JP6783157B2 - Radiation analyzer - Google Patents

Description

The present invention relates to a radiation analyzer.

Particle analysis can be performed with an analyzer such as a scanning electron microscope (SEM) equipped with an energy dispersive X-ray detector (EDS) or an electron probe microanalyzer (EPMA). For example, in Patent Document 1, particle analysis is performed by obtaining the shape of particles from an electron microscope image, obtaining the composition of particles by elemental analysis, and performing statistics from these results.

JP 2015-148499

FIG. 7 is a flowchart showing an example of the flow of particle analysis in an electron microscope equipped with an energy dispersive X-ray detector.

First, an electron microscope image of the field of view to be analyzed for particles is acquired (step S10).

Next, image processing is performed on the acquired electron microscope image to extract a portion of the particles (step S12).

Next, the size of each extracted particle is calculated. In addition, the position coordinates of each extracted particle are specified (step S14).

Next, each particle is irradiated with an electron beam based on the information of the position coordinates of the particles, the generated characteristic X-ray is detected, and the X-ray energy data of each particle is acquired. Then, spectrum analysis (spectral generation, quantitative analysis, qualitative analysis, etc.) is performed from the acquired X-ray energy data of each particle (step S16).

Particle analysis can be performed by the above steps. After performing the above steps (steps S10 to S16), the sample stage may be moved to perform the above series of steps from another field of view.

FIG. 8 is a sequence diagram showing an example (reference example) of particle analysis in an electron microscope equipped with an energy dispersive X-ray detector. It is assumed that the electron microscope includes an electron microscope main body, an analysis system that controls the electron microscope main body to analyze data, and a detector system that controls a detector.

First, the analysis system sends the position coordinate information of the first particle and the electron probe movement command to the electron microscope.

The electron microscope main body identifies the measurement position based on the position coordinate information, and moves the electron probe to the coordinates of the specified measurement position based on the electron probe movement command. Then, the electron microscope main body sends a movement completion notification to the analysis system.

Upon receiving the movement completion notification, the analysis system sends information on the particle measurement conditions (measurement time) and a spectrum acquisition start command to the detector system.

The detector system collects the spectrum (collects X-ray energy data) for a set measurement time based on the spectrum acquisition start command, and outputs the obtained X-ray energy data. This X-ray energy data is stored in a storage device.

The analysis system periodically checks the detector system to see if spectrum collection is complete (acquisition of status). After confirming that the spectrum collection is completed (that is, the measurement time has passed), the analysis system acquires the X-ray energy data stored in the storage device and analyzes the spectrum of the first particle (spectrum generation, Quantitative analysis, qualitative analysis, etc.).

When the spectrum analysis is completed, the analysis system performs a series of processes on the second particle in the same manner. This series of processing is repeated for the number of particles to be measured.

The particle analysis shown in FIG. 8 has a problem that the particle analysis takes a long time. For example, in the particle analysis shown in FIG. 8, the analysis system does not send the position coordinate information of the next particle and the probe movement command to the detector system until the spectral analysis of one particle is completed. That is, the measurement of the next particle is not performed until the spectral analysis of one particle is completed.

The present invention has been made in view of the above problems, and one of the objects according to some aspects of the present invention is to measure a plurality of measurement positions and analyze the measurement results in a short time. The purpose is to provide a radiation analyzer capable of providing a radiation analyzer.

(1) The radiation analyzer according to the present invention is
A radiation analyzer that moves electron probes to a plurality of measurement positions on a sample, irradiates the measurement positions with the electron probes for a set measurement time, detects the radiation generated, and performs analysis.
A detector that detects the radiation generated from the sample and outputs a signal according to the energy of the radiation.
A signal processing unit that receives signals from the detector and sequentially generates radiation energy data based on the signals.
By sequentially accepting the radiation energy data and adding a measurement delimiter flag at a timing based on the measurement time, a data string in which the radiation energy data and the measurement delimiter flag are arranged in time series is generated, and the data is generated. A data string generator that writes columns to the data string storage section,
A data analysis unit that reads out the data string stored in the data string storage unit and analyzes each measurement position.
An optical system for controlling the electron probe and
An optical system control unit that controls the optical system,
Only including,
The optical system control unit
A process of moving the electron probe to the first measurement position among the plurality of measurement positions and stopping the electron probe for the measurement time.
A process of moving the electron probe to the second measurement position among the plurality of measurement positions and stopping the electron probe for the measurement time.
Is performed continuously .

In such a radiation analyzer, since measurement and analysis can be performed in parallel, measurement of a plurality of measurement positions and analysis of measurement results can be performed in a short time. Further, in such a radiation analyzer, since the measurement at the second measurement position is performed immediately after the measurement at the first measurement position is completed, the measurement at the plurality of measurement positions can be performed in a short time.

(2) In the radiation analyzer according to the present invention
The data string generator may add the measurement delimiter flag at the set interval of the measurement time.

In such a radiation analyzer, it is possible to generate a data string in which the radiation energy data and the measurement delimiter flag are arranged in time series. Radiation energy data for each measurement can be extracted from this data string. Therefore, in such a radiation analyzer, measurement and analysis can be performed in parallel, and measurement of a plurality of measurement positions and analysis of measurement results can be performed in a short time.

(3) In the radiation analyzer according to the present invention
The data string generation unit adds the measurement delimiter flag and the movement delimiter flag at the timing based on the travel time set as the travel time of the electron probe and the measurement time, and adds the radiation energy data and the measurement delimiter flag. The data string in which the movement delimiter flags are arranged in chronological order may be generated.

In such a radiation analyzer, radiation energy data while the electron probe is moving can be excluded from the analysis. Therefore, according to such a radiation analyzer, analysis can be performed with higher accuracy.

(4) In the radiation analyzer according to the present invention
The data string generation unit
The process of adding the measurement delimiter flag at the interval of the sum of the movement time and the measurement time, and
After adding the measurement delimiter flag, the process of adding the movement delimiter flag at the timing when the movement time elapses,
May be done.

In such a radiation analyzer, the radiation energy data while the electron probe is moving can be extracted from the data string, and the radiation energy data while the electron probe is moving can be excluded from the analysis.

(5) In the radiation analyzer according to the present invention
The data analysis unit may take out the radiation energy data delimited by the movement delimiter flag from the data string and exclude it from the analysis.

With such a radiation analyzer, analysis can be performed with higher accuracy.

(6) In the radiation analyzer according to the present invention
An input unit that accepts input of the travel time information may be included.

(7) In the radiation analyzer according to the present invention
The writing of the data string by the data string generation unit and the reading of the data string by the data analysis unit may be performed in parallel.

In such a radiation analyzer, it is possible to measure a plurality of measurement positions and analyze the measurement results in a short time.

(8) In the radiation analyzer according to the present invention
An input unit that accepts input of the measurement time information may be included.

(9) In the radiation analyzer according to the present invention
The optical system control unit may move the electron probe from the first measurement position to the second measurement position while the electron probe is irradiated on the sample.

With such a radiation analyzer, it is possible to measure a plurality of measurement positions in a short time.

(10) The radiation analyzer according to the present invention is
A radiation analyzer that moves electron probes to a plurality of measurement positions on a sample, irradiates the measurement positions with the electron probes for a set measurement time, detects the radiation generated, and performs analysis.
A detector that detects the radiation generated from the sample and outputs a signal according to the energy of the radiation.
A signal processing unit that receives signals from the detector and sequentially generates radiation energy data based on the signals.
By sequentially accepting the radiation energy data and adding a measurement delimiter flag at a timing based on the measurement time, a data string in which the radiation energy data and the measurement delimiter flag are arranged in time series is generated, and the data is generated. A data string generator that writes columns to the data string storage section,
A data analysis unit that reads out the data string stored in the data string storage unit and analyzes each measurement position.
Including
The data string generation unit adds the measurement delimiter flag and the movement delimiter flag at the timing based on the travel time set as the travel time of the electron probe and the measurement time, and adds the radiation energy data and the measurement delimiter flag. Generates the data string in which the movement delimiter flags are arranged in chronological order.
The data string generation unit
The process of adding the measurement delimiter flag at the interval of the sum of the movement time and the measurement time, and
After adding the measurement delimiter flag, the process of adding the movement delimiter flag at the timing when the movement time elapses,
To do .

(11) The radiation analyzer according to the present invention is
A radiation analyzer that moves electron probes to a plurality of measurement positions on a sample, irradiates the measurement positions with the electron probes for a set measurement time, detects the radiation generated, and performs analysis.
A detector that detects the radiation generated from the sample and outputs a signal according to the energy of the radiation.
A signal processing unit that receives signals from the detector and sequentially generates radiation energy data based on the signals.
By sequentially accepting the radiation energy data and adding a measurement delimiter flag at a timing based on the measurement time, a data string in which the radiation energy data and the measurement delimiter flag are arranged in time series is generated, and the data is generated. A data string generator that writes columns to the data string storage section,
A data analysis unit that reads out the data string stored in the data string storage unit and analyzes each measurement position.
Including
The writing of the data string by the data string generation unit and the reading of the data string by the data analysis unit are performed in parallel .

The figure which shows typically the structure of the electron microscope which concerns on this embodiment. The figure for demonstrating the structure of the data string stored in the data string storage part. The flowchart which shows an example of the flow of particle analysis in the electron microscope which concerns on this embodiment. The sequence diagram which shows an example of the particle analysis in the electron microscope which concerns on this embodiment. The figure for demonstrating the modification of the structure of the data string stored in the data string storage part. The figure for demonstrating the modification of the structure of the data string stored in the data string storage part. The flowchart which shows an example of the flow of particle analysis in the electron microscope equipped with the energy dispersive X-ray detector. A sequence diagram showing an example (reference example) of particle analysis in an electron microscope equipped with an energy dispersive X-ray detector.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the embodiments described below do not unreasonably limit the contents of the present invention described in the claims. Moreover, not all of the configurations described below are essential constituent requirements of the present invention.

Further, in the following, as the radiation analyzer according to the present invention, an electron microscope equipped with an energy dispersive X-ray detector will be described as an example, but the radiation analyzer according to the present invention is not limited thereto. The radiation device according to the present invention may be an electron probe microanalyzer. Further, the radiation device according to the present invention may be a device that detects and analyzes radiation other than X-rays (γ-rays and the like).

1. 1. Analytical device First, the electron microscope 100 according to the present embodiment will be described with reference to the drawings. FIG. 1 is a diagram schematically showing a configuration of an electron microscope 100 according to the present embodiment.

The electron microscope 100 is equipped with an EDS detector (energy dispersive X-ray detector) 9. In the electron microscope 100, the electrons generated in the electron source 2 are focused by the focusing lens 3 and the objective lens 4 to form an electron probe, and the electrons are emitted from the irradiation point of the electron probe when the surface of the sample S is scanned by the electron probe. Secondary electrons can be detected and imaged. Also,
The electron microscope 100 can obtain a spectrum by detecting characteristic X-rays generated when the sample S is irradiated with an electron probe.

Further, the electron microscope 100 can move the electron probe to a plurality of measurement positions on the sample S, irradiate the measurement position with the electron probe for a set measurement time, and detect and analyze X-rays generated. it can. Specifically, the electron microscope 100 can perform particle analysis. In particle analysis, particles on the surface of sample S are extracted from an electron microscope image according to a defined rule, particle shape information such as the size of individual particles is calculated, and these particles are obtained by irradiating them with an electron probe. Information such as the composition of particles is acquired by detecting X-rays.

The electron microscope 100 includes an electron microscope main body 1, an electron microscope main body control device 10, a detector control device 20, an operation unit 30, a display unit 40, a storage unit 50, a data string storage unit 52, and a processing unit. 60 and.

The electron microscope main body 1 includes an electron source 2, a focusing lens 3, an objective lens 4, a deflector 5, a sample stage 7, a secondary electron detector 8, and an EDS detector 9. ing.

The electron source 2 generates electrons. The electron source 2 is, for example, an electron gun that accelerates electrons emitted from a cathode by an anode and emits an electron beam.

The focusing lens 3 is a lens for forming an electron probe by focusing the electron beams emitted from the electron source 2. The focusing lens 3 can control the diameter of the electron probe and the probe current (irradiation current amount).

The objective lens 4 is a lens for forming an electron probe arranged immediately before the sample S. The objective lens 4 includes, for example, a coil and a yoke. In the objective lens 4, the lines of magnetic force formed by the coil are confined in a yoke made of a material having high magnetic permeability such as iron, and a notch (lens gap) is formed in a part of the yoke to distribute the magnetic force lines at high density. Leaks magnetic field lines on the optical axis.

The deflector 5 is arranged between the focusing lens 3 and the objective lens 4. The deflector 5 deflects an electron probe (electron beam) formed by the focusing lens 3 and the objective lens 4. The deflector 5 is used to scan the electron probe on the sample S. The deflector 5 is also used to move the electron probe to an arbitrary position of the sample S and irradiate the position with the electron probe. The deflector 5 functions as an optical system for controlling the electron probe.

In the illustrated example, the deflector 5 has two stages, but it may have one stage or three or more stages. Further, here, the deflector 5 is used for two purposes (scanning of the electron probe and irradiation of an arbitrary position of the electron probe), and the deflector used for scanning the electron probe and the electron probe on the sample S. A deflector used to irradiate any position of the above may be provided.

Sample S is placed on the sample stage 7. The sample stage 7 can support the sample S and move the sample S. The sample stage 7 has a drive mechanism for moving the sample S.

The secondary electron detector 8 is a detector for detecting the secondary electrons emitted from the sample S by being irradiated with the electron probe. The output signal of the secondary electron detector 8 is stored in the storage unit 50 in synchronization with the scanning signal of the electron beam. Thereby, an electron microscope image (secondary electron image) can be obtained.

The EDS detector 9 detects characteristic X-rays generated from the sample S by irradiating the sample S with an electron probe. The EDS detector 9 is a detector for discriminating X-rays by energy and obtaining a spectrum. The EDS detector 9 outputs a signal corresponding to the energy of the incident X-ray.

The electron microscope main body control device 10 controls each part (excluding the EDS detector 9) of the electron microscope main body 1. The electron microscope main body control device 10 supplies an exciting current to the focusing lens 3 and the objective lens 4 and controls the driving mechanism of the sample stage 7 based on the control signal from the processing unit 60, for example. Further, the electron microscope main body control device 10 sends a scanning signal to the deflector 5 based on the control signal from the processing unit 60. As a result, the electron probe is scanned on the sample S.

The detector control device 20 controls the EDS detector 9. The detector control device 20 controls the EDS detector 9 based on the control signal from the processing unit 60 (detector control unit 64). The detector control device 20 operates the deflector 5 so that the electron probe moves to the measurement position set based on the control signal.

The deflector 5 may be controlled by the electron microscope main body control device 10 (electron microscope main body control unit 62) or may be controlled by the detector control device 20 (detector control unit 64).

Further, the detector control device 20 functions as a signal processing unit that receives a signal from the EDS detector 9 and generates X-ray energy data (an example of radiation energy data) based on the signal. The detector control device 20 receives the output signal of the EDS detector 9 (a signal corresponding to the X-ray energy detected by the EDS detector 9), and sequentially generates X-ray energy data based on the signal. .. The X-ray energy data has information on the energy of the X-rays incident on the EDS detector 9.

For example, the detector control device 20 generates a pulse signal having a height corresponding to the detected X-ray energy from the output signal of the EDS detector 9, and acquires information on the peak value of the pulse signal. The X-ray energy data is the data of this peak value.

The detector control device 20 outputs measurement position data including measurement position information. The detector control device 20 outputs the measurement position data and the X-ray energy data to the processing unit 60.

The operation unit 30 (an example of an input unit) acquires an operation signal corresponding to an operation by the user and sends the operation signal to the processing unit 60. The function of the operation unit 30 can be realized by, for example, buttons, keys, a touch panel display, a microphone, and the like.

The display unit 40 displays an image generated by the processing unit 60, and its function can be realized by an LCD, a CRT, or the like.

The storage unit 50 stores programs, data, and the like for the processing unit 60 to perform various calculation processes. The storage unit 50 is also used as a work area of the processing unit 60, and is also used to temporarily store the calculation results and the like executed by the processing unit 60 according to various programs. The function of the storage unit 50 can be realized by a hard disk, RAM, or the like.

For example, an electron microscope image (SEM image) is stored in the storage unit 50.

The data string storage unit 52 stores a data string described later. The function of the data string storage unit 52 can be realized by, for example, a dual port memory capable of simultaneously (or almost simultaneously) performing a plurality of reads and writes.

The processing unit 60 performs processing for performing particle analysis described later. Further, the processing unit 60 performs various processing according to the operation signal from the operation unit 30, processing for displaying various information on the display unit 40, and the like. The function of the processing unit 60 can be realized by executing a program on various processors (CPU, DSP, etc.). At least a part of the function of the processing unit 60 may be realized by a dedicated circuit such as an ASIC (gate array or the like). The processing unit 60 includes an electron microscope main body control unit 62, a detector control unit 64 (an example of an optical system control unit), a data sequence generation unit 66, and a data analysis unit 68.

The electron microscope main body control unit 62 generates a control signal for controlling each part of the electron microscope main body 1 and sends the control signal to the electron microscope main body control device 10.

The detector control unit 64 generates a control signal for controlling the EDS detector 9 and sends the control signal to the detector control device 20.

The data string generation unit 66 sequentially receives the X-ray energy data and the measurement position data output from the detector control device 20, adds the measurement delimiter flag at the timing based on the set measurement time, and adds the X-ray energy. A data string in which the data, the measurement position data, and the measurement delimiter flag are arranged in chronological order is generated (see FIG. 2). The data string generation unit 66 adds a measurement delimiter flag, for example, at a set measurement time interval. The measurement time is the time required for one measurement (time for irradiating one measurement position with an electron probe), and can be appropriately set.

The data string generation unit 66 sequentially writes the generated data string to the data string storage unit 52. The structure of the data string stored in the data string storage unit 52 will be described later.

The data analysis unit 68 reads out the data string stored in the data string storage unit 52 and performs spectrum analysis. The data analysis unit 68 uses the data string delimited by the measurement delimiter flag as data for one measurement position, generates a spectrum for each measurement position, and performs qualitative analysis, quantitative analysis, and the like from the generated spectrum.

In addition, the data analysis unit 68 performs a process of extracting particles from an electron microscope image, a process of calculating the size of each extracted particle, a process of specifying the position coordinates of each extracted particle, and the like.

FIG. 2 is a diagram for explaining the configuration of the data string stored in the data string storage unit 52.

The data sequence includes X-ray energy data D, measurement position data P, and measurement delimiter flag M.

As described above, the X-ray energy data D is the data generated by the detector control device 20, and is the data of the energy value of the X-rays incident on the EDS detector 9.

The measurement position data P is data of the coordinates of the measurement position (position coordinates on the sample stage 7). The measurement position data P includes information on the tilt angle of the sample stage 7 (sample S) and information on the rotation angle of the sample stage 7 (sample S) in addition to the position (X coordinate, Y coordinate) on the sample stage 7. It may be included.

The measurement delimiter flag M is a flag for extracting data for one measurement (that is, data at one measurement position). The measurement delimiter flag M is added at a timing based on the set measurement time T. In the present embodiment, the measurement delimiter flags M are added at intervals of the set measurement time T. For example, when the measurement time T is set to 1 second, the measurement delimiter flag M is added at 1 second intervals. The process of adding the measurement delimiter flag M in the data sequence generation unit 66 is started at the same timing as the start of measurement (start of irradiation of the electron probe to the first measurement position).

In this embodiment, the movement time of the electron probe (the time between the movement of the electron probe from the n-1st measurement position to the nth measurement position) is not taken into consideration. That is, the X-ray energy data D while the electron probe is moving is also included in the data string delimited by the measurement delimiter flag M. However, in an electron microscope, the moving time of the electron probe (for example, about several μs) is usually extremely short with respect to the measurement time T (for example, about several tens of milliseconds to several tens of seconds). Therefore, the influence of the X-ray energy data D on the spectrum analysis while the electron probe is moving can be ignored.

The data string may include data of measurement conditions other than the X-ray energy data D and the measurement position data P. Examples of such data include information on elapsed time, information on actual elapsed time (Real Time), and the like. Here, the elapsed time is the time actually elapsed from the start of the measurement, and the actual elapsed time is the actual measurement time excluding the dead time of the EDS.

The data string is data (time series data) in which the X-ray energy data D, the measurement position data P, and the measurement delimiter flag M are arranged in a line along the time axis. The X-ray energy data D, the measurement position data P, and the measurement delimiter flag M may each have time information (information on the coordinates of the time axis).

By extracting the X-ray energy data included in the data string delimited by the measurement delimiter flag M, a spectrum can be generated for each measurement position. Specifically, by counting the number of X-ray energy data D included in the data string delimited by the measurement delimiter flag M for each energy, a spectrum (EDS spectrum) at the measurement position can be generated. .. In addition, the measurement position can be specified from the measurement position data P included in the data string delimited by the measurement delimiter flag M.

2. Particle analysis Next, particle analysis in the electron microscope 100 will be described. In the electron microscope 100, particle analysis is automatically performed. FIG. 3 is a flowchart showing an example of the flow of particle analysis in the electron microscope 100.

The user sets the number of particles to be analyzed and measurement conditions (measurement time, etc.) via the operation unit 30 before giving an instruction to start particle analysis. After setting the number of particles and the measurement conditions, the user gives an instruction to start the particle analysis via the operation unit 30. The operation unit 30 receives input of information on measurement conditions (measurement time) and input of an instruction to start particle analysis.

The processing unit 60 determines whether or not the user has given an instruction to start particle analysis (start instruction) (step S100), and waits until the start instruction is given (NO in step S100). The processing unit 60 determines that the user has given the start instruction when the start instruction is input from the operation unit 30.

When it is determined that the start instruction has been given (YES in step S100), the electron microscope main body control unit 62 acquires an electron microscope image (step S102).

Specifically, the electron microscope main body control unit 62 generates a control signal for acquiring an electron microscope image and sends it to the electron microscope main body control device 10. The electron microscope main body control device 10 operates the electron microscope main body 1 based on the control signal. As a result, the electron microscope image for one field of view is stored in the storage unit 50.

Next, the data analysis unit 68 performs image processing on the acquired electron microscope image to extract a particle portion (step S104).

Next, the data analysis unit 68 calculates the size of each extracted particle. Further, the data analysis unit 68 specifies the position coordinates of each extracted particle (step S106).

Next, the processing unit 60 measures each particle (measurement by the EDS method) to acquire X-ray energy data, and spectrum analysis (spectrum generation, quantitative analysis, etc.) of each particle from the obtained X-ray energy data. Qualitative analysis and the like) are performed (step S108). Details of this process will be described later.

Next, the processing unit 60 determines whether or not the spectrum analysis for the set number of particles has been performed (step S110).

When it is determined that the spectrum analysis for the set number of particles has not been performed (NO in step S110), returning to step S100, the electron microscope main body control unit 62 moves the sample stage 7 to another field of view. (Step S100). Then, the processes of steps S102 to S110 are performed using an electron microscope image of another field of view.

When it is determined that the spectrum analysis for the set number of particles has been performed (YES in step S110), the particles are based on the calculation result of the size of each particle and the result of the spectrum analysis for the set number of particles. Are classified based on the defined rules (step S112). The processing unit 60 controls the display unit 40 to display the classification result of the particles, and ends the processing.

The collection of X-ray energy data and the spectrum analysis (step S108) will be described. FIG. 4 is a sequence diagram showing an example of particle analysis (collection of X-ray energy data and spectrum analysis (step S108)) in the electron microscope 100.

The processing unit 60 (detector control unit 64) includes measurement conditions including information on the measurement time and information on the position coordinates (coordinates of the measurement position) of all the particles extracted from the electron microscope image in the process of step S104. Information is sent to the detector control device 20 to set measurement conditions.

When the measurement conditions are set, the probe movement process, the X-ray energy data collection process, and the spectrum analysis process are performed in parallel. That is, while the EDS measurement for each particle is performed and the X-ray energy data is collected, the spectrum analysis is performed in parallel. Hereinafter, probe movement processing, X-ray energy data collection processing, and probe movement processing will be described.

<Probe movement processing>
When the measurement conditions are set, the detector control unit 64 sends a probe movement command to the electron microscope main body 1 (deflector 5) via the detector control device 20. The electron microscope main body 1 (deflector 5) moves the electron probe to the measurement position (position coordinates of the particles) based on the probe movement command. Then, when the electron probe moves to the measurement position, the electron microscope main body 1 stops the electron probe for a set measurement time.

When the detector control unit 64 determines that the measurement time has elapsed, the detector control unit 64 issues a probe movement command to the electron microscope main body 1 (deflector 5) to move the electron probe to the next measurement position (positional coordinates of the next particle). send. That is, the detector control unit 64 sends a probe movement command to the electron microscope main body 1 at the set measurement time interval. Therefore, in the electron microscope main body 1 (deflector 5), the operation of moving the electron probe to the next measurement position based on the probe movement command and stopping the electron probe for the measurement time is repeatedly performed.

In this way, the detector control unit 64 moves the electron probe to the n-1st measurement position (first measurement position) and stops the electron probe for a set measurement time, and the nth measurement position. The process of moving the electron probe to the (second measurement position) and stopping the electron probe for a set measurement time is continuously performed. That is, the detector control unit 64 immediately moves the electron probe to the nth measurement position after stopping the electron probe for the measurement time set at the n-1st measurement position, and sets the measurement time. Only stop the electron probe. At this time, the detector control unit 64 moves the electron probe from the n-1st measurement position to the nth measurement position while the electron probe is irradiating the sample S. The electron probe is in a state of being irradiated with the sample S (the electron probe is in the ON state) until the set number of particles is measured.

<Collection processing of X-ray energy data>
The detector control device 20 receives the output signal of the EDS detector 9, generates X-ray energy data based on the output signal, and outputs the X-ray energy data to the processing unit 60. The data string generation unit 66 adds a measurement delimiter flag to the X-ray energy data sequentially sent from the detector control device 20 at a timing based on the measurement time, and the X-ray energy data and the measurement delimiter flag are displayed in time series. It is written in the data string storage unit 52 as an arranged data string.

As described above, in the probe movement process, the process of moving the electron probe to the n-1st measurement position and stopping the electron probe for the set measurement time and the process of moving the electron probe to the nth measurement position are set. The process of stopping the electron probe for the measured measurement time is continuously performed. Therefore, the X-ray energy data at the n-1st measurement position and the X-ray energy data at the nth measurement position are also continuous. Since the data string generation unit 66 adds the measurement delimiter flag at the set measurement time interval, the X-ray energy data at the n-1st measurement position and the X-ray energy data at the nth measurement position can be separated. Yes (see Figure 2).

The detector control device 20 continues to output X-ray energy data until the measurement is completed (for example, until it is determined that the analysis of the set number of particles has been performed (YES in step S110)). Therefore, the data string is continuously written in the data string storage unit 52 until the measurement is completed.

As described above, the probe movement process by the detector control unit 64 and the process of adding the measurement delimiter flag by the data sequence generation unit 66 are managed by time. Specifically, the process of moving the electron probe by the detector control unit 64 and the process of adding the measurement delimiter flag by the data string generation unit 66 are both performed at the set measurement time interval. Therefore, the two processes can be performed at the same timing.

<Spectrum analysis>
The data analysis unit 68 reads out the data string stored in the data string storage unit 52 and performs spectrum analysis. The data analysis unit 68 uses the data string delimited by the measurement delimiter flag in the data string as data for one measurement position, generates a spectrum for each measurement position, and performs qualitative analysis and quantitative analysis.

The reading of the data string by the data analysis unit 68 is performed in parallel with the writing of the data string by the data string generation unit 66. When a certain amount of data is written to the data string storage unit 52, the data analysis unit 68 reads out the data string from the data string storage unit 52. The timing of reading the data string from the data string storage unit 52 is not particularly limited. The data analysis unit 68 performs spectrum analysis while the probe movement process and the X-ray energy data collection process are being performed.

The electron microscope 100 has, for example, the following features.

In the electron microscope 100, the detector control device 20 receives the signal from the EDS detector 9 and sequentially generates X-ray energy data, and the data string generation unit 66 adds a measurement delimiter flag at a timing based on the measurement time. A data string in which the X-ray energy data and the measurement delimiter flag are arranged in time series is generated and written in the data string storage unit 52. Therefore, the data analysis unit 68 can take out the X-ray energy data for each measurement by reading the data string stored in the data string storage unit 52. Therefore, in the electron microscope 100, EDS measurement and spectrum analysis can be performed in parallel, and particle analysis can be performed in a short time.

In the electron microscope 100, the data sequence generation unit 66 adds a measurement delimiter flag at a set measurement time interval. Therefore, it is possible to generate a data string in which the X-ray energy data and the measurement delimiter flag are arranged in time series. X-ray energy data for each measurement position can be extracted from this data string. Therefore, in the electron microscope 100, EDS measurement and spectrum analysis can be performed in parallel, and particle analysis can be performed in a short time.

In the electron microscope 100, the data string generation unit 66 writes the data string to the data string storage unit 52 and the data analysis unit 68 reads the data string to the data string storage unit 52 in parallel. Therefore, the electron microscope 100 can perform particle analysis in a short time.

In the electron microscope 100, the detector control unit 64 moves the electron probe to the first measurement position among the plurality of measurement positions and stops the electron probe at the first measurement position for the measurement time, and among the plurality of measurement positions. The process of moving the electron probe to the second measurement position and stopping the electron probe at the second measurement position for the measurement time is continuously performed. That is, in the electron microscope 100, as soon as the measurement at the first measurement position is completed, the measurement at the second measurement position is performed, so that the measurement at the plurality of measurement positions can be performed in a short time.

In the electron microscope 100, the detector control unit 64 moves the electron probe from the first measurement position to the second measurement position while the sample S is irradiated with the electron probe. Therefore, in the electron microscope 100, the measurement of a plurality of measurement positions can be performed in a short time.

Here, the particle analysis in the electron microscope 100 and the particle analysis shown in FIG. 8 are compared.

In the particle analysis shown in FIG. 8, the spectrum analysis could not be performed until the EDS measurement for one particle was completed. That is, no spectral analysis was performed while the EDS measurement was being performed. On the other hand, in the particle analysis of the electron microscope 100, since the EDS measurement and the spectrum analysis can be performed in parallel, the spectrum analysis can be performed even while the EDS measurement is being performed.

Further, in the particle analysis shown in FIG. 8, when the electron probe completes the movement to the measurement position, the movement completion notification is returned to the analysis system. On the other hand, in the particle analysis of the electron microscope 100, as described above, the probe movement process is controlled by time, so that the movement of the electron microscope main body 1 is completed even if the movement of the electron microscope to the measurement position is completed. No need to return notifications. Therefore, in the electron microscope 100, the time required for particle analysis can be shortened.

Further, in the particle analysis shown in FIG. 8, the analysis system sends information on the measurement conditions to the detector system each time one measurement position is measured. On the other hand, in the particle analysis of the electron microscope 100, since the information of the measurement conditions is sent to the detector control device 20 at once before the measurement is started, the time required for the particle analysis can be shortened.

Further, in the particle analysis shown in FIG. 8, the analysis system inquires the detector system of the end of measurement (acquisition of status) at regular time intervals. However, even if the measurement is completed, a delay may occur depending on the timing of the inquiry. On the other hand, in the electron microscope 100, the processing unit 60 does not need to inquire the detector control device 20 about the end of the measurement, and such a delay does not occur. Therefore, in the electron microscope 100, the time required for particle analysis can be shortened.

3. 3. Modifications The present invention is not limited to the above-described embodiment, and various modifications can be carried out within the scope of the gist of the present invention.

3.1. First Modification Example In the above-described embodiment, the data string generation unit 66 adds a measurement delimiter flag at a timing based on the measurement time to generate a data string in which the X-ray energy data and the measurement delimiter flag are arranged in time series. An example of writing to the data string storage unit 52 has been described.

On the other hand, in this modification, the data string generation unit 66 adds the measurement delimiter flag and the movement delimiter flag at the timing based on the movement time and the measurement time set as the time for the electron probe to move, and X-rays. A data string in which the energy data, the measurement partition flag, and the move partition flag are arranged in time series is generated and written in the data string storage unit 52.

Specifically, the data string generation unit 66 adds a measurement delimiter flag at the interval of the sum of the movement time and the measurement time, and a process of adding the movement delimiter flag at the timing when the movement time elapses after adding the measurement delimiter flag. And do.

The travel time is set as a time corresponding to the travel time of the electron probe. The user sets the movement time via the operation unit 30 before giving an instruction to start the particle analysis. The operation unit 30 receives input of travel time information.

The data analysis unit 68 takes out the X-ray energy data delimited by the movement delimiter flag from the data string and excludes it from the analysis.

FIG. 5 is a diagram for explaining the configuration of the data string stored in the data string storage unit 52.

The data string includes X-ray energy data D, measurement position data P, measurement delimiter flag M, and movement delimiter flag N.

The measurement delimiter flag M is added at the interval of the sum of the travel time t and the measurement time T + T. The travel time t is set to, for example, about several μs to several tens of μs. Further, the measurement time T is set to, for example, about several tens of milliseconds to several tens of seconds.

The movement delimiter flag N is a flag for extracting data while the electron probe is moving. The movement delimiter flag N is added at a timing based on the set movement time t and measurement time T. Specifically, the movement delimiter flag N is added at the timing when the movement time t elapses after the measurement delimiter flag M is added. That is, the interval between the movement division flag N and the measurement division flag M is the movement time t. The movement delimiter flag N is added at the interval of the sum t + T of the movement time t and the measurement time T, similarly to the measurement delimiter flag M.

The data string is data (time series data) in which the X-ray energy data D, the measurement position data P, the measurement delimiter flag M, and the movement delimiter flag N are arranged in a line along the time axis.

By extracting the X-ray energy data included in the data string separated by the measurement partition flag M (more specifically, the data string from the measurement partition flag M to the moving partition flag N), the spectrum corresponding to one measurement position. Can be generated. Further, by extracting the X-ray energy data included in the data string delimited by the movement delimiter flag N (more specifically, the data string from the movement delimiter flag N to the measurement delimiter flag M), the extracted data can be electronically displayed. Data while the probe is moving can be excluded from spectral analysis.

According to this modification, it is possible to obtain the same effects as those of the above-described embodiment.

Further, in this modification, the data string generation unit 66 adds the measurement delimiter flag and the movement delimiter flag at the timing based on the movement time set as the time for the electron probe to move and the measurement time to generate the data string. Therefore, the X-ray energy data while the electron probe is moving can be excluded from the spectrum analysis. Therefore, according to this modification, particle analysis can be performed more accurately. In particular, it is effective for particle analysis that requires high quantification accuracy, and for particle analysis using a device that has a long electron probe movement time.

Further, in this modification, the data string generation unit 66 adds a measurement delimiter flag at the interval of the sum of the movement time and the measurement time, and after adding the measurement delimiter flag, sets the movement delimiter flag at the timing when the movement time elapses. Perform the process of adding and. Therefore, according to this modification, the X-ray energy data while the electron probe is moving can be extracted from the data string and excluded from the analysis.

3.2. Second Modified Example In the above-described embodiment, the measurement time T at each measurement position is the same as shown in FIG. 2, but the measurement time T at each measurement position is different as shown in FIG. You may be. For example, the measurement time at the n-2nd measurement position is T1, the measurement time at the n-1st measurement position is T2, the measurement time at the nth measurement position is T3, and the measurement time at the n + 1th measurement position is T3. When the time is set to T4, the data string generation unit 66 measures after the measurement time T1 elapses, the measurement time T1 + T2 elapses, and the measurement time T1 + T2 + T3 elapses after adding the delimiter flag of the n-3rd measurement position. After the lapse of time T1 + T2 + T3 + T4, the measurement delimiter flag is added respectively.

According to this modification, it is possible to obtain the same effects as those of the above-described embodiment.

3.3. Third Modified Example In the above-described embodiment, the case where the electron microscope 100 performs particle analysis has been described, but the present invention can be applied to an analysis method in which measurement of a plurality of measurement positions and analysis of measurement results are performed. Such analysis includes, for example, surface analysis (element mapping, quantitative mapping) in which an electron probe is scanned to detect X-rays from each point and image the distribution of elements, and a plurality of measurement positions are automatically determined. A point analysis that measures and analyzes the measurement result can be mentioned.

Further, in the above-described embodiment, an example in which the electron microscope 100 is equipped with an energy dispersive X-ray detector (EDS detector 9) has been described, but the electron microscope 100 is equipped with, for example, a wavelength dispersive X-ray detector. It may be equipped with both an energy dispersive X-ray detector and a wavelength dispersive X-ray spectroscope.

3.4. Fourth Modification Example In the above-described embodiment, the processing unit 60 includes the data string generation unit 66, but the detector control device 20 may be configured to include the data string generation unit 66. That is, the detector control device 20 may have a function as a signal processing unit and a function as a data string generation unit. In this case, the detector control device 20 receives the signal from the EDS detector 9, sequentially generates X-ray energy data based on the signal, and adds the measurement delimiter flag at the timing based on the measurement time to obtain a data string. Is generated and written to the data string storage unit 52.

It should be noted that the above-described embodiments and modifications are merely examples, and the present invention is not limited thereto. For example, each embodiment and each modification can be combined as appropriate.

The present invention includes substantially the same configurations as those described in the embodiments (eg, configurations with the same function, method and result, or configurations with the same purpose and effect). The present invention also includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. The present invention also includes a configuration that exhibits the same effects as the configuration described in the embodiment or a configuration that can achieve the same object. The present invention also includes a configuration in which a known technique is added to the configuration described in the embodiment.

1 ... electron microscope body, 2 ... electron source, 3 ... focusing lens, 4 ... objective lens, 5 ... deflector, 7 ... sample stage, 8 ... secondary electron detector, 9 ... EDS detector, 10 ... electron microscope body Control device, 20 ... Detector control device, 30 ... Operation unit, 40 ... Display unit, 50 ... Storage unit, 52 ... Data string storage unit, 60 ... Processing unit, 62 ... Electron microscope main body control unit, 64 ... Detector control Unit, 66 ... Data sequence generation unit, 68 ... Data analysis unit, 100 ... Electron microscope

Claims (11)

A radiation analyzer that moves electron probes to a plurality of measurement positions on a sample, irradiates the measurement positions with the electron probes for a set measurement time, detects the radiation generated, and performs analysis.
A detector that detects the radiation generated from the sample and outputs a signal according to the energy of the radiation.
A signal processing unit that receives signals from the detector and sequentially generates radiation energy data based on the signals.
By sequentially accepting the radiation energy data and adding a measurement delimiter flag at a timing based on the measurement time, a data string in which the radiation energy data and the measurement delimiter flag are arranged in time series is generated, and the data is generated. A data string generator that writes columns to the data string storage section,
A data analysis unit that reads out the data string stored in the data string storage unit and analyzes each measurement position.
An optical system for controlling the electron probe and
An optical system control unit that controls the optical system,
Only including,
The optical system control unit
A process of moving the electron probe to the first measurement position among the plurality of measurement positions and stopping the electron probe for the measurement time.
A process of moving the electron probe to the second measurement position among the plurality of measurement positions and stopping the electron probe for the measurement time.
Radiation analyzer that continuously performs . In claim 1,
The data string generation unit is a radiation analyzer that adds the measurement delimiter flag at the set interval of the measurement time. In claim 1,
The data string generation unit adds the measurement delimiter flag and the movement delimiter flag at the timing based on the travel time set as the travel time of the electron probe and the measurement time, and adds the radiation energy data and the measurement delimiter flag. A radiation analyzer that generates the data sequence in which the moving delimiter flags are arranged in chronological order. In claim 3,
The data string generation unit
The process of adding the measurement delimiter flag at the interval of the sum of the movement time and the measurement time, and
After adding the measurement delimiter flag, the process of adding the movement delimiter flag at the timing when the movement time elapses,
Radiation analyzer. In claim 4,
The data analysis unit is a radiation analyzer that extracts the radiation energy data separated by the movement delimiter flag from the data string and excludes it from the analysis. In any one of claims 3 to 5,
A radiation analyzer including an input unit that accepts input of travel time information. In any one of claims 1 to 6,
A radiation analyzer in which writing of the data string by the data string generation unit and reading of the data string by the data analysis unit are performed in parallel. In any one of claims 1 to 7,
A radiation analyzer including an input unit that receives input of the measurement time information. In any one of claims 1 to 8 ,
The optical system control unit is a radiation analyzer that moves the electron probe from the first measurement position to the second measurement position while the sample is irradiated with the electron probe. A radiation analyzer that moves electron probes to a plurality of measurement positions on a sample, irradiates the measurement positions with the electron probes for a set measurement time, detects the radiation generated, and performs analysis.
A detector that detects the radiation generated from the sample and outputs a signal according to the energy of the radiation.
A signal processing unit that receives signals from the detector and sequentially generates radiation energy data based on the signals.
By sequentially accepting the radiation energy data and adding a measurement delimiter flag at a timing based on the measurement time, a data string in which the radiation energy data and the measurement delimiter flag are arranged in time series is generated, and the data is generated. A data string generator that writes columns to the data string storage section,
A data analysis unit that reads out the data string stored in the data string storage unit and analyzes each measurement position.
Only including,
The data string generation unit adds the measurement delimiter flag and the movement delimiter flag at the timing based on the travel time set as the travel time of the electron probe and the measurement time, and adds the radiation energy data and the measurement delimiter flag. Generates the data string in which the movement delimiter flags are arranged in chronological order.
The data string generation unit
The process of adding the measurement delimiter flag at the interval of the sum of the movement time and the measurement time, and
After adding the measurement delimiter flag, the process of adding the movement delimiter flag at the timing when the movement time elapses,
Perform, radiation analyzer. A radiation analyzer that moves electron probes to a plurality of measurement positions on a sample, irradiates the measurement positions with the electron probes for a set measurement time, detects the radiation generated, and performs analysis.
A detector that detects the radiation generated from the sample and outputs a signal according to the energy of the radiation.
A signal processing unit that receives signals from the detector and sequentially generates radiation energy data based on the signals.
By sequentially accepting the radiation energy data and adding a measurement delimiter flag at a timing based on the measurement time, a data string in which the radiation energy data and the measurement delimiter flag are arranged in time series is generated, and the data is generated. A data string generator that writes columns to the data string storage section,
A data analysis unit that reads out the data string stored in the data string storage unit and analyzes each measurement position.
Only including,
A radiation analyzer in which writing of the data string by the data string generation unit and reading of the data string by the data analysis unit are performed in parallel .

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