JP2012032239A - Sample inspection device and sample inspection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sample inspection device and a sample inspection method that never limits samples which can be inspected by combining a plurality of kinds of measuring method.SOLUTION: The sample inspection device includes an incident part 11, a reflected light reception part 12 and an analysis part 13 (ellipsometer part), an X-ray source 21, a fluorescent X-ray detection part 22 and an analysis part 23 (X-ray measurement part), a laser light source 31, a beam splitter 34, and a Raman scattered light detection part 32 and an analysis part 33 (Raman scattered light measurement part). A thickness of a sample can be measured using a suitable technique corresponding to the sample 6. Further, ellipsometry and fluorescent X-ray analysis are combined together to independently measure the thickness of the sample 6 and optical characteristics of a refraction factor etc. When the sample 6 is a multilayer sample, respective layers can be inspected with suitable samples.

Description

  The present invention relates to a sample inspection apparatus and a sample inspection method for measuring characteristics including the thickness of a sample.

  Semiconductor devices such as solar cell devices include devices having a multilayer structure in which a plurality of layers having different compositions are stacked. There is a need to measure the thickness of each layer and other characteristics during or after the manufacturing process of such an element. An apparatus for inspecting a sample by measuring the thickness and other characteristics of the sample includes an ellipsometer. The ellipsometer irradiates the sample with linearly polarized light, measures the change in the polarization state between the incident light and the reflected light on the sample, and measures the thickness and refractive index of the sample based on the change in the polarization state To do. Patent Document 1 discloses a technique for measuring the thickness of a sample using an ellipsometer. As another sample inspection apparatus, there is a fluorescent X-ray analyzer that irradiates a sample with X-rays and analyzes fluorescent X-rays generated from the sample. When the composition of the sample is known, the thickness of the sample can be measured from the intensity of the fluorescent X-ray.

Japanese Patent Laid-Open No. 2005-233828

  When a sample having a multilayer structure includes a transparent layer such as a gate insulating layer, the thickness of the transparent layer can be measured by an ellipsometer. However, when the sample includes a metal layer such as a wiring layer, light cannot enter the inside of the metal layer, and thus the thickness of the metal layer cannot be measured by an ellipsometer. On the other hand, the fluorescent X-ray analyzer can measure the thickness of the metal layer. However, depending on the composition of the sample, there is a sample including a layer whose thickness is difficult to measure with a fluorescent X-ray analyzer. For example, in a sample in which a transparent layer, which is a gate insulating layer composed of silicon dioxide, is formed on a silicon substrate, silicon fluorescent X-rays from the silicon substrate are distinguished from silicon fluorescent X-rays from the transparent layer. It is difficult to measure the thickness of each layer individually. As described above, the appropriate sample inspection apparatus differs depending on the sample, and there is a problem that it is necessary to use the sample inspection apparatus properly depending on the sample. In particular, in order to measure the characteristics of a multilayer sample, it is necessary to use a plurality of sample inspection apparatuses, which is troublesome.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a sample inspection apparatus and a sample inspection that do not limit the samples that can be inspected by combining a plurality of types of measurement methods. It is to provide a method.

  The sample inspection apparatus according to the present invention includes an ellipsometer unit that makes linearly polarized light incident on a sample, receives reflected light from the sample, and measures a change in polarized light between the incident light and reflected light, and X-rays to the sample And an X-ray measurement unit that measures X-rays from the sample, and an analysis unit that performs an analysis for obtaining the thickness of the sample based on the measurement result of the ellipsometer unit or the X-ray measurement unit A sample inspection apparatus.

  In the sample inspection apparatus according to the present invention, the analysis unit calculates a sample thickness based on a measurement result in the X-ray measurement unit, a measurement result in the ellipsometer unit, and a calculation of the sample thickness. And a means for calculating an optical characteristic of the sample based on the result.

  When the sample is a multilayer sample, the sample inspection apparatus according to the present invention includes means for adjusting the position where the linearly polarized light is incident on the ellipsometer so that the linearly polarized light is incident on an arbitrary layer in the multilayer sample. The analysis unit further includes means for calculating the thickness of the arbitrary layer on which the ellipsometer unit is incident with linearly polarized light based on the measurement result in the ellipsometer unit, and the measurement result in the X-ray measurement unit. And a means for calculating a thickness of another layer in the multilayer sample.

  The sample inspection apparatus according to the present invention further includes a Raman scattered light measurement unit that enters monochromatic light into the sample and measures Raman scattered light generated from the sample, and the analysis unit is a measurement result of the Raman scattered light measurement unit. The method further comprises means for calculating the structural characteristics of the sample based on the above.

  The sample inspection method according to the present invention includes an ellipsometer unit that receives linearly polarized light on a flat sample, receives reflected light from the sample, and measures a change in polarized light between the incident light and the reflected light, and the sample Using a sample inspection apparatus comprising an X-ray measurement unit that irradiates X-rays and measures X-rays from the sample, calculates the thickness of the sample based on the measurement result in the X-ray measurement unit, The optical characteristics of the sample are calculated based on the measurement result in the ellipsometer section and the calculation result of the thickness of the sample.

  In the sample inspection method according to the present invention, when the sample is a multilayer sample, the ellipsometer unit measures a change in polarization between incident light and reflected light for any one layer in the multilayer sample, Measure X-rays from the multilayer sample in the X-ray measurement unit, calculate the thickness of the one layer based on the measurement results in the ellipsometer unit, and based on the measurement results in the X-ray measurement unit, The thickness of the other layer in the multilayer sample is calculated.

  In the present invention, the sample inspection apparatus includes an ellipsometer unit and an X-ray measurement unit, and measures the thickness of the sample based on the measurement result in the ellipsometer unit or the X-ray measurement unit. Therefore, for samples that can be used for analysis using X-rays such as fluorescent X-ray analysis, the thickness of the sample is measured using X-rays, and for samples that are difficult to use for analysis using X-rays, ellipsometry is used. The thickness of the sample can be measured.

  In the present invention, the sample inspection apparatus measures the thickness of the sample by analysis using X-rays, and measures optical characteristics such as the refractive index of the sample based on the measurement result of the ellipsometer unit and the measured thickness of the sample. To do. Therefore, unlike a single ellipsometer, each of the optical properties and thickness of the sample can be measured independently.

  In the present invention, the sample inspection apparatus can measure the thickness of an arbitrary layer in the multilayer sample by ellipsometry, and can measure the thickness of the other layer by analysis using X-rays. The thickness of each layer can be measured simultaneously.

  In the present invention, the sample inspection apparatus further includes a Raman scattered light measurement unit, and measures structural characteristics such as crystallinity of the sample by Raman scattered light analysis separately from analysis using ellipsometry and X-rays. be able to.

  In the present invention, the thickness of the sample can be measured using an appropriate method according to the sample. Since there is no need to use different sample inspection apparatuses depending on the sample, the present invention has excellent effects such as simple labor for inspecting the sample.

1 is a schematic diagram showing a configuration of a sample inspection apparatus according to Embodiment 1. FIG. It is typical sectional drawing which shows the example of a sample. 6 is a schematic diagram illustrating a configuration of a sample inspection apparatus according to Embodiment 2. FIG.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
(Embodiment 1)
FIG. 1 is a schematic diagram showing the configuration of the sample inspection apparatus according to the first embodiment. The sample inspection apparatus includes a sample stage 51 on which the sample 6 is placed, an incident unit 11 that makes linearly polarized light incident on the sample 6 on the sample stage 51, and a reflected light receiving unit that receives reflected light reflected by the sample 6. Part 12. In FIG. 1, incident light and reflected light are indicated by broken-line arrows. The incident unit 11 is an optical system including a white light source such as a xenon lamp, a slit, and a polarizer that converts white light into linearly polarized light. The reflected light receiving unit 12 includes a phase modulator that modulates the phase of the reflected light, an analyzer, a spectrometer that splits the light that has passed through the analyzer, and a photodetector that detects the dispersed light. This is a configured optical system. The reflected light receiving unit 12 is connected to an analysis unit 13 that analyzes the light reception result of the reflected light from the reflected light receiving unit 12.

  The reflected light receiving unit 12 outputs the detected intensity of light corresponding to the phase modulation to the analyzing unit 13 for each of the dispersed wavelengths. The analysis unit 13 determines the phase difference Δ between the s-polarized light that is the polarization component perpendicular to the incident surface of the sample 6 and the p-polarization that is the parallel polarization component, and the s-polarization from the detected intensity of light according to the phase modulation The reflection amplitude ratio angle Ψ with p-polarized light is measured for each wavelength. Δ and ψ are measured values in ellipsometry. In this way, the analysis unit 13 acquires the change in wavelength of Δ and Ψ of the sample 6. The incident part 11, the reflected light receiving part 12, and the analysis part 13 correspond to the ellipsometer part in the present invention, and inspect the sample 6 by ellipsometry.

  The sample inspection apparatus further detects an X-ray source 21, an optical system (not shown) that irradiates the sample 6 with X-rays generated by the X-ray source 21, and fluorescent X-rays generated on the sample 6 by X-ray irradiation. And a fluorescent X-ray detection unit 22. At least the X-ray source 21, the sample stage 51, and the fluorescent X-ray detector 22 are housed in a housing (not shown) that shields X-rays. In FIG. 1, X-rays and fluorescent X-rays applied to the sample 6 are indicated by solid arrows. The X-ray source 21 is an X-ray tube that generates X-rays by causing accelerated electrons to collide with a metal target. The fluorescent X-ray detection unit 22 is disposed at a position where the fluorescent X-ray generated from the sample 6 can be detected. The fluorescent X-ray detection unit 22 includes a detection element such as a proportional counter or a semiconductor detector. Connected to the fluorescent X-ray detection unit 22 is an analysis unit 23 that analyzes the detection result of the fluorescent X-rays.

  The fluorescent X-ray detection unit 22 outputs an electrical signal proportional to the energy of the fluorescent X-rays incident on the detection element to the analysis unit 23. The analysis unit 23 sorts the electric signal from the fluorescent X-ray detection unit 22 according to the signal intensity, and counts the electric signal of each signal intensity, whereby the relationship between the wavelength of the fluorescent X-ray and the count number, that is, the fluorescence. An X-ray spectrum is acquired. The X-ray source 21, the fluorescent X-ray detection unit 22, and the analysis unit 23 correspond to the X-ray measurement unit in the present invention, and inspect the sample 6 by fluorescent X-ray analysis. FIG. 1 shows a form in which the optical path of light used in ellipsometry and the optical path of X-ray used in fluorescent X-ray analysis are on the same plane. The form which exists on the plane which an optical path cross | intersects may be sufficient.

  The sample inspection apparatus further separates the laser light source 31, an optical system (not shown) that irradiates the sample 6 with the laser light from the laser light source 31, and the Raman scattered light generated from the sample 6 by the laser light irradiation. A beam splitter 34 and a Raman scattered light detector 32 are provided. By irradiating the sample 6 with laser light, Raman scattered light excited by the laser light is generated from the sample 6. The Raman scattered light is separated from the laser light by the beam splitter 34 and enters the Raman scattered light detection unit 32. In FIG. 1, laser light and Raman scattered light irradiated on the sample 6 are indicated by two-dot chain arrows. The Raman scattered light detection unit 32 is an optical system that includes an optical filter, a spectroscope that splits Raman scattered light, and a photodetector that detects the split light. The Raman scattered light detection unit 32 is connected to an analysis unit 33 that analyzes the detection result of the Raman scattered light.

  The Raman scattered light detection unit 32 outputs the detected intensity of the Raman scattered light to the analysis unit 33 for each of the dispersed wavelengths. The analysis unit 33 acquires the relationship between the wavelength of the Raman scattered light and the detection intensity, that is, the spectrum of the Raman scattered light. The laser light source 31, the beam splitter 34, the Raman scattered light detection unit 32, and the analysis unit 33 correspond to the Raman scattered light measurement unit in the present invention, and inspect the sample 6 by the Raman scattered light analysis.

  The sample stage 51 is connected to a drive unit 52 that moves the sample stage 51 up and down using a motor or the like. When the driving unit 52 moves the sample stage 51 up and down, the sample 6 is moved up and down, and the focal position in the linearly polarized sample 6 on which the incident unit 11 is incident and the sample 6 of the laser beam irradiated by the laser light source 31 are displayed. It is possible to adjust the focal position within. When the sample 6 has a multilayer structure, the drive unit 52 can adjust the focal position so that linearly polarized light or laser light is incident on the measurement target layer in the sample 6. The drive unit 52 can change the measurement target layer for ellipsometry and Raman scattering light analysis by moving the focal position in the sample 6.

  The analysis units 13, 23 and 33 and the drive unit 52 are connected to the analysis unit 4. The analysis unit 4 includes an interface for inputting / outputting data, an input unit for inputting instructions from the user, a calculation unit for executing various calculations, a memory for storing information and programs necessary for the calculation, and an analysis result. An output unit such as a printer for output is included. The analysis unit 13 outputs Δ and Ψ wavelength changes of the sample 6 to the analysis unit 4, the analysis unit 23 outputs the fluorescent X-ray spectrum to the analysis unit 4, and the analysis unit 33 analyzes the spectrum of the Raman scattered light. Output to unit 4. The analysis unit 4 has a function of controlling the operation of the drive unit 52.

  FIG. 2 is a schematic cross-sectional view showing an example of the sample 6. A sample 6 shown in FIG. 2 is a solar cell element having a multilayer structure. In the sample 6, a metal metal layer 64, a p-type layer 63 made of a p-type semiconductor, an n-type layer 62 made of an n-type semiconductor, and a transparent layer 61 are laminated. The metal layer 64 is a back electrode made of a metal such as Cu or Mo. The transparent layer 61 is a transparent electrode made of ZnO or ITO. The p-type layer 63 and the n-type layer 62 are made of a semiconductor such as polycrystalline silicon, amorphous silicon, or a compound semiconductor, and are light absorption layers of the solar cell element. Although simplified in FIG. 2, an actual solar cell element includes more layers. In the present invention, it is also possible to inspect a sample having a single layer structure.

  Consider measuring the thickness of the transparent layer 61 in the sample 6 shown in FIG. When the composition of the transparent layer 61 is different from that of the n-type layer 62, the p-type layer 63, and the metal layer 64, the thickness can be measured using fluorescent X-ray analysis. At this time, the X-ray source 21 irradiates the sample 6 with X-rays, the fluorescent X-ray detection unit 22 detects fluorescent X-rays from the sample 6, and the analysis unit 23 acquires a fluorescent X-ray spectrum. The analysis unit 4 extracts the fluorescent X-ray intensity of the element not included in the other layer among the elements included in the transparent layer 61 from the fluorescent X-ray spectrum, and the extracted fluorescent X-ray intensity and previously determined A process for calculating the thickness of the transparent layer 61 is performed based on the concentration of the element in the transparent layer 61.

  In addition, when the element in the transparent layer 61 is included in any of the n-type layer 62, the p-type layer 63, and the metal layer 64, it is difficult to measure the thickness using fluorescent X-ray analysis. Thickness measurement using ellipsometry is possible. The drive unit 52 moves the sample stage 51 up and down to position the focal point of linearly polarized light on which the incident unit 11 is incident on the transparent layer 61. The incident part 11 makes linearly polarized light incident on the transparent layer 61 of the sample 6, the reflected light from the transparent layer 61 is received by the reflected light receiving part 12, and the analyzing part 13 changes the wavelength changes of Δ and Ψ of the transparent layer 61. get. The analysis unit 4 compares the assumed wavelength change of Δ and Ψ derived from the assumed optical characteristics such as refractive index and the thickness of the transparent layer 61 and the thickness with the actually obtained wavelength change of Δ and Ψ, and compares the optical characteristics and thickness. The process of obtaining the optical characteristics and thickness of the transparent layer 61 is performed by repeating the comparison while changing.

  As described above, the sample inspection apparatus according to the first embodiment measures the thickness of one layer in the sample 6 by the fluorescent X-ray analysis when the fluorescent X-ray analysis can be used, and the fluorescent X-ray analysis can be used. When it is difficult, the thickness of the layer can be measured by ellipsometry. As described above, the sample inspection apparatus according to the first embodiment can measure the thickness of each layer by using an appropriate method according to the sample 6 regardless of the sample 6. Since there is no need to use a different sample inspection apparatus depending on the sample 6, the labor involved in inspecting the sample 6 becomes simple. In the case of the sample 6 whose composition is unknown, it is also possible to perform composition analysis by fluorescent X-ray analysis.

  Next, consider measuring the optical characteristics of the transparent layer 61. When the composition of the transparent layer 61 is different from that of the n-type layer 62, the p-type layer 63, and the metal layer 64, it is possible to use both X-ray fluorescence analysis and ellipsometry. First, the X-ray source 21 irradiates the sample 6 with X-rays, and the analysis unit 4 calculates the thickness of the transparent layer 61 by analyzing the spectrum of fluorescent X-rays, and stores the calculated thickness of the transparent layer 61. . Next, the incident part 11 makes linearly polarized light incident on the transparent layer 61 of the sample 6. The analysis unit 4 fixes the thickness value of the transparent layer 61 to a value measured by fluorescent X-ray analysis, and changes Δ and Ψ derived from the optical characteristics and thickness of the transparent layer 61 while changing the optical characteristics of the transparent layer 61. The process of obtaining the optical characteristics of the transparent layer 61 is performed by repeating the comparison between the change in wavelength and the actually obtained change in wavelength of Δ and Ψ.

  As described above, in the present invention, the thickness of one layer in the sample 6 can be measured by fluorescent X-ray analysis, and the optical characteristics such as the refractive index of the same layer can be measured by ellipsometry. A single ellipsometer cannot measure the optical properties and thickness of the layers independently. On the other hand, in the present invention, each of the optical characteristics and thickness of the layer can be measured independently. Therefore, according to the present invention, the optical characteristics such as the refractive index and the thickness of each layer included in the sample 6 can be measured with higher accuracy.

  In the sample inspection apparatus according to the first embodiment, the analysis unit 4 can control the operations of the incident unit 11 and the X-ray source 21 so that the incident unit 11 and the X-ray source 21 can be operated simultaneously. Visible light incident on the sample 6 by the incident part 11 and X-rays irradiated by the X-ray source 21 on the sample 6 have different wavelength regions, and thus do not interfere with each other. The reflected light received by the reflected light receiving unit 12 and the fluorescent X-ray detected by the fluorescent X-ray detection unit 22 have different wavelength regions, and therefore can be detected simultaneously without interfering with each other. That is, the sample inspection apparatus according to Embodiment 1 can simultaneously acquire the wavelength change of Δ and Ψ of the sample 6 and the fluorescent X-ray spectrum of the sample 6. The analysis unit 4 performs processing for independently obtaining the optical characteristics and thickness of the sample 6 based on the wavelength changes of Δ and Ψ of the sample 6 and the fluorescent X-ray spectrum obtained at the same time. Therefore, the sample inspection apparatus according to Embodiment 1 can measure the optical characteristics such as the refractive index and the thickness of each layer included in the sample 6 in a short time.

  Next, consider measuring the thickness of the transparent layer 61 and the metal layer 64 in the sample 6. Since it is difficult to measure the thickness of the metal layer 64 by ellipsometry, the thickness of the metal layer 64 is measured by fluorescent X-ray analysis, and the thickness of the transparent layer 61 is measured by ellipsometry. The driving unit 52 positions the focal point of the linearly polarized light incident on the incident unit 11 on the transparent layer 61, the incident unit 11 enters the linearly polarized light on the transparent layer 61 of the sample 6, and the reflected light receiving unit 12 is the transparent layer 61. The analysis unit 13 acquires the change in wavelength of Δ and Ψ of the transparent layer 61. The analysis unit 4 performs processing for obtaining the thickness of the transparent layer 61 based on the wavelength change of Δ and Ψ. The X-ray source 21 irradiates the sample 6 with X-rays, the fluorescent X-ray detection unit 22 detects fluorescent X-rays from the sample 6, and the analysis unit 23 acquires a fluorescent X-ray spectrum. The analysis unit 4 extracts, from the fluorescent X-ray spectrum, the fluorescent X-ray intensity of elements included in the metal layer 64 that are not included in other layers, and based on the extracted fluorescent X-ray intensity, A process of calculating the thickness of the metal layer 64 is performed.

  As described above, the sample inspection apparatus according to the first embodiment measures the thickness of a plurality of layers included in the sample 6 by using the fluorescent X-ray analysis for the layers that can be used for the fluorescent X-ray analysis. For layers for which metrics can be used, the thickness of the layer can be measured by ellipsometry. As described above, the sample inspection apparatus according to Embodiment 1 can measure the thickness of each of the plurality of layers included in the sample 6 having the multilayer structure by using an appropriate technique according to the layer. There is no need to use a different sample inspection apparatus depending on the layer to be measured, and the thickness of a plurality of layers can be measured with the same sample inspection apparatus, so that labor for inspecting the sample is simplified.

  In the sample inspection apparatus according to the first embodiment, the incident unit 11 and the X-ray source 21 are simultaneously operated to simultaneously acquire the Δ and Ψ wavelength changes of the transparent layer 61 and the fluorescent X-ray spectrum of the metal layer 64. can do. The analysis unit 4 performs processing for independently obtaining the thickness of the transparent layer 61 and the thickness of the metal layer 64 based on the simultaneously obtained Δ and Ψ wavelength changes of the transparent layer 61 and the fluorescent X-ray spectrum of the metal layer 64. . Therefore, the sample inspection apparatus according to Embodiment 1 can measure the thickness of each of a plurality of layers included in the sample 6 having a multilayer structure in a short time.

  Furthermore, the sample inspection apparatus according to Embodiment 1 can perform Raman scattering light analysis of the sample 6. The layer to be subjected to the Raman scattered light analysis measurement is defined as n being multilayer 62. The drive unit 52 moves the sample stage 51 up and down to position the focal point of the laser light from the laser light source 31 on the n-type layer 62. The laser light source 31 irradiates the n-type layer 62 with laser light, the Raman scattered light detector 32 detects the Raman scattered light from the n-type layer 62, and the analyzer 33 analyzes the spectrum of the Raman scattered light from the n-type layer 62. To get. The analysis unit 4 performs a process of calculating structural characteristics such as crystallinity of the n-type layer 62 from the spectrum of Raman scattered light. Thereby, for example, the crystallinity of polycrystalline silicon or amorphous silicon contained in the n-type layer 62 can be measured. In addition to the crystallinity, other structural characteristics such as stress in the n-type layer 62 can be measured by Raman scattering light analysis. Further, the Raman scattered light analysis can be performed on other layers other than the n-type layer 62.

  As described above, the sample inspection apparatus according to Embodiment 1 can measure structural characteristics such as crystallinity for each layer in the sample 6 by Raman scattering light analysis, separately from ellipsometry and fluorescent X-ray analysis. it can. Since it is not necessary to use another sample inspection apparatus for performing the Raman scattered light analysis, the labor for inspecting the sample becomes simple. In addition, since the laser light and the Raman scattered light irradiated to the sample 6 by the laser light source 31 in order to perform the Raman scattered light analysis have different wavelength regions from the X-rays, the Raman scattered light analysis and the fluorescent X-ray analysis can be performed simultaneously. . For example, the sample inspection apparatus acquires the Raman scattered light spectrum and the fluorescent X-ray spectrum of the n-type layer 62 at the same time, and the analysis unit 4 can perform processing for obtaining the structural characteristics and thickness of the n-type layer 62. . Therefore, the sample inspection apparatus according to Embodiment 1 can measure the structural characteristics such as crystallinity and the thickness of the sample 6 in a short time.

(Embodiment 2)
FIG. 3 is a schematic diagram showing the configuration of the sample inspection apparatus according to the second embodiment. The sample inspection apparatus detects an X-ray source 71 and reflected X-rays reflected by the sample 6 from the X-ray source 71 instead of the X-ray source 21, the fluorescent X-ray detection unit 22, and the analysis unit 23. The apparatus includes a reflected X-ray detection unit 72 and an analysis unit 73 that analyzes the detection result of the reflected X-ray. The sample inspection apparatus further includes an optical system (not shown) that irradiates the sample 6 with X-rays from the X-ray source 71 and changes the incident angle of the X-rays with respect to the sample 6 during X-ray irradiation. The X-ray source 71 is an X-ray tube, and the reflected X-ray detector 72 is arranged at a position where the reflected X-ray from the sample 6 can be detected. The reflected X-ray detection unit 72 includes a detection element that counts the X-ray intensity, and outputs an electrical signal indicating the detected intensity of the reflected X-ray to the analysis unit 73. The X-ray source 71, the reflected X-ray detection unit 72, and the analysis unit 73 correspond to the X-ray measurement unit in the present invention.

  The analysis unit 73 classifies the electrical signals from the reflected X-ray detection unit 72 according to the incident angle of the X-ray, and relates to the relationship between the incident angle of the X-ray and the intensity of the reflected X-ray with respect to the sample 6, that is, the incident angle of the X-ray The intensity change of the reflected X-ray is acquired. The analysis unit 73 is connected to the analysis unit 4 and outputs a change in the intensity of the reflected X-ray with respect to the incident angle of the X-rays to the analysis unit 4. The analysis unit 4 executes a simulation of the intensity change of the reflected X-ray with respect to the incident angle of the X-ray, compares the measurement result of the intensity change of the reflected X-ray input from the analysis unit 73 with the simulation result, and sets the simulation parameter. Perform optimization processing. The analysis unit 4 calculates the film thickness, density, and roughness of each layer of the sample 6 by optimizing the simulation parameters. In this way, the X-ray source 71, the reflected X-ray detector 72, the analyzer 73, and the analyzer 4 analyze the sample 6 by XRR (X-ray reflectivity method). Other configurations of the sample inspection apparatus are the same as those of the first embodiment, and the corresponding parts are denoted by the same reference numerals and the description thereof is omitted.

  Similarly to the first embodiment, the sample inspection apparatus according to the second embodiment measures the thickness of one layer in the sample 6 by XRR when XRR can be used, and the ellipso when XRR is difficult to use. The thickness of the layer can be measured by measurement. As described above, the sample inspection apparatus according to the second embodiment can measure the thickness of each layer by using an appropriate method according to the sample 6, and it is not necessary to use a different sample inspection apparatus depending on the sample 6. Similarly to the first embodiment, the sample inspection apparatus according to the second embodiment can measure the thickness of each of a plurality of layers included in the multilayer structure sample 6 by using an appropriate method according to the layers. Therefore, it is not necessary to use different sample inspection apparatuses depending on the layer to be measured. Therefore, the labor for inspecting the sample 6 is simplified. In addition, the sample inspection apparatus according to Embodiment 2 can measure the density and roughness of each layer included in the sample 6 by XRR.

  In addition, the sample inspection apparatus according to the second embodiment measures the thickness of one layer in the sample 6 by XRR and measures optical characteristics such as the refractive index of the same layer by ellipsometry, as in the first embodiment. be able to. Therefore, also in Embodiment 2, it is possible to measure the optical characteristics such as the refractive index and the thickness of each layer included in the sample 6 with higher accuracy. Similarly to the first embodiment, the sample inspection apparatus according to the second embodiment performs XRR processing and ellipsometry processing in parallel, so that each of a plurality of layers included in the multilayered sample 6 is performed. Can be measured in a short time.

  Furthermore, the sample inspection apparatus according to the second embodiment measures structural characteristics such as crystallinity for each layer in the sample 6 by Raman scattered light analysis, separately from XRR and ellipsometry, as in the first embodiment. be able to. The Raman scattered light analysis and the XRR can be performed in parallel, and the sample inspection apparatus according to the second embodiment shortens the structural characteristics such as crystallinity and the thickness of the sample 6 as in the first embodiment. It becomes possible to measure in time.

  In the second embodiment, the XRR is performed without performing the fluorescent X-ray analysis. However, the sample inspection apparatus according to the present invention can perform the fluorescent X-ray analysis in addition to the XRR. There may be. That is, the sample inspection apparatus may further include an X-ray source 21, a fluorescent X-ray detection unit 22, and an analysis unit 23 in addition to the configuration shown in FIG. Further, the sample inspection apparatus may have a form in which an X-ray X-ray source irradiated to the sample 6 for XRR and an X-ray X-ray source irradiated to the sample 6 for fluorescent X-ray analysis are shared. Good.

DESCRIPTION OF SYMBOLS 11 Incident part 12 Reflected light light-receiving part 13 Analysis part 21 X-ray source 22 Fluorescence X-ray detection part 23 Analysis part 31 Laser light source 32 Raman scattered light detection part 33 Analysis part 34 Beam splitter 4 Analysis part 51 Sample stand 6 Sample 71 X-ray Source 72 Reflected X-ray detection unit 73 Analysis unit

Claims (6)

An ellipsometer unit that receives linearly polarized light on the sample, receives reflected light from the sample, and measures a change in polarized light between the incident light and the reflected light;
An X-ray measurement unit that irradiates the sample with X-rays and measures the X-rays from the sample;
A sample inspection apparatus comprising: an analysis unit that performs an analysis for obtaining a thickness of the sample based on a measurement result in the ellipsometer unit or the X-ray measurement unit. The analysis unit
Means for calculating the thickness of the sample based on the measurement result in the X-ray measurement unit;
The sample inspection apparatus according to claim 1, further comprising: a unit that calculates an optical characteristic of the sample based on a measurement result of the ellipsometer unit and a calculation result of the thickness of the sample. When the sample is a multilayer sample, the ellipsometer unit further includes means for adjusting the position where the linearly polarized light is incident so that the linearly polarized light is incident on an arbitrary layer in the multilayer sample,
The analysis unit
Based on the measurement result in the ellipsometer unit, the ellipsometer unit calculates the thickness of the arbitrary layer on which the linearly polarized light is incident;
The sample inspection apparatus according to claim 1, further comprising: means for calculating a thickness of another layer in the multilayer sample based on a measurement result in the X-ray measurement unit. A monochromatic light is incident on the sample, and a Raman scattered light measurement unit that measures the Raman scattered light generated from the sample is further provided.
The analysis unit
The sample inspection apparatus according to any one of claims 1 to 3, further comprising means for calculating a structural characteristic of the sample based on a measurement result of the Raman scattered light measurement unit. An ellipsometer that enters linearly polarized light into a flat sample, receives reflected light from the sample, and measures the change in polarization between the incident light and reflected light;
Using a sample inspection apparatus that includes an X-ray measurement unit that irradiates a sample with X-rays and measures X-rays from the sample,
Based on the measurement result in the X-ray measurement unit, the thickness of the sample is calculated,
A sample inspection method, comprising: calculating an optical characteristic of a sample based on a measurement result in the ellipsometer unit and a calculation result of a sample thickness. When the sample is a multilayer sample, the ellipsometer unit measures the change in polarization between incident light and reflected light for any one layer in the multilayer sample,
The X-ray measurement unit measures X-rays from the multilayer sample,
Based on the measurement result in the ellipsometer, calculate the thickness of the one layer,
The sample inspection method according to claim 5, wherein the thickness of another layer in the multilayer sample is calculated based on a measurement result in the X-ray measurement unit.

Images