KR20210013142A - Inspection system and inspection method for verifying semiconductor structure - Google Patents

Abstract

The inspection system 1 serves to verify the semiconductor structure. The inspection system has an ion beam source 2 for spatially resolved exposure of the structure to be verified with an ion beam 3. Further, a secondary ion detection device 12 comprising a mass spectrometer 13 is provided. The mass spectrometer 13 is capable of measuring the ion mass to charge ratio in a given bandwidth.

Description

Inspection system and inspection method for verifying semiconductor structure

This application claims priority to US provisional application US 62/689 329 as well as German patent application DE 10 2018 212 403.5, the contents of which are incorporated herein by reference.

The present invention relates to an inspection system for qualifying a semiconductor structure. Further, the present invention relates to an inspection method for verifying a semiconductor structure.

(eds.), Helium Ion Microscopy, Nanoscience and Technology, Springer International Publishing, Switzerland, 2016]으로부터 공지되어 있다. WO 2008/152 132 A2호는 2차 이온 질량 분광법을 수행하기 위한 장치 및 방법을 개시하고 있다.Inspection systems and also inspection methods for verifying 3D semiconductor structures are known from US 2007/0221843 A1 and US 2009/0114840 A1, and also [G. Hlawacek and A.

(eds.), Helium Ion Microscopy, Nanoscience and Technology, Springer International Publishing, Switzerland, 2016]. WO 2008/152 132 A2 discloses an apparatus and method for performing secondary ion mass spectroscopy.

It is an object of the present invention to improve such inspection systems for verification of semiconductor structures, in particular for verification of 2D or 3D semiconductor structures.

This object is achieved by an inspection system comprising the features of claim 1.

It is recognized that the use of an ion beam source to generate secondary ions to be detected by a mass spectrometer together with the use of a mass spectrometer to simultaneously measure the ion mass to charge ratio at a given bandwidth provides a powerful tool for verifying semiconductor structures. Became. The bandwidth at which the simultaneous measurement of the ion mass to charge ratio is performed through a mass spectrometer is the band of the ion mass to charge ratio between the lower limit of the ion mass to charge ratio and the upper limit of the ion mass to charge ratio. The system can be used to verify 2D and/or 3D structures. The system is capable of placing a well defined localized ion beam on the object or sample to be verified. In addition, the system can also correlate high-resolution secondary ion imaging on the one hand with analytical information obtained through mass spectroscopy on the other. To this end, the system may include secondary electron imaging optics. The secondary ion mass spectrometer involved here provides the possibility to simultaneously track different ion mass-to-charge ratios and thus provide individual information for different materials and/or elements and/or isotopes present in the sample area. In addition, it has been recognized that the results of this inspection system are not compromised by the use of a low current ion beam, which can have a high spatial resolution and also a very small focal diameter. The spatial resolution may be 100 nm or more, 50 nm or more, or 20 nm or more. The focal diameter of the ion beam may be less than 10 nm, less than 5 nm, less than 2 nm, less than 1 nm, or even less than 0.5 nm. The inspection system may also be used as part of an apparatus for examining and/or removing defects in the verified semiconductor structure. The inspection system may be used for examination of a specific structure, for example for inspection and review of a solid aspect ratio (HAR) contact coil. These inspection and review steps may occur during the manufacturing process of each semiconductor structure.

The inspection system according to the invention has a wide range of applications. Some of these are described below:

One application is to measure the critical dimension (CD) using secondary ion mass spectroscopy (SIMS), which ranges according to the increasing complexity and range of materials used in semiconductor devices. Due to the use of a mass spectrometer, the inspection system is capable of distinguishing elements based on mass. This can be utilized to complete conventional CD measurements of semiconductor devices that do not yield any elemental/chemical information. The secondary electron yield of traditional ion microscopy provides only gray levels per element for qualitative analysis.

Another application of the inspection system according to the invention is organic film characterization. This application relates to inductive self-assembly (DSA) for wafer patterning. These DSA vapors have often used block copolymers to form structures with conventional dimensions of 10 nm to 100 nm (nanoscale). Distinguishing the different types of organic polymers on the nanoscale is very important in the development of methods for using DSA. The inspection system according to the invention has the ability to directly distinguish different types of polymers using characteristic fingerprints measured with a mass spectrometer.

Other applications for inspection systems are single and buried defect detection. The detection and analysis of the chemical composition of a single defect on the wafer is important to approach the cause of these defects. In addition, the buried defect and chemical information about the surrounding layer can be determined by the inspection system.

Another application for inspection systems is characterization of etch residues. This analysis of the etch residue on the wafer provides valuable information. In particular, stoichiometric fluctuations in etch chemistry are of interest to determine the cause of incomplete/defective etch or defective subsequent process steps caused by etch residues within a confined volume such as trenches, holes, corners, etc. Using the inspection system according to the invention, which may have high spatial resolution and/or high surface sensitivity, makes it possible to investigate stoichiometric variations across various device topologies.

The provision of a mass spectrometer capable of continuously measuring the ion mass to charge ratio according to claim 2 further improves the information output of the inspection system. At the selected mass-to-charge ratio bandwidth, all ion mass-to-charge ratios present therein can be detected simultaneously. The selected ion mass-to-charge ratio bandwidth may include a bandwidth capable of simultaneously detecting elemental silicon, titanium, copper, selenium and tellurium antimony. The resulting mass bandwidth may be in the range of 1 u (integrated atomic mass units) to 500 u.

The secondary electron detection unit according to claim 3 enables secondary ion detection with high accuracy and high efficiency. The useful yield, ie the ratio between the number of secondary ions that can be measured via the inspection system on the one hand and the number of sputtered particles produced by the ion beam on the other, may be high. Useful yields may range from 10 ^-5 to 0.1.

Ion beams according to claims 4 and 5 have proven to be particularly useful in inspection systems.

The secondary ion transfer unit according to claim 6 enables an exchange between a semiconductor structure generation mode of an apparatus that can be used as a projection exposure apparatus and an inspection mode further having a secondary ion transfer unit at the delivery location. This allows for inline inspection during the semiconductor production process.

The total ion counter according to claim 7 provides for example ratio information on the distribution of occurrences of different elements in the sampled area.

The extended detector array according to claim 8 provides a high spatial resolution of the secondary ion detection device which can lead to high mass resolution. The detector array may be implemented as an array of channel electron multipliers (CEM) or as micro-channel plates (MCPs).

Another object of the present invention is to improve an inspection method for verifying semiconductor structures, in particular for verifying 2D or 3D semiconductor structures.

This object is achieved by the inspection method according to the step of claim 9.

On the one hand, the combination of the schematic review of the structure to be verified and the detailed review of the verification volume candidates identified in the schematic review step using an ion beam and a secondary ion detection device is the sample area/volume to be reviewed in detail with high accuracy and high information values. It has been recognized as enabling the examination of The volume to be reviewed in detail can be selected using a coarse review step, which may be performed via secondary electron microscopy images. A detailed review based on the ion beam and the secondary ion detection device may then be performed based on the schematic information derived from the schematic review. Performing continuous mass spectroscopy leads to the possibility of collecting detailed element distribution information of the volume to be reviewed in the detailed review step. By this inspection method, on the one hand, it is possible to evaluate the quality of the semiconductor structure to be verified by use of the result of the schematic review of the structure to be verified and on the other hand the detailed review result of the verification volume candidate identified in the schematic review step.

The lateral spatial resolution according to claim 10 provides high information values. Small structural details that may correspond to the resolution of the semiconductor structure process may be examined in detail.

The focal diameter according to claim 11 has corresponding advantages.

The advantage of the inspection method is very effective when the inspection method is performed in-line during the semiconductor production process according to claim 12. Additionally or alternatively, the inspection method may be used to perform failure analysis through the object or sample surface and/or to perform defect detection. Such failure analysis/defect detection may also be performed in an offline mode, ie not during the semiconductor production process.

The advantages of the inspection method according to claim 13 have already been described above.

Microscopic imaging according to claim 14 as part of the inspection method allows a depiction of the material distribution, and different materials contributing to this distribution are also inferred from continuous mass spectroscopy. This electron microscopy imaging then allows visualization of the distribution of various materials identified via continuous mass spectroscopy.

Exemplary embodiments of the present invention are described below with reference to the drawings. In the drawing:
1 shows a schematic diagram of a beam/particle interaction in an inspection system to verify a 3D semiconductor structure.
2 is a further schematic diagram of the main components of the inspection system.
3 is a section of a microscope image obtained from an inspection system from secondary electrons generated by the inspection system.
FIG. 4 is a plot of the time-resolved count rates of three different ion energies measured by the mass spectrometer of the inspection system at three different locations within the object section shown in FIG. 3.
5 is another section of an object imaged with secondary electrons by the inspection system prior to the object milling step with an ion beam, on a larger scale compared to FIG. 3.
FIG. 6 is a section according to FIG. 5 after a milling step showing three different milled rectangular sections.
7 is the section of FIG. 6 with the milled area highlighted.
FIG. 8 is a time-resolved diagram corresponding to FIG. 4, showing the temporal evaluation of three different measured ion energies derived from the first region highlighted in FIG. 7.
FIG. 9 is a time-resolved diagram corresponding to FIG. 4, showing the temporal evaluation of three different measured ion energies derived from the second region highlighted in FIG. 7.
FIG. 10 is a time-resolved diagram corresponding to FIG. 4, showing the temporal evaluation of three different measured ion energies derived from the third region highlighted in FIG. 7.

1 and 2 show the principle of operation and main components of an inspection system 1 for verifying a three-dimensional (3D) semiconductor structure, in particular for verifying a lithographic photomask. Such photomasks may be particularly suitable for EUV projection lithography.

The inspection system 1 has an ion beam source 2 schematically shown in FIG. 1. This ion beam source 2 is a plasma source having a well defined source volume. An example of such an ion beam source is disclosed in US 2007/0221843 A1. The ions produced by the ion beam source are rare gas ions, especially helium or neon ions. Other noble gases including argon, krypton or xenon may likewise be used by providing the respective ion beam source.

The ion beam source produces an ion beam 3 with well defined directivity characteristics. The spatial resolution obtained by this ion beam 3 is 20 nm or more. The ion beam 3 is focused on an objective field 4 on the surface 5 of an object or sample 6 having a 3D structure to be verified by the inspection system 1. The focal diameter of the ion beam 3 is less than 0.5 nm.

The ion beam may have an energy in the range of 2.5 keV to 30 keV, for example 25 keV. The beam current of the ion beam may be in the range of 1 to 100 pA, in particular in the range of 10 pA.

1 schematically shows the interaction of the material of the object 6 and the focal ion beam 3 in the objective field 4. Three kinds of atoms 7, 8, 9 are shown sputtered from the objective field of the surface 5 by the ion beam 3. Atom 7 is positively charged. Atom 8 is neutral. Atom 9 is negatively charged. A number of secondary electrons (SE) generated during the sputtering and indicated by e- in FIG. 1 are also shown. A beam interaction area 10 is also shown in FIG. 1, wherein the interaction between the ion beam 3 and the material of the object 6 takes place during the sputtering process.

The Cartesian x/y/z coordinate system is also shown in FIG. 1. The coordinates x and y span the surface 5 of the object 6. The coordinate z is perpendicular to this x/y surface plane.

This beam interaction region 10 is a very well defined volume with an x/y-dimension in the range of 5 nm to 50 nm and a z-dimension in the range of 5 nm to 50 nm. The inspection system 1 comprises a secondary electron optics 11 capable of generating secondary electron images of the objective field 4. Such secondary electron optics are also disclosed in US 2007/0221843 A1. The system 1 may also have a projection optical system of a projection exposure apparatus for EUV lithography. During this semiconductor manufacturing process, a three-dimensional structure can be created by imaging the reticle on the objective field 4 with a projection exposure apparatus using a projection optical system.

The inspection system 1 further comprises a secondary ion detection device 12 for detecting secondary ions, in particular charged atoms 7, 9 arising from ion beam sputtering. The secondary ion detection unit 12 includes a mass spectrometer 13. The mass spectrometer 13 is capable of secondary ion mass spectroscopy (SIMS). This mass spectrometer 13 makes it possible to measure the ion mass-to-charge ratio of secondary ions in a given bandwidth, in particular to keep measuring it. This is schematically illustrated in FIG. 2 showing secondary ion beam paths 14, 15, 16, 17 corresponding to different ion mass to charge ratios. After the secondary ions are collected by the extraction optics, they are uniformly accelerated towards the magnetic sector, for example at 3 kV.

The beam path 14 is related to the minimum detectable ion mass. The beam path 17 is associated with the maximum detectable ion mass. Between this minimum and this maximum ion mass, there is a continuous ion mass bandwidth 18 detectable by the mass spectrometer 13.

A diagram showing the result of the cumulative count of this ion mass for charging the bandwidth 18 after a specific measurement period of the inspection system 1 is schematically shown in FIG. 2. The cumulative count rates for various different ion mass to charge ratios corresponding to each different element are shown. To measure the ion energy, the mass spectrometer 13 comprises a secondary electron detection unit 19 comprising a total ion counter. The secondary ion detection unit 19 is implemented as an extended detector array. An example of such a detector array is an array of channel electron multipliers (CEMs). The secondary ion detection unit can be used with 4 or more such channel electron multipliers, for example 4, 5, 6, 8, 10, 15, 20, 25, 30, 50, 75, 100 or even a greater number of channel electrons. It may also include a multiplier. The secondary ion detection unit 19 is implemented as a micro-channel plate (MCP) having more than 50, more than 100, more than 200, more than 500, more than 1000, more than 2000 or even more than 4000 channels. It could be.

The secondary ion detection unit further includes a secondary ion transfer unit 20. This secondary ion transfer unit 20 includes secondary ions (i.e., charged atoms 7, 9) coming out of the beam interaction region, i.e., the target volume of the probe structure to be verified. ) To the mass spectrometer 13, in particular to the secondary ion detection unit 19, the first position shown in FIG. 2, and the secondary ion transfer unit 20 generated in the beam interaction region. It is movable between an electron and/or secondary ion and a second neutral position that does not react. In order to achieve this mobility of the secondary ion transfer unit 20 between the first transfer position and the second neutral position, the secondary ion transfer unit 20 interacts with the drive 21.

The secondary ion transfer unit 20 comprises a first deflecting means 22 located directly above the beam interaction region 10 at the delivery position of the secondary ion transfer unit 20. The deflection means 22 comprise through channels for passing the ion beam 3 in the beam path between the ion beam source 2 and the beam interaction region 10. In addition, the secondary ion transfer unit 20 comprises a beam tube 23 for encapsulating the secondary ion beam path between the deflection means 22 and the mass spectrometer 13. The mass spectrometer 13 itself comprises two different deflection means 24, 25, which deflecting means are magnetic for diffusing the secondary ion beam paths 14 to 17 onto the secondary ion detection unit 19. It serves as a sector. The secondary ion detection unit 19, ie CEM, is arranged in the focal plane of the magnetic sector 25. CEMs are used to directly measure secondary ions with different trajectories based on their mass-to-charge ratio (compare beam paths 14-17 in FIG. 2).

The deflection means 22 is implemented as an electrostatic sector.

The deflection means 24 are implemented as an electrostatic sector.

Secondary ions are collected from the sample 6 and electrostatically focused, accelerated, and projected onto the focal plane of the secondary ion detection unit 19. The mass spectrometer 13 may also have a Mattauch-Herzog design.

In a typical mode of operation of the system 1, the magnetic field of the magnetic sector 25 and the position of the secondary electron detection unit 19 are kept constant, and the counting factor for each channel of the secondary ion detection unit 19 is It is measured while buffering the sample 6 to obtain volume information for this sample.

The mass resolution of the mass spectrometer 13 is sufficient to distinguish not only different elements but also individual isotopes.

The measurement of the ion mass-to-charge ratio bandwidth may be generated in an alternative mode of operation, by sweeping the magnetic field of the magnetic sector 25 and/or by moving an individual detector or the entire secondary ion detection unit 19.

(eds.), Helium Ion Microscopy, Nanoscience and Technology, Springer International Publishing, Switzerland, 2016], 특히 [chapter 13 of Tom Wirtz et al. "SIMS on the helium ion microscope: The powerful tool for high-resolution high-sensitivity Nano-analytics"]에 개시되어 있다.In particular, embodiments of the deflecting means 24 and 25 and the secondary ion transfer unit are described in [G. Hlawacek and A.

(eds.), Helium Ion Microscopy, Nanoscience and Technology, Springer International Publishing, Switzerland, 2016], in particular [chapter 13 of Tom Wirtz et al. "SIMS on the helium ion microscope: The powerful tool for high-resolution high-sensitivity Nano-analytics"].

Using the inspection system 1, an inspection method for verifying a 3D semiconductor structure is described below with reference to FIGS. 3 to 10.

The inspection method includes a rough review step of the structure to be verified.

3 shows an example of such a schematic review inspection step. A section of the object 6 to be verified is shown. This sample area 26 of the object 6 is created using conventional secondary electron microscopy techniques using the secondary electron optics 11 of the inspection system 1. The object 6 to be inspected comprises a number of structural areas. The subregions "1", "2" and "3" of these object structures to be further examined are highlighted in FIG. 3.

Subregion "1" contains the ridge structure shown in an electron microscope imaging a plug of some kind without further definition. Subregion "2" represents a corresponding ridge without such a plug. Sub-area "3" is an example of a plurality of "by-product" structures present in multiple places on the sample area of the object 6 during the rough review step.

These highlighted sub-areas "1", "2" and "3" serve as candidates for verification volumes identified in the rough review step. Among the inspection methods, these sub-areas "1", "2" and "3" now experience more detailed review during the inspection method. During this detailed review, spatially resolved ion beam sputtering in the volumes of each of the sub-regions "1", "2" and "3" directs the ion beam 3 to these sub-regions "1", "2" and "3". It is done by orientation. For each of these subregions "1", "2" and "3", secondary ions (compare secondary ions 7 and 9 in Fig. 1) during detailed examination are detected in time-resolved measurements. These detected secondary ions are continuous using a secondary ion transfer unit and a mass spectrometer 13, i.e. using the secondary ion detection device 12 of the inspection system 1 as described above with reference to FIG. Experience mass spectrometry.

4 shows time-decomposition results of detailed examination for sub-areas "1", "2", and "3". In the figure of FIG. 4, the coordinates are measured counting rates given in counts per second (CPS).

During the measurement, the ion beam 3 is directed to the subregion "1" in the first time period T ₁ , and directed to the subregion "2" in the next time period T ₂ , and the third and last time period It is directed to sub-region "3" at (T ₃ ).

The counting factor, shown as a solid line, is provided at the first ion energy level of the mass spectrometer 13 corresponding to silicon (Si). The counting factor, shown as a dotted line, is provided for the ion energy corresponding to titanium (Ti). The counting factor, shown as a dashed-dotted line, is provided for the ion energy corresponding to copper (Cu).

The time-decomposition coefficient according to FIG. 4 further provides information on the depth distribution of occurrence of each of the elements Si, Ti, and Cu. In sub-region "1", titanium and copper are present on the immediate surface. As the ion beam 3 is milled just below the surface of the subregion "1", the generation of titanium and copper decreases and the generation of the base material silicon increases to dominate after a short sampling time.

In sub-region "2", no titanium is present, and the time-resolved behavior of the counting rate related to silicon and copper is similar to that of the measurement of sub-region "1". From the comparison of the measurements of the sub-regions "1" and "2", it can be inferred that the plug shown in the secondary electron micrograph of FIG. 3 is a titanium plug.

Measurements at the "by-product" position of subregion "3" reveal that there may be traces of titanium just above the resolution limit of the mass spectrometer 13. The time-decomposition behavior with respect to the presence of silicon and copper is similar to that of subregions "1" and "2". From the comparison of the counting rate measurements of sub-region "3" and those of sub-regions "1" and "2", it can be concluded that the "by-product" shown in the secondary electron microscope image of FIG. 3 is titanium.

The lateral spatial resolution for the above detailed examination steps is better than 100 nm, in particular 75 nm or more, 50 nm or more and 30 nm or more. The lateral spatial resolution, ie the resolution in x and y, can be 20 nm or even more. The depth resolution (z direction) depends on the milling speed of the ion beam 3 in the material of the object 6. This depth resolution can also be in the range of 100 nm or even more.

The accuracy of the surface area to be irradiated by the ion beam 3 in the objective field 4 may be 5 nm or more, 3 nm or more, and even 1 nm or more. This accuracy is particularly crucial when attempting to capture probe structures such as "by-product" in subregion "3". These more or less point-like sub-areas are detected through a rough review, and their coordinates are then determined by the inspection system 1 to ensure that the beam interaction area 10 is accurately positioned in that sub-area, for example sub-area "3". ) Is supplied to the relative positioning control. To this end, the object 6 is placed in a high position xyz coordinate table with respective drives for moving the object 6 in a well defined manner for these orthogonal coordinates x, y, z.

This relative movement between the ion beam 3 on the one hand and the object 6 on the other hand can additionally or alternatively be used, for example, by scanning the ion beam 3 through at least one and in particular two scanning coils. It can also be realized by a scanning scheme.

The xy extension of the beam interaction region 10, that is, the diameter of the focal point of the ions in the objective field 4 may be less than 1 nm, in particular less than 0.5 nm.

The beam current may be less than 20 pA or less than 9 pA. These small beam currents offer the possibility of very high spatial resolution for detailed review.

5 and 6 enlarged the anvil-like structure of the object 6 before the milling step (Fig. 5), that is, before the interaction of the ion beam 3 and the object 6, and after this milling step (Fig. 6). Is shown in spatial resolution.

In FIG. 6 milling is shown in three linear subregions “1”, “2” and “3” with a longitudinal size of approximately 3 μm and a lateral size of approximately 200 nm.

Fig. 7 again shows the milled subregions "1", "2" and "3" of Fig. 6, which are now highlighted.

8 to 10 show the verification volume candidates, i.e. during detailed review of the subregions "1", "2" and "3" identified in the rough review step, i.e. during the electron microscope imaging of FIG. 5, of the inspection system 1 The counting rates of ion energies corresponding to the elements selenium (Se), tellurium (Te), and antimony (Sb) measured by the secondary electron detection unit 12 are shown in a diagram similar to FIG. 4.

8 shows a time-resolved coefficient rate for sub-region "1". These CPS results show a relatively high selenium ratio with a low ratio close to the resolution limit of tellurium antimony.

Figure 9 shows the results of subregion "2" with a low proportion of all three elements of selenium, tellurium and antimony. The selenium contribution in the CPS measurement according to FIG. 9 begins to occur at a longer milling time with the ion beam 3 indicating that in subregion "2" the selenium is not present directly at the surface but below the surface.

10 shows the time-resolved coefficient rate measured in sub-region "3". Selenium and tellurium exist near the resolution limit. Antimony traces may not be found in subregion "3".

In particular, the inspection method as described above with respect to FIGS. 3 to 10 may be performed in-line during the production of the semiconductor structure of the object 6. Examples of projection lithographic exposure methods for producing micrometer or nanometer scale semiconductor structures are provided in DE 10 2016 201 317 A1 and DE 10 2017 210 162 A1 and the references cited therein. After the edging step, each three-dimensional structure created in the objective field 4 of the projection exposure apparatus appears, which can then be examined in-line (in-situ) via the above-described inspection system 1. Production errors, in particular system production errors, can then be detected during the manufacturing process. Thus, countermeasures are possible to reduce such manufacturing errors during the production process itself and thus reduce waste.

Claims (14)

It is an inspection system (1) for verifying a semiconductor structure,
-Having an ion beam source (2) for spatial decomposition exposure of the structure to be verified with an ion beam (3),
-Having a secondary ion detection device 12,
-The secondary ion detection device 12 comprises a mass spectrometer 13,
-The mass spectrometer 13 is an inspection system capable of simultaneously measuring the ion mass to charge ratio in a given bandwidth. The inspection system according to claim 1, wherein the mass spectrometer (13) is capable of continuously measuring the ion mass to charge ratio in a given bandwidth. 3. Inspection system according to claim 1 or 2, wherein the secondary ion detection device (12) comprises a secondary electron detection unit (19). 4. Inspection system according to any of the preceding claims, wherein the ion beam source (2) produces a rare gas ion beam (3). 5. Inspection system according to claim 4, wherein the ion beam source (2) produces a neon ion beam. The method according to any one of claims 1 to 5, wherein the secondary ion detection device (12) is
-A first delivery position at which the delivery unit 20 delivers secondary ions 7 and 9 emerging from the target volume of the probe structure to be verified to the secondary ion detection unit 19,
-An inspection system comprising a secondary ion transfer unit (20) movable between the second neutral positions. 8. Inspection system according to any one of claims 3 to 7, wherein the secondary ion detection unit (19) comprises a total ion counter. 9. Inspection system according to any one of the preceding claims, wherein the secondary ion detection unit (19) comprises an extended detector array for mass filtered signals. It is an inspection method to verify the semiconductor structure,
-The step of reviewing the outline of the structure to be verified,
-As a detailed review stage of the candidate verification volume identified in the outline review stage,
- Spatial resolved ion beam sputtering within the volume to be reviewed in detail,
- detection of secondary ions (7, 9) from the volume to be examined in detail,
- performed by performing continuous mass spectrometry of the detected secondary ions,
- Continuous mass spectroscopy, including a detailed review step, performed simultaneously within the ion mass to charge ratio bandwidth. The inspection method according to claim 9, wherein the lateral spatial resolution during detailed examination is 100 nm or more. 11. The method of claim 9 or 10, wherein the ion beam is focused on the volume to be examined in detail with a focal diameter less than 5 nm. The inspection method according to any one of claims 9 to 11, wherein the inspection is performed in-line during semiconductor production. 13. The inspection method according to any one of claims 9 to 12, wherein at least one volume to be examined in detail is selected via secondary electron microscopy images. 14. The inspection method according to any one of claims 9 to 13, wherein the material distribution revealed from continuous mass spectroscopy of the detected secondary ions is imaged through a secondary electron microscope.

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