Micromechanical dynamically tunable beam steering device and method of manufacturing thereof

Abstract

The application discloses a dynamic adjustable beam deflection device based on micro-mechanics and a preparation method thereof, relates to the technical field of electromagnetic wave beam deflection, and comprises a plurality of beam deflection components arranged in a matrix, wherein the beam deflection component is composed of a metasurface layer and a silicon wafer layer, the metasurface layer is arranged at the bottom of the silicon wafer layer, the metasurface layer comprises a polyimide substrate arranged at the bottom of the silicon wafer layer, a backplate gold is arranged on one side of the polyimide substrate, a cross structure is arranged in the polyimide substrate, and a gold resonance layer structure frame is arranged on the side of the polyimide substrate away from the backplate gold. The device has the advantages of simple structure, simple preparation process, high beam regulation and control efficiency, fast working state switching speed of the device, simple switching mode, fast beam regulation and control opening and closing through simple operation, strong expandability in the future, and good application prospect in the field of beam regulation and control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electromagnetic wave beam deflection, in particular to a dynamically adjustable beam deflection device based on micro-mechanical and a preparation method thereof. BACKGROUND

[0002] Terahertz communication, unlike traditional wireless communication, works in the terahertz frequency band and has a higher data transmission rate. The terahertz frequency band is relatively wide, and most of it has not been allocated for use. In addition, terahertz waves are harmless to the human body, so terahertz communication has broad application prospects.

[0003] Terahertz metasurfaces are planar arrays of micron-scale unit structures used to control the local phase and amplitude of scattered light fields, enabling subwavelength-scale waveforms to be regulated. Applications of terahertz metasurfaces include free-space wavefront shaping, multifunctional polarization conversion, holographic imaging, and so on.

[0004] It is of great practical significance to use terahertz metasurfaces in the field of beam steering. The terahertz frequency band has a wide bandwidth and is harmless to the human body, so it has great application prospects in the future. Terahertz beam steering devices have great application potential in the fields of terahertz communication and scanning and focusing.

[0005] Metasurfaces can flexibly and effectively regulate the polarization, amplitude, phase, polarization mode, and propagation mode of electromagnetic waves. Most of them are composed of artificial subwavelength unit structure arrays, have the advantages of low profile, light weight, and ease of use, but current tunable beam steering devices often have the disadvantages of complex preparation process, complex tuning method, and slow modulation rate.

[0006] There is currently no effective solution to the problems in the related art. SUMMARY

[0007] To overcome the above technical problems existing in the prior art, the present application proposes a dynamically adjustable beam deflection device based on micro-mechanical and a preparation method thereof.

[0008] To this end, the specific technical solutions adopted by the present application are as follows:

[0009] According to a first aspect of the present application, a dynamically adjustable beam deflection device based on micro-mechanical is provided, comprising a plurality of beam deflection components arranged in a matrix, the beam deflection component being composed of a metasurface layer and a silicon wafer layer, and the metasurface layer being arranged at the bottom of the silicon wafer layer.

[0010] Further, in order to fix the silicon wafer layer on the piezoelectric displacement table, the longitudinal distance between the silicon wafer layer and the metasurface layer is changed by the piezoelectric displacement table to realize the movement of the metasurface layer, and then the beam steering function is turned on and off, the metasurface layer comprises a polyimide substrate arranged at the bottom of the silicon wafer layer, the polyimide substrate is provided with a backplate gold on one side, the polyimide substrate is provided with a cross structure on the inside, and the polyimide substrate is provided with a gold resonant layer structure frame on the side away from the backplate gold.

[0011] Further, in order to have the characteristics of simple device structure and high beam steering efficiency, the working state of the device can be switched quickly and simply, and the beam steering can be turned on and off quickly through simple operation, the beam deflection components are arranged in a matrix, the resonant phase of the beam deflection component along the incident wave electric field direction meets the linear gradient change, the gold resonant layer structure frame and the backplate gold are both lossy metal layers, the thickness of the gold resonant layer structure frame and the backplate gold is microns, the silicon wafer layer is a high resistance silicon wafer, the thickness of the silicon wafer layer is microns, and the longitudinal relative position movement between the metasurface layer and the silicon wafer layer is realized by the piezoelectric displacement table.

[0012] According to a second aspect of the present application, a preparation method of a dynamically adjustable beam deflection device based on micro-mechanical is provided, the preparation method comprises:

[0013] The silicon substrate is cleaned, and after the cleaning is completed, a backplate gold thin film is grown on the surface of the silicon substrate by using a magnetron sputtering method;

[0014] A polyimide thin film is spin-coated on the backplate gold thin film, and the backplate gold thin film after spin-coating the polyimide thin film is placed at a preset temperature for drying;

[0015] The polyimide thin film after drying is spin-coated with photoresist and dried to obtain a sample after spin-coating photoresist, the sample is aligned and exposed with a mask by using a photoetching machine, after the exposure is completed, the sample is developed by using a positive photoresist developer, and the photoetching development effect is observed under a microscope;

[0016] After the periodic metal structure is grown on the surface of the sample by using the magnetron sputtering method, the sample is placed in an N-methyl solution for static soaking, the non-structure gold thin film layer on the surface of the sample is removed by using a plastic dropper, and the surface of the sample is sequentially cleaned with acetone, ethanol and water to obtain a metasurface layer;

[0017] The silicon wafer layer is placed on the support plate and aligned with the metasurface layer installed on the piezoelectric displacement table, so that the terahertz beam penetrates the silicon wafer layer and the support plate in sequence and irradiates the metasurface layer to obtain a beam deflection device.

[0018] Further, the preset temperature in the drying process of the back plate gold film after the spin coating of the polyimide film includes a first stage temperature, a second stage temperature, a third stage temperature and a fourth stage temperature:

[0019] The first stage temperature includes: rising from room temperature to 80 DEG C, the rising time is 20 minutes, and maintaining at 80 DEG C for 30 minutes;

[0020] The second stage temperature includes: rising from 80 DEG C to 140 DEG C, the rising time is 15 minutes, and maintaining at 140 DEG C for 30 minutes;

[0021] The third stage temperature includes: rising from 140 DEG C to 250 DEG C, the rising time is 25 minutes, and maintaining at 250 DEG C for 30 minutes;

[0022] The fourth stage temperature includes: rising from 250 DEG C to 320 DEG C, and maintaining at 320 DEG C for 2 hours.

[0023] Further, the thickness of the polyimide film in the spin coating of the polyimide film on the back plate gold film is 10 microns.

[0024] According to the third aspect of the present application, the application of the micro-mechanical based dynamically adjustable beam deflection device in beam deflection, beam focusing and holographic imaging is also provided.

[0025] The beam control device provided by the present application can realize the opening and closing of the rapid beam control function in the terahertz wave band, compared with the traditional beam control device, the device structure is simple, the preparation process is simple, the beam control efficiency is high, the working state switching speed of the device is fast, the switching mode is simple, the rapid beam control opening and closing can be realized through simple operation, the subsequent expandability is strong, and the device has good application prospect in the field of beam control. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0027] Figure 1 is a structure schematic diagram of the micro-mechanical based dynamically adjustable beam deflection device according to the embodiment of the present application;

[0028] Figure 2 is a top view of the metasurface layer in the micro-mechanical based dynamically adjustable beam deflection device according to the embodiment of the present application;

[0029] Figure 3 is a structural schematic diagram of a metasurface layer in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0030] Figure 4 is a flow chart of a preparation method of a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0031] Figure 5 is an effect diagram of holographic imaging in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0032] Figure 6 is a simulation curve of reflection amplitude of each beam deflection component when a 2bit structure is in a beam deflection function opening state in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0033] Figure 7 is a simulation curve of resonance phase of each beam deflection component when a 2bit structure is in a beam deflection function opening state in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0034] Figure 8 is a simulation curve of reflection amplitude of each beam deflection component when a 2bit structure is in a beam deflection function closing state in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0035] Figure 9 is a simulation curve of resonance phase of each beam deflection component when a 2bit structure is in a beam deflection function closing state in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0036] Figure 10 is a simulation curve of reflection amplitude of each ring cross structure when a 3bit structure is in a beam deflection function opening state in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0037] Figure 11 is a simulation curve of resonance phase of each ring cross structure when a 3bit structure is in a beam deflection function opening state in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application;

[0038] Figure 12 is a simulation curve of reflection amplitude of each ring cross structure when a 3bit structure is in a beam deflection function closing state in a micro-mechanical based dynamically adjustable beam deflection device according to an embodiment of the present application

[0039] Figure 13Resonance phase simulation curve of each ring cross structure in 3bit structure of micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application when the beam deflection function is in the off state;

[0040] Figure 14 Physical diagram of 3bit structure in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application;

[0041] Figure 15 Electric field distribution of 3bit structure in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application when the beam deflection function is in the on state;

[0042] Figure 16 Overall schematic diagram of beam deflection assembly in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application when the beam deflection function is in the on state;

[0043] Figure 17 Overall schematic diagram of beam deflection assembly in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application when the beam deflection function is in the off state;

[0044] Figure 18 Super surface layer structure schematic diagram of super lens focusing device in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application;

[0045] Figure 19 Phase distribution diagram of super lens focusing device in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application at different positions;

[0046] Figure 20 Effect diagram of focusing imaging of super lens focusing device in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application;

[0047] Figure 21 Super surface layer structure schematic diagram of holographic imaging device in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application;

[0048] Figure 22 Phase distribution diagram of holographic imaging device in micro-mechanical based dynamic adjustable beam deflection device according to an embodiment of the present application at different positions.

[0049] In the figure:

[0050] 1, beam deflection assembly; 101, super surface layer; 1011, polyimide substrate; 1012, backplate gold; 1013, cross structure; 1014, gold resonance layer structure frame; 102, silicon wafer layer. DETAILED DESCRIPTION

[0051] To further illustrate the embodiments, the present application provides accompanying drawings which form part of the disclosure and which are mainly used to illustrate the embodiments and can be used to explain the operating principles of the embodiments in conjunction with the relevant description. Those skilled in the art should be able to understand other possible implementations and advantages of the present application in conjunction with these contents. The components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0052] According to an embodiment of the present application, a micro-mechanical-based dynamically adjustable beam deflection device and a preparation method thereof are provided.

[0053] The present application will be further described in conjunction with the accompanying drawings and specific embodiments. As shown in the drawings, the micro-mechanical-based dynamically adjustable beam deflection device according to an embodiment of the present application comprises a plurality of beam deflection components 1 arranged in a matrix. The beam deflection component 1 is composed of a metasurface layer 101 and a silicon wafer layer 102, and the metasurface layer 101 is arranged at the bottom of the silicon wafer layer 102. Figures 1-3

[0054] In one embodiment, for the above-mentioned metasurface layer 101, the metasurface layer 101 comprises a polyimide substrate 1011 arranged at the bottom of the silicon wafer layer 102. The polyimide substrate 1011 is provided with a backplate gold 1012 on one side. The polyimide substrate 1011 is provided with a cross structure 1013 inside. The polyimide substrate 1011 is provided with a gold resonance layer structure frame 1014 on the side away from the backplate gold 1012. Thus, the backplate gold 1012 is attached to the piezoelectric displacement platform, and the silicon wafer layer 102 is fixed. By changing the position of the metasurface layer 101 through the piezoelectric displacement platform, the longitudinal distance between the silicon wafer layer 102 and the metasurface layer 101 is moved, and thus the opening and closing of the beam control function is realized.

[0055] It should be noted that, in order to realize the dynamic beam control in the terahertz wave band, the present application provides a micro-mechanical-based dynamically adjustable beam deflection device. The beam deflection device is composed of a plurality of beam deflection components 1 arranged in a certain rule. The beam deflection device comprises two parts, i.e. a metasurface layer 101 and a silicon wafer layer 102. By changing the size parameters of the cross structure 1013 in the beam deflection component 1, the beam deflection components 1 with different resonance structures have different phase responses. When the thickness of the air layer is at the design value, each beam deflection component 1 has a high reflection amplitude, and the reflection phase can cover 360°. In the actual test of the beam deflection component 1, the backplate gold 1012 is attached to the piezoelectric displacement platform, and the silicon wafer layer 102 is fixed. By changing the position of the metasurface layer 101 through the piezoelectric displacement platform, the longitudinal distance between the silicon wafer layer 102 and the metasurface layer 101 is moved, and thus the opening and closing of the beam control function is realized.

[0056] ​In one embodiment, for the above-mentioned beam deflection component 1, the beam deflection components 1 are arranged in a matrix, and the resonant phase of the beam deflection component 1 along the direction of the incident wave electric field changes in a linear gradient; the gold resonant layer structure frame 1014 and the back plate gold 1012 are both lossy metal layers, and the thickness of the gold resonant layer structure frame 1014 and the back plate gold 1012 is 0.2 microns; the silicon wafer layer 102 is a high resistance silicon wafer, and the thickness of the silicon wafer layer 102 is 50 microns, thereby having the characteristics of simple device structure and high beam control efficiency, and the device has fast switching speed and simple switching mode, and can realize fast beam control opening and closing through simple operation.

[0057] It should be noted that the resonant phase curve of the beam deflection component 1 is as shown in Figures 6-9 When the beam deflection component 1 is in the working state, the resonant phase curve of each beam deflection component 1 is as shown in Figure 6 and Figure 8 corresponding to 2bit and 3bit structures respectively, wherein the 2bit structure phase corresponds to 0°, 90°, 180° and 270°, a single period array contains four structures, and the amplitude and phase curves only have four curves, as shown in Figures 6-7

[0058] The 3bit structure phase corresponds to 0°, 45°, 90°, 135°, 180°, 225°, 270° and 315°, a single period array contains eight structures, and therefore the amplitude and phase curves have eight curves, as shown in Figures 8-9 The phase between the beam deflection components 1 presents a gradient distribution, and can cover a 360° phase gradient, and after changing the thickness of the air layer, the beam deflection component 1 becomes the off state, and the resonant phase curve of each beam deflection component 1 is as shown in Figure 7 and Figure 9 corresponding to 2bit and 3bit structures respectively, and the phase difference between the beam deflection components 1 is close to zero, and the resonant phases are almost consistent.

[0059] According to the second embodiment of the present application, as shown in Figure 4 a preparation method of a dynamically adjustable beam deflection device based on micro-mechanical is provided, and the preparation method comprises the following steps:

[0060] S1, cleaning the silicon substrate, and growing a back plate gold thin film on the surface of the silicon substrate by using a magnetron sputtering method after the cleaning is completed;

[0061] S2, spin coating a polyimide thin film on the back plate gold thin film, and placing the back plate gold thin film after the spin coating of the polyimide thin film in a preset temperature for drying;

[0062] ​S3, spin coating photoresist on the polyimide film after drying and drying to obtain a sample after spin coating photoresist, aligning the sample with the mask plate using a photoetching machine, exposing after exposure, developing by positive photoresist developer, and observing the photoetching effect under a microscope;

[0063] S4, after growing a periodic metal structure on the surface of the sample by a magnetron sputtering method, standing in an N-methyl solution for static soaking, removing the non-structure gold film layer on the surface of the sample by a plastic dropper, and sequentially cleaning the surface of the sample with acetone, ethanol and water to obtain a super surface layer;

[0064] S5, placing the silicon wafer layer on the support plate and aligning with the super surface layer mounted on the piezoelectric displacement table, so that the terahertz light beam penetrates the silicon wafer layer and the support plate in turn and irradiates the super surface layer to obtain a beam deflection device.

[0065] The preset temperature for drying the back plate gold film after spin coating the polyimide film includes a first stage temperature, a second stage temperature, a third stage temperature and a fourth stage temperature:

[0066] The first stage temperature includes: warming up from room temperature to 80℃, the warming up time is 20min, and maintaining at 80℃ for 30min;

[0067] The second stage temperature includes: warming up from 80℃ to 140℃, the warming up time is 15min, and maintaining at 140℃ for 30min;

[0068] The third stage temperature includes: warming up from 140℃ to 250℃, the warming up time is 25min, and maintaining at 250℃ for 30min;

[0069] The fourth stage temperature includes: warming up from 250℃ to 320℃, and maintaining at 320℃ for 2h.

[0070] In this embodiment, the preparation of the dynamic adjustable beam control device based on micro-mechanical includes:

[0071] Growing the back plate gold film: cleaning the silicon substrate, and growing the back plate gold film on the surface of the silicon substrate by a magnetron sputtering method. The magnetron sputtering method is a physical vapor deposition technology, which makes argon ions bombard the target surface by using the plasma constrained by the magnetic field in a high vacuum environment, sputters the target atoms or molecules to deposit on the substrate to form a thin film, and can realize precise control of the composition, structure and performance of the thin film. The process of growing the back plate gold film is: creating a vacuum environment, preparing the target and the substrate, generating plasma, ion bombardment of the target, thin film deposition, thin film property control, reactive sputtering and sampling.

[0072] Spin-coating polyimide film: spin-coat 10 microns thick polyimide film on the back plate gold film and set the corresponding temperature parameters for drying, the drying temperature parameters include: the first step, from room temperature to 80℃, the temperature rising time is 20min, then maintain at 80℃ for 30min, the second step, from 80℃ to 140℃, the temperature rising time is 15min, then maintain at 140℃ for 30min, the third step, from 140℃ to 250℃, the temperature rising time is 25min, then maintain at 250℃ for 30min, the fourth step, from 250℃ to 320℃, then maintain at 320℃ for 2 hours, the curing is completed.

[0073] Spin-coating photoresist: spin-coat photoresist on the dried polyimide film and dry, to get the sample after spin-coating photoresist.

[0074] UV exposure and development: place the sample on the photoetching machine and align with the mask plate, after exposure, develop with positive photoresist developer and observe the photoetching effect under the microscope.

[0075] Growth of periodic structure: use magnetron sputtering method to grow periodic metal structure on the surface of polyimide film, and stand in N-methyl solution for 24 hours or more.

[0076] Peeling: use a disposable plastic dropper to gently flush away the non-structure gold film on the surface of the sample, and clean with acetone, ethanol and water to get the super surface layer, and place the super surface layer under the microscope to observe the effect.

[0077] Build the final beam deflection device: place the silicon layer on the hole support plate, align with the super surface layer placed on the piezoelectric displacement table, and the terahertz beam passes through the hole of the silicon layer and the support plate and hits the super surface layer, to get the beam control deflection device with fast switching characteristics.

[0078] According to the third embodiment of the application, the application of the micro-mechanical based dynamically adjustable beam deflection device in beam deflection, beam focusing and holographic imaging is also provided.

[0079] In this embodiment, the application of the micro-mechanical based dynamically adjustable beam deflection device in beam deflection, beam focusing and holographic imaging includes:

[0080] Adjust the longitudinal distance between the silicon layer 102 and the super surface layer 101 by using the piezoelectric displacement table, to realize the control of the opening and closing of the beam control function, when the distance between the silicon layer 102 and the super surface layer 101 is the optimal design value, the device is in the working state of opening; with the increase of the distance between the super surface layer 101 and the silicon layer, the phase gradient between each beam deflection component 1 gradually disappears, and the phase difference between each beam deflection component 1 is basically zero, and the device is in the working state of closing.

[0081] CombineFigures 10 to 17 Detailed description of example one:

[0082] When the air layer thickness is in the value of the device beam deflection function opening state, at the working frequency point, each beam deflection component 1 has a higher reflection amplitude, and the resonant phase of each beam deflection component 1 changes linearly. Gradient, adjust the air layer thickness of the device, so that the device beam deflection function is closed, and the resonant phase of different beam deflection components 1 at the working frequency point is almost the same. The beam deflection component 1 is arranged and combined according to the resonant phase at the working frequency point in the polarization direction of the incident wave, and the beam deflection component 1 is copied and arranged in the direction perpendicular to the polarization direction of the incident wave, to form a 2bit and 3bit tunable beam deflection device, as shown in the physical diagram Figure 10 and Figure 13 When the device beam deflection function is opened, that is, in the state shown in Figure 16 , the incident wave is vertically incident, and after being controlled by the device, it is emitted at a certain angle. The electric field cross-section of the 2bit device is shown in Figure 10 , the deflection angle is consistent with the theoretical design, which is 53.25°. When the air layer thickness is changed, the device beam deflection function is closed, and the device is in the state shown in Figure 17 , at this time the incident wave is vertically incident and vertically emitted. The electric field cross-section is shown in Figure 12 , the device is equivalent to a mirror and no longer has a beam deflection function.

[0083] For a 3bit beam deflection device, the physical diagram is shown in Figure 13 , and the electric field cross-sections when the device function is opened and closed are shown in Figures 14-15 , respectively. Because of the different phase gradients, the deflection angle is different from that of the 2bit device. The deflection angle of the device in the beam deflection state is 23.62°.

[0084] In combination with Figures 18-20 Detailed description of example two:

[0085] According to the lens focusing optical path difference formula:

[0086] ;

[0087] Among them, ϕ ( x , y ) is the phase of the coordinate position, λ is the working wavelength, f is the focal length of the superlens, x , y is the position coordinate, the beam deflection component 1 with different phase gradients is arranged regularly to form a tunable device with beam focusing function. The overall structure of the super surface layer in the device is as followsFigure 18 As shown, the phase distribution of the beam deflection assembly 1 at different positions is regularly and periodically arranged from the center to the periphery. Figure 19 As shown, the focusing effect of the device is as follows: Figure 20 As shown, the tunable beam focusing device is located at the rightmost side, and the beam achieves the focusing effect at a position 5mm away from the device. After changing the thickness of the air layer, the phase arrangement changes, and the device no longer has the focusing effect, which meets the expected design.

[0088] In combination with Figure 5 and Figures 21-22 The third embodiment is described in detail.

[0089] According to the phase calculation formula of holographic imaging:

[0090] ;

[0091] wherein, ϕ ( x , y ) is the phase of the coordinate position, λ is the working wavelength, x , y ) is the position coordinate, x i , y i , z i is the position coordinate of the object point in the three-dimensional space, the corresponding phase distribution is calculated, and the tunable device with holographic imaging function is composed according to the phase arrangement of the beam deflection assembly 1. The overall structure of the super surface layer 101 in the device is as shown in Figure 21 , which is regularly arranged according to the calculated phase. The phase distribution diagram is as shown in Figure 22 , and the imaging effect of the final device is as shown in Figure 5 , which shows the expected image at the specified imaging position. After changing the thickness of the air layer, the phase distribution changes, and the device no longer has the imaging function, which meets the expected design simulation.

[0092] In addition, the super surface layer 101 is replaced by a tunable metasurface, which can greatly improve the tuning freedom of the device and expand the types of functions that the device can carry.

[0093] In summary, by means of the above technical solutions of the present application, the beam control device provided by the present application can realize the opening and closing of the fast beam control function in the terahertz wave band. Compared with the traditional beam control device, the device structure of the present application is simple, the preparation process is simple, the beam control efficiency is high, the working state switching speed of the device is fast, the switching mode is simple, the fast beam control opening and closing can be realized through simple operation, the subsequent expandability is strong, and the device has good application prospect in the field of beam control.

[0094] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "setting", "connecting", "fixing", "screwing" and the like should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited, the above-mentioned terms in the present application can be understood according to the specific meaning of the above-mentioned terms in the present application by those skilled in the art.

[0095] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. Micromechanical dynamic adjustable beam deflection device comprising a number of beam deflection components (1) in a matrix arrangement, characterized in that, The beam deflection component (1) is composed of a metasurface layer (101) and a silicon wafer layer (102), and the metasurface layer (101) is arranged at the bottom of the silicon wafer layer (102); The metasurface layer (101) comprises a polyimide substrate (1011) arranged at the bottom of the silicon wafer layer (102), one side of the polyimide substrate (1011) is provided with a backplate gold (1012), the inside of the polyimide substrate (1011) is provided with a cross structure (1013), and the side of the polyimide substrate (1011) away from the backplate gold (1012) is provided with a gold resonance layer structure frame (1014); The backplate gold (1012) side is attached to a piezoelectric displacement table to fix the silicon wafer layer (102), the position of the metasurface layer (101) is changed through the piezoelectric displacement table, and the longitudinal distance between the silicon wafer layer (102) and the metasurface layer (101) is moved.

2. The dynamically tunable, micromechanical-based beam deflection device of claim 1, wherein, The beam deflection components (1) are arranged in a matrix, and the resonance phases of the beam deflection components (1) in the direction of the incident wave electric field change in a linear gradient.

3. The dynamically tunable, micro-mechanical based beam deflection device of claim 2, wherein, The gold resonance layer structure frame (1014) and the backplate gold (1012) are both lossy metal layers, and the thicknesses of the gold resonance layer structure frame (1014) and the backplate gold (1012) are both 0.2 microns.

4. The dynamically tunable, micro-mechanical based beam deflection device of claim 3, wherein, The silicon wafer layer (102) is a high-resistance silicon wafer, and the thickness of the silicon wafer layer (102) is 50 microns.

5. Method for producing a micromechanical, dynamically adjustable beam deflection device for implementing the micromechanical, dynamically adjustable beam deflection device according to any one of claims 1 to 4, characterized in that The preparation method comprises: The silicon substrate is cleaned, and after cleaning, a backplate gold thin film is grown on the surface of the silicon substrate by a magnetron sputtering method; A polyimide thin film is spin-coated on the backplate gold thin film, and the backplate gold thin film after spin-coating the polyimide thin film is placed at a preset temperature for drying; After drying, the polyimide thin film is spin-coated with photoresist and dried to obtain a sample after spin-coating photoresist, and the sample is aligned and exposed with a mask by using a photoetching machine, developed by a positive photoresist developer after exposure, and the photoetching development effect is observed under a microscope; After growing a periodic metal structure on the surface of the sample by a magnetron sputtering method, the sample is placed in an N-methyl solution for static soaking, the non-structure gold thin film layer on the surface of the sample is removed by a plastic dropper, and the surface of the sample is sequentially cleaned with acetone, ethanol and water to obtain a metasurface layer; The silicon wafer layer is placed on a support plate and aligned with the metasurface layer mounted on the piezoelectric displacement table, so that the terahertz beam penetrates the silicon wafer layer and the support plate in sequence to irradiate the metasurface layer to obtain a beam deflection device.

6. The method of claim 5, wherein the micro-mechanical based dynamically tunable beam deflection device is prepared by a method comprising: The preset temperature for drying the backplate gold thin film after spin-coating the polyimide thin film comprises a first stage temperature, a second stage temperature, a third stage temperature and a fourth stage temperature: ​ The first stage temperature comprises: heating from room temperature to 80℃, the heating time is 20min, and maintaining at 80℃ for 30min; The second stage temperature comprises: heating from 80℃ to 140℃, the heating time is 15min, and maintaining at 140℃ for 30min; The third stage temperature comprises: heating from 140℃ to 200℃, the heating time is 15min, and maintaining at 200℃ for 30min; The third stage temperature comprises: increasing from 140 DEG C to 250 DEG C, the increasing time is 25 minutes, and maintaining at 250 DEG C for 30 minutes; The fourth stage temperature comprises: increasing from 250 DEG C to 320 DEG C, and maintaining at 320 DEG C for 2 hours.

7. The method of claim 6, wherein the micro-mechanical based dynamically tunable beam deflection device is formed by a process comprising: The thickness of the polyimide film in the polyimide film spin-coated on the back plate gold film is 10 microns. ​

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