WO2011080959A1 - Mass spectroscope, control device of mass spectroscope, and mass spectrometry method - Google Patents

Abstract

Disclosed are a mass spectroscope, a control device of the mass spectroscope, and a mass spectrometry method, wherein even if a flying ion decays, the abundance of the ion can be accurately measured. Specifically disclosed is a mass spectroscope (1007) for measuring the abundance of a specific component in an atmosphere gas, said mass spectroscope being provided with an ion generation source (31a, 31b), a quadrupole mass spectrometer (34a, 34b), a collector (33a) which detects a first ion current of an ion (35a) at a first flight distance (L1) from the ion generation source (31a), and a collector (33b) which detects a second ion current of an ion (35b) at a second flight distance(L2) longer than the first flight distance (L1). A control unit of the mass spectroscope (1007) provided with the above mentioned configuration calculates the abundance of a specific ion from the detected first and second ion currents.

Description

Mass spectrometer, controller for mass spectrometer, and mass spectrometry method

The present invention relates to a mass spectrometer that measures the abundance of a specific component in an atmosphere gas to be measured, a controller of the mass spectrometer, and a mass spectrometry method.

In vacuum processes such as sputtering, it is important to know the abundance of specific components in the process atmosphere gas. In a mass spectrometer for that purpose, the atmosphere gas is ionized by an ion source, the ions are fractionated by a mass spectrometer, and the fractionated ions are measured as a current by a collector. This ion current corresponds to the abundance of the component of the atmosphere to be measured.

The mass analyzer has a special electromagnetic field area, and only specific ions pass through the area to perform mass separation. A typical mass analyzer is a quadrupole mass analyzer, in which a high frequency electric field and a direct electric field are applied to four electrodes (rods). The length of the rod in the quadrupole mass analyzer is related to the performance as a mass analyzer, but can be an arbitrary length within a certain range. FIG. 1A is a cross-sectional view of a conventional quadrupole mass spectrometer.

In FIG. 1A, the quadrupole mass spectrometer has four electrodes (rods) 4, and four electrodes through the openings formed in extraction electrode 2 of ions 5 emitted from ion source 1. It passes between 4 and is incident on the detector 3. At this time, of the four electrodes 4, the opposing electrodes (facing each other with the central axis of the mass analyzer facing each other) are electrically coupled (conducted), and direct current voltage (DC) and high frequency voltage ( The above special electromagnetic field (also referred to as a quadrupole electric field) is formed by applying a voltage obtained by superposing RF), and only ions having a mass number corresponding to each voltage, frequency, etc. It is made to pass through.

The mean free path is an average value of a path in which ions and the like can freely fly in the atmosphere, and is about 7 mm in an atmosphere of pressure (1 Pa) applied in the sputtering process. Therefore, if the rod length of the quadrupole mass spectrometer is 7 mm, the ion current that can reach the collector due to the collision with the atmosphere gas is attenuated to about 1 / e (0.37).

In fact, since the rod length needs to be about 10 to 30 mm from the viewpoint of performance, attenuation of ion current is inevitable in the sputtering process. The attenuation condition of the ion current is determined by the relationship between the flight distance (rod length) of the ion and the mean free path in the atmosphere. FIG. 1B shows an example of the situation in which the number of ions is attenuated by flight. In FIG. 1B, reference numeral 6 is the original (before attenuation) ion current, and reference numeral 7 is the measured (after attenuation) ion current.

Japanese Patent Application Laid-Open No. 11-31473 JP 2008-209181 A JP 2004-349102 A JP 2008-186765 A

As described above, when the ion current corresponding to the amount of component decays, it becomes impossible to know the correct amount of component. Therefore, conventionally, the pressure of the atmosphere is separately measured by means, and the measured ion current is corrected by a conversion formula determined by the pressure value to obtain the original (non-damped) ion current. However, since the above conversion equation changes depending on the conditions of the apparatus and the measurement, the accuracy of correction is poor, and a means for measuring the pressure is also required, which makes the apparatus complicated.

The present invention has been made in view of such problems, and its object is to provide a mass spectrometer and a mass spectrometer capable of accurately measuring the abundance of the flying ions even if the ions are attenuated. And providing a control device and a mass spectrometry method.

In order to achieve such an object, the present invention relates to a mass spectrometer, which comprises: an ion source; and an end of a first moving path for passing ions generated by the ion source. Detecting means for detecting a current value of 1 and detecting a second current value of the specific ion at an end of a second moving path which passes the ions longer than the first moving path; Calculation means for calculating the abundance of the specific ion generated in the ion generation source from the first and second current values, and a first one for passing only the specific ion in at least a part of the first movement path And a second mass separation unit that allows only the specific ions to pass through at least a part of the second movement path.

Furthermore, the present invention is a mass spectrometry method for measuring the abundance of a specific ion, wherein the step of generating the specific ion from an ion generation source, and a mass moved by a first moving distance from the ion generation source A first current value of the particular ion separated is detected, and a second movement distance longer than a first movement distance from the ion generation source is moved for mass separation of a second of the specific ion separated. The method may include the steps of detecting a current and calculating the abundance of the specific ion from the detected first and second currents.

According to the present invention, the current of ions flying only for the first flight distance and the current of ions flying for a second flight distance longer than the first flight distance is an original without collisional attenuation. Since the ion current is determined, even if the flying ions are attenuated, the abundance of the ions can be accurately measured.

It is sectional drawing of the conventional quadrupole mass spectrometer. It is a figure which shows an example of the condition where the number of ions attenuates by flight. It is a figure for demonstrating the principle of this invention. It is a figure for demonstrating the principle of this invention. It is a figure showing the mass spectrometer which measures the mean free path concerning a 1st embodiment of the present invention. It is a figure which shows the apparatus which measures the mass spectrometry mean free path concerning the 2nd Embodiment of this invention. FIG. 7 shows an apparatus for measuring mass spectrometry mean free path according to a third embodiment of the present invention. FIG. 7 shows an apparatus for measuring mass spectrometry mean free path according to a fourth embodiment of the present invention. It is sectional drawing of the quadrupole mass spectrometer shown to FIG. 6A. FIG. 14 is a diagram showing an apparatus for measuring mass spectrometry mean free path according to a fifth embodiment of the present invention. FIG. 14 is a diagram showing an apparatus for measuring mass spectrometry mean free path according to a sixth embodiment of the present invention. It is sectional drawing of the TOF type | mold mass spectrometer shown to FIG. 8A. It is a block diagram which shows schematic structure of the control system in the apparatus which measures a mean free stroke based on this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings described below, components having the same function are denoted by the same reference numerals, and the repetitive description thereof is omitted.
The situation of the decay of ions due to collisions with the atmosphere gas is determined by the mean free path and the ion flight distance, so if mass spectrometers with different flight distances of ions are installed in the same vacuum region, two ions The change in current is a different exponential function. However, if the conditions other than the flight distance attenuation condition are the same, then the mantissas of the exponential functions become the same, resulting in two exponential functions differing only in the exponent. These situations are shown in FIGS. 2A and 2B.

FIG. 2A is a diagram for explaining the principle of a mass spectrometer according to one embodiment of the present invention. In one embodiment of the present invention, mass analysis with the flight distance of two different ions is performed in the same vacuum region. Therefore, a first mass analyzer (mass separation area) performing mass separation in at least a part of a first flight distance of ions in the same vacuum region, and an ion longer than the first flight distance And a second mass analyzer (mass separation area) for performing mass separation at least a part of the second flight distance of

In FIG. 2A, in the first configuration corresponding to the first flight distance where the flight distance is relatively short, the collector (detector) 23a is separated from the ion source 21a (ion generation source) by the first flight distance L1. A (first detector) is disposed, and a mass spectrometer (mass sorting area) 24a is disposed between the extraction electrode 22a and the collector 23a. That is, since the mass analyzer 24a is disposed between the ion source 21a and the collector 23a spaced apart from the ion source 21a by the first flight distance L1, the mass analyzer 24a Mass separation is performed at least a part of the flight distance L1 of 1. As described above, since the ions 25a generated in the ion source 21a are detected by the collector 23a, the region between the ion source 21a and the collector 23a functions as a first moving path for passing the ions 25a. The ions 25a are detected at the end of the first movement path (collector 23a in FIG. 2A).

The mass analyzer 24a as a first mass separation means configured to pass only specific ions in at least a part of the first movement path is, for example, a quadruple having four electrodes (rods). It can be a polar mass spectrometer. As described above, in the case of using a quadrupole mass spectrometer, electrically connect (conduct) one of the four electrodes 4 facing each other (facing each other with the central axis of the mass analyzer). A quadrupole electric field is formed by applying a voltage in which a direct current voltage (DC) and a high frequency voltage (RF) are superimposed between electrode sets, and only ions having a mass number corresponding to each voltage, frequency, etc. It is made to pass in the longitudinal direction of the electrode. Accordingly, the ions 25a emitted from the ion source 21a fly through the mass analyzer 24a through the opening of the extraction electrode 22a and are input to the collector 23a. In this manner, the collector 23a causes the first ion current IL1 (ion current value IL1 (hereinafter, the ion current value may be simply referred to as "ion current")) of the ions 25a at the first flight distance. To detect.

Similarly, in the second configuration corresponding to the second flight distance having a relatively long flight distance, which is disposed in the same vacuum region as the first configuration, the second source from the ion source 21b (ion generation source) Collector (detector) 23b (second detector) is disposed spaced apart by a flight distance L2 of, and a mass analyzer (mass separation region) 24b is disposed between extraction electrode 22b and collector 23b. There is. That is, since the mass analyzer 24b is disposed between the ion source 21b and the collector 23b spaced apart from the ion source 21b by the second flight distance L2, the mass analyzer 24b Mass separation is performed at least a part of the flight distance L2 of two. As described above, since the ions 25b generated in the ion source 21b are detected by the collector 23b, the region between the ion source 21b and the collector 23b functions as a second moving path for passing the ions 25b. The ion 25b is detected at the end of the second movement path (the collector 23b in FIG. 2A).

The mass analyzer 24b as a second mass separation means configured to pass only specific ions in at least a part of the second movement path has, for example, a quadruple having four electrodes (rods). It can be a polar mass spectrometer. The ions 25b emitted from the ion source 21b fly through the mass analyzer 24b through the opening of the extraction electrode 22b and are input to the collector 23b. In this manner, the collector 23b detects the second ion current IL2 of the ions 25b at a second flight distance longer than the first flight distance.

In the configuration of FIG. 2A, the ion current IL1 as the first current value and the ion current IL2 as the second current value are directly obtained from the measurement results of the collectors 23a and 23b, respectively. In the above, it is sufficient if the current values at the ends of the first and second movement paths can be determined as a result. Thus, in one embodiment of the present invention, the first and second current values may be determined indirectly.

Further, in FIG. 2B, reference numeral 26 is a graph showing the relationship between the ion current and pressure originally (before attenuation), ie, assuming no collision with the atmosphere gas, and reference numeral 27 represents the ion current after attenuation. Is a graph showing the relationship between the ion current (ion current detected by the collector 23a) and the pressure when the flight distance is short, and the reference numeral 28 is the ion current after attenuation, and the flight distance is It is a graph which shows the relationship between the ion current (ion current detected by the collector 23b) in the case of a long and a pressure.

As described above, when the first and second flight distances and the ion current for each of the flight distances are known, it is possible to calculate the ion current (original ion current) when not attenuated. The flight distance is somewhat arbitrary, but its value must be known exactly. In addition, since the pressure of the atmosphere is not used for this calculation, it is not necessary to separately measure it. That is, unlike the prior art, it is not necessary to measure the pressure of the atmosphere, and in order to obtain the original ion current, it is also necessary to correct the ion current using a pressure conversion formula which changes depending on the device and measurement conditions. There is not. Therefore, the original ion current can be accurately measured regardless of the apparatus and measurement conditions.

Now, assuming that the original ion current is I0, the mean free path is λ, the two flight distances are L1 and L2, and the ion current is IL1 and IL2, respectively, the attenuation equation
IL1 = I0 · exp (−L1 / λ) (1)
IL2 = I0 · exp (−L2 / λ) (2)
Formulas (1) and (2) are obtained by taking logarithms and arranging
λ = −L1 / Loge (IL1 / I0) (3)
λ = −L2 / Loge (IL2 / I0) (4)
When λ is eliminated from the equations (3) and (4),
L1 / Loge (IL1 / I0) = L2 / Loge (IL2 / I0) (5)
Since all values other than the original ion current I0 of equation (5) are known (L1, L2: set values, IL1, IL2: measured values at collectors 23a, 23b, for example), the original value can be obtained from equation (5) The ion current I0 is calculated. Thus, equation (5) becomes independent of the mean free path λ, and can be calculated from the set values L1 and L2 that are accurately determined, and the measured values IL1 and IL2 at the collector. Even if it does not perform the correction by the conversion value decided by the pressure which needs measurement, highly accurate measurement can be performed.

However, in the above equation, it is assumed that "the conditions other than the attenuation condition by the flight distance are the same", but the conditions are not completely the same in practice. Therefore, it is desirable to measure the ratio of the ion current at low pressure with no attenuation or low, and to correct the actual measurement value. This is called "non-attenuation correction".

The above-mentioned "non-attenuation calibration" will be described.
In the above non-attenuation correction, first, the ion currents IL1-A and IL2-A at the respective collectors 23a and 23b are measured at a good pressure (low pressure) at which the decay can be ignored, and the values are set to initial values ( Set as a value without attenuation). Then, in actual measurement, the ion current IL1 and IL2 actually measured in each of the collectors 23a and 23b may be normalized to a value divided by this initial value. If the current values detected at the collectors 23a and 23b are a to b without attenuation and d to e with attenuation, IL1 to IL2 becomes (d / a) to (e / b).

In this specification, this process for producing an initial value will be referred to as "attenuation without calibration". That is, calibration without attenuation is detected at the first collector and the second collector in the state of the first degree of vacuum (pressure, for example, in the state of good degree of vacuum (state of low pressure)). According to the ratio of the number of charged particles, the first collector and the second in a state of a second degree of vacuum (pressure, for example, a state of degree of vacuum worse than the first degree of vacuum (high pressure state)) It is to calibrate the ratio of the ion current detected in the collector.

The mass spectrometer 1007 described in each embodiment described later can incorporate the control unit 1000 shown in FIG. Further, the control unit may be connected via an interface.

FIG. 9 is a block diagram showing a schematic configuration of a control system according to an embodiment of the present invention.
In FIG. 9, reference numeral 1000 denotes a control unit as a control unit that controls the entire mass spectrometer 1007. The control unit 1000 includes a CPU 1001 that executes processing operations such as various calculations, controls, and determinations, and a ROM 1002 that stores various control programs and the like executed by the CPU 1001. The control unit 1000 further includes a RAM 1003 for temporarily storing data and input data during processing of the CPU 1001, and a non-volatile memory 1004 such as a flash memory and an SRAM.

In addition, the control unit 1000 displays various displays including an input operation unit 1005 including a keyboard or various switches for inputting predetermined commands or data, and an input / setting state of the mass spectrometer 1007. A unit 1006 (for example, a display) is connected.

In the present specification, the "flying distance" is a distance determined by the configuration and conditions of the apparatus used, and from the surface emitting ions of a member capable of emitting ions (for example, the ion emitting surface of the ion source) It is the distance that the emitted ions actually fly (travel) on the assumption that they travel without vibration to a predetermined collector. The simplest example of the flight distance is the distance from the ion generation surface of the ion source to the ion trapping surface of the collector in an apparatus having one ion source and one collector. That is, the flight distance of an ion is the movement distance that the ion moved along the movement path (the first movement path or the second movement path) of the ion, that is, the length of the movement path of the ion. Thus, for example, in the configuration of FIG. 2A, the ions 25a (ions 25b) generated from the ion source 21a (ion source 21b) move by the first moving distance (second moving distance), and mass separation is performed halfway , Mass-separated specific ions are incident on the collector 23a (23b).

First Embodiment
FIG. 3 is a view showing a mass spectrometer 1007 according to the first embodiment of the present invention.
In the present embodiment, two quadrupole mass spectrometers 30a and 30b having different lengths of rods (electrodes) are installed in the same vacuum region. The quadrupole mass spectrometers 30a and 30b include ion sources 31a and 31b, extraction electrodes 32a and 32b, quadrupole mass analyzers 34a and 34b having four electrodes (rods), and collectors 33a and 33b, respectively. Have.

An atmosphere gas (neutral molecule) becomes each ion (mainly a monovalent positive ion) in the ion sources 31a and 31b. The ions 35a and 35b generated by the ion sources 31a and 31b are extracted by an electric field by the extraction electrodes 32a and 32b, respectively, and the energy corresponding to the potential difference with the ion sources 31a and 31b is a quadrupole mass analyzer 34a or 34b. To fly. In the quadrupole mass analyzers 34a and 34b, high frequency electric fields and DC electric fields are applied to the four electrodes (rods), so that only specific ions pass through. As a result, only specific ions subjected to mass separation reach the collectors 33a and 33b and are measured as the ion currents IL1 and IL2.

The distance from the ion source 31a to the collector 33a (first flight distance) is L1, and the distance from the ion source 31b to the collector 33b (second flight distance) is L2. In this embodiment, L1 = 10 mm and L2 = 30 mm.

In the configuration as described above, the ions 35a emitted from the ion source 31a fly in the quadrupole mass spectrometer 34a through the opening of the extraction electrode 32a and are input to the collector 33a. In this way, the collector 33a detects the ion current IL1 of the ions 35a that have traveled by the flight distance L1. In this embodiment, a region between the ion emission surface of the ion source 31a and the ion detection surface of the collector 33a and through which the ions 35a generated from the ion source 31a pass is a first movement path. Therefore, the quadrupole mass spectrometer 30a detects the ion current IL1 (the first current value of the ion to be detected) at the end (collector 33a) of the first movement path. Needless to say, the length of the first movement path is the distance L1.

Similarly, the ions 35b emitted from the ion source 31b fly in the quadrupole mass analyzer 34b through the opening of the extraction electrode 32b and are input to the collector 33b. In this way, the collector 33b detects the ion current IL2 of the ions 35b that have traveled by a flight distance L2 longer than the flight distance L1. In this embodiment, a region between the ion emission surface of the ion source 31b and the ion detection surface of the collector 33b and through which the ions 35b generated from the ion source 31b pass is a second movement path. Therefore, the quadrupole mass spectrometer 30b detects the ion current IL2 (the second current value of the ion to be detected) at the end (collector 33b) of the second moving path longer than the first moving path. . It goes without saying that the length of the second movement route is the distance L2.

As an actual measurement, for example, it may be performed as follows.
First, in an atmosphere with a sufficiently low pressure, the relationship between the amount of a specific component (for example, various expressions such as the pressure, density, and concentration of a specific ion can be made) and the ion current is obtained. That is, I is the collector current, C is the abundance, and for a specific ion (the ion of the gas to be measured), a proportional coefficient (sensitivity) K which is K in the following equation is obtained in advance.
C = K × I (6)
Next, when performing "no decay correction", for the no decay correction, the ion current of the specific ion in the collector 33a and the collector 33b is also determined in the atmosphere with a sufficiently low pressure, and this is calculated as IL1-A, Call it IL2-A. After performing the preliminary measurement up to this point, we move on to the actual measurement. In addition, as a specific value of a sufficiently low pressure, it is necessary for the mean free path to be sufficiently larger than the rod length (electrode length of the quadrupole mass spectrometer), and in this embodiment, for example, 1000 mm. The pressure may be about 7 × 10 ^-3 Pa as the pressure.

In the actual measurement, the ion current of a specific ion in the collector 33a and the collector 33b is determined under the same conditions as the preliminary measurement except for the pressure, and these are determined as IL1-B and IL2-B.

In order to obtain the original ion current without attenuation, the calculation is performed as follows.
When “correction without attenuation” is not performed, the measured IL1-B is substituted into IL1 of Equation (5), and the measured IL2-B is substituted into IL2, and L1 = 10 and L2 = 30 are substituted. Then, the original ion current I0 is determined. The abundance of a specific ion is determined from equation (6) with I 0 calculated in this way as I.

In addition, when performing “non-attenuation correction”, the following equations (7) and (8) are used to make sure that the specific ions at the first and second flight distances are the same (conditions other than attenuation by flight distance The ion currents IL 1 -C and IL 2 -C are calculated.
IL1-C = IL1-B * {IL1-A / (IL1-A + IL2-A)} (7)
IL2-C = IL2-B * {IL2-A / (IL1-A + IL2-A)} (8)
Assuming that IL1-C and IL2-C are IL1 and IL2 respectively, and L1 = 10 and L2 = 30, I0 which is the original ion current of the specific ion is obtained from the formula (5). Further, the amount of a specific ion is determined from the equation (6) with I 0 calculated in this manner as I.

The expansion of a specific expression substitutes L1 = 10 and L2 = 30 into Expression (5),
10 / Loge (IL1 / I0) = 30 / Loge (IL2 / I0)
∴ Loge (IL2 / I0) / Loge (IL1 / I0) = 30/10 = 3
From the logarithm theorem
Log _{(IL1 / I0)} (IL2 / I0) = 3
That is, since the logarithm of (IL2 / I0) to the bottom of (IL1 / I0) is 3,
(IL1 / I0) ³ = IL2 / I0
IL1 ³ / I0 ² = IL 2/1
∴ I0 ² = IL1 ³ / IL2
∴ I0 = (IL1 ³ / IL2) ^1/2 (5a)
Thus, for example, when L1 = 10 and L2 = 30, the original ion current I0 can be obtained by the equation (5a).

The method for determining the abundance of another specific ion is the same as above. Moreover, it is also possible to use past data without performing the above-mentioned preliminary measurement every time.

Furthermore, since the main component (Ar) is determined in sputtering or the like, the following equation (9) can be used instead of (6), where the amount of Ar is CAr and the ion current is IAr.
C = CAr × I / IAr (9)
However, I Ar is also calculated using the equation (5) (also equations (7) and (8) when performing no attenuation correction). CAr uses the value of the total pressure by the vacuum gauge.

Hereinafter, an example of the measurement operation by the mass spectrometer according to the present embodiment will be described.
First, preliminary measurement is performed to determine the proportionality constant K of equation (6). In the present embodiment, an example in which a pressure is used as the abundance will be described.
In the present embodiment, it is necessary to determine the amount C1 of the pressure in a sufficiently low state and the ion current I1 in the state. Therefore, prior to the measurement of the ion current I1, the pressure of a specific gas (gas to be measured) is sufficiently low in a vacuum region (for example, a chamber) in which the mass spectrometer 1007 is disposed. Introduce and measure the pressure at that time with an ionization vacuum gauge. That is, the control unit 1000 controls the ionization vacuum gauge so as to obtain the pressure in the vacuum region, acquires the pressure measured by the ionization vacuum gauge, and stores the pressure in the RAM 1003 as the abundance C1.

Next, in the state where the pressure is sufficiently low, ions (ions of the gas to be measured) are generated from the ion source 31a, and the ions are incident on the quadrupole mass analyzer 34a, and the quadrupole mass analyzer 34a The specific ions (ions of the gas to be measured) are mass-fractionated, and the specific ions are incident on the collector 33a. That is, the control unit 1000 is such that the ion 35a is generated from the ion source 31a, and the mass fractionating apparatus performs mass separation of specific ions from the ions 35a by the quadrupole mass spectrometer 34a (high frequency power source and DC power source etc.). Control 1007 Further, the control unit 1000 controls the mass fractionating apparatus 1007 so that the collector 33 a detects ions, acquires the detected ion current I 1 from the mass fractionating apparatus 1007, and stores the ion current I 1 in the RAM 1003.

As described above, when the abundance C1 and the ion current I1 are obtained, the control unit 1000 reads the abundance C1 and the ion current I1 from the RAM 1003 and obtains the proportional constant K for a specific gas according to equation (6). Are stored in the sex memory 1004.

When the preliminary measurement is completed, an actual measurement is performed.
In the actual measurement, first, the ions 35a and 35b are generated by the ion sources 31a and 31b, and the ions 35a and 35b are input to the quadrupole mass spectrometers 34a and 34b. That is, the control unit 1000 controls the mass spectrometer 1007 so that the ions 35a and 35b are generated from the ion sources 31a and 31b.

Next, the ion currents IL1-B and IL2-B of the ions input to the collectors 33a and 33b are measured. That is, the control unit 1000 controls the mass spectrometer 1007 so that the collectors 33a and 33b detect the ion current, acquires the detected ion currents IL1-B and IL2-B from the mass spectrometer 1007, and controls the RAM 1003. Store in

For example, the value (= 10 mm) of the distance L1 and the value (= 30 mm) of the distance L2 are stored in the non-volatile memory 1004 in advance.

The control unit 1000 reads out the values of L1 and L2 which are setting values from the non-volatile memory 1004, and further reads out the ion currents IL1-B and IL2-B which are measurement values from the RAM 1003, and ion currents IL1-B and IL2-B. The original ion current I0 is calculated according to the equation (5), where IL1 and IL2 respectively.

When the original ion current I0 is calculated, the control unit 1000 reads the proportional constant K from the non-volatile memory 1004, and based on the proportional constant K and the calculated ion current I0, the specific Calculate the abundance of ions. As described above, in the present embodiment, the control unit 1000 reduces the ion currents IL1-B and IL2-B which are the first and second current values measured by the collectors 33a and 33b, respectively. The step of substituting for) is performed to calculate the abundance of the specific ion.

In the present embodiment, “non-attenuation correction” may be performed when calculating the abundance of specific ions. When the “non-attenuation correction” is performed, the ion currents IL1-A and IL2-A are measured at the collectors 33a and 33b, with the pressure being sufficiently low (eg, 7 × 10 ⁻³ Pa or the like). That is, except for the pressure, the conditions are the same as in the actual measurement, and the ion current at the collectors 33a and 33b is set as an initial value without attenuation. Then, each of the measured ion currents is divided by this initial value and normalized to a value to be used for calculation. That is, in the measurement for calibration without attenuation, the collector 33a detects the ion current IL1-A, and the collector 33b detects the ion current IL2-A. The detected ion currents IL1-A and IL2-A are stored in the non-volatile memory 1004, respectively. Therefore, when calibration without attenuation is performed, the control unit 1000 appropriately reads the ion current IL1-A, IL2-A as the initial value stored in the non-volatile memory 1004, and measures the measured value according to the read initial value. Perform calibration without attenuation by normalizing to the value divided by.

For example, when performing non-attenuation correction, the control unit 1000 reads out the ion currents IL1-B and IL2-B detected from the RAM 1003, and further, the ion current IL1-A and IL2-A as initial values from the non-volatile memory 1004. And calculate the non-attenuation corrected ion current IL1-C, IL2-C according to the equations (7), (8). Then, using the ion currents IL1-C and IL2-C and the distances L1 and L2, the control unit 1000 calculates the original ion current I0 according to the equation (5), and the calculated ion current I0 and the calculated ion current I0. The abundance is calculated from the proportional constant K using equation (6).

As described above, in the present embodiment, there is no need to correct and obtain the original ion current by a conversion formula determined by the pressure value depending on the apparatus and measurement method, and the flight distance of the ion can be accurately determined. The measured ion current at the flight distance of two different ions can accurately determine the original ion current.

Second Embodiment
FIG. 4 is a view showing a mass spectrometer 1007 according to the second embodiment of the present invention. In this embodiment, although it is a quadrupole mass spectrometer having one ion source 41 and one quadrupole mass analyzer 44, the electrodes (rods) of the quadrupole mass analyzer are in the longitudinal direction. The collector 43a is separately provided in the middle. The collector 43a is provided with an opening, and some ions are captured and detected here, while other ions pass through to a collector 43b disposed downstream of the quadrupole mass analyzer 44. It is detected.

In FIG. 4, the quadrupole mass spectrometer 44 has four electrodes (rods) 44a of a first length and four electrodes (rods) 44b of a second length, and is a quadrupole. In the longitudinal direction of the mold mass analyzer 44, it is divided into two. In this embodiment, it can be said that the two mass separators are provided: a mass analyzer having four electrodes 44a and a mass separator having four electrodes 44b.

During two divisions (between the mass separation area formed by the electrode 44a and the mass separation area formed by the electrode 44b), a collector 43a for detecting the ions 45 flying the first flight distance L1 is provided. It is provided. In addition, a collector 43 b for detecting the ions 45 that have traveled the second flight distance L 2 is provided at a stage subsequent to the quadrupole mass spectrometer 44.

In this embodiment, the distance L1 (first flight distance) from the ion source 41 to the collector 43a is 10 mm, and the distance L2 (second flight distance) from the ion source 41 to the collector 43b is 30 mm.

In the present embodiment, the collector 43a is a collector having at least one opening, and some ions are detected, but the remaining ions are transmitted as they are and proceed to the collector 43b located farther than the collector 43a. Is configured. By thus configuring the collector 43a, the collector 43a and the collector 43b can be installed in series (two collectors can be arranged on the same ion flight axis), and measurement by one ion source 41 is performed. be able to.

The configuration of the collector 43a may be a mesh shape, a slit shape, or a thin film of a conductive member (for example, a silicon thin film) in addition to the structure having at least one opening. Also good. Under the predetermined conditions, when ions enter the conductive thin film, a part of the ions is captured by the conductive thin film, and the other part is transmitted as it is. As described above, in the present embodiment, any member may be used as the collector 43a as long as it can detect part of the incident ions and allow other parts to pass through.

In the configuration as described above, the ions 45 emitted from the ion source 41 fly through the opening of the extraction electrode 42 in the electrode 44 a (first mass separation region) of the quadrupole mass analyzer 44. Is input to the collector 43a. The collector 43a captures a part of the input ions 45, transmits the other part, and inputs it to an electrode 44b (mass separation area) which the mass spectrometer 44 has. As described above, the collector 43a detects the ion current IL1 of the ions 45 that have traveled by the flight distance L1. In this embodiment, a region between the ion emission surface of the ion source 41 and the ion detection surface of the collector 43a and through which the ions 45 generated from the ion source 41 pass is a first movement path. Therefore, the mass spectrometer 1007 according to the present embodiment detects the ion current IL1 (the first current value of the ion to be detected) at the end (collector 43a) of the first movement path.

The ions 45 transmitted through the collector 43a fly in the electrode 44b of the quadrupole mass spectrometer 44 and are input to the collector 43b. In this manner, the collector 43b detects the ion current IL2 of the ions 45 that have traveled by a flight distance L2 longer than the flight distance L1. At this time, a region surrounded by the four electrodes 44a and a region surrounded by the four electrodes 44b become a second mass separation region in which mass separation is performed at the second flight distance L2. In the present embodiment, a region between the ion emission surface of the ion source 41 and the ion detection surface of the collector 43b and through which the ions 45 generated from the ion source 41 pass is a second movement path. Therefore, the mass spectrometer 1007 according to the present embodiment detects the ion current IL2 (the second current value of the ion to be detected) at the end (collector 43b) of the second moving path longer than the first moving path. Do.

As apparent from FIG. 4, in the present embodiment, the collector 43 a and the collector 43 b are linearly arranged, and the ions 45 generated from the single ion source 41 are relatively close to the ion source 41. The first movement path constitutes a part of the second movement path because the detection is performed by both 43a and the relatively distant collector 43b.

The present embodiment has the same structure as that of the first embodiment except for the division of the rod, and the methods of preliminary measurement, actual measurement, calculation and the like are all the same as those of the first embodiment.
In the present embodiment, the ion source is shared, and the flight regions of the ions also overlap, so the size can be smaller than in the first embodiment.

Third Embodiment
FIG. 5 is a view showing a mass spectrometer 1007 according to the third embodiment of the present invention. In this embodiment, although it is a quadrupole mass spectrometer having one ion source 51, the ion source 51 can extract ions to either of two sides by two extraction electrodes (switching electrodes) 52a and 52b. It has become. Then, two quadrupole mass analyzers (mass separation regions) 54a and 54b and two collectors 53a and 53b are provided on both sides of the ion source 51, and mass separation / detection of ions extracted to either is performed. It can be done.

In FIG. 5, an extraction electrode 52a, a quadrupole mass spectrometer 54a, and a collector 53a spaced from the ion source 51 by a distance L1 are provided in this order on the opposite side of the ion source 51. ing. Further, on the other side opposite to the ion source 51, an extraction electrode 52b, a quadrupole mass spectrometer 54b, and a collector 53b spaced from the ion source 51 by a distance L2 are provided in this order. .

In such a configuration, when a predetermined voltage is applied to the extraction electrode 52a, ions 55a are extracted from the ion source 51 toward the extraction electrode 52a, and the inside of the quadrupole mass spectrometer 54a is opened through the opening of the extraction electrode 52a. It flies and it inputs into collector 53a. In this way, the collector 53a detects the ion current IL1 of the ions 55a that have traveled by the flight distance L1. In this embodiment, a region between the ion emission surface on the collector 53a side of the ion source 51 and the ion detection surface of the collector 53a and through which the ions 55a generated from the ion source 51 pass is the first movement path. It becomes. Therefore, the mass spectrometer 1007 according to the present embodiment detects the ion current IL1 (the first current value of the ion to be detected) at the end (collector 53a) of the first movement path.

Similarly, when a predetermined voltage is applied to the extraction electrode 52b, ions 55b are extracted from the ion source 51 toward the extraction electrode 52b, and fly through the quadrupole mass spectrometer 54b through the opening of the extraction electrode 52b. It is input to the collector 53b. In this way, the collector 53b detects the ion current IL2 of the ions 55b that have traveled by a flight distance L2 longer than the flight distance L1. In this embodiment, a region between the ion emission surface on the collector 53b side of the ion source 51 and the ion detection surface of the collector 53b, and through which the ions 55b generated from the ion source 51 pass, is a second movement path It becomes. Therefore, the mass spectrometer 1007 according to the present embodiment detects the ion current IL2 (the second current value of the ion to be detected) at the end (collector 53b) of the second movement path longer than the first movement path. Do.

In the present embodiment, the structure is the same as that of the second embodiment except for the two extraction electrodes (switching electrodes), and all methods such as preliminary measurement, actual measurement, calculation, etc. are the same as the first embodiment. .
Since the present embodiment is independent except for the sharing of the ion source, it is simpler than the second embodiment.

The collector may be shared from the viewpoint of sharing the components of the mass spectrometer. In this case, for example, in FIG. 5, a collector having a first ion detection surface and a second ion detection surface different from the first ion detection surface (in FIG. 5, two opposing ion detection surfaces are Collector) is replaced with the ion source 51 and arranged. Further, separate ion sources are arranged instead of the collectors 53a and 53b respectively. With such a configuration, it is possible to detect both ions of the first flight distance L1 and ions of the second flight distance L2 with a single collector.

Now, in the first to third embodiments, although the quadrupole mass analyzer as the mass spectrometer is linear, the four electrodes of the quadrupole mass analyzer are nonlinear. The quadrupole mass spectrometer may be non-linear. That is, the first mass separation region (in the first to third embodiments, reference numerals 34a, 44a, 54a in the first to third embodiments) for mass separation at the first flight distance, and the mass separation at the second flight distance At least one of the mass separation regions (in the first to third embodiments, reference numerals 34b, 44b, 54b) may be non-linear.

In mass spectrometry, vacuum ultraviolet rays may be incident on the collector from the ion source in addition to ions. This is because vacuum ultraviolet light (light having high energy) is generated by the ion source. In addition, when ions collide with the electrode of the quadrupole mass spectrometer, soft X-rays (light with higher energy) may be generated and be incident on the collector. Light with high energy incident on the collector due to such vacuum ultraviolet rays, soft X-rays, or other factors is generally referred to as "stray light". That is, stray light may be incident or generated along with ions in a mass separation area such as a quadrupole mass spectrometer.

Therefore, as described above, by forming the mass analyzer as a mass separation region in a non-linear manner, the ions incident on the mass analyzer are electric fields formed by the mass analyzer (quadrupole mass analysis) In the case of a detector, it travels in the above-mentioned non-linear fashion due to the quadrupole electric field, but stray light is reflected inside the mass analyzer or a gap formed in the mass analyzer (a quadrupole mass analyzer In this case, the light is transmitted from the region between the electrodes to the outside. Thus, the incidence of stray light on the collector can be reduced, and the S / N ratio can be further improved.

Fourth Embodiment
FIG. 6A is a view showing a mass spectrometer 1007 according to a fourth embodiment of the present invention. In this embodiment, although it is a quadrupole mass spectrometer having one ion source 61, the ion source 61 can extract ions to either of two sides by two extraction electrodes (switching electrodes) 62a and 62b. It has become. Then, quadrupole mass analyzers (mass separation regions) 64a and 64b having two arc-shaped electrodes (rods) are provided on both sides of the ion source 61, and mass separation of ions extracted to either can be performed. It has become so. However, since the end portions of the two arc-shaped electrodes (rods) are at the same position, the collector 63 is one.

Usually, the electrodes (rods) of the quadrupole mass spectrometer are straight, but being straight is not necessarily an absolute condition. Even if the electrode (rod) is non-linear (for example, arc-shaped), if it has the cross-sectional shape shown in FIG. 6B, the basic mass separation function is maintained. The same applies to the first to third embodiments as described above.

In FIG. 6A, the ions 65a emitted from one side of the opposing ion source 61 are detected by the first ion detection surface 63a of the collector 63, and the ions 65b emitted from the other side of the opposing ion source 61 are detected. , And a second ion detection surface 63 b facing the first ion detection surface of the collector 63.

An extraction electrode 62a is provided on one side of the ion source 61, and an arc-shaped quadrupole mass analyzer 64a is provided downstream of the extraction electrode 62a. A collector 63 is provided downstream of the circular arc quadrupole mass spectrometer 64 a so as to detect ions 65 a by the first ion detection surface 63 a of the collector 63. That is, the quadrupole mass analyzer 64a is formed in a non-linear shape (here, an arc shape) so that the ions 65a of the first flight distance L1 are incident on the first ion detection surface 63a of the collector 63 There is.

On the other hand, an extraction electrode 62b is provided on the other side of the ion source 61, and an arc-shaped quadrupole mass analyzer 64b is provided downstream of the extraction electrode 62b. A collector 63 is provided downstream of the arc-shaped quadrupole mass spectrometer 64 b so as to detect ions 65 b by the second ion detection surface 63 b of the collector 63. That is, the quadrupole mass analyzer 64b is formed in a non-linear shape (here, an arc shape) so that the ions 65b of the second flight distance L2 are incident on the second ion detection surface 63b of the collector 63 There is.

Note that configuring the quadrupole mass analyzers 64a and 64b using four concentric annular electrodes arranges the four electrodes of the quadrupole mass analyzer with high parallelism. Because it can be That is, using four concentric circular electrodes, it is possible to provide a reference point (concentric point) when arranging the four electrodes in parallel. In the configuration as shown in 6B, four arc-shaped electrodes can be arranged with high parallelism.

In such a configuration, when a predetermined voltage is applied to the extraction electrode 62a, ions 65a are extracted from the ion source 61 to the extraction electrode 62a side, and the inside of the quadrupole mass spectrometer 64a is opened through the opening of the extraction electrode 62a. It flies by the first flight distance L 1 and is input to the first ion detection surface 63 a of the collector 63. In this manner, the collector 63 detects the ion current IL1 of the ions 65a that have traveled by the flight distance L1. In the present embodiment, the ion source 61 follows the shape of the quadrupole mass spectrometer 64a between the ion emission surface facing the first ion detection surface 63a and the first ion detection surface 63a. An arc-shaped area through which the ions 65a generated from the ion source 61 pass is a first movement path. Therefore, the mass spectrometer 1007 according to the present embodiment is configured to detect the ion current IL1 (the first current value of the ion to be detected) at the end of the first movement path (the first ion detection surface 63a of the collector 63). To detect.

Similarly, when a predetermined voltage is applied to the extraction electrode 62b, the ions 65b are extracted from the ion source 61 toward the extraction electrode 62b, and the second mass flow in the quadrupole mass spectrometer 64b is made through the opening of the extraction electrode 62b. It flies by the flight distance L 2 and is input to the second ion detection surface 63 b of the collector 63. In this manner, the collector 63 detects the ion current IL2 of the ions 65b flying by the flight distance L2 longer than the flight distance L1. In the present embodiment, the ion source 61 follows the shape of the quadrupole mass spectrometer 64b between the ion emission surface facing the second ion detection surface 63b and the second ion detection surface 63b. A second moving path is an arc-shaped area through which the ions 65 b generated from the ion source 61 pass. Therefore, in the mass spectrometer 1007 according to the present embodiment, the ion current IL2 (the ion to be detected) is detected at the end of the second movement path (the second ion detection surface 63b of the collector 63) longer than the first movement path. The second current value is detected.

In this embodiment, the structure is the same as that of the third embodiment except for the use of an arc electrode (rod) and one collector, and all methods such as preliminary measurement / actual measurement / calculation are the first embodiment and the first embodiment. It is the same.

In the present embodiment, the number of collectors (and the detection system associated therewith) is one, which is simpler than in the third embodiment. Furthermore, since the quadrupole mass analyzers 64a and 64b are formed in a non-linear shape such as an arc shape, it is possible to reduce the incidence of stray light on the collector 63.

In the present embodiment, it is not essential to make the electrode of the quadrupole mass analyzer arc-shaped, but in order to make the apparatus simpler, ions of the first flight distance can be obtained by one collector. And detecting ions of a second flight distance emitted from the same ion source as ions of the first flight distance. At this time, the non-linear trajectory of at least one of the two ion trajectories emitted from a single ion source allows the two ions to be incident on a single collector. . That is, by making at least one of the two mass separation regions (mass analyzers) non-linear and bending the trajectory of at least one of the ions, incidence of ions of two flight distances on a single collector can be realized. ing.

The single collector may be configured to have at least two surfaces of a first ion detection surface and a second ion detection surface different from the first ion detection surface. In FIG. 6A, the first ion detection surface 63a and the second ion detection surface 63b are provided to face each other, and the ions 65a that fly by the first flight distance L1 enter the first ion detection surface 63a. The quadrupole mass spectrometer 64a, which is a mass separation area, is a mass separation area so that the ions 65b flying by the second flight distance L2 are incident on the second ion detection surface 63b. Type mass analyzer 64b.

The first ion detection surface 63a and the second ion detection surface 63b do not have to be opposed to each other. For example, in FIG. 6A, the second ion detection surface 63b may be provided on the surface next to the first ion detection surface 63a (surface in the direction perpendicular to the paper surface of FIG. 6A). In this case, the extraction electrode 62b is provided on the side of the ion source 61 in the direction perpendicular to the paper surface of FIG. 6A, and the quadrupole mass analyzer 64b is arranged rotated 90.degree. Just do it. In this way, the ions 65b emitted from the ion source 61 in the direction perpendicular to the paper surface of FIG. 6A pass through the quadrupole mass analyzer 64b, and the plane of the collector 63 in the direction perpendicular to the paper surface of FIG. It injects into the 2nd ion detection surface 63b provided in.

Thus, in the present embodiment, the first mass separation area (mass analyzer) that performs mass separation at the first flight distance L1 and the second mass that performs mass separation at the second flight distance L2 Since at least one of the separation region (mass analyzer) is formed in a non-linear manner, the ion current IL1 of the first flight distance L1 and the second The ion current IL2 of the flight distance L2 can be detected. It is preferable that the non-linear mass separation region be an arc-shaped mass separation region because the flight distance of ions can be easily obtained.

Fifth Embodiment
FIG. 7 is a view showing a mass spectrometer 1007 according to a fifth embodiment of the present invention. The mass spectrometer 1007 according to the present embodiment is a TOF (Time of fly) type mass spectrometer having one ion source, but the collector 73a is provided with an opening and some ions are Although captured and detected here, other ions pass through and are detected by the collector 73b. The distance L1 (first flight distance) from the ion source 71 to the collector 73a is 10 mm, and the distance L2 (second flight distance) from the ion source 71 to the collector 73b is 30 mm.

In FIG. 7, the TOF mass spectrometer 1007 includes an ion source 71, an extraction electrode 72 as a blanking electrode, a collector 73a spaced from the ion source 71 by a distance L1, and a distance from the ion source 71. And a collector 73b spaced apart by L2.

The TOF mass spectrometer generates ions intermittently to mass separate ions from the time they travel a certain distance. In the present embodiment, the collector 73a is provided to detect the ions flying from the ion source 71 by the flight distance L1. Therefore, the reference numeral 74a denotes a mass separation region in which mass separation is performed at the first flight distance L1. Become. Further, since the collector 73b is provided to detect the ions flying from the ion source 71 by the flight distance L2, reference numeral 74b is a mass separation area in which mass separation is performed at the second flight distance L2.

In this embodiment, a region between the ion emission surface of the ion source 71 and the ion detection surface of the collector 73a and through which the ions generated from the ion source 71 pass is a first movement path. Further, a region between the ion emission surface of the ion source 71 and the ion detection surface of the collector 73b and through which ions generated from the ion source 71 pass is a second movement path. Therefore, the TOF mass spectrometer 1007 detects the ion current IL1 (the first current value of the ion to be detected) at the end (collector 73a) of the first movement path. That is, the mass spectrometer 1007 detects the ion current IL1 which is the first ion current value from the measurement result of the current of the ions detected by the collector 73a. Also, the mass spectrometer 1007 detects the ion current IL2 (the second current value of the ion to be detected) at the end (collector 73b) of the second moving path, which is longer than the first moving path. That is, the mass spectrometer 1007 detects the ion current IL2 which is the second ion current value from the measurement result of the current of the ions detected by the collector 73b.

For intermittent generation of ions, the potential of the extraction electrode 72 is changed in a rectangular wave shape. In the case of a straight flight, the flight space has no electric field and no electrode is required.

In the present embodiment, the structure is the same as that of the second embodiment except that the mass spectrometer is configured as a TOF type, and all methods such as preliminary measurement / actual measurement / calculation are the same as the first embodiment. It is.
In the present embodiment, since the electrode (rod) is unnecessary, the configuration is simpler than in the second embodiment.

Sixth Embodiment
FIG. 8A is a view showing a mass spectrometer 1007 according to a sixth embodiment of the present invention. The mass spectrometer 1007 according to the present embodiment is a TOF (Time of Fly) type mass spectrometer having one ion source 81, but the flight area 84 of the ions is two sets of deflection rings 86a inside and outside, It is arc-shaped by 86b. In the present embodiment, as shown in FIG. 8B, a direct current (DC) power source is connected to the inner deflection ring 86a and the outer deflection ring 86b, and these inner deflection ring 86a and the outer deflection ring 86b are connected. By applying a predetermined DC voltage to the ions 85, the ions 85 fly in an arc shape.

Further, ions from the ion source 81 enter the circumferential orbit by the deflection electrode 87a for input, and after making a plurality of turns, are deviated from the circumferential orbit by the deflection electrode 87b for extraction and detected by the collector 83. Ru. The number of revolutions (that is, the flight distance (movement distance) of ions) can be arbitrarily determined by the timing of voltage application to the deflecting electrode 87b for extraction. That is, it is possible to adjust the flight distance (trajectory of ions) of ions by controlling the voltage applied to the deflection electrode 87a for injection and the deflection electrode 87b for extraction. Therefore, regardless of one ion source and one collector, mass analysis can be performed at substantially different flight distances.

For example, the first flight distance L1 is the flight distance of ions when the ions 85 travel around the flight region 84 once, and the second flight distance L2 is when the ions 85 travel around the flight region 84 three times. The flight distance of the ions.

At this time, when detecting the ion current of the ions flying by the first flight distance L1, the control unit 1000 applies a predetermined voltage to the deflection electrode 87a for injection to fly the ions 85 from the ion source 81. The mass spectrometer 1007 is controlled to be incident into the region 84. Next, the control unit 1000 applies a predetermined voltage to the deflecting electrode 87b for extraction when the ions 85 make one turn in the flight area 84 so that the ions 85 in the flight area 84 enter the collector 83. The mass spectrometer 1007 is controlled. In this manner, the collectors 83 detect the ions 85 emitted from the ion source 81 and flying for the first flight distance L1. At this time, since the ions 85 travel the first flight distance L1 in the flight area 84 and are detected by the collector 83, the first mass to be subjected to mass separation at the first flight distance is the flight area 84. It will function as a sorting area. In the present embodiment, the ions 85 generated from the ion source 81 pass through the circular flight space 84, which is an area between the deflection ring 86a and the deflection ring 86b, for changing the traveling direction of the ions a predetermined number of times. In the embodiment, the trajectory followed by the ions 85 when turning once and entering the collector 83 is the first movement path. The TOF mass spectrometer 1007 detects the ion current IL1 (the first current value of the ion to be detected) at the end (collector 83) of the first movement path.

On the other hand, when detecting the ion current of the ions flying by the second flight distance L2, the control unit 1000 applies a predetermined voltage to the deflection electrode 87a for input to make the ions 85 fly from the ion source 81 The mass spectrometer 1007 is controlled so as to be incident into 84. Next, the control unit 1000 applies a predetermined voltage to the deflecting electrode 87b for extraction at the timing when the ions 85 make three rounds in the flight area 84 so that the ions 85 in the flight area 84 enter the collector 83. The mass spectrometer 1007 is controlled. In this manner, the collectors 83 detect the ions 85 emitted from the ion source 81 and flying for the second flight distance L2. At this time, since the ions 85 travel the second flight distance L 2 in the flight area 84 and are detected by the collector 83, the second mass for which the flight area 84 performs mass separation at the second flight distance It will function as a sorting area. In the present embodiment, the ions 85 generated from the ion source 81 enter the collector 83 by turning the flight space 84 a number of times (three times in the present embodiment) more than at the time of the first current measurement. The trajectory followed by the ion 85 is the second movement path. The TOF mass spectrometer 1007 detects the ion current IL2 (the second current value of the ion to be detected) at the end (collector 83) of the second movement path.

As described above, in the present embodiment, the flight distance of the ions 85 is changed by the application timing of the voltage to the deflection electrode 87 a for input and the deflection electrode 87 b for extraction, so that the first flight distance and the second flight distance Detection of ion current by

The present embodiment has the same structure as that of the fifth embodiment except for the change of the flight distance, and the methods such as the preliminary measurement, the actual measurement, and the calculation are all the same as the first embodiment.
In the present embodiment, since one ion source and one collector are provided, the configuration is simpler than in the fifth embodiment.

(Other embodiments)
The present invention is not limited to the calculation formula in the above embodiment in the calculation of the original ion current, but an expression obtained by adding a correction term (experimental formula) obtained empirically based on this calculation formula. It can also be used.

Although the "deviation" from an ideal state always occurs, the "deviation" is often the same if the related conditions (ion current, ion energy, ion species, etc.) are the same. Therefore, it is possible to obtain a calculation formula which measures this "deviation" experimentally (empirically) and corrects it, that is, a calculation formula including an empirical formula (correction term). Furthermore, since the correction term depends on the related condition, it is possible to obtain a function (for example, empirical formulas F and G) of the correction term with the related condition as a variable by conducting experiments under several conditions It becomes. This can be used to make more accurate measurements.

The present invention can measure not only the atmosphere gas in which the device is installed but also the atmosphere gas in a different (independent) region from the atmosphere in which the device is installed. . For this purpose, the gas to be measured may be introduced into the ion source of the present apparatus through piping or a capillary. In this case, although the atmosphere for attenuating the ion current is not an object to be measured, the original ion current can be calculated by the same method as the above embodiment.

The present invention can measure not only the gas that is neutral but also ions that are initially charged. For example, since ions are present as they are in plasma or the like, the case of measuring ion density of plasma or the like is this example. In this case, it is not necessary to set the ion source on the mass spectrometer side, and the location of ion generation such as plasma may be considered as the location of the ion source in the above embodiment.

(Still other embodiments)
The present invention can be applied to a system comprising a plurality of devices (for example, a computer, an interface device, a reader, a printer, a mass spectrometer 1007, etc.) or to an apparatus comprising a single device.

A process for storing a program for operating the configuration of the above-described embodiment to realize the function of the control unit 1000 of the above-described embodiment in a storage medium, reading the program stored in the storage medium as a code, and executing it on a computer Methods are also included within the scope of the embodiments described above. That is, a computer readable storage medium is also included in the scope of the embodiments. Further, not only the storage medium in which the above-described computer program is stored but also the computer program itself is included in the above-described embodiment.

As such a storage medium, for example, a floppy (registered trademark) disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a non-volatile memory card, and a ROM can be used.

Also, the present invention is not limited to the execution of processing by a single program stored in the storage medium described above, but also runs on the OS in cooperation with other software and the function of the expansion board to execute the operation of the above-described embodiment Are included in the scope of the above-described embodiment.

Claims (16)

1. An ion source,
   A second current value of a specific ion is detected at the end of a first moving path for passing ions generated by the ion generation source, and the second ion passing path is longer than the first moving path. Detection means for detecting a second current value of the particular ion at the end of the movement path;
   Calculation means for calculating the abundance of the specific ion generated in the ion generation source from the first and second current values;
   First mass separation means for passing only the specific ions in at least a part of the first movement path;
   And a second mass separation unit that allows only the specific ions to pass through at least a part of the second movement path.
2. The ion source is an ion source that ionizes an atmosphere gas,
   The mass spectrometer according to claim 1, wherein the amount of the atmosphere gas is measured.
3. The mass spectrometer according to claim 2, wherein two of the ion sources are provided in the same atmosphere gas.
4. 4. The apparatus according to claim 3, wherein said detection means is one detection means which is used as both the detection means for detecting the first current value and the detection means for detecting the second current value. Mass spectrometer.
5. The mass spectrometer according to claim 1, wherein at least one of the first movement path and the second movement path is non-linear.
6. The detection means is a detector for detecting ions, and is configured such that ions are incident on the detector at the end of the first moving path, and the ions are detected at the end of the second moving path. The mass spectrometer according to claim 1, wherein the mass spectrometer is configured to be incident on the detector.
7. The detector is a single detection means that combines the detection means for detecting the first current value and the detection means for detecting the second current value, and the first ion detection surface and the first ion detection surface And a second ion detection surface different from the first ion detection surface,
   The detector is configured such that ions are incident on the first ion detection surface at the end of the first movement path, and ions are detected at the end of the second movement path. The mass spectrometer according to claim 6, characterized in that it is configured to be incident on.
8. The mass spectrometer according to claim 1, wherein the first movement path constitutes a part of the second movement path.
9. The mass spectrometer according to claim 1, wherein each of the first and second movement paths has an arc shape.
10. 10. The mass spectrometer according to claim 9, wherein the first and second movement paths in the form of arcs have the same diameter and the same center point.
11. The detection means
    A detector for detecting the specific ion;
    The length of the first movement path and the length of the second movement path may be adjusted by adjusting the movement distance of the specific ion from the ion source to the detector.
    The mass spectrometer according to claim 1, wherein the detector detects the first and second current values by changing the movement distance of the specific ion by the adjusting unit.
12. The detection means
    A first detector for detecting ions at the end of the first movement path;
    And a second detector for detecting ions at the end of the second movement path,
    The first detector according to claim 1, wherein the first detector is a detector configured to detect a part of the reached ions and pass another part of the ions as it is. Mass spectrometer.
13. The detection means sets the ion current in the case of not being attenuated to I0, the length of the first movement path to L1, the length of the second movement path to L2, and the first current value A step of substituting the first and second current values into the equation L1 / Loge (IL1 / I0) = L2 / Loge (IL2 / I0) where IL1 is the second current value IL2. The mass spectrometer according to claim 1, wherein the abundance is calculated by performing
14. A mass spectrometry method for measuring the abundance of specific ions, comprising
    Generating the specific ion from an ion source;
    A first current value of the specific ion moved by a first movement distance from the ion generation source and detected by mass separation is detected, and a second movement distance longer than the first movement distance from the ion generation source is detected. Detecting a second current of the particular ion which has moved and mass separated;
    Calculating the abundance of the specific ion from the detected first and second currents.
15. Computer,
    A first current value of a specific ion is detected at an end of a first movement path for passing ions generated by the ion generation source and the ion generation source, and the ion longer than the first movement path is detected A control unit of a mass spectrometer comprising: detection means for detecting a second current value of the specific ion at the end of a second movement path to be passed through;
    A control unit configured to control the ion generation source to generate the specific ion, and to cause the detection unit to detect the first and second current values;
    Means for acquiring the first current value and the second current value;
    A computer program that functions as a control device, comprising: means for calculating the abundance of the specific ion from the first and second current values.
16. A storage medium storing a computer readable program, wherein the computer program according to claim 15 is stored.

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