JP5482599B2 - Laser ablation mass spectrometer - Google Patents

Description

  The present invention relates to a laser ablation mass spectrometer, and more particularly to a laser ablation mass spectrometer characterized by an ablation chamber that vaporizes a solid sample by irradiating the laser with a carrier gas and introduces the vaporized sample into an ICP-MS apparatus together with a carrier gas. It is.

  The inductively coupled plasma mass spectrometry (ICP-MS) method is currently attracting attention as a technique that enables ultra-trace elements with high sensitivity and simultaneous quantitative analysis of multiple elements. Of particular interest is the laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method, which applies the laser ablation (LA) method, which enables direct local analysis of solid samples, in the fields of geology and material chemistry. It is used in.

  The LA-ICP-MS system used when applying this LA-ICP-MS method is an ablation chamber that contains a solid sample, and a laser that irradiates the surface of this solid sample with a high-intensity laser such as an Nd-YAG laser. An LA device composed of a transmitter, and an ICP-MS device that performs mass spectrometry by introducing sample aerosol (sample fine particles) in which a solid sample is thermally vaporized by laser in an ablation chamber together with a carrier gas , Is roughly composed of.

  This LA-ICP-MS method is used in various fields. In the above-mentioned LA-ICP-MS system, a high percentage of sample aerosol produced by ablating a solid sample is introduced into the ICP-MS system. Is one of the resolution issues in this field. More specifically, in LA-ICP-MS analysis, the main forming element of the area is identified from mass analysis for each area of the solid sample, and mapping analysis is performed on the entire solid sample.

  In the conventional LA-ICP-MS apparatus used for this analysis, the size of the ablation chamber that contains the solid sample and is irradiated with the laser is often large, so that the sample aerosol and carrier gas diffuse. There is a problem that the sample aerosol is not smoothly provided in the ICP-MS apparatus in fluid communication with the ablation chamber.

  If it took more time than necessary to provide the sample aerosol to the ICP-MS system, the mass analysis was performed prior to the mass analysis of an area in the ICP-MS system. The contents of mass analysis in other areas are affected, and precise mass analysis and mapping analysis cannot be performed.

  In the conventional LA-ICP-MS system, ablation is performed in the ablation chamber, mass analysis is performed in the ICP-MS system in fluid communication with the ablation chamber, and then the residual sample aerosol in the ablation chamber is removed from the ICP- It is discharged to the MS device and the inside of the ablation chamber is cleaned, and the next ablation is executed. In this device, the ablation chamber and the ICP-MS device form a sealed space while fluidly communicating with each other, and are not in fluid communication with the outside air. Therefore, it is difficult to clean the inside of the ablation chamber sufficiently. Is one of the obstacles to effective mapping analysis.

  Therefore, the development of a LA-ICP-MS device that can provide a carrier gas containing sample aerosol smoothly from the ablation chamber to the ICP-MS device and has a high cleaning effect in the ablation chamber is an urgent issue in this technical field. .

  Incidentally, Patent Document 1 discloses an LA-ICP-MS method and apparatus applicable to not only a solid sample but also a liquid sample. This is a method and apparatus that enables laser ablation of a liquid sample by freeze-solidifying the liquid sample into a solid sample. By allowing the sample holder constituting the apparatus to be cooled at a low temperature, the sample temperature can be maintained at a low temperature and ablation by laser light can be performed.

  However, the LA-ICP-MS apparatus disclosed in Patent Document 1 is characterized in that the sample holder can be cooled at a low temperature, but the other apparatus configuration is substantially the same as the conventional apparatus described above, Therefore, there is no guarantee that the sample aerosol is smoothly introduced into the ICP-MS apparatus from the ablation chamber or that the sample aerosol remaining in the ablation chamber is effectively washed.

JP-A-11-51904

  The present invention has been made in view of the problems described above, and can provide a sample aerosol obtained by ablating a solid sample smoothly from the ablation chamber to the ICP-MS apparatus without taking time, and the ablation chamber. It is an object of the present invention to provide a laser ablation mass spectrometer that is excellent in cleaning performance and can perform precise mass spectrometry and mapping analysis.

  In order to achieve the above object, a laser ablation mass spectrometer according to the present invention comprises a laser ablation device (LA device) comprising a laser transmitter and an ablation chamber containing a solid sample, and is in fluid communication with the ablation chamber for vaporization. In a laser ablation mass spectrometer comprising an inductively coupled plasma mass spectrometer (ICP-MS apparatus) in which a sample aerosol is introduced together with a carrier gas and mass analysis of the sample aerosol is performed, the ablation chamber is formed from an outer tube and an inner tube. The inner pipe is a first flow path, and the space between the inner pipe and the outer pipe is a second flow path. The first pipe is located in the middle of the inner pipe. And an ICP-MS device in fluid communication with the ablation passage. The chamber is fixed in a posture with a gap between it and the solid sample, sample aerosol is generated by laser ablation, and a carrier gas is introduced into the first channel and the second channel in the direction toward the solid sample. The carrier gas flowing in the second flow path is reflected by the surface of the solid sample and guided to the first flow path, and the sample aerosol is guided to the introduction path.

  In the laser ablation mass spectrometer of the present invention, a double-pipe structure pipe line is applied to the ablation chamber of the LA apparatus constituting the apparatus, and the ablation chamber is fixed in a posture in which a gap is provided between the solid sample and the ablation chamber. By performing ablation to generate a sample aerosol, the carrier gas is allowed to flow in both the inner tube (first flow channel) and the space between the inner tube and the outer tube (second flow channel). The carrier gas flowing through the channel is reflected on the surface of the solid sample and guided to the first channel, and the introduced carrier gas smoothly provides the sample aerosol to the introduction channel in fluid communication with the ICP-MS device. It plays.

  Here, since a gap is provided between the ablation chamber and the solid sample, the ablation chamber is open to the outside air through this gap. However, the carrier gas flowing through the second flow path forms a barrier when the outside air tries to enter the ablation chamber by the carrier gas flowing through the second flow path, and the outside air enters the ablation chamber and the sample Contamination of aerosol can be suppressed.

  In this way, by applying the pipe form of the double pipe structure and forming a gap with the solid sample, the carrier gas forms an upward flow in the inner pipe and the sample aerosol to the introduction path is formed. Because it can guarantee the provision, the inner tube and the space between the outer tube and the inner tube can be set as small as possible, and even with a small amount (or slow speed) of the carrier gas, the sample aerosol can be smoothly transferred to the ICP- It can be provided to the MS device.

  In addition, when the provision of the sample aerosol to the ICP-MS device is completed, the sample aerosol remaining in the ablation chamber is exhausted through the gap between the ablation chamber and the solid sample by stopping the flow of the carrier gas. Can do.

  As another embodiment of the laser ablation mass spectrometer according to the present invention, the ablation chamber is composed of a triple tube structure having a separate outer tube on the outer side of the outer tube. A space between the outer tubes is a third flow path, and the ablation chamber is fixed in a posture with a gap between the solid sample and a sample aerosol is generated by laser ablation. The carrier gas is introduced into the second flow path and the third flow path in the direction toward the solid sample, and the carrier gas flowing through the second flow path and the third flow path is reflected on the surface of the solid sample to be first. There is a form in which the sample aerosol is guided to the introduction channel and guided to the introduction channel.

  By adopting the triple tube structure, the effect of suppressing the entry of outside air and the effect of suppressing the leakage of the sample aerosol to the outside can be further enhanced. Further, a quadruple tube structure or the like may be applied.

  In a preferred embodiment of the laser ablation mass spectrometer according to the present invention, the outer tube or the separate outer tube is provided with a flange projecting outward from an end surface facing the solid sample.

  In the case of a double-pipe structure, the outer tube is provided, and in the case of a triple-pipe structure, a separate outer tube (outermost pipe line) is provided with a flange projecting outward on the end surface facing the solid sample. As a result, the distance until the sample aerosol enters through the gap under the flange or the sample aerosol leaks to the outside through the gap under the flange is increased, and the pressure loss is increased. Thus, the carrier gas and the sample aerosol are difficult to leak to the outside. This means that the sample aerosol can be introduced into the ICP-MS apparatus through the introduction path with as little carrier gas as possible or with as low a carrier gas as possible.

  In a preferred embodiment of the laser ablation mass spectrometer according to the present invention, the gap between the inner tube and the solid sample is larger than the gap between the outer tube and the solid sample.

  By making the gap between the inner tube and the solid sample larger than the gap between the outer tube and the solid sample, the carrier gas that has flowed through the second flow path is likely to flow to the first flow path side, and conversely, it is difficult to leak to the outside air side. can do. Furthermore, while ensuring fluid communication with the outside, it is possible to make it difficult for outside air to enter the ablation chamber including the second channel from the outside, and to suppress contamination of the sample aerosol.

  Furthermore, a preferred embodiment of the laser ablation mass spectrometer according to the present invention is provided only in the first flow path while mass analysis of the sample aerosol derived from the solid sample is performed in the ICP-MS apparatus. Control is performed to continuously introduce the carrier gas in the direction toward the solid sample.

  In the laser ablation mass spectrometer of the present invention, since the lower part of the ablation chamber is open to the outside air with the solid sample, laser ablation of the arbitrary area on the surface of the solid sample and its mass analysis are completed, and a separate area is provided. In performing laser ablation, the sample aerosol remaining in the ablation chamber can be effectively exhausted to the outside. This is an effect that cannot be achieved by the conventional laser ablation mass spectrometer that forms the sealed space described above.

  Therefore, while performing the mass analysis of the arbitrary area in the ICP-MS apparatus, the control of the mass analysis is performed by performing the control to continuously introduce the carrier gas toward the solid sample only in the first flow path. In the meantime, the inside of the ablation chamber is cleaned, and when mass spectrometry is completed, it is possible to smoothly shift to laser ablation in a separate area. Therefore, the problem that the sample aerosol in another area remains in the ablation chamber and the effect is reflected in the mapping analysis results, as in the conventional laser ablation mass spectrometer, is effectively eliminated, and the efficiency Laser ablation mass spectrometry can be realized.

  As can be understood from the above description, according to the laser ablation mass spectrometer of the present invention, the sample aerosol formed by ablating the solid sample can be smoothly provided from the ablation chamber to the ICP-MS apparatus, and from the outside air. Therefore, high-precision laser ablation mass spectrometry and mapping analysis can be executed efficiently.

It is a schematic diagram showing a laser ablation mass spectrometer of the present invention, and is a diagram showing an embodiment of an ablation chamber constituting the laser ablation device in a longitudinal sectional view and showing a carrier gas flow. It is a perspective view of one embodiment of an ablation chamber. It is the longitudinal cross-sectional view of other embodiment of an ablation chamber, and is the figure shown with the flow of carrier gas. (A), (b) is the longitudinal cross-sectional view of other embodiment of an ablation chamber, and is the figure shown with the flow of carrier gas. Regarding CAE analysis for obtaining the relationship between the length of the gap and the gas flow rate in the introduction path, and the relationship between the introduction path length and the gas flow rate in the introduction path, (a) is an explanatory view of the ablation chamber model, and (b) is the length of the gap. (C) is a CAE analysis result showing the relationship between the introduction path length and the gas flow rate in the introduction path. Regarding CAE analysis for obtaining the relationship between the length of the flange and the amount of gas introduced into the introduction path, (a) is an explanatory diagram of the ablation chamber model, and (b) is the CAE analysis for obtaining the relationship between the length of the flange and the amount of introduced gas. It is a result.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing a laser ablation mass spectrometer of the present invention, and more particularly, a longitudinal sectional view showing an embodiment of an ablation chamber constituting the laser ablation apparatus, and FIG. 2 is an ablation chamber. It is a perspective view of one embodiment.

  In the illustrated laser ablation mass spectrometer 100, the ablation chamber 3 of the laser ablation apparatus 10 (hereinafter referred to as LA apparatus 10) and the mass analysis chamber of the inductively coupled plasma mass spectrometer 20 (hereinafter referred to as ICP-MS apparatus 20) are the LA apparatus 10. In general, the fluid is communicated via an introduction path 4 that constitutes the above.

  The LA apparatus 10 includes an optical system including a laser transmitter 1 that emits a high-intensity laser such as an Nd-YAG laser, a refraction lens 11 that refracts the laser, and a condenser lens 12 that condenses the refracted laser. , A carrier gas supply system composed of a gas tank containing an inert gas such as argon or helium and a pump providing the same, a laser L that circulates the carrier gas and irradiates the solid sample passes, The ablation chamber 3 in which the sample aerosol AE generated by ablating the S surface temporarily stays, and the introduction path 4 for fluid communication between the ablation chamber 3 and the mass analysis chamber of the ICP-MS apparatus 20 are configured. In the example shown in the figure, a CCD camera is mounted above the refractive lens 11, and image data here is transmitted to a TV monitor (not shown), and confirmation of laser focusing at the ablation point is performed on the TV. It can be done on the monitor.

  The ablation chamber 3 is fixed in a posture in which a gap G is provided between the ablation chamber 3 and the solid sample S placed on the stage ST by locking means or suspension fixing means (not shown). When ablation and mass analysis of an arbitrary point or area of a solid sample are executed, the stage ST is moved (X1 direction), and ablation and mass analysis of another point or area are executed. The stage ST is an XY table that can move on a plane (X axis and Y axis), and is controlled to laser ablate each point or each area on the surface of the solid sample spreading in a desired order. Is done.

  Since the laser ablation mass spectrometer 100 has a characteristic configuration, particularly in the ablation chamber 3 of the LA apparatus 10, a conventionally known ICP-MS apparatus 20 can be applied, and its specific internal configuration is illustrated. Is omitted. For example, when a sample aerosol derived from a solid sample is carried and introduced by a carrier gas into a mass spectrometry chamber communicating with the introduction path 4, high-frequency power is supplied to a coil wound around a plasma torch, thereby causing a plasma An inductively coupled plasma is generated in the torch, and after the sample aerosol is ionized by this plasma, mass analysis is performed by a mass spectrometer. Note that mass analysis is executed for each area of the solid sample surface, and a mass analysis map of the surface of the solid sample is created by performing mapping analysis.

  In addition to the above-described stage ST movement control, laser transmitter 1 operation ON / OFF control, carrier gas supply ON / OFF control of the carrier gas supply device 2 and their relative control timing, high frequency power supply control, mass The execution control of the analyzer is executed by a computer (not shown), and setting values relating to the laser intensity, the flow rate (or flow velocity) of the carrier gas, etc. are stored in the computer, and based on this. A series of laser ablation mass spectrometry is performed.

  The ablation chamber 3 is composed of a double-pipe structure composed of an outer tube 32 and an inner tube 31, and the inner tube 31 defines a first flow path 31 a, and the inner tube 31 and the outer tube 32. A space between the first channel 31a and the ICP-MS device 20 is provided at the midway position of the inner pipe 31.

  The laser L flowing in the first flow path 31a ablates the surface of the solid sample S, and the sample aerosol AE is generated in the first flow path, and is synchronized with or subsequent to the laser irradiation. 2 is introduced in a direction toward the solid sample S side in the first flow path 31a and the second flow path 32a (Y1 direction).

  The carrier gas introduced into the second flow path 32a is reflected on the surface of the solid sample S through the gap G below (a Y3 direction), and part of the carrier gas enters and stays in the first flow path 31a. The sample aerosol AE is carried to the introduction path 4 (Y4 direction). The introduction of the sample aerosol AE into the introduction path 4 is performed by a carrier gas flow (Y4 direction) from below and a carrier gas flow (Y5 direction) from above. Further, among the carrier gas introduced into the second flow path 32a, gas other than the carrier gas that enters the first flow path 31a leaks to the outside through the outer gap G (Y2 direction).

  Thus, even if there is a gap G between the ablation chamber 3 and the solid sample S, the ablation chamber 3 has a double tube structure, and the flow of the carrier gas flowing through the second flow path 32a outside thereof is By being present, it is reflected and enters the first flow path 31a, so that the sample aerosol AE can be lifted upward and introduced into the introduction path 4.

  In addition, since the carrier gas flowing through the second flow path 32a forms an air barrier that blocks the outside and the inside of the ablation chamber 3, leakage of the generated sample aerosol AE is effectively suppressed.

  On the other hand, while mass spectrometry of the sample aerosol AE derived from the solid sample is being performed in the ICP-MS apparatus 20, the control continues to introduce the carrier gas only in the direction toward the solid sample S into the first channel 31a. The carrier gas after cleaning the inside of the first flow path 31a is exhausted to the outside through the gap G.

  By performing such cleaning control, the first channel 31a can be cleaned in parallel with the mass analysis, and the stage ST can quickly move and ablation of another area can be executed after the mass analysis is completed. Therefore, efficient laser ablation mass spectrometry can be performed. Further, by continuously introducing the carrier gas into the first flow path 31a and exhausting it to the outside, the cleaning effect in the first flow path 31a is enhanced, and in the subsequent mass analysis in the test area The problem that the influence of the sample aerosol in the test area that precedes the process cannot enter and precise mapping analysis cannot be performed cannot occur.

  As described above, the ablation chamber 3 having a double-pipe structure shown in the figure is applied to the ICP-MS apparatus 20 by performing ablation while fixing the desired gap G between the solid sample S and a posture. While ensuring the provision of the sample aerosol AE, the cleaning performance in the ablation chamber 3 is excellent, and precise mass analysis results and mapping analysis results can be obtained.

  3, 4 a, and b each show another embodiment of the ablation chamber.

  The ablation chamber 3A shown in FIG. 3 has a triple tube structure, and has an outermost tube 33 on the outer side of the outer tube 32, and a third flow formed between the outer tube 32 and the outermost tube 33. A carrier gas flows through the path 33a.

  The carrier gas (Y3 direction) that flows through the second flow path 32a and the third flow path 33a and is reflected by the solid sample S lifts the sample aerosol AE that enters and stays in the first flow path upward.

  Since it has a triple-pipe structure, both the outside air flows into the ablation chamber 3A through the gap G and the sample aerosol AE leaks from the ablation chamber 3A through the gap G to the double-pipe structure. In comparison, it is further suppressed. This is because the pressure loss increases in the process until the outside air enters the first flow path 31a, and a double air barrier is formed by the carrier gas flowing through the second and third flow paths 32a and 33a. Therefore, the sample aerosol can be introduced into the ICP-MS apparatus 20 via the introduction path 4 with as little carrier gas as possible or with as low a carrier gas as possible.

  On the other hand, the ablation chamber 3B shown in FIG. 4a has a double tube structure, but includes a flange 5 projecting outward at the lower end of the outer tube 32.

  Since the outer tube 32 having a double tube structure is provided with the flange 5 projecting outward on the end surface facing the solid sample S, outside air enters through the gap G below the flange 5 or through the gap G. Since the distance until the sample aerosol AE leaks to the outside becomes long and the pressure loss becomes large, it becomes difficult for the outside air to enter and the carrier gas and the sample aerosol hardly leak to the outside. In addition, although illustration is abbreviate | omitted, embodiment which provided the flange in the lower end of the outermost pipe | tube 33 in the ablation chamber 3A of the triple pipe structure shown in FIG.

  Further, the ablation chamber 3C shown in FIG. 4b has a gap t1 between the inner tube 31 and the solid sample S larger than a gap t2 between the outer tube 32 and the solid sample S. By adjusting the gap, The carrier gas flowing through 32a and reflected by the solid sample S easily enters the first flow path 31a, and is difficult to leak to the outside through the gap G having the length t2. Furthermore, the entry of outside air through the gap G having the length t2 can be suppressed. Although not shown, also in this embodiment, in the triple tube structure ablation chamber 3A shown in FIG. 3, the gap between the outermost tube 33 and the solid sample S is made the shortest, and the outer tube 32 and the inner tube 31. An embodiment in which each gap is made longer than that may be used.

[Verification of the gap length and the inner diameter of the introduction path to ensure the proper flow velocity of the carrier gas carrying the sample aerosol in the introduction path and its results]
The inventors of the present invention conducted verification to identify a factor that guarantees an appropriate flow rate of the carrier gas in the introduction path. The ablation chamber constituting the laser ablation mass spectrometer of the present invention is simulated in FIG. 5a. In the drawing, the length of the gap G is t, the length of the introduction path 4 (length from the outer tube 32) is s, and the inner diameter of the introduction path 4 is d.

  According to the present inventors, the appropriate flow rate of the carrier gas introduced into the mass analysis chamber of the ICP-MS apparatus 20 through the introduction path 4 is specified to be about 1 to 2 m / sec. When the flow velocity exceeds 2 m / sec, the sample aerosol passing through the mass analysis chamber in the analysis target is too fast for mass analysis. When the flow velocity is less than 1 m / sec, a sufficient amount of sample aerosol for mass analysis is mass analyzed. The reason why the numerical value is limited is that it is difficult to be provided in the chamber.

  Accordingly, the present inventors specify the length of the introduction path 4: s in specifying the ablation chamber components that guarantee carrier gas flow velocity in the introduction path: 1-2 m / sec and their numerical values or numerical ranges. Various changes were made to verify the flow velocity in the introduction passage by CAE analysis, and then the flow velocity (maximum flow velocity) in the introduction passage 4 was examined by CAE analysis by variously changing the length G of the gap G. FIG. 5b shows a CAE analysis result related to the length of the introduction path, and FIG. 5c shows a CAE analysis result related to the length of the gap. In the analysis regarding the length of the introduction path, the carrier gas flow rate provided in the ablation chamber is 110 ml / sec, the inner diameter of the introduction path is 4 mm, and the length of the gap is 4 mm. In the analysis regarding the length of the gap G, the carrier gas flow rate provided in the ablation chamber is 110 ml / sec, the inner diameter of the introduction path is 4 mm, and the length of the introduction path is 1000 mm.

  From the analysis results of FIGS. 5b and 5c, the pressure loss increases as the length of the introduction path increases, and the amount of carrier gas leaking to the outside increases as the gap length increases. -The flow rate of the carrier gas introduced into the MS device decreases.

  In FIG. 5b, it is verified that even when the length of the introduction path is about 100 mm, which is the shortest, the flow velocity is about 0.7 m / sec and does not fall within the range of 1 to 2 m / sec described above.

  On the other hand, even when the length of the gap is about 0.05 mm, which is the minimum length assumed in the actual machine, the flow velocity is about 0.3 to 0.4 m / sec. It has been verified that it is far away.

  From the above analysis results, it was specified that even if the length of the introduction path in the ablation chamber and the length of the gap with the solid sample were adjusted, it was not possible to achieve the carrier gas flow rate of 1 to 2 m / sec in the introduction path.

  On the other hand, the following general formulas are well known to those skilled in the art regarding the pressure loss and gas flow rate when the fluid flows in the pipeline.

ここで、ｄＰは圧力損失、μはガス粘性、Ｌは導入路の長さ、Ｑがガスの流量、ｄは導入路の内径。

Here, dP is the pressure loss, μ is the gas viscosity, L is the length of the introduction path, Q is the flow rate of the gas, and d is the inner diameter of the introduction path.

  From Equation 1, when the gap length is 4 mm and the introduction path length is 1000 mm, the introduction path inner diameter is 10 mm, and when the gap length is 1 mm and the introduction path length is 1000 mm, the introduction path inner diameter is It was found that the flow velocity in the introduction path: 2 m / sec can be achieved by setting it to 8 mm (any combination is highly likely to be applied in actual equipment). That is, using the above general, it has been found that the combination of the length of the gap where the flow velocity in the introduction path is 1 to 2 m / sec and the inner diameter of the introduction path should be studied.

[Verification of the relationship between the length of the flange and the amount of gas introduced into the introduction path, and the results]
The present inventors conducted verification to identify the relationship between the length of the flange and the amount of gas introduced into the introduction path. The ablation chamber constituting the laser ablation mass spectrometer of the present invention is simulated in FIG. 6a. In the figure, the length of the gap G is t, and the length of the flange 5 is r. The CAE analysis result is shown in FIG. In the graph showing the analysis result in FIG. 6b, the amount of introduced gas when the flange length is variously changed based on the flange length of 2 mm and the introduced gas amount at that time: 0.08 cc / sec is specified. In addition, the magnification with respect to the reference value is shown in FIG. In this analysis, the gap is 4 mm.

  From FIG. 6b, as the flange becomes longer, the pressure loss of the carrier gas that tries to leak to the outside through the gap increases, and the amount of leakage of the carrier gas is reduced. Therefore, the carrier provided into the ablation chamber It was found that even if the amount of gas is the same, the amount of carrier gas provided to the introduction path can be increased.

  For example, from FIG. 6b, it is specified by this CAE analysis that the carrier gas introduction amount to the introduction path can be increased by about 1.5 times by setting the length of the flange to about 2 mm to 20 mm.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 ... Laser transmitter, 2 ... Carrier gas supply system, 3, 3A, 3B, 3C ... Ablation chamber, 31 ... Inner tube, 32 ... Outer tube, 33 ... Outermost tube, 31a ... First flow path, 32a ... 2nd flow path, 33a ... 3rd flow path, 4 ... introduction path, 5 ... flange, 10 ... laser ablation apparatus (LA apparatus), 20 ... inductively coupled plasma mass spectrometer (ICP-MS apparatus), 100 ... Laser ablation mass spectrometer (LA-ICP-MS apparatus), S ... solid sample, ST ... stage, AE ... sample aerosol, G ... gap

Claims (5)

A laser ablation device (LA device) consisting of a laser transmitter and an ablation chamber in which a solid sample is accommodated, and fluid communication with the ablation chamber, the vaporized sample aerosol is introduced together with the carrier gas, and mass analysis of the sample aerosol In a laser ablation mass spectrometer consisting of an inductively coupled plasma mass spectrometer (ICP-MS apparatus)
The ablation chamber is composed of a double pipe structure composed of an outer tube and an inner tube. The inner tube is a first channel, and the space between the inner tube and the outer tube is a second channel. Yes,
An introduction path is provided in fluid communication between the first flow path and the ICP-MS device at an intermediate position of the inner pipe;
The ablation chamber is fixed in a posture with a gap between the solid sample and a sample aerosol is generated by laser ablation, and a carrier gas is directed to the solid sample in the first channel and the second channel. A laser ablation mass spectrometer that is introduced so that the carrier gas flowing in the second flow path is reflected by the surface of the solid sample and guided to the first flow path to guide the sample aerosol to the introduction path. The ablation chamber is composed of a triple-pipe structure with a separate outer tube on the outer side of the outer tube, and a space between the outer tube and the separate outer tube is a third flow path,
The ablation chamber is fixed in a posture with a gap between the solid sample and the sample aerosol is generated by laser ablation, and a carrier gas is supplied to the first flow path, the second flow path, and the third flow path. Introduced in the direction toward the solid sample, the carrier gas flowing through the second flow path and the third flow path is reflected from the surface of the solid sample and guided to the first flow path so that the sample aerosol is guided to the introduction path. The laser ablation mass spectrometer according to claim 1.   3. The laser ablation mass spectrometer according to claim 1, wherein the outer tube or the separate outer tube includes a flange projecting outward from an end surface facing the solid sample. 4.   The laser ablation mass spectrometer according to any one of claims 1 to 3, wherein the gap between the inner tube and the solid sample is larger than the gap between the outer tube and the solid sample.   While mass analysis of the sample aerosol derived from the solid sample is being performed in the ICP-MS apparatus, control is continued to introduce the carrier gas toward the solid sample only in the first flow path. The laser ablation mass spectrometer according to any one of claims 1 to 4.

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