Non-contact temperature measurement device and method based on thin film material

Abstract

The application relates to a non-contact temperature measuring device and method based on a film material. The device comprises a steady-state laser for emitting a main light beam for temperature measurement; a light splitting component for splitting the main light beam into a reference light beam incident to a photoelectric detection component and a temperature measuring light beam incident to a film material covering the surface of a temperature measuring object; the film material reflects the temperature measuring light beam to form a temperature measuring reflected light beam which can be received by the photoelectric detection component; the photoelectric detection component calculates a temperature offset value of the current relative reference temperature of the film material based on the received reference light beam and the temperature measuring reflected light beam; and a surface temperature value of the temperature measuring object is generated based on the reference temperature and the temperature offset value. The application can effectively realize the temperature measurement of the surface of the temperature measuring object based on the film material in a non-contact state, and has high temperature measurement sensitivity and accuracy.

Description

Technical Field

[0001] This invention relates to a temperature measuring device and method, and more particularly to a non-contact temperature measuring device and method based on thin film materials. Background Technology

[0002] In fields such as semiconductor devices, optoelectronic devices, and energy materials, surface temperature measurement based on thin film materials is of great significance for device performance evaluation, reliability analysis, and thermal management optimization. However, traditional contact temperature measurement methods (such as thermocouples and resistance temperature detectors) suffer from low measurement accuracy, slow response speed, and susceptibility to interference with the temperature field of the measured object, making it difficult to meet the requirements for high-precision, high spatiotemporal resolution temperature measurement, especially in micro- and nano-scale thin film materials. Furthermore, the introduction of contact temperature measurement may damage the thin film structure or introduce additional thermal resistance, leading to distorted measurement results. Therefore, developing a non-contact, high-precision, and high-resolution method for measuring thin film surface temperature has become one of the key research challenges.

[0003] Non-contact temperature measurement technologies are mainly based on the principles of thermal radiation or changes in optical properties, such as infrared thermal imaging, Raman spectroscopy, and fluorescence thermometry. However, these methods still have many limitations in practical applications, specifically:

[0004] Infrared thermal imaging technology relies on the infrared radiation characteristics of the material being measured. However, the emissivity of thin film materials (especially ultrathin or transparent films) is often low or difficult to calibrate, limiting the accuracy of temperature measurement. Furthermore, the spatial resolution of infrared cameras is limited by the detector pixel size, making it difficult to achieve sub-micron level high-resolution temperature measurement.

[0005] Raman spectroscopy temperature measurement can retrieve temperature by analyzing the shift or intensity change of Raman peaks in a material. It has high spatial resolution (up to the micro-nano scale), but the signal intensity is weak, the measurement speed is slow, and it is sensitive to the crystal quality and optical properties of the material, making it difficult to apply to amorphous or multi-component compound thin films.

[0006] Fluorescence thermometry mainly utilizes the temperature-dependent luminescence characteristics of fluorescent materials. It requires doping the thin film with fluorescent probes, which may change the intrinsic properties of the material. Furthermore, the fluorescence signal is easily affected by environmental interference and has poor stability.

[0007] In recent years, the development of emerging technologies such as optical interferometry, time-domain thermal reflection (TDTR), or near-field thermal radiation has provided new ideas for thin film temperature measurement. However, these technologies are characterized by high equipment complexity, cumbersome data processing, or applicability only to specific material systems. Therefore, how to effectively achieve non-contact temperature measurement of thin film materials is a technical challenge that urgently needs to be addressed. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a non-contact temperature measurement device and method based on thin film materials, which can effectively realize the temperature measurement of the surface of the object to be measured in a non-contact state based on thin film materials, and has high temperature measurement sensitivity and accuracy.

[0009] According to the technical solution provided by the present invention, a non-contact temperature measuring device based on a thin film material is provided, the non-contact temperature measuring device comprising: A steady-state laser, used to emit the main beam for temperature measurement; The beam splitter is used to split the main beam into a reference beam incident on the photodetector and a temperature-measuring beam incident on the thin film material. The thin film material covers the surface of the object being measured; The thin film material reflects the temperature measuring beam and forms a temperature measuring reflected beam, which can be received by the photoelectric detection component; The photoelectric detection component calculates and generates the current temperature deviation of the thin film material relative to the reference temperature based on the received reference beam and the temperature-measuring reflected beam. The surface temperature value of the object being measured is generated based on the reference temperature and the temperature offset value.

[0010] The beam splitting assembly includes a beam splitter, a polarization controller positioned on the main beam path, and a reflector corresponding to the beam splitter. The main beam emitted by the steady-state laser is incident on a beam splitter via a polarization controller, which then splits the main beam into a reference beam and a temperature-measuring beam. The reference beam is incident on the photodetector via a reflector so that it can be received by the photodetector. The temperature-measuring beam is incident on the thin film material of the object being measured through the temperature-measuring optical path component, and the temperature-measuring reflected beam is incident on the photoelectric detection component through the temperature-measuring optical path component to be received by the photoelectric detection component.

[0011] The polarization controller is a polarizer or a half-wave plate.

[0012] The temperature-measuring optical path assembly includes a quarter-wave plate and a temperature-measuring objective lens disposed on the temperature-measuring beam path. During temperature measurement, the temperature measuring beam passes sequentially through a quarter-wave plate and a temperature measuring objective lens before being incident on the thin film material of the object being measured.

[0013] The frequency of the main beam is no greater than 1000Hz.

[0014] The thin film material is a metal, and its thickness is on the nanometer scale. When a steady-state laser emits its main beam, the wavelength of the main beam should correspond to the thermal reflectivity of the thin film material.

[0015] The photoelectric detection component includes a photodetector and a signal processor electrically connected to the photodetector, wherein... The reference beam and the temperature-reflected beam are received by a photodetector, and the beam differential signal is transmitted to the signal processor. The signal processor calculates and generates a temperature offset value of the thin film material relative to the reference temperature based on the signal amplitude of the beam differential signal. Subsequently, based on the reference temperature and the temperature offset value, it generates the surface temperature value of the object being measured.

[0016] Before temperature measurement, the following also applies: At the reference temperature, a steady-state laser is configured to emit the main beam, and a photodetector is used to receive the reference beam and the temperature-reflected beam to output the corresponding beam differential signal. Adjust the polarization controller until the amplitude of the beam differential signal is 0 to determine the temperature measurement status of the polarization controller.

[0017] The signal processor includes an oscilloscope or a lock-in amplifier.

[0018] A non-contact temperature measurement method based on thin film materials involves using the aforementioned non-contact temperature measurement device to measure the surface temperature of any object with a thin film material.

[0019] The advantages of this invention are as follows: A main beam is emitted by a steady-state laser, and a beam splitter divides the main beam into a reference beam and a temperature-measuring beam. The temperature-measuring beam is incident on the thin film material and reflected to form a temperature-measuring reflected beam. Both the temperature-measuring reflected beam and the reference beam are received by a photoelectric detection component, generating a beam differential signal. Based on the beam differential signal, a temperature offset value can be calculated. Based on the reference temperature and the temperature offset value, the surface temperature of the object being measured can be obtained. Throughout the temperature measurement process, there is no contact with the surface of the object being measured; therefore, it is non-contact and non-destructive, and it does not change the internal properties of the object being measured. Furthermore, by using corresponding beam forms for the reference beam and the temperature-measuring beam, the influence of laser noise can be effectively reduced, significantly improving the signal-to-noise ratio of the temperature measurement.

[0020] The steady-state laser emits a main beam with a spot size close to the submicron scale, enabling the measurement of temperature field distribution at the micron or even submicron scale. Compared to traditional technologies, this invention is based on the principle that the reflectivity of a thin film material to a specific wavelength of laser light is proportional to the temperature change. Since the thermal reflectivity of the thin film material is known (within 10...),... -5 K -1 Or 10 -4 K -1Therefore, after proper amplification, the change signal in thermal reflectivity can accurately and quickly detect minute temperature changes (such as 1 K). Since the film thickness of the thin film material is on the nanometer scale, the temperature of the thin film material is the surface temperature of the object being measured. Thus, the temperature measurement of this invention has a fast response capability, can improve the sensitivity and accuracy of temperature measurement, has universality, and can reduce the requirements for temperature measurement. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of one embodiment of the non-contact temperature measuring device of the present invention.

[0022] Figure 2 This is a schematic diagram of one embodiment of the signal processor of the present invention using an oscilloscope.

[0023] Figure 3 This is a schematic diagram of one embodiment of the signal processor of the present invention using a lock-in amplifier.

[0024] Explanation of reference numerals in the attached diagram: 1-Steady laser, 2-Main beam, 3-Polarization controller, 4-Beam splitter, 5-Reflector, 6-1 / 4 wave plate, 7-Temperature measuring beam, 8-Temperature measuring objective, 9-Temperature measuring object, 10-Reference beam, 11-Temperature measuring reflected beam, 12-Photodetector, 13-Signal processor, 14-Oscilloscope first channel, 15-Oscilloscope second channel, 16-Oscilloscope third channel, 17-Excitation signal channel, 18-Amplifier input port, 19-Amplifier reference signal port, 20-Oscilloscope, and 21-Lock-in amplifier. Detailed Implementation

[0025] The present invention will be further described below with reference to specific accompanying drawings and embodiments.

[0026] To effectively achieve non-contact temperature measurement of the surface of the object 9 based on a thin film material, this invention provides a non-contact temperature measurement device based on a thin film material. Specifically, the non-contact temperature measurement device includes: Steady-state laser 1, used to emit the main beam 2 for temperature measurement; The beam splitter is used to split the main beam 2 into a reference beam 10 incident on the photoelectric detection component and a temperature-measuring beam 7 incident on the thin film material. The thin film material covers the surface of the temperature measuring object 9; The thin film material reflects the temperature measuring beam 7 and forms a temperature measuring reflected beam 11, and the temperature measuring reflected beam 11 can be received by the photoelectric detection component. The photoelectric detection component calculates and generates the current temperature offset value of the thin film material relative to the reference temperature based on the received reference beam 10 and the temperature-measuring reflected beam 11. The surface temperature value of the temperature measuring object 9 is generated based on the reference temperature and the temperature offset value.

[0027] Figure 1 The figure illustrates an embodiment of the non-contact temperature measurement device of the present invention. As shown in the figure, to achieve non-contact temperature measurement, it should include a steady-state laser 1, which can emit a main beam 2. The steady-state laser 1 can be a commonly used laser, specifically designed to emit the main beam 2. To improve the reliability of non-contact temperature measurement, the frequency of the main beam 2 should not exceed 1000Hz. In specific implementation, the emission state of the steady-state laser 1 can be modulated, such as configuring the steady-state laser 1 to operate in a switching state, so that the steady-state laser 1 emits a main beam 2 in a square wave state. The specific method of modulating / configuring the operating state of the steady-state laser 1 can be consistent with the prior art, and will not be described in detail here.

[0028] During temperature measurement, the main beam 2 should be split using a beam splitter. After splitting, a reference beam 10 and a temperature measuring beam 7 can be generated. The reference beam 10 is generally received by a photoelectric detection component, while the temperature measuring beam 7 is incident on a thin film material. The thin film material should cover the surface of the object being measured. The material type of the thin film material is metal, and the thickness of the thin film material is in the nanometer range. The material type of the object being measured 9 can be metal, semiconductor, or dielectric material. In addition, the thin film material should reflect the laser beam and have a reflectivity of more than 95% so that after the temperature measuring reflected beam 7 is incident on the thin film material, the temperature measuring reflected beam 11 can be received by the photoelectric detection component.

[0029] It should be understood that when the surface of the object being measured 9 does not have the aforementioned thin film material, the required thin film material should first be applied to the surface of the object being measured 9. Conversely, when the surface of the object being measured 9 has the corresponding thin film material, temperature measurement can be performed directly on the object being measured. When it is necessary to apply a thin film material to the surface of the object being measured 9, the commonly used technical means in this field can be adopted according to the type of thin film material to apply the thin film material to the object being measured 9, thereby achieving coverage of the surface of the object being measured 9. Specific application methods can be selected as needed and will not be elaborated here. It should be noted that... Figure 1 Only the case of the temperature measuring object 9 is shown; the case where the thin film material covers the surface of the temperature measuring object 9 is not shown. In addition, when the steady-state laser 1 emits the main beam 2, the wavelength of the main beam 2 should correspond to the thermal reflectivity (dR / dT) of the thin film material. For example, the wavelength of the main beam 2 should be selected at the wavelength where the thermal reflectivity of the thin film material is relatively high.

[0030] After receiving the reference beam 10 and the temperature-measuring reflected beam 11, the photoelectric detection component can calculate the temperature deviation of the thin film material relative to the reference temperature. Then, based on the reference temperature and the temperature deviation, the surface temperature of the object being measured 9 can be obtained. Specifically, the temperature deviation can be positive or negative. Adding the temperature deviation to the reference temperature yields a temperature value characterizing the current temperature state of the thin film material. Because the thin film material is relatively thin, the obtained temperature value characterizes the surface temperature of the object being measured 9.

[0031] In one embodiment of the present invention, the beam splitting assembly includes a beam splitter 4, a polarization controller 3 disposed on the optical path of the main beam 2, and a reflector 5 corresponding to the beam splitter 4, wherein, The main beam 2 emitted by the steady-state laser 1 is incident on the beam splitter 4 via the polarization controller 3, so that the main beam 2 is split into the reference beam 10 and the temperature measuring beam 7 by the beam splitter 4. Reference beam 10 is incident on the photoelectric detection component via the reflector 5, so that it can be received by the photoelectric detection component; The temperature measuring beam 7 is incident on the thin film material of the temperature measuring object 9 through the temperature measuring optical path component, and the temperature measuring reflected beam 11 is incident on the photoelectric detection component through the temperature measuring optical path component so that it can be received by the photoelectric detection component.

[0032] Figure 1 The diagram illustrates one embodiment of a beam splitting assembly. As shown, a polarization controller 3 is located between the steady-state laser 1 and the beam splitter 4. The beam splitter 4 enables beam splitting, while the polarization controller 3 controls the polarization of the main beam 2. In practice, the polarization controller 3 can be a polarizer or a half-wave plate. The reference beam 10, formed by the beam splitter 4, is reflected by the reflector 5 and then incident on the photodetector assembly. The temperature-measuring beam 7, formed by the beam splitter 4, is first incident on the thin film material via the temperature-measuring optical path assembly. The temperature-measuring reflected beam 11, formed by the reflection of the thin film material, propagates along the optical path of the temperature-measuring beam 7 and is incident on the photodetector assembly for reception.

[0033] In one embodiment of the present invention, the temperature-measuring optical path assembly includes a quarter-wave plate 6 and a temperature-measuring objective lens 8 disposed on the temperature-measuring beam optical path 7, wherein, During temperature measurement, the temperature measuring beam 7 passes sequentially through the quarter-wave plate 6 and the temperature measuring objective lens 8 before being incident on the thin film material of the object being measured 9.

[0034] Figure 1The diagram illustrates one embodiment of a temperature-measuring optical path assembly. The assembly may include a quarter-wave plate 6 and a temperature-measuring objective lens 8. The objective lens 8 focuses a temperature-measuring beam 7 onto the thin film material of the object being measured, 9. Furthermore, by adjusting the objective lens 8, the focusing of the temperature-measuring beam 7 onto the thin film material can achieve a spatial resolution of 1 μm, thereby enabling micrometer or sub-micrometer level spatial temperature scanning.

[0035] In one embodiment of the present invention, the photoelectric detection component includes a photodetector 12 and a signal processor 13 adapted to and electrically connected to the photodetector 12, wherein, The photodetector 12 receives the reference beam 10 and the temperature-measuring reflected beam 11, and transmits the beam differential signal to the signal processor 13. The signal processor 13 calculates and generates a temperature offset value of the thin film material relative to the reference temperature based on the signal amplitude of the beam differential signal. Subsequently, based on the reference temperature and the temperature offset value, it generates the surface temperature value of the temperature measuring object 9.

[0036] Figure 1 The diagram also shows a schematic representation of an embodiment of the photoelectric detection component. As shown, the photoelectric detection component may further include a photodetector 12 and a signal processor 13. The photodetector 12 converts optical signals into electrical signals. When simultaneously receiving a reference beam 10 and a temperature-measuring reflected beam 11, a beam differential signal is generated, wherein the beam differential signal is an electrical signal. After the beam differential signal is transmitted to the signal processor 13, the signal processor 13 can calculate the signal amplitude of the beam differential signal and calculate a temperature offset value based on the signal amplitude. Specifically, when calculating the temperature offset value, the signal amplitude can be multiplied by the reflectivity of the thin film material, and the result of the product is used as the temperature offset value.

[0037] It should be understood that a reference temperature should be set within the signal processor 13 so that the surface temperature value of the object being measured 9 can be calculated after the temperature offset value is calculated. In one embodiment of the present invention, before temperature measurement, the following steps are also included: At the reference temperature, a steady-state laser 1 is configured to emit a main beam, and a photodetector 12 is used to receive a reference beam 10 and a temperature-measuring reflected beam 11 to output a corresponding beam differential signal. Adjust the polarization controller 3 until the amplitude of the beam differential signal is 0, in order to determine the temperature measurement working state of the polarization controller 3.

[0038] In practical implementation, when configuring the reference temperature, a thin film material should be provided and placed on the reference substrate. The reference substrate can be of the same type as the object being measured (9) or a different object; preferably, the same object should be used. It is understood that, based on the characteristics of the object being measured (9) and the working environment, the reference temperature of the object being measured (9) in the corresponding scenario can be determined. For example, the reference temperature can be room temperature or other temperatures that meet the requirements of the working scenario. Examples of reference temperatures will not be provided here.

[0039] To minimize the impact of laser noise on the temperature measurement results, this invention configures the temperature measurement operating state of the polarization controller 3. For example, by adjusting the polarization controller 3 so that the amplitude of the beam differential signal is 0, the corresponding state of the polarization controller 3 is used as the temperature measurement operating state. Here, "signal amplitude 0" specifically includes a signal amplitude that is exactly 0 or close to 0; the specific state can be selected as needed and will not be elaborated here. It should be noted that the method and process of adjusting the polarization controller 3 to achieve a signal amplitude of 0 can be consistent with existing technologies; the specific adjustment method will not be detailed here.

[0040] In one embodiment of the present invention, the signal processor 13 includes an oscilloscope 20 or a lock-in amplifier 21. The type of signal processor 13 can be selected as needed, specifically to meet the above-mentioned calculation of temperature offset value and corresponding surface temperature.

[0041] Figure 2 The diagram illustrates one embodiment of the oscilloscope 20. When the oscilloscope 20 is included, its first channel 14 receives the electrical signal formed by converting the reference beam, its second channel 15 receives the electrical signal formed by converting the temperature-sensing reflected beam, and its third channel 16 receives the beam differential signal output by the photodetector 12. In this case, the oscilloscope 20 can simultaneously output the two electrical signals and the corresponding waveforms of the beam differential signal. The excitation signal channel 17 of the oscilloscope 20 is used to receive the modulation frequency signal of the main beam 10. By modulating the frequency signal, the accuracy of calculating the amplitude of the corresponding beam differential signal can be improved, thereby improving the accuracy of temperature measurement.

[0042] Figure 3 An embodiment of the lock-in amplifier 21 is shown. When the lock-in amplifier 21 is included, the amplifier input port 18 of the lock-in amplifier 21 receives the beam differential signal output by the photodetector 12, and receives the adjustment frequency signal through the amplifier reference signal port 19. The situation of the modulation frequency signal can be referred to the corresponding description above, and will not be repeated here.

[0043] Based on the above description, the present invention can also provide a non-contact temperature measurement method based on thin film materials, specifically, For any object 9 with a thin film material, the above-described non-contact temperature measuring device is used to perform temperature measurement to determine the surface temperature of the object 9.

[0044] Specifically, the method and process of non-contact temperature measurement of the object 9 can be referred to the above description, and will not be repeated here.

[0045] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the concept and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A non-contact temperature measuring device based on thin film materials, characterized in that, The non-contact temperature measurement device includes: A steady-state laser, used to emit the main beam for temperature measurement; The beam splitter is used to split the main beam into a reference beam incident on the photodetector and a temperature-measuring beam incident on the thin film material. The thin film material covers the surface of the object being measured; The thin film material reflects the temperature measuring beam and forms a temperature measuring reflected beam, which can be received by the photoelectric detection component; The photoelectric detection component calculates and generates the current temperature deviation of the thin film material relative to the reference temperature based on the received reference beam and the temperature-measuring reflected beam. The surface temperature value of the object being measured is generated based on the reference temperature and the temperature offset value.

2. The non-contact temperature measuring device based on thin film material according to claim 1, characterized in that: The beam splitting assembly includes a beam splitter, a polarization controller positioned on the main beam path, and a reflector corresponding to the beam splitter. The main beam emitted by the steady-state laser is incident on a beam splitter via a polarization controller, which then splits the main beam into a reference beam and a temperature-measuring beam. The reference beam is incident on the photodetector via a reflector so that it can be received by the photodetector. The temperature-measuring beam is incident on the thin film material of the object being measured through the temperature-measuring optical path component, and the temperature-measuring reflected beam is incident on the photoelectric detection component through the temperature-measuring optical path component to be received by the photoelectric detection component.

3. The non-contact temperature measuring device based on thin film material according to claim 2, characterized in that: The polarization controller is a polarizer or a half-wave plate.

4. The non-contact temperature measuring device based on thin film material according to claim 2, characterized in that: The temperature-measuring optical path assembly includes a quarter-wave plate and a temperature-measuring objective lens disposed on the temperature-measuring beam path. During temperature measurement, the temperature measuring beam passes sequentially through a quarter-wave plate and a temperature measuring objective lens before being incident on the thin film material of the object being measured.

5. The non-contact temperature measuring device based on thin film material according to claim 2, characterized in that: The frequency of the main beam is no greater than 1000Hz.

6. The non-contact temperature measuring device based on thin film material according to claim 1, characterized in that: The thin film material is a metal, and its thickness is on the nanometer scale. When a steady-state laser emits its main beam, the wavelength of the main beam should correspond to the thermal reflectivity of the thin film material.

7. The non-contact temperature measuring device based on thin film material according to any one of claims 2 to 6, characterized in that: The photoelectric detection component includes a photodetector and a signal processor electrically connected to the photodetector, wherein... The reference beam and the temperature-reflected beam are received by a photodetector, and the beam differential signal is transmitted to the signal processor. The signal processor calculates and generates a temperature offset value of the thin film material relative to the reference temperature based on the signal amplitude of the beam differential signal. Subsequently, based on the reference temperature and the temperature offset value, it generates the surface temperature value of the object being measured.

8. The non-contact temperature measuring device based on thin film material according to claim 7, characterized in that: Before temperature measurement, the following also applies: At the reference temperature, a steady-state laser is configured to emit the main beam, and a photodetector is used to receive the reference beam and the temperature-reflected beam to output the corresponding beam differential signal. Adjust the polarization controller until the amplitude of the beam differential signal is 0 to determine the temperature measurement status of the polarization controller.

9. The non-contact temperature measuring device based on thin film material according to claim 7, characterized in that: The signal processor includes an oscilloscope or a lock-in amplifier.

10. A non-contact temperature measurement method based on thin film materials, characterized in that, For any object with a thin film material, the non-contact temperature measuring device described in any one of claims 1 to 9 is used to perform a temperature measurement operation to determine the surface temperature of the object.

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