JPS5818850A - Sample shifting device - Google Patents

Abstract

PURPOSE:To obtain a sample shifting device which has a smooth movement and can realize an ultrahigh vacuum in a short time by guiding the power transmitting system of the device to driving contact parts and movable tables by taking advantage of only rolling contact, and preparing the parts of the device from a stainless steel. CONSTITUTION:The linear movement of a shaft 41, which extends from a linear introducer 35 and is guided by bearings 40 with rolling contact, is transferred to a movable table 38 having a rolling-contact guiding surface 48 so as to move the table 38 in the directions indicated by the arrow 31. A linear introducer 34 moves a shaft 37, which is guided by the rolling contact of bearings 36, in the directions indicated by the arrow 31. Next, the direction of the movement of the shaft 37 is changed by 90 degrees through a lever 42 by using a shaft 50 as a supporting point, thereby moving a movable table 43 having a rolling-contact guiding surface 49. Since all parts of the sample shifting device is made from a stainless steel, the device can be baked at above 200 deg.C. As a result, the amount of gas discharged from the surfaces of the parts is decreased, and an ultrahigh vacuum can be realized in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sample moving device used in an analyzer or the like that performs analysis under ultra-high vacuum pressure.

Various analytical devices analyze the elemental state of the sample surface using the generated Auger electrons or photoelectrons by irradiating the sample surface with a narrowly focused electron beam or X-ray in a vacuum. Since it is necessary to change the position, a sample moving device that can mount and move the sample relative to the electron beam or XMK is essential.

In addition, in these analyzers, the residual gas in the vacuum chamber is
During analysis, in order to prevent adsorption to the sample surface, the pressure is low, that is, I
It is necessary to perform the analysis in a vacuum chamber with an ultra-high vacuum of 0-.Pa) or less. At this time, the ultra-high vacuum cannot be maintained unless the gas released from the walls of the vacuum chamber and the surface of the device inside the chamber is constantly evacuated using a vacuum exhaust system. That is, since there is a limit to the exhaust capacity of the vacuum exhaust system, it is necessary to reduce the amount of released gas. Therefore, the material used to construct the device is stainless steel, which releases less gas.

Only limited materials such as oxygen-free steel can be used.

In addition, while performing vacuum evacuation in order to quickly evacuate moisture adhering to the walls of the vacuum chamber and the surface of the equipment inside, which are the main components of the released gas, and to lower the pressure within the vacuum chamber in a short time, It is necessary to heat the entire vacuum chamber to 200C or higher for several hours and perform baking to forcibly release moisture from the surface.

On the other hand, in order to obtain smooth movement as a sample moving device,
If lubricant is used on guide surfaces, etc., a large amount of gas will be released from the lubricant over a long period of time, which will have a negative impact on the analysis.Furthermore, this gas will become the above-mentioned 6 emitted gas. Lubricants cannot be used.

FIG. 1 shows an example of a conventional sample moving device used in an Auger electron analyzer. The movable table 2 inside the vacuum chamber 1 is moved in two directions shown by arrows 4 and 5 by rotation introducers 3 and 13 that introduce rotational motion from the outside of the vacuum chamber 1 into the inside of the vacuum chamber 1. ing. Movement in the direction of the arrow 4 is achieved by rotating the rotation introducer 3 to rotate the shaft 6 in the vacuum chamber 1, and by rotating the screw 8 that is connected to the shaft 6 by a coupling 7 and supported by a guide 23. , the nut 9 is moved, and the moving table lO to which the nut 9 is attached is moved. The guide surface 11 of the movable table 10 utilizes sliding contact of the material Teflon. The spring 12 has a structure that always pushes the movable table 10 in one direction and eliminates backlash of the screw 8. Further, for movement in the direction of arrow 5, the direction of the rotational force of the rotation introducer 13 is changed by the bevel gear 14, and the moving table 2 is moved by the screw 15 and nut 16. Furthermore, the guide surface 17 of this movable table 2 is made of Teflon. A spline 18 is disposed in the middle of this power transmission system so as to be extendable and retractable in the four directions of arrows. This vacuum chamber 1 is equipped with a vacuum evacuation system 19 in addition to a sample moving device, and is constantly evacuated. Further, electrons generated by the upper electron gun 20 and narrowed to a diameter of 1 μm or less are irradiated onto the sample 21 on the moving table 2 in the direction of the arrow 24, and the electrons emitted from the sample 21 are analyzed. A container 22 is attached.

However, the above-described device has the following drawbacks.

11) Since the nuts and screws that move the moving platform utilize non-lubricated sliding contact, especially after baking, the coefficient of friction increases and galling occurs, making smooth movement impossible.

(2) If the sample moving device is driven four times when the 25-hour binding described in (1) above occurs, an excessive load torque will be applied to the rotating introducer and the rotating introducer will be damaged.

(3) Because Teflon is used as the material for the guide surface of the moving table, the baking temperature cannot be raised above 100°C, so it takes a long time to reach the specified pressure, and the exhaust gas has a large exhaust capacity. A system is necessary.

For the above-mentioned reasons, in analyzers equipped with such a sample moving stage, evacuation takes time, and moreover, there are many failures due to galling of the sample stage drive system.

The present invention has been made in view of the above points, and provides a sample moving device that eliminates the strain of the drive system and enables short evacuation time in an Auger analyzer such as the one described above. This is what we provide.

In order to achieve the above object, the present invention eliminates screws and gears, which are typical of sliding contacts, from the guide of the power transmission system of the sample moving table, the drive contact part, and the guide of the moving table, thereby reducing the coefficient of friction. By using only rolling contact without galling, and by using stainless steel for the components that can be baked at 200C or higher, the device can be used satisfactorily in an ultra-high vacuum.

Hereinafter, the present invention will be explained in detail with reference to Examples.
.

FIG. 2 is a diagram showing an embodiment in which the present invention is applied to an Auger electron analyzer. Two directions perpendicular to each other in the direction of arrow 31 and the direction of arrow 32 arranged in the vacuum chamber 30
The material 33 is moved in the direction. The vacuum chamber 30 is moved by a linear introducer 35 that introduces linear motion from the outside to the inside of the vacuum chamber 30.
A shaft 41 guided by a bearing 40 using internal rolling contact is moved in the direction of arrow 31. This shaft 41
The linear motion of the arrow 3 is transmitted to a moving table 38 having a rolling contact guide surface 48 of a stainless steel ball or the like.
It has a structure that allows it to move in one direction. This moving table 38 is
It is always pulled in one direction by a spring 39. Next arrow 3
Movement in direction 2 is achieved by the linear introducer 34 outside the vacuum chamber moving the shaft 37 inside the vacuum chamber 30 using the rolling contact of the bearing 36 for guidance in the direction of the arrow 31, and then by moving the lever 4.
2, the direction of movement is changed by 90 degrees using the shaft 50 as a fulcrum, and the rolling contact guide surface 49 mounted on the 1.66 platform 38
It has a structure that moves a moving table 43 having a handle. When moving the moving table in the direction of arrow 32, a bearing 45 attached to the tip of lever 42 is inserted into a long hole 44 extending in the direction of arrow 31 so as not to be affected by movement in the direction of arrow 31.
The movable table 43 has a structure in which it rolls into contact when moving in the direction of the arrow 31. All parts constituting this sample moving device are made of stainless steel. And moving platform 4
A sample 33 is placed on top of the sample 33, and is irradiated with electrons from an electron gun 46 from above, and Auger electrons emitted from the sample 33 enter an analyzer 47.

By having the above structure, the present invention provides (1)
Rolling contact is used to guide the moving platform and its power transmission system, and screws,
By eliminating the sliding contact caused by gears and replacing it with rolling contact, the coefficient of friction is reduced, and when driving the sample moving device in an ultra-high vacuum, there will be no failure due to galling.
It is possible to maintain accuracy for a long period of time, increasing the lifespan.

(2) All the parts that make up the sample moving device are made of stainless steel, making it possible to bake at temperatures above 200C, reducing the amount of gas released from the parts surface, and allowing the vacuum chamber to reach ultra-high vacuum in a short time. It has now reached .

As a result of the above, the pressure in the vacuum chamber can be brought to an ultra-high vacuum pressure in a short time, and a sample moving device that is free from curling and that moves smoothly and accurately can be obtained.

It goes without saying that in the present invention, if the moving table is made of non-magnetic stainless steel, a sample moving device used for a specific purpose can be realized.

Furthermore, in addition to the Auger electron analyzer used in the explanation of the above embodiments, the sample moving device of the present invention is effective in analyzers that analyze samples in ultra-high vacuum environments, such as the 880-person analyzer and the 8BM analyzer. Needless to say.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an Auger electron analyzer equipped with a conventional sample moving device, and FIG. 2 is a sectional view showing an example of an Auger electron analyzer equipped with a sample moving device according to the present invention. 1.30... Vacuum chamber, 3.13... Rotating introducer, End... Screw, 9... Nut, 12... Spring, 14...
・Bevel gear, 21.33...sample, 22.47...
Analyzer, 34°χ I section

Claims (1)

[Claims] A sample to be analyzed is mounted inside a vacuum chamber of an analyzer that maintains a pressure of less than I A sample moving device characterized in that rolling contact is used for the surface and the drive contact portion, and the material of the component parts of the moving table is stainless steel A.