A high-speed parallel laser three-dimensional photon wire bonding method and system based on multi-focus control

Abstract

The present invention provides a high-speed parallel laser three-dimensional photon wire bonding method and system based on multi-focus control, which belongs to the technical field of silicon photonic chip production. The method includes the following steps: determining the processing tracks of N focal points on the target processing plane, dividing each processing track into M segments, taking out the position points of the focal points from each segment, and constructing an M×N position point matrix according to the processing direction; taking out the position points of each row from the position point matrix in turn for complex amplitude encoding to obtain M holographic phase images; constructing a femtosecond laser processing system containing a spatial light modulator, and dynamically loading M holographic phase images through the spatial light modulator to obtain N processing tracks for N focal points to simultaneously process optical waveguides on the target processing plane. The present invention controls the number, thickness and path of optical waveguides by changing the number of focal points, the intensity of each focal point and the moving path of each focal point, thereby reducing the number of iterations in the production process of silicon photonic chips.

Description

Technical Field

[0001] The present invention belongs to the technical field of silicon photonic chip production, and specifically relates to a high-speed parallel laser three-dimensional photonic wire bonding method and system based on multi-focus control. Background Art

[0002] In the field of semiconductor chips, as the performance of electronic technology gradually approaches physical limits, the growth in data transmission demand has caused traditional electronic chips to face bottleneck problems such as bandwidth, power consumption and latency. Optoelectronic chips have become important development chips with advantages such as high speed and low power consumption. Silicon photonic chips, as a type of optoelectronic chips, combine the advantages of microelectronics and optoelectronics. However, domestic silicon photonic chips still face challenges in key technologies, especially in coupling and packaging technologies.

[0003] Traditional coupling and packaging technologies are costly, difficult, and time-consuming, and require high-precision alignment, which to some extent limits the application and development of silicon photonic chips. New technologies such as laser nano 3D direct writing and photon wire bonding, namely photon bridging technology, can solve these problems to a certain extent. Among them, photon bridging technology processes three-dimensional optical waveguide structures on optoelectronic devices through laser three-dimensional nanofabrication, realizes efficient coupling and connection between optical chips and optical fibers, and greatly simplifies the manufacturing process of optical systems. Especially with the development of femtosecond laser technology, it has become possible to process extremely small structures in three-dimensional space, but the existing femtosecond laser 3D processing methods rely on expensive high-precision mechanical equipment and use a single focus for movement and scanning, resulting in high cost, slow processing speed, and low efficiency. To solve this problem, spatial light modulators (SLMs) are introduced to modify the incident light field and improve processing efficiency. Specifically, by loading the computational holographic phase map into the spatial light modulator (SLM), the femtosecond laser can be modulated into multiple focuses, realizing flexible modulation of the multi-focus array and processing structure, thereby improving processing speed and efficiency.

[0004] However, the algorithms used in existing femtosecond laser 3D processing methods, such as the weighted Gerchberg-Saxton (WGS) algorithm and the Gerchberg-Saxton (GS) algorithm, have disadvantages such as many iterations, long calculation time, and poor uniformity when producing holographic phase images under high digital aperture focusing systems. In addition, traditional spatial light modulator (SLM) applications are usually limited to generating multi-focus spot arrays or patterns, which limits the versatility and application range of spatial light modulator (SLM). Summary of the invention

[0005] In a first aspect, an embodiment of the present application provides a high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control, comprising the following steps:

[0006] S1. Determine the processing trajectories of N focal points on the target processing plane, divide each processing trajectory into M segments, take out the position points of the focal points from each segment, and construct an M×N position point matrix according to the processing direction;

[0007] S2. Take out the position points of each row from the position point matrix in turn and perform complex amplitude encoding to obtain M holographic phase images;

[0008] S3. Construct a femtosecond laser processing system containing a spatial light modulator, and dynamically load M holographic phase images through the spatial light modulator to obtain N processing trajectories for performing optical waveguide processing at N focal points on the target processing plane at the same time.

[0009] Furthermore, the specific steps of step S1 are as follows:

[0010] S11. Determine N processing trajectories on the target processing plane according to the processing requirements, and assign a focus to each processing trajectory;

[0011] S12. Determine the moving direction of the focus on each trajectory as the processing direction;

[0012] S13. Divide each processing trajectory into M segments evenly according to the processing direction, and encode each segment;

[0013] S14. Take the midpoint from each segment of each processing trajectory as the focal point;

[0014] S15. construct an M×N matrix and initialize it;

[0015] S16. Fill each position point into an M×N matrix according to the processing direction, wherein each column is set to correspond to a different position point of a focus, and each row corresponds to a position point with the same code in different foci, to obtain an M×N position point matrix.

[0016] Furthermore, the specific steps of step S2 are as follows:

[0017] S21. Take out the starting position point of each focus from the position point matrix according to the processing direction to obtain the current set of position points;

[0018] S22. Perform complex amplitude encoding on the current set of position points to obtain a holographic phase map;

[0019] S23. Determine whether the position points of each row in the position point matrix are encoded;

[0020] If yes, go to step S3;

[0021] If not, proceed to step S24;

[0022] S24. Take out the position points of each focus in the next row from the position point matrix according to the processing direction as the current group of position points, and return to step S22.

[0023] Furthermore, the specific steps of step S22 are as follows:

[0024] S221. Obtain the coordinates of the current set of position points, and calculate the pure phase distribution of the focus corresponding to each position point using the following formula:

[0025]

[0026] in, is the wavelength; A is the amplitude; is the aperture radius; is the refractive index of the medium in which the objective is immersed; , is the position coordinate of the rear focal plane of the objective lens; , It is the relative displacement component in the x and y directions of the focal plane compared with the original focal spot of the objective lens without phase modulation;

[0027] S222. The complex amplitude distribution equation of the incident field is calculated according to the pure phase distribution of each focus at the position point by the following formula:

[0028]

[0029] Where n is the focus number, N is the number of focuses, i is the imaginary unit, and m is the topological charge number;

[0030] S223. The distribution equation of the incident field is expressed as the superposition of the following two equal-amplitude pure phase functions, and two phases are obtained:

[0031]

[0032] in, , is the spatial phase distribution function The maximum value of, the relationship between amplitude and phase is expressed as:

[0033]

[0034] ;

[0035] S224. Obtain two complementary checkerboard functions, a first checkerboard function and a second checkerboard function, use the first checkerboard function to encode one phase, and use the second checkerboard function to encode another phase. The specific encoding formula is as follows:

[0036]

[0037]

[0038] in, Indicates the pitch angle The symplectic function, is the period of the two-dimensional binary grating, and represents the diffraction order.

[0039] Furthermore, before step S221, the following steps are also included:

[0040] SA1. Determine whether the intensity of each focus is equal;

[0041] If yes, go to step S221;

[0042] If not, proceed to step SA2;

[0043] SA2. Obtain the intensity ratio of each focus, and set the amplitude in the pure phase distribution corresponding to the position point according to the intensity ratio of each focus.

[0044] Furthermore, the specific steps of step S3 are as follows:

[0045] S31. Construct a femtosecond laser processing system for generating a multi-track optical waveguide, set an incident light path from the femtosecond laser to the spatial light modulator, a modulation light path from the spatial light modulator to the objective lens, and a focusing light path from the objective lens to the target processing plane;

[0046] S32. The spatial light modulator sequentially loads each holographic phase image according to a preset frequency, and modulates the incident light of the femtosecond laser;

[0047] S33. The objective lens focuses the modulated light onto the target processing plane, and dynamically moves N focal points according to the loading order of the holographic phase image to obtain N processing tracks.

[0048] Furthermore, the specific steps of step S31 are as follows:

[0049] S311. A half-wave plate, a Glan laser polarizer, a beam expander, a polarizer, and a reflector are sequentially arranged in the incident light path between the femtosecond laser and the spatial light modulator on the incident light path;

[0050] S312. A dichroic mirror is provided in the modulated light path between the spatial light modulator and the objective lens;

[0051] S313. Determine whether it is necessary to filter out zero-order light;

[0052] If yes, go to step S314;

[0053] If not, proceed to step S315;

[0054] S314. Setting a filtering light path between the spatial light modulator and the dichroic mirror;

[0055] S315. A light source is also provided at the lower part of the target processing plane, and an imaging lens and a CCD are provided on the optical path of the reverse extension line of the reflected light of the dichroic mirror. The light source, the imaging lens and the CCD form an observation optical path.

[0056] Furthermore, in step S314, the filtering optical path includes a first Fourier lens, a filtering aperture, and a second Fourier lens which are arranged in sequence.

[0057] Furthermore, the specific steps of step S32 are as follows:

[0058] S321. After loading a holographic phase image, the spatial light modulator modulates the incident light according to the complex amplitude coding;

[0059] S322. The first Fourier lens converts the modulated incident light into the frequency domain;

[0060] S323. The incident light in the frequency domain is filtered out of the zero-order spectrum by the filter aperture, and then transformed by the second Fourier lens to obtain the reconstructed complex amplitude.

[0061] In a second aspect, the present application also provides a high-speed parallel laser three-dimensional photon wire bonding system based on multi-focus control, comprising:

[0062] The position point matrix construction module is used to determine the processing trajectories of N focal points on the target processing plane, divide each processing trajectory into M segments, take the position points of the focal points from each segment, and construct an M×N position point matrix according to the processing direction;

[0063] A complex amplitude coding module is used to sequentially take out the position points of each row from the position point matrix for complex amplitude coding to obtain M holographic phase images;

[0064] The parallel processing module is used to construct a femtosecond laser processing system containing a spatial light modulator, and dynamically load M holographic phase images through the spatial light modulator to obtain N processing tracks for performing optical waveguide processing at N focal points on the target processing plane at the same time.

[0065] It can be seen from the above technical solutions that the present invention has the following advantages:

[0066] The high-speed parallel laser three-dimensional photonic wire bonding method and system based on multi-focus control provided by the present application realizes scanning processing of multiple focuses along different trajectories at the same time, and can control the number, thickness and path of optical waveguides by changing the number of focuses, the intensity of each focus and the moving path of each focus, thereby overcoming the limitation that a single focus can only process one optical waveguide at a time, reducing the number of iterations in the production process of silicon photonic chips, and only requiring one calculation, and can also control the optical waveguide to achieve uniform thickness. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0068] Figure 1 The present invention is a schematic flow chart of a high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control.

[0069] Figure 2 It is a schematic diagram of complex amplitude coding of the present invention.

[0070] Figure 3 It is a schematic diagram of the femtosecond laser processing system of the present invention.

[0071] Figure 4 The motion trajectories of the focus of three groups of identical curves, three groups of identical straight lines and three groups of different curves of the present invention and the points exposed at different times on the motion trajectories, wherein (a) is five focus per group, (b) is three focus per group, and (c) is seven focus per group.

[0072] Figure 5 It is a simulation schematic diagram of the front and rear focal points of the amplitude modulation of the present invention.

[0073] Figure 6 It is a schematic diagram of the high-speed parallel laser three-dimensional photonic wire bonding system based on multi-focus control of the present invention.

[0074] Specific reference numerals

[0075] 1. Femtosecond laser; 2. Half-wave plate; 3. Glan laser polarizer; 4. Beam expander; 5. Polarizer; 6. Reflector; 7. Spatial light modulator; 8. First Fourier lens; 9. Filter aperture; 10. Second Fourier lens; 11. Dichroic mirror; 12. Objective lens; 13. Target processing plane; 14. Light source; 15. Imaging lens; 16. CCD. DETAILED DESCRIPTION

[0076] In the specific steps of the high-speed parallel laser three-dimensional photonic wire bonding method based on multi-focus control, which will be described in detail below, various embodiments of the present disclosure will be described more comprehensively. The present disclosure may have various embodiments, and adjustments and changes may be made therein. However, it should be understood that there is no intention to limit the various embodiments of the present disclosure to the specific embodiments disclosed herein, but rather the present disclosure should be understood to cover all adjustments, equivalents and / or alternatives that fall within the spirit and scope of the various embodiments of the present disclosure.

[0077] For example, in the evolution of semiconductor chip technology, electronic technology is gradually reaching the limits of physical performance, resulting in traditional electronic chips facing severe challenges such as limited bandwidth, excessive power consumption and increased latency when dealing with the growing demand for data transmission. In this context, optoelectronic chips are at the forefront of chip development with their high-speed transmission and low power consumption. Silicon photonic chips, as an important branch of optoelectronic chips, cleverly combine the dual advantages of microelectronics and optoelectronics. However, the development of domestic silicon photonic chips is not a smooth road, especially in coupling and packaging technology, which still faces many difficulties.

[0078] Traditional coupling and packaging methods are not only costly, complex and time-consuming, but also rely on high-precision alignment technology, which undoubtedly brings considerable obstacles to the application expansion and industrial upgrading of silicon photonic chips. In order to break this deadlock, the industry has begun to explore new technologies such as laser nano 3D direct writing technology and photon wire bonding (also known as photon bridging). Among them, photon bridging technology uses laser three-dimensional nanoscale manufacturing to accurately construct a three-dimensional optical waveguide structure on the surface of optoelectronic devices, realizing efficient and convenient connection between optical chips and optical fibers, greatly simplifying the manufacturing process of optical systems. In particular, with the rapid development of femtosecond laser technology, it has become possible to process tiny structures in three-dimensional space.

[0079] However, current femtosecond laser 3D processing technology still relies on expensive high-precision mechanical equipment, and usually adopts a single-point focus scanning method, which leads to high processing costs, slow speed and low efficiency. In order to overcome this problem, researchers introduced a spatial light modulator (SLM) to optimize the processing process by adjusting the incident light field. Specifically, by loading the computer-generated holographic phase image into the SLM, the femtosecond laser can be modulated into a multi-focus mode, thereby achieving flexible control of the multi-focus array and processing structure, significantly improving the processing speed and efficiency.

[0080] However, it is worth noting that existing femtosecond laser 3D processing algorithms, such as the weighted Gerchberg-Saxton (WGS) algorithm and the Gerchberg-Saxton (GS) algorithm, have problems such as numerous iterations, long calculation time, and insufficient uniformity when generating holographic phase images under high digital aperture focusing systems. In addition, traditional SLM applications are often limited to generating multi-focus spot arrays or specific patterns, which to some extent limits the versatility and application areas of SLM.

[0081] In response to the above technical problems, the present embodiment provides a high-speed parallel laser three-dimensional photonic wire bonding method based on multi-focus control. By constructing a position point matrix, performing complex amplitude encoding, constructing a femtosecond laser processing system, and optimizing the filtering optical path, high-speed parallel processing of multiple focuses on the target processing plane is achieved, the number of iterations in the production process of silicon photonic chips is reduced, and uniform thickness of the optical waveguide can be achieved.

[0082] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0083] See also Figure 1 The figure is a flow chart of a high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control in a specific embodiment, the method comprising the following steps:

[0084] S1. Determine the machining trajectories of N focal points on the target machining plane 13, divide each machining trajectory into M segments, take out the position points of the focal points from each segment, and construct an M×N position point matrix according to the machining direction;

[0085] S2. Take out the position points of each row from the position point matrix in turn and perform complex amplitude encoding to obtain M holographic phase images;

[0086] S3. Construct a femtosecond laser processing system containing a spatial light modulator 7, and dynamically load M holographic phase images through the spatial light modulator 7 to obtain N focal points and N processing tracks for performing optical waveguide processing on the target processing plane 13 at the same time.

[0087] This embodiment realizes high-speed parallel processing of multiple focal points on the target processing plane 13 by constructing a position point matrix and performing complex amplitude encoding, thereby significantly improving the processing speed and efficiency.

[0088] Further, as a refinement and extension of the specific implementation of the above embodiment, in order to fully illustrate the specific implementation process in this embodiment, another high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control is provided, and the method includes:

[0089] S1. Determine the processing trajectories of N focal points on the target processing plane 13, divide each processing trajectory into M segments, take out the position points of the focal points from each segment, and construct an M×N position point matrix according to the processing direction; the specific steps of step S1 are as follows:

[0090] S11. Determine N processing trajectories on the target processing plane 13 according to the processing requirements, and assign a focus to each processing trajectory;

[0091] S12. Determine the moving direction of the focus on each trajectory as the processing direction;

[0092] S13. Divide each processing trajectory into M segments evenly according to the processing direction, and encode each segment;

[0093] S14. Take the midpoint from each segment of each processing trajectory as the focal point;

[0094] S15. construct an M×N matrix and initialize it;

[0095] S16. Fill each position point into an M×N matrix according to the processing direction, wherein each column is set to correspond to a different position point of a focus, and each row corresponds to a position point with the same code in different focuses, to obtain an M×N position point matrix;

[0096] It should be noted that by determining the processing trajectory, allocating the focus, dividing the trajectory segments, and extracting the position points, accurate position information is provided for the subsequent complex amplitude encoding;

[0097] S2. Take out the position points of each row from the position point matrix in turn for complex amplitude encoding to obtain M holographic phase images; the specific steps of step S2 are as follows:

[0098] S21. Take out the starting position point of each focus from the position point matrix according to the processing direction to obtain the current set of position points;

[0099] S22. Perform complex amplitude encoding on the current set of position points to obtain a holographic phase map;

[0100] S23. Determine whether the position points of each row in the position point matrix are encoded;

[0101] If yes, go to step S3;

[0102] If not, proceed to step S24;

[0103] S24. Take out the position points of each focus in the next row from the position point matrix according to the processing direction as the current set of position points, and return to step S22;

[0104] It should be noted that the position points of each row are sequentially taken out from the position point matrix for complex amplitude encoding, and the generation of the holographic phase image is controlled by judging whether the encoding is completed, which provides a basis for high-speed parallel processing;

[0105] S3. Construct a femtosecond laser processing system containing a spatial light modulator 7, and dynamically load M holographic phase images through the spatial light modulator 7 to obtain N focal points for performing N processing tracks of optical waveguide processing on the target processing plane 13 at the same time; the specific steps of step S3 are as follows:

[0106] S31. Constructing a femtosecond laser processing system for generating a multi-track optical waveguide, setting the incident light path from the femtosecond laser 1 to the spatial light modulator 7, the modulation light path from the spatial light modulator 7 to the objective lens 12, and the focusing light path from the objective lens 12 to the target processing plane 13;

[0107] S32. The spatial light modulator 7 sequentially loads each holographic phase image according to a preset frequency, and modulates the incident light of the femtosecond laser 1;

[0108] S33. The objective lens 12 focuses the modulated light onto the target processing plane 13, and performs N dynamic movement of the focal points according to the loading order of the holographic phase image to obtain N processing tracks;

[0109] It should be noted that by constructing a femtosecond laser processing system that produces multi-track optical waveguides, hardware support is provided for achieving high-speed parallel processing.

[0110] In an embodiment of the present invention, based on step S22, a possible embodiment is given below to illustrate its specific implementation scheme in a non-limiting manner.

[0111] The specific steps of step S22 are as follows:

[0112] S221. Obtain the coordinates of the current set of position points, and calculate the pure phase distribution of the focus corresponding to each position point using the following formula:

[0113]

[0114] in, is the wavelength; A is the amplitude; is the aperture radius; is the refractive index of the medium in which the objective is immersed; , is the position coordinate of the rear focal plane of the objective lens; , It is the relative displacement component in the x and y directions of the focal plane compared with the original focal spot of the objective lens without phase modulation;

[0115] S222. The complex amplitude distribution equation of the incident field is calculated according to the pure phase distribution of each focus at the position point by the following formula:

[0116]

[0117] Where n is the focus number, N is the number of focuses, i is the imaginary unit, and m is the topological charge number, where m=0;

[0118] S223. The distribution equation of the incident field is expressed as the superposition of the following two equal-amplitude pure phase functions, and two phases are obtained:

[0119]

[0120] in, , is the spatial phase distribution function The maximum value of, the relationship between amplitude and phase is expressed as:

[0121]

[0122] ;

[0123] S224. Obtain two complementary checkerboard functions, a first checkerboard function and a second checkerboard function, use the first checkerboard function to encode one phase, and use the second checkerboard function to encode another phase. The specific encoding formula is as follows:

[0124]

[0125]

[0126] in, Indicates the pitch angle The symplectic function, is the period of the two-dimensional binary grating, and represents the diffraction order;

[0127] It should be noted that by describing the steps of calculating the pure phase distribution, calculating the complex amplitude distribution equation, obtaining two phases, and encoding using the checkerboard function, a technical support is provided for generating a high-quality holographic phase image. The entire complex amplitude encoding process is as follows: Figure 2 shown.

[0128] It should be noted that, before step S221, the following steps are also included:

[0129] SA1. Determine whether the intensity of each focus is equal;

[0130] If yes, go to step S221;

[0131] If not, proceed to step SA2;

[0132] SA2. Obtain the intensity ratio of each focus, and set the amplitude in the pure phase distribution corresponding to the position point according to the intensity ratio of each focus;

[0133] It should be noted that not only the number of foci can be controlled, but also the intensity of the corresponding foci can be adjusted by changing the amplitude of the foci, e.g. Figure 5 As shown, Figure 5 The left part of shows the simulated images of light spots with three, five, and seven focal points when no amplitude modulation is performed; Figure 5 The right part of shows the simulated images of the corresponding focuses after amplitude modulation; among them, the intensity ratio of three focuses is 8:6:10, the intensity ratio of five focuses is 10:6:8:6:10, and the intensity ratio of seven focuses is 10:6:8:10:6:10:8;

[0134] Before complex amplitude encoding, a step is added to determine whether the intensity of each focus is equal, and the amplitude is set according to the intensity ratio, thereby ensuring that the processing effect of each focus is consistent.

[0135] In an embodiment of the present invention, based on step S31 and step S32, a possible embodiment is given below to illustrate its specific implementation scheme in a non-limiting manner.

[0136] The specific steps of step S31 are as follows:

[0137] S311. A half-wave plate 2, a Glan laser polarizer 3, a beam expander 4, a polarizer 5, and a reflector 6 are sequentially arranged in the incident light path between the femtosecond laser 1 and the spatial light modulator 7 on the incident light path;

[0138] S312. A dichroic mirror 11 is provided in the modulated light path between the spatial light modulator 7 and the objective lens 12;

[0139] S313. Determine whether it is necessary to filter out zero-order light;

[0140] If yes, go to step S314;

[0141] If not, proceed to step S315;

[0142] S314. A filtering light path is provided between the spatial light modulator 7 and the dichroic mirror 11;

[0143] S315. A light source 14 is also provided at the lower portion of the target processing plane 13, and an imaging lens 15 and a CCD 16 are provided on the optical path of the reverse extension line of the reflected light of the dichroic mirror 11, and the light source 14, the imaging lens 15 and the CCD 16 form an observation optical path;

[0144] It should be noted that the specific construction steps of the femtosecond laser processing system for setting the incident light path, the modulation light path, and the observation light path provide detailed guidance for the construction of the system. Specifically, the femtosecond laser processing system is as follows: Figure 3 As shown;

[0145] The specific steps of step S32 are as follows:

[0146] S321. After the spatial light modulator 7 is loaded with a holographic phase image, the incident light is modulated according to the complex amplitude coding;

[0147] S322. The first Fourier lens 8 converts the modulated incident light into the frequency domain;

[0148] S323. The incident light in the frequency domain is filtered out by the filter aperture 9 to remove the zero-order spectrum, and then transformed by the second Fourier lens 10 to obtain a reconstructed complex amplitude;

[0149] It should be noted that the first Fourier lens 8, the filtering aperture 9 and the second Fourier lens 10 are arranged in the filtering light path, which effectively filters out the zero-order light and improves the processing quality.

[0150] In the specific experiment, based on the femtosecond laser processing system, the spatial light modulator 7 can be used to dynamically load the phase image and realize multi-focus dynamic micro-nano processing. In the experiment, we use a laser with a wavelength of 515nm as the incident light and use the spatial light modulator 7 to modulate the back aperture plane of the 100×NA1.3 oil immersion objective lens.

[0151] Drop photoresist on a clean glass sheet, and after vacuum treatment, place the glass sheet on a stage, and focus the laser light modulated by the spatial light modulator 7 and filtered by the filter optical path on the contact surface of the glass sheet and the photoresist through the objective lens 12 to achieve dynamic processing. After processing, the glass sheet is developed to remove the uncured photoresist and leave the processed structure;

[0152] like Figure 4 As shown in , three groups of multi-focus arrays are designed, namely 3×1, 5×1 and 7×1, and three corresponding groups of phase images are generated; Figure 4As shown in (a), five focal points are generated in each group, and the distance between each focal point is designed to be 20μm. Among them, five identical straight lines, five identical curves and five different curves are designed; each trajectory has a corresponding set of phase maps, and the corresponding three sets of phase maps are dynamically loaded using the program of the spatial light modulator 7 at a frequency of 10Hz, and three sets of trajectory lines are obtained. The program of the spatial light modulator 7 loads the 1st, 51st, 101st, 151st, and 200th phase maps in sequence, so that the focus can be controlled to move to five positions in sequence and expose at these positions, and three sets of dotted trajectory lines are obtained. The focal spacing is designed to be 20μm, so the line spacing of the five straight lines is 20μm, the line spacing of the five identical curves is also 20μm, and only the processing starting position on the five different curves is the same as the designed focal spacing. In Figures 4 (b) and (c), the number of focal points is three and seven, respectively, and the focal distances are designed to be 30μm and 12μm, respectively.

[0153] Taking the parallel processing of three focuses as an example, by dynamically loading the phase map in the x direction, the three focuses are controlled to move along the central trajectory of the optical waveguide at the same time. The moving path of the focus is controlled by piezoelectric and scanning galvanometers, and a disk consisting of concentric circles is written on the yz plane. The center of each disk is located on the central trajectory of the waveguide, and each disk is perpendicular to the central trajectory of the waveguide. Each time a phase map is loaded, the three focuses move once in their respective motion trajectories according to the set step size. After writing a disk at the previous position, the next phase map is loaded, the focus moves to the next position, and continues to write a concentric disk. This process is repeated, and the optical waveguide eventually consists of multiple concentric disks. After the spatial light modulator 7 modulates a laser beam into multiple focuses, each focus can execute the processing path at different positions at the same time to achieve parallel processing of multiple optical waveguides.

[0154] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0155] like Figure 6 As shown, the following is an embodiment of a high-speed parallel laser three-dimensional photonic wire bonding system based on multi-focus control provided by an embodiment of the present disclosure, which system and the high-speed parallel laser three-dimensional photonic wire bonding method based on multi-focus control of the above-mentioned embodiments belong to the same inventive concept, and the details not fully described in the embodiment of the high-speed parallel laser three-dimensional photonic wire bonding system based on multi-focus control can refer to the embodiment of the above-mentioned high-speed parallel laser three-dimensional photonic wire bonding method based on multi-focus control.

[0156] The system includes:

[0157] A position point matrix construction module is used to determine the processing trajectories of N focal points on the target processing plane 13, divide each processing trajectory into M segments, take out the position points of the focal points from each segment, and construct an M×N position point matrix according to the processing direction;

[0158] A complex amplitude coding module is used to sequentially take out the position points of each row from the position point matrix for complex amplitude coding to obtain M holographic phase images;

[0159] The parallel processing module is used to construct a femtosecond laser processing system containing a spatial light modulator 7, and dynamically load M holographic phase images through the spatial light modulator 7 to obtain N focal points and N processing tracks for performing optical waveguide processing on the target processing plane 13 at the same time.

[0160] The high-speed parallel laser three-dimensional photonic wire bonding system based on multi-focus control in this embodiment realizes the automation of the entire process from position point matrix construction to parallel processing through modular design, thereby improving processing efficiency and accuracy.

[0161] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control, characterized in that: The steps include: S1. Determine the processing trajectories of N focal points on the target processing plane, divide each processing trajectory into M segments, take out the position points of the focal points from each segment, and construct an M×N position point matrix according to the processing direction; S2. Take out the position points of each row from the position point matrix in turn and perform complex amplitude encoding to obtain M holographic phase images; S2 is as follows: S21. Take out the starting position point of each focus from the position point matrix according to the processing direction to obtain the current set of position points; S22. Perform complex amplitude encoding on the current set of position points to obtain a holographic phase map; S22 is as follows: SA1. Determine whether the intensity of each focus is equal; If yes, go to S221; If not, proceed to SA2; SA2. Obtain the intensity ratio of each focus, and set the amplitude in the pure phase distribution corresponding to the position point according to the intensity ratio of each focus; S221. Obtain the coordinates of the current set of position points, and calculate the pure phase distribution of the focus corresponding to each position point using the following formula: in, is the wavelength; A is the amplitude; is the aperture radius; is the refractive index of the medium in which the objective is immersed; , is the position coordinate of the rear focal plane of the objective lens; , It is the relative displacement component in the x and y directions of the focal plane compared with the original focal spot of the objective lens without phase modulation; S222. Calculate the complex amplitude distribution equation of the incident field according to the pure phase distribution of each focus at the position point by the following formula; Where n is the focus number, N is the number of focuses, i is the imaginary unit, and m is the topological charge number; S23. Determine whether the position points of each row in the position point matrix are encoded; If yes, go to S3; If not, proceed to S24; S24. Take out the position points of each focus in the next row from the position point matrix according to the processing direction as the current set of position points, and return to S22; S3. Construct a femtosecond laser processing system containing a spatial light modulator, and dynamically load M holographic phase images through the spatial light modulator to obtain N processing trajectories for performing optical waveguide processing at N focal points on the target processing plane at the same time.

2. The high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control according to claim 1, characterized in that: The specific steps of step S1 are as follows: S11. Determine N processing trajectories on the target processing plane according to the processing requirements, and assign a focus to each processing trajectory; S12. Determine the moving direction of the focus on each trajectory as the processing direction; S13. Divide each processing trajectory into M segments evenly according to the processing direction, and encode each segment; S14. Take the midpoint from each segment of each processing trajectory as the focal point; S15. construct an M×N matrix and initialize it; S16. Fill each position point into an M×N matrix according to the processing direction, wherein each column is set to correspond to a different position point of a focus, and each row corresponds to a position point with the same code in different foci, to obtain an M×N position point matrix.

3. The high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control according to claim 2, characterized in that: Step S22 also includes the following steps: S223. The distribution equation of the incident field is expressed as the superposition of the following two equal-amplitude pure phase functions, and two phases are obtained: in, , is the spatial phase distribution function The maximum value of, the relationship between amplitude and phase is expressed as: ； S224. Obtain two complementary checkerboard functions, a first checkerboard function and a second checkerboard function, use the first checkerboard function to encode one phase, and use the second checkerboard function to encode another phase. The specific encoding formula is as follows: in, Indicates the pitch angle The symplectic function, is the period of the two-dimensional binary grating, and represents the diffraction order.

4. The high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control as claimed in claim 3, characterized in that: The specific steps of step S3 are as follows: S31. Construct a femtosecond laser processing system for generating a multi-track optical waveguide, set an incident light path from the femtosecond laser to the spatial light modulator, a modulation light path from the spatial light modulator to the objective lens, and a focusing light path from the objective lens to the target processing plane; S32. The spatial light modulator sequentially loads each holographic phase image according to a preset frequency to modulate the incident light of the femtosecond laser; S33. The objective lens focuses the modulated light onto the target processing plane, and dynamically moves N focal points according to the loading order of the holographic phase image to obtain N processing tracks.

5. The high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control according to claim 4, characterized in that: The specific steps of step S31 are as follows: S311. A half-wave plate, a Glan laser polarizer, a beam expander, a polarizer, and a reflector are sequentially arranged in the incident light path between the femtosecond laser and the spatial light modulator on the incident light path; S312. A dichroic mirror is provided in the modulated light path between the spatial light modulator and the objective lens; S313. Determine whether it is necessary to filter out zero-order light; If yes, go to step S314; If not, proceed to step S315; S314. Setting a filtering light path between the spatial light modulator and the dichroic mirror; S315. A light source is also provided at the lower part of the target processing plane, and an imaging lens and a CCD are provided on the optical path of the reverse extension line of the reflected light of the dichroic mirror. The light source, the imaging lens and the CCD form an observation optical path.

6. The high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control as claimed in claim 5, characterized in that: In step S314, the filtering optical path includes a first Fourier lens, a filtering aperture, and a second Fourier lens which are arranged in sequence.

7. The high-speed parallel laser three-dimensional photon wire bonding method based on multi-focus control according to claim 6, characterized in that: The specific steps of step S32 are as follows: S321. After loading a holographic phase image, the spatial light modulator modulates the incident light according to the complex amplitude coding; S322. The first Fourier lens converts the modulated incident light into the frequency domain; S323. The incident light in the frequency domain is filtered out of the zero-order spectrum by the filter aperture, and then transformed by the second Fourier lens to obtain the reconstructed complex amplitude.

8. A system using the high-speed parallel laser three-dimensional photonic wire bonding method based on multi-focus control according to any one of claims 1 to 7, characterized in that: include: The position point matrix construction module is used to determine the processing trajectories of N focal points on the target processing plane, divide each processing trajectory into M segments, take the position points of the focal points from each segment, and construct an M×N position point matrix according to the processing direction; A complex amplitude coding module is used to sequentially take out the position points of each row from the position point matrix for complex amplitude coding to obtain M holographic phase images; The parallel processing module is used to construct a femtosecond laser processing system containing a spatial light modulator, and dynamically load M holographic phase images through the spatial light modulator to obtain N processing tracks for performing optical waveguide processing at N focal points on the target processing plane at the same time.

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