JPH0574695A - Electron-beam plotting device - Google Patents

Abstract

PURPOSE:To obtain an electron-beam plotting device which is less in vibration by separating a vacuum vessel for housing a driving mechanism and another vacuum vessel for housing a sample moving table from each other and separately fixing the vessels to a stool. CONSTITUTION:A sample chamber 2 provided with an electronic optical system 1 on its upper surface and a sample moving table 5 in its inside and a driving chamber 3 provided with a motor 4, ball screw 6, and nut 7 are separated from each other and separately fixed to a stool 9. The chambers 3 and 2 are connected to each other through bellows 12 and the nut 7 is connected to the table 5 by means of a connecting shaft 13. Therefore, the vibration of the system 1 can be prevented and a highly accurate electron-beam plotting device can be obtained, because vibrations produced by the driving section are damped by the stool having a low natural frequency and hardly transmitted to the chamber 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus, and more particularly to an electron beam drawing apparatus.

[0002]

2. Description of the Related Art In a conventional apparatus, a drive mechanism (motor, ball screw, ball nut, etc.) for driving a sample moving table is provided in a vacuum container, or another vacuum container is made and the drive mechanism is provided in the container. Was provided, and the sample moving table was connected via some coupling mechanism.

[0003]

In the conventional apparatus, the vibration due to the rotation of the motor, the vibration of the ball screw and the ball nut at the time of reversing the forward direction, etc. are directly transmitted to the vacuum container in which the sample moving table is housed, and the vacuum is maintained as it is. The electro-optical system provided on the container is vibrated, which causes deterioration of accuracy.

[0004]

According to the present invention, a vacuum container containing a drive mechanism and a vacuum container containing a sample moving table are separated from each other, and each of them is fixed to a surface plate having a sufficient weight, and two vacuum chambers are provided. The above-mentioned problems were solved by connecting the containers with a bellows which does not easily transmit vibration.

[0005]

[Operation] By separating the vacuum container on the side of the drive mechanism from the vacuum container on the side of the sample moving table, it is possible to prevent the vibration generated by the drive source from being directly transmitted to the container on the side of the sample moving table, and to generate it on a surface plate with a sufficient weight. It transmits all the movements made and absorbs vibration.

The connecting portion between the drive mechanism and the sample moving table is
It is connected by bellows to make it difficult to transmit vibration.

From the above, the vibration generated from the drive source is
It is not transmitted to the electron optical system, and deterioration of accuracy can be prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a schematic diagram of a conventional device. The sample moving table 5 is housed in the sample chamber 2, and the electron optical system 1 is mounted on the sample chamber 2. A drive chamber 3 is attached to the sample chamber 2, a ball screw 6 and a nut 7 are provided therein, and the nut 7 and the sample moving table 5 are connected by a connecting shaft 13. A motor 4 is attached to the outside of the drive chamber 3 and is connected to the ball screw 6 via a vacuum seal. A sample exchanging device 8 is attached to the sample chamber 2. The sample chamber 2 and the sample exchanging device 8 are fixed to a surface plate 9 and evacuated by a vacuum exhaust device 11. The surface plate 9 is made difficult to transmit floor vibrations by the air spring 10.

FIG. 2 shows a schematic diagram of this embodiment. Drive room 3
Are separated from the sample chamber 2 and fixed to the surface plate 9 with each other. The portion through which the connecting shaft 13 passes is vacuum-sealed by the bellows 12. A detailed view of the connecting portion is shown in FIG. Weld flange 16 to bellows 13
6 is vacuum-sealed with an O-ring 14 and is attached to the drive chamber 3 and the sample chamber 2.

In this embodiment, the vibration generated by the driving source is transmitted to the surface plate 9 as it is, and the natural frequency of the surface plate is
As low as 5 Hz or less, the generated vibration of 50 to 200 Hz is
It is attenuated by the surface plate 9 and does not reach the sample chamber 2. Therefore, the electron optical system 1 also does not vibrate, and deterioration of accuracy can be prevented.

FIG. 4 shows another embodiment. Although an O-ring 15 is used instead of the bellows 12, the same effect can be obtained. This method is advantageous in terms of downsizing of the apparatus and cost, but there is a problem in terms of friction resistance and vacuum seal reliability.

[0013]

According to the present invention, it is possible to obtain a highly accurate electron beam drawing apparatus which is not affected by the vibration of the driving source.

[Brief description of drawings]

FIG. 1 is a schematic view of a conventional device.

FIG. 2 is a schematic diagram of an embodiment of the present invention.

FIG. 3 is a detailed view of a connecting portion.

FIG. 4 is a diagram showing another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electro-optical system, 2 ... Sample chamber, 3 ... Drive chamber, 4 ... Motor, 5 ... Sample moving base, 6 ... Ball screw, 7 ... Nut, 8
... sample exchange device, 9 ... surface plate, 10 ... air spring, 11 ... vacuum exhaust system, 12 ... bellows, 13 ... connecting shaft, 14 ... O-ring, 16 ... flange.

Claims (2)

[Claims] 1. An electron gun for generating an electron beam, an electron lens for reducing the electron beam and forming an image on the sample, a deflector for deflecting the electron beam, a sample moving table for moving the sample, and a sample. In the electron beam drawing apparatus including a sample exchanging device for exchanging the sample, an exhausting device for evacuating the vacuum, a pedestal for mounting each device, and a control device for controlling them, a driving mechanism for driving the sample moving table is An electron beam drawing apparatus characterized in that vibration transmission is insulated by separating it from a vacuum container accommodating a moving table and providing it in another vacuum container. 2. The electron beam drawing apparatus according to claim 1, wherein the two vacuum vessels are fixed on a surface plate having a sufficiently large capacity, and are connected to each other via a bellows. .