Raman testing device and method for phase change material

Abstract

The invention provides a Raman testing device and method for a phase change material, and relates to the technical field of photon neuromorphic calculation. The Raman test device comprises a laser system used for emitting excitation light at a first moment to enable the phase change material to generate phase change, and emitting excitation light at a second moment to excite the phase change material to generate Raman signals, and the light intensity of the excitation light is greater than that of the excitation light; and the detection system is used for acquiring the Raman signal so as to determine the phase change degree of the phase change material. According to the Raman testing device, the phase change degree can be fed back in real time through the Raman signal in the phase change process, and in-situ material property detection is achieved under the condition that laser direct writing is not affected.

Description

Technical Field

[0001] The present application relates to the field of photonic neuromorphic computing technology, and in particular to a Raman testing device and method for phase change materials. Background Art

[0002] Photonic neuromorphic computing technology is a technology for processing neuromorphic computing data in the optical domain. It can fully utilize the advantages of photon high-speed transmission, low power consumption, and high parallelism, and can avoid the extra time and power consumption overhead caused by photoelectric and electro-optical conversion. It has great research and application value. In this field, phase-change materials (PCMs), as an optical material with high refractive index contrast and non-volatile properties, can continuously adjust the refractive index under the stimulation of light, electricity, heat, etc., providing a feasible solution for non-volatile photonic neuromorphic computing and becoming a current research hotspot.

[0003] The characteristic of phase change materials is that they have dynamically adjustable optical, electrical, magnetic and other physical properties. This is because the phase change material can produce changes in the lattice state under external stimulation, usually between the amorphous state and the crystalline state. The two states have completely different physical properties, so they can provide contrast states that can be distinguished in the logical state. When the phase change material is stimulated by external electricity, light, heat, etc., its lattice structure can switch between the amorphous state (completely disordered) and the crystalline state (completely ordered), showing obvious differences in external characteristics such as refractive index and resistivity. Taking GST material as an example, when it is in the amorphous state, the lattice structure is in a completely disordered state, and the optical refractive index, extinction coefficient, and electrical conductivity are relatively low. When it is in the crystalline state, the lattice structure is in a completely ordered state, and the optical refractive index, extinction coefficient, and electrical conductivity are relatively high. By using the difference between these two states, storage and computing applications can be designed and implemented.

[0004] Laser direct writing technology is a technology that focuses a laser beam into a very small light spot and acts on photosensitive or heat-sensitive thin film materials to change the properties of the thin film materials. Pulsed light is used to stimulate phase change materials to achieve reconfiguration between amorphous and crystalline states. When a crystalline phase change material is stimulated by a short and high pulse, the internal structure of the material is disrupted by the high-energy pulse and is converted into an amorphous state during rapid cooling. When an amorphous phase change material is stimulated by a long and low pulse, the material is melted, and the lattice is arranged in an orderly manner to re-form a crystalline state during the slow cooling process.

[0005] There are two most commonly used methods for characterizing the phase change state of phase change materials: one is X-ray diffraction (XRD), which determines the degree of phase change by the X-rays of the phase change material. When the crystal sample is irradiated with X-rays, since the wavelength of the X-rays is of the same order of magnitude as the atomic spacing of the crystal, a strong diffraction phenomenon can be generated in the direction of the crystal plane that satisfies the Bragg formula. The characteristics of the lattice structure inside the crystal can be reflected by analyzing the distribution of the diffraction intensity; the other is to obtain the optical constants under different phase change states. The optical constants of thin film materials can usually be obtained by two methods: one is to use an ellipsometer to calculate the optical constants by measuring the changes in the polarization state when polarized light is reflected or transmitted on the film; the other is to measure the reflectivity and transmittance. If the film thickness is known, the optical constants can be calculated by fitting the reflection spectrum or the transmission spectrum.

[0006] However, the above two methods are complicated to operate and require multiple steps of data processing to obtain results. They are not easy to operate and it is difficult to determine the degree of phase change in time during the phase change process of the phase change material. Summary of the invention

[0007] In order to solve at least one of the above problems, the present application proposes a Raman testing device and method for phase change materials.

[0008] According to the first aspect of the present application, at least one embodiment of the present application provides a Raman testing device for phase change materials, comprising: a laser system, configured to emit excitation light at a first moment to cause the phase change material to undergo a phase change, and to emit excitation light at a second moment to excite the phase change material to produce a Raman signal, wherein the light intensity of the excitation light is greater than the light intensity of the excitation light; and a detection system, configured to acquire the Raman signal to determine the degree of phase change of the phase change material.

[0009] For example, in some embodiments of the present application, the laser system includes: a laser direct writing unit, used to emit the excitation light at the first moment, and to emit the excitation light at the second moment; a first spectrometer, used to reflect the excitation light and the excitation light; an objective lens, used to receive the excitation light and the excitation light so as to be vertically incident on the phase change material, so as to cause the phase change material to undergo a phase change and excite the phase change material to produce a Raman signal.

[0010] For example, in some embodiments of the present application, the laser system includes: a laser direct writing unit, used to emit the excitation light at the first moment; a laser, used to emit the excitation light at the second moment; a laser collimator, used to modulate the excitation light into parallel light; a second beam splitter, used to reflect the parallel light; a first beam splitter, used to reflect the excitation light and the parallel light reflected by the second beam splitter; an objective lens, used to receive the excitation light and the parallel light reflected by the first beam splitter, so as to vertically incident on the phase change material, so as to cause the phase change material to undergo a phase change and excite the phase change material to generate a Raman signal, wherein the excitation light and the excitation light overlap on the phase change material.

[0011] For example, in some embodiments of the present application, the detection system includes: a filter for filtering the excitation light and the stimulation light reflected by the phase change material to allow the Raman signal to pass through; a spectrometer for acquiring the Raman spectrum of the Raman signal to determine the phase change degree of the phase change material.

[0012] For example, in some embodiments of the present application, the detection system further includes: a first lens, used to focus the Raman signal filtered by the filter and emit it to the spectrometer.

[0013] For example, in some embodiments of the present application, the detection system also includes: a spatial filter, used to detect the Raman signal focused by the first lens and filter out optical noise, and the spatial filter includes: a pinhole aperture; a second lens, used to receive the Raman signal passing through the spatial filter and emit it to the spectrometer.

[0014] For example, in some embodiments of the present application, the detection system further includes: an optical fiber coupler, used to couple the Raman signal filtered by the filter, and transmit the Raman signal to the spectrometer.

[0015] For example, in some embodiments of the present application, it also includes: a sample stage, which is used to place the phase change material and move it according to a set time so that the excitation light and the stimulation light are irradiated on different positions of the phase change material.

[0016] For example, in some embodiments of the present application, it also includes: a galvanometer system, including: an X-axis galvanometer, used to receive adjustment instructions to change the X-axis position of the excitation light and the emission of the excitation light; a Y-axis galvanometer, used to receive adjustment instructions to change the Y-axis position of the excitation light and the emission of the excitation light; the objective lens, used to receive the excitation light and the excitation light after the X-axis and Y-axis positions are changed, so as to be vertically incident on the phase change material, so that the excitation light and the excitation light are irradiated at different positions of the phase change material.

[0017] According to the second aspect of the present application, at least one embodiment of the present application provides a Raman testing method for phase change materials, which is performed by a Raman testing device as described in any one of the first aspects, and the Raman testing method includes: emitting excitation light at a first moment to cause the phase change material to undergo a phase change; emitting excitation light at a second moment to excite the phase change material to generate a Raman signal; and acquiring the Raman signal to determine the degree of phase change of the phase change material.

[0018] For example, in some embodiments of the present application, it also includes: moving the position of the phase change material, or using a galvanometer system to move the excitation light and the excitation light, so that the excitation light and the excitation light are irradiated on different positions of the phase change material.

[0019] Through the above-mentioned example embodiments, the present application provides a Raman testing device and method for phase change materials, which can provide real-time feedback on the degree of phase change through Raman signals during the phase change process, realize in-situ material property detection without affecting laser direct writing, and detect the degree of phase change in real time during the phase change excitation of the phase change material. The operation is simple, the feedback is real-time, and the results can be intuitively fed back through spectral comparison. It has strong operability and is a fast and non-destructive material characterization method with high spectral resolution and spatial resolution.

[0020] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] By describing in detail exemplary embodiments thereof with reference to the accompanying drawings, the above and other objects, features and advantages of the present application will become more apparent. The accompanying drawings described below are only some embodiments of the present application, and are not intended to limit the present application.

[0022] Figure 1 A schematic diagram of a Raman testing device for phase change materials according to an exemplary embodiment is shown;

[0023] Figure 2 A schematic diagram showing a direct writing point of a phase change material sample according to an exemplary embodiment;

[0024] Figure 3 Another embodiment of an exemplary Raman testing device is shown;

[0025] Figure 4 Another embodiment of an exemplary Raman testing device is shown;

[0026] Figure 5 Another embodiment of an exemplary Raman testing device is shown;

[0027] Figure 6 A schematic diagram showing a Raman testing method according to an exemplary embodiment;

[0028] Figure 7 A schematic diagram showing the timing of outputting excitation light and triggering light by a Raman testing device according to an exemplary embodiment;

[0029] Figure 8 A flow chart illustrating a phase change testing process of an exemplary embodiment is shown. DETAILED DESCRIPTION

[0030] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and will fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted.

[0031] The described features, structures or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced without one or more of these specific details, or other modes, components, materials, devices, etc. may be adopted. In these cases, known structures, methods, devices, implementations, materials or operations will not be shown or described in detail.

[0032] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0033] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0034] Those skilled in the art will appreciate that the drawings are merely schematic diagrams of example embodiments, and the modules or processes in the drawings are not necessarily necessary for implementing the present application, and therefore cannot be used to limit the scope of protection of the present application.

[0035] Figure 1A schematic diagram of a Raman testing device for phase change materials according to an exemplary embodiment is shown.

[0036] like Figure 1 As shown, the Raman testing device includes: a laser system 10 and a detection system 20 .

[0037] The laser system 10 is used to emit excitation light at a first moment to make the phase change material produce a phase change, and emit excitation light at a second moment to excite the phase change material to produce a Raman signal. The intensity of the excitation light is much greater than the intensity of the excitation light.

[0038] The detection system 20 is used to obtain Raman signals to determine the phase change degree of the phase change material.

[0039] According to an example embodiment, the laser system 10 includes a laser direct writing unit 101 , a first beam splitter 102 , and an objective lens 103 .

[0040] The laser direct writing unit 101 is used to emit excitation light at a first moment and emit excitation light at a second moment. The first beam splitter 102 is used to reflect the excitation light and the excitation light. The objective lens 103 is used to receive the excitation light and the excitation light to vertically incident on the phase change material, so as to cause the phase change material to undergo a phase change and excite the phase change material to generate a Raman signal.

[0041] According to some embodiments, the first beam splitter 102 is used to realize the function of splitting the light beam into reflection and transmission, including but not limited to beam splitters such as various ratios, polarization, and non-polarization beam splitters, beam splitters, half-reflecting and half-mirror glasses, dichroic mirrors, and Wollaston prisms.

[0042] According to some embodiments, the objective lens 103 uses an infinite conjugate design objective lens, that is, after the light reflected by the sample enters the objective lens 103, it does not converge but remains a parallel light beam, so that the required optical elements can be arbitrarily inserted on the detection system side.

[0043] According to some embodiments, the objective lens 103 may also be a field lens. This application only takes this as an example, but is not limited to this.

[0044] The detection system 20 includes: a filter 201 and a spectrometer 202 .

[0045] The filter 201 is used to filter the excitation light and the exciting light reflected by the phase change material, so that the Raman signal can pass through. The spectrometer 202 is used to obtain the Raman spectrum of the Raman signal to determine the phase change degree of the phase change material.

[0046] Raman spectroscopy is a fast, non-destructive method with high temporal and spatial resolution to characterize and detect material properties. It can provide information on material structure, electronic structure, lattice vibration, etc., can identify components, determine material microstructure, study phase change, measure parameters, select imaging, etc., and has been widely used in physics, chemistry, biology, medicine, materials science, microelectronics and other multidisciplinary fields. The document "A New Family of Ultralow Loss Reversible Phase-ChangeMaterials for Photonic Integrated Circuits: Sb2S3 and Sb2Se3" proves that the position and half-height width of the Raman peak of phase change materials in different phase change states are significantly different, and the phase change state of the material can be determined by Raman spectroscopy. The present invention is a method for laser direct writing in-situ Raman test characterization of phase change materials, which can provide real-time feedback on the degree of phase change through Raman light during the phase change process.

[0047] According to some embodiments, the filter 201 is used to achieve the transmission of a specific wavelength band, and different types of components can be selected according to actual applications.

[0048] In the first embodiment, the detection system 20 further includes a first lens 203 . The first lens 203 is used to focus the Raman signal filtered by the filter 201 and emit it to the spectrometer 202 .

[0049] In the second embodiment, the detection system 20 further includes: a first lens 203 , a spatial filter 204 and a second lens 205 .

[0050] The first lens 203 is used to focus the Raman signal filtered by the focusing filter 201. The spatial filter 204 is used to detect the Raman signal focused by the first lens 203 and filter out the optical noise. The second lens 205 is used to receive the Raman signal passing through the spatial filter 204 and emit it to the spectrometer 202.

[0051] A spatial filter is placed in front of the spectrometer, and the spatial filter is conjugate with the laser focus of the Raman excitation light on the sample. Therefore, the light from the laser focus can be detected by the detector through the pinhole of the spatial filter 204, while the scattered light at other positions will be blocked by the pinhole. This can effectively suppress the background light noise, improve the signal-to-noise ratio, and facilitate the detection of relatively weak Raman signals.

[0052] According to some embodiments, the spatial filter 204 may be a pinhole aperture. This application only takes this as an example, but is not limited thereto.

[0053] In the third embodiment, the detection system 20 further includes: an optical fiber coupler. The optical fiber coupler is used to couple the Raman signal filtered by the filter 201 and transmit the Raman signal to the spectrometer 202 .

[0054] According to an example embodiment, the Raman testing apparatus further includes a sample stage 30 .

[0055] The sample stage 30 is used to place the phase change material and is moved according to a set time so that the excitation light and the stimulation light are irradiated on different positions of the phase change material.

[0056] The direct-write pattern of phase-change materials consists of a dot matrix, e.g. Figure 2 As shown in the figure, the excitation light ends irradiation on the direct writing point of the sample, and the Raman excitation light begins to irradiate the direct writing point. The detection system collects the Raman signal and enters the spectrometer to obtain the Raman spectrum information, thereby determining the phase change degree of the direct writing point. And the result of this phase change degree can be fed back to the laser system so that the laser system can adjust the parameters.

[0057] According to an exemplary embodiment, the laser system 10 includes a galvanometer system 107, such as Figure 3 shown.

[0058] The galvanometer system 107 includes an X-axis galvanometer 108 and a Y-axis galvanometer 109. Figure 4 shown.

[0059] The X-axis galvanometer 108 is used to receive adjustment instructions to change the X-axis position of the emission of the excitation light and the excitation light. The Y-axis galvanometer 109 is used to receive adjustment instructions to change the Y-axis position of the emission of the excitation light and the excitation light. The objective lens 103 is used to receive the excitation light and the excitation light after the X-axis and Y-axis positions are changed, so as to vertically incident on the phase change material, so that the excitation light and the excitation light are irradiated at different positions of the phase change material.

[0060] Figure 5 Yet another embodiment of an exemplary Raman testing apparatus is shown.

[0061] Figure 5 Raman test device and Figure 1 The structure of the Raman test device is basically similar, the only difference is that Figure 5 The laser system of the Raman testing device shown further includes a laser 104 .

[0062] According to an exemplary embodiment, the laser direct writing unit 101 is used to emit excitation light at a first moment. The laser 104 is used to emit excitation light at a second moment. The excitation light and the excitation light overlap on the phase change material. Moreover, the intensity of the excitation light is much greater than the intensity of the excitation light.

[0063] According to some embodiments, since two light sources are incident on the sample through an objective lens, according to the theoretical Rayleigh resolution of 0.61*λ / NA, it can be known that the spot size focused by the objective lens is related to the incident wavelength. Therefore, light with a shorter wavelength can be selected as the Raman excitation light, thereby ensuring that the excitation area of ​​the Raman excitation light is smaller than the excitation area of ​​the laser direct writing, that is, all Raman signals come from the phase change area.

[0064] Figure 5 The laser system of the Raman testing device shown further includes a laser collimator 105 and a second beam splitter 106 .

[0065] The laser collimator 105 is used to modulate the excitation light into parallel light. The second beam splitter 106 is used to reflect the parallel light to the first beam splitter 102 so that the objective lens 103 receives the parallel light and the parallel light is vertically incident on the phase change material.

[0066] The present application also proposes a Raman testing method for phase change materials, which is performed by the Raman testing device as described above.

[0067] like Figure 6 As shown, the Raman testing method includes: emitting excitation light at a first moment to cause a phase change in a phase change material; emitting excitation light at a second moment to excite the phase change material to generate a Raman signal; and acquiring the Raman signal to determine the phase change degree of the phase change material.

[0068] Furthermore, after completing the direct writing excitation and Raman spectrum test of a direct writing point, the position of the phase change material is moved, or the excitation light and the stimulation light are moved so that the excitation light and the stimulation light are irradiated on the next direct writing point of the phase change material, and the above method is repeated.

[0069] According to some embodiments, the Figure 4 The galvanometer system shown moves the excitation light and the stimulation light, but other methods can also be used to move the excitation light and the stimulation light.

[0070] The present application provides a Raman testing device and method for phase change materials. During the phase change process, the degree of phase change can be fed back in real time through Raman signals, and in-situ material property detection can be achieved without affecting laser direct writing. The degree of phase change can be detected in real time during the phase change excitation of the phase change material. The operation is simple, the feedback is real-time, and the results can be intuitively fed back through spectral comparison. The device and method have strong operability, are a fast and non-destructive material characterization method, and have high spectral resolution and spatial resolution.

[0071] like Figure 7 As shown, at the time t1-t2, the excitation light is emitted with a light intensity of I1. At the time t2-t3, the excitation light is emitted with a light intensity of I2. I1 is much greater than I2. After completing the direct writing excitation and Raman spectrum test of a direct writing point, the sample stage is moved to repeat the above operation for the next direct writing point.

[0072] The samples are 23nm thick Sb2Se3 thin films of phase change material on two SiO2 substrates. The initial states of the samples are: sample A is amorphous and sample B is crystalline. At this time, the Raman spectra of the two samples are tested. The intensity of the Raman excitation light is set to 190uW, which are Raman spectrum A and Raman spectrum B, respectively, as a comparison of the subsequent phase change degree. The phase change between the crystalline and amorphous states is regulated by a laser system. The light source wavelength of the laser system is a tunable continuous laser with a wavelength of 638nm. The excitation light source of this application selects a 532nm continuous light laser. The filter is a 640nm long-pass filter.

[0073] Figure 8 The specific operation process of the Raman test method is as follows: Figure 5 Take the Raman test device shown as an example: the operation procedures for sample A and sample B are similar.

[0074] For sample A:

[0075] Set the pulse mode of the laser system light source to 50ms, 19mW, and adjust the system focus so that the spot of the 532nm laser on the sample coincides with the spot of the 638nm laser on the sample.

[0076] Turn on the laser system, output an excitation light pulse, turn on the Raman excitation light, set the light intensity to 190uW, test the Raman spectrum, complete the test of a laser direct writing point, and continue testing according to the laser system. Perform a Raman test after each laser direct writing pulse, and compare the Raman spectrum obtained from the test with the Raman spectrum A to determine that each point of laser direct writing is crystalline.

[0077] For sample B:

[0078] Set the pulse mode of the laser system light source to 400ns, 35mW, and adjust the system focus so that the spot of the 532nm laser on the sample coincides with the spot of the 638nm laser on the sample.

[0079] Turn on the laser system, output an excitation light pulse, turn on the Raman excitation light, set the light intensity to 190uW, test the Raman spectrum, complete the test of a laser direct writing point, and continue testing according to the laser system. Perform a Raman test after each laser direct writing pulse, and compare the Raman spectrum obtained from the test with Raman spectrum B. It can be determined that each point of laser direct writing is amorphous.

[0080] According to some embodiments, the switch control of the laser system in the present application is for the purpose of controlling the light entering the objective lens, including but not limited to controlling the laser switch or an external optical switch.

[0081] It should be clearly understood that the present application describes how to form and use specific examples, but the present application is not limited to any details of these examples. On the contrary, based on the teaching of the content disclosed in the present application, these principles can be applied to many other embodiments.

[0082] In addition, it should be noted that the above figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present application, and are not intended to be limiting. It is easy to understand that the processes shown in the above figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0083] The exemplary embodiments of the present application are specifically shown and described above. It should be understood that the present application is not limited to the detailed structures, configurations or implementations described herein; on the contrary, the present application is intended to cover various modifications and equivalent configurations included within the objectives and scope of the appended claims.

Claims

1. A Raman testing device for phase change materials, characterized in that: include: A laser system, configured to emit excitation light at a first moment to cause the phase change material to undergo a phase change, and to emit excitation light at a second moment to excite the phase change material to produce a Raman signal, wherein the light intensity of the excitation light is greater than the light intensity of the excitation light; The detection system is used to obtain the Raman signal to determine the phase change degree of the phase change material.

2. The Raman testing device according to claim 1, characterized in that: The laser system comprises: a laser direct writing unit, configured to emit the excitation light at the first moment, and emit the excitation light at the second moment; A first beam splitter, used for reflecting the excitation light and the stimulation light; The objective lens is used to receive the excitation light and the stimulation light to vertically impinge on the phase change material, so as to make the phase change material produce a phase change and stimulate the phase change material to produce a Raman signal.

3. The Raman testing device according to claim 1, characterized in that: The laser system comprises: A laser direct writing unit, configured to emit the excitation light at the first moment; a laser, configured to emit the excitation light at the second moment; A laser collimator, used for modulating the excitation light into parallel light; A second beam splitter, used for reflecting the parallel light; A first beam splitter, used for reflecting the excitation light and the parallel light reflected by the second beam splitter; The objective lens is used to receive the excitation light and the parallel light reflected by the first beam splitter to vertically incident on the phase change material, so as to cause the phase change material to undergo phase change and excite the phase change material to generate a Raman signal, wherein the excitation light and the parallel light overlap on the phase change material.

4. The Raman testing device according to claim 1, characterized in that: The detection system comprises: A filter, used for filtering the excitation light and the stimulation light reflected by the phase change material, so that the Raman signal can pass through; A spectrometer is used to obtain a Raman spectrum of the Raman signal to determine the phase change degree of the phase change material.

5. The Raman testing device according to claim 4, characterized in that: The detection system also includes: The first lens is used to focus the Raman signal filtered by the filter and emit it to the spectrometer.

6. The Raman testing device according to claim 5, characterized in that: The detection system also includes: A spatial filter, used to detect the Raman signal focused by the first lens and filter out optical noise, the spatial filter comprising: a pinhole diaphragm; The second lens is used to receive the Raman signal passing through the spatial filter and emit it to the spectrometer.

7. The Raman testing device according to claim 4, characterized in that: The detection system also includes: The optical fiber coupler is used to couple the Raman signal filtered by the filter and transmit the Raman signal to the spectrometer.

8. The Raman testing device according to claim 1, characterized in that: Also includes: The sample stage is used to place the phase change material and move according to a set time so that the excitation light and the stimulation light are irradiated on different positions of the phase change material.

9. The Raman testing device according to claim 2, characterized in that: The laser system further comprises: Galvanometer system, including: An X-axis galvanometer, used for receiving an adjustment instruction to change the X-axis position of the excitation light and the emission of the excitation light; A Y-axis galvanometer, used to receive an adjustment instruction to change the Y-axis position of the excitation light and the emission of the excitation light; The objective lens is used to receive the excitation light and the exciting light after changing the X-axis and Y-axis positions, so as to vertically incident on the phase change material, so that the excitation light and the exciting light are irradiated on different positions of the phase change material.

10. A Raman testing method for phase change materials, characterized in that: The Raman testing method is performed by the Raman testing device according to any one of claims 1 to 9, and comprises: emitting excitation light at a first moment to cause the phase change material to undergo a phase change; emitting excitation light at a second moment to excite the phase change material to generate a Raman signal; The Raman signal is acquired to determine the phase change degree of the phase change material.

11. The Raman testing method according to claim 10, characterized in that: Also includes: The position of the phase change material is moved, or the excitation light and the excitation light are moved using a galvanometer system, so that the excitation light and the excitation light are irradiated on different positions of the phase change material.

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