JP2000324400A - Electron beam imaging device and electron microscope - Google Patents

Abstract

(57) [Summary] [Problem] To capture a high-quality still image and observe a moving image at a high frame rate by using one electron beam imaging apparatus. SOLUTION: A full frame transfer type CCD element 109 is provided, and under the control of a CCD control unit 110, an image is captured by a full frame transfer method when capturing a still image, and a continuous image is captured by a frame transfer method when capturing a moving image. Do. When the full-frame transfer CCD element 109 is operated by the frame transfer method, a part of the electron beam irradiated to the scintillator 107 is blocked by the electron beam blocking plate 112 and a part of the full-frame transfer CCD element 109 is shielded from light. Create an area and use it as a memory.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electron microscope such as a transmission electron microscope image used in a semiconductor device manufacturing field, a new material development research field, a medical biology research field, and the like, and an electron beam provided in the electron microscope. The present invention relates to an electron beam image capturing device for capturing an image.

[0002]

2. Description of the Related Art In a field using a transmission electron microscope, an image pickup device incorporating a CCD element is used as a means for observing and recording an electron beam image. An advantage of using a CCD imaging device is that an image can be recorded as electronic information. In particular, full-frame transfer CCDs are widely used as detectors for capturing beautiful images and measuring electron beams with high accuracy and two-dimensional positional resolution because they can reduce readout noise.

[0003]

In a full frame transfer type CCD, it is necessary to use a shutter or the like to make a time during which light does not hit the CCD (read time).
Therefore, when observing a moving image, searching for a visual field, adjusting an electron microscope, etc., a readout time is required for each frame in addition to the exposure time, so that an image cannot be output at a high frame rate, and the frame rate should be increased. In this case, it is impossible to increase the exposure time, so that there is a disadvantage that the sensitivity is lowered. In addition, when another image pickup means such as a TV camera is used for moving image observation, a difference in appearance caused by a difference in an image pickup device is large, and a quick transition from observation to image pickup is difficult.

[0004] It is an object of the present invention to provide an electron beam imaging apparatus which enables both high-accuracy reading and high-speed reading with one unit. The present invention is also capable of capturing images at high speed to quickly perform moving image observation or visual field search, focusing, astigmatism correction, etc., and also facilitates capturing of high-quality recorded still images. It is an object of the present invention to provide an electron microscope capable of performing the above.

[0005]

According to the present invention, an enlarged image of an electron beam transmitted through a sample is formed on a scintillator and converted into a light image, and the light image is converted to a full frame transfer CCD.
(Hereinafter, referred to as FFT-CCD). The FFT-CCD is read out by a normal full frame transfer method when capturing a captured image with high definition, and the FFT-CCD is operated as a frame transfer CCD (hereinafter referred to as FT-CCD) when reading out at a high frame rate. Read by transfer method. Switching between these two operation modes is performed by a CCD control circuit.

The CCD is operated as an FFT-CCD,
When capturing an electron beam image as a still image, a shutter is used to block the electron beam emitted to the scintillator superimposed on the CCD to create a time during which light does not hit the CCD, and a full frame within that time Captures image signals by transfer method. Further, when the CCD is operated as an FT-CCD and an electron beam image is captured as a moving image, a part of the imaging area of the CCD, for example, a half, is shielded by an electron beam, and a light-shielding portion is formed so that light from the scintillator does not hit.
The light-shielding portion is used as a memory portion for transferring the signal charges from the light-receiving portion when reading is performed by the frame transfer method, whereby the reading can be continuously repeated.

That is, an electron beam image capturing apparatus according to the present invention includes a scintillator for receiving an electron beam image, and a CCD image capturing means for capturing a light image formed on the scintillator as a two-dimensional image. In the device, C
The CD imaging means has a function of using a part of the imaging area as a memory. An electron beam image capturing apparatus according to the present invention is also an electron beam image capturing apparatus that includes a scintillator that receives an electron beam image, and a CCD image capturing unit that captures a light image formed on the scintillator as a two-dimensional image. The CCD imaging means includes a full frame transfer CCD, and a full frame transfer CCD.
A mode in which the entire imaging area of the CD is used as a light receiving unit,
A mode in which the imaging area is divided into a light receiving section and a memory section for use.

In using a part of the CCD image pickup area as a memory, a movable electron beam shielding plate is inserted into a part of the optical path of the electron beam to block a part of the electron beam image receiving area of the scintillator. Then, a light-shielding area where light from the scintillator does not shine is formed in a part of the imaging area of the CCD, and the light-shielding area functions as a memory unit by the CCD control unit.
The memory unit is used for temporarily storing signal charges photoelectrically converted and stored in the light receiving unit of the CCD until the signal charges are read out.

An electron microscope according to the present invention includes an electron gun, an irradiation lens system for irradiating an electron beam emitted from the electron gun to a sample, and a lens system for forming an electron beam image by electrons transmitted through the sample. And an electron microscope including the above-described electron beam image capturing device for capturing an electron beam image, wherein the electron beam image capturing device changes an electron beam image receiving area between high-precision reading and high-speed reading. It is characterized by. The electron beam image captured by the electron microscope of the present invention may be any electron beam image as long as it has a two-dimensional spread, such as a transmission electron beam image of a sample, an electron beam diffraction image, Includes energy dispersion images of electron beams.

At the time of high-precision reading, the entire imaging area of the CCD imaging means provided in the electron beam image receiving apparatus is used as a light receiving section. Used as a memory. Alternatively, the entire electron beam image receiving area of the electron beam imaging device is used for high-precision reading, and a part of the electron beam receiving region of the electron beam image capturing device is used for high-speed reading with a movable electron beam shielding plate. I do.

At the time of high-speed reading, a half area of the imaging area of the CCD imaging means may be used as a light receiving section, or an area less than half of the imaging area of the CCD imaging means may be used as a light receiving section. CCD used as light receiving unit
The smaller the imaging area of the imaging means, the faster reading is possible. According to the present invention, FFT-CC
When a high-quality still image is captured by a CCD camera incorporating D, the entire area of the CCD element is used, and a normal FFT-CCD element is operated using a shutter or the like. Then, when imaging at a high frame rate, the FFT-CCD
By performing the same operation as the FT-CCD,
It is possible to read out the signal charges of the CCD within the exposure time without receiving light, and it is possible to extend the exposure time at the time of high-speed continuous imaging, improve the sensitivity, and further speed up the continuous imaging.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. Here, an example in which the present invention is applied to imaging of a sample transmission electron beam image by a transmission electron microscope will be described. FIG. 1 is a schematic configuration diagram showing an example of a transmission electron microscope incorporating an electron beam image pickup device according to the present invention. The electron beam generated from the electron gun 101 and accelerated by several hundred kilovolts usually emits light from the irradiation lens system 10.
2 irradiates the sample 103. A part of the electron beam applied to the sample 103 passes through the sample 103. As in the case of light, the amount of transmission of the electron beam varies depending on the thickness of the sample 103 and the properties of the sample constituent materials. If there is means for detecting the electron beam transmitted through the sample 103 with two-dimensional positional resolution, this can be captured as a transmitted electron beam image of the sample. What plays this role is the fluorescent plate 106 and the electron beam image pickup device 200. The transmitted electron beam image of the material can be enlarged using the objective lens system 104 and the imaging lens system 105. Since an electron beam forms an image, most of these lenses are electromagnetic lenses that use the action of a magnetic field created by an electromagnet, but may be electrostatic lenses that use the action of an electric field.

Since a transmission electron microscope uses a highly accelerated electron beam, it is possible to obtain a transmission image of a sample enlarged to a magnification which is almost impossible to realize by using an optical microscope. An electron beam blocking means 115a (or 115b) for blocking the electron beam is arranged in the optical path of the electron beam. The electron beam blocking means 115a is of a type for deflecting and blocking an electron beam, and the electron beam blocking means 115b is of a type for mechanically blocking an electron beam.

The electron beam image pickup device 200 includes a scintillator 107 which emits light when irradiated with an electron beam, an FFT-CCD 109 for taking in a two-dimensional light image formed on the scintillator 107 by the electron beam, and a CCD controller 110 for controlling the same. , Computer 111 for displaying and storing the captured image, scintillator 107 and FFT-CCD 1
09 and a fiber optics plate 108 for optically coupling the optical fiber with the optical fiber. Further, an electron beam shielding plate 112 is arranged to be able to advance and retreat so as to cross the optical path of the sample transmission electron beam. There are various CCD reading methods, and the CCD reading methods used here are a full frame transfer method and a frame transfer method.

FIG. 2 is a schematic plan view of the CCD 109 when operating in the FFT-CCD mode. The full frame transfer method will be briefly described with reference to FIG. F
Each pixel of the light receiving unit 201 of the FT-CCD 109 generates a charge according to the amount of light when the light is applied. Each square in the figure represents a pixel of the CCD. FFT-CCD
109 is provided with only one signal charge readout unit 202. Further, the light receiving unit 201 transfers the signal charge generated by each CCD pixel of the light receiving unit to a neighboring CC like a bucket brigade.
It can be moved to the D pixel. Arrow 20 in the figure
Reference numerals 5,204 indicate the moving direction of the signal charge.

Once the exposure is completed and the electric charge is accumulated in each CCD pixel of the light receiving section 201, the electron beam blocking means 115a (or 115b) is operated to block the electron beam irradiated to the scintillator 107. If the scintillator 107 is not irradiated with the electron beam, the scintillator 107 does not generate light, so that no new charge is generated in the light receiving unit 201. In the electron beam cutoff state, under the control of the CCD control unit 110 (see FIG. 1) for controlling the operation of the CCD 109, the signal charges of each pixel in the CCD pixel row 203 having the charge readout unit 202 are transferred to the charge readout unit 202. As shown by an arrow 204, the light is sent one pixel at a time in a certain direction, and enters the charge readout unit 202. The signal charge read out from the charge readout unit 202 is converted into digital data by the A / D converter 206, and is stored as image data at the position of the CCD pixel where the charge originated.

After the pixel data of one column has been read, the signal charges of all the CCD pixels of the light receiving section 201 are moved by one column in the direction of the pixel column 203 from which the reading has been completed, as indicated by an arrow 205. Thereafter, the charge readout device 202
In the CCD pixel row 203 with
The image data is read by moving the signal charges of each CCD pixel toward the charge readout unit 202 by one pixel as indicated by an arrow 204. By repeating this operation, the light receiving unit 201
After reading out all the signal charges of the pixels of
01, the next exposure can be performed.

While the signal charges stored in the pixels of the light receiving unit 201 are being read, light cannot be applied to the pixels of the light receiving unit 201. This is because, when light is applied, an unnecessary image is superimposed on the image data. Therefore, the reading by the full frame transfer method requires a time during which the light receiving unit 201 is not exposed, and the electron beam blocking unit 115a (or 115b) is required.

FIG. 3 shows C in operation in the FT-CCD mode.
FIG. 2 is a schematic plan view of a CD. The reading of the frame transfer method will be briefly described with reference to FIG. In the frame transfer method, for example, half of the pixels provided in the CCD 109 are used as the light receiving unit 301.
The other half of the CCD 109 is always shielded from light and used as the memory unit 302 having a capacity of one screen. Light receiving section 301
Signal charges, which are image data generated by the respective CCD pixels, are collectively stored in the memory unit 302 during the vertical blanking period.
And then transferred from the memory unit 302 to the charge readout unit 202 one horizontal line at a time. That is, the signal charge accumulated for each pixel of the light receiving unit 301 is shielded by light emitted from the scintillator 107 that has received the electron beam image, as shown by an arrow 304 while maintaining the positional relationship within the vertical blanking period. Is moved to the specified memory unit 302. Immediately after the transfer of the signal charges to the memory section 302, the CCD pixels of the light receiving section 301 start accumulating charges of the next image.

The signal charge transferred to the memory unit 302 is
The signal is sent to the charge readout unit 202 in the same manner as described in the full frame transfer method, and the A / D converter 2
The data is converted into digital data by 06 and stored in the memory of the external computer as image data. During this readout period, only the memory section 302 moves the signal charge, and the charge of the light receiving section 301 is not moved but continues to be accumulated. When all the signal charges in the memory unit 302 have been read, the signal charges serving as the next image data are moved from the light receiving unit 301 to the memory unit 302 at one time. By repeating this operation continuously and displaying an image, a moving image can be acquired at a high sensitivity and at a high frame rate.

In the present invention, the operation of the FFT-CCD 109 is a full frame transfer method when capturing a still image with high accuracy, and a frame transfer method when capturing a moving image. FFT-CCD109 when capturing moving images
In order to capture an image by performing a frame transfer operation, a part of the imaging area of the FFT-CCD 109 is blocked,
An area where the electron beam does not hit the scintillator 107 must be created. For this purpose, as shown in FIG. 1, an electron beam shielding plate 112 provided so as to be able to move forward and backward with respect to the optical path of the transmitted electron beam in front of the scintillator 107 is used.

Referring to FIG. 4, the electron beam shielding plate 112 will be described. The electron beam shielding plate 112 is made of a metal plate and does not transmit an electron beam. When capturing video,
This electron beam shielding plate 112 is connected to the CC of the FFT-CCD 109.
The electron beam is put into the optical path of the electron beam up to a position 403 where the D pixel is hidden about half. By doing so, FFT-CCD
Since an unexposed portion can be halved in 109, the CCD pixels in this portion are temporarily used as a memory portion for storing signal charges, and the signal is read out by a frame transfer method.

At the time of capturing a still image, the electron beam shielding plate 112 is moved to a position 404 where the electron beam shielding plate 112 completely retreats from the imaging area of the FFT-CCD 109. Then, the electron beam is FFT-CC
The entire area of the scintillator 107 on D109 is irradiated,
The T-CCD 109 functions as a light receiving section over the entire imaging area. At the end of the exposure time, the electron beam shielding means 115a
(Or 115b) Alternatively, the electron beam shielding plate 112 is operated to create a period in which the scintillator 107 is not irradiated with the electron beam, and the signal charges are read out by the full frame transfer method.

When it is desired to further increase the frame rate at the time of capturing a moving image, the scintillator 1 is irradiated with an electron beam.
The area of the FFT-CCD 109 on which the light emitted from the light source 07 enters (the light receiving unit 301 in FIG. 3) may be further reduced. For this purpose, the electron beam shielding plate 112 shown in FIG.
The CCD 109 may be moved to a position where the imaging area of the CCD 109 is hidden by half or more, for example, to a position indicated by a broken line 405 in FIG. 4, and the signal charges accumulated in the CCD pixels may be read out by the frame transfer method. The frame transfer operation at this time is to move the signal charges of the entire pixels of the light receiving unit so that the signal charges of the pixel columns of the light receiving unit closest to the charge readout unit are moved to a certain pixel column of the charge readout unit. Reading is performed only for the width of the light receiving section. This reduces the amount of data to be read, so the FFT-CCD 109
The frame rate is faster than the case where half of the imaging area is used as the light receiving section.

An FFT-CC used as a light receiving unit
When the area of D109 is reduced to less than half of the imaging area to increase the frame rate at the time of capturing a moving image, it is not always necessary to cover all the CCD pixels other than the pixel row used as the light receiving unit with the electron beam shielding plate 112. The imaging area may be covered so that a memory area of at least one screen capacity can be secured below. That is, the electron beam shielding plate 112 is positioned so as to cover at least the same number of CCD pixel rows as the CCD pixel rows for accumulating signal charges for electron beam image acquisition, including a certain pixel row of the charge readout unit 202. Is also good. For example, when signal charge accumulation for acquiring an electron beam image is performed by using three CCD pixel rows, the electron beam shielding plate 112 includes at least three CC pixel rows including a CCD pixel row having a charge readout unit.
The memory portion 302 may be formed to cover the D pixel columns. Unnecessary charges accumulated by exposing the CCD pixel row not used as the light receiving section were discarded, and only the signal charges for the three CCD pixel rows for which signal charge accumulation for electron beam image acquisition was performed were blocked. This is because it is sufficient to move to the memory unit 302 and sequentially read out from the charge readout unit 202.

FIG. 5 is a schematic block diagram of the CCD control unit 110 for controlling the FFT-CCD 109. FFT-
The signal from the CCD 109 is supplied to an AMP & CDS circuit 501 and amplified to a required level by an amplifier.
Thereafter, noise is removed by a CDS circuit (correlated double sampling circuit), and is converted into a digital signal by an A / D converter 502. The digitized signal is input to I / F5
The video signal 508 is transferred to the external computer 111 (see FIG. 1) as a video signal 508 via an RS-422 signal. On the other hand, the signal generated from the timing signal generator 505 is supplied to the FFT-CCD via the CCD driver 506.
109 is driven. The CCD control unit 110 further includes a power supply 507 necessary for the operation of these circuits, and the entire operation is controlled by the CPU 504. A camera control signal 509 for controlling the gain and the exposure time of the imaging apparatus is input from the computer 111 to the CPU 504 via the I / F 503.

In order to make the FFT-CCD 109 operate as an FT-CCD, for example, half of the FFT-CCD 109 is functioned as a memory unit independent of the exposure unit, so that half of the effective area of the CCD is shielded. . For this reason,
As described above, the electron beam shielding plate 112 for intercepting the electron beam is inserted into the electron traveling system of the electron microscope, and an FT-type CCD having a memory unit equivalently as a whole using an FFT-CCD.
Construct a CCD. By supplying the insertion of the electron beam shielding plate 112 as an FT control signal 510 from outside, the CCD control unit 110 generates a timing signal for operating the FFT-CCD 109 as an FT-CCD. In the operation of the FT-CCD, after the exposure, the captured electron beam image is transferred to the shielded memory unit at a high speed, and then the reading operation is started. Reading signals from the memory unit
By performing the operation during the next exposure time, although the imaging area is reduced to half, it is possible to perform imaging at a higher frame rate than when reading is performed by a series of operations of exposing the FFT-CCD → intercepting the electron beam → reading.

The method of taking in an image by increasing the frame rate by narrowing the exposure area of the CCD is also effective when trying to analyze the energy of electron beams together. The energy analysis system of the electron microscope is used for separating the electron beam whose energy has been absorbed by the sample, and is also called an energy filter. The trajectory of the electron beam is bent by the magnetic field of an electromagnet arranged so as to sandwich the electron beam, and the energy of the electron beam is separated according to the bending method. Current,
There are various energy analysis systems or energy filters. Here, a γ-type energy filter will be described as an example.

FIG. 6 is an explanatory diagram of an electron beam energy analysis system (γ-type filter). The energy filter 601 generates a magnetic field in a direction perpendicular to the plane of the drawing, and the electron beam entering the beam is bent like a trajectory 602 so as to deviate from the original optical axis and return to the optical axis. At this time, in the energy filter 601, an electron beam with low energy bends greatly, and an electron beam with high energy bends small. For this reason, the electron beam that has passed through the energy filter 601 bends differently depending on the energy and is dispersed like light that has passed through a prism. Energy dispersion occurs in one fixed direction, and an electron beam having the same energy comes in a direction perpendicular to the energy dispersion direction 611. This energy dispersion image is captured using the electron beam image capturing apparatus 200 according to the present invention.

FIG. 7 is an explanatory diagram showing the relationship between the light receiving section 301 and the memory section 302 set in the FFT-CCD 109 provided in the electron beam image pickup apparatus, and the energy dispersion direction 611. As shown in FIG.
CCD1 set when FT-CCD operates 109
The direction of the boundary between the light receiving unit 301 and the memory unit 302 is set to be parallel to the energy dispersion direction 611.
At this time, CCD pixels arranged in a direction 612 orthogonal to the energy dispersion direction detect an electron beam having the same energy. The electron beam having the same energy is collected and the energy distribution of the electron beam transmitted through the sample is examined.
It is not necessary to collect all of the two electron beams, and it is possible to perform more efficient electron beam energy analysis by capturing data faster than that.

In order to capture data quickly, the light receiving section 30
The number of pixels in the direction 612 orthogonal to the energy dispersion direction is reduced by reducing 1. The signal charges accumulated in the pixels of the light receiving unit 301 are moved to the memory unit 302 as indicated by an arrow 614, and unnecessary charges are discarded. And the memory unit 3
At the same time as reading out the charge moved to 02 from the charge readout unit 202, the next exposure to the light receiving unit 301 is started.

FIG. 8 shows the electron beam image pickup device 2 shown in FIG.
9 is a graph showing an example of an electron beam energy analysis result obtained from the output of No. 00. The horizontal axis represents the energy of the electron beam, and the vertical axis represents the number of electron beams having that energy.
This graph shows the data read from the FFT-CCD 109 incorporated in the electron beam imaging apparatus 200 and converted into digital data in a direction 61 orthogonal to the energy dispersion direction.
2 are added together and plotted for each pixel position in the energy dispersion direction 611.

[0033]

According to the present invention, it is possible to obtain an electron beam imaging apparatus capable of selectively performing high-precision reading and high-speed reading with one device. Also, according to the present invention,
It is possible to obtain an electron microscope that can perform operations such as observation and recording more smoothly and with higher quality while viewing the same screen.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of a transmission electron microscope incorporating an electron beam image pickup device according to the present invention.

FIG. 2 is a schematic plan view of the CCD when operating in an FFT-CCD mode.

FIG. 3 is a schematic plan view of the CCD when operating in an FT-CCD mode.

FIG. 4 is an explanatory view of an electron beam shielding plate.

FIG. 5 is a schematic block diagram of a control unit that controls the CCD.

FIG. 6 is an explanatory diagram of an electron beam energy analysis system (γ-type filter).

FIG. 7 is an FFT-C provided in the electron beam imaging apparatus.
FIG. 4 is an explanatory diagram showing a relationship between a light receiving unit and a memory unit set in a CD and an energy dispersion direction.

FIG. 8 is a graph showing an example of an electron beam energy analysis result.

[Explanation of symbols]

101: electron gun, 102: irradiation lens system, 103: sample, 104: objective lens system, 105: imaging lens system, 1
06: fluorescent plate, 107: scintillator, 108: fiber optics plate, 109: FFT-CCD,
110: CCD control unit, 111: Computer, 112
... Electron beam shielding plate, 115a, 115b ... Electron beam shielding means, 200 ... Electron beam image pickup device, 201 ... Light receiving unit, 20
2 ... Charge readout device, 203 ... Pixel column with charge readout device, 204 ... Direction and distance of signal charge transfer in the pixel column with charge readout device during readout operation,
205... Signal charge moving direction and moving distance of a pixel column without a charge readout unit during readout operation, 206... A / D
Converter, 301: light receiving unit, 302: memory unit, 304 ...
The direction and distance of signal charge movement from the light receiving section to the memory section,
403, 405: Electron beam shielding plate position during frame transfer operation, 404: Electron beam shielding plate position during full frame transfer operation, 501: AMP & CDS, 502
... A / D converter, 503 ... I / F, 504 ... CPU, 5
05: Timing signal generator, 506: CCD driver, 507: Power supply, 508: Video signal, 509: Camera control signal, 510: FT control signal, 601: Energy filter, 602: Electron beam bent by magnetic field in the filter Orbit of 611, energy dispersion direction, 61
2: a direction orthogonal to the energy dispersion direction, 614: a moving direction and a moving distance of the signal charge from the light receiving section to the memory section.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor, Adult Sunakosawa, 882, Omo, Oaza, Hitachinaka City, Ibaraki Prefecture Inside the Measurement Department, Hitachi, Ltd. Inside (72) Inventor Hiroshi Mizushima 812, Jomitsucho, Hamamatsu City, Shizuoka Prefecture F-term (reference) 4M118 AB01 BA12 5C024 AA11 CA11 CA16 DA05 EA01 EA10 FA01 FA11 GA07 GA11 GA15 HA07 HA14 JA10 JA21

Claims (8)

[Claims] 1. An electron beam image capturing apparatus comprising: a scintillator for receiving an electron beam image; and a CCD image capturing unit for capturing a light image formed on the scintillator as a two-dimensional image. An electron beam imaging apparatus having a function of using a part of a region as a memory unit. 2. An electron beam image capturing apparatus comprising: a scintillator for receiving an electron beam image; and a CCD image capturing unit for capturing a light image formed on the scintillator as a two-dimensional image. Full frame transfer C
An electron beam comprising a CD, and having a mode in which the entire imaging area of the full frame transfer CCD is used as a light receiving section, and a mode in which the imaging area is divided into a light receiving section and a memory section for use. Image imaging device. 3. The electron beam imaging apparatus according to claim 1, further comprising a movable electron beam shielding plate for shielding a part of an electron beam image receiving area of the scintillator from an electron beam. Electron beam imaging device. 4. An electron gun, an irradiation lens system for irradiating a sample with an electron beam emitted from the electron gun, a lens system for forming an electron beam image by electrons transmitted through the sample, and An electron microscope comprising: the electron beam imaging apparatus according to claim 1, which captures a line image, wherein the electron beam imaging apparatus is configured to perform electronic scanning between high-precision reading and high-speed reading. An electron microscope characterized by changing a line image receiving area. 5. The electron microscope according to claim 4, wherein said high-precision readout includes a CC provided in said electron beam image receiving apparatus.
An electron microscope, wherein the entire imaging area of the D imaging means is used as a light receiving section, and a part of the imaging area of the CCD imaging means is used as a light receiving section and another part is used as a memory section at high speed reading. . 6. The electron microscope according to claim 4, wherein the whole area of the electron beam image receiving area of the electron beam image pickup device is used at the time of high-precision reading, and the entire area of the electron beam image receiving area of the electron beam image pickup apparatus is used at the time of high-speed reading. An electron microscope, wherein a part of a region is shielded by a movable electron beam shielding plate. 7. The electron microscope according to claim 4, wherein a half area of an imaging area of said CCD imaging means is used as a light receiving section during high-speed reading. 8. The electron microscope according to claim 4, wherein at the time of high-speed reading, an area less than half of the imaging area of said CCD imaging means is used as a light receiving section.