bandwidth modulation performance. Therefore, this embodiment also provides a preferred solution:

[0107] The lithium niobate layer 1 is arranged on the oxide layer 3; the lithium niobate layer 1 includes a first Y-type waveguide structure 11 and two curved waveguide structures 12, the two curved waveguide structures 12 are symmetrically arranged on both sides of the first Y-type waveguide structure 11 and connected to the first Y-type waveguide structure 11; the curved waveguide structure 12 includes a plurality of straight waveguides 121 and a plurality of curved waveguides 122, the plurality of straight waveguides 121 are arranged in parallel with each other, and adjacent straight waveguides 121 are connected end to end through the curved waveguide 122, so as to connect all the straight waveguides 121 in the same curved waveguide structure 12 in series; the signal electrode 21 is located on the lithium niobate layer 1, and the signal electrode 21 is arranged on one side of each straight waveguide 121, and the path direction of all the signal electrodes 21 is consistent with the direction path of the curved waveguide structure 12, so as to ensure that the flow direction of the electrical signal in the signal electrode 21 is consistent with the flow direction of the optical signal in the curved waveguide structure 12.

[0108] like Fig. 9 As shown, all the signal electrodes 21 are divided into two parts on both sides of the first Y-type waveguide structure 11, and the multiple signal electrodes 21 in each part are arranged from small to large according to the distance relative to the first Y-type waveguide structure 11. The multiple signal electrodes 21 in each part are specifically the first signal electrode 21 to the jth signal electrode 21, wherein j>1 and j is an odd number. Wherein, j is equal to the number of straight waveguides 121 included in the curved waveguide structure 12.

[0109] In this embodiment, since a signal electrode 21 and a ground electrode 22 are correspondingly arranged on both sides of each straight waveguide 121 in the two curved waveguide structures 12, all the signal electrodes 21 are also symmetrically distributed on both sides of the first Y-type waveguide structure 11, which is consistent with the arrangement of the straight waveguides 121; therefore, in this embodiment, only the signal electrode 21 on any one side of the first Y-type waveguide structure 11 is described, and the signal electrode 21 on the other side can refer to the description of that side; in this embodiment, the distances of the 1st signal electrode 21 to the jth signal electrode 21 relative to the first Y-type waveguide structure 11 gradually increase. It should be noted that Fig. 9 Only three signal electrodes 21 are drawn on one side of the first Y-type waveguide structure 11, which is only used as an implementable example and does not limit the number of the signal electrodes 21 in other scenarios.

[0110] It should be noted that in this embodiment, the single signal electrode 21 refers to Fig. 9 The signal electrodes 21 are strip-shaped portions, and the electrode portions that are bent and used for connection do not affect the electro-optical modulation. Therefore, in this embodiment, the separate signal electrodes 21 only refer to the strip-shaped signal electrodes 21.

[0111] like Fig. 9 As shown, for the first signal electrode 21 , the first end of the first signal electrode 21 is used to receive an electrical signal, and the second end of the first signal electrode 21 is connected to the second signal electrode 21 .

[0112] For the j-th signal electrode 21 , the first end of the j-th signal electrode 21 is connected to the j−1-th signal electrode 21 ; and the second end of the j-th signal electrode 21 is used for outputting an electrical signal.

[0113] For the signal electrodes 21 other than the first signal electrode 21 and the jth signal electrode 21, both ends of the signal electrode 21 are connected to two adjacent signal electrodes 21 through curved electrodes. The above connection method is specifically as follows:

[0114] For the i-th signal electrode 21, where i is a positive integer, 1<i<j, i gradually increases according to the distance between the signal electrode 21 and the first Y-type waveguide structure 11, specifically including:

[0115] When i is an odd number, the first end of the i-th signal electrode 21 is connected to the i-1-th signal electrode 21 , and the second end of the i-th signal electrode 21 is connected to the i+1-th signal electrode 21 .

[0116] When i is an even number, the first end of the i-th signal electrode 21 is connected to the i+1-th signal electrode 21 , and the second end of the i-th signal electrode 21 is connected to the i-1-th signal electrode 21 .

[0117] like Fig. 9 As shown, it should be noted that when different signal electrodes 21 are connected, they can be connected in a curved manner or in a vertical corner manner; the signal electrodes 21 are arranged and arranged in the above manner, and the electrical signal is incident from the first end of the first signal electrode 21, such as Fig.10 As shown, Fig.10 The black long arrow in the figure is the transmission path of the electric signal in the signal electrode 21, and the electric signal is finally output from the two outermost signal electrodes 21. This ensures that the propagation directions of the optical signal and the radio frequency signal (ie, the electric signal) are consistent.

[0118] In this embodiment, the ground electrode 22 also needs to be arranged and configured accordingly with the signal electrode 21 to generate a corresponding electric field. Therefore, this embodiment also involves the following designs:

[0119] like Fig.11 As shown, all the ground electrodes 22 are divided into two parts on both sides of the first Y-type waveguide structure 11, and the multiple ground electrodes 22 in each part are arranged from small to large according to the distance relative to the first Y-type waveguide structure 11. The multiple ground electrodes 22 in each part are specifically the 1st ground electrode 22 to the jth ground electrode 22, where j>1 and j is an odd number.

[0120] In this embodiment, since a signal electrode 21 and a ground electrode 22 are correspondingly arranged on both sides of each straight waveguide 121 in the two curved waveguide structures 12, all the ground electrodes 22 are symmetrically distributed on both sides of the first Y-type waveguide structure 11, which is consistent with the arrangement of the straight waveguides 121; therefore, in this embodiment, only the ground electrode 22 on one side of the first Y-type waveguide structure 11 is described, and the ground electrode 22 on the other side can refer to the description of this side; in this embodiment, the distances of the first ground electrode 22 to the jth ground electrode 22 relative to the first Y-type waveguide structure 11 gradually increase; it should be noted that, Fig.11 Only three ground electrodes 22 are drawn on one side of the first Y-type waveguide structure 11, which is only used as an implementable example and does not limit the number of ground electrodes 22 in other scenarios.

[0121] Adjacent ground electrodes 22 are connected via connectors 6; and for a ground electrode 22 connected with two of the connectors 6, the two connectors 6 are distributed at both ends of the corresponding ground electrode 22. The above connection method is specifically as follows:

[0122] like Fig.11 As shown, for the first ground electrode 22 , the second end of the first ground electrode 22 is connected to the second ground electrode 22 via the connector 6 .

[0123] For the j-th ground electrode 22 , the first end of the j-th ground electrode 22 is connected to the j−1-th ground electrode 22 via the connector 6 .

[0124] For the i-th ground electrode 22, where i is a positive integer, 1<i<j, i gradually increases according to the distance between the ground electrode 22 and the first Y-type waveguide structure 11, specifically including:

[0125] When i is an odd number, the first end of the i-th ground electrode 22 is connected to the i-1-th ground electrode 22 through the connector 6 , and the second end of the i-th ground electrode 22 is connected to the i+1-th ground electrode 22 through the connector 6 .

[0126] When i is an even number, the first end of the i-th ground electrode 22 is connected to the i+1-th ground electrode 22 through the connector 6 , and the second end of the i-th ground electrode 22 is connected to the i-1-th ground electrode 22 through the connector 6 .

[0127] like Figure 11-13 As shown, it should be noted that, in this embodiment, each ground electrode 22 is in a strip shape, and the connector 6 can be connected by gold wire bonding, metal bridge connection, or flip-chip welding transfer. Fig.12 and Fig.13 As shown, the connector 6 is connected from above the signal electrode 21 to avoid short circuit between the signal electrode 21 and the ground electrode 22 .

[0128] Embodiment 2:

[0129] Embodiment 2 of the present invention provides another Y-type thin film lithium niobate electro-optic modulator based on Embodiment 1, mainly by using the electro-optic modulator as a Mach-Zehnder interferometer modulation structure, that is, based on Embodiment 1, a waveguide structure is arranged at the opposite side of the first Y-type waveguide structure 11, and an optical signal is input through the waveguide structure, while the original first Y-type waveguide structure 11 is used for optical signal output, and the structure is as follows:

[0130] like Fig.14 and Fig.15 As shown, the lithium niobate layer 1 further includes a second Y-type waveguide structure 13, the second Y-type waveguide structure 13 and the first Y-type waveguide structure 11 are arranged opposite to each other, and the second Y-type waveguide structure 13 includes a second trunk waveguide 131 and two second branch waveguides 132, wherein:

[0131] The second trunk waveguide 131 is connected to two of the second branch waveguides 132 respectively; one of the second branch waveguides 132 is connected to one of the outermost straight waveguides 121 , and the other second branch waveguide 132 is connected to the other outermost straight waveguide 121 .

[0132] like Fig.14 and Fig.15 As shown, in this embodiment, the optical signal can be input through the second Y-type waveguide structure 13. After passing through the two curved waveguide structures 12, the optical signal flows to the first Y-type waveguide structure 11 and is output through the first Y-type waveguide structure 11.

[0133] Compared with Example 1, in this embodiment, due to the change in the flow direction of the optical signal, the signal electrode 21 and the ground electrode 22 need to be re-arranged and designed. After ensuring that the signal electrode 21 and the ground electrode 22 are respectively arranged in parallel on both sides of each straight waveguide 121, different signal electrodes 21 need to be connected to each other, and the propagation directions of the electrical signal in the signal electrode 21 and the optical signal in the waveguide are consistent. Therefore, this embodiment also involves the following designs:

[0134] like Fig.16 As shown, all the signal electrodes 21 are specifically the 1st signal electrode 21 to the 2j-1th signal electrode 21, wherein j>1 and j is an odd number.

[0135] In this embodiment, since the optical signal is transmitted from the waveguides on both sides to the middle waveguide, in this embodiment, all signal electrodes 21 are connected in series, and it is necessary to ensure that the transmission direction of the electrical signal is consistent with the transmission direction of the optical signal to achieve high bandwidth modulation performance. Fig.16 As shown, in this embodiment, j is the number of straight waveguides 121 on either side of the first Y-type waveguide structure 11 in Example 1. Since all signal electrodes 21 in this embodiment are connected in series, in order to ensure the consistency of the electrical signal transmission direction and the optical signal transmission direction, the number of signal electrodes 21 in this embodiment is 2j-1, and the 1st signal electrode 21 to the 2j-1th signal electrode 21 are the arrangement order of all signal electrodes 21.

[0136] like Fig.16 As shown, for the first signal electrode 21 , the second end of the first signal electrode 21 is used for inputting an electrical signal, and the first end of the first signal electrode 21 is connected to the second signal electrode 21 .

[0137] For the 2j-1th signal electrode 21 , the first end of the 2j-1th signal electrode 21 is used for emitting an electrical signal, and the second end of the 2j-1th signal electrode 21 is connected to the 2j-2th signal electrode 21 .

[0138] For the signal electrodes 21 other than the first signal electrode 21 and the 2j-1th signal electrode 21, both ends of the signal electrode 21 are connected to two adjacent signal electrodes 21 through curved electrodes. The above connection method is specifically as follows:

[0139] For the h-th signal electrode 21, where h is a positive integer, 1<h<2j-1, and h increases gradually according to the arrangement sequence of all the signal electrodes 21, specifically including:

[0140] When h is an odd number, the first end of the hth signal electrode 21 is connected to the h+1th signal electrode 21 , and the second end of the hth signal electrode 21 is connected to the h−1th signal electrode 21 .

[0141] When h is an even number, the first end of the hth signal electrode 21 is connected to the h−1th signal electrode 21 , and the second end of the hth signal electrode 21 is connected to the h+1th signal electrode 21 .

[0142] like Fig.16 As shown, by arranging the signal electrodes 21 in the above manner, it can be ensured that the transmission direction of the optical signal in each straight waveguide 121 is consistent with the transmission direction of the electrical signal in its corresponding signal electrode 21. Fig.16 The electrical signal is input from the second end of the uppermost signal electrode 21. The direction of the thick black arrow in the figure is the transmission direction of the electrical signal. The electrical signal is finally output from the first end of the lowermost signal electrode 21 in the figure. Fig.16 It can be seen that the transmission direction of the electrical signal in the signal electrode 21 is consistent with the transmission direction of the optical signal in the waveguide at the corresponding position, thereby achieving high-bandwidth modulation performance under the Mach-Zehnder interferometer modulation structure.

[0143] In this embodiment, the ground electrode 22 also needs to be arranged in the same manner as the signal electrode 21, so this embodiment also involves the following designs:

[0144] like Fig.17 As shown, all the ground electrodes 22 specifically include the 1st ground electrode 22 to the 2jth ground electrode 22, wherein j>1 and j is an odd number.

[0145] In this embodiment, in order to ensure the consistency of the transmission direction of the electrical signal and the transmission direction of the optical signal, the number of the ground electrodes 22 is 2j, and the first ground electrode 22 to the 2jth ground electrode 22 are the arrangement order of all the ground electrodes 22.

[0146] like Fig.17 As shown, for the first ground electrode 22 , the first end of the first ground electrode 22 is connected to the second ground electrode 22 via a connector 6 .

[0147] For the 2j-th ground electrode 22 , the first end of the 2j-th ground electrode 22 and the 2j−1-th ground electrode 22 are connected via the connector 6 .

[0148] For the ground electrodes 22 other than the first ground electrode 22 and the 2jth ground electrode 22, both ends of the ground electrode 22 are connected to two adjacent connectors 6 through the connectors 6. The above connection method is specifically as follows:

[0149] For the kth ground electrode 22, where k is a positive integer, 1<k<2j, and k increases gradually according to the arrangement sequence of all the ground electrodes 22, specifically including:

[0150] When k is an odd number, the first end of the kth ground electrode 22 is connected to the k+1th ground electrode 22 through the connector 6 , and the second end of the kth ground electrode 22 is connected to the k−1th ground electrode 22 through the connector 6 .

[0151] When k is an even number, the first end of the kth ground electrode 22 is connected to the k−1th ground electrode 22 through the connector 6 , and the second end of the kth ground electrode 22 is connected to the k+1th ground electrode 22 through the connector 6 .

[0152] like Fig.17 As shown, in this embodiment, each ground electrode 22 is in a strip shape, and the connector 6 can be connected by gold wire bonding, metal bridge connection or flip chip welding. Fig.12 and Fig.13 As shown, the connector 6 is connected from above the signal electrode 21 to avoid short circuit between the signal electrode 21 and the ground electrode 22 .

[0153] Embodiment 3:

[0154] Embodiment 3 of the present invention provides a method for manufacturing a Y-type thin-film lithium niobate electro-optic modulator based on Embodiment 1 and Embodiment 2, which is applied to the Y-type thin-film lithium niobate electro-optic modulator in Embodiment 1 and Embodiment 2. Fig.18 As shown, the method flow includes:

[0155] In step 101 , the lithium niobate layer 1 is grown on the oxide layer 3 , and the lithium niobate layer 1 is etched into a first Y-type waveguide structure 11 and two bent waveguide structures 12 .

[0156] The two curved waveguide structures 12 are symmetrically arranged at both sides of the first Y-type waveguide structure 11 and connected to the first Y-type waveguide structure 11; the curved waveguide structure 12 includes a plurality of straight waveguides 121 and a plurality of curved waveguides 122, the plurality of straight waveguides 121 are arranged parallel to each other, and adjacent straight waveguides 121 are connected end to end through the curved waveguides 122, so as to connect all the straight waveguides 121 in the same curved waveguide structure 12 in series.

[0157] In step 102, an electrode 2 is arranged on the lithium niobate layer 1, and the electrode 2 includes a signal electrode 21 and a ground electrode 22. The ground electrode 22 and the signal electrode 21 are respectively arranged on both sides of each straight waveguide 121, and the signal electrode 21 and the ground electrode 22 are respectively arranged in parallel with the straight waveguide 121, so as to ensure that the direction of the electric field generated by the ground electrode 22 and the signal electrode 21 is perpendicular to the straight waveguide 121.

[0158] Regarding the specific structure of the Y-type thin film lithium niobate electro-optic modulator, please refer to the aforementioned embodiment and will not be described in detail here.

[0159] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A Y-type thin film lithium niobate electro-optic modulator, characterized in that: include: A lithium niobate layer (1), an electrode (2) and an oxide layer (3), wherein: The lithium niobate layer (1) is disposed on the oxide layer (3); The lithium niobate layer (1) comprises a first Y-type waveguide structure (11) and two curved waveguide structures (12), wherein the two curved waveguide structures (12) are symmetrically arranged on both sides of the first Y-type waveguide structure (11) and connected to the first Y-type waveguide structure (11); The curved waveguide structure (12) comprises a plurality of straight waveguides (121) and a plurality of curved waveguides (122); the plurality of straight waveguides (121) are arranged in parallel with each other, and adjacent straight waveguides (121) are connected end to end via the curved waveguides (122), so that all straight waveguides (121) in the same curved waveguide structure (12) are connected in series; The electrode (2) is located on the lithium niobate layer (1), and the electrode (2) comprises a signal electrode (21) and a ground electrode (22). The ground electrode (22) and the signal electrode (21) are respectively arranged on both sides of each straight waveguide (121), and the signal electrode (21) and the ground electrode (22) are respectively arranged in parallel with the straight waveguide (121), so as to ensure that the direction of the electric field generated by the ground electrode (22) and the signal electrode (21) is perpendicular to the straight waveguide (121).

2. The Y-type thin film lithium niobate electro-optic modulator according to claim 1, characterized in that: The Y-type thin-film lithium niobate electro-optic modulator further comprises: a substrate (4) and a buffer layer (5), wherein: The substrate (4) is located below the oxide layer (3); The buffer layer (5) is arranged between the lithium niobate layer (1) and the electrode (2).

3. The Y-type thin film lithium niobate electro-optic modulator according to claim 1, characterized in that: The first Y-type waveguide structure (11) comprises a first trunk waveguide (111) and two first branch waveguides (112), wherein: The first trunk waveguide (111) and the two first branch waveguides (112) are respectively connected; One of the first branch waveguides (112) is connected to one of the curved waveguide structures (12), and another of the first branch waveguides (112) is connected to another of the curved waveguide structures (12).

4. The Y-type thin film lithium niobate electro-optic modulator according to claim 1, characterized in that: The adjacent straight waveguides (121) are connected end to end via the curved waveguide (122) so as to connect all the straight waveguides (121) in the same curved waveguide structure (12) in series, specifically comprising: Each of the curved waveguide structures (12) comprises a plurality of straight waveguides (121), and according to the distance of the straight waveguides (121) relative to the first Y-shaped waveguide structure (11), each of the curved waveguide structures (12) specifically comprises the first straight waveguide (121) to the jth straight waveguide (121), wherein j>1 and j is an odd number; For the first straight waveguide (121), a first end of the first straight waveguide (121) is connected to the first Y-type waveguide structure (11), and a second end of the first straight waveguide (121) is connected to the second straight waveguide (121) via a curved waveguide (122); For the jth straight waveguide (121), the first end of the jth straight waveguide (121) and the j-1th straight waveguide (121) are connected via a curved waveguide (122), and the second end of the jth straight waveguide (121) is used for outputting an optical signal; For the straight waveguides (121) other than the first straight waveguide (121) and the jth straight waveguide (121), two ends of the straight waveguide (121) are respectively connected to two adjacent straight waveguides (121) via curved waveguides (122).

5. The Y-type thin film lithium niobate electro-optic modulator according to claim 1, characterized in that: All the signal electrodes (21) are divided into two parts on both sides of the first Y-type waveguide structure (11), and the multiple signal electrodes (21) in each part are specifically the first signal electrode (21) to the jth signal electrode (21) according to the distance relative to the first Y-type waveguide structure (11), wherein j>1 and j is an odd number; For the first signal electrode (21), the first end of the first signal electrode (21) is used to receive an electrical signal, and the second end of the first signal electrode (21) is connected to the second signal electrode (21); For the j-th signal electrode (21), a first end of the j-th signal electrode (21) is connected to a j-1-th signal electrode (21), and a second end of the j-th signal electrode (21) is used for outputting an electrical signal; For signal electrodes (21) other than the first signal electrode (21) and the jth signal electrode (21), two ends of the signal electrode (21) are connected to two adjacent signal electrodes (21) via bent electrodes.

6. The Y-type thin film lithium niobate electro-optic modulator according to claim 5, characterized in that: All the ground electrodes (22) are divided into two parts on both sides of the first Y-type waveguide structure (11), and the multiple ground electrodes (22) in each part are specifically the first ground electrode (22) to the jth ground electrode (22) according to the distance relative to the first Y-type waveguide structure (11), wherein j>1 and j is an odd number; Adjacent ground electrodes (22) are connected via connectors (6); and for a ground electrode (22) connected with two of the connectors (6), the two connectors (6) are distributed at both ends of the corresponding ground electrode (22).

7. The Y-type thin film lithium niobate electro-optic modulator according to claim 1, characterized in that: The lithium niobate layer (1) further comprises a second Y-type waveguide structure (13), the second Y-type waveguide structure (13) and the first Y-type waveguide structure (11) are arranged opposite to each other, the second Y-type waveguide structure (13) comprises a second trunk waveguide (131) and two second branch waveguides (132), wherein: The second trunk waveguide (131) and the two second branch waveguides (132) are respectively connected; One of the second branch waveguides (132) is connected to one of the outermost straight waveguides (121), and another of the second branch waveguides (132) is connected to another outermost straight waveguide (121).

8. The Y-type thin film lithium niobate electro-optic modulator according to claim 7, characterized in that: All the signal electrodes (21) are specifically the 1st signal electrode (21) to the 2j-1th signal electrode (21), wherein j>1 and j is an odd number; For the first signal electrode (21), the second end of the first signal electrode (21) is used for inputting an electrical signal, and the first end of the first signal electrode (21) is connected to the second signal electrode (21); For the 2j-1th signal electrode (21), the first end of the 2j-1th signal electrode (21) is used for emitting an electrical signal, and the second end of the 2j-1th signal electrode (21) is connected to the 2j-2th signal electrode (21); For signal electrodes (21) other than the first signal electrode (21) and the 2j-1th signal electrode (21), two ends of the signal electrode (21) are connected to two adjacent signal electrodes (21) via bent electrodes.

9. The Y-type thin film lithium niobate electro-optic modulator according to claim 8, characterized in that: All the ground electrodes (22) are specifically the first ground electrode (22) to the 2jth ground electrode (22), wherein j>1 and j is an odd number; For the first ground electrode (22), the first end of the first ground electrode (22) and the second ground electrode (22) are connected via a connector (6); For the 2jth ground electrode (22), the first end of the 2jth ground electrode (22) and the 2j-1th ground electrode (22) are connected via a connector (6); For the ground electrodes (22) other than the first ground electrode (22) and the 2jth ground electrode (22), two ends of the ground electrode (22) are connected to two adjacent connectors (6) via connectors (6) respectively.

10. A method for manufacturing a Y-type thin-film lithium niobate electro-optic modulator, applied to the Y-type thin-film lithium niobate electro-optic modulator as claimed in any one of claims 1 to 9, characterized in that: include: The lithium niobate layer (1) is grown on the oxide layer (3), and the lithium niobate layer (1) is etched into a first Y-type waveguide structure (11) and two curved waveguide structures (12), wherein the two curved waveguide structures (12) are symmetrically arranged at two sides of the first Y-type waveguide structure (11) and connected to the first Y-type waveguide structure (11); the curved waveguide structure (12) comprises a plurality of straight waveguides (121) and a plurality of curved waveguides (122), wherein the plurality of straight waveguides (121) are arranged in parallel with each other, and adjacent straight waveguides (121) are connected end to end via the curved waveguides (122), so that all straight waveguides (121) in the same curved waveguide structure (12) are connected in series; An electrode (2) is arranged on the lithium niobate layer (1), the electrode (2) comprising a signal electrode (21) and a ground electrode (22), the ground electrode (22) and the signal electrode (21) are arranged on both sides of each straight waveguide (121), and the signal electrode (21) and the ground electrode (22) are arranged in parallel with the straight waveguide (121), thereby ensuring that the direction of the electric field generated by the ground electrode (22) and the signal electrode (21) is perpendicular to the straight waveguide (121).

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