JP2010048584A - X-ray photoelectron spectrometer, total reflection x-ray photoelectron spectrometer and angle-resolved x-ray photoelectron spectrometer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray photoelectron spectrometer and a total reflection X-ray photoelectron spectrometer capable of analyzing a sample with high accuracy by flattening the sample surface. <P>SOLUTION: The X-ray photoelectron spectrometer comprises: an etching means for etching the sample surface by a charged drop etching method; an X-ray irradiation means for irradiating the etched surface of the sample with X-ray radiation at an angle less than the total reflection critical angle satisfying the total reflection condition; and an analysis means for performing a depth direction analysis around the sample surface by analyzing photoelectrons emitted from the sample surface irradiated with X-ray radiation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an X-ray photoelectron spectrometer, a total reflection X-ray photoelectron spectrometer, and an angle-resolved X-ray photoelectron spectrometer, and more specifically, an X-ray photoelectron spectrometer and a total reflection X capable of performing X-ray photoelectron spectroscopy with high accuracy. The present invention relates to a line photoelectron spectrometer and an angle-resolved X-ray photoelectron spectrometer. The present invention provides sample surface flattening for surface sensitive measurement of polymer materials, transition metal oxides, semiconductor materials, etc. in surface analysis equipment (XPS: X-ray photoelectron spectrometer, etc.), and TRXPS: total reflection X-ray photoelectron spectroscopy. Device, ARXPS: relates to the measurement field of depth direction analysis combined with an angle-resolved X-ray photoelectron spectrometer. In particular, it is expected to be applied to semiconductor materials (trace element analysis) such as polymer materials, metal oxides, and silicon wafers.

  In the field of sample analysis, an X-ray photoelectron spectrometer (XPS) is used to analyze the structure of a sample surface such as a wafer and the atoms or molecules in the vicinity of the sample surface. In the XPS, a sample is irradiated with X-rays in an ultra-high vacuum, the energy of photoelectrons emitted from the sample is measured with an energy analyzer, and the element and chemical bonding state on the sample surface are measured.

  FIG. 9 is an explanatory diagram of X-ray photoelectron spectroscopy. When the X-ray 42 enters the sample 1 at a predetermined angle, photoelectrons 43 are emitted from the surface of the sample 3. By analyzing this photoelectron 43 with an energy analyzer, it is possible to analyze the structure of the element having a depth of δ near the surface of the sample 3.

  In photoelectron spectrometers, when photoelectrons are measured by making the photoelectron excitation beam incident on the surface of the measurement sample below the critical angle of total reflection determined by the wavelength of the excitation light and the measurement substance, the penetration of the excitation light into the sample The depth becomes very shallow, and the detection efficiency can be increased by several orders of magnitude or more with respect to the elemental composition of the surface as compared with the measurement by a normal photoelectron spectrometer. FIG. 10 is a diagram showing X-ray incidence below the total reflection critical angle. X-rays 42 are incident on the sample 3 at an incident angle α, and photoelectrons 43 are emitted from the sample 3. A photoelectron spectrometer that uses such incident light conditions is called a total reflection photoelectron spectrometer (TRXPS).

In order for the total reflection photoelectron spectrometer to work properly, the surface of the sample is required to be extremely flat.
Further, as an XPS measurement method, an angle-resolved XPS measurement method (ARXPS) is known as a method in which X-rays are obliquely applied to a sample to obtain information in the depth direction. Here, in ARXPS, a sample is irradiated with being tilted with respect to X-rays. According to this method, information in the depth direction of the sample can be obtained. Therefore, information in the depth direction of the sample can be obtained nondestructively.

  As a conventional apparatus of this type, by irradiating a sample to be analyzed with particles composed of 100 or more atoms or molecules in a reduced pressure atmosphere, the efficiency of etching is not lowered, and the binding state of the sample to be analyzed There is known a technique for performing an accurate elemental analysis in the depth direction by cutting a sample to be analyzed without changing the composition (for example, see Patent Document 1).

In addition, a technique is known in which a sample surface can be subjected to ultraprecision polishing at an atomic level (see, for example, Patent Document 2).
In addition, an electrospray ion source that emits various inert gases, ions of oxygen, nitrogen, etc. with high brightness and a focused ion beam device equipped with this are realized. There is known a technique for performing microfabrication, analysis or measurement without giving contamination to a minute region on the surface of the substrate (see, for example, Patent Document 3).

  Further, there is known a sample analysis method that can perform elemental analysis on the surface of the sample electrode and deeper than that by analysis using total reflection photoelectron spectroscopy without etching (see, for example, Patent Document 4). .

When analyzing the surface and the inside of a sample with the above-described apparatus, it is necessary to flatten the sample surface. In this case, a material surface etching method by irradiation with rare gas monoatomic ions such as Ar ions, a plasma etching method using silane gas, hydrogen gas, or the like, or material surface purification by carbon dioxide gas spraying is performed.
JP-A-8-122283 (paragraphs 0015 to 0018, FIG. 1) JP-A-8-120470 (paragraphs 0008 to 0014, FIG. 1) JP-A-7-161322 (paragraphs 0022 to 0027, FIGS. 1 and 4) JP 2000-97889 A (paragraphs 0011 to 0021, FIG. 1)

In the prior art, the etched surface becomes rough (unevenness), the sample is damaged (detachment of the functional group), the stain is generated during etching, and the like.
1. Conventionally, the Ar ion etching method that is generally used can remove surface contaminants, but the surface of the sample is greatly roughened. As a result, it is difficult to measure the spectrum of the decrease in background intensity, which is characteristic of TRXPS measurement. is there.

  2. In angle-resolved XPS (ARXPS) measurement, which is non-destructive and used for depth analysis, there is a problem in that ARXPS measurement cannot be performed with high sensitivity because contaminants covering the sample surface reduce the lower layer photoelectron intensity.

  3. Since sample damage and surface roughness are caused by the Ar ion etching method, there is a problem that the Ar ion etching method cannot be combined with the TRXPS / ARXPS method. In particular, it is difficult to combine with the TRXPS method, and therefore the depth direction analysis at the atomic / molecular level, which is a feature of the TRXPS method, cannot be performed.

  4). In the usual Ar ion irradiation method and chemical etching method, 1) the surface of the material is roughened, 2) the chemical bond is broken, 3) the metal oxide is reduced, and 4) the surface structure is broken. Etc. The reason for each occurrence is as follows.

  Reason 1): Surface roughening occurs due to selective etching, heat generated during collision of irradiated ions with the sample surface, ion implantation, and the like. As a result, there is a reduction in spectral intensity as an effect on XPS measurement.

Reason 2): Since the energy higher than the energy that the bond is formed is irradiated, the bond is broken.
Reason 3): Deoxygenation due to Ar ions (positive ions) occurs (reduction reaction). In the chemical etching method, decomposition products are deposited.

Reason 4): Since the energy of irradiated ions is high (100 V or more), the surface structure is disturbed by the irradiation of the irradiated ions, resulting in structural destruction.
The present invention solves the problems described above. In particular, with the aim of solving the problems of the conventional method (reason 4), suppressing surface roughness, maintaining the bonded state, suppressing reduction of metal oxides, and maintaining the surface structure, which was impossible with the conventional method. To do. In particular, XPS is suitable for chemical bond state analysis and surface quantitative analysis. In order to measure chemical bond state analysis, quantitative analysis, and internal state distribution more accurately, the above problems must be solved.

  Furthermore, TRXPS is surface sensitive and has a detection limit of two orders of magnitude or better compared to conventional methods. However, it is difficult to apply this measurement method to many materials (surface flattening is not possible).

  The present invention provides a technique for solving the problems of these conventional methods by adopting a charged droplet etching method, preparing a sample surface cleaned and flattened sample, and simplifying TRXPS measurement. Further, it is a technology that enables analysis in the depth direction by XPS, TRXPS, and ARXPS, and improves the resolution in the depth direction, which cannot be achieved by the conventional method, to the atomic / molecular level. In particular, the TRXPS method of performing depth direction analysis while repeating etching with charged droplets is a technology that does not exist so far.

  The present invention has been made in view of the above points, and an X-ray photoelectron spectrometer and a total reflection X-ray photoelectron spectrometer capable of performing highly accurate sample analysis by making the sample surface extremely flat. The purpose is to provide.

  (1) The invention described in claim 1 is an etching means for etching a sample surface using a charged droplet etching method, an X-ray irradiation means for irradiating the etched sample surface with X-rays at a predetermined angle, and X And analyzing means for analyzing the depth direction in the vicinity of the surface of the sample by analyzing photoelectrons emitted from the surface of the sample irradiated with the line.

  (2) The invention according to claim 2 is characterized in that the etching means for etching the surface of the sample using the charged droplet etching method, and the X-ray is irradiated to the etched sample surface at an angle equal to or less than the critical angle for total reflection satisfying the total reflection condition. X-ray irradiating means for irradiating, and analyzing means for analyzing the depth direction of elements and chemical bonds near the surface of the sample by analyzing photoelectrons emitted from the surface of the sample irradiated with X-rays It is characterized by that.

(3) The invention according to claim 3 is characterized in that the charged droplet etching method etches the sample surface using a charged droplet cluster ion beam.
(4) The invention according to claim 4 is characterized in that the charged droplet etching method etches the sample surface using a charged droplet cluster ion beam.

  (5) The invention according to claim 5 is an etching means for etching the surface of a sample using a charged droplet etching method, an X-ray irradiation means for irradiating the etched sample surface with X-rays at a predetermined angle, and X And analyzing means for analyzing the depth direction in the vicinity of the surface of the sample by analyzing photoelectrons emitted from the surface of the sample irradiated with the line.

  (1) According to the first aspect of the present invention, the sample surface can be made extremely flat by etching the sample surface using the charged droplet etching method with the etching means. Depth direction analysis can be performed accurately.

  (2) According to the second aspect of the invention, the sample surface can be made extremely flat by etching the sample surface using the charged droplet etching method by the etching means, and this sample surface is irradiated with X-rays. By irradiating the sample surface with X-rays at an angle less than or equal to the total reflection critical angle satisfying the total reflection condition by means, the depth direction analysis in the vicinity of the sample surface can be performed very accurately.

(3) According to the invention described in claim 3, the surface of the sample can be made extremely flat by using a charged droplet cluster ion beam as the charged droplet etching method.
(4) According to the invention described in claim 4, the surface of the sample can be made extremely flat by using a charged droplet cluster ion beam as the charged droplet etching method.

  (5) According to the invention described in claim 5, since the surface of the sample can be made extremely flat by etching the surface of the sample using the charged droplet etching method by the etching means, Depth direction analysis can be performed accurately.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present invention, by using the charged droplet etching method for X-ray photoelectron spectroscopy (XPS) and total reflection XPS method (TRXPS method), the following matters are possible. Here, the charged droplets are, for example, water made into a fine mass, and the fine mass was charged to form cluster ions. More specifically, the cluster ion is a cluster of many atoms or molecules that are combined by van der Worth force to form a cluster, which is ionized to have a positive charge. The present invention is based on the knowledge newly found by the inventor that the sample surface can be etched extremely flat when such a cluster ion beam is irradiated onto the sample surface.

  1) When performing TRXPS measurement, a flat sample surface that satisfies the X-ray total reflection condition is required. In order to produce a flat sample surface, polishing or the like must be performed. However, when this treatment is performed, contaminants accumulate on the sample surface, making measurement difficult. In addition, if a sample surface is irradiated with a rare gas such as Ar ions generally used for removing contaminants at a high speed (> 100 V) and sputter etching is performed, surface irregularities due to Ar ion irradiation, and further chemical Damage to the bonded state occurs.

  If a processing method capable of suppressing such a phenomenon is used, TRXPS measurement can be stably performed. In order to perform TRXPS measurement, surface smoothing at the nano level is necessary. For this reason, sample preparation suitable for measurement is important. The charged droplet etching method can smooth the sample surface at the nano level.

  2) Atomic / molecular etching at the layer-by-layer level (one layer at a molecular level) is possible. TRXPS measurement is surface sensitive (detection limit improved) by two orders of magnitude or more compared to normal XPS measurement. Therefore, surface trace element measurement is possible. However, if contaminants are accumulated on the sample, improvement in detection limit cannot be expected. The charged droplet etching method enables etching at the atomic / molecular level.

  Therefore, the detection limit at the time of TRXPS measurement can be expected to be improved by etching the surface contaminants with Layer-by-Layer. In addition, depth direction analysis in TRXPS measurement, which has been impossible in the past, is enabled (improvement of depth direction resolution). In addition, the angle-resolved XPS measurement (ARXPS), which is an XPS measurement method, is performed by etching the sample surface by the charged droplet etching method (etching surface contaminants at the Layer-by-Layer level), and analyzing the depth direction near the surface. Can be measured with high sensitivity.

3) Formation of surface state without sample damage When measuring the vicinity of the outermost surface with TRXPS / ARXPS, the presence of surface contaminants becomes a problem as described above (reduction of photoelectron intensity occurs). Therefore, it is important to remove the contaminants without damaging the sample surface in order to improve the TRXPS / ARXPS measurement accuracy. The charged droplet etching method does not damage the surface chemical bonding state even if etching is performed (there is no reduction of metal oxides, damage to organic compounds). Therefore, by analyzing and producing a sample from which there is no sample damage and from which surface contaminants are removed, depth direction analysis in the vicinity of the original surface of the material can be measured with high sensitivity.

4) In-situ analysis In a surface analysis apparatus such as XPS, sample processing and processing must be performed in an ultra-high vacuum (contaminants accumulate when exposed to the atmosphere after processing and processing). In order to further smooth and process the charged droplet cluster ion beam, it must be irradiated at a high angle (near 90 °) with respect to the sample surface.

  FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 4 is a vacuum chamber (preliminary exhaust chamber), 3 is a sample disposed in the vacuum chamber 4, and 2 is a sample exchange rod for exchanging / moving the sample 3. A raster mechanism 9 scans cluster ions for cutting the surface of the sample 3. Reference numeral 1B denotes an evacuation system for pulling the inside of the vacuum chamber 4 to a high vacuum, and includes a rotary pump 20a, a turbo molecular pump 20b, and vacuum gauges 20c and 20d. This configuration is the same for the evacuation system 1A in which the charged droplet etching gun 6 is evacuated through the differential evacuation system 7, and is composed of a rotary pump 20a, a turbo molecular pump 20b, and vacuum gauges 20c and 20d. Yes.

  5 is an electrospray unit that generates charged droplets under atmospheric pressure, 11 is an orifice through which charged droplets generated by the electrospray unit 5 pass, and 12 is a cluster size of charged droplets that have passed through the orifice. An ion guide 8 for selecting is an ion focusing lens system. The electrospray unit 5, the orifice 11, the ion guide 12, and the ion focusing lens system form the charged droplet etching gun 6. Reference numeral 10 denotes a surface analysis chamber that performs surface analysis of the sample 3 by irradiating the sample 3 etched in the vacuum chamber 4 with X-rays.

  The sample 3 ultra-flattened in the vacuum chamber 4 is transferred to the surface analysis chamber 10 connected to the vacuum chamber 4 through the gate valve 42 using the sample exchange rod 2. FIG. 2 is a diagram showing an example of the configuration of the analyzer unit of the present invention in the surface analysis chamber. In the figure, 3 is a sample, and the sample 3 can be moved to an arbitrary position by a three-dimensional sample moving mechanism. That is, the sample moving mechanism has movement adjusting knobs for the X axis, the Y axis, the Z axis, and the T axis. Reference numeral 33 denotes a stage shaft for moving the sample stage 34 to an arbitrary position by the sample moving mechanism.

  An X-ray tube 32 emits X-rays. X-rays emitted from the X-ray tube 32 are dispersed by the spectral crystal 30 so that the dispersed X-rays are incident on the sample 3 at a predetermined incident angle. The photoelectrons emitted from the sample 3 are focused by the electrostatic lens 31 and input to an energy analyzer (not shown) to perform a predetermined elemental analysis. The operation of the present invention will be described using the apparatus configured as described above.

  In the electrospray unit 5, water is sent to a metal capillary to which a high voltage of several kV is applied, and this water is electrostatically sprayed to generate charged fine droplets (cluster ions). The generated cluster ions are mass-selected by the ion guide 12 and accelerated. The accelerated cluster ions are focused and impacted toward the sample 3 by the ion focusing lens system 8. The raster mechanism 9 includes, for example, an electrostatic deflector that deflects cluster ions and raster scans cluster ions on the sample, and can adjust the size of the scanning range, the scanning density, the scanning speed, and the like. By installing this system, the etching area can be made uniform due to sample collision of cluster ions.

  When cluster ions collide with an uneven sample, the ions etch the convex portion of the sample surface, and the sample surface has extremely high flatness. And it becomes possible to give the sample surface uniformity. That is, according to the present invention, the ion dose per unit area is selected by selecting the cluster ion size (selecting the cluster molecule size by the ion guide operation) and selecting the size of the etching region. As a result, the etching rate can be adjusted. As a result, the processing depth from the sample surface can be adjusted.

  In FIG. 1, a differential evacuation system 7 is used for the charged droplet etching gun 6 to enable mounting to an ultra-high vacuum system. The reason is that it can be mounted on an XPS or TRXPS apparatus that requires an ultra-high vacuum. In other words, this is because the processed and processed sample can be introduced into the surface analysis chamber 10 without being exposed to the atmosphere. At this time, introduction of the etched sample 3 into the surface analysis chamber 10 is performed as follows.

  The charged droplet etching of the sample 3 is performed to make the sample surface ultra flat, and then the gate valve 42 is opened while the vacuum chamber 4 is maintained in vacuum. The etched sample 3 is held by the sample exchange rod 2. By operating the sample exchange rod 2, the sample 3 is transferred to the sample stage 34 in the surface analysis chamber 10 through the gate valve 42 and placed. After placement, only the sample exchange rod 2 is retracted to the vacuum chamber 4 and the gate valve 42 is closed.

  In the surface analysis chamber 10, photoelectrons are generated from the transported sample by the apparatus having the configuration shown in FIG. 2, the photoelectrons are focused by the electrostatic lens 31, and introduced into the energy analyzer. Performs depth analysis.

  Thus, according to the present invention, the sample surface can be made extremely flat by etching the sample surface by the charged droplet etching method, so that the depth direction analysis in the vicinity of the sample surface can be accurately performed. Yes (XPS).

  In particular, the depth of the vicinity of the surface of the sample is analyzed by irradiating the etched sample surface with X-rays at an angle less than or equal to the total reflection critical angle satisfying the total reflection condition, and analyzing photoelectrons emitted from the sample surface irradiated with X-rays. Direction analysis can be performed (TRXPS).

  FIG. 3 is a diagram showing the flow of measurement according to the present invention. In (a), charged droplet etching is performed, sample processing enabling TRXPS measurement is performed, X-rays are incident on the sample surface, and photoelectrons emitted from the sample 3 are focused to analyze the surface of the sample. To do. After the measurement, the sample 3 is returned to the sample exchange rod 2 shown in FIG. 1 and the sample is set at the sample position. Then, etching is performed from the charged droplet etching gun body 5.

  Thereafter, the etched sample 3 is moved to the surface analysis chamber 10 and measurement is performed again as shown in FIG. As is clear when (b) and (a) are compared, the surface of the sample is shaved each time etching is performed. Here, since the analysis depth of TRXPS is the mean free path of photoelectrons (the distance traveled until the electrons collide), profile measurement can be performed with a depth resolution of 1 to 2 nanometers.

  By applying this operation to ARXPS, it becomes possible to perform profile measurement with improved resolution in the depth direction compared to conventional ARXPS. The charged droplet etching gun 6 is mounted on the upper portion of the vacuum chamber 4 and irradiates cluster ions at an angle of 45 ° or more with respect to the surface of the sample 3. FIG. 4 is a diagram showing how the sample is irradiated with cluster ions. Cluster ions k are incident on the sample 3 at an incident angle θ. In order to suppress surface roughness after ion irradiation and enable surface cleaning and uniform etching, the incident angle θ in FIG. 4 must be set to a high angle. The ion incident angle necessary for the present invention is desirably 60 ° or more.

  FIG. 5 is a diagram showing the observation result by SEM. This figure is a figure which shows the SEM observation result when an InP (111) sample is etched by the method of the present invention. a is before etching, b is when etched by Ar ion irradiation, and c is when etched by the method of the present invention. Surface roughness due to ion irradiation occurs on many material surfaces, but the roughness on the InP surface is particularly significant. For this reason, InP is generally used for confirmation of surface roughness by ion irradiation.

  As shown in FIG. 5, it can be seen that the ArP irradiation of the conventional method causes significant roughness on the InP surface. This is the effect of heat generated during ion irradiation. If such roughening occurs, even if TRXPS is performed, the X-ray total reflection condition cannot be satisfied. In contrast to this result, it can be seen that there is no etching roughness on the InP surface etched using charged droplet cluster ions. FIG. 5 is a diagram showing an example of the main screen in the display screen displayed on the display in the embodiment of the present invention as a halftone photograph.

  This is because when a sample (such as InP) is irradiated with cluster ions, the energy of each ion is low, so that almost no heat is generated during irradiation. For this reason, there is almost no roughness during etching as shown in c. As described above, in the method of the present invention, the surface roughness of the material (surface unevenness) can be remarkably suppressed, and as a result, a sample surface free of contaminants necessary for TRXPS measurement can be obtained.

  FIG. 6 is a diagram showing the results of XPS measurement. The example shown in the figure shows the result of measuring with an XPS (photoelectron spectrometer) after etching a Si wafer (after hydrofluoric acid cleaning and after natural oxide film removal) by the method of the present invention. The vertical axis is intensity, and the horizontal axis is binding energy. f1 is the result immediately after cleaning, and f2 is the spectrum after etching by the method of the present invention.

  As shown in FIG. 6, no spectral difference is observed. In normal Ar ion irradiation, structural destruction of the Si wafer surface occurs, and the surface structure is changed to amorphous. In this case, the spectrum obtained by XPS measurement is broad. However, as shown in FIG. 6, such a change does not occur in the charged droplet etching method. Also, there is no product accumulation as in chemical etching. As a result, even if the surface subjected to charged droplet cluster ion etching is sufficiently etched, surface structure destruction (chemical bond state change) that causes a problem in XPS or TRXPS measurement does not occur.

  The results shown in FIGS. 5 and 6 indicate that sample surface treatment (processing) necessary for XPS measurement such as TRXPS measurement and ARXPS measurement can be performed. By performing TRXPS measurement (or ARXPS measurement) using the sample thus treated, depth direction analysis at the atomic / molecular level becomes possible.

  FIG. 7 shows a concentration distribution (profile) in the depth direction obtained after etching with charged droplet cluster ions and then performing a TRXPS measurement (measured by repeating etching and measurement) and performing a depth direction analysis. The vertical axis represents the elemental composition ratio, and the horizontal axis represents the depth of the sample. In the figure, profiles for the A element and the B element are shown. (A) shows the profile when the etching treatment is not performed according to the present invention, and (b) shows the profile when the charged droplet cluster etching is performed.

  As shown in the figure, the profile resolution D is improved by performing the etching using the charged droplet cluster ion beam. The resolution D at this time is comparable to the mean free path length of photoelectrons. In other words, it becomes possible to perform profile measurement with atomic / molecular resolution. In the case shown in (a), the depth direction resolution D is smaller in the case shown in (b) using the present invention than in the case where the depth direction resolution D is large.

  As described above, the present invention can be applied to a limited sample by performing sample processing (processing) with charged droplet cluster ions that can be etched at the atomic / molecular level without causing damage to the sample surface. It becomes possible to newly open the TRXPS measurement field that could only be measured. Further, by using TRXPS and this processing (processing) technique, it is possible to analyze in the depth direction, which was not possible with the conventional TRXPS method, and to further improve the resolution of the obtained depth direction profile.

  FIG. 8 is a diagram showing the flow of operation of the present embodiment. In the present embodiment, the sample etched by the etching unit 50 is transported to the energy analyzer unit (TRXPS apparatus main body) 60 while maintaining a high vacuum state, and energy analysis is performed. Next, the same sample is returned to the etching part 50 and etched again. The etched material is also transported to the energy analyzer unit 60 for energy analysis. By repeating the above operation, the surface of the sample 3 is shaved, and by applying incident X-rays to the surface, an elemental composition ratio as shown in the figure is obtained. In the case of the present invention, the resolution in the depth direction is comparable to the atomic / molecular level.

  In the above embodiment, the gate valve 42 is disposed between the vacuum chamber 4 and the surface analysis chamber 10, and the sample etched by the etching unit 50 is energized while maintaining a high vacuum state via the gate valve 42. Although the energy analysis is performed by transporting the sample to the analyzer unit (TRXPS apparatus main body) 60, the vacuum chamber 4 and the surface analysis chamber 10 need not be connected by the gate valve 42. In that case, the sample etched by the etching unit 50 may be stored in a sample container that can be held in vacuum, and the operator may transfer the sample container to the surface analysis chamber 10 for analysis.

    It is also possible to install a charged droplet etching gun in the surface analysis chamber 10. FIG. 11 shows an example of such an embodiment. In FIG. 11, the energy analyzer 60 and the charged droplet etching gun 6 are attached to the chamber 10 so as to be inclined so that analysis and etching can be performed on the same part of the sample. A differential pumping mechanism comprising a plurality of throttles 43 for differential pumping and a vacuum pump for differential pumping 44 for vacuum pumping the space between them is provided at the tip of the charged droplet etching gun 6. Thus, a high vacuum in the surface analysis chamber is maintained.

  In the present embodiment, after the sample 3 is etched by the cluster ions from the charged droplet etching gun, the analysis can be performed using the energy analyzer unit 60 without moving the sample.

  As described above, according to the present invention, an X-ray photoelectron spectrometer, a total reflection X-ray photoelectron spectrometer, and an angle-resolved X which can perform a highly accurate sample analysis by making the sample surface extremely flat. A linear photoelectron spectrometer can be provided.

It is a block diagram which shows one embodiment of this invention. It is a figure which shows the structural example of the analyzer part of this invention. It is a figure which shows the flow of the measurement by this invention. It is a figure which shows the mode of irradiation of the cluster ion to a sample. It is a figure which shows the observation result by SEM. It is a figure which shows a XPS measurement result. It is a figure which shows the measurement result at the time of not having ion etching by this invention. It is a figure which shows the flow of operation | movement of this invention. It is explanatory drawing of a X-ray photoelectron spectroscopy. It is a figure which shows X-ray incidence in less than a total reflection critical angle. It is a block diagram which shows another embodiment of this invention.

Explanation of symbols

1A, 1B Vacuum exhaust system 2 Sample exchange rod 3 Sample 4 Vacuum chamber 5 Electrospray unit 6 Charged droplet etching gun 7 Differential exhaust system 8 Ion focusing lens system 9 Raster mechanism 10 Surface analysis chamber 11 Orifice 12 Ion guides 20a, 20b Rotary pump 20c, 20d Vacuum gauge

Claims (5)

Etching means for etching the surface of the sample using a charged droplet etching method;
X-ray irradiation means for irradiating the etched sample surface with X-rays at a predetermined angle;
Analyzing means for analyzing a depth direction in the vicinity of the surface of the sample by analyzing photoelectrons emitted from the surface of the sample irradiated with X-rays;
An X-ray photoelectron spectrometer characterized by comprising Etching means for etching the surface of the sample using a charged droplet etching method;
X-ray irradiation means for irradiating the etched sample surface with X-rays at an angle equal to or smaller than the total reflection critical angle satisfying the total reflection condition
Analyzing means for analyzing a depth direction in the vicinity of the surface of the sample by analyzing photoelectrons emitted from the surface of the sample irradiated with X-rays;
A total reflection X-ray photoelectron spectrometer characterized by comprising   2. The X-ray photoelectron spectrometer according to claim 1, wherein the charged droplet etching method is to etch a sample surface using a charged droplet cluster ion beam.   3. The total reflection X-ray photoelectron spectrometer according to claim 2, wherein the charged droplet etching method is to etch a sample surface using a charged droplet cluster ion beam. Etching means for etching the surface of the sample using a charged droplet etching method;
X-ray irradiation means for irradiating the etched sample surface with X-rays at a predetermined angle;
Analyzing means for analyzing a depth direction in the vicinity of the surface of the sample by analyzing photoelectrons emitted from the surface of the sample irradiated with X-rays;
An angle-resolved X-ray photoelectron spectrometer characterized by comprising: