TW201042251A - Thermal conductivity measurement system for one dimension material and measurement method thereof - Google Patents

Abstract

The invention relates to a thermal conductivity measurement system for one dimension material. The system includes an object placing device, a geometric parameter obtaining module, a characteristic peak frequency value of the Raman-spectra obtaining module, a thermal power obtaining module, a comparing module and a calculation module. The characteristic peak frequency value of the Raman-spectra obtaining module is used to obtain a characteristic peak frequency value of the Raman-spectra of a middle area of the suspended parts of the object which is regarded as an initial value, and to obtain a characteristic peak frequency value of the Raman-spectra of any end point of the suspended parts of the object when the object is self-heated by current and reach a heat balance. The calculation module is used to calculate the thermal conductivity of the object according to the temperature difference between the middle area and the any end point of the suspended parts of the object, the geometric parameters of the object and the thermal power of the object. The invention also relates to a method for using the thermal conductivity measurement system to obtain the thermal conductivity of the object.

Description

201042251 VI. Description of the Invention: [Technical Field of the Invention] [0001] The present invention relates to a measurement system and a measurement method, and more particularly to a one-dimensional material thermal conductivity measurement system and method. [Prior Art] [0002] Thermal conductivity is an important parameter of the thermal properties of reactive materials. Therefore, in applications such as engineering heat dissipation, it is especially important to select materials with suitable thermal conductivity, so the thermal conductivity of various materials can be accurately measured. Engineering applications are important. [0003] When the measured object whose thermal conductivity needs to be measured is a one-dimensional nano material, such as a nanowire, a single carbon nanotube, a carbon nanotube bundle or a nanocarbon pipeline, the thermal conductivity is measured. It has been difficult. Because in the thermal conductivity measurement, it is necessary to obtain the temperature difference of the measured object in a certain area. However, for one-dimensional nanomaterials, since the characteristic width of their cross-section is within 100 nm, the area where the temperature of the measured object needs to be measured is on the order of micrometers (20 micrometers), and the conventional temperature measuring tool does not have such accurate measurement. Resolution. Therefore, it is difficult to measure the temperature difference of a one-dimensional nanomaterial in a certain area with a conventional temperature measuring tool, even if it is measured, it is not accurate. [0004] The heat capacity of a substance is proportional to its mass. Generally, the quality of a one-dimensional nanomaterial in a small-scale temperature measurement region is small, so that the heat capacity of the one-dimensional nanomaterial in this region is also small. If the direct contact type temperature measurement method is used, when the temperature probe of the thermometer is in contact with the one-dimensional nano material, the local temperature of the one-dimensional nano material is rapidly changed until it contacts the temperature detecting device. The temperature is the same. The temperature probe is usually a macroscopic body with a large heat capacity. In the small-scale temperature measurement area, the one-dimensional nanomaterial 098117906 Form No. A0101 Page 4 / Total 36 page 0982030438-0 201042251 The heat released is very small for the probe temperature. . Thus, the traditional temperature measurement method can not only measure the temperature of the one-dimensional nanomaterial, but also seriously affect the thermal state of the one-dimensional nanomaterial. In addition, because the size of the one-dimensional nanomaterial is small, the temperature difference between the points of the measured object cannot be accurately measured, and the measurement of the thermal conductivity related to the temperature difference cannot be performed. In the same way, the thermal conductivity measurement of the Vennite material has the same problem as the thermal conductivity measurement of the one-dimensional micron material. SUMMARY OF THE INVENTION [0005] In view of this, it is necessary to provide a one-dimensional material thermal conductivity measuring system and a measuring method thereof, and the measuring system and the measuring method thereof can measure the measured object as a one-dimensional nano material or The thermal conductivity of a one-dimensional micron material. The present invention relates to a one-dimensional material thermal conductivity measuring system for measuring the thermal conductivity of a measured object. The one-dimensional material thermal conductivity measuring system includes a measured object placing device, a geometric size acquiring module, a Raman spectral characteristic peak frequency value acquiring module, a thermal power acquiring module, and a comparison.

* I module, and a calculation module. The object placement device includes at least four electrodes disposed between the spacers. The object to be tested is disposed on the surface of the four electrodes, and a portion of the object to be tested between the two electrodes is suspended. The Raman spectral characteristic peak frequency value obtaining module is configured to obtain a characteristic peak frequency value of a Raman spectrum of a suspended point central point of the suspended object after self-heating by a current and a thermal equilibrium as an initial value and a suspended portion of the measured object The characteristic peak frequency of the Raman spectrum at either end. The thermal power acquisition module is configured to obtain thermal power transmitted along a suspended portion of the object to be tested. The geometry acquisition module is configured to acquire a desired geometric size of the measured object. The comparison module is configured to compare the difference between the characteristic peak frequency values of the center point of the suspended portion of the test object and the Raman spectrum of the any end point, 098117906, Form No. A0101, Page 5 of 36, 0982030438-0 201042251, to obtain the The temperature difference between the center point and any end point of the suspended portion of the object. The calculation module is configured to calculate a thermal conductivity of the measured object according to a temperature difference, a geometric size, and a thermal power of a center point and an end point of the suspended portion of the measured object. [0007] A one-dimensional material thermal conductivity measuring method, comprising the steps of: providing a measured object placing device, the measuring object placing device comprising at least four electrodes arranged at intervals; obtaining a desired object to be tested Geometry; the object to be tested is placed on the surface of the four electrodes of the device to be tested, and the portion of the object to be measured between the two electrodes is suspended, and the two electrodes on the outside pass a constant current to the object to be tested. The measured object self-heats under the action of current, and reaches the heat balance after a period of time; obtains the characteristic peak frequency value of the Raman spectrum of the dangling point of the measured object as the initial value and any end point of the suspended part of the measured object The characteristic peak frequency value of the Raman spectrum, and comparing the difference between the characteristic peak frequency value of the center point of the suspended portion of the measured object and the Raman spectrum of any end point; obtaining the thermal power transmitted along the axial direction of the suspended portion of the measured object; The difference between the characteristic peak frequency of the floating point of the measured object and the Raman spectrum of any end point obtains the temperature difference between the center point and any end point of the suspended portion of the measured object; according to the center of the suspended portion of the measured object The thermal conductivity of the test object is calculated from the temperature difference, the geometric size, and the thermal power of the point. [0008] Compared with the prior art, the thermal conductivity measuring system and the measuring method provided by the present invention can avoid the contact of an object having a large heat capacity with a one-dimensional material by using a non-contact spectral measuring method, so that the temperature of the one-dimensional material is stable. To make the measurement results more accurate. Embodiments [0009] Hereinafter, a dimensional material thermal conductivity 098117906 will be provided in accordance with an embodiment of the present invention with reference to the accompanying drawings. Form No. 1010101 Page 6/36 pages 0992030438-0 201042251 [0010] Ο ❹ [0011] 098117906 Measurement System And its measurement methods are further explained. Referring to FIG. 1 and FIG. 2, a thermal conductivity measuring system 100 for measuring the thermal conductivity of a measured object 220 is provided. The thermal conductivity measuring system 1 〇〇 includes a measured object placing device 1 , a geometric size acquiring module 20 , a Raman spectral characteristic peak frequency obtaining module 3 , a power acquiring module 40 , a comparing module 50 , and A calculation module 6〇. The object placement device 10 includes at least four electrodes disposed at intervals, and the object to be tested 220 is disposed on the surface of the four electrodes, and the portion of the object to be measured 2 2 悬 between the two electrodes is suspended. The geometric dimension acquisition module 20 is configured to obtain the required measured object: the object 220: The Raman spectral characteristic peak frequency value obtaining module 30 is configured to obtain the characteristic peak frequency value of the Raman spectrum of the dangling portion of the datum portion after the self-heating of the measured object 220 and the thermal equilibrium is reached as an initial value, and the measured object is suspended. The characteristic peak frequency value of the Raman spectrum of any of the endpoints is used to obtain the thermal power conducted along the axial portion of the suspended portion of the object under test 220. The comparison module 50 is configured to compare the object to be tested 220. The difference between the characteristic peak frequency values of the Raman spectrum of the dangling portion center point and the #-end point is obtained to obtain the temperature difference between the center point and any end point of the suspended portion of the object to be tested 220. The calculation module 60 is configured to calculate the thermal conductivity of the object to be tested 220 according to the temperature difference, the geometric size, and the thermal power of the center point and the end point of the suspended portion of the object 220. The object to be tested 220 is a one-dimensional material, and the one-dimensional material is a one-dimensional nano material or a one-dimensional micro material. The one-dimensional nanomaterial is a nanotube, a nanorod, a nanowire, a nanofiber or a nanobelt. Specifically, in the embodiment, the object to be tested 2 2 0 is a single-walled carbon nanotube. Referring to FIG. 2, the DUT 10 includes a substrate 111, a form number Α0101, a page 7/36 S 0982030438 〇[0012] 201042251 A carrier 1U'-a second carrier 1 〖5, a The first insulating layer 112, a first insulating layer 113, a first electrode 116, a second electrode 117, a second electrode 118, and a fourth electrode H9. The first carrier 114 and the second carrier 115 are spaced apart from each other on the surface of the substrate in. The first insulating layer 112 is disposed on the surface of the first carrier 114. The second insulating layer 113 is disposed on the surface of the second carrier 115. In this embodiment, the first carrier 114 and the second carrier 115 are arranged side by side on the surface of the substrate hi, and the first carrier 114, the first carrier 115 and the substrate 111 are integrally formed. The four electrodes are spaced apart, and the object to be tested 220 is in contact with the four electrodes, and a portion of the object to be tested 22 located between the two electrodes is suspended. In this embodiment, the first electrode 116 and the second electrode 117 are spaced apart from each other and disposed on the surface of the first insulating layer 112. The third electrode 丨18 and the fourth electrode 119 are disposed side by side on the surface of the second insulating layer 113, and one end of the object to be tested 220 is placed on the surface of the first electrode 116 and the second electrode 117. One end is placed on the surface of the third electrode 118 and the fourth electrode 119. The one-dimensional object to be tested 220 is perpendicular to the four electrodes of the device to be placed. The first electrode 116 and the fourth electrode lig are connected in series with the object to be tested 220 by a power source (not shown) and an ammeter (not shown) to form a circuit. The second electrode 117 and the third electrode 118 are connected to a voltmeter. At this time, the two points in contact with the second electrode 117 and the third electrode 118 become the two end points of the suspended portion of the object to be tested 220. The first end point of the suspended portion of the object to be tested 220 is marked as , and the second end point is marked as , and correspondingly, the center points of the two end points are marked as 〇. The material of the insulating layer 113 is an electrically insulating and heat insulating material. In this embodiment, the insulating layer 213 is cerium oxide. 098117906 Form No. A0101 Page 8/36 Page 0992030438-0 [(8) 13] 201042251 [0015] [0015] The materials of the first electrode U6, the second electrode 117, the third electrode 11 8 and the fourth $ pole 119 It may be molybdenum, platinum or nickel. In the present embodiment, the electrode 116, the second electrode 117, the third electrode 118, and the fourth electrode 119 are molybdenum electrodes. The geometry acquisition module 20 is configured to measure the length AL of the suspended portion of the object to be tested 220, and the geometrical dimensions such as the cross-sectional area of the object to be tested 220. among them

The length Δ of the suspended portion of the object 2 2 is the distance between the second electrode 117 and the third electrode 118 of the device to be placed 1 . The geometric size acquisition module 20 realizes its function by the measuring object placing device 1 and the microscope. If the cross-section of the object to be tested is circular, the diameter d of the circle is measured, and the area of the circular cross-sectional surface is S=0. 257r (i2. If the cross-section of the object 220 is a circle Ring, measure the outer diameter R of the cross section of the ring and the thickness b of the ring wall to obtain the area of the cross section of the ring

. In this embodiment, the object to be tested 220 is a single-walled carbon nanotube, and the length of the carbon nanotube is suspended by f.

AL was measured by scanning electron microscopy to give a thickness of 3 μm. The inner diameter of the carbon nanotubes is 1. 8 nm. For the inner diameter of the carbon nanotubes, the outer diameter R of the carbon nanotubes is measured by an atomic force microscopy (A, the 'AFM). The wall thickness of the single-walled m-meter tube is approximately a constant 'b=0.34 nm. Tian Gu, the area of the measured object 2 2 0 098117906

Page 9 of 36 Form No. A0101 0982030438-0 201042251 [0016] The Raman spectral characteristic peak frequency value acquisition module 30 is configured to acquire the measured object 2 2 0 self-heating under the action of current and reach thermal equilibrium. The characteristic peak frequency value of the Raman spectrum of the center point of the suspended portion is taken as the initial value and the characteristic peak frequency value of the Raman spectrum of any end point of the object 2 2 〇 floating portion. The Raman spectral characteristic peak frequency value obtaining module 30 obtains the above data according to the material of the measured object 220 by the object placing device 10, the measuring circuit, the Raman spectrometer and a vacuum chamber 230, and the required Raman is measured. The characteristic peak frequency values of the spectrum are also different. For the nanotube, the characteristic peak frequency of the Raman spectrum to be measured is its (peak. The measured object 22 〇 'the object placement device 10 and the measurement circuit are located in the true cavity 2 3 The vacuum chamber 230 is a vacuum quartz tube or a stainless steel vacuum chamber having a quartz window. The object to be tested 220 is located at the first electrode 116, the second electrode 117, and the third of the object placing device 10. The surface of the electrode 118 and the fourth electrode 119. The electric current flows into the object to be tested 22 via the first electrode 116 and flows out of the object to be tested 220 via the fourth electrode jig. The second electrode 11 7 and the third electrode 118 are connected to the voltmeter. To measure the voltage of the suspended portion of the object to be tested 220 [j. The degree of vacuum in the vacuum chamber 230 is 10 4 Torr, so the heat energy transmitted by the object 22 〇 through the surrounding air can be neglected. With respect to the heating power, The infrared radiant energy of the measured object 2 2 也 is also very small, so as to ensure that the thermal state of the suspended portion of the measured object 2 2 不变 is unchanged. The measured object 220 self-heats under the action of the current, after being heated for a period of time, is measured Each point on the suspended portion of the object 220 has a stable temperature distribution, that is, The intermediate temperature of the object 220 is high, and the temperature on both sides is low. Therefore, the thermal power transmitted along the axial direction of the object to be tested 220 is equal to the total heat power generated by the current. The Raman spectrometer is used to obtain either end of the suspended portion of the object to be tested 220. 098117906 Form No. 1010101 Page 10/36 Page 0992030438-0 201042251 Point L or 1^ and the Raman spectrum of the center point of the suspended portion of the object 220. The highest peak of the complex peaks in the Raman spectrum 5纳米。 In the present embodiment, the measured object 220 is a single-walled carbon nanotube, the characteristic peak to be measured is the carbon peak frequency of the Raman spectrum of the carbon nanotubes, using 514.5 nm The laser is used as the excitation source. Please refer to Figure 3. The Raman spectrum of the single-walled carbon nanotube in the suspended portion of the Raman spectrum corresponds to the Raman frequency system 1567. 6cffl-i ' 壬 - the end point, or The Raman frequency value corresponding to the G-peak of the Raman spectrum is 1577.7 cm-1 » ❹ # The thermal power acquisition module 40 can obtain the thermal power transmitted along the suspended portion of the workpiece 220. The thermal power acquisition module 4〇 It is realized by the object to be measured - =1G, the measuring circuit and the vacuum chamber 23Q. The test object placement device 1 and the measurement circuit are both located in the vacuum cavity. After the first electrode 116 and the fourth electrode 119 pass the test object (10) to the motor, the total thermal energy generated is along the object 22 〇Axial conduction = the sum of heat, infrared ray energy and ambient heat conduction. In the example of this figure, the vacuum chamber gives a vacuum of 10-4 Torr, so the heat energy transmitted through the air can be ignored. In the embodiment, the motor of the test object 220 is 0.298 microamperes, and the voltage of the suspended portion of the test object 220 measured by the voltmeter connected to the second i pole 117 and the third electrode 118 is 1. 175 volts. Therefore, the heating power can be calculated as ^the external eigen energy squeaking...(10)^化' At this time, the Stef an-Bol tzmann law (F = σ τ4) is applied, where σ 098117906 m 5' 67 xl0_8ff/ (m2 · κ4) is a constant, s is the surface area of a single-walled suspension, S = 7rdx2L. Assume that the entire suspended single-walled nanocarbon 0902030 single nickname A0101 page 11 / 36 pages ΠΟ) 201042251 [0018] [(8) 19] [0020] 098117906 The temperature of the tube is 700K, the calculated infrared radiation energy is Pradiati〇n = 3. 15xlO_9W 'only one percent of the heating power. Therefore, when the suspended object 220 is subjected to self-heating by current, the total thermal energy P = U1 is equal to the amount of heat conducted along the axial portion of the suspended portion of the object 220. The thermal power of the axial conduction is equal to the power of the current heating. The comparison module 50 is configured to acquire a temperature difference between the center point 0 of the object to be tested 220 and any one of the terminals 1 or 19. The difference between the peak frequency value of the Raman spectrum characteristic of the measured object 220 and the temperature point curve and the center point 悬 of the suspended portion of the object 220 and the peak frequency value of the 孓 characteristic of the Raman spectrum of any end point h or 1^ are obtained. The temperature between the center point 0 of the object 220 and either end point 1^ or 1^2 is the difference. In this embodiment, referring to FIG. 8 , the object to be tested 220 is a single-walled carbon nanotube. The curve of the peak value of the G peak in the Raman spectrum of the carbon nanotube is a straight line, and the slope of the line is K. . Therefore, the temperature difference between the center point 0 and any end point of the suspended portion of the carbon nanotube can be satisfied by the following relationship: AT = ΚΔΟ where K is the Raman spectrum of the nanometer *reverse tube (j peak The slope of the line whose frequency changes with temperature; ΔΤ is the center point of the suspended portion of the carbon nanotube and any end point [1 or the temperature difference; Δ(ϊ is the center point of the suspended portion of the carbon nanotube and any end point L The difference of the G peak frequency value of 1L2. In this embodiment, the difference between the G peak frequency value of the Raman spectrum of the center point G of the single-walled carbon nanotube and the 1st point or the Raman spectrum is 1567·6cm— I_1577. 7cm2-1=_1〇lcm_], the slope of the straight line of the G-peak frequency of the Raman spectrum of the single-walled carbon nanotube with temperature changes K = -0.0257 cnf^K» Therefore, the carbon nanotube is suspended in the portion Page 12 of 36 Form No. Α0101 0982030438-0 201042251 The temperature difference between the heart point and any end point h or △ Τ = (-10· lcm-1 ) (-0. 0257 ¢: ^/1() = 3931 (. [0021] The calculation module 60 is used to calculate the thermal conductivity of the measured object 220, and the calculation of the thermal conductivity satisfies the following relationship: [0022] where 'k is the heat of the measured object 220 Rate; u is the voltage of the suspended portion of the test object 220; I is the current flowing through the test object 220; the length of the suspended portion of the test object 220; S is the cross-sectional area of the test object 220; ΔΤ is the measured object The temperature difference between the center point 0 of the suspended portion and any one end point, or 1^. In this embodiment, the cross-sectional area of the carbon nanotubes obtained by each of the above modules is S=TT(2R-b)b=l. 1084 平方 square nanometer, ΔΤ = 393K, △ L = 30 μm, and P = UI = 3.5xl 〇 -7w substituted into the relationship of the thermal specific rate, the thermal conductivity rate of the nano tube is obtained. [0023] Therefore, the thermal conductivity of the single-walled carbon nanotube is 2400 W/m K. [0024] Please refer to FIG. 4, which is a flow chart of the method for measuring the thermal conductivity of the one-dimensional material. Therefore, the method of measuring 1 'f thermal conductivity includes the following steps: [0025] Step S101, a device 1 is provided, and the device to be tested 10 includes at least four electrodes arranged at intervals. In step S102, the required geometric shape of the object to be tested 220 is obtained. [0027] Step S103, the object to be tested 220 is placed on the surface of the four electrodes of the object to be tested device 10, and the object to be tested 220 A portion of the middle electrode is suspended, and a constant current is applied to the object to be tested 220 through the two outer electrodes. The object 220 is self-heated by the current and reaches a thermal equilibrium after a period of time. 0982030438-0 098117906 Form No. A0101 Page 13 / Total 36 Page 201042251 [0028] [0032] Step S104, obtaining the center point 0 and any end point of the suspended portion of the object to be tested 220, or Raman The characteristic peak frequency value of the spectrum, and compares the difference between the characteristic peak frequency value of the center point 悬 of the suspended portion of the object 220 and the Raman spectrum of either end point or. Step S105 'Acquiring the thermal power transmitted along the axial portion of the suspended portion of the object to be tested 220, step S106, using the measured object 220 to vacate a portion of the central point 〇 with the characteristic peak frequency value of any end point or 1 ^ Raman spectrum The difference between the center point of the suspended portion of the measured object 220 and the temperature difference of any of the terminals ^ or ^ is obtained; Step S107, according to the temperature difference, geometric size and heat of the center point 悬 of the object to be tested 220 and any end point ^ or ^ The thermal conductivity of the measured object 22 is calculated. - In step S101, the device to be tested 10 includes a substrate lu, a first carrier 114, a second carrier 115, a first insulating layer 112, a second insulating layer 113, and a first electrode. 116, a second electrode 117, a third electrode 118 and a fourth electrode 119. The first carrier 114 and the first carrier 115 are spaced apart from each other on the surface of the substrate 111. In this embodiment, the first carrier 114 and the second carrier 115 are arranged side by side on the surface of the substrate. The first insulating layer 112 is disposed on a surface of the first carrier 114. The second insulating layer 113 is disposed on the surface of the second carrier 115. In this embodiment, the first carrier 114, the second carrier 115, and the substrate 111 are integrally formed. The four electrodes are spaced apart, and the object to be tested 220 is in contact with the four electrodes, and a portion of the object to be tested 220 between the two electrodes is suspended. In the present embodiment, the first electrode 116 and the second electrode 117 are arranged side by side at the same time. 098117906 Form No. A0101 Page 14/36 Page 0982030438-0 201042251 On the surface of the first insulating layer 112. The third electrode 118 and the fourth electrode 119 are disposed side by side on the surface of the second insulating layer 113. [0033] In step S102, the geometric shape of the object to be detected 220 to be acquired is the length of the suspended portion of the object to be tested 220 and the cross-sectional area of the object to be tested 220. Wherein, the length of the suspended portion of the object to be tested 220

AL Ο ο is the distance between the second electrode 117 and the third electrode 118 of the device to be placed 10 . In this embodiment, the cross-section of the single-walled carbon nanotube is a circular ring, and the cross-section of the ring is calculated as S=tt (2R-b)b, where R is a single-walled carbon nanotube. The diameter of b is the wall thickness of a single-walled carbon nanotube. However, for a single-walled carbon nanotube, b is approximately a constant, b = 0.34 nm. Therefore, it is only necessary to obtain the length and outer diameter of the suspended portion of the single-walled carbon nanotube. In the embodiment, the method for obtaining the length and the outer diameter of the single-walled carbon nanotube includes the following steps: providing a device to be placed 10 with a carbon nanotube; and recording the atomic force of the carbon nanotube by an atomic force microscope Microscopic photographs, so that the suspended portion of the carbon nanotubes are all clearly visible in the photograph; scanning electron micrographs of the carbon nanotubes are taken by scanning electron microscopy, so that the suspended portions of the carbon nanotubes are all clearly visible in the photograph; Measure the outer diameter of the carbon nanotube in the atomic force microscope photograph of the carbon nanotube and calculate the outer diameter R of the carbon nanotube by using the scale of the photograph; measure the suspended portion of the carbon nanotube in the scanning electron microscope photograph of the carbon nanotube Length and use the scale of the photo to obtain the length of the suspended portion of the carbon nanotube

AL. 8纳米。 The outer diameter of the carbon nanotubes is 30 microns 098117906, the outer diameter of the carbon nanotubes is 1. 8 nanometers. Therefore, the cross section of the carbon nanotubes Form No. A0101 Page 15 of 36 0982030438-0 201042251 Product ^ = — i?) & = 1.1084Jr Square nanometer. [0034] In step S13, one end of the object 22 is placed on the surface of the first electrode 116 and the second electrode 117, and the other end is placed on the third electrode 118 and the fourth electrode. u 9 surface. It is also to be noted that when the object to be tested 220 is placed on the object to be tested 1 , the two points in contact with the first electrode 117 and the second electrode 18 become the object to be tested 220 . The two ends of the suspended portion. A current is input to the object to be tested 220 through the first electrode 116 and the fourth electrode 119. The measured object 22 starts to self-heat under the action of current and reaches after a period of time. The thermal equilibrium "the temperature of the measured object 220 reaches a stable temperature and distribution at each point of the measured object 2 2 0, that is, the intermediate temperature is still, both sides Low temperature. In the embodiment, a single single-walled carbon nanotube is disposed on the surface of the four electrodes of the device to be tested, and one end of the single-walled carbon nanotube is located at the top of the device to be tested. One electrode U6 and the second electrode 117 have the other end located at the third electrode 118 and the fourth electrode 220 of the device to be placed. The object 220 is located at a portion of the second electrode η? and the third electrode 118 is suspended. In this embodiment, the single-walled carbon nanotubes are perpendicular to the four electrodes of the device 10 to be tested. In this embodiment, as shown in FIG. 5, a flow chart of a method for preparing a single single-walled carbon nanotube on the surface of the four electrodes of the device to be tested 10 includes the following steps: [0035] Step S2 01, providing a cerium oxide substrate on the side of the first object 116 adjacent to the first electrode 116 or adjacent to the fourth electrode 119, and 098117906 Form No. 1010101 Page 16/36 pages 0992030438- 0 201042251 [0036] The two are placed in a reaction chamber. In step S202, a concentration of 10 is provided as a catalyst precursor. Since the concentration of the ferric chloride solution in the mole/liter of the iron chloride solution is low, it is ensured that a single carbon nanotube is grown on the surface of the four electrodes. In this embodiment, the carbon nanotubes grown on the substrate are single-walled carbon nanotubes. [0037] [0040] [0040] Step S203, heating the above-mentioned gasification solution to 95 (rc) Forming a catalyst gas with a mixed gas of hydrogen and helium and introducing the catalyst gas into the reaction chamber at a rate of 6 〇 2 〇〇 cubic cents per minute. Step S204, introducing hydrogen gas and methane as a carbon source gas mixture gas, Therefore, the electric carbon nanotubes of the device 10 are placed on the object to be tested. When the carbon nanotubes are rooted on the object placing device 10, the carbon nanotubes can be controlled by controlling the flow direction of the source gas. Pour on the surface of the four electrodes of the device to be placed 10. Since there is no other support around the single carbon nanotube, it is easy to dump under the action of the carbon source; The method of disposing the carbon nanotubes on the surface of the four electrodes of the analyte placing device 10 may be to directly place the prepared single-walled carbon nanotubes on the surface of the four electrodes of the device to be tested 10 . In S104, please refer to FIG. 6 , and obtain the center point 0 of the suspended portion of the measured object 220 and any The method for the characteristic peak frequency value of the Raman spectrum of the endpoint 1^ or 1^ includes the following steps shown in FIG. 6: Step S301, placing the object placement device 10 and the measuring circuit on which the object to be tested 220 is placed A vacuum chamber body 230 and the vacuum chamber body 098117906 form number A0101 page/36 pages 0982030438-0 [0041] 201042251 230 vacuum, so that the object placement device 10 and the object under test 220 are in a vacuum state The measured object 220 reaches a thermal equilibrium after the current is self-heated for a period of time. [0042] Step S302 'Immediately irradiate the center point 0 and any end point of the suspended object by the Raman laser, or obtain the measured object The peak frequency value of the Raman spectral characteristic of the center point 220 of the suspended portion of 220 and any end point or y. The measurement of the center point 〇 of the suspended portion of the object 22 〇 and the measurement of either end point L 丨 or L 2 are performed multiple times ' Performing three or more measurements, taking the average of the number of measurements. The peak value of the Raman spectral characteristic of the center point of the suspended portion of the measured object 220 and any endpoint 1^ or 1^ is at least three times. The average of the results obtained was measured. The characteristic peak frequency value to be obtained varies according to the material of the object to be tested 220. The characteristic peak frequency value required for the carbon nanotube is the peak frequency value of the G. The center point 0 of the suspended portion of the carbon nanotube is obtained. The Raman spectrum of either end 1^ or 1^, the Raman spectrum consists of a plurality of peaks, where the highest peak is its G peak. See Figure 3, the single-walled carbon nanotubes are suspended at the center point of Raman. The Raman frequency value corresponding to the G peak of the spectrum is 1567. 6αη_1, and the L peak of the Raman spectrum of 1 or L at either end corresponds to 1 L. Raman frequency system 1577. 7 cm_1. [0043] In step S105, a current flows from the first electrode 116 into the object to be tested 220 in the object to be placed, and flows out through the fourth electrode 119. Since the portion of the object to be tested 220 is located between the second electrode in and the third electrode 118, the voltage U of the suspended portion of the object to be tested 220 can be measured by connecting the voltmeter to the second electrode 117 and the third electrode 118. Under the action of the current I, the temperature of the object to be tested 220 gradually increases. The heat generated by the heating of the measured object 2 2 0 is mainly conducted to the both sides along the center point 0 of the suspended portion of the material. After a period of time, the points on the suspended portion of the object to be tested 220 have a stable temperature. 098117906 Form No. A0101 Page 18 of 36 0982030438-0 201042251 Distribution, that is, the intermediate temperature is high and the temperature on both sides is low. The measured object 2 2 〇 vacant part The heating power satisfies the relationship: P = UI. The heating power of the suspended portion of the object to be tested 220 is equal to the thermal power conducted along the suspended portion of the object to be tested 220. In this embodiment, the method for obtaining the thermal power transmitted along the axial direction of the carbon nanotube comprises the steps of: reading the value I of the current meter connected to the first electrode 116 and the fourth electrode 119, I is 0.298 microamperes; Taking the value of the voltmeter connected to the second electrode 117 and the third electrode 118, u, is 1. 175 volts; calculating the thermal power of the carbon nanotube

Ο P = U1 = 3.5 X 10_? iF 〇 [0044] In step S106, as shown in FIG. 7, the difference between the characteristic peak frequency values of the Raman spectra of the center point and the end point of the suspended portion of the measured #220 is compared. A flowchart of a method for obtaining a temperature difference between a center point of the suspended portion of the measured object 220 and any one of the end points. The method for obtaining the temperature difference ΔΤ of the whole object center point and any end point of the object to be tested 220 includes the following steps: Q [0045] Step S401, obtaining a Raman spectrum of the object to be tested 220 at a plurality of different known temperatures The characteristic peak frequency value 'obtains a plurality of data points of the peak frequency values of the Raman spectra corresponding to different temperature values. [0046] The object placement device 10 can be placed on a temperature controller. After a period of time, the temperature of the object placement device 1 and the object to be tested 220 is equal to the temperature set by the temperature controller. Therefore, the temperature of the object to be tested 1 and the temperature of the object to be tested 220 can be controlled by the temperature controller, and a plurality of different temperatures are set by the temperature controller, and the Raman of the object to be tested 220 is measured at the set temperature. The characteristic peak frequency of the spectrum. In this embodiment, please refer to 098117906 Form No. A0101 Page 19 / Total 36 Page 0982030438-0 201042251 Read Figure 8 'The plural number of repentance I prepared aunts for the early wall carbon nanotubes at different temperatures Mann spectrum G peak frequency value. [0047] / (10) 2 The plurality of data points are obtained to obtain a curve characterizing the peak frequency value of the Raman spectrum characteristic of the object to be tested 220 as a function of temperature. A functional relationship between the characteristic peak frequency and the temperature change of the measured object 220 by a mathematical method such as a nonlinear regression or spline fitting, in this embodiment, 'linearly fitting the respective data points to obtain a graph 8 Let the dotted line 'light' calculate the slope of the dotted line as K = -G· G257CHT1/ [0048] Step S403 'Compare the measured object 22{) with the center point of the suspended portion and any end point, or 1 ^ pull Mann spectrum characteristics ♦ frequency difference. In the present embodiment, the Raman spectrum was used to measure the temperature difference between the center of the suspended carbon nanotube, the point G, and the end-end point Li or . The Raman laser used for detection is focused at a certain point of the carbon nanotube. Since the spatial resolution of the Raman laser is up to 丨 micron, it is enough to measure the suspended carbon nanotubes with a floating length of 30 microns. The temperature of the point. Please refer to FIG. 3 together, and the change of the G-peak frequency value in the Raman spectrum of the center point and the one end point of the single-walled carbon nanotube suspension portion is diversified. Analysis of Fig. 3 shows the difference between the center point 悬 of the suspended portion of the single-walled carbon nanotube and the peak value of the G peak in the Raman spectrum of either end L丨 or L ΔGt-lO. lcnf1. 098117906 Step S404, using a curve that characterizes the Raman spectral characteristic peak frequency value of the measured object 220 as a function of temperature, and a center point 0 of the suspended portion of the measured object 220 and any end point, or Raman The difference between the characteristic peak frequency values of the spectra is calculated as the temperature difference between the center point 0 of the object 220 and either end point 1^ or 1^. In the present embodiment, the temperature difference between the center point of the suspended portion of the single-walled carbon nanotube and the end point 1 or 1^2 = (-10. lcm 4 (-0.0257^11^/ page 20/total 36) Page Form No. A0101 0982030438-0 201042251 [0052] [0052] [0054] [0055] Κ) = 393 。 In step S1 07, by the above measurement method, μ - * can be counted The thermal conductivity of the analyte 220 at room temperature is 2400 W/m κ. Since the solution of the present invention provides a light-reading measurement method from a branch non-contact, it is possible to avoid an object having a large heat capacity and a material to be tested. Contact, so that the temperature of the measured object remains stable, and the measurement result is more accurate. In the method for measuring the thermal conductivity of the dimensional material provided by the present invention, step sl 〇 4, step S i 0 5 and step S10 6 are steps. The order of the three steps can be step S104, step SU) 5, step S106; step S1G5, step s1〇4, step S106 or step S104, step S1〇6, step S1 (i5) Step S106 is satisfied after step S1 〇 4, and other changes can be made by those skilled in the art within the spirit of the present invention. Ϊ́11 £ .3⁄4 1 are all..·::..-.sh, of course, these changes in accordance with the spirit of the present invention should be included in the scope of the claimed invention. Figure 1 is a schematic diagram showing the structure of a functional module of a thermal conductivity measuring system according to an embodiment of the present invention. Figure 2 is a schematic structural view of a device for placing a measured object in a thermal conductivity measuring system according to an embodiment of the present invention. The Raman spectrum of the center point and any end point of the suspended portion of the test object provided by the embodiment. 098117906 Form No. A0101 Page 21 / Total 36 page 0992030438-0 [0056] 201042251 [0058] [0059] 4 is a flow chart of a method for measuring thermal conductivity of a dimensional material according to an embodiment of the present invention. FIG. 5 is a flow chart of a method for preparing a carbon nanotube as a measured object according to an embodiment of the present invention. A flowchart of a method for measuring a characteristic peak frequency value of a Raman spectrum of a center point and a single end point of a suspended portion of a test object according to an embodiment of the present invention. FIG. 7 is a method for measuring a measured object by using Raman spectroscopy according to an embodiment of the present invention. Center point and any end point of the suspended portion Flowchart of the method for temperature difference. Fig. 8 is a graph showing the relationship between the peak frequency of the Raman spectrum of the single-walled carbon nanotubes according to the embodiment of the present invention as a function of temperature. [Key element symbol description] [0062] 10 10 size 20 device acquisition module Raman spectroscopy 30 thermal power acquisition 40 characteristic peak frequency acquisition module value acquisition module comparison module 50 calculation module 60 thermal conductivity measurement 100 substrate 111 quantity system first insulation 112 second insulation 113 layer First carrier 114 second carrier 115 first electrode 116 second electrode 117 form number A0101 page 22 / total 36 page 0992030438-0 098117906 201042251 third electrode 118 fourth electrode 119 object 220 vacuum chamber 230 Ο 098117906 Form NumberΑ0101 Page 23/36 Page 0992030438-0

Claims (1)

201042251 VII. Patent application scope: 1. A one-dimensional material thermal conductivity measuring system for measuring the thermal conductivity of a measured object, wherein the one-dimensional material thermal conductivity measuring system comprises: a measured object placing device The object placement device includes at least four electrodes disposed at intervals, the object to be tested is disposed on the surface of the four electrodes, and a portion of the object to be tested located between the two electrodes is suspended, a geometric size acquisition module For obtaining the required geometric size of the measured object; a Raman light please feature the bee frequency acquisition module 'for obtaining the measured object self-heating under the action of current and reaching the thermal equilibrium, the central point of the suspended portion is Raman The characteristic peak frequency value of the spectrum is used as an initial value and a characteristic peak frequency value of any end point Raman spectrum of the suspended portion of the object; a thermal power acquisition module for obtaining thermal power transmitted along the axial direction of the suspended portion of the object to be tested; Comparing the plate 'for comparing the difference between the characteristic peak frequency values of the Raman spectrum of the center point of the suspended portion of the measured object and the arbitrary-end point of the suspended portion to obtain the center point of the object to be tested and any The temperature difference between point; A silk count mode according to the measured object to the center point of any suspended portion of a terminal '# Ho dish size and the difference between the thermal power calculating the thermal conductivity of the measured object 2 billion. The thermal conductivity measuring system according to claim 1, wherein the geometrical dimensions acquired by the acquisition module include the cross-sectional area of the measured object and the length of the eight-knife of the suspended portion of the measured object. For example, the thermal conductivity measuring system described in the patent application scope is as follows: the measured object is - the transfer material 1 7\\ yp|- ο 098117906 form number Α 0101 « 〇0982030438-0 24th I 36 pages 201042251 4 The thermal conductivity measuring system according to claim 3, wherein the measured object comprises a nanotube, a nanorod, a nanowire, a nanofiber or a nanobelt. 5. The thermal conductivity measuring system according to claim 4, wherein the object to be tested is a carbon nanotube. 6. The thermal conductivity measuring system according to claim 5, wherein the characteristic peak frequency of the Raman spectrum of the measured object is a G peak frequency value of the Raman spectrum 〇7. The thermal conductivity measuring system according to Item 6, wherein the difference between the temperature difference between the center point and the end point of the suspended portion of the carbon nanotube and the G peak frequency value of the carbon nanotube center point and any end point is The following relationship is satisfied: ΔΤ = ΚΔΟ where K is the slope of the line of the peak frequency of the Raman spectrum of the carbon nanotube with temperature; Δ T is the temperature difference between the center point of the suspended portion of the carbon nanotube and any end point; 〇 Δ G is the difference between the center point of the hollow portion of the carbon nanotube and the G peak frequency value of any of the end points. The thermal conductivity measuring system according to claim 1, wherein the object to be tested The thermal conductivity and the temperature difference between the center point and any end point of the object to be tested, the geometrical dimensions of the measured object, and the thermal power of the measured object satisfy the following relationship: where k is the thermal conductivity of the measured object; U is the measured object The voltage of the suspended portion; I is the current flowing through the measured object; △ L is the suspended object The length of the portion; Form Number A0101 098 117 906 Page 25/36 0982030438-0 201042251 s Total cross-sectional area of the measured object; △ τ is the center point of the overhang was measured and the temperature difference between either end of the point. 9. The thermal conductivity measuring system of claim 1, wherein the device to be tested comprises a substrate, a first carrier, a second carrier, a first insulating layer, and a first a second insulating layer, a first electrode, a second electrode, a third electrode, and a fourth electrode, wherein the first carrier and the second carrier are spaced apart from each other on a surface of the substrate, and the first insulating layer is disposed on the second insulating layer The surface of the first carrier, the second insulating layer is disposed on the surface of the second carrier, and the four electrodes are spaced apart. The thermal conductivity measuring system of claim 9, wherein the first electrode and the second electrode are disposed side by side on a surface of the first insulating layer, the third electrode and the fourth electrode The electrodes are spaced apart side by side on the surface of the second insulating layer. 11. A one-dimensional material thermal conductivity measuring method, comprising the steps of: providing a measured object placing device, the measuring object placing device comprising at least four electrodes arranged at intervals; obtaining a desired geometric shape of the measured object The object to be tested is placed on the surface of the four electrodes of the device to be tested, and the portion of the object to be tested is placed between the two electrodes, and a constant current is applied to the object through the two outer electrodes. The object self-heats under the action of current, and reaches the heat balance after a period of time; obtains the characteristic peak frequency value of the Raman spectrum of the center point and any end point of the suspended portion of the measured object, and compares the center point and either end of the suspended portion of the measured object The difference between the characteristic peak frequency values of the point Raman spectrum; the thermal power of the axial conduction along the suspended portion of the measured object; the special point of the Raman spectrum of the suspended point of the measured object and the end point of any of the endpoints 098117906 Form No. A0101 26 pages/total 36 pages 0982030438-0 201042251 The difference between the peak frequency values of the peaks of the measured object is obtained from the center point of the suspended portion of the measured object and the temperature difference between any of the end points, 12 . Ο 13 . 14 .Ο 1 5. Calculate the thermal conductivity of the measured object according to the temperature difference, geometric size and thermal power of the center point and any end point of the suspended portion of the measured object. The method for measuring a thermal conductivity of a dimension material according to claim 11, wherein the method for obtaining a characteristic peak frequency value of a Raman spectrum of a center point and a single end point of the suspended portion of the object to be tested includes the following steps: Place the device to be tested in which the object to be tested is placed in a vacuum chamber and evacuate the vacuum chamber so that the device to be tested and the object to be tested are in a vacuum state; The center point and any end point of the suspended portion of the object to be measured are irradiated to obtain the Raman spectral characteristic peak frequency value of the dangling center point and any end point of the object to be tested. The method for measuring thermal conductivity of a dimensional material according to claim 12, wherein the peak frequency of the Raman spectral characteristic of the center point and any end point of the suspended portion of the measured object is an average of at least three measurements. . The one-dimensional material 4 rate measuring method according to claim 11, wherein the measured object is a single-walled carbon nanotube, and the geometrical dimensions of the single-walled carbon nanotubes include the following steps: A device for placing a sample of a carbon nanotube is placed; an outer diameter of the carbon nanotube is obtained by an atomic force microscope; and a length of the suspended portion of the carbon nanotube is obtained by a scanning electron microscope. The method for measuring thermal conductivity of a dimensional material according to claim 11, wherein the calculating the difference between the characteristic peak frequency values of the Raman spectra of the center point of the suspended portion of the measured object and any of the end points is The method for measuring the temperature difference between the center point and the end point of the suspended portion of the measuring object specifically comprises the following steps: obtaining characteristic peak frequency values of the Raman spectrum of the measured object at a plurality of different temperatures to obtain a plurality of Raman spectra corresponding to different temperature values Characteristic peak frequency value 098117906 Form No. A0101 Page 27 / Total 36 page 0992030438-0 201042251 Data points; fitting the plurality of data points to obtain a function of the peak frequency value of the Raman spectrum characteristic of the measured object as a function of temperature Curve; compares the difference between the characteristic peak frequency values of the center point and any end point of the suspended portion of the measured object; and uses the curve which characterizes the peak frequency value of the Raman spectrum characteristic of the measured object as a function of temperature and the object to be suspended The difference between the characteristic peak frequency values of the Raman spectrum of the center point of any part and the end point of any part is calculated as the temperature difference between the center point and any end point of the suspended portion of the measured object. 16. The method for measuring thermal conductivity of a dimensional material according to claim 15, wherein the fitting the plurality of data points to obtain a function of the peak frequency value of the characteristic Raman spectrum of the measured object as a function of temperature The method of the curve is a mathematical method such as linear regression, nonlinear regression or spline fitting. 17. The method for measuring thermal conductivity of a dimensional material according to claim 15, wherein when the measured object is a carbon nanotube, a temperature difference between a center point of the suspended portion of the carbon nanotube and any end point The difference between the G-peak frequency value of the center point and the end point of the suspended portion of the carbon nanotube satisfies the following relationship: Δ7=ΚΔσ where κ is the Raman spectrum of the carbon nanotubes. Slope; Δ τ is the temperature difference between the center point and any end point of the suspended portion of the carbon nanotube; Δ G is the difference between the center point of the hollow portion of the carbon nanotube and the G peak frequency value of any end point .18. Method for measuring thermal conductivity of one-dimensional material of 15 items, 098117906 Form No. 1010101 Page 28/36 pages 0982030438-0 201042251 Wherein, the characteristic peak of the Raman spectrum of the measured object at a plurality of different temperatures is obtained The frequency value is controlled by the temperature controller to control the temperature of the device to be placed and the object to be tested. 19. The method for measuring thermal conductivity of a dimensional material according to claim 11, wherein the thermal conductivity of the measured object and the temperature difference between the center point of the measured object and any of the end points, the geometry of the measured object The size and the thermal power of the measured object satisfy the following relationship, where k is the thermal conductivity of the measured object; ύ U is the voltage of the suspended portion of the measured object; I is the current flowing through the measured object; Δ L is the measured object The length of the suspended portion; S is the cross-sectional area of the measured object; Δ T is the temperature difference between the center point of the suspended portion of the measured object and any end point. ❹ 098117906 Form No. A0101 Page 29 of 36 0982030438-0