Microzone transient thermal field detection system and method

Abstract

The application provides a micro-transient temperature field detection system and method. The detection system comprises: a light source module adapted to emit laser light; a sensing module comprising a reference grating and an atomic force probe; a feedback control module connected to the atomic force probe in the sensing module, the feedback control module being adapted to obtain a surface topography scanning result of a sample to be measured after the atomic force probe scans the sample to be measured; and a data processing terminal configured to process temperature sensing information by a spectral inversion algorithm and combine the surface topography scanning result to obtain a temperature field distribution of the surface of the sample to be measured. The micro-transient temperature field detection system and method can improve the accuracy and speed of micro-transient temperature field detection, and the detection result has high spatial and temporal resolution.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the field of optical fiber sensing temperature measurement technology, and in particular to a micro-region transient temperature field detection system and method. BACKGROUND

[0002] In the development process of the semiconductor industry, Moore's Law predicts the development rule of the semiconductor industry for nearly 50 years. However, in recent years, with the development of semiconductor technology to the nanometer level, the heat dissipation problem of the chip makes Moore's Law no longer applicable. Because the chip runs at an extremely fast speed, the heat accumulation of each transistor is also extremely fast, and damage to the transistor caused by heat is prone to occur. At present, ways such as limiting the clock frequency of the processor, increasing the multi-core parallel processor, and finding new materials to replace silicon are adopted to avoid the limitation of chip heating on the performance improvement of the chip. However, the fundamental problem of chip heating has not been solved. To solve this problem, first of all, we need to know where the problem is. Therefore, a means of high speed and capable of detecting the temperature field of the micro-nano region is needed.

[0003] When the existing thermal sensing technology is applied to the micro-region temperature measurement of the semiconductor core device, the following difficulties exist: 1. The size of the thermocouple probe is generally greater than 1 μm, and the time resolution cannot reach the precision of detecting the heat accumulation process of the chip due to the limitation of the probe reading. In addition, since most thermocouples are metal materials, they will interfere with the normal operation of the chip when they come into contact with the chip type sample; 2. The 3ω method is generally suitable for the measurement of nanometer materials, which requires placing the nanometer material between two electrodes, and finally obtaining the voltage signal containing the thermal parameter information of the material with a frequency of 3ω by applying an alternating signal with a frequency of ω. Therefore, this measurement method is not suitable for the detection of local temperature of the chip; 3. The thermal sensitive electrical parameter method is used to measure a specific PN junction in the semiconductor device, and the measurement needs to be carried out when the chip is not in working condition; 4. The scanning thermal field microscope is a temperature measurement method based on atomic force feedback, and its main measurement component is completed by a probe. Therefore, the probe of the scanning thermal field microscope generally has a metal component, which may interfere with the normal operation of the chip; 5. The transient thermal reflection method requires a layer of metal to be plated on the surface of the sample to be measured, so it is impossible to ensure the integrity of the sample to be measured; 6. The Raman spectroscopy method needs to use a strong laser to excite the sample, which causes great damage to some samples. Moreover, when reaching a high temperature, the Raman signal of the material will have a large noise; 7. The infrared thermal imaging technology is a relatively mature thermal detection method, but the spatial resolution is limited by the diffraction limit of light; 8. The spatial resolution of the reflective type temperature measurement of the optical fiber terminated with the thermal sensitive reflectivity material depends on the size of the reflectivity material, and the current conditions cannot achieve micro-region temperature measurement. SUMMARY

[0004] The technical problem solved by the present application is to provide a micro-region transient temperature field detection system and method, which can improve the accuracy and speed of micro-region transient temperature field detection, and the detection result has high spatial resolution.

[0005] To solve the above technical problem, the present application provides a micro-region transient temperature field detection system, which comprises: a light source module adapted to emit laser light, forming a laser path in the extension direction of the emitted laser light; a sensing module comprising a reference grating and an atomic force probe, which are arranged in sequence on the laser path, wherein the atomic force probe is adapted to scan a sample to be measured, and the laser light passes through the reference grating and the atomic force probe in sequence on the laser path and reaches the sample to be measured to form a detection signal, which carries temperature sensing information of the sample to be measured; a feedback control module connected to the atomic force probe in the sensing module, which is adapted to obtain the detection signal of the sample to be measured after the atomic force probe scans the sample to be measured; a dispersive element arranged on the laser path, which is adapted to process the detection signal, and the dispersion value of the dispersive element is configured to meet the requirement value of mapping the frequency domain information of the detection signal to the time domain; and a data processing terminal configured to process the temperature sensing information by a spectral inversion algorithm, and combine the surface topography scanning result to obtain the temperature field distribution of the surface of the sample to be measured.

[0006] In an embodiment of the present application, the atomic force probe comprises: a fiber grating nanoprobe having a cladding and a core in sequence from outside to inside in the radial direction; and a tuning fork adhered to the outside of the cladding.

[0007] In an embodiment of the present application, the reference grating and the fiber grating nanoprobe are connected in series on the same core and wrapped by the same cladding.

[0008] In an embodiment of the present application, the fiber grating nanoprobe adopts a fiber Bragg grating, and the tip of the fiber grating nanoprobe is prepared by a preparation method of hydrofluoric acid corrosion.

[0009] In an embodiment of the present application, the reference grating adopts a fiber Bragg grating, and the reflection wavelength range of the reference grating and the reflection wavelength range of the fiber grating nanoprobe do not intersect and / or coincide.

[0010] In an embodiment of the present application, the feedback control module comprises a tuning fork feedback type atomic force control device connected to the tuning fork in the atomic force probe, which is adapted to drive the atomic force probe to move in three-dimensional space.

[0011] In an embodiment of the present application, a three-dimensional displacement platform is further included for carrying the sample to be measured, and the three-dimensional displacement platform is adapted to move in three-dimensional space to enable the atomic force probe to complete scanning of the sample to be measured.

[0012] In an embodiment of the present application, a circulator is further included, and the circulator has a first end, a second end and a third end, wherein,

[0013] The laser is first input to the circulator from the light source module through the first end and output to the reference grating through the second end.

[0014] When the laser forms the detection signal, the detection signal is input to the circulator through the second end and output through the third end.

[0015] In an embodiment of the present application, a photodetector and a data acquisition device are further included, and the dispersion element, the photodetector and the data acquisition device are arranged in sequence between the third end of the circulator and the data processing terminal, wherein the photodetector is adapted to convert the optical signal contained in the detection signal into an electrical signal, and after the electrical signal is transmitted to the data acquisition device, the data acquisition device is adapted to transmit the data to the data processing terminal after completing data acquisition of the electrical signal.

[0016] In an embodiment of the present application, a coupler and a spectrometer are further included, and the detection signal is first passed through the coupler and dispersed into a first detection signal and a second detection signal before reaching the dispersion element, wherein the first detection signal is transmitted to the spectrometer, and the second detection signal is transmitted to the dispersion element.

[0017] In an embodiment of the present application, the dispersion element includes a dispersion device composed of a mirror, a chirped grating, a dispersion compensation fiber, a grating pair and / or a single-mode fiber.

[0018] In an embodiment of the present application, the spectrum inversion algorithm includes an algorithm realized by the following way: obtaining initial temperature information through an original grating reflection spectrum; calculating an inversion grating reflection spectrum through a transfer matrix method, combining the initial temperature information to calculate an error function, and calculating a difference between an actual grating reflection spectrum including the detection signal and the inversion grating reflection spectrum according to the error function; judging a relationship between the difference and a preset error value, obtaining an inversion temperature field when the difference is less than or equal to the preset error value to obtain a temperature curve corresponding to the chip to be measured, otherwise iteratively through the spectrum inversion algorithm until the difference between the actual grating reflection spectrum and the inversion grating reflection spectrum is less than or equal to the preset error value, and finally obtaining the inversion temperature field to obtain the temperature curve.

[0019] To solve the above technical problems, another aspect of the present application also proposes a micro-transient temperature field detection method, which comprises the following steps: emitting laser light by a light source module; scanning a sample to be measured by an atomic force probe; making the laser light pass through a reference grating in a sensing module and the atomic force probe in turn and reach the sample to be measured to form a detection signal, the detection signal carrying temperature sensing information of the sample to be measured; and transmitting the detection signal to a data processing terminal after processing by a dispersive element, and processing the temperature sensing information by the data processing terminal according to a spectrum inversion algorithm, and combining the surface topography scanning result to obtain the temperature field distribution of the surface of the sample to be measured, wherein the dispersion value of the dispersive element is configured to meet the requirement value of mapping the frequency domain information of the detection signal to the time domain.

[0020] In an embodiment of the present application, the spectrum inversion algorithm method comprises the following steps: obtaining initial temperature information by an original grating reflectance spectrum; calculating an inversion grating reflectance spectrum by a transfer matrix method, combining the initial temperature information to calculate an error function, and calculating the difference between the actual grating reflectance spectrum of the detection signal and the inversion grating reflectance spectrum according to the error function; judging the relationship between the difference and a preset error value, when the difference is less than or equal to the preset error value, obtaining an inversion temperature field to obtain the temperature curve corresponding to the sample to be measured, otherwise, iteratively processing by the spectrum inversion algorithm until the difference between the actual grating reflectance spectrum and the inversion grating reflectance spectrum is less than or equal to the preset error value, and finally obtaining the inversion temperature field to obtain the temperature curve.

[0021] Compared with the prior art, the present application has the following advantages: the present application prepares a fiber grating into a conical probe, and combines a tuning fork feedback type atomic force control means to complete the approach of the probe to the sample surface and the scanning of the sample surface, simultaneously applies a time stretching-dispersion Fourier transform technology to complete the system of high-speed demodulation of optical signals; the micro-transient temperature field detection system and method of the present application can achieve a nanometer-level lateral spatial resolution based on the size of the tip of the atomic force probe, and can obtain a nanometer-level longitudinal spatial resolution along the grating axial direction by combining the obtained spectrum with the spectrum inversion algorithm. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings are included to provide a further understanding of the present application, and they are collected and constitute a part of the present application, which show the embodiments of the present application, and together with the present specification, play a role in explaining the principles of the present application. In the drawings:

[0023] Figure 1 is a system architecture diagram of a micro-transient temperature field detection system according to an embodiment of the present application;

[0024] Figure 2is an instrument arrangement framework diagram of a micro-transient temperature field detection system according to an embodiment of the present application;

[0025] Figure 3 is a flow diagram of a micro-transient temperature field detection method according to an embodiment of the present application; and

[0026] Figure 4 is an experimental effect diagram of a micro-transient temperature field detection system and method according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some examples or embodiments of the present application, and for those skilled in the art, the present application can also be applied to other similar scenarios without creative labor. Unless it is clear from the language context or otherwise indicated, the same reference numbers in the drawings represent the same structure or operation.

[0028] As shown in the present application and claims, unless the context clearly indicates otherwise, the words "one", "a", "an", and / or "the" do not mean to specify a single number, but can also include a plurality. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the steps and elements explicitly identified, and these steps and elements do not constitute an exclusive list, and the method or device can also include other steps or elements.

[0029] Unless otherwise specifically indicated, the relative arrangement of the components and steps, numerical expressions, and values set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that the sizes of the various parts shown in the drawings are not drawn in accordance with the actual proportional relationship. The technology, methods and devices known to those skilled in the relevant art can not be discussed in detail, but in appropriate cases, the technology, methods and devices should be considered as part of the authorized specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, and not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0030] In the description of the application, it needs to be understood that the orientation words such as "front, back, up, down, left, right", "transverse, vertical, perpendicular, horizontal" and "top, bottom" and the like indicated orientation or position relationship is generally based on the orientation or position relationship shown in the drawings, only for the convenience of describing the application and simplifying the description, without making the opposite statement, these orientation words do not indicate and imply that the device or element referred to must have a particular orientation or be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the scope of protection of the application; the orientation words "inner, outer" refer to the inner and outer of the contour of each component itself.

[0031] For the convenience of description, spatial relative terms such as "over", "above", "upper surface", "upper" and the like can be used herein to describe the spatial positional relationship of one device or feature with other devices or features as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the drawings. For example, if the device in the drawing is inverted, the device described as "above" or "over" other devices or structures will be positioned "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0032] In addition, it needs to be pointed out that the use of "first", "second" and the like to define parts is only for the convenience of distinguishing the corresponding parts, and the above words have no special meaning unless otherwise stated, therefore, it cannot be understood as a limitation on the scope of protection of the application. In addition, although the terms used in the application are selected from the commonly known and used terms, some terms mentioned in the specification of the application may be selected by the applicant according to his or her judgment, and the detailed meaning of each term is explained in the relevant part of the description. In addition, the application is required to be understood not only by the actual terms used, but also by the meaning implied by each term.

[0033] It will be understood that when a component is referred to as being "on" or "connected to" or "coupled with" or "contacting" another component, it can be directly on, connected to, coupled with, or contacting the other component, or one or more intervening components can also be present. In contrast, when a component is referred to as being "directly on", "directly connected to", "directly coupled with", or "directly contacting" another component, there are no intervening components present. Similarly, when a first component is referred to as being "electrically contacting" or "electrically coupled with" a second component, there is an electrical path between the first component and the second component that allows current to flow. The electrical path can include capacitors, coupled inductors, and / or other components that allow current to flow, even if there is no direct contact between electrically conductive components.

[0034] The present application refers to Figure 1 A micro-zone transient temperature field detection system 10 is proposed, which can improve the accuracy and speed of micro-zone transient temperature field detection. As shown in Figure 1 The micro-zone transient temperature field detection system 10 mainly includes a light source module 11, a sensing module 12, a feedback control module 13, a dispersive element 111, and a data processing terminal 14.

[0035] Firstly, the light source module 11 is adapted to emit laser light, forming a laser path x in the extension direction of the emitted laser light, and Figure 1 The direction of the laser path x is schematically represented by an arrow, and it can be seen that the laser light passes through a plurality of components in turn and finally reaches the data processing terminal 14 after being emitted from the light source module 11. In this embodiment, the light source module 11 can be embodied as a broadband laser 101 with a high repetition rate, thereby achieving a high time resolution.

[0036] Further, the sensing module 12 includes a reference grating 103 and an atomic force probe 120, which are arranged in turn on the laser path x. Specifically, the atomic force probe 120 is adapted to scan the sample to be measured, and the laser light passes through the reference grating 103 and the atomic force probe 120 in turn on the laser path x and finally reaches the sample to be measured 105, thereby forming a detection signal carrying temperature sensing information of the sample to be measured 105.

[0037] Specifically, in this embodiment, the atomic force probe 120 includes a fiber grating nanometer probe 104 and a tuning fork 107, wherein the fiber grating nanometer probe 104 has a cladding 1041 and a core 1042 in turn from outside to inside in the radial direction, and the tuning fork 107 is adhered to the outside of the cladding 1041. The tuning fork 107 can be made of quartz material and directly adhered to the tuning fork 107 with optical ultraviolet glue. Preferably, in this embodiment, the reference grating 103 and the fiber grating nanometer probe 104 are connected in series on the same core 1042 and are wrapped by the same cladding 1041.

[0038] Preferably, in the present embodiment, the fiber grating nanoprobes 104 employ fiber Bragg gratings, and the tips of the fiber grating nanoprobes 104 can be prepared by means of hydrogen fluoride acid corrosion and the like. For example, when the two combined preparation means are employed, the prepared fiber can be fixed at both ends, heated to a molten state in the middle, and then stretched until broken at both ends to form a tapered region with gradually changing diameter, and then a nanoscale needle tip is formed at the tapered tip by chemical corrosion.

[0039] Further in such an embodiment, the reference grating 103 also employs a fiber Bragg grating, and the reflection wavelength range of the reference grating 103 and the reflection wavelength range of the fiber grating nanoprobes 104 do not intersect and / or coincide. As a kind of reflector, the fiber Bragg grating reflects light of a specific frequency when the light passes through it according to the structure of the fiber Bragg grating. In the micro-region transient temperature field detection system 10, the laser first passes through the reference grating 103 and then the fiber grating nanoprobes 104. By such a setting, the signal of the reference grating 103 and the temperature measurement sensing signal of the fiber grating nanoprobes 104 can be avoided from being mixed.

[0040] Continuing to refer to Figure 1 , the feedback control module 13 is connected to the atomic force probe 120 and is adapted to obtain a surface topography scanning result of the sample 105 to be measured after the atomic force probe 120 scans the sample 105 to be measured.

[0041] In the present embodiment, referring to Figure 1 , the feedback control module 13 is specifically implemented as a tuning fork feedback type atomic force control device 108, which is connected to the tuning fork 107 in the atomic force probe 120, and the tuning fork feedback type atomic force control device 108 is adapted to drive the atomic force probe 120 to move in three-dimensional space. To match this, preferably, in the present embodiment, the micro-region transient temperature field detection system 10 further comprises a three-dimensional displacement table 106 for carrying the sample 105 to be measured. At the same time, the three-dimensional displacement table 106 is adapted to move in three-dimensional space to enable the atomic force probe 120 to complete the scanning of the sample 105 to be measured.

[0042] As can be seen in Figure 1 , the dispersive element 111 is arranged on the laser path x, and the dispersive element 111 is adapted to process the above-mentioned detection signal, and the dispersion value of the dispersive element 111 is configured to meet the requirement value of mapping the frequency domain information of the detection signal to the time domain.

[0043] Finally, in Figure 1In the embodiment shown, the data processing terminal 14 is configured to combine the surface topography scanning result with the temperature sensing information processed by the spectrum inversion algorithm to obtain the temperature field distribution on the surface of the sample under test. Through the above system architecture arrangement and the application of the spectrum inversion algorithm, the spatial interval between two adjacent points in the temperature curve of the sample under test finally obtained reaches the nanometer level.

[0044] For the micro-transient temperature field detection system 10, the data processing terminal 14 can obtain the surface atomic force image of the sample under test 105 (i.e. the surface topography scanning result obtained by the feedback control module 13) and the corresponding temperature image at the same time by aligning the time stamp. On this basis, the data processing terminal 14 further obtains the temperature field distribution in the axial direction of the fiber Bragg probe 104 through the spectrum inversion algorithm, thereby obtaining the temperature longitudinal distribution on the surface and above the sample under test 105.

[0045] The spectrum inversion algorithm configured in the data processing terminal 14 includes an algorithm implemented by the following method: obtaining initial temperature information from the original grating reflection spectrum; calculating the inversion grating reflection spectrum by the transfer matrix method, combining the initial temperature information to calculate the error function, and calculating the difference between the actual grating reflection spectrum including the detection signal and the inversion grating reflection spectrum according to the error function; judging the relationship between the difference and the preset error value, when the difference is less than or equal to the preset error value, obtaining the inversion temperature field to obtain the temperature curve corresponding to the sample under test, otherwise iterating through the spectrum inversion algorithm, such as the correlation single-particle algorithm, until the difference between the actual grating reflection spectrum and the inversion grating reflection spectrum is less than or equal to the preset error value, and finally obtaining the inversion temperature field to obtain the temperature curve.

[0046] Further reference Figure 1 In order to enable the data processing terminal 14 to finally obtain data that can be processed, other components can be further configured as shown in Figure 1 For example, in this embodiment, the micro-transient temperature field detection system 10 further includes a circulator 102, which has a first end I, a second end II and a third end III. Specifically, the laser light emitted from the laser light source module 11 is first input to the circulator 102 through the first end I and output to the reference grating 103 through the second end II. And when the laser light forms a detection signal, the detection signal is input to the circulator 102 through the second end II and output through the third end III.

[0047] Further, in this embodiment, reference is made to Figure 1The micro-transient thermal field detection system 10 further comprises a dispersion element 111, a photoelectric detector 112 and a data acquisition device 113, which are arranged in sequence between the third end III of the circulator and the data processing terminal 14. Exemplarily, the dispersion element comprises a dispersion device composed of a mirror, a chirped grating, a dispersion compensation fiber, a grating pair and / or a single-mode fiber, and the dispersion element can be used in any combination of the above or alone, and the present application is not limited in this regard. In addition, the photoelectric detector 112 is adapted to convert the optical signal contained in the detection signal into an electrical signal, and the data acquisition device 113 transmits the data to the data processing terminal 14 after completing the data acquisition of the electrical signal.

[0048] In the embodiment, the micro-transient thermal field detection system 10 further comprises a coupler 109 and a spectrometer 110, and the detection signal is dispersed into a first detection signal and a second detection signal through the coupler 109 before reaching the dispersion element 111, wherein the first detection signal is transmitted to the spectrometer 110, and the second detection signal is transmitted to the dispersion element 111.

[0049] It should be noted that the present embodiment applies the time stretching-dispersion Fourier transform technology, which is characterized by mapping the frequency domain information to the time domain, and finally the frequency domain information mapped to the time domain can be obtained by combining the photoelectric detector 112 and the data acquisition device 14 (such as an oscilloscope) at high speed. This mapping is mainly obtained by expanding each laser pulse in the time domain, that is, the repetition frequency of the light source module 11 (such as a laser) represents the speed of obtaining the spectrum. Therefore, a broadband laser 101 with a high repetition frequency is preferred here. In addition to the high repetition frequency, the broadband ensures that the frequency shift of the FBG probe (such as the fiber grating nanoprobe 104) after being subjected to temperature changes does not exceed the spectral range of the laser. This is because once the spectral range of the laser is exceeded, there is no reflected spectrum returned, and at this time there is no way to obtain the demodulation result. Therefore, in the embodiment shown in the present application, a laser with a MHz repetition frequency and a 3dB bandwidth of more than 20nm is preferred. However, the present application is not limited in this regard, and actual instrument selection can also be selected according to actual measurement requirements. Figure 1

[0050] ​It should be noted that in the above technical solution of the present application, the resolution of the order of 100 microns obtained by the spectral inversion algorithm is the axial direction of the optical fiber; and on this basis, combined with atomic force microscopy technology, the spatial interval of the sample surface can be obtained to be of the order of nanometers. In this technical solution, when the probe scans the sample for imaging, the time for obtaining the entire region imaging is determined by the scanning speed of the probe (sample) displacement table, which is usually relatively long, and is generally more than 10 minutes according to the region size and scanning accuracy. However, for the single-point speed, the time resolution can reach nanosecond level. Therefore, as a whole, the above technical solution of the present application can improve the accuracy and speed of micro-transient temperature field detection, and the detection result has high spatial and high temporal resolution. In order to better understand the architecture of the micro-transient temperature field detection system 10, Figure 2 as shown in the figure. Figure 1 as shown in the figure. Referring to Figure 2 as shown in the figure. Figure 1 The light source module 11 specifically selects a film locking laser, which includes a 980nm light source 200, a coupler 201, an erbium-doped optical fiber 202, a wavelength division multiplexer 203, two polarization controllers 204, a polarization-dependent isolator 205, and the like. After the laser is emitted from the light source module 11, it is output to the reference grating 103 and the atomic force probe 120 (including the fiber grating nanometer probe 104 and the tuning fork 107) through the circulator 102, and then reaches the sample to be measured 105 located on the three-dimensional displacement table 106. The tuning fork 107 is connected to the feedback control module 13, and cooperates with the three-dimensional displacement table 106 to complete the scanning of the sample to be measured 105. In this embodiment, the sample to be measured 105 is located on the sample table 1050 and is located on the three-dimensional displacement table 106 together, and a thermocouple 1051 is further arranged above the sample to be measured 105, which is used for temperature calibration before formal measurement. The signal carrying the temperature sensing information of the sample to be measured 105 is output to the coupler 109 again through the circulator 102, and is dispersed into a first detection signal and a second detection signal, wherein the first detection signal is transmitted to the spectrometer 110, and the second detection signal is transmitted to the dispersion element 111. The second detection signal passes through the photodetector 112 and the high-speed oscilloscope 113 in sequence to complete data acquisition, and then reaches the data processing terminal 14 Figure 1 as shown in the figure. Figure 2 (not shown).

[0051] The application proposes a system of preparing fiber grating (for example, Bragg fiber grating FBG) into a tapered probe, combining with a tuning fork feedback type atomic force control module to complete the approach of the probe to the sample surface and the scanning of the sample surface, and applying time stretching-dispersion Fourier transform technology to complete the high-speed demodulation of optical signal. The system is divided into four modules: an optical source module composed of a broadband laser with high repetition frequency; a sensing module composed of a reference grating, an FBG probe and a tuning fork; a feedback control module composed of a tuning fork feedback type atomic force control system; and a data acquisition module composed of a photodetector, a dispersion medium and a data acquisition device. The principle of the system is based on the characteristics of the optical source itself with high repetition frequency. The information of the FBG probe reflection spectrum can be mapped to the time domain through the action of the dispersion element by using the time stretching-dispersion Fourier transform technology, so that the spectrum can achieve nanosecond-level time resolution. In addition, by combining the FBG prepared into a tapered probe with the tuning fork, the scanning of the probe to the sample surface topography is completed by using the tuning fork feedback type atomic force control module. Based on the size of the probe tip, the transverse spatial resolution can reach nanometer level. Finally, the obtained spectrum is combined with the spectrum inversion algorithm, such as the Correlative Single Particle (CSP) algorithm, to obtain the longitudinal spatial resolution of nanometer level along the grating axial direction.

[0052] Another aspect of the present application refers to Figure 3 A micro-zone transient temperature field detection method 30 is proposed, which specifically includes the following steps.

[0053] Step 11 is to emit laser light through the light source module.

[0054] Step 12 is to scan the sample to be measured by the atomic force probe, and obtain the surface topography scanning result of the sample to be measured.

[0055] Step 13 is to make the laser light pass through the reference grating and the atomic force probe in the sensing module in turn and reach the sample to be measured to form a detection signal. The detection signal carries the temperature sensing information of the sample to be measured.

[0056] Step 14 is to transmit the detection signal to the data processing terminal after being processed by the dispersion element, and process the temperature sensing information according to the spectrum inversion algorithm through the data processing terminal, and combine the surface topography scanning result to obtain the temperature field distribution of the sample surface to be measured. The dispersion value of the dispersion element is configured to meet the requirement value of mapping the frequency domain information of the detection signal to the time domain.

[0057] Preferably, the spectrum inversion algorithm method proposed in the above step 14 comprises the following steps: obtaining initial temperature information through the original grating reflectance spectrum; calculating the inversion grating reflectance spectrum through the transfer matrix method, combining the initial temperature information to calculate the error function, and calculating the difference between the actual grating reflectance spectrum including the detection signal and the inversion grating reflectance spectrum according to the error function; judging the relationship between the difference and the preset error value, when the difference is less than or equal to the preset error value, the inversion temperature field is obtained, so as to obtain the temperature curve corresponding to the chip to be measured, otherwise, through the spectrum inversion algorithm, for example, the correlation single particle algorithm is iterated, until the difference between the actual grating reflectance spectrum and the inversion grating reflectance spectrum is less than or equal to the preset error value, and finally the inversion temperature field is obtained to obtain the temperature curve.

[0058] The above micro-region transient temperature field detection method 30 can be applied to the micro-region transient temperature field detection system 10 described above with reference to Figure 1 and Figure 2 The above micro-region transient temperature field detection method 30 can be applied to the micro-region transient temperature field detection system 10 described above with reference to

[0059] Flowcharts have been used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the foregoing or the following operations are not necessarily performed in sequence. On the contrary, various steps can be processed in reverse order or simultaneously. Meanwhile, other operations can be added to these processes, or one or more steps of operations can be removed from these processes.

[0060] For example, the temperature calibration curve of a sample to be measured obtained by the micro-region transient temperature field detection system and method proposed in the present application through TS-DFT and the temperature calibration curve obtained by the spectrometer. Among them, the dashed curve represents the change of the center peak position of the probe reflectance spectrum obtained by the spectrometer, and the solid curve represents the change of the center peak position of the oscilloscope data converted into frequency spectrum through time stretching-dispersion Fourier transform. From the two curves, it can be seen that the data obtained by time stretching-dispersion Fourier transform and the data obtained by the spectrometer are consistent in trend, which can demonstrate the accuracy of the former data. Some subtle differences are because the data obtained by the spectrometer is the average of a period of time rather than the transient temperature change. In summary, the measurement data obtained by time stretching-dispersion Fourier transform of the present application has effectiveness and accuracy, and can improve the accuracy and speed of micro-region transient temperature field detection when applied, and make the detection result have high spatial and high temporal resolution.

[0061] Having described the basic concepts, it is obvious to those skilled in the art that the above-described application discloses only examples and does not limit the present application. Although not explicitly described, those skilled in the art can make various modifications, improvements and corrections to the present application. Such modifications, improvements and corrections are suggested in the present application, so such modifications, improvements and corrections still belong to the spirit and scope of the exemplary embodiments of the present application.

[0062] Meanwhile, specific words are used in the present application to describe the embodiments of the present application. As "one embodiment", "an embodiment", and / or "some embodiments" mean a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned in different places in the specification does not necessarily mean the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be properly combined.

[0063] Some aspects of the present application can be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software can be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". The processor can be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors or combinations thereof. In addition, aspects of the present application can be embodied as a computer product located in one or more computer readable media, including computer readable program code. For example, the computer readable medium can include, but is not limited to, magnetic storage devices (e.g., hard disk, floppy disk, magnetic tape...), optical disks (e.g., compact disk CD, digital versatile disk DVD...), smart cards and flash memory devices (e.g., card, stick, key drive...).

[0064] The computer readable medium can contain a propagated data signal with computer program code embodied therein, for example, in baseband or as part of a carrier wave. Such propagated signal can take various forms, including but not limited to electromagnetic, optical or any suitable combination thereof. The computer readable medium can be any computer readable medium other than a computer readable storage medium that can be connected, communicated, propagated or transmitted to an instruction execution system, device or apparatus for use with the program. The program code embodied on the computer readable medium can be propagated by any suitable medium, including wireless, cable, optical fiber cable, radio frequency signals or the like, or any suitable combination thereof.

[0065] For simplicity and to help with understanding of one or more embodiments of the application, the description of embodiments of the application above sometimes refers to a combination of features in one embodiment, drawing, or description of an embodiment. This method of disclosure is not to be interpreted as reflecting an intention that the application requires more features than are explicitly mentioned in each claim. Indeed, reference to

[0066] Some embodiments use numerals to describe components, quantities of attributes. It should be understood that such numerals used in the description of embodiments are, in some examples, modified by the adjectives "about," "approximately," or "substantially." Unless otherwise stated, "about," "approximately," or "substantially" indicate that the described numeral can vary ±20%. Accordingly, numerical parameters in the description and claims are approximations, and thus can vary depending upon the requirements of the particular embodiments. In some embodiments, numerical parameters are provided as approximations that can vary depending on the desired properties sought to be obtained by the particular embodiments. In some embodiments, numerical parameters are determined by the limitations inherent in the various components used to practice the embodiments. Although the numerical ranges and parameters setting forth the broadest scope of the embodiments of the application are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values set forth in the specific examples are provided to be as precise as practicable.

[0067] Although the application has been described with reference to the current embodiments, persons having ordinary skill in the art will recognize that changes can be made in form and detail without departing from the spirit and the scope of the application. Therefore, the disclosed embodiments should be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

Claims

1. A micro-area transient temperature field detection system, characterized in that, include: A light source module, adapted to emit laser light, forms a laser path in the direction in which the emitted laser light extends; A sensing module, including a reference grating and an atomic force probe, is arranged sequentially on the laser path. The atomic force probe is adapted to scan the sample to be tested. The laser passes sequentially through the reference grating and the atomic force probe on the laser path and reaches the sample to be tested to form a detection signal. The detection signal carries the temperature sensing information of the sample to be tested. The atomic force probe includes a fiber grating nanoprobe and a tuning fork. The fiber grating nanoprobe has a cladding and a core in the radial direction from the outside to the inside. The tuning fork is adhered to the outside of the cladding. The reference grating and the fiber grating nanoprobe are connected in series on the same core and are wrapped by the same section of the cladding. A feedback control module is connected to the atomic force probe in the sensing module. The feedback control module is adapted to obtain the surface morphology scanning result of the sample to be tested after the atomic force probe scans the sample to be tested. A dispersive element, arranged on the laser path, is adapted to process the detection signal, and the dispersion value of the dispersive element is configured to satisfy the requirement of mapping the frequency domain information of the detection signal to the time domain; and The data processing terminal is configured to process the temperature sensing information using a spectral inversion algorithm and then combine it with the surface morphology scanning results to obtain the temperature field distribution on the surface of the sample to be tested.

2. The micro-area transient temperature field detection system as described in claim 1, characterized in that, The fiber Bragg grating nanoprobe is made of fiber Bragg grating, and the tip of the fiber Bragg grating nanoprobe is prepared by hydrofluoric acid etching.

3. The micro-area transient temperature field detection system as described in claim 2, characterized in that, The reference grating is also a fiber Bragg grating, and the reflection wavelength range of the reference grating does not intersect and / or coincide with the reflection wavelength range of the fiber Bragg grating nanoprobe.

4. The micro-area transient temperature field detection system as described in claim 1, characterized in that, The feedback control module includes a tuning fork feedback atomic force control device connected to the tuning fork in the atomic force probe. The tuning fork feedback atomic force control device is adapted to drive the atomic force probe to move in three-dimensional space.

5. The micro-area transient temperature field detection system as described in claim 4, characterized in that, It also includes a three-dimensional displacement stage for carrying the sample to be tested, the three-dimensional displacement stage being adapted to move in three-dimensional space so that the atomic force probe can complete the scanning of the sample to be tested.

6. The micro-area transient temperature field detection system as described in claim 1, characterized in that, It also includes a circulator having a first end, a second end, and a third end, wherein, The laser emitted from the light source module is first input to the circulator via the first end, and then output to the reference grating via the second end; and Once the laser beam is generated as the detection signal, the detection signal is input to the circulator through the second terminal and output through the third terminal.

7. The micro-area transient temperature field detection system as described in claim 6, characterized in that, It also includes a photodetector and a data acquisition device, wherein the dispersive element, the photodetector, and the data acquisition device are sequentially arranged between the third end of the circulator and the data processing terminal, wherein, The photodetector is adapted to convert the optical signal contained in the detection signal into an electrical signal. After the electrical signal is transmitted to the data acquisition device, the data acquisition device is adapted to transmit the data to the data processing terminal after completing the data acquisition of the electrical signal.

8. The micro-area transient temperature field detection system as described in claim 7, characterized in that, It also includes a coupler and a spectrometer. Before reaching the dispersive element, the detection signal passes through the coupler and is dispersed into a first detection signal and a second detection signal. The first detection signal is transmitted to the spectrometer, and the second detection signal is transmitted to the dispersive element.

9. The micro-area transient temperature field detection system as described in claim 7, characterized in that, The dispersive elements include a dispersive device composed of mirrors, a chirped grating, a dispersion-compensating fiber, a grating pair, and / or a single-mode fiber.

10. The micro-area transient temperature field detection system according to any one of claims 1 to 9, characterized in that, The spectral inversion algorithm includes an algorithm implemented in the following manner: Initial temperature information is obtained by using the original grating reflection spectrum; The inverted grating reflection spectrum is calculated using the transfer matrix method, and an error function is calculated based on the initial temperature information. The difference between the actual grating reflection spectrum, including the detected signal, and the inverted grating reflection spectrum is then calculated based on the error function. The relationship between the difference and the preset error value is determined. When the difference is less than or equal to the preset error value, the inverted temperature field is obtained to obtain the temperature curve corresponding to the sample to be tested. Otherwise, the spectral inversion algorithm is iterated until the difference between the actual grating reflection spectrum and the inverted grating reflection spectrum is less than or equal to the preset error value, and finally the inverted temperature field is obtained to obtain the temperature curve.

11. A method for detecting transient temperature fields in a micro-region, characterized in that, The method, applicable to the micro-area transient temperature field detection system as described in any one of claims 1 to 10, comprises the following steps: Laser light is emitted through the light source module; The sample under test is scanned using an atomic force probe, and the surface morphology scanning results of the sample under test are obtained. The laser is sequentially passed through the reference grating in the sensing module and the atomic force probe and then reaches the sample to be tested to form a detection signal, which carries the temperature sensing information of the sample to be tested. as well as The detection signal is processed by a dispersive element and then transmitted to a data processing terminal. The data processing terminal processes the temperature sensing information according to a spectral inversion algorithm and combines it with the surface morphology scanning results to obtain the temperature field distribution of the sample surface under test. The dispersive value of the dispersive element is configured to meet the requirement of mapping the frequency domain information of the detection signal to the time domain.

12. The micro-region transient temperature field detection method as described in claim 11, characterized in that, The spectral inversion algorithm method includes the following steps: Initial temperature information is obtained by using the original grating reflection spectrum; The inverted grating reflection spectrum is calculated using the transfer matrix method, and an error function is calculated based on the initial temperature information. The difference between the actual grating reflection spectrum, including the detected signal, and the inverted grating reflection spectrum is then calculated based on the error function. The relationship between the difference and the preset error value is determined. When the difference is less than or equal to the preset error value, the inverted temperature field is obtained to obtain the temperature curve corresponding to the sample to be tested. Otherwise, the relevant single-event algorithm is used for iteration until the difference between the actual grating reflection spectrum and the inverted grating reflection spectrum is less than or equal to the preset error value, and finally the inverted temperature field is obtained to obtain the temperature curve.

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