JPS62222557A - Stereoscopic observation device - Google Patents

Abstract

PURPOSE:To make possible the observation of a high quality stereoscopic image in the real time by displaying separately on one display device images of a sample corresponding to each of the two incident angles respectively with which a particle beam probe deflected by a locking deflector radiates the sample. CONSTITUTION:Locking deflectors 5-1 and 5-2 deflect an electron beam probe radiating a sample 6 basing on the locking signal so as the incident direction becomes X. A deflector 4 scans the sample 6 with the electron beam probe basing on the deflection signal. The secondary electrons generated from the sample 6 synchronously to the scanning are collected and amplified to be displayed as an image on the left half of the display device 13. Similarly, by deflecting the electron beam probe radiating the sample 6 so as the incident direction becomes Y as indicated in the figure, the secondary electrons generated from the sample 6 are collected and amplified to be displayed as an image on the right half of the display device 13. By observing the two images displayed on the left half and the right half of the display device 13 through a stereoscope 14, the sample 6 can be observed stereoscopically in the real time.

Description

Detailed Description of the Invention [Summary] The present invention provides a three-dimensional observation device configured to scan a sample using a particle beam probe and observe a three-dimensional image of the sample based on the signals generated at this time. A rocking deflector is provided to deflect the angle at which the sample is irradiated using the probe to an arbitrary predetermined angle, and the particle beam probe deflected by the rocking deflector remains associated with the two incident angles at which the sample is irradiated. Each image is displayed in a divided manner on a single display device having optical properties, and a stereoscopic mirror is used to enable stereoscopic observation of the two displayed images.

[Industrial application field]

The present invention relates to a three-dimensional observation device that displays a sample irradiated using a particle beam probe in a divided manner on one display device in real time for three-dimensional observation.

[Conventional technology]

Conventionally, there is a scanning electron microscope that scans a sample using an electron beam probe, detects secondary electrons generated at this time, and displays an enlarged image of the sample on a display. This electron microscope has an extremely deep depth of focus due to the small opening angle of the electron beam probe that irradiates the sample.
The angle of the electron beam probe that irradiates the sample is deflected to two different angles, for example ±4°, and the images obtained at these two different angles are displayed on a color television receiver using red and green. By observing green images through transparent glasses corresponding to each color,
There is a 3D observation device that performs 3D observation in real time.

In addition, there is also a system in which the images obtained at the two different angles are displayed on two different display devices, and the displayed images are stereoscopically observed in real time.

[1. In point to be solved by the invention] The conventional three-dimensional observation device described above generates images generated by irradiating a sample from two different angles on a color receiver in the form of red and green images. Because the display was used for real-time stereoscopic observation, it was necessary to scan the sample at a high speed similar to the horizontal scanning speed of a television (63.5 μs), making it difficult to obtain a sufficient amount of signal from the sample. Because of this difficulty, there were problems in that the image quality was poor and the image flickered, making it impossible to observe a stereoscopic image with a good S/N ratio.

In addition, since the display was performed in red and green on a color receiver, the resolution was limited to 525 horizontal scanning lines according to a predetermined standard, such as the NTSC system, and high image quality, such as 1000 scanning lines, was limited to 525 horizontal scanning lines. There was a problem in that it was not possible to generate high-quality 3D images such as those of books.

Furthermore, images generated by irradiating the sample from two different angles were displayed on two display devices to perform three-dimensional observation in real time.Although the structure is incomplete, it is difficult to use two display devices. In addition, the working distance of the stereoscope to observe the images displayed on the two display devices with two eyes becomes long, and the structure of the stereoscope becomes complicated and expensive. There was a problem that it became large and complicated.

[Means for solving problems]

In order to solve the above problems, the present invention provides a rocking deflector that deflects the angle at which a sample is irradiated using a particle beam probe to an arbitrary predetermined angle, and the particle beam probe is deflected by the rocking deflector. irradiates the sample2
Each image is displayed in a divided manner on a single display device with afterglow properties corresponding to each incident angle, and the two images displayed in this divided manner are displayed in real time using a stereoscopic mirror. This allows for three-dimensional observation.

Next, means for solving the problem will be explained using the configuration of one embodiment of the present invention shown in FIG.

In FIG. 1, an electron beam probe irradiation system (particle beam probe irradiation system) 1 irradiates a sample 6 with a finely focused electron beam (particle wA) probe.
2, and an objective lens (OL>3) that focuses the electron beam 2 emitted from the electron source onto the sample 6.

The deflector 4 scans the position of the electron beam probe (particle beam probe) focused on the sample 6.

7 King deflector 5-1.5-2 deflects the incident angle of the electron beam probe to be focused on the sample 6, for example, as shown using two different angles, X and Y in the diagram. .

The scanning signal generator 7 generates a deflection current (or deflection voltage) or a deflection signal for driving the deflector 4 and the display device 13.

The stereoscopic signal control section 8 includes a locking deflector 5-1.5-2.
2 that detects and amplifies secondary electrons generated from the sample 6 in synchronization with the drive signal and this drive signal.
It supplies a signal for displaying the next electron image on the display device 13 in a divided manner.

The detector toi collects and detects secondary electrons generated when the sample 6 is irradiated with an electron beam probe.

The display device 13 displays, in divided form, an image in which the brightness is modulated using a signal, for example, a secondary electron signal, generated when the sample 6 is scanned using an electron beam probe.

The stereoscopic mirror 14 is for three-dimensionally observing two images displayed in a divided manner on one display device 13.

[Effect]

The structure explained using FIG. 1 is adopted, and the rocking deflector 5
-1 and rocking deflector 5-2 deflect the incident direction of the electron beam probe that irradiates the sample 6, for example, as indicated by X in the figure. In this deflected state, the deflector 4 scans the sample 6 using a finely focused B-like electron beam probe based on the deflection (scanning) signal supplied from the scanning signal generator 7. In synchronization with this scanning, secondary electrons generated from the sample 6 are collected and amplified to display an image on the left half of the display device 13. Similarly, the incident direction of the electron beam probe that irradiates the sample 6 is deflected as shown in the figure Y, and the secondary electrons generated from the sample 6 are collected and amplified, and the display device ll! 13
Display the image in the upper right half. By observing the two images displayed on the left and right halves of the display device 13 through the stereoscopic mirror 14, it becomes possible to stereoscopically observe the sample 6 in rear J'lz time.

As described above, the angle at which the electron beam probe irradiates the sample 6 is kept fixed at two predetermined angles using the rocking deflector 5-115-2, and in this state, the sample 6 is The screen is sequentially scanned for each irradiation position, and the video signal generated at this time is used to display two images in a divided manner on one display device with afterglow property. By observing the image using the stereoscopic mirror 14, it becomes possible to observe a high-quality stereoscopic image in real time.

〔Example〕

Next, the configuration and operation of an embodiment of the present invention will be explained in detail using FIGS. 1 to 3.

In FIG. 1, an electron beam probe irradiation system 1 focuses an electron beam generated by an electron source (not shown) onto a sample 6 as a minute electron beam probe using an OL (objective lens) 3. be.

The deflector (HOR, VER) 4 scans the position of the electron beam probe focused on the sample 6, for example in the horizontal direction (HO
R) and the vertical direction (VER).

The rocking deflector 5-1.5-2 deflects the incident direction of the electron beam probe that irradiates the sample 6 as shown in X and Y in the figure. This makes it possible to generate two images in real time as observed from X and Y in the diagram.

The scanning signal generator 7 supplies a horizontal scanning signal and a vertical scanning signal for scanning the sample 6 to the deflector (HOR, VER) 4, and also supplies a rocking signal to the rocking deflector 5-1.5-2. Horizontal scanning signals, vertical scanning signals, and various synchronization signals (HOR
, VER) and the like to the stereoscopic signal control section 8.

The stereoscopic signal control unit 8 receives the supplied synchronization signal (HOR, V
A predetermined locking signal is supplied to the locking deflector 5-1.5-2 in a manner synchronized with the locking deflector 5-1.5-2. The magnitude of this supplied rocking signal can be arbitrarily adjusted by controlling the voltage supplied from the illustrated battery (reference power source) supplied to points a and b in the figure.

This makes it possible to arbitrarily adjust the rocking angle deflected by the rocking deflectors 5-1 and 5-2.

The detector 10-1 and the amplifier 10-2 collect and amplify secondary electrons generated when the sample 6 is irradiated with the electron beam probe.

The deflection synthesizer 11 includes a stereoscopic signal control section 8 as described later.
In synchronization with the rocking signal supplied from the rocking deflector 5-1. It is something that is synthesized.

The deflection amplifier 12 amplifies the scanning signals (VF, R, HOR) supplied from the deflection synthesizer 11 and drives the display device 13.

The display device 13 includes a stereoscopic signal control section 8, a deflection synthesizer 11,
Based on the signal supplied via the deflection amplifying section 12, two images are displayed in a divided manner on one screen with afterglow properties.

The stereoscopic mirror 14 is used to combine two images displayed on one display device 13 into a stereoscopic image for observation.

Next, the operation of the configuration shown in FIG. 1 will be explained in detail using FIG. 2.

FIG. 2(a) shows the scanning position of the electron beam probe scanned by the deflector 4 over the six surfaces of the sample, and FIG. 2(b) is a table showing two images in a divided manner on the display device 13. Give an example.

As shown in FIG. 2(A), the position of the electron beam probe focused on the sample 6 by the electron beam probe irradiation system 1 is
Using the deflector 4, the surface is sequentially scanned as a first scan, a second scan, a third scan, and so on. This surface scanning is performed using signals generated by the scanning signal generator 7, and is performed in the horizontal direction (HOR) and vertical direction (HOR).
VER), for example, by supplying a predetermined deflection current or deflection voltage so that each sawtooth current flows through the deflection coil 4.

A digitally generated staircase scanning signal may also be provided if desired; the horizontal scanning speed of this sawtooth current is slow to improve the image quality obtained from the sample 6. In this embodiment, for example, the number of scanning lines is 1000, the scanning time of one frame is 10 seconds,
The time for one horizontal scan is 10 ms. This is equivalent to one horizontal scanning time of 63.5 when displayed on a conventional color receiver.
Compared to μs, it is extremely long, making it possible to obtain high-quality images in real time.

In Figure 2 (b), the first, second, third,
The solid line shown using the 4th scan corresponds to the 1st surface scan, and the 1st scan, 2nd scan, 3rd scan, etc. shown in FIG. 2(A).・Indicates what corresponds to etc. As can be seen from these numbers, in this embodiment, the left image and the right image displayed in a divided manner on the display bag 1 (CRT) 13 are alternately interlaced scanned one by one. The image is displayed in .

In this interlaced scanning, firstly, as described above, the deflector 4 uses an electron beam probe to scan the sample as shown in FIG. 6 is sequentially scanned.

Second, a synchronization signal (HOR, V
Based on the ER), the stereoscopic signal control unit 8
When corresponding to the first scan, third scan, etc. shown in FIG. While the electron beam probe is scanning from the direction shown using
Deflect so as to irradiate the sample 6. Similarly, when corresponding to the second scan, fourth scan, etc. shown in FIG. 2(a), a predetermined rocking current (square wave current) is supplied to the rocking deflector 5-1. For example, Y in Figure 1
During the scanning, the electron beam probe is deflected from the direction indicated by the arrow so as to irradiate the sample 6.

Third, in synchronization with the second step in which the sample 6 is irradiated from the X or Y direction in FIG. The scanning signal is switched to either C or d shown in the figure, and the switched scanning signal is supplied to the deflection combiner 11. The deflection synthesizer 11 that has received this scanning signal supplies the scanning signal to the display barrel M13 via the deflection amplifier 12, and as shown in FIG. The divided images are displayed respectively. As a result, predetermined images are displayed at the positions indicated by solid lines in FIG. 2(b).

Fourth, as in the second and third steps, the second
Figure (B) Interlaced scanning is performed so that predetermined images are displayed at the positions indicated by dotted lines in the figure.

As explained above, the deflection current supplied to the deflector 4 is controlled so that the surface of the sample 6 is sequentially scanned by the electron beam probe, and the rocking deflector 5-1.5- is controlled in a manner synchronized with this surface scanning. A video signal generated by supplying a predetermined locking signal to the cathode ray tube (CRT
) By displaying two images in a divided manner on one display device 13, it is possible to observe a stereoscopic image with good image quality.

Next, the operation for displaying two images divided into left and right sides on one display device 13 will be explained using FIG.

In FIG. 3, the upper horizontal scanning signal H8 is a horizontal scanning signal for scanning the sample 6, and is supplied by the scanning signal generator 7 to the deflector (HOR) 4. 1st, 2nd, 3rd, 4th...
By supplying horizontal scanning signal H1 corresponding to The surface of the sample 6 will be scanned.

The horizontal scanning signal HcIIT in the lower part of FIG.
A horizontal scanning signal for scanning CRT) 13,
Among the horizontal scanning signals supplied from the scanning signal generating section 7,
The scanning signals selected by switching in synchronization with the rocking signal generated by the stereoscopic signal control section 8 are supplied to the deflection synthesizer 11 and synthesized. This synthesized horizontal scanning signal HtMT is supplied to the display device 13 via the deflection amplification section 12, and the horizontal scanning signals corresponding to the first, second, third, fourth, etc. in FIG. Signal H
0a to the horizontal deflector (HOR) of the display device 13, and a sawtooth vertical scanning signal cat (not shown) to the vertical deflector (VER).
As shown in FIG. 2 (b), the display device 1f (CRT) 13
Two images divided into left and right sides will be displayed at the top. In this case, the two left and right divided images are synchronized with the manner in which the sample 6 is irradiated from the X direction shown in the figure and the manner in which the sample 6 is irradiated from the Y direction in the figure by the rocking deflector 5-1.5-2. It is switched and displayed, and is generated by supplying to the display device 13 a horizontal scanning signal Hc*r obtained by superimposing a predetermined DC bias on a horizontal scanning signal and synthesizing it.

As described above, by displaying two images in a divided manner on one display device 13 and observing these two images using a stereoscope, it becomes possible to perform stereoscopic observation in real time. .

In this embodiment, a case has been described in which the sample 6 is irradiated with an electron beam probe for stereoscopic observation. However, the present invention is not limited to this, and other particle beams such as ions may also be used.
Similarly, it can be observed in three dimensions. In this case, due to the nature of ions, the electron beam probe irradiation system 1 in FIG. 4 becomes an electrostatic deflector, and locking deflector 5-1.5-2 becomes an electrostatic rocking deflector.

(Effects of the Invention) As described above, according to the present invention, a rocking deflector is provided that deflects the angle at which a sample is irradiated using a particle beam probe to an arbitrary predetermined angle, and the particle beam is deflected by the rocking deflector. Two images are displayed in a divided manner on a single display device with afterglow properties corresponding to the two incident angles at which the sample is irradiated by the particle beam probe, and these images are displayed using a stereoscopic mirror. Since it adopts a configuration that allows stereoscopic observation of two images, it is possible to observe high-quality stereoscopic images in real time.In particular, since the scanning speed can be arbitrarily selected, it is possible to observe two images in three dimensions. Scan and high S
/N ratio and high resolution stereoscopic images can be observed in real time. Furthermore, since interlaced scanning is performed and the display device has an afterglow property, it is possible to observe a three-dimensional image with less flicker. Furthermore, because it uses a configuration in which two images are displayed in a divided manner on one display device and a stereoscopic image is observed in real time using a stereoscopic mirror, only one display device is required and the structure is simple. At the same time, the structure of the stereoscopic mirror becomes simple.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, FIG. 2 is a display example, and FIG. 3 is a scanning signal example. In the figure, 1 is an electron beam probe irradiation system, 2 is an electron beam, 3 is an objective lens (OL), 4 is a deflector, 5-1.5-2 is a rocking deflector, 6 is a sample, and 7 is a scanning signal generator. 8 is a stereoscopic signal control unit, 11 is a deflection synthesizer, 13 is a display device,
14 represents a stereoscopic mirror.

Claims (1)

[Claims] In a three-dimensional observation device configured to scan a sample using a particle beam probe and observe a three-dimensional image of the sample based on the signals generated at this time, a particle beam probe is generated and the sample is irradiated. a particle beam probe irradiation system that scans the position of the particle beam probe generated by this particle beam probe irradiation system and irradiates the sample surface; A rocking deflector that deflects the incident angle to an arbitrary predetermined angle; a detector that detects a signal generated by irradiating a sample with a particle beam probe; One display device that displays in a manner with optical properties; and a three-dimensional device that displays signals detected by the detector in correspondence with the incident angles with respect to the sample in a divided manner on one display device. and a signal control unit, which uses the rocking deflector to deflect the incident angle at which the particle beam probe irradiates the sample to two arbitrary angles, and displays information on one of the display devices corresponding to the two angles. 1. A stereoscopic viewing device characterized by displaying each image in a divided manner and using a stereoscopic mirror to perform stereoscopic observation of the two images displayed on one display device.