JP2001084940A - Scanning electron microscope provided with sample- changing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scanning electron microscope provided with a highly reliable holding and dismounting mechanism allowing a sample to be changed on a sample table and a sample transfer device which allow the sample table to be easily be extracted from a sample changing chamber and replaced. SOLUTION: This scanning electron microscope provided with a sample transfer device. The microscope is so structured that when a lever receiver mounted to a lever (sample) in a sample table 6 is moved from the tilt part of a spring-pushed lever in a sample changing chamber 8 to a parallel part thereof by the movement of the sample table 6, the lever (sample) is rotated, and the sample stopper separates from the sample 11 and moves to the sample transfer device 9, and the sample table 6 can be changed by mounting a push catch allowing it to be mounted to and dismounted from the spring-pushed lever and by combining them with each other.

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 apparatus for measuring and observing a wafer, a mask, etc., on which a resist pattern of a semiconductor is formed. The present invention relates to a scanning electron microscope provided with a sample transfer device having a method for reducing processing time and cost.

[0002]

2. Description of the Related Art A sample holding mechanism used in a current scanning electron microscope changes a pressure difference between a vacuum in a sample chamber and a sample exchange chamber into a spring force by a bellows, and fixes the sample to a sample stage only in a vacuum. It was unreliable because it could not be checked in the atmosphere, that is, in a normal state, and in a held state. The current spring mechanism also has a complicated structure and lacks reliability. Further, the exchange of the sample table in the sample exchange chamber must be performed by using a tool, and the workability is deteriorated.

[0003]

In the sample chamber of the scanning electron microscope, a sample (wafer, mask) must be securely held on the sample table, and a mechanism for easily exchanging the sample is required in the sample exchange chamber. Become.

Further, a structure has been required in which a sample table in a sample exchange chamber can be easily replaced when a sample is changed.

At present, the bellows method of fixing a sample is inferior in holding reliability. The spring method also has a complicated structure and lacks reliability. There was also a problem that the workability was poor when replacing the sample table.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sample changing apparatus having a sample table which has a simple structure and is easily detachable, in which the sample is securely held and mounted on the sample table, reliability is improved, and the sample table is easily attached and detached.

[0007]

In order to achieve the above object, in the sample chamber, the sample is held down by the lever of the sample stage, and in the sample exchange chamber, the sample is moved along the inclined lever so that the sample can be exchanged reliably. Then, an exchanging device in which the detachable mechanism is integrated with the tilt lever is provided so that the sample stage lever is operated to release the sample, and the sample stage can be easily exchanged depending on the type of the sample.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.

FIG. 1 is a configuration diagram of a scanning electron microscope provided with a sample transfer device. An electron beam is generated by the electron gun,
Further, the electron beam is accelerated and focused by a condenser lens and an objective lens.The converged electron beam irradiates the sample, and the secondary electrons emitted from the sample are displayed on a CRT for observation by a secondary electron detector. There is a mirror body 1.

A vacuum is maintained in the sample chamber 2 by an exhaust system, and the sample stage 3 is driven in the X and Y directions. The sample stage 2 is driven by an X stage drive motor 4 and a Y stage drive motor 5 to move to a predetermined position in a horizontal plane, and the sample is irradiated with an electron beam. Further, it moves to the transfer position of the sample table 6 and exchanges the sample table 6 with the sample exchange chamber 8.

The sample exchange chamber 8 is a spare chamber for receiving and transferring the sample table 6, and also exchanges the sample 11 held on the sample table 6 with the sample transfer device 9. At the time of the preparatory room, it is in a closed state and is in a vacuum state. Further, when the sample is delivered, the sample is opened and the atmosphere becomes the atmosphere.

The sample transfer device 9 is a device for transferring the sample 11 from the sample table 6.

FIG. 2 shows an embodiment of the present invention. FIG. 2 is a view in which the sample exchange chamber 8 is in an open state.
Further, the AV gate 10 that allows the sample table 6 to be replaced by vertical drive, guides L, R12, and 13 that guide the sample table 6 to a fixed position in the sample exchange chamber 8, and a chuck unchuck 21 that chucks the sample table. , A ball screw 24 for driving the sample stage 6 via the chuck unchuck 21, an LM guide 23 for guiding the ball screw 24, a chuck unchuck lever 12 for releasing and setting the chuck unchuck 21 from the sample stage 6, It comprises a chuck driving device 27 and a motor driving device 28 for driving the ball screw 24 via the casings A, B 25 and 26. The sample stage 6 is provided with a lever holder 1 which is in contact with a sample holder 18 for holding a sample (wafer, mask) and a spring pressing lever 20.
9 comprises a lever (sample stage) 15 and a spring 17 held by a spring holder 16 for applying a spring force for holding the sample.

The holding and operation of the sample 11 on the sample stage according to the present invention will be described. The AV2 gate 10 moves downward, the sample chamber 2 is opened, and the chuck 6 of the chuck unchuck 21 moves the sample stage 6 from the sample chamber 2. Withdrawn,
It moves along guides L, R12 and 13. The lever receiver 19 of the lever (sample) 15 in the sample table 6 comes into contact with the spring pressing lever 20, and the sample holder 1 against the spring force of the spring 17.
8 is separated from the sample 11 and is completely released at the replacement position of the sample 11. Thereafter, the sample exchange chamber 8 is opened, and the sample 11 is taken out from the sample taking-out lever 29 of the sample carrying device 9 to the sample carrying device 9 and carried. The loading of the sample 6 goes from the sample exchange chamber 8 to the sample chamber 2 through the reverse process.

FIG. 3 is a detailed view of the mechanism of the present invention for releasing the holding of the sample 11 on the sample stage.

The lever (sample) 15 of the sample stage 6 is the sample 11
When the lever receiver 19 of the lever (sample) 15 approaches the parallel portion along the inclined surface of the spring pressing lever 20, when the lever holder 19 approaches the release position, the sample holder 18 resists the spring force of the spring 17 and the lever ( The sample 15 is rotated and released from the sample 11.

At this time, the spring force of the spring 17 acts perpendicularly to the parallel portion of the spring pressing lever, and can be set to a stable position without making a movement for moving the sample stage forward. FIG. 4 shows the sample stage 6 after passing through the AV2 gate 10,
FIG. 5 shows a state in which the lever receiver 19 of the lever (sample) 15 is in contact with the inclined surface of the spring pressing lever 20, and FIG. 6 shows a state in which the sample is released, and the lever receiver 19 is in a parallel part of the spring pressing lever 20. 4 to 6 show the positional relationship between the lever (sample) 15 and the spring pressing lever 20. In FIGS. 5 and 6, the lever holder 19 operates on the inclined portion and the parallel portion of the spring pressing lever 20 according to the present invention. Understand the state of going. By this operation, the sample holder 18 is separated from the sample and released against the spring force of the spring 17.

FIG. 7 shows that the sample stage 6 is easily detached.
FIG. 4 is a mechanism diagram in which a detachable mechanism is mounted on the spring pressing lever 20. As shown, the spring pressing lever 20 is integral with the two guides 44. Furthermore, the shaft and the hole structure are easily detachable from the lever fixing member 35. Also,
The pushcatch 30, in which the spring C30, the body 33, the upper and lower sliders 32, and the rotor 36 are incorporated, is attached to a fixed height and detached. The body 33 is provided with a movable base fixing member 37 which moves horizontally and horizontally so that the upper and lower sliders 32 can be easily inserted, and incorporates a moving base 38 for fixing the rotor 36 after the insertion. The principle of operation will be described with reference to FIGS. FIG. 8 shows that the spring pressing lever 20 is driven by the spring force of the spring C30.
The vertical slider 32 moves upward, but the position of the movable base 37 is regulated by the lock mechanism of the rotor 36, and the movable base 37 is maintained at a constant height. As shown in FIG. 9, the mechanism according to the present invention has been adopted to easily attach and detach the sample stage 6, in which the spring pressing lever 20 must be removed. When the spring pressing lever 20 is pressed from above, the spring C30 contracts, the body 33 moves downward, and the body 3
The rotor 36 mounted on the upper and lower sliders 3
By the claw 2, the sushi is rotated and the fixing is released, and the spring pushing lever 20 with the push catch 31 and the guide 34 integrated with each other is detached.

As a result, the sample table 6 can be easily removed. If this operation is reversed, the sample table 6
Can be easily mounted.

[0020]

According to the present invention, the reliability of holding the sample on the sample stage is remarkably improved, the mechanism is simple and the size can be reduced, and the sample stage can be moved from the sample exchange chamber. A sample exchange device that facilitates exchange can be provided.

[Brief description of the drawings]

FIG. 1 is an original external view of a scanning electron microscope provided with a sample transfer device according to the present invention, and a partial cross-sectional view thereof.

FIG. 2 is a detailed view of a sample exchange chamber according to the present invention.

FIG. 3 shows a lever (sample) in the sample exchange chamber according to the present invention.
FIG. 4 is a principle view showing the operation of a spring pressing lever.

FIG. 4 is a diagram showing a relationship between operating positions of a sample stage, a lever (sample), and a spring pressing lever in a sample exchange chamber according to the present invention.

FIG. 5 is a diagram showing the relationship between the operating positions of a sample stage, a lever (sample), and a spring pressing lever in a sample exchange chamber according to the present invention.

FIG. 6 is a diagram showing a relationship between operating positions of a sample stage, a lever (sample), and a spring pressing lever in a sample exchange chamber according to the present invention.

FIG. 7 is a diagram of an apparatus according to the present invention in which a detachable mechanism is incorporated in a spring pressing lever for exchanging a sample stage.

FIG. 8 is a diagram illustrating the principle of a detachable mechanism of a spring pressing lever for exchanging a sample stage according to the present invention.

FIG. 9 is a diagram illustrating the principle of a detachable mechanism of a spring pressing lever for exchanging a sample stage according to the present invention.

[Explanation of symbols]

3 sample stage, 8 sample exchange chamber, 9 sample transfer device, 15 lever (sample), 17 spring, 18 sample holder, 19 lever receiver, 31 push catch.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuo Aoki 882 Momo, Oaza-shi, Hitachinaka City, Ibaraki Prefecture Within the Hitachi Measuring Instruments Group, Ltd. 500 500 Hitachi Naka Electronics Co., Ltd. F term (reference) 2G001 AA03 BA07 CA03 GA01 GA06 HA13 JA12 JA14 KA03 LA11 MA05 PA01 PA02 PA06 PA07 PA11 QA01 4M106 AA01 AA09 BA02 CA70 DH24 DH60 5C001 AA01 AA02 AA07 CC04

Claims (2)

[Claims] A scanning electron microscope for measuring a fine pattern size and the like of an integrated circuit formed on a semiconductor wafer and a mask (hereinafter, referred to as a wafer and a mask) using an electron beam. In order to be able to move to a predetermined place arranged inside, the sample chamber can be opened and closed by a gate valve that shuts off the chamber and the sample chamber to exchange the sample, and the sample can be loaded and unloaded. A sample exchange device that exchanges samples with a sample stage in a sample exchange room, and uses a link that moves along an inclined lever and a spring structure as a mechanism for holding the sample on the sample stage. Scanning electron microscope equipped with. 2. A scanning electron microscope equipped with a sample transfer device according to claim 1, further comprising an inclined lever having a vertically movable and fixed structure by a spring which can be easily removed when attaching and detaching the sample stage. A scanning electron microscope having a sample exchange device.