JP5430908B2 - Spectroscopic analyzer - Google Patents

Description

  The present invention relates to a spectroscopic analyzer suitable for analyzing an insulating sample.

  An X-ray photoelectron spectroscopic analyzer, which is one of the spectroscopic analyzers, irradiates a sample to be analyzed with X-rays so that the photoelectrons emitted from the sample are decelerated and focused by an input lens and incident on an analyzer. Photoelectrons are subjected to energy spectroscopy with the analyzer to obtain an energy spectrum of the sample, and quantitative analysis of elements contained in the sample is performed from the energy spectrum.

  In such an X-ray photoelectron spectroscopic analyzer, when analyzing a sample made of an insulator, photoelectrons are emitted from the sample surface by X-ray irradiation to the sample surface. To do. When such charging occurs, the kinetic energy of the photoelectrons emitted from the sample changes due to the potential difference between the sample and the detector, and the resulting photoelectron energy spectrum shifts with respect to the bound energy axis (electron kinetic energy axis). (Shift to high binding energy side), making it difficult to perform accurate analysis.

  Therefore, for example, a neutralized electron gun is used to irradiate a positively charged sample surface with an electron beam to electrically neutralize the charge charged on the sample surface.

  FIG. 1 shows a schematic example of an X-ray photoelectron spectrometer equipped with a neutralizing electron gun.

  In the figure, 1 is an X-ray generation source, 2 is a sample irradiated with the X-ray 3 from the X-ray generation source, 4 is a sample stage on which the sample is placed, and 6 is a sample charged by irradiation with the X-ray 3. 2 A neutralizing electron gun for irradiating an electron beam for neutralizing the surface, 7 is a photoelectron spectrometer, an input lens 7a, and photoelectrons from the sample 2 incident through the input lens 5 includes an analyzer 7b composed of an inner hemispherical electrode and an outer hemispherical electrode for energy analysis, and a detector 7c for detecting photoelectrons subjected to energy selection by the analyzer.

  8 is an amplifier for amplifying the output signal of the detector 7c, and 9 is an AD converter.

  Reference numeral 10 denotes a control device that controls each means constituting the photoelectron spectrometer and performs various arithmetic processes.

  Reference numeral 11 denotes an X-ray generation source control power source for sending a control signal to the X-ray generation source 1 based on a command from the control device 10, and reference numeral 12 denotes the input lens 7a and the analyzer 7b based on a command from the control device 10. A control power source 13 sends a control signal to the neutralizing electron gun 13 and sends a control signal to the neutralizing electron gun 6 based on a command from the control device 10.

  Reference numeral 14 denotes a storage device for storing the output signal (photoelectron energy spectrum signal) of the detector 7c, and reference numeral 15 denotes the photoelectron energy spectrum signal read from the storage device 14 based on a command from the control device 10. A display device 16 is an input device including a mouse, a keyboard, and the like.

  In the X-ray photoelectron spectrometer having such a configuration, when a control signal is sent from the X-ray generation source control power supply 11 to the X-ray generation source 1 according to a command from the control device 10, the X-ray generation source emits X-rays 3. Occur. The surface of the sample 2 is irradiated with the X-rays, and photoelectrons 5 are emitted from the sample.

  At this time, when the sample 2 is a sample made of an insulating material (insulating sample), when the photoelectrons 5 are emitted from the surface of the insulating sample, the X-ray irradiation region on the surface of the sample is positively charged.

  At the same time, a control signal is sent from the neutralizing electron gun control power supply 13 to the neutralizing electron gun 6 in accordance with a command from the control device 10, and the X-ray irradiation on the surface of the sample 2 is performed from the neutralizing electron gun. By irradiating the region with the electron beam, the positively charged electric charge in the X-ray irradiation region is electrically neutralized.

  Then, the photoelectrons 6 emitted from the surface of the sample 2 enter the input lens 7a, where they are decelerated and focused, enter the analyzer 7b, undergo energy spectroscopy in the analyzer, and are detected by the detector 7c.

  The output signal of the detector is sent to the control device 10 via the amplifier 8 and the AD converter 9 and stored in the storage device 14 as a photoelectron energy spectrum signal.

  The control device 10 reads out the photoelectron energy spectrum signal from the storage device 14 and sends it to the display device 15 to display the photoelectron energy spectrum on the display screen of the display device.

  However, since the spatial intensity distribution of the X-rays 3 generated from the X-ray generation source 1 is strong in the central part and weak in the peripheral part, the central part in the X-ray irradiation region is charged more than the peripheral part. In many cases, a non-uniform charging state occurs in the X-ray irradiation region.

  In addition, a non-uniform charging state depending on the sample surface shape occurs in the X-ray irradiation region. For example, the convex portion on the sample surface has a larger amount of charge than other portions, and a non-uniform charged state occurs in the X-ray irradiation region.

  When a non-uniform charging state occurs on the sample surface in this manner, the non-uniform charging state on the sample surface is not eliminated even when the electron beam is uniformly irradiated from the neutralizing electron gun 6 to the sample surface.

  If there is such a non-uniform charged state, the spectrum is deformed by the superposition of the spectra having different shift amounts, or the peak width is widened, making it difficult to accurately analyze the sample.

JP-A-7-183343

  In order to solve such problems, the present inventor made the following proposal and filed a patent application (Japanese Patent Application No. 2007-232123) on September 7, 2007.

  That is, if the non-uniform charged state on the sample surface is first made uniform, and the charged sample surface is irradiated with charged particles opposite in polarity to the charged surface, the charge on the sample surface is neutralized. For example, an appropriate positive bias voltage is applied to the sample stage on which the sample irradiated with the electron beam from the neutralizing electron gun is placed on the surface of the sample positively charged by X-ray irradiation. When applied, at least the entire stage contact surface of the sample is uniformly charged, for example, positively, and charged particles (electrons) having a polarity (positive) opposite to the polarity (positive) of the charged charge on the surface of the sample. Was applied to uniformly neutralize the charge on the sample surface.

  FIG. 2 shows a schematic example of an X-ray photoelectron spectroscopic analyzer based on such a principle. In FIG. 2, the same reference numerals as those used in FIG. 1 denote the same components.

  In the figure, 21 is a bias voltage power source for applying a positive bias voltage to the sample 2 in accordance with a command from the control device 10, 22 is a peak position reading device for reading the peak position (peak energy value) of the obtained energy spectrum, and 23 is the above reading. A memory that stores the peak positions in association with the bias voltage, 24 is a first arithmetic unit that calculates a difference between the peak positions in the order of reading, and 25 is a time when the difference is continuously within the allowable range. A second arithmetic unit 25a for obtaining a bias voltage value is a counting unit provided in the second arithmetic unit 25, which counts once every time the difference falls within an allowable value range.

  In the X-ray photoelectron spectrometer having such a configuration, first, the peak used for obtaining the bias voltage from the photoelectron energy spectrum of the sample 2 displayed on the display screen of the display device 15 is designated as follows.

  The sample 2 to be analyzed is an insulating sample, for example, a film made of PET (polyethylene terephthalate resin). The energy spectrum of the carbon atom 1s orbit obtained by X-ray photoelectron spectroscopic analysis of the surface has three peaks P1, P2, and P3 as shown by the broken line S1 in FIG. Among them, the peak (P1) whose peak position (peak energy value) is near 285 eV corresponds to the C—C bond, the peak near 286.5 eV (P2) corresponds to the C—O bond, and the peak near 289 eV ( P3) is considered to correspond to the O—C═O bond, but the peak P3 with less interference between peaks is designated as the peak used for obtaining the bias voltage.

  Further, the operator is required to determine the upper limit voltage value and lower limit voltage value of the bias voltage to be applied to the sample 2 and the variable width of the voltage, the specified peak, and the bias voltage value to be applied to the sample 2 by the input device 16. The allowable range is input to the control device 10.

  The control device stores the upper limit voltage value, the lower limit voltage value, and the variable width of the voltage in the storage device 14, sets the designated peak in the peak position reading device 22, and further sets the allowable value range to the second arithmetic device 25. Set to.

  Now, when X-rays 3 are irradiated from the X-ray generation source 1 to a predetermined location on the sample 2, photoelectrons 5 are emitted from the sample, and the sample is positively charged. At this time, at the same time, a control signal is sent from the neutralizing electron gun control power supply 13 to the neutralizing electron gun 6 according to a command from the control device 10, and electrons are transferred from the neutralizing electron gun to the X-ray irradiation region on the surface of the sample 2. The beam is irradiated, and the charging of the irradiated area is neutralized.

  At this time, the upper limit voltage value, the lower limit voltage value, and the variable width of the voltage are read from the storage device 14 based on a command from the control device 10 and sent to the bias voltage power source 21.

  Then, the power source changes the bias voltage to the sample stage 4 at a predetermined time interval with a variable width (for example, 5 V) set from a lower limit value (for example, 0 V) to an upper limit value (for example, 30 V).

  Then, each time the bias voltage is applied, the photoelectrons 5 emitted from the surface of the sample 2 are dispersed by the photoelectron spectrometer 7 and detected by the detector 7c. The output of the detector 7c is an amplifier 8 and an AD converter 9 Is sent to the control device 10 as a photoelectron energy spectrum signal, and is temporarily stored in the storage device 14 in association with each bias voltage.

  Next, the peak position reading device 22 reads photoelectron energy spectrum signals from the storage device 14 via the control device 10 in the order of measurement, and the peak of the designated peak of each measured photoelectron energy spectrum based on the designated peak. Read the position (peak energy value).

  Here, when the reference peak position of the designated peak P3 is 289 (eV), the relationship between the designated peak position read from each photoelectron energy spectrum of the sample obtained for each bias voltage and the bias voltage is shown in FIG.

  From the relationship between the bias voltage and the peak position shown in FIG. 4, in the case of this sample, the peak position fluctuates from 0 V to around 9 V, but the fluctuation of the peak position is small and almost constant at 10 V or more. I understand.

  The fact that the fluctuation of the peak position is constant corresponds to that the charged state (for example, positive charged state) of the sample surface is uniform.

  That is, by applying a bias voltage of 10 V or more to the sample, an energy spectrum when the charged state of the sample surface is uniform can be obtained.

  Next, a specific method for obtaining the bias voltage value to be set will be described.

  The peak position reader 22 stores the read peak position of each photoelectron energy spectrum in the memory 23 in the order of measurement.

  Then, the first arithmetic unit 24 reads each peak position from the memory, obtains a difference between the peak positions in the order of measurement, and sends it to the second arithmetic unit 25 in association with the bias voltage.

  The second arithmetic unit sequentially determines whether or not each difference value from the first arithmetic unit 24 for each bias voltage is within the preset allowable value range, and the difference value is an allowable value. When entering, the counting unit 25a counts once. At this time, the count unit adds the count number when the difference value continuously enters the allowable value range, and resets the count number when the difference value does not continuously enter the allowable value range.

  The count section is preset with the number of times that the set bias voltage is determined.

  When the count number of the count unit reaches the set number, the bias voltage value for the difference value at that time is determined as the bias voltage to be set.

  The second arithmetic unit 25 stores the bias voltage Vs thus determined in the storage device 14 via the control device 10.

  Next, the control device 10 reads the set bias voltage Vs from the storage device 14 and sends a command to the bias voltage power source 21 so that the voltage Vs is applied to the sample stage 4.

At the same time, the X-ray 3 from the X-ray generation source 1 and the electron beam from the neutralizing electron gun 6 are irradiated to the same portion of the sample 2.
At this time, the acceleration voltage of the neutralizing electron gun 6 corresponds to the bias voltage value so that the sample surface is uniformly neutralized by the application of the bias voltage Vs and the electron beam from the neutralizing electron gun 6. Let's control.

  Photoelectrons 5 are emitted from the X-ray irradiation spot on the sample 2, and the photoelectrons enter the input lens 7a, decelerate and converge by an electrostatic lens (not shown), and enter the analyzer 7b. The incident photoelectrons are subjected to energy spectroscopy in the analyzer and detected by the detector 7c.

  The output signal of the detector is sent to the control device 10 via the amplifier 8 and the AD converter 9, and the control device causes the display device 15 to display the photoelectron energy spectrum.

  S2 of FIG. 3 shows the photoelectron energy spectrum of the 1s orbit of the carbon atom of the PET film displayed on the display screen of the display device.

  As can be seen from this spectrum S2, according to this embodiment, even if the X-ray intensity distribution of the X-ray source is not uniform or the sample surface is uneven, the charge on the sample surface is charged. Is almost neutralized, and the energy spectrum S2 obtained by the electron spectroscopic analysis method of this example has a small spectral deformation even when compared with the photoelectron energy spectrum S1 obtained under the influence of the conventional sample charging. In addition, the spread of the peak width is small.

  However, it has been found that the bias voltage applied to the sample stage may not be required depending on the state of electrons emitted from the neutralizing electron gun 6.

  That is, when the neutralizing electron gun 6 that emits an electron with a relatively small energy is used, or when the neutralizing electron gun is adjusted so as to emit an electron with a very small energy, the bias The relationship between the voltage and the peak position does not become as shown in FIG. 4 (the peak position fluctuates from 0 V to around 9 V, but the fluctuation of the peak position is small and almost constant when the bias voltage is 10 V or more). As shown in FIG. 5, it was found that the peak position did not become constant after 10 V and gradually increased.

  In such a case, the bias voltage applied to the sample stage cannot be obtained, and as a result, the sample cannot be analyzed accurately.

  The present invention has been made to solve such problems, and an object thereof is to provide a novel spectroscopic analyzer.

Simultaneously irradiating the sample surface with the radiation beam, the charged particle beam from the neutralized charged particle beam generating means is irradiated onto the sample surface, and the secondary charged particles emitted from the sample surface based on the radiation beam irradiation are irradiated. An apparatus that is guided to an energy analyzer and obtains an energy spectrum by performing energy spectroscopy with the energy analyzer, and applying a bias voltage to a sample stage on which the sample is set makes the surface of the sample uniform. In the spectroscopic analyzer configured to be charged, a shielding member made of a conductive material provided so as to cover the sample stage with respect to the neutralized charged particle beam generating means, the radiation beam, neutralizing charged particle beam, the secondary charged particles can pass holes provided, and is provided with a shielding member that is grounded, before The shielding member is formed in a container shape so that the sample stage is disposed therein, the hole is provided in a central portion of the upper wall facing the sample setting surface of the stage, and Characterized by being electrically insulated from the sample

  According to the present invention, even when a neutralized charged particle beam generator that emits charged particles with a relatively low energy is used, or so that charged particles with a considerably low energy can be emitted, Even when the charged particle beam generator is adjusted, the bias voltage applied to the sample stage is obtained, and as a result, the sample can be analyzed accurately.

  The present inventor uses the neutralizing electron gun 6 that emits electrons with a relatively small energy, or the energy of electrons emitted from the neutralizing electron gun becomes considerably small. When the neutralizing electron gun is adjusted in this way, the relationship between the bias voltage and the peak position is as shown in FIG. 4 (the peak position varies from 0 V to around 9 V, but the peak position is greater than 10 V. As shown in FIG. 5, the cause of the peak position gradually increasing after 10V was searched and the following conclusion was obtained.

  When a positive bias voltage is applied to the sample stage and the sample stage is at a positive potential, the electron beam directed from the neutralizing electron gun toward the sample is applied to the sample on the sample mounting surface of the sample stage. There is a possibility of being influenced by a positive potential (that is, an influence (deflection) due to a positive electric field based on the positive potential) of the peripheral portion not in contact. In this case, the influence force (deflection force) received by the electrons from the neutralizing electron gun depends on the magnitude of its own energy and the strength of the bias voltage. The smaller the energy, the greater the bias voltage value. The force (deflection force) is large.

  Therefore, if the energy of electrons from the neutralizing electron gun is considerably small, the influence of the positive potential on the peripheral portion of the sample stage that is not in contact with the sample (based on the positive potential) The electron beam trajectory toward the sample is greatly bent in the direction of the peripheral portion, and the irradiation position of the electron beam on the sample deviates from the X-ray irradiation region. Also occurs.

  In such a case, since the X irradiation region is the same as the state in which the electrons from the neutralizing electron gun are not irradiated, the spatial intensity of the X-ray 3 generated from the X-ray generation source 1 is present in the X irradiation region. A non-uniform charge state is generated based on the uneven distribution and the sample surface shape of the X irradiation region. Therefore, in such a case, it is considered that the charged state (for example, positive charged state) of the X irradiation region does not become uniform, and the relationship between the bias voltage and the peak position becomes as shown in FIG. .

  Accordingly, the present inventor has found that even when a predetermined bias voltage is applied to the sample stage, the positive potential (positive electric field based on the positive potential) at the peripheral portion of the sample mounting surface based on the bias voltage is generated from the neutralizing electron gun. For example, if the positive electric field based on the positive potential of the peripheral part of the sample mounting surface is cut off from the electron coming from the neutralizing electron gun toward the sample surface, I thought the problem would be solved.

FIG. 6 shows a schematic example of a spectroscopic analyzer made on the basis of such a principle, and components having the same symbols as those used in FIG. 2 indicate the same components.

  The description will focus on the configuration of the apparatus shown in FIG. 6 different from the apparatus shown in FIG.

  In the apparatus shown in FIG. 6, the sample stage 4 is arranged inside a rectangular parallelepiped container 31 formed of a conductive material.

  The sample stage 4 is fixed on the bottom wall 31a of the container via supports 32a and 32b formed of an insulating material.

  Further, a hole 33 through which a cable for electrically connecting the bias power source 21 and the stage 4 is formed in one side wall 31b of the container.

  Further, the X-ray from the X-ray generation source 1 can irradiate the sample 2 on the center of the upper wall 31c of the container, and photoelectrons generated from the sample by the X-ray irradiation can enter the input lens 7a, and A hole 34 through which electrons from the neutralizing electron gun 6 can be irradiated to the sample is formed.

  Thus, the hole 3 allows passage of the X-rays, photoelectrons and electrons, and the periphery of the sample mounting surface based on the bias voltage applied to the sample stage 4 that is not in contact with the sample. In view of the electron emission portion of the neutralizing electron gun 6, the sample mounting is performed so that the positive potential of the portion (positive electric field based on the positive potential) does not affect the electrons from the neutralizing electron gun 6. The placement surface peripheral portion is opened so as to have a diameter that is hidden by the upper wall 31c.

  In the X-ray photoelectron spectroscopic analyzer having such a configuration, a sample 2 to be analyzed (for example, a film made of PET (polyethylene terephthalate resin)) is set on the sample stage 4 and a photoelectron energy spectrum is measured in advance. From the photoelectron energy spectrum (S1 in FIG. 3) of the sample 2 displayed on the 15 display screen, the peak P3 with less interference between peaks is designated as the peak used for obtaining the bias voltage.

  Further, the operator is required to determine the upper limit voltage value and lower limit voltage value of the bias voltage to be applied to the sample 2 and the variable width of the voltage, the designated peak, and the bias voltage value to be applied to the sample by the input device 16. The allowable range is input to the control device 10.

  The control device stores the upper limit voltage value, the lower limit voltage value, and the variable width of the voltage in the storage device 14, sets the designated peak in the peak position reading device 22, and further sets the allowable value range to the second arithmetic device 25. Set to.

  Now, when X-rays 3 are irradiated from the X-ray generation source 1 to a predetermined location on the sample 2, photoelectrons 5 are emitted from the sample, and the sample is positively charged. At this time, at the same time, a control signal is sent from the neutralizing electron gun control power supply 13 to the neutralizing electron gun 6 according to a command from the control device 10, and electrons are transferred from the neutralizing electron gun to the X-ray irradiation region on the surface of the sample 2. The beam is irradiated, and the charging of the irradiated area is neutralized. At this time, it is assumed that the X-ray irradiation region is unevenly charged due to the spatial intensity distribution of the X-ray 3 and the surface shape of the X-ray irradiation region.

  At this time, the upper limit voltage value, the lower limit voltage value, and the variable width of the voltage are read from the storage device 14 based on a command from the control device 10 and sent to the bias voltage power source 21.

  Then, the power source changes the bias voltage to the sample stage 4 at a predetermined time interval with a variable width (for example, 5 V) set from a lower limit value (for example, 0 V) to an upper limit value (for example, 30 V).

  By applying this bias voltage, the sample stage 4 becomes a positive potential, but the electric field based on the positive potential of the peripheral portion not contacting the sample in the sample mounting surface of the sample stage is the upper wall portion 31c of the container 31. Thus, the upward leakage of the upper wall portion is shielded, and the electrons from the neutralizing electron gun 6 are not electrically affected (deflecting force). Accordingly, the electron from the neutralizing electron gun 6 is irradiated to the X-ray irradiation region without the trajectory being bent by the electric field.

  The photoelectrons 5 emitted from the surface of the sample 2 each time the bias voltage is applied in this way are dispersed by the photoelectron spectrometer 7 and detected by the detector 7c, and the output of the detector 7c is an amplifier 8, AD It is sent to the control device 10 as a photoelectron energy spectrum signal through the converter 9 and temporarily stored in the storage device 14 in association with each bias voltage.

  Next, the peak position reading device 22 reads photoelectron energy spectrum signals from the storage device 14 via the control device 10 in the order of measurement, and the peak of the designated peak of each measured photoelectron energy spectrum based on the designated peak. Read the position (peak energy value).

  Here, when the reference peak position of the designated peak P3 is 289 (eV), the relationship between the designated peak position read from each photoelectron energy spectrum of the sample obtained for each bias voltage and the bias voltage is shown in FIG.

  From the relationship between the bias voltage and the peak position shown in FIG. 7, in the case of this sample, the peak position fluctuates from 0 V to around 10 V, but the fluctuation of the peak position is small and almost constant at 10 V or more. I understand.

  The fact that the fluctuation of the peak position is constant corresponds to that the charged state (for example, positive charged state) of the sample surface is uniform.

  That is, by applying a bias voltage of 10 V or more to the sample, an energy spectrum when the charged state of the sample surface is uniform can be obtained.

  Next, the bias voltage value to be set is specifically obtained. This calculation method is the same as the calculation method (determined by the peak position reading device 22, the memory 23, the first calculation device 24, and the second calculation device 25) in the X-ray photoelectron spectrometer shown in FIG. So, I will not explain it here again.

  Next, the bias voltage Vs ′ obtained in this way is stored in the storage device 14 from the second arithmetic device 25 via the control device 10.

  Next, the control device 10 reads the set bias voltage Vs ′ from the storage device 14 and sends a command to the bias voltage power supply 21 so that the voltage Vs ′ is applied to the sample stage 4.

At the same time, the X-ray 3 from the X-ray generation source 1 and the electron beam from the neutralizing electron gun 6 are irradiated to the same portion of the sample 2.
At this time, the acceleration voltage of the neutralizing electron gun 6 is set to the bias voltage value so that the sample surface is uniformly neutralized by the application of the bias voltage Vs ′ and the electron beam from the neutralizing electron gun 6. It is controlled in correspondence.

  Photoelectrons 5 are emitted from the X-ray irradiation spot on the sample 2, and the photoelectrons enter the input lens 7a, decelerate and converge by an electrostatic lens (not shown), and enter the analyzer 7b. The incident photoelectrons are subjected to energy spectroscopy in the analyzer and detected by the detector 7c.

  The output signal of the detector is sent to the control device 10 via the amplifier 8 and the AD converter 8, and the control device causes the display device 15 to display the photoelectron energy spectrum.

S2 of FIG. 3 shows the photoelectron energy spectrum of the 1s orbit of the carbon atom of the PET film displayed on the display screen of the display device.

  Although not particularly shown in the above example, a rectangular parallelepiped container 31 made of a conductive material having the sample stage 4 disposed therein and grounded is provided in the sample chamber, for example, on the bottom wall of the chamber. . On the other hand, in order to prevent the electric field based on the positive charge in the peripheral portion not in contact with the sample in the sample mounting surface of the sample stage from affecting the electrons from the neutralizing electron gun 6 at all, A shielding object made of a grounded conductive material may be present between the electric field and the neutralizing electron gun 6. Therefore, the shielding object may not be limited to the container shape. For example, a cover having a bottom wall removed from the container may be used. However, in this case, a base plate that contacts the bottom wall of the container is provided on the bottom wall of the sample chamber, and the sample stage is supported on the base plate via a support made of an insulating material.

Moreover, the X-ray from the X-ray generation source 1 can be irradiated on the sample 2 at the center of the shielding object,
A fixed hole 34 through which photoelectrons generated from the sample by the X-ray irradiation can enter the input lens 7a and electrons from the neutralizing electron gun 6 can be irradiated to the sample.
However, a plurality of shielding objects having different sizes of the holes 34 are produced,
In order to sufficiently shield the surface other than the sample placement on the sample stage 4, a shielding object having a hole corresponding to the size of the sample may be selectively attached.

Further, a mechanism that can change the size of the hole 34 in the central portion of the shielding object may be provided. 8 and 9 show an example of such an embodiment. FIG.
(A) and FIG. 9 are schematic views in which a stop mechanism is incorporated in a shielded object shown as an example of the embodiment, and FIG. 8 (b) is a cross-sectional view of FIG. 8 (a).

8 (a) and 8 (b), an iris diaphragm mechanism 40 that creates a hole 39 of each size by superimposing a number of wings 38 made of a conductive material on the center of the upper wall shielding plate 31C of the container 31. Is provided. The plurality of wings of the iris diaphragm mechanism 40 and the shielding object are electrically connected and grounded.

In the present embodiment, since the hole 39 formed by the iris diaphragm mechanism 40 can be varied in accordance with the size of the sample 2 ′ to be analyzed, the insulating sample can be accurately analyzed.

In FIG. 9, a rectangular opening 41 indicated by a broken line is provided at the center of the upper wall shielding plate 31c of the container 31, and two L-shaped plates 42 made of a conductive material are provided on the opening.
43 is arranged in a rotationally symmetrical manner, and an L-shaped plate slide mechanism 45 that can change the size of the rectangular opening 44 is provided by moving the two L-shaped plates up, down, left, and right with respect to the paper surface. Yes. The two L-shaped plates 42 and 43 and the shielding plate 31
C is electrically connected and grounded.

In the present embodiment, for example, when the sample to be analyzed is a sample 2 ′ having a size as indicated by a broken line, the L-shaped plate slide mechanism 45 slides the L-shaped plates 42, 43 up and down and left and right. Since the opening can be adjusted to the size of the sample 2 ′, the insulating sample can be accurately analyzed.

  In the above example, the neutralization electron gun 6 is used as an example. However, when the sample surface is negatively charged, the neutralization ion gun is used. A bias voltage may be set to control the neutralizing ion gun.

  Further, as shown by a broken line in FIG. 6, a neutralizing ion gun 35 is provided in addition to the neutralizing electron gun 6, and the neutralizing electron gun 6 and the neutralizing ion gun 35 according to the polarity of charge on the sample surface. May be used properly.

1 is a schematic example of a conventional X-ray photoelectron spectrometer. 1 shows a schematic example of an X-ray photoelectron spectroscopic analyzer that implements the invention proposed in advance by the present inventor. The photoelectron energy spectrum of the 1s orbit of the carbon atom of a PET film is shown. 3 shows a relationship between a bias voltage and a designated peak position (designated peak energy value) in spectroscopic analysis with the apparatus shown in FIG. FIG. 3 shows a relationship between a bias voltage and a designated peak position indicating a defect in spectroscopic analysis in the apparatus shown in FIG. 2. 1 shows a schematic example of a spectroscopic analyzer of the present invention. 3 shows a relationship between a bias voltage and a designated peak position in spectroscopic analysis in the spectroscopic analysis apparatus of the present invention. 1 shows a schematic example in which a diaphragm mechanism is incorporated in the shielding object of the present invention. It shows another schematic example in which a diaphragm mechanism is incorporated in the shielding object of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... X-ray generation source 2, 2 '... Sample 3 ... X-ray 4 ... Sample stage 5 ... Photoelectron 6 ... Neutralization electron gun 7 ... Photoelectron spectrometer 8 ... Amplifier 9 ... AD converter 10 ... Control apparatus 11 ... X Line source control power supply 12 ... Control power supply 13 ... Neutralizing electron gun control power supply 14 ... Storage device 15 ... Display device 16 ... Input device 17 ... Input device 22 ... Peak position reading device 23 ... Memory 24 ... First arithmetic unit 25 ... 2nd arithmetic unit 25a ... Count part 31 ... Container 31a ... Bottom wall 31b ... Side wall 31c ... Upper wall 32a, 32b ... Support body 33, 34 ... Hole 36 ... Shielding plate 37, 39 ... Hole 38 ... Wing 40 ... Iris diaphragm Mechanism 41 ... Opening 42, 43 ... L-shaped plate 44 ... Opening 45 ... L-shaped plate slide mechanism

Claims (3)

Simultaneously irradiating the sample surface with the radiation beam, the charged particle beam from the neutralized charged particle beam generating means is irradiated onto the sample surface, and the secondary charged particles emitted from the sample surface based on the radiation beam irradiation are irradiated. An apparatus that is guided to an energy analyzer and obtains an energy spectrum by performing energy spectroscopy with the energy analyzer, and applying a bias voltage to a sample stage on which the sample is set makes the surface of the sample uniform. In the spectroscopic analyzer configured to be charged, a shielding member made of a conductive material provided so as to cover the sample stage with respect to the neutralized charged particle beam generating means, the radiation beam, neutralizing charged particle beam, the secondary charged particles can pass holes provided, and is provided with a shielding member that is grounded, before The shielding member is formed in a container shape so that the sample stage is disposed therein, the hole is provided in a central portion of the upper wall facing the sample setting surface of the stage, and A spectroscopic analyzer characterized in that it is electrically insulated from a sample . The spectroscopic analyzer according to claim 1, further comprising a mechanism for changing the size of the hole. The spectroscopic analysis apparatus according to claim 1, wherein the radiation beam is an X-ray, and the charged particle beam generating means is an electron beam generating means and / or an ion beam generating means.

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