A chipized in-situ on-chip excitation platform

Abstract

The application aims at solving the technical problems that the prior art is difficult to realize the coupling and regulation of multiple physical fields such as heat, electricity, light, strain or ion migration in the chip scale, and is difficult to support the rapid switching and multiplexing of different in-situ modes in the same experimental system, and provides a chip in-situ on-chip excitation platform; comprising an insulating and heat-insulating support seat, a navigation plug connector installed on one side of the insulating and heat-insulating support seat, a chip seat installed on the insulating and heat-insulating support seat, a plurality of MEMS chip mounting windows are opened on the chip seat for carrying MEMS chips integrated with different on-chip excitation units, the on-chip excitation unit comprises one or more of a high-temperature excitation unit, an electrical excitation unit, a light-triggered ultrafast electric pulse excitation unit and a controllable interlayer excitation unit, and the chip seat is provided with an elastic pressure needle electrode for electrically connecting the MEMS chip and the navigation plug connector; the application can improve the compatibility and reusability of the in-situ on-chip excitation platform.

Description

Technical Field

[0001] This invention relates to an in-situ excitation platform, specifically to a chip-based in-situ on-chip excitation platform. Background Technology

[0002] Ultrafast electron diffraction devices and ultrafast electron microscopes are key in-situ characterization techniques for achieving femtosecond to picosecond time-atomic spatial resolution and accurately analyzing the microscopic ultrafast dynamic behavior of matter. They are of great significance to cutting-edge scientific fields such as next-generation information technology, quantum science and technology, high-temperature superconductivity, and topological quantum materials. These instruments not only rely on ultrafast electron probes with high spatiotemporal resolution but also urgently require various in-situ excitation methods that can simulate the actual service conditions of materials. Currently, in-situ characterization techniques have achieved various stimuli such as heating, bias voltage, strain, and gas / liquid environments. Typical related technologies are as follows:

[0003] Reference 1 (Sood A, Shen XZ, Shi Y, et al. Universal phase dynamics in VO2switches revealed by ultrafast operando diffraction. Science. 2021, 373, 352-355.) discloses an in-situ dynamics study method for electrically driven VO2 devices based on stroboscopic ultrafast electron diffraction. The insulator-metal phase transition is triggered by a step / square wave voltage pulse synchronized with the 180Hz clock of the ultrafast electron diffraction system, and the time-resolved measurement of structural evolution is achieved by electron pulse transmission diffraction with an electron pulse of about 100fs. At the same time, the device resistance / transport response is recorded synchronously with a high-speed oscilloscope to complete the precise correlation analysis between structural evolution and electrical switching process.

[0004] Reference 2 (Wang YB, Hossain MS, Li TL, et al. Ultrafast dynamics offerroelectric polarization of NbOI2 captured with femtosecond electrondiffraction. Nat Commun. 2025, 16, 8132.) discloses an in-situ method for studying the transient polarization dynamics of photoexcited ferroelectric materials using ultrafast electron diffraction. Taking NbOI2 nanocrystals as the research object, the sample was photoexcited by femtosecond laser pulses, and the ultrafast evolution process of crystal structure and polarization-related distortion after photoexcitation was detected in real time by ultrafast electron pulses, revealing the dynamic response mechanism of ferroelectric polarization in the sub-picosecond to picosecond timescale.

[0005] Reference 3 (Wu JB, Shan H, Chen WL, et al. In Situ Environmental TEM in Imaging Gas and Liquid Phase Chemical Reactions for Materials Research. Advanced Materials. 2016, 28: 9686–9712.) discloses an in-situ atmospheric transmission electron microscopy technique for in-situ observation of gas-solid reactions in an environmental transmission electron microscope. By using differential pumping or a windowed gas cell, a working atmosphere with controllable pressure and composition is formed in the sample area. Combined with an integrated heating element, in-situ imaging and diffraction characterization of materials such as catalysts are achieved in a high-temperature, reactive gas environment, thereby resolving the structural evolution and phase transition behavior of nanocatalytic particles under actual reaction conditions.

[0006] While the aforementioned technologies have made some progress, they share the following common problems: First, they focus on a single excitation method, making it difficult to achieve the coupling and control of multiple physical fields such as heat, electricity, light, strain, or ion migration at the chip scale, and thus unable to simulate the actual state of materials or devices under complex operating conditions. Second, they are customized around specific material systems and experimental objectives, lacking efficient integration between sample structures, excitation methods, and characterization platforms. A universal on-chip in-situ excitation architecture with uniform dimensions and interface specifications has not been formed, making it difficult to support rapid switching and reuse of different in-situ modes within the same experimental system. Summary of the Invention

[0007] The purpose of this invention is to solve the technical problems of existing technologies that make it difficult to achieve coupling and control of multiple physical fields such as heat, electricity, light, strain and ion migration at the chip scale, cannot simulate the actual state of materials or devices under complex working conditions, and cannot support the rapid switching and reuse of different in-situ modes in the same experimental system. Therefore, this invention provides a chip-based in-situ on-chip excitation platform.

[0008] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0009] A chip-based in-situ on-chip excitation platform includes an insulating and heat-insulating support base, an aviation connector mounted on one side of the insulating and heat-insulating support base for electrical connection with external devices, a chip mount mounted on the insulating and heat-insulating support base, and a MEMS chip and an on-chip excitation unit supported on the chip mount; its special feature is that:

[0010] The MEMS chip has an electron beam transparent window area for holding the sample to be characterized;

[0011] The on-chip excitation unit includes one or more of the following: high-temperature excitation unit, electrical excitation unit, optically triggered ultrafast electrical pulse excitation unit, and controllable intercalation excitation unit, and is integrated on the MEMS chip.

[0012] The chip socket has multiple MEMS chip mounting windows for supporting MEMS chips with different on-chip excitation units. Elastic pressure pin electrodes are located on one side of the MEMS chip mounting windows on the chip socket. Each elastic pressure pin electrode corresponds to a port electrode of the MEMS chip, and its contact end forms a point contact with the port electrode of the MEMS chip for conduction. The wiring end is led out through a wiring circuit located inside the insulating and heat-insulating support and the chip socket, and is electrically connected to the aviation connector. A screw clamping structure is located on the side of the chip socket away from the MEMS chip mounting windows on the side where the elastic pressure pin electrodes are located. A controllable clamping force is applied to the MEMS chip through the elastic pressure pin electrodes, ensuring reliable electrical contact between the port electrode of the MEMS chip and the elastic pressure pin electrodes, and achieving mechanical fixation of the MEMS chip.

[0013] The insulating and heat-insulating support base is also connected to a positioning pin for installing and limiting the platform on external equipment.

[0014] Furthermore, the MEMS chip is made of silicon-based substrate or gallium arsenide substrate and has an overall sheet structure. Multiple MEMS chips with the same external dimensions but different functions can be interchanged and installed.

[0015] Furthermore, the high-temperature excitation unit is a micro-nano heating resistor structure made of high-melting-point silicon carbide material;

[0016] The micro / nano heating resistor structure is serpentine or ring-shaped, and is arranged in a symmetrical wiring pattern around the transparent window area of ​​the electron beam;

[0017] The micro / nano heating resistor structure is electrically connected to the voltage port electrode and current port electrode of the MEMS chip via independent metal leads.

[0018] Furthermore, the electrical excitation unit is a micro / nano electrode structure and is electrically connected to the sample to be characterized. It is also electrically connected to the voltage loading electrode of the MEMS chip via an independent metal lead, and is used to apply a DC bias voltage, AC signal, or pulse electrical signal to the sample to be characterized.

[0019] Furthermore, the optically triggered ultrafast electrical pulse excitation unit includes a low-temperature gallium arsenide layer, a silicon dioxide layer, a ground wire, a signal line, and a photoconductive switch;

[0020] The MEMS chip is fabricated on a gallium arsenide substrate, with a low-temperature gallium arsenide layer and a silicon dioxide layer sequentially disposed on the gallium arsenide substrate from bottom to top. A through-hole is formed in the silicon dioxide layer at the corresponding position of the photoconductive switch to expose the underlying low-temperature gallium arsenide layer and provide an active area for triggering the photoconductive switch. A ground wire and a signal wire are disposed on the surface of the silicon dioxide layer and form a coplanar waveguide structure. The ground wire is electrically connected to the ground port electrode. One end of the signal wire is electrically connected to the signal port electrode for inputting a bias voltage, and the other end is electrically connected to the terminal matching electrode. The photoconductive switch is disposed at the end of the signal wire near the signal port electrode. The photoconductive switch uses an interdigitated electrode structure to form a photoconductive switch gap, which is used to improve optical triggering efficiency and reduce the trigger threshold. The sample to be characterized is disposed at the end near the terminal matching electrode, spaced apart from the photoconductive switch, and electrically connected to the signal wire.

[0021] Furthermore, the ultrafast electrical pulse excitation unit adopts an optical triggering method or an all-electrical excitation method;

[0022] The all-electric excitation method directly integrates radio frequency pulse circuits, nonlinear transmission lines, or frequency multiplier devices to achieve the generation and shaping of ultrafast electrical pulses.

[0023] Furthermore, the controllable intercalation excitation unit includes an intercalation ion source, an electrolyte, and an intercalation electrode;

[0024] The intercalation ion source is positioned opposite to the sample to be characterized, and the electrolyte is positioned between the intercalation ion source and the sample to be characterized, in order to form a local intercalation reaction region and realize ion transport.

[0025] The intercalated ion source is electrically connected to the high-end voltage loading electrode of the MEMS chip via an intercalated electrode and an independent metal lead; the sample to be characterized is electrically connected to the low-end voltage loading electrode of the MEMS chip via an intercalated electrode and an independent metal lead.

[0026] Furthermore, the electrolyte may be a liquid electrolyte, a solid electrolyte, a polymer electrolyte, a glassy electrolyte, or a gaseous reactant.

[0027] Furthermore, the electron beam transparent window region adopts a silicon nitride thin film structure.

[0028] Furthermore, the intercalation driving method of the controllable intercalation excitation unit adopts one or more mechanisms coupled from concentration gradient driving, chemical potential driving, and photo-induced driving, and its intercalation species is Li. + Na ＋ K ＋ Mg 2＋ H ＋ Or organic molecules.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] (1) The present invention provides a chip-based in-situ on-chip excitation platform, which can integrate one or more combinations of high temperature excitation units, electrical excitation units, optically triggered ultrafast electrical pulse excitation units and controllable intercalation excitation units onto a MEMS chip as required, so that the same platform has the ability to control multiple physical fields in-situ; at the same time, multiple MEMS chip mounting windows are set up, elastic pressure pin electrodes are used as contact elements, and a screw clamping structure is used to provide controllable clamping force to the MEMS chip placed in the MEMS chip mounting window, so that the port electrodes of the MEMS chip and the elastic pressure pin electrodes maintain stable pressure contact, and realize the rapid loading, unloading and interchange of MEMS chips, thereby improving the compatibility and reusability of the in-situ on-chip excitation platform of the present invention;

[0031] (2) The present invention achieves insulation isolation of the internal wiring circuit through the insulating and heat-insulating support base, while suppressing the heat diffusion generated by the MEMS chip excitation, reducing the risk of leakage and heat diffusion, and improving the thermal stability of the sample to be characterized and the long-term operational reliability of the in-situ on-chip excitation platform of the present invention.

[0032] (3) The MEMS chips with uniform external dimensions in the multiple MEMS chips of the present invention can be used with the assembly and lead-out architecture of “chip holder - MEMS chip mounting window - elastic pressure pin electrode - screw clamp fastening structure - aviation connector” to realize the interchangeable installation between MEMS chips with different functions. The platform is installed and limited by positioning pins to reduce assembly errors and position drift. This makes the in-situ on-chip excitation platform of the present invention easy to integrate into different ultrafast electron probe / ultrafast electron diffraction systems, improving the compatibility and reusability of the in-situ on-chip excitation platform to different systems. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the chip-based in-situ on-chip excitation platform of the present invention;

[0034] Figure 2 This is a schematic diagram of the structure of the first MEMS chip in an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the structure of the second MEMS chip in an embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the structure of the third MEMS chip in an embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram of the structure of the fourth MEMS chip in an embodiment of the present invention.

[0038] The attached figures are labeled as follows:

[0039] 1-Chip socket, 2-Elastic pressure pin electrode, 3-Screw clamping fastening structure, 4-MEMS chip mounting window, 5-Insulating and heat-insulating support, 6-Positioning pin, 7-Aircraft connector, 8-Silicon substrate, 9-Low-end current electrode, 10-Low-end voltage electrode, 11-Low-end voltage loading electrode, 12-High-end voltage loading electrode, 15-High-end voltage electrode, 16-High-end current electrode, 17-Independent metal lead, 19-Micro / nano heating resistor structure, 20-Micro / nano electrode structure, 21-Sample to be characterized, 22-Pump laser, 23-Detector electron beam, 24-Gallium arsenide substrate, 25-Low-temperature gallium arsenide layer, 26-Silicon dioxide layer, 27-Ground wire, 28-Signal line, 29-Ground port electrode, 30-Photoconductive switch, 31-Optical trigger laser, 32-Ultrafast electrical pulse signal, 33-Intercalation ion source, 34-Liquid electrolyte, 35-Intercalation electrode. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] As attached Figure 1 As shown, this embodiment provides a chip-based in-situ on-chip excitation platform, which consists of a chip mount 1 and an insulating and heat-insulating support 5. An aviation connector 7 is provided on one side of the insulating and heat-insulating support 5. The insulating and heat-insulating support 5 provides electrical insulation for its internal wiring circuitry, while reducing heat dissipation generated by chip excitation and improving the thermal stability of the sample to be characterized. The chip mount 1 has four MEMS chip mounting windows 4 for placing MEMS chips, two of which are eight-electrode chip mounting windows and the other two are six-electrode chip mounting windows. The eight-electrode and six-electrode chip mounting windows are of different sizes to accommodate MEMS chips of different sizes, while MEMS chips of the same size but different functions can be interchanged. Meanwhile, the chip mount 1... A flexible pressure pin electrode 2 is provided on one side of the MEMS chip mounting window 4. A screw clamping fastening structure 3 is provided on the chip holder 1 on the side of the flexible pressure pin electrode 2 away from the MEMS chip mounting window 4. The screw clamping fastening structure 3 applies a controllable clamping force to the MEMS chip, so that the port electrode of the MEMS chip and the flexible pressure pin electrode 2 form a reliable electrical contact and achieve mechanical fixation of the MEMS chip. The flexible pressure pin electrode 2 corresponds one-to-one with the port electrode of the MEMS chip. Its contact end is used to form point contact and conduction with the port electrode of the MEMS chip. The wiring end is led out through the wiring circuit provided in the insulating and heat-insulating support 5 and the chip holder 1 and is electrically connected to the aviation connector 7. The insulating and heat-insulating support 5 is also connected to the positioning pin 6 for installation and limiting.

[0042] Among them, the four MEMS chip mounting windows 4 respectively carry the first MEMS chip, the second MEMS chip, the third MEMS chip and the fourth MEMS chip. The first MEMS chip, the second MEMS chip, the third MEMS chip and the fourth MEMS chip have different functions due to the different composition structure of the on-chip excitation unit integrated on them.

[0043] like Figure 2 As shown, the first MEMS chip uses a silicon substrate 8 as its base. An electron beam transparent window is set on the top of the chip to carry the sample 21 to be characterized. The electron beam transparent window area adopts a silicon nitride thin film structure. The on-chip excitation unit carried on the first MEMS chip includes a high-temperature excitation unit and an electrical excitation unit. The high-temperature excitation unit is a micro-nano heating resistor structure 19 made of high-melting-point silicon carbide material. Its overall shape is serpentine and it is arranged in a symmetrical wiring manner around the electron beam transparent window area. It is also connected to the high-side current electrode 16, low-side current electrode 9, high-side voltage electrode 15 and low-side voltage electrode 16 of the first MEMS chip through independent metal leads 17. The system has an electrical connection to form an energized heating circuit and provide a temperature feedback signal. The electrical excitation unit is a micro / nano electrode structure 20, which is electrically connected to the sample 21 to be characterized, and is also electrically connected to the two low-end voltage loading electrodes 11 and the two high-end voltage loading electrodes 12 of the first MEMS chip through independent metal leads 17, respectively, to apply DC bias, AC signal or pulsed electrical signal to the sample. A laser beam emitted by an external laser is split into two paths by a beam splitter. One path is a pump laser 22, which serves as the optical excitation unit of the first MEMS chip, and the other path is used to trigger the electron gun to generate a probe electron beam 23 for ultrafast structural detection of the sample 21 to be characterized.

[0044] like Figure 3As shown, the second MEMS chip uses a silicon substrate 8 as its base. An electron beam transparent window is set on the top of the chip to carry the sample 21 to be characterized. The electron beam transparent window area adopts a silicon nitride thin film structure. The on-chip excitation unit carried on the second MEMS chip includes a high-temperature excitation unit and an electrical excitation unit. The high-temperature excitation unit is a micro-nano heating resistor structure 19 made of high-melting-point silicon carbide material. Its overall shape is serpentine and it is arranged in a symmetrical wiring manner around the electron beam transparent window area. It is also connected to the high-side current electrode 16, low-side current electrode 9, high-side voltage electrode 15 and low-side voltage electrode 16 of the second MEMS chip through independent metal leads 17. The first MEMS chip has an electrical connection to form an energized heating circuit and provide a temperature feedback signal. The electrical excitation unit is a micro / nano electrode structure 20, which is electrically connected to the sample 21 to be characterized, and is also electrically connected to a low-end voltage loading electrode 11 and a high-end voltage loading electrode 12 of the second MEMS chip through independent metal leads 17, respectively, to apply DC bias, AC signal or pulsed electrical signal to the sample. A laser beam emitted by an external laser is split into two paths by a beam splitter: one path is a pump laser 22, which serves as the optical excitation unit of the first MEMS chip, and the other path is used to trigger the electron gun to generate a probe electron beam 23 for ultrafast structural detection of the sample 21 to be characterized.

[0045] like Figure 4As shown, the third MEMS chip uses a gallium arsenide substrate 24, on which the on-chip excitation unit is a light-triggered ultrafast electrical pulse excitation unit. The light-triggered ultrafast electrical pulse excitation unit includes a low-temperature gallium arsenide layer 25, a silicon dioxide layer 26, a ground wire 27, a signal line 28, and a photoconductive switch 30. The low-temperature gallium arsenide layer 25 and the silicon dioxide layer 26 are sequentially disposed on the gallium arsenide substrate 24 from bottom to top. The silicon dioxide layer 26 has a through hole at the corresponding position of the photoconductive switch 30 to expose the underlying low-temperature gallium arsenide layer 25 and provide an active area for triggering the photoconductive switch 30. The ground wire 27 and the signal line 28 are disposed on the surface of the silicon dioxide layer 26 and form a coplanar waveguide structure. There are two ground wires 27 and four ground port electrodes 29. The two ends of the two ground wires 27 are electrically connected to the four ground port electrodes 29 respectively. The four ground port electrodes 29 are all electrically connected to the same external ground terminal to achieve a common ground connection. One end of the signal line 28 is electrically connected to the signal port electrode 12. One end is used to input the bias voltage, and the other end is electrically connected to the terminal matching electrode 11. The terminal matching electrode 11 is connected to the terminal load through an external circuit to achieve impedance matching. The photoconductive switch 30 is set at one end of the signal line 28 of the coplanar waveguide structure near the signal port electrode 12. The photoconductive switch 30 adopts an interdigitated electrode structure to form a photoconductive switch gap to improve the optical triggering efficiency and reduce the triggering threshold. The sample to be characterized is set at one end near the terminal matching electrode 11, spaced apart from the photoconductive switch 30, and electrically connected to the signal line 28. When the photo-triggered laser 31 irradiates the interdigitated photoconductive switch 30, under the action of the input bias voltage, the interdigitated photoconductive switch 30 instantaneously generates photogenerated carriers and undergoes a conductance change, thereby exciting the formation of an ultrafast electrical pulse signal 32. The ultrafast electrical pulse signal 32 is transmitted along the signal line 28 to the sample to be characterized, applying transient electrical excitation to the sample to be characterized. The probe electron beam 23 is used to perform ultrafast structure detection on the sample to be characterized 21.

[0046] like Figure 5 As shown, the fourth MEMS chip uses a silicon substrate 8 as its base, and the on-chip excitation units carried on it include a high-temperature excitation unit and a controllable intercalation excitation unit. The controllable intercalation excitation unit includes an intercalation ion source 33, a liquid electrolyte 34, and an intercalation electrode 35. The intercalation ion source 33 is positioned opposite to the sample 21 to be characterized, and the liquid electrolyte 34 is positioned between the intercalation ion source 33 and the sample 21 to be characterized, in order to form a local intercalation reaction region and realize ion transport. The intercalation ion source 33 is electrically connected to the high-side voltage loading electrode 12 of the MEMS chip in sequence through the intercalation electrode 35 and the independent metal lead 17. The sample 21 to be characterized is electrically connected to the low-side voltage loading electrode 11 of the MEMS chip in sequence through the intercalation electrode 35 and the independent metal lead 17 to realize bias loading and signal extraction. The high-temperature excitation unit is a micro-nano heating resistor structure 19, which is electrically connected to the low-side current electrode 9 and the high-side current electrode 16 in sequence through the independent metal lead 17.

[0047] Based on the above embodiments, and through multiple adjustments and experimental comparisons of the chip-based in-situ on-chip excitation platform structure by technical personnel, other preferred local replacement schemes have been obtained, including:

[0048] ①The substrate materials for the first MEMS chip, the second MEMS chip and the fourth MEMS chip can also be glass, quartz, sapphire and other substrates with good mechanical strength and thermal stability;

[0049] ② In addition to Si3N4, the transparent window region for the electron beam can also be made of SiO2, SiC, Al2O3, graphene, or other thin film materials with high strength, high electron transmittance, and good heat resistance. As long as the requirements for electron beam transmission, vacuum compatibility, and mechanical strength are met, on-chip excitation and detection functions similar to those of this invention can be achieved. The specific shape (circular, rectangular, cross-shaped, etc.) and size of the window can also be adjusted according to the electron beam size and field of view requirements.

[0050] ③ The optically triggered ultrafast electrical pulse excitation unit of the third MEMS chip can be replaced by an ultrafast electrical pulse generation structure that integrates radio frequency pulse circuits, nonlinear editing transmission lines or frequency doubling devices. As long as a high-bandwidth electrical pulse of 10ps can be generated on the third MEMS chip and effectively transmitted to the sample area to achieve time synchronization with the ultrafast electron probe, the specific waveform, amplitude and repetition frequency of the electrical pulse can be flexibly designed according to the target material system and experimental requirements.

[0051] ④ The electrolyte used in the fourth MEMS chip is not limited to liquid electrolyte 34, but can also be solid electrolyte, polymer electrolyte, glassy electrolyte, or gaseous reactant that can be intercalated under the action of electric field / chemical potential. The intercalation driving method of the controllable intercalation excitation unit adopts one or more of the following mechanisms coupled driving: concentration gradient driving, chemical potential driving, and photo-driven driving. The intercalation species is Li. + Na ＋ K ＋ Mg 2＋ H ＋ or organic molecules, etc.;

[0052] ⑤ The chip holder 1 can be adapted to different models of ultrafast electron diffraction or 4D ultrafast electron microscopy systems. Its mechanical interface can be a planar sample stage structure, a pluggable snap-fit ​​structure, or an adapter flange structure, etc.

[0053] Taking the aforementioned first MEMS chip as an example, based on the aforementioned chip-based in-situ on-chip excitation platform, the method for realizing multi-physics field coupled ultrafast electron diffraction characterization includes the following steps:

[0054] Step 1: Preparation and loading of sample 21 to be characterized

[0055] The sample 21 to be characterized is transferred to the electron beam transparent window area of ​​the first MEMS chip, so that the sample 21 to be characterized is covered by the electron beam transparent window area of ​​the silicon nitride thin film structure. At the same time, it is ensured that the sample 21 to be characterized forms a reliable electrical contact with the micro-nano electrode structure 20 on the first MEMS chip, so as to ensure that the subsequent electrical signal can be effectively loaded onto the sample 21 to be characterized.

[0056] Step 2: First MEMS chip installation and electrical connection

[0057] First, loosen the fastening screws of the screw clamping structure 3 located on the MEMS chip mounting window, so that the clamping structure of the screw clamping structure 3 is in a loose state; then, place the first MEMS chip loaded with the sample 21 to be characterized into the MEMS chip mounting window 4 of the chip-based in-situ on-chip excitation platform, so that the port electrode of the first MEMS chip is aligned with the elastic pressure needle electrode 2 provided on one side of the MEMS chip mounting window 4; finally, slowly tighten the fastening screws, and the clamping structure applies a controllable clamping force downward through the elastic pressure needle electrode 2, so that the first MEMS chip is stably fixed in the MEMS chip mounting window 4, and the port electrode of the first MEMS chip forms a stable crimp electrical contact with the elastic pressure needle electrode.

[0058] Step 3: Loading of the high-temperature excitation unit and the electrical excitation unit

[0059] First, the wiring circuit inside the platform is connected to the external power supply and signal control system through the aviation connector 7 set on the chip-based in-situ excitation platform. The aviation connector 7 is used to realize the stable transmission of multi-channel electrical signals, so that the external power supply can establish electrical connections with the high-end current electrode 16, the low-end current electrode 9, the high-end voltage electrode 15, the low-end voltage electrode 10, the high-end voltage loading electrode 12, and the low-end voltage loading electrode 11 respectively.

[0060] Subsequently, a driving current is applied to the high-end current electrode 16 and the low-end current electrode 9 by an external power source, causing the serpentine micro-nano heating resistor structure 19 made of silicon carbide to generate Joule heating, thereby heating the sample 21 to be characterized in the transparent window area of ​​the electron beam; at the same time, the voltage signal across the micro-nano heating resistor structure 19 is collected by the high-end voltage electrode 15 and the low-end voltage electrode 10, and temperature feedback and closed-loop control are realized based on its resistance change, so that the sample 21 to be characterized reaches the preset experimental temperature.

[0061] Finally, after the sample 21 to be characterized reaches the target temperature, the required electrical signals are applied to the micro-nano electrode structure 20 through two low-end voltage loading electrodes 11 and two high-end voltage loading electrodes 12 to apply DC bias, AC signal or pulse electrical signal to the sample 21 to achieve the control of the electrical state or carrier dynamics behavior of the sample 21.

[0062] Step 4: Optical pumping excitation

[0063] The sample 21 to be characterized is photoexcited by a pump laser 22 located in the transparent window region of the electron beam, thereby generating photogenerated carriers or triggering ultrafast physical processes such as structural phase transitions inside the sample 21.

[0064] Step 5: Ultrafast Electron Diffraction Detection

[0065] Under the set pump-probe time delay conditions, the sample 21 to be characterized is subjected to ultrafast electron diffraction measurement by using the probe electron beam 23 to penetrate the transparent window region of the electron beam. By recording the diffraction patterns under different time delays, the transient structural dynamics of the sample 21 to be characterized under multi-physics coupling conditions is realized.

[0066] Step 6: Data Collection and Analysis

[0067] By acquiring diffraction patterns using an electron detector and processing the data, the structural evolution information of the sample 21 to be characterized under multi-field coupling conditions such as temperature, electric field, and photoexcitation is obtained, thereby analyzing the ultrafast structural response and dynamic behavior of the material.

[0068] The above are merely embodiments of the present invention and are not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the technical solutions of the present invention should be included within the scope of protection of the present invention. Furthermore, it should be noted that the accompanying drawings are merely illustrative and are not drawn to scale, and should not be construed as limiting the actual scope of protection claimed by the present invention.

Claims

1. A chip-based in-situ on-chip excitation platform, comprising an insulating and heat-insulating support base (5), an aviation connector (7) mounted on one side of the insulating and heat-insulating support base (5) for electrical connection with external devices, a chip mount (1) mounted on the insulating and heat-insulating support base (5), and a MEMS chip and an on-chip excitation unit supported on the chip mount (1); characterized in that: The MEMS chip has an electron beam transparent window area for carrying the sample to be characterized (21). The on-chip excitation unit includes one or more of the following: high-temperature excitation unit, electrical excitation unit, optically triggered ultrafast electrical pulse excitation unit, and controllable intercalation excitation unit, and is integrated on the MEMS chip. The chip holder (1) has multiple MEMS chip mounting windows (4) for carrying MEMS chips with different on-chip excitation units. On one side of the MEMS chip mounting window (4), there is an elastic pressure pin electrode (2). The elastic pressure pin electrode (2) corresponds to the port electrode of the MEMS chip. Its contact end is used to form point contact with the port electrode of the MEMS chip. The wiring end is led out through the wiring circuit set in the insulating and heat-insulating support base (5) and the chip holder (1) and electrically connected to the aviation connector (7). On the side of the chip holder (1) away from the MEMS chip mounting window (4), there is a screw clamping fastening structure (3). The elastic pressure pin electrode (2) applies a controllable clamping force to the MEMS chip, so that the port electrode of the MEMS chip and the elastic pressure pin electrode (2) form a reliable electrical contact and realize the mechanical fixation of the MEMS chip. The insulating and heat-insulating support base (5) is also connected to a positioning pin (6) for installing and limiting the platform on external equipment.

2. The chip-based in-situ on-chip excitation platform according to claim 1, characterized in that: The MEMS chip is made of silicon substrate (8) or gallium arsenide substrate (24) and has a sheet structure. Multiple MEMS chips with the same external size but different functions can be interchanged and installed.

3. The chip-based in-situ on-chip excitation platform according to claim 1, characterized in that: The high-temperature excitation unit is a micro-nano heating resistance structure made of high-melting-point silicon carbide material (19). The micro / nano heating resistor structure (19) is serpentine or ring-shaped and is arranged in a symmetrical wiring manner around the transparent window area of ​​the electron beam; The micro / nano heating resistor structure (19) is electrically connected to the voltage port electrode and current port electrode of the MEMS chip via independent metal leads (17).

4. The chip-based in-situ on-chip excitation platform according to claim 1, characterized in that: The electrical excitation unit is a micro-nano electrode structure (20) and is electrically connected to the sample to be characterized (21). It is electrically connected to the voltage loading electrode of the MEMS chip through an independent metal lead (17) and is used to apply DC bias, AC signal or pulse electrical signal to the sample to be characterized (21).

5. The chip-based in-situ on-chip excitation platform according to claim 2, characterized in that: The optically triggered ultrafast electrical pulse excitation unit includes a low-temperature gallium arsenide layer (25), a silicon dioxide layer (26), a ground wire (27), a signal line (28), and a photoconductive switch (30). The MEMS chip is made of a gallium arsenide substrate (24), and a low-temperature gallium arsenide layer (25) and a silicon dioxide layer (26) are sequentially disposed on the gallium arsenide substrate (24) from bottom to top; wherein the silicon dioxide layer (26) has a through hole at the corresponding position of the photoconductive switch (30) to expose the underlying low-temperature gallium arsenide layer (25) and provide an active area for triggering the photoconductive switch (30); the ground wire (27) and the signal line (28) are disposed on the surface of the silicon dioxide layer (26) and form a coplanar waveguide structure, and the ground wire (27) is electrically connected to the ground port electrode (29); One end of the signal line (28) is electrically connected to the signal port electrode (12) for inputting bias voltage, and the other end is electrically connected to the terminal matching electrode (11). The photoconductive switch (30) is located at one end of the signal line (28) near the signal port electrode (12). The photoconductive switch (30) adopts an interdigitated electrode structure to form a photoconductive switch gap, which is used to improve the light triggering efficiency and reduce the triggering threshold. The sample to be characterized (21) is located at one end near the terminal matching electrode (11), spaced apart from the photoconductive switch (30), and electrically connected to the signal line (28).

6. The chip-based in-situ on-chip excitation platform according to claim 1, characterized in that: The ultrafast electrical pulse excitation unit adopts either optical triggering or all-electrical excitation. The all-electric excitation method directly integrates radio frequency pulse circuits, nonlinear transmission lines, or frequency multiplier devices to achieve the generation and shaping of ultrafast electrical pulses.

7. The chip-based in-situ on-chip excitation platform according to claim 1, characterized in that: The controllable intercalation excitation unit includes an intercalation ion source (33), an electrolyte, and an intercalation electrode (35). The intercalation ion source (33) is positioned opposite to the sample to be characterized (21), and the electrolyte is positioned between the intercalation ion source (33) and the sample to be characterized (21) to form a local intercalation reaction region and achieve ion transport. The intercalated ion source (33) is electrically connected to the high-end voltage loading electrode (12) of the MEMS chip via the intercalated electrode (35) and the independent metal lead (17); the sample to be characterized (21) is electrically connected to the low-end voltage loading electrode (11) of the MEMS chip via the intercalated electrode (35) and the independent metal lead (17).

8. The chip-based in-situ on-chip excitation platform according to claim 7, characterized in that: The electrolyte is a liquid electrolyte (34), a solid electrolyte, a polymer electrolyte, a glassy electrolyte, or a gaseous reactant.

9. The chip-based in-situ on-chip excitation platform according to claim 1, characterized in that: The electron beam transparent window region adopts a silicon nitride thin film structure.

10. The chip-based in-situ on-chip excitation platform according to claim 1, characterized in that: The controllable intercalation excitation unit employs a coupling of one or more mechanisms among concentration gradient driving, chemical potential driving, and photo-induced driving, with Li as the intercalation species. + Na ＋ K ＋ Mg 2＋ H ＋ Or organic molecules.

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