JP2013143364A - Charged particle beam device for observing internal construction of sample - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that when an internal construction of a sample is analyzed, there is a case where a dedicated device is required, there is a fear of physical damage, such as destruction, loss, or deformation, of the sample due to cross-section segmentation, or there is a fear that evaluation of an original shape of the sample may be impossible because of chemical/physical alteration of the sample due to exposure to the atmosphere or the like.SOLUTION: A charged particle beam device which creates an image of a sample by irradiating the sample with a charge particle beam and using a secondary signal generated through the irradiation, includes: an uneven shape analysis part for analyzing an uneven shape of a surface of the sample from the image of the sample; a composition analysis part for evaluating a thickness of a same-composition portion by analyzing a composition in a thickness direction of the sample in an arbitrary area of the sample; and an internal construction structuring part for structuring an internal construction of the sample on the basis of the thickness of the same-composition portion and the uneven shape of the surface of the sample. With this configuration, it is possible to two-dimensionally or three-dimensionally structure the internal construction of the sample in a nondestructive manner.

Description

  The present invention relates to a charged particle beam apparatus such as a scanning electron microscope and a pattern measurement / inspection apparatus using the same. In particular, it relates to a technique for observing the internal structure of a sample.

  A method of measuring and observing a three-dimensional structure of a sample shape using a charged particle beam apparatus such as a scanning electron microscope is known. A scanning electron microscope irradiates a sample surface with an electron beam and acquires an image based on secondary particle signals such as secondary electrons and reflected electrons obtained from the irradiated region. These secondary particles mainly have information from the vicinity of the sample surface. In general, observation from above the sample using secondary particles or the like can only provide information about the surface of the sample.

  Methods for analyzing the internal structure of the sample include CT method, ion milling method, FIB method, mechanical polishing method, cutting method, etc., but if a dedicated device is required or if the sample is cut, It may be accompanied by disappearance. In particular, in the case of analyzing a foreign substance or the like contained in a sample, there is a risk of causing a change in form such as deformation or dropping of the foreign substance in the physical cross-section preparation such as the above-described cutting method. In addition, mechanical polishing and cutting methods are easy to apply to analysis in a wide area, but are difficult to apply to internal structure analysis in a local area.

  On the other hand, as described in Patent Document 1, there is known a technique for observing the structure inside the sample by using the change in the penetration depth of the primary electron beam into the sample by the acceleration voltage.

JP-A-11-250850

  However, since the invention described in Patent Document 1 observes a sample to be observed with a scanning transmission image, the sample is sliced by an ion milling method, FIB method, mechanical polishing method, cutting method or the like until the sample can be observed. Because it is necessary, non-destructive internal structure analysis is difficult.

  An object of the present invention is to analyze the internal structure of a sample without damaging the sample and regardless of the shape of the sample or the substrate by performing observation or analysis from the surface of the sample.

  A charged particle beam apparatus that irradiates a sample with a charged particle beam and generates an image of the sample from a secondary signal generated by the irradiation, and analyzes the uneven shape of the surface of the sample from the sample image A composition analysis unit that analyzes the composition in the thickness direction of the sample in an arbitrary region of the sample and evaluates the thickness of the portion having the same composition, and the thickness of the portion having the same composition and the uneven shape of the sample surface And an internal structure constructing section for constructing the internal structure of the sample based on the above.

  Since observation / analysis is performed from the sample surface and data acquisition is performed, the internal structure of the sample (film thickness, foreign matter shape, etc.) can be grasped without breaking the sample.

It is the schematic of the whole structure of a charged particle beam apparatus. (A) Explanatory drawing of electron beam penetration depth, (b) It is schematic explanatory drawing of the film thickness measurement in multiple points. It is a figure explaining the outline of the uneven | corrugated shape measurement of the sample surface. It is the flowchart which showed an example of the sample internal structure analysis. It is an example of internal structure analysis of the sample which included the foreign material.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, although the Example of a scanning electron microscope is described below, it is applicable also to charged particle beam apparatuses, such as a pattern measurement apparatus, a sample observation apparatus, and a defect inspection apparatus which applied the scanning electron microscope. The charged particle beam device here refers to a device having means for irradiating a sample with a charged particle beam and generating an image from secondary signals such as secondary electrons and reflected electrons generated by irradiation.

  FIG. 1 is a diagram showing an outline of the entire configuration of the scanning electron microscope of the present embodiment, and is a schematic diagram showing a cross section of the scanning electron microscope.

  Heat or voltage is applied to the electron gun 101, the electron beam 102 is emitted, converged by the converging lens 103, and scanned by the deflector 104. One or more converging lenses 103 and deflectors 104 converge the electron beam 102. The electron beam 102 is further converged as a minute spot by the objective lens 105 and irradiated onto the sample 106. Image acquisition or composition analysis is performed by secondary signals 107 (secondary electrons, reflected electrons, absorption current, characteristic X-rays, etc.) generated from the sample 106 by irradiation of the electron beam 102.

  In the image acquisition, the secondary signal detected by the secondary electron detector 110 or the backscattered electron detector 108 is associated with the pixel at the scanning position on the sample and displayed on the display unit 111 or an image is generated as digital data.

  An X-ray detector 109 is used for the composition analysis. When the sample is irradiated with the electron beam 102, a secondary signal 107 having sample composition information such as characteristic X-rays is generated from the sample. By detecting this and analyzing the spectrum, the composition of the region irradiated with the electron beam 102 can be analyzed.

  The acquired image and the analyzed composition of the sample are displayed on the display unit 111. The display unit may be provided in the scanning electron microscope main body, or may be a display unit such as a remote computer connected by a network. The control PC 112 is used when building the internal structure from the acquired film thickness information, etc., but the control PC 112 may also be provided in the scanning electron microscope main body, or may be a remote computer connected via a network. Also good.

  In addition, the objective lens 105 is an in-lens method in which a sample is inserted into the objective lens to realize high-resolution observation, an out-lens method that can accommodate a large sample by arranging the sample below the objective lens, or a virtual image below the objective lens. Various systems such as a snorkel lens system (semi-in-lens system) that achieves both high resolution and large sample observation by using a lens are used. X-ray analysis can be performed according to the energy dispersive type that performs identification according to the energy of characteristic X-rays detected using a semiconductor detector and pulse height analyzer, or according to the wavelength of characteristic X-rays detected using a spectroscopic crystal. Various methods such as a wavelength dispersion type are used.

  Further, the charged particle beam apparatus according to the present embodiment may be connected to other external observation apparatuses, inspection apparatuses, and the like via a network, and input / output position information of analysis target locations.

  2A and 2B are explanatory diagrams of film thickness measurement. FIG. 2A is an explanatory diagram of an electron beam penetration depth, and FIG. 2B is a schematic explanatory diagram of film thickness measurement at a plurality of points.

  The film 202 formed on the substrate 201 is irradiated with an electron beam 203. The film on the substrate is formed of one layer or a plurality of layers having different compositions. As shown in FIG. 2A, when the electron beam 203 is irradiated, characteristic X-rays 205 are generated from a region irradiated with the composition analysis electron beam 203. The region and depth of the electron beam 203 that enter the sample differ depending on the energy determined by the acceleration voltage, the element constituting the sample, the density, the crystal state, and the like. Hereinafter, an area where X-rays are generated when the electron beam 203 enters is referred to as an X-ray generation area 204. The electron beam 203 is calculated from information such as the element constituting the sample, density, and film thickness, and an acceleration voltage that reaches the substrate 201 through the film 202 is automatically selected. Conditions for changing the X-ray generation region include an acceleration voltage, an element constituting the sample, a density, and a crystal state. The region where the characteristic X-ray 205 is generated, which is calculated from the qualitative analysis of the characteristic X-ray 205 detected by the X-ray detector 206 and which includes the electron beam irradiation conditions such as the acceleration voltage. Calculation is performed from the quantitative analysis result obtained by calculating the characteristic X-ray 205 detected by the detector 206 and the density information of the elements constituting the sample, and the film thickness information 207 of the film 202 is obtained.

  When measuring the unevenness of the film surface or when obtaining the film thickness distribution, the film thickness information 210 at a plurality of points is acquired. In particular, when the position of the unevenness is known, the electron beam 209 is irradiated to a plurality of points in a line shape or a grid shape so as to cross or surround the recess 208. The irradiation point of the electron beam 209 needs to select at least one point inside and outside the recess. Although the concave portion has been described, the same applies to the convex portion. As will be described below, when a foreign substance is included in the sample, the concave portion or the convex portion can be rephrased as a region on the sample that is vertically above the foreign matter.

  As described above, the sample is described as being a film laminated on the substrate. However, the sample is not necessarily a film and may be a structure formed in the height direction of the sample. Examples of such deformation include accumulated foreign substances having different compositions or adhered, and shape deformation caused by scratches on the film. Hereinafter, for the sake of simplicity, the structure in the height direction of the sample is expressed as a film, but in this specification, the film widely refers to a structure having the same composition.

  Next, a method for measuring or observing the uneven shape on the sample surface will be described with reference to FIG. Here, the sample surface is identifiable depth information that depends on the resolution of the apparatus used, and depends on the acceleration voltage and the like. For example, in the case of using secondary electrons, the generation depth of secondary electrons (about 10 nm) is generally shown, but in the case of reflected electrons, information deeper than that can also be detected. The sample surface is the above-described region and indicates a state where there is no structure on the top of the sample being observed. The internal structure represents a structure that is not physically exposed from the sample. For example, it refers to a sample structure that can be detected below the “sample surface” described above, that is, at a depth (penetration length) at which a primary electron beam for observing an uneven shape enters. When some particles are present in the film, if the upper part of the particle is exposed from the film surface, the exposed part is the “sample surface”, and the area that can be recognized as the film covering the upper part of the particle is “sample "Inside". FIG. 3 is a diagram for explaining the outline of measurement of the uneven shape on the sample surface. FIG. 3A shows an example in which uneven shape measurement is performed using an annular backscattered electron detector divided into four. The sample 301 is irradiated with the electron beam 302, and the reflected electrons 304 are detected by a four-part reflected electron detector 303 disposed immediately above the sample 301. The amount of reflected electron signals acquired by each detection element 305 of the four-part reflected electron detector varies depending on the sample unevenness, material, etc., but the signal amount acquired by the four detection elements is calculated at an arbitrary measurement point on the sample. Thus, various unevenness information on the sample surface can be constructed.

The detection signals of the detection elements 305A to 305D of the four-part reflected electron detectors arranged to face the sample reflect the tilt information of the sample. In order to obtain the unevenness information, for example, the height distribution Z (P2) can be obtained by performing two-dimensional integration in the X and Y directions from the respective detection signals as shown in the following equation. Note that x ₀ , x ₁ , y _{0 and} y ₁ are two-dimensional positions, respectively, and Z (P ₀ ) is the height at the origin (x ₀ , y ₀ ).

  Here, the unevenness information is an SEM image 306 in which the unevenness can be recognized as shown in FIG. 3B, a bird's eye view 307 showing the unevenness easily as shown in FIG. 3C, and an SEM image as shown in FIG. There is a cross-sectional profile 308 extracted with an arbitrary line. The cross-sectional profile 308 is a two-dimensionally cut out SEM image in an arbitrary direction including the Z direction, and shows the distribution of the sample height in that direction.

  Among these, the baseline height 309 is shown in the cross-sectional profile 308 of FIG. The acquired unevenness information is represented by a relative height displacement based on the baseline height 309. The baseline height 309 starts from a position where the difference in signal amount detected by each detection element 305 of the backscattered electron detector divided into four becomes zero, or a calibration position set as a reference height. The baseline height 309 may be expressed as an absolute reference height by using a calibration sample whose absolute value is known. Further, by creating the cross-sectional profile 308 in a plurality of directions, the unevenness information 310 can be extracted as a numerical value from any pixel in the acquired image. When the sample set is tilted, an error factor may be added to the uneven shape of the sample surface and the internal structure may be distorted. However, the sample tilt is corrected by using the baseline height 309 as a reference. It is also possible to adjust the level and grasp the original internal structure.

  Here, the reflected electron detector is divided into four parts, but if the number of divisions is two or more, the azimuth angle of the reflected electrons emitted from the sample can be discriminated and detected, and the present invention is not limited to this. In addition to the above-described method, various methods such as a method of acquiring a stereo image by sample inclination or beam inclination are applicable as a method for measuring the uneven shape of the sample surface.

  Now, in order to observe the internal structure of a sample, conventionally, it is often necessary to cut the sample, which is accompanied by destruction or disappearance of the sample. In particular, when analyzing foreign substances contained in the sample, in the preparation of a physical cross-section such as the above-mentioned cutting method, stress is applied by contact or friction of a blade or the like for cutting the sample. There was a risk of causing a change in shape such as deformation or dropout of the target foreign matter.

  Further, in the observation of the concavo-convex shape as shown in FIG. 3, most of the information in the vicinity of the sample surface occupies and the internal structure of the sample cannot be analyzed. In the case of a sample with a uniform film thickness and a smooth substrate surface, it may be possible to estimate the presence of internal foreign matter by grasping the uneven shape of the sample surface, but the smoothness of the substrate and sample surface is assumed. Therefore, in reality, it is difficult to determine whether or not the unevenness of the sample surface is caused by foreign matter embedded inside. Even when a foreign object is embedded inside a sample with a smooth substrate and sample surface, for example, when a triangular object is embedded, the top of the triangular object is upward or downward with respect to the sample. Even so, since the unevenness of the sample surface shows the same shape, it is difficult to accurately grasp the entire shape of the foreign matter.

  In this example, the internal structure of the sample is analyzed based on the information on the uneven shape of the sample surface and the thickness of the portion having the same composition. Information on the uneven shape of the sample surface can be analyzed from the image of the sample based on the secondary signal, and the thickness of the part having the same composition is evaluated by analyzing the composition in the thickness direction of the sample by elemental analysis etc. be able to. In the following, “thickness” can also be referred to as “depth”.

  In particular, in this embodiment, the thickness of each sample composition is measured at a plurality of points on the sample.

  As a result, the in-plane distribution of the internal structure of the sample in the plane parallel to the substrate can be grasped, and as a result, the internal structure can be constructed for the local region of the sample from these analysis results. Therefore, according to this embodiment, the internal structure can be measured or observed without destroying the sample.

  A flowchart showing an example of the internal structure analysis of the sample is shown in FIG.

  A sample to be analyzed is loaded into a sample chamber of a scanning electron microscope. Next, the sample stage of the scanning electron microscope is moved to specify the analysis target portion (step 401). The analysis target portion refers to a region set as a range for analyzing the internal structure. The analysis target portion may be designated by the user, or may be designated in advance by a recipe in which inspection conditions are set, and may be automatically set. Alternatively, by using an external image other than the scanning electron microscope image, such as an optical microscope image or digital camera image having color information, position information output from the device from which the external image was acquired is set as an analysis target location. Is also possible.

  Next, the uneven shape measurement of the sample surface is performed at the analysis target part (step 402), the reference height information is acquired (step 403), and the sample surface unevenness information is acquired (step 404). Steps 402, 403, and 404 are performed by the method described with reference to FIG. 3, for example. Here, the reference height information means a position where the difference in signal amount detected by each detection element 305 of the backscattered electron detector divided into four becomes zero, or a calibration position set as a reference height. The unevenness information refers to the difference between the height information calculated at each measurement point and the reference height information.

  Next, elemental analysis is performed at the same analysis target location as the position where the uneven shape was observed (step 405), the composition in the thickness direction of the sample is analyzed, and information on the thickness of the portion having the same composition (hereinafter referred to as structure) The object thickness information is acquired (step 406). In addition to the film, the structure includes an artificial pattern and a foreign substance included in the sample. Acquisition of structure thickness information (step 406) by three-dimensional shape measurement (step 402) and elemental analysis (step 405) is performed at the same analysis target without moving the sample position, so data acquisition is easy. It can be performed. Note that the same analysis target position as the position where the uneven shape is observed includes a case where element analysis is performed on a part of a plurality of positions where the uneven shape is observed to obtain thickness information of the structure. The acceleration voltage for performing the elemental analysis (step 405) is calculated from information such as the element constituting the sample, the density, the film thickness, and the conditions for reaching through the structure to be analyzed are automatically selected. When observing the concave / convex shape on the sample surface, the same acceleration voltage as in elemental analysis may be used, or in order to clearly grasp the sample shape, measurement may be performed by changing the acceleration voltage.

  The reference height information by the three-dimensional shape measurement (step 402), the sample surface unevenness information, and the thickness information of the structure by the elemental analysis (step 405) are added and subtracted (step 407). Obtain the calculated position information of the structure. Next, the internal structure of the sample is constructed by plotting the position information of the structure calculated from the reference height at each measurement point obtained by each measurement, and plotting it into a graph or a three-dimensional diagram (step 408). Can do.

  The internal structure of the sample that is finally constructed here is, for example, information on the shape, size, position of foreign matter, and orientation of foreign matter when a triangular pyramid-like foreign matter is contained between the substrate and the film. Indicates.

The calculation for constructing the internal structure of the sample is performed by adding / subtracting the uneven shape information on the surface of the sample and the thickness information of the structure. An example is as follows.
Sample surface shape: [reference height-uneven information on sample surface]
Structure 1 shape: [reference height-sample surface irregularity information + structure 1 thickness information]
Structure 2 shape: [reference height-sample surface unevenness information + structure 1 thickness information + structure 2 thickness information]

  Hereinafter, when the total number of structures increases, the thickness information is added to each structure, the sample surface shape, the structure 1 to the structure n are analyzed, and the internal structure is obtained by adding and subtracting the information. Can be built.

  Uneven shape information and film thickness information obtained from composition analysis can be obtained by calculation with a scanning electron microscope control PC or analysis control PC that acquired the image and composition analysis information, or can be calculated with an externally connected PC or a single PC. is there. Even when the internal structure information is constructed based on these pieces of information, it can be constructed by each of the control PCs described above, an externally connected PC, or a single PC.

  FIG. 5 shows an analysis example of a sample containing a foreign substance as an example of the internal structure analysis of the sample. In this example, the foreign matter and the film correspond to the “structure” described above. A foreign substance 503 is included in a film 502 formed of one layer or a plurality of layers having different compositions formed on the substrate 501. The electron beam 504 is scanned so as to include a sample surface region that is vertically above the foreign material 503, and information on the uneven shape of the sample surface is acquired. In FIG. 5, the scanning with the electron beam 504 is performed in the order of 1-9 indicated by the round letters in FIG. 5 so as to cross the sample surface region which is vertically above the foreign substance 503. Here, the sample surface area that is vertically above the foreign substance 503 is, for example, an area irradiated with an electron beam in circles 3-7 in FIG. The region including the foreign object 503 to be analyzed is confirmed by various observations such as visual inspection by the user, an inspection apparatus, an optical microscope, a stereomicroscope, a metallographic microscope, and an X-ray image, or the presence of foreign objects is confirmed by unevenness of the sample surface. Infer. The uneven shape information on the sample surface can be acquired by the method described with reference to FIG. 3, for example. Thereby, the sample surface unevenness information 505 and the sample reference height 506 can be acquired.

  Next, the electron beam 507 is irradiated so as to include a sample surface region that is vertically above the foreign material 503, and film thickness information 508 and foreign material thickness information 509 are obtained at each electron beam 507 irradiation site. The film thickness information 508 and the foreign substance thickness information 509 can be acquired by, for example, the method described with reference to FIG.

  In addition, if the uneven | corrugated shape information and film thickness information are analyzed at one place on the sample, the internal structure of the sample in that region can be constructed. Further, as shown in the present embodiment, a two-dimensional internal structure can be constructed by analyzing the concavo-convex shape information and the film thickness information at a plurality of locations on one straight line. Furthermore, if the surface unevenness information and film thickness information are acquired at least at three points that are not on the same straight line, the internal structure of the sample can be constructed in three dimensions.

  The method for selecting the analysis region for the uneven shape information and the film thickness information may be a configuration in which the user selects in advance, or the region may be automatically selected. As a method for automatically selecting a region, it is possible to set the position based on the foreign object position based on the composition contrast based on the backscattered electron image of the scanning electron microscope or the specific position information of the foreign object from which the external image is acquired.

  In particular, when the sample contains foreign matter, at least a first region that is vertically above the foreign matter and a second region other than the first region on the sample are selected as the analysis region. Good. The uneven shape information and the film thickness information may be analyzed in a region having a certain range or a point shape. In this specification, the analysis region includes a dotted region.

  Next, the obtained information is summed. First, sample surface information is acquired from the reference height-surface unevenness information 510 with the reference height 506 as the origin 0. Further, film information is obtained by reference height-surface unevenness information + film thickness information 511, and foreign object information is obtained by reference height-surface unevenness information + film thickness information + foreign film thickness information 512 and plotted. Thus, the internal structure reconstruction result 513 of the sample is obtained. Here, the film information refers to the position in the depth direction of the film at each measurement point, and the foreign matter information refers to the size of the foreign matter and the buried depth position. In FIG. 5, for the sake of simplicity, the number of electron beam irradiation points is only nine. However, a fine sample shape can be grasped by increasing the number of measurement points for the uneven shape of the sample surface and film thickness information.

  Further, when the electron beam 507 is irradiated in a line shape, two-dimensional cross-sectional information is obtained, and when the electron beam 507 is irradiated in a grid shape, a three-dimensional internal structure can be grasped.

  According to the above embodiment, since the internal structure can be analyzed only by the surface observation device provided with the three-dimensional shape measuring means and the film thickness measuring means, a special individual device such as mechanical polishing and ion milling for cross-section preparation is provided. The internal structure of the sample (film thickness, foreign material shape, etc.) can be grasped easily and non-destructively.

  In the above-described embodiments, not only foreign substances contained in the sample, but also evaluation of the shape of multilayer films and wiring materials typified by semiconductor devices, evaluation of the internal shape of dispersion materials mixed to improve resin strength, etc. It is also applicable to. A relatively large internal structure can be evaluated by using X-ray CT or the like, but it is often difficult to deal with resolution in a semiconductor device or the like that is miniaturized. On the other hand, since this method is an analysis using a scanning electron microscope, it can be easily handled by using a higher-resolution scanning electron microscope.

  According to the present embodiment, the internal structure of the sample can be grasped regardless of the smoothness of the sample and the substrate and the presence or absence of the conductivity of the sample constituent material.

  In this embodiment, an example of observing a sample that easily proceeds in the atmosphere and a sample that is easily contaminated will be described. Examples include lithium ion battery materials and highly active metal materials.

  In the case of a sample in which the internal tissue or contained foreign matter is easily altered by exposure to the atmosphere, the internal structure or contained foreign matter may be exposed during cross-section preparation, which may cause alteration. In the case of such a sample, conventionally, when the sample is transported to the cross-section preparation device and the charged particle beam device for observation, the work is performed using a sample transport device that can shut off the atmosphere. Special equipment is required, and the work may be complicated. If the structure of the sample surface layer is likely to change, it is possible to analyze the sample surface structure as a laminated film structure including a protective film by forming a protective film on the surface of the sample by coating with a metal such as Pt or C, for example. is there.

  Even in such a sample, by observing the internal structure of the sample with the scanning electron microscope according to the present invention, the internal structure can be grasped by observing / analyzing from the sample surface without exposing the internal structure.

  When the foreign substance contained in the sample is non-conductive, a charging phenomenon is likely to occur on the sample surface due to the irradiation of the primary electron beam. This charging phenomenon hinders primary electron beam irradiation or generation of secondary signals, which may contribute to sample drift and increase / decrease in the amount of signal generation, thereby hindering sample cross-section preparation and sample observation. When acquiring surface unevenness information and film thickness information, there arises a problem that an error or the like occurs in a position shift due to a sample drift based on a charging phenomenon, or an uneven shape calculation and film thickness measurement result due to increase / decrease in signal generation amount.

  On the other hand, as in this embodiment, the charged particle beam device is accompanied by a charge reducing function by adjusting the degree of vacuum in the sample chamber, so that even if the material constituting the sample has low conductivity, the influence of the charge is exerted. Observation or analysis with reduced is possible.

101 Electron gun 102, 203, 209, 302, 504, 507 Electron beam 103 Converging lens 104 Deflector 105 Objective lens 106, 301 Sample 107 Secondary signal 108 Backscattered electron detector 109, 206 X-ray detector 110 Secondary electron detection 111 Display unit 112 Control PC
201, 501 Substrate 202, 502 Film 204 X-ray generation region 205 Characteristic X-ray 207 Film thickness information 208 Recess 210 Film thickness information at a plurality of points 303 Quadrant reflected electron detector 304 Reflected electron 305 Detector element 306 SEM image 307 Bird's eye view 308 Cross-sectional profile 309 Baseline height 310 Concavity and convexity information 503 Foreign matter 505 Surface unevenness information 506 Reference height 508 Film thickness information 509 Foreign matter thickness information 510 Reference height−surface unevenness information 511 Reference height−surface unevenness information + film Film thickness information 512 Reference height-surface unevenness information + film thickness information + foreign matter thickness information

Claims (13)

A charged particle beam apparatus that irradiates a sample with a charged particle beam and generates an image of the sample from a secondary signal generated by the irradiation,
An uneven shape analyzer for analyzing the uneven shape of the surface of the sample from the image,
A composition analysis unit that analyzes the composition in the thickness direction of the sample in an arbitrary region of the sample and evaluates the thickness of a portion having the same composition;
A charged particle beam apparatus comprising: an internal structure constructing unit configured to construct an internal structure of the sample based on a thickness of a portion having the same composition as the uneven shape in the region. The charged particle beam apparatus according to claim 1,
The uneven shape and the thickness of the portion having the same composition are analyzed at a plurality of locations on the sample,
The charged particle beam apparatus characterized in that the internal structure is constructed in two dimensions or three dimensions. The charged particle beam apparatus according to claim 2,
The sample contains a foreign substance,
The charged particle beam apparatus according to claim 1, wherein at least a first region that is vertically above the foreign substance and a second region other than the first region on the sample are selected as the plurality of locations. The charged particle beam apparatus according to claim 1,
The internal structure constructing unit constructs the internal structure of the sample by adding or subtracting the thickness of a portion having the same composition as the uneven shape. The charged particle beam apparatus according to claim 1,
The charged particle beam apparatus characterized in that the uneven shape is expressed by a predetermined reference height and a relative displacement from the reference height. The charged particle beam device according to claim 1, further comprising:
A charged particle beam apparatus comprising a display unit for displaying the internal structure. The charged particle beam device according to claim 1, further comprising:
A charged particle beam apparatus comprising means for relaxing charging of the sample. A sample observation method for irradiating a sample with a charged particle beam and generating an image of the sample from a secondary signal generated by the irradiation,
Analyzing the concavo-convex shape of the surface of the sample from the image;
Analyzing a composition in a thickness direction of the sample in an arbitrary region of the sample, and evaluating a thickness of a portion having the same composition;
And a step of constructing an internal structure of the sample on the basis of the thickness of the concave and convex shape in the region and the portion having the same composition. The sample observation method according to claim 8,
The uneven shape and the thickness of the part having the same composition are analyzed at a plurality of points on the sample,
The sample observation method, wherein the internal structure is constructed in two dimensions or three dimensions. The sample observation method according to claim 8,
The sample observing method is characterized in that the step of constructing the internal structure constructs the internal structure of the sample by adding or subtracting the thickness of a portion having the same composition as the uneven shape. The sample observation method according to claim 8,
The sample observation method, wherein the sample has a layer structure of a single layer or a multilayer film. The sample observation method according to claim 8,
A sample observation method, wherein the sample contains a foreign substance. The sample observation method according to claim 8,
A sample observation method, wherein the internal structure of the sample is a material that changes in quality when exposed to the atmosphere.