JPS5848042B2 - Method for detecting deviation between electron beam and material movement direction - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting a deviation between an electron beam and a moving direction of a material, and more specifically, the present invention relates to a method for detecting a deviation between an electron beam and a moving direction of a material. The present invention relates to a method for detecting a deviation or inclination of a projected material from a moving direction.

Conventionally, in a device such as an electron beam exposure device that draws a figure on a material using an electron beam, a desired figure is filled in by scanning a minute diameter electron beam.

However, this method takes too much time to draw large-area figures, so recently it has been proposed to project an electron beam with a rectangular cross section of relatively large area onto the material and scan the electron beam on the material. A device that can draw large-area figures in a short time has been proposed.

In the above proposed device, the cross section of the projected electron beam is rectangular, so it has directionality, and when scanning the electron beam on a material, it is necessary to move it in the direction along the sides of the rectangle, and the material also needs to be moved. The moving direction of the material when moving the scanning range of the electron beam must also be along the direction of the sides of the rectangle.

If the material is moved intermittently when the direction of movement of the material and the direction of the sides of the rectangle do not match, the scanning range should move in a single strip as shown in Figure 1a. In reality, the scanning range gradually shifts, which is not desirable, as shown in FIG.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a method capable of detecting a deviation, that is, an inclination, between the side direction of an electron beam and the moving direction of a material.

The present invention will be explained in detail below based on the drawings.

FIG. 2 is a block diagram showing an example of an electron beam exposure apparatus for carrying out the method according to the present invention, and the button 1 in the figure is an electron gun.

An electron beam generated by an electron gun 1 is projected onto a first slit 3 via a lens 2.

The electron beam B1 that has passed through the square electron beam passage opening (size 100 μm x 100 μm) provided in the slit 3 is deflected by the first deflector 5 to which the deflection signal from the deflection signal generation circuit 4 is supplied. , is projected through a lens 6 onto a second slit 7 having exactly the same shape as the first slit 3.

The electron beam B2 that passed through the opening provided in the slit plate 7
is reduced to 1/10 by a lens 8 and projected onto a material 10 fixed on a movable table 9, and is also projected onto the material 10 by a second deflector 12 to which a scanning signal from a scanning signal generation circuit 11 is supplied. Peeled and scanned.

Electrons generated from the material by irradiating the material with an electron beam are detected by a detector 13 .

After the obtained detection signal is amplified by the amplifier 14,
A-D is supplied to the grid 16 of the cathode ray tube 15
It is sent to the central processing unit 18 via the converter 17.

The processing device 18 generates a command signal and sends it to the deflection signal generation circuit 4 and the scanning signal generation circuit 11.

Furthermore, the processing device 18 sends a transfer signal to the moving mechanism 19 to move the movable table 9 appropriately.

Further, the deflection coil 20 of the cathode ray tube 15 is supplied with a scanning signal from the scanning signal generating circuit 11.

By pressing the button in the above-described manner, the image of the first slit 3 is projected onto the second slit 7 via the lens 6 at a magnification of 1x.

That is, an electron beam B1 having a square cross section with one side of 100 μm is projected onto the second slit 7.

Here, according to a command from the central processing unit 18, the electron beam B1
If it is projected to the position shown in FIG. 3a, a thin electron beam B2P passing through one corner P of the opening of the second slit 7 will be obtained.

Then, the electron beam B2P is reduced to 1/10 and projected onto the material via the lens 8, and is scanned two-dimensionally within a certain area zP by the second deflector 12.

Electrons generated from area zP by this scanning are detected by detector 1.
3, and the obtained detection signal is supplied to the grid 16 of the storage type cathode ray tube 15 as a luminance signal.

At this time, the electron beam inside the cathode ray tube 15 is deflected by the deflection coil 20.
Since the electron beam B2P is scanned in synchronization with the scanning of the electron beam B2P, an electron beam scanned image of the area ZP is obtained and accumulated on the screen of the cathode ray tube 15.

The above is the first step of the present invention. Next, central processing unit 1
8 is sent to the moving mechanism 19 to move the material an appropriate distance, for example 10 μm, in a predetermined direction.

This is the second stage. Further, in response to a command from the central processing unit 18, the electron beam B1 is projected to the position shown in FIG.

Then, the electron beam B2Q is reduced to 1/10 and projected onto the material through the lens 8, just like the first beam n, and is two-dimensionally scanned within a certain area ZQ by the second deflector 12. be done.

As a result, the area ZQO image is displayed on the screen of the cathode ray tube 15, superimposed on the area ZPO image obtained previously and continuously displayed. be done.

This is the third stage.

By the way, the electron beam B2P scanning the area ZP and the electron beam B2Q scanning the area ZQ are 100 μm apart at the position of the second slit 7, as shown in FIG. If the second
If it is not deflected by the deflector 12, the electron beam B2P
, B2Q are projected onto the button material 10 in FIG. 4 at a position indicated by diagonal lines at a distance of 10 μm.

The part surrounded by the broken line in the same figure shows that the opening of the second slit 7 is 1.
It is projected after being reduced to /10, and the direction of this broken line is the direction of the side of the electron beam.

In this way, the electron beams B2P and B2Q are projected onto the material with a distance of 10 μm, so naturally the electron beams B2P and B2
The scanning areas ZP and ZQ by Q are also 10 μm apart on the material in the direction of the side of the electron beam.

Therefore, for example, if we focus on the reference mark S provided on the material, the mark S will be located in the area ZPO obtained in the first step.
The button on the image is displayed as SP as shown in FIG.

When the material is moved by 10 μm in the second step, the reference mark is correctly S in the direction of the side of the electron beam.

If it moves at an angle θ with respect to the side direction and comes to the position S1, then
When the area ZQO image is obtained in the third stage, the reference mark S is the fifth
It is displayed as SQ shown in the figure, and a vertical shift f occurs in the display position of the reference mark in the image.

It is clear from Figure 4 that the following equation exists between the deviation f and the angle θ at this time. Therefore, by knowing the deviation f and the image magnification M, we can determine the direction of the side of the electron beam and the movement of the material. The angle θ formed with the direction can be determined.

Then, by correcting the inclination of the side direction of the electron beam and the moving direction of the material by processing such as rotating the material based on the obtained angle θ, it is possible to make both directions coincide.

Also, it can be confirmed that both directions coincide with each other by seeing that the deviation between the image of area ZP and the ZQO image becomes zero.

In the above description, the deviation f is determined from the screen of the cathode ray tube 15, but the present invention is not limited to this.
For example, the processing device 18 may detect the positions of the same reference marks provided on the material based on the signals corresponding to the area ZP and ZQo images, and calculate the inclination θ from the deviation of the positions. In this way, it is possible to automate the process.

Furthermore, in the above-described embodiments, the case where the side direction of the cross section of the electron beam and the scanning direction of the electron beam are parallel to each other is explained.
It goes without saying that the scanning direction of the electron beam may be any direction.

Furthermore, in the above-mentioned embodiments, the case where the cross section of the electron beam is rectangular has been explained, but this is not limited to the case where the electron beam has a polygonal cross section created using a slit having a polygonal opening. It is possible to detect the deviation between the direction of one side of the material and the direction of movement of the material.

As described in detail above, according to the present invention, it is possible to detect the deviation between the direction of the side of the cross section of the electron beam and the direction of movement of the material, and the effect thereof is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the deviation between the side direction of the cross section of the electron beam and the moving direction of the material, and FIG. 2 is a configuration diagram showing an example of an apparatus for implementing the present invention. Further, FIGS. 3, 4, and 5 are diagrams for explaining the operation of the apparatus shown in FIG. 2. 1: Electron gun, 2, 6, 8: Lens, 3, 7: Slit, 4: Deflection signal generation circuit, 5.12: Deflector, 9: Movable base, 10: Material, 11: Scanning signal generation circuit, 13 : Detector, 14: Amplifier, 15: Storage type cathode ray tube, 16: Grid, 17: A-D converter, 18: Central processing unit, 19
: Moving mechanism, 20: Deflection coil.

Claims (1)

[Claims] 1. From the electron beam forming means having a polygonal cross section, which includes front and rear slits having polygonal openings arranged on the electron beam path and deflection means arranged between the slits, to the polygonal opening of the rear slit. Taking out an electron beam passing through one end of one side and projecting it onto the material, scanning the electron beam on the material using a second deflection means, moving the material after scanning, and after moving the material. Taking out an electron beam passing through the other end of the side of the polygonal opening of the rear slit from the forming means and projecting it onto the material, and scanning the electron beam on the material using the second deflection means. , the direction of the side of the electron beam with a polygonal cross section and the direction of movement of the material should be avoided by determining the relative positional relationship of the reference target part on the material based on the information obtained from the material by each of the above electron beam scans. How to detect the deviation between.