JPH05144399A - Scanning electron microscope - Google Patents

Abstract

PURPOSE:To move an observation visual field smoothly by displaying an electron beam scanning position on a sample and a relationship between respective coordinate axis systems in a mechanical visual field movement and an electromagnetic visual field movement as a three-dimensional image. CONSTITUTION:Signals from a sample stage positioner 12 to convert a sample stage shape inputted from an operation table 16 and a mechanical visual field moving distance into electric signals and a control section 15 capable of converting an electromagnetic visual field moving distance into electric signals, are used to be processed by means of an operation processing section 17. An image 20 to display a sample stage condition and an electron beam scanning position together with coordinate axis systems to show directions of a mechanical visual field movement and an electromagnetic visual field movement as a three-dimensional graphic, can be obtained. An observation visual field moving operation can be carried out smoothly by seeing the image and an observation image 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning electron microscope, and more particularly to moving a sample.

[0002]

2. Description of the Related Art Methods of moving an observation visual field in a scanning electron microscope include mechanical visual field movement and electromagnetic visual field movement, each of which has a coordinate axis system. Therefore, when moving the field of view to display the portion to be observed, XY in moving the sample
If the X-Y directions of the axis and deflection scanning are different, the field of view must be moved after the operation for recognizing the scanning position of the electron beam on the sample and the mechanical structure of the sample stage, which is easy to use. It wasn't taken into consideration.

[0003]

In the above-mentioned prior art, when the XY axis in the sample movement and the XY direction in the deflection scanning are different, when the observation field of view is moved to another desired portion, the sample is moved. As an operation for recognizing the scanning position of the electron beam and the mechanical structure of the sample stage, it is necessary to reduce the magnification and move the field of view, which consumes a lot of time.

An object of the present invention is to provide a scanning electron microscope capable of smoothly moving an observation visual field by displaying the state of the sample stage and the scanning position of the electron beam together with coordinate axis display as a three-dimensional graphic image. Is to provide.

[0005]

In order to solve the above problems, the present invention takes the following means.

(1) The scanning position of the electron beam on the sample is represented by using the orbit of the electron beam irradiating the sample, the contour of the sample table on which the sample is placed, and the surface formed by the contour, and the machine is used for these. A means for adding a XYZ axis in moving the visual field and an XY axis in moving the electromagnetic field to display it three-dimensionally as a graphic image.

(2) Means for sequentially changing the image according to (1) according to the movement of the observation visual field.

[0008]

The relationship between the coordinate axis system in the mechanical visual field movement and the electromagnetic visual field movement in the state of the sample stage and the scanning position of the electron beam can be instantly recognized, and the observation visual field can be moved smoothly.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a general structure of a scanning electron microscope to which the present invention is applied. In the figure, 1 is an electron gun, 2 is an electron beam,
3 is a converging lens for converging the electron beam 2, 4 is a deflection coil for deflecting the electron beam 2 in the X direction and the Y direction, 5 is a field moving electromagnetic coil, 6 is an objective lens,
Reference numeral 7 is a sample, and 8 to 11 are sample moving devices for mechanically moving the visual field. By operating 8 to 11 to move the sample, the 12 sample stage positioners output signals having information on the position of the sample stage. Thirteen
Is a deflection coil power supply, and 14 is a visual field movement coil power supply, which are respectively connected to the control unit 15 and supplied with a control signal.
Reference numeral 16 is an operation console, which can input the shape of the sample table and move the electromagnetic field of view through the control unit 15. Console 1
By electromagnetically moving the visual field at 6, the control unit 15 not only supplies a control signal to the coil power supplies 13 and 14, but also outputs a signal having information regarding the visual field movement.
Using the shape of the sample stage and the signals from 12 and 15,
By processing in the arithmetic processing unit 17, the state of the sample stage and the scanning position of the electron beam are obtained along with a coordinate axis system showing the directions of the mechanical visual field movement and the electromagnetic visual field movement, and an image 20 represented by a three-dimensional graphic is obtained. Reference numeral 18 is a detector for secondary electrons, reflected electrons, etc., and an observation image 21 is obtained via the A / D converter 19. Reference numeral 22 is a display unit for these images.

In the scanning electron microscope without 12, 17 and 20, parallel movement of the sample by the sample moving devices 8 to 11,
Recognize the scanning position of the electron beam on the sample and the XYZ direction in the mechanical visual field movement from the observation image when the visual field is electromagnetically rotated by performing rotational movement, tilt movement, etc. I can't. Therefore, when observing another desired portion by moving the visual field, it takes a lot of time to select a desired visual field.

Since this apparatus is provided with 12, 17, and 20, the scanning position of the electron beam on the sample can be seen as a three-dimensional graphic image on the image 20, and the mechanical field of view is included in the image. It is possible to recognize the XYZ axis in movement and the XY axis in electromagnetic field movement.

Next, referring to FIG. 2, the image 20 according to the present invention.
A display example of is shown. In the figure, 23 is the trajectory of the electron beam irradiating the sample, and 24 is the sample stand. 25 is an XYZ axis in mechanical visual field movement, and 26 is an XY axis in electromagnetic visual field movement. 27 is a mark for indicating a mechanical rotational movement.

From the display example of FIG. 2, the current observation image is X
It can be seen that it is an image when scanning a certain roll on the -Y plane. Further, since the X and Y directions of the coordinate axes of 25 and 26 are the same, it can be seen that when the sample is moved in the X direction by the XY stage 10, the observed image moves in the horizontal direction. Next, when the sample is rotated clockwise on the rotary stage 8, the mark 27 moves accordingly, and the observation image moves from the upper right to the lower left. When the sample is tilted on the tilt stage 9, it tilts about a straight line connecting the mark 27 and the origin.

Since the XY directions of the coordinate axes of 25 and 26 are different from the display example of FIG. 3, even if the sample is moved in the X direction by the XY stage 10, the observed image is almost vertical. You can see it moves.

As described above, since it is possible to recognize how the observation image moves when the sample moving devices 8 to 11 are operated from the graphic image 20, the observation visual field is smoothly moved to a desired position. This improves the operability.

[0017]

As is apparent from the above description, according to the present invention, the following effects can be achieved. That is,
The scanning position of the electron beam on the sample and the mechanical structure of the sample stage can be recognized without operating the apparatus, and a scanning electron microscope with good operability in field of view can be provided.

[Brief description of drawings]

FIG. 1 is a general configuration diagram of a scanning electron microscope to which the present invention is applied.

FIG. 2 is a diagram showing a display example of a graphic image 20 in FIG.

FIG. 3 is a diagram showing a display example of the same.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electron gun, 2 ... Electron beam, 3 ... Converging lens, 4 ... Deflection coil, 5 ... Visual field moving electromagnetic coil, 6 ... Objective lens, 7 ... Sample, 8 ... Rotation stage, 9 ... Tilt stage,
10 ... XY stage, 11 ... Z stage, 12 ... Sample stage positioner, 13 ... Deflection coil power supply, 14 ...
Electromagnetic coil power supply, 15 ... control unit, 16 ... operator console, 17 ...
Arithmetic processing unit, 18 ... Detector, 19 ... A / D converter,
20 ... Graphic image, 21 ... Observation image, 22 ... Image display unit, 23 ... Electron beam trajectory, 24 ... Specimen stage, 25 ... Coordinate axis in mechanical visual field movement, 26 ... Coordinate axis in electromagnetic visual field movement, 27 ... Rotation position Display mark.

Claims (2)

[Claims] 1. A means for three-dimensionally displaying a state of a sample stage and a scanning position of an electron beam as a graphic image, and an XYZ axis in a mechanical visual field movement and an electromagnetic visual field movement in the image. And a means for displaying the X-Y axes in the scanning electron microscope. 2. A scanning electron microscope comprising a means for sequentially changing the graphic image obtained by the means according to claim 1 in accordance with the movement of the sample.