JP2011247613A - Analytical method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform accurate temperature correction in a thermo-analytical method.SOLUTION: Differently from the substance of an analysis object, an internal standard sample for which a standard substance that generates a gas in the range from a normal temperature to 1000°C is added to a sample is prepared. Then, by analyzing the internal standard sample by a temperature-programmed desorption analytical method, the temperature-programmed desorption spectrum of a standard gas generated from the standard substance is acquired. Also, in the analysis of the temperature-programmed desorption analytical method, the substance of the analysis object is analyzed as well together with the analysis of the standard gas. When the substance of the analysis object is included in the sample (internal standard sample), the temperature-programmed desorption spectrum of the substance of the analysis object is also obtained together with the temperature-programmed desorption spectrum of the standard gas. Then, from the obtained temperature-programmed desorption spectrum of the standard gas, a measurement temperature generated the standard gas from the standard substance is obtained.

Description

  The present invention relates to an analysis method for analyzing a component in a solid material by a thermal analysis method such as a temperature programmed desorption analysis method.

  As a method for analyzing a gas (gas) component or a component desorbed as a gas at a high temperature among components present in a solid sample, there is a temperature programmed desorption analysis method. In the thermal desorption analysis method, a thermal desorption analyzer is used, for example, a sample is heated in a vacuum, and a gas desorbed from the sample by this heating is detected by a mass spectrometer.

  The temperature-programmed desorption analysis method is utilized as an analysis method for measuring, for example, a contaminated gas component or an adsorbed component on the surface or inside of a semiconductor material. In recent years, however, it is also used for analyzing the amount of gas components such as hydrogen in steel materials. In steel materials, the presence of hydrogen or the like often impairs mechanical properties, and analysis of the amount of hydrogen penetration is important.

The temperature programmed desorption analysis method usually increases the temperature of a solid sample at a constant rate in a vacuum (for example, about 4 × 10 ⁻⁷ Pa), desorbs from the sample at each temperature, and is released into the vacuum. The gas component is detected by a mass spectrometer such as a quadrupole mass spectrometer. In mass spectrometry, a gas desorbed (generated) by heating is ionized by an ion method such as electron impact, and the intensity of the ions is detected. In the detection of ion intensity, ions are fractionated (spectroscopic) for each mass / charge ratio, guided to a detector, and the amount of ions is measured as a current value. In the detection of ion intensity, each ion is detected as a voltage pulse, and this is amplified and counted.

  Thus, the signal obtained by mass spectrometry is the current of ions having a specific mass / charge ratio, or pulse counted, derived from a gas component. Here, since the value of the charge of the substance (ion) to be analyzed is almost 1, the mass / charge ratio may be a mass number. In thermal desorption analysis, mass analysis is performed on gas components generated in the process of raising the temperature of a sample, and the spectrum (temperature programmed desorption spectrum) in which the intensity of ions obtained by mass analysis changes with the temperature of heating. ). This temperature-programmed desorption spectrum is generally represented by a graph in which the horizontal axis represents temperature and the vertical axis represents detected signal intensity of ions.

  By analyzing the temperature-programmed desorption spectrum, it is possible to obtain knowledge about the energy required for desorbing the detected component from the sample as a gas. From this desorption energy, the existence state of the detected component in the sample can be inferred. can do. In this inference, the temperature that is the horizontal axis of the temperature programmed desorption spectrum is very important. The temperature is measured using a thermometer such as a thermocouple placed in the vicinity of the sample.To obtain the actual temperature from the measured value of the thermometer, the difference between the measured value and the actual temperature is clarified. Need to be calibrated.

N. Hirashita, et al., "Study on temperature calibration of a silicon substrate in a temperature programmed desorption analysis", J. Vac. Sci. Technol. A, vol. 19, no. 4, pp. 1255-1260, 2001 .

  As the temperature calibration method described above in the temperature programmed desorption analysis method, there are generally the following two methods.

  In the first temperature calibration method, in addition to the thermocouple A placed in the vicinity of the sample, a thermocouple B in contact with the sample is provided, and the measured value by the thermocouple B is the actual temperature of the sample. This is a method of calibrating the temperature by the difference from the measured value by A. In this method, a pseudo-standard sample having a thermally stable composition such as silicon is measured, the temperature is measured simultaneously using thermocouple A and thermocouple B, the above-described calibration is performed, and the actual sample is measured. Then, without using the thermocouple B, the measured value by the thermocouple A is calibrated to obtain the temperature of the sample.

  However, in the above-described temperature calibration method, when the thermal conductivity due to the size of the pseudo standard sample and the sample or the difference in the composition of the medium differs between the pseudo-standard sample and the sample, the measured value of the thermocouple A in the measurement of the sample is The actual temperature of the sample cannot be obtained. In actual temperature-programmed desorption analysis, it often happens that the size and thermal conductivity differ between the standard quasi-sample and the actual sample. For this reason, the above is a problem.

  The above-described problem can be solved by measuring the thermocouple B in contact with the sample. However, since the thermocouple is a metal, the method of bringing the thermocouple B into contact with the sample cannot be applied when measuring a metal sample that may form an alloy with the thermocouple metal at a high temperature. Further, the above-described calibration method is not appropriate for measurement of a sample in which it is difficult to obtain good thermal contact with the thermocouple B, such as when measuring a powder sample.

  Next, in the second temperature calibration method, a substance that generates gas at a specific temperature is measured as a temperature standard sample, and the temperature is calibrated. The specific temperature in this method is a temperature specific to a substance defined by a physical phenomenon or a chemical phenomenon. For example, a temperature defined by a chemical phenomenon called a decomposition temperature is a temperature at which a substance starts to decompose, and is a value unique to the substance. The temperature measurement value (measured temperature) is calibrated from the correspondence between the specific temperature associated with the physical and chemical properties of the temperature standard sample and the temperature measurement value by the thermocouple. This temperature calibration method often uses a plurality of temperature standard samples having different specific temperatures.

  However, even in this method, when the thermal conductivity is different between the temperature standard sample and the sample due to the difference in thickness or the composition of the medium, the actual value of the sample is determined from the measured value of the thermocouple in the sample measurement. It is difficult to obtain a temperature of In principle, in each measurement, the shape and thermal conductivity of the temperature standard sample may be matched with the sample to be measured, but the sample forms are diverse and it is realistic to match. is not.

  In addition, when a plurality of temperature standard samples having different specific temperature characteristics are used, the measurement time is long. For example, when calibration is performed using two temperature standard samples, the measurement of two temperature standard samples and the actual measurement of the sample are three times in total. In the temperature programmed desorption analysis method, as is well known, the measurement environment (sample chamber) in which the sample is placed is in a high vacuum state when performing analysis, and thus requires a lot of time. One measurement may take 2 hours or more. In addition, when the next measurement is continuously performed after the measurement is performed once, the sample chamber needs to be at room temperature (about 20 ° C.) in the stage where the next measurement is performed. In the measurement, the temperature is as high as several hundred degrees, so it usually takes about 1 hour to reduce the temperature to room temperature. Accordingly, when three measurements are performed as described above, the measurement time is approximately 3 × 3 = 9 hours, which requires a lot of time.

In addition, a method of performing temperature calibration by placing a substance for temperature calibration on a sample to be measured and performing analysis in this state has been proposed (see Non-Patent Document 1). In this technique, a material for the temperature calibration, are placed pellets of CaC ₂ O ₄ · H ₂ O in the sample temperature calibrated. In this method, it is expected that temperature calibration can be performed using the fact that a specific gas such as carbon monoxide is generated at a specific temperature from a material for temperature calibration.

  However, even in this method, the actual temperature of the sample cannot be obtained from the measured temperature value because the thermal conductivity differs depending on the difference in shape and dimensions and the difference in the composition of the medium between the substance and the sample. Have difficulty.

  In addition, placing a bulk material close to the sample, such as a pellet, on the sample is placed on the sample from the position of the thermocouple used to measure the temperature of the sample (usually at the bottom of the sample). The distance between the gas generation position from the pellet (usually the upper part of the pellet) is increased. For this reason, a large temperature difference is caused between the temperature measurement point and the gas generation point, and accurate temperature calibration becomes more difficult. Also, since a bulk material is used as the temperature calibration material, it is impossible to make the thermal conductivity almost the same as the sample even though the thickness and the like can be made almost the same as the sample. It is.

  As described above, thermal analysis methods such as temperature programmed desorption analysis have a problem that accurate temperature calibration cannot be easily performed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to facilitate accurate temperature calibration by a thermal analysis method.

  The analysis method according to the present invention is an analysis method for analyzing a substance to be analyzed that is expected to be contained in a sample by a thermal analysis method, and is an index that generates a gas in the range of room temperature to 1000 ° C., unlike the substance to be analyzed. The first step of preparing the internal standard sample with the substance added to the sample and the internal standard sample are analyzed by thermal analysis, thereby obtaining a measurement result indicating the change in detected intensity with respect to temperature in the indicator gas generated from the indicator substance And a third step for obtaining a measurement temperature at which the indicator gas is generated from the indicator substance from the measurement result, and a reference temperature and a measurement temperature at which the indicator gas is generated from the indicator substance in the analysis environment by thermal analysis. And at least a fourth step of calibrating the heating temperature measured in the thermal analysis of the substance to be analyzed in the internal standard sample.

  In the above analysis method, in the first step, a plurality of different indicator substances are added to the sample to prepare an internal standard sample, and in the second step, measurement results of each indicator gas generated from the plurality of indicator substances are obtained. In the third step, the respective measured temperatures at which the indicator gases are generated from the plurality of indicator substances are obtained, and in the fourth step, the respective reference temperatures at which the indicator gases are generated from the plurality of indicator substances in the analysis environment by thermal analysis. The measured temperature may be used to calibrate the heating temperature.

  In the above analysis method, the thermal analysis method is, for example, a temperature programmed desorption analysis method, and the measurement result is a temperature programmed desorption spectrum.

  As described above, according to the present invention, thermal analysis is performed as an internal standard sample in which an indicator substance that generates gas in the range of room temperature to 1000 ° C. is added to the sample. It is possible to obtain an excellent effect that the calibration can be easily performed.

FIG. 1 is a flowchart for explaining an analysis method according to an embodiment of the present invention. FIG. 2 is a configuration diagram showing the configuration of the internal standard sample. FIG. 3 is a configuration diagram showing the configuration of the internal standard sample. FIG. 4 is a characteristic diagram showing an example of a temperature programmed desorption spectrum. FIG. 5 is a characteristic diagram showing the relationship between time and temperature in measurement. FIG. 6 is a flowchart for explaining temperature calibration in the analysis method according to the embodiment of the present invention. FIG. 7 is a configuration diagram illustrating a configuration example of a temperature programmed desorption analyzer.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a flowchart for explaining an analysis method according to an embodiment of the present invention. In this analysis method, first, in step S101, an internal standard sample is prepared by adding an indicator material (internal standard material) that generates gas in the range of room temperature to 1000 ° C., unlike a substance to be analyzed. For example, the indicator substance may be added (added) to the sample by coating or injection.

  Next, in step S102, the measurement result of the indicator gas generated from the indicator substance is obtained by analyzing the internal standard sample by a thermal analysis method such as a temperature programmed desorption analysis method. In the case of temperature programmed desorption analysis, a temperature programmed desorption spectrum can be obtained as a measurement result. In this analysis, analysis (measurement) of the substance to be analyzed is performed together with analysis of the indicator gas. If the sample (internal standard sample) contains a substance in the analysis target, the measurement result (for example, temperature-programmed desorption spectrum) of the target substance can be obtained together with the measurement result of the index gas (for example, temperature-programmed desorption spectrum). .

  Next, in step S103, the measured temperature at which the indicator gas is generated from the indicator substance is obtained from the obtained measurement result of the indicator gas. For example, in the temperature programmed desorption analysis, the time point at which the indicator gas is generated can be determined from the temperature-programmed desorption spectrum of the index gas, and the temperature (measured temperature) measured at this time point may be obtained.

  Next, in step S104, measurement is performed by thermal analysis of the substance to be analyzed in the internal standard sample using the reference temperature and measurement temperature at which the indicator gas is generated from the indicator substance in the environment of analysis by thermal analysis. Calibrate the heating temperature (measured temperature). The reference temperature at which the indicator gas is generated (starts to be generated) from the indicator substance is known, and the measured temperature can be calibrated by using the known reference temperature.

  Next, production of an internal standard sample will be described. For example, as shown in FIG. 2, a region 202 to which an indicator substance is added (added) is formed on a thin flat plate-like sample 201 having a rectangular shape in plan view. The region 202 is a region where an indicator substance is added by coating, injection, or the like. As illustrated in FIG. 2, the region 202 may be formed on a part of the surface of the sample 201 or may be formed on the entire surface of the sample 201. A plurality of regions made of different indicator substances may be provided.

  Although the temperature unevenness in the sample 201 affects the width of the temperature-programmed desorption spectrum as a measurement result, the temperature unevenness can be reduced by reducing the plate thickness of the sample 201 and reducing the surface area. However, reducing the size of the sample 201 has a limit because it leads to reducing the signal intensity obtained by a thermal analysis method such as thermal desorption analysis. In the case where a certain degree of temperature unevenness is allowed, it is desirable that the temperature of the region 202 represents the temperature of the entire sample 201.

  Next, the indicator substance will be described. The indicator substance only needs to have a property of generating a vapor pressure at a temperature higher than room temperature. In thermal analysis methods such as temperature programmed desorption analysis, the upper limit of the substantial heating temperature is 1000 ° C., and the upper limit of the temperature at which the vapor pressure in the indicator substance is generated may be 1000 ° C. What is necessary is just to have a property which produces a vapor pressure in the temperature range of room temperature-1000 degreeC.

  Examples of substances that are relatively stable solids at room temperature, have almost no vapor pressure, and melt to have vapor pressure in the temperature range of room temperature to 1000 ° C. include zinc, indium, lead, tin There are low melting point metals such as. For example, when zinc is melted at 420 ° C., a vapor pressure is generated and a part thereof is vaporized. As a method of adding these low melting point metals to the sample, ion implantation which is a kind of implantation may be used. For example, ion implantation may be performed by accelerating the above-described monovalent ions of the low melting point metal as ion species.

  In addition, examples of substances that sublime in the temperature range of room temperature to 1000 ° C. include orthorhombic sulfur and arsenic.

  Further, the indicator substance may be a substance having a property of decomposing and generating a gas in a temperature range of room temperature to 1000 ° C. Examples of such materials include metal salt hydrates, carbonates, metal carbonyls, oxalates, and peroxides.

  A gas that is an index of temperature generated from the indicator substance (hereinafter referred to as an indicator gas) needs to have a mass number different from that of the substance to be measured. In mass spectrometry, the mass number of fragments (ions) generated by decomposing the indicator gas by electron impact or the like needs to be different from the mass number of the substance to be measured.

  In addition, when the indicator substance is added to the sample by coating, the coating liquid containing the indicator substance contains a solvent and a binder. When such a solvent or binder generates gas by heat, the mass number of the generated gas and the mass number of the fragment generated when the generated gas is decomposed by electron impact or the like are both different from the substance to be measured. Need to be.

  For example, when the sample is steel, and the substance to be measured is hydrogen (mass number 2), carbonate, metal carbonyl, oxalate, peroxide, etc. can be selected as the indicator substance. Gases generated by decomposition of these substances by heating are, in order, carbon dioxide, carbon monoxide, carbon monoxide, and oxygen. Carbon dioxide has a main mass number of 44, and the main fragments produced by decomposition have a mass number of 12 and 16. Carbon monoxide has a main mass number of 28, and main fragments produced by decomposition have a mass number of 12 and 16). In addition, oxygen has a main mass number of 32, and a main fragment generated by decomposition has a mass number of 16. These differ in mass number from hydrogen and do not affect the measurement of hydrogen.

  By the way, the temperature distribution (temperature unevenness) in a sample can be evaluated by using two indicator substances composed of isotopes having different mass numbers. For example, as shown in FIG. 3, in addition to the region 202, a region 203 to which an indicator material composed of an isotope having a mass number different from that of the indicator material added to the region 202 is added to the sample 201. . Similarly to the region 202, the region 203 is a region to which another indicator substance is added by coating, injection, or the like.

  For example, nickel carbonyl may be used as the indicator substance. The oxygen constituting nickel carbonyl has isotopes having a mass number of 16 and a mass number of 18. Therefore, the region 202 is formed of nickel carbonyl composed of oxygen having a mass number of 16, and the region 203 is formed of nickel carbonyl composed of oxygen having a mass number of 18. If the sample 201 (internal standard sample) formed in this way is analyzed by a thermal analysis method (for example, temperature programmed desorption analysis), carbon monoxide having a mass number of 28 is generated as an indicator gas from the region 202, and from the region 203. Carbon monoxide with a mass number of 30 is generated as an indicator gas.

  Since carbon monoxide having a mass number of 28 and carbon monoxide having a mass number of 30 have different mass numbers, they can be analyzed as different substances, and measurement results (temperature-programmed desorption spectra) are obtained. The presence or absence of the temperature distribution can be evaluated by comparing the two measurement results (temperature-programmed desorption spectra) thus obtained. For example, as a result of comparing two temperature rising spectra, if it can be determined that there is no difference between the time when carbon monoxide with a mass number of 28 is generated and the time when carbon monoxide with a mass number of 30 is generated, the regions 202 and 203 It can be evaluated that there is no temperature distribution in between. When there are three or more isotopes, three or more indicator substances composed of isotopes having different mass numbers may be used.

  Next, the case where steel is used as a sample and hydrogen contained in the steel is analyzed will be described as an example. In this case, zinc (Zn) can be used as the indicator substance. Hydrogen to be measured has a mass number of 2. The indicator substance Zn has a stable isotope mass number of 64 and melts at 420 ° C. to generate a vapor pressure. Therefore, in the temperature programmed desorption analysis, the mass number 2 and the mass number 64 are set in the measurement channel for analysis.

  When temperature programmed desorption analysis is performed under these conditions, two temperature programmed desorption spectra as shown in FIG. 4 are obtained. FIG. 4A is a temperature programmed desorption spectrum obtained with a channel having a mass number of 2, which is a temperature programmed desorption spectrum of hydrogen. FIG. 4B is a temperature programmed desorption spectrum obtained with a channel having a mass number of 64, which is a temperature programmed desorption spectrum of Zn.

  In FIG. 4, R is a measured temperature when heating in the temperature programmed desorption analysis is started. At this time, the temperature of the sample is room temperature (normal temperature). At the measurement temperature R, the vicinity of the sample including the sample and the thermocouple for heating the sample is in a thermal equilibrium state at room temperature, and each temperature can be equal to the room temperature. The normal temperature is, for example, a temperature in the range of 20 ° C. ± 15 ° C. as in Japanese Industrial Standard.

  In FIG. 4, M is a measured temperature at which the signal intensity of the temperature programmed desorption spectrum of Zn is recognized to have increased with a significant difference from the background intensity. The temperature can be the temperature at which vapor pressure begins to occur. As described above, since the temperature at which the vapor pressure of Zn starts to occur is 420 ° C., the measurement temperature M can be set to a state in which the temperature of the sample is 420 ° C. (index temperature).

  As described above, the actual sample temperature when the measured temperature R obtained from the temperature programmed desorption spectrum is measured, the actual sample temperature when the measured temperature M is measured, and the measured temperature by the thermocouple measurement By comparing R and the measured temperature M, the measured temperature by the thermocouple can be calibrated.

  For example, in the above-described temperature programmed desorption analysis, when the sample is heated under a constant temperature rise condition, the change in the sample temperature from the measured temperature R to the measured temperature M is (the measured temperature R is It is a linear function of time indicated by a straight line passing through (measured time, room temperature) and (time t1, when the measured temperature M is measured, index temperature).

Here, since the vapor of Zn can be generated at the time t ₁ when the measured temperature M is measured, the time change of the actual temperature in the sample is as shown in (b) of FIG. It is indicated by a straight line passing through time 0, room temperature T _R ) and (time t ₁ , index temperature T _M ). On the other hand, when the temperature at the time point t ₁ measured with the thermocouple arranged near the sample is T ₁ , the time change of the temperature (measured temperature) measured with the thermocouple is shown in FIG. As shown in FIG. 3, the time is indicated by a straight line passing through (time 0, room temperature T _R ) and (time t ₁ , measured temperature T ₁ ).

If the analysis result is obtained as described above, calibration can be performed as shown in the flowchart of FIG. First, in step S601, from the time t ₁ when the indicator gas is generated, the room temperature T _R at the start of analysis, and the indicator temperature T _{M at which the} indicator gas is generated, the temperature T of the sample is calculated as shown in the following equation (1). The equation shown as a function of time is obtained.

Next, in step S602, the time t ₁ indicator gas evolved, from room temperature T _R of the measured measured temperature T _1, and analyzed at the start at time t _1, the thermocouple as shown in the following equation (2) An equation is obtained in which the measured temperature T ′ measured in is shown as a function of time.

  If each equation is obtained as described above, in step S603, an equation for calibration to obtain T by correcting T 'is obtained as shown in the following equation (3).

  Finally, the horizontal axis (temperature axis) of the temperature programmed desorption spectrum shown in (a) of FIG. 4 can be calibrated by using Equation (3), which is an equation for calibration obtained.

In general, the above-described linear approximation is sufficient. However, there are cases where the temperature rise conditions in the analysis are not constant, and the temperature changes with time slightly off the straight line. In this case, different mass number and Zn, the other indicator substance to be T _M different index temperature (T _D), an internal standard sample prepared by adding to the sample with Zn, in the internal standard sample The temperature-programmed desorption spectrum may be measured (temperature-programmed desorption analysis). In this case, an equation of a curve passing through three points of the room temperature T _R at the start of analysis, the index temperature T _M by Zn at the measurement temperature M, and the index temperature T _D by another index substance at the time D is obtained. If the calibration is performed using the, higher accuracy can be realized.

  Next, a temperature-programmed desorption analyzer that performs temperature-programmed desorption analysis will be described. The temperature-programmed desorption analysis can be performed using, for example, a temperature-programmed desorption analyzer shown in FIG. In this apparatus, a sample 702 placed in a vacuum chamber 701 is placed on a heat conducting rod 704 that is directly connected to an infrared lamp 703. The sample mounting portion of the heat conducting rod 704 is disposed inside the vacuum chamber 701. The vacuum chamber 701 is connected to a vacuum exhaust mechanism (not shown). Note that the sample 702 is an internal standard sample to which an indicator substance is added as described above.

  In this apparatus, a thermocouple monitor 706 indicates a temperature measurement value by a thermocouple 705 disposed in the immediate vicinity of the sample 702. The heating temperature by the infrared lamp 703 is controlled by the temperature controller 707 so that the temperature measurement value measured by the thermocouple 705 matches the set value. If this control is performed using the result of calibration obtained as described above, more accurate temperature control can be performed. The setting of the temperature controller 707 can be performed by the computer 713.

  In the vacuum chamber 701 that has been evacuated, a part of the gas component that is desorbed and released from the heated sample 702 is ionized in the ionization chamber 708 by an ion method such as electron impact. The gas components ionized in this manner are sorted by mass / charge ratio (simply referred to as mass number) by the mass spectrometer 709, guided to the detector 710, and the amount of the ionized gas components is measured as a current value. Is done. The detector 710 may detect each ionized gas component as a voltage pulse, amplify it, and count it.

  It is sufficient that at least two mass numbers, that is, the mass number of the gas to be measured and the mass number of the indicator gas, are set in the measurement channel and can be measured. According to this apparatus, a current (or counted pulse) of ions having a specific mass number derived from a gas component of interest is obtained as a signal, a graph 711 in which the horizontal axis is temperature and the vertical axis is signal intensity, It is displayed on the display unit 712 of the computer 713. A graph 711 shows a temperature rise spectrum. The temperature desorption spectrum data can be stored in a recording device (not shown) inside the computer 713. Further, the temperature-programmed desorption spectrum data can be stored in a storage medium (not shown) using magnetism or semiconductor memory, if necessary.

  It should be noted that the present invention is not limited to the embodiment described above, and that many modifications can be implemented by those having ordinary knowledge in the art within the technical idea of the present invention. It is obvious. For example, when using different indicator materials such as different mass numbers, obtain the measurement results of each indicator gas generated from the indicator materials, and obtain the measured temperatures at which the indicator gas was generated from the indicator materials The heating temperature may be calibrated using the reference temperature and the measured temperature at which the indicator gas is generated from the plurality of indicator substances in the environment of the analysis by the thermal analysis method.

  For example, although the temperature programmed desorption analysis method has been described above as an example, the present invention is not limited to this. The present invention can also be applied to other thermal analysis methods that measure the physical properties of a substance (or reaction product) as a function of temperature (or time) while changing the temperature of the substance to be measured according to a certain program. Needless to say.

  201 ... sample, 202 ... region.

Claims (3)

In an analysis method for analyzing a substance to be analyzed that is expected to be contained in a sample by thermal analysis,
Unlike the substance to be analyzed, a first step of preparing an internal standard sample in which an indicator substance that generates gas in the range of room temperature to 1000 ° C. is added to the sample;
A second step of obtaining a measurement result indicating a change in detected intensity with respect to temperature in the indicator gas generated from the indicator substance by analyzing the internal standard sample by thermal analysis;
From the measurement result, a third step for obtaining a measured temperature at which the indicator gas is generated from the indicator substance;
The heating temperature measured in the analysis of the substance to be analyzed in the internal standard sample using the reference temperature at which the indicator gas is generated from the indicator substance and the measurement temperature in the analysis environment by the thermal analysis method And a fourth step of calibrating the method. The analysis method according to claim 1,
In the first step, an internal standard sample is prepared by adding a plurality of different indicator substances to the sample,
In the second step, a measurement result of each indicator gas generated from the plurality of indicator substances is obtained,
In the third step, each measured temperature at which the indicator gas is generated from the plurality of indicator substances is obtained,
In the fourth step, the heating temperature is calibrated using each reference temperature and the measured temperature at which the indicator gas is generated from a plurality of the indicator substances in an environment of analysis by the thermal analysis method. Analysis method. The analysis method according to claim 1 or 2,
The thermal analysis method is a temperature programmed desorption analysis method, and the measurement result is a temperature programmed desorption spectrum.

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