JPS60167245A - Sample holding device - Google Patents

Abstract

PURPOSE:To automatically hold a sample according to a change of pressure in a vacuum by positioning the sample while holding a wafer end face by a displacement means including a metal bellows or the like when holding the sample such as a wafer or the like in a vacuum. CONSTITUTION:When observing a smaple 4 such as a wafer or the like by a scanning type electron microscope or the like, the wafer 4 staying in the air is placed on a sample stand 1 while being introduced into a vacuum to be observed it in the vacuum. Thereby, the wafer 4 is placed on a base stand 1 provided with supporting members 3, on which the wafer 4 is placed, and holding members 2 holding the end face of the wafer 4 while enabling the end face of the wafer 4 to be supported by a displacement means 6 displacing a holder 7 by a differential pressure between the inside and outside. Accordingly, the displacement means 6 does not operate at the atmospheric pressure while holding the wafer 4 end face in the vacuum and making the wafer 4 to slide on the supporting member 3 due to a change of the vacuum pressure so as to enable sure holding to be maintained automatically.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a sample holding device for a semiconductor substrate wafer (hereinafter referred to as a wafer), and particularly to a device suitable for holding a sample such as a wafer in a vacuum. This invention relates to a sample holding device.

[Background of the invention]

When observing a sample such as a wafer with a scanning electron microscope or an electron beam lithography device, or when drawing a ray beam on the surface of a sample such as a wafer, the sample such as a wafer in the atmosphere must be mounted on a sample stage. A method is adopted in which this is introduced into a vacuum and a sample sample of a wafer or the like is inspected or drawn under vacuum.

For example, when holding a wafer, a conventional sample holding device of this type has a plate fixed to the sample holding table, and a part of the wafer's circumference cut out in a straight line (this (This part is called the orientation flat)
The wafer is held by pressing the end surface of the wafer and pressing the upper surface of the outer periphery of the wafer with a spring or the like against a support that supports the outer periphery of the wafer and is fixed to the sample holding table. Ta.

However, in the conventional sample holding device described above, since the setting for holding the sample is done manually using a bottle set, etc., there is a high probability that dust will adhere to the sample, and the end surface or upper part of the wafer may be The wafer is held in place by a spring, etc. Furthermore, it has the disadvantage that the wafer cannot be positioned accurately.

[Purpose of the invention]

An object of the present invention is to provide a sample holding device that can accurately position a sample without damaging the sample.

[Summary of the invention]

The present invention provides a sample holding device that holds a sample such as a wafer in a vacuum, including a support member fixed to a base, and a plurality of support members fixed to the base and holding the end surface of the sample placed on the support member. A holding member, a plurality of holding members that hold the end face of the sample placed on the support member, and a holder at the tip for holding the end face of the sample placed on the support member together with the holding member, and the surrounding pressure is reduced. and means for displacing due to change, and the displacing means is characterized in that when the surrounding pressure changes from atmospheric pressure to vacuum pressure, the displacing means displaces to a position where the holder at the tip presses against the end surface of the sample. It is.

[Embodiments of the invention]

Embodiments of the present invention will be celebrated based on the drawings. FIG. 1 shows the configuration of an example of the sample holding device according to the present invention. In the figure, 1 is a base υ, and Ueno-4 as a sample is placed on the base 1. A supporting member 3 to be placed is fixedly installed 9, and a holding member 2 for holding the end face of the sea urchin/4 is fixed.
is permanently installed.

Further, a displacement means (metal bellows in this embodiment) 6 is fixedly mounted on the base 1 and has a retainer 7 at its tip for retaining the end face of the wafer 4 placed on the support member 3 together with the retainer 2. There is. Gas or liquid is contained inside the metal bellows 6, and the metal bellows 6 displaces the holder 7 due to the pressure difference between the inside and outside of the metal bellows 6. Furthermore, 5 is a guide for regulating the direction of movement of the holder 7 when the metal bellows 6 is displaced due to a change in ambient pressure.

The operation of the sample holding device with the above configuration is shown in Figures 2 and 3.
This will be explained using figures. Figure 2 shows the state before operation, and Figure 3 shows the state before operation.
The figure shows the state after operation.

When the surrounding pressure is atmospheric pressure, the metal bellows 6 is in the state shown in FIG. By sliding the upper part of the wafer 4 and continuing to displace it in the elongation direction until the orientation flat part of the wafer 4 contacts the 202 holding members and is held by the 3 holding members 2 and the holder 7, the wafer 4 (
Figure 3).

In the experimental results of this example, a maximum deviation of 5 microns at the center of a 4-inch wafer and a deviation of 15 microns at the edge of the wafer was observed. The eccentricity of the holding member 2 and the holding body 7 used at this time was 1 micron at most.

According to this embodiment, in the Makabe chamber as described above,
It has the following features and effects.

(1) In a vacuum chamber, the above-mentioned holding device can automatically hold the wafer only by changing the pressure in the vacuum chamber.

(2) In paragraph 1 above, the pressure decrease gradually goes out of line +
-1 It is possible to statically and dynamically hold the wafer on the wafer.

(3) The holding force for holding the wafer is that the pressure inside the vacuum chamber changes repeatedly from atmospheric pressure to a certain arbitrary pressure, so the holding force exerted by the holding member in the holding device on the wafer end surface is approximately Moreover, the above-mentioned matters have a great effect on reproducibility.

FIG. 4 shows another embodiment of the present invention, which differs from FIG.
The Uenohe 4 is held in the holding position by pressing the orientation/station/flat end with a holding member to which the Uenohe 4 is fixed.

In this embodiment, the number of holding members 2 can be reduced compared to the embodiment shown in FIG.

It is possible to reduce misalignment of the wafer caused by eccentricity of the holding member 2 in the holding device.

Furthermore, according to this embodiment, the object to be held is not limited to Ueno, but also objects having a polygonal shape larger than a triangle can be reliably held in a vacuum by making the shape of the orientation flat press plate 8 correspond. It is possible to hold.

In FIG. 4, members given the same numbers as those in FIG. 1 indicate the same members, so a description thereof will be omitted here.

〔Effect of the invention〕

According to the present invention, a sample such as a wafer is placed in a vacuum chamber,
It can be held automatically and statically by changing the pressure in the chamber mentioned above, and has good reproducibility, so it is possible to accurately hold the sample in a predetermined position without damaging it. .

Incidentally, in the above embodiments, the holding of the wafer has been described in detail, but this is not limited to just the wafer, and the same holds true for, for example, plates or blocks of magnetic desks, audio desks, etc. Furthermore, although a metal bellows is used in the embodiment as the displacement means, the present invention is not limited to this, and an elastic body such as rubber may be used.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the configuration of an embodiment of the sample holding device according to the present invention, FIGS. 2 and 3 are main parts of the front view of the sample holding device shown in FIG. 3 shows the state before operation, FIG. 3 shows the state after operation, and FIG. 4 is a plan view showing the structure of another embodiment of the sample holding device according to the present invention. 1... Base, 2... Holding member, 3... Supporting member,
4... Wafer, 5... Guide, 6... Displacement means,
7...Holding body, Fig. 1 Fig. 2 Hard No. 3 No. 4 Fig. 1 656s

Claims (1)

[Claims] 1. In a sample holding device that holds a sample such as a wafer in a vacuum, a support member fixed to a base and an end face of the sample fixed to the base and placed on the support member are provided. A plurality of holding members to hold, a plurality of holding members to hold the end face of the sample placed on the supporting member, and a holder for holding the end face of the sample placed on the supporting member together with the holding members at the tip. and means for displacing due to changes in surrounding pressure, the displacing means displacing to a position where the holder at the tip presses against the end surface of the sample when the surrounding pressure changes from atmospheric pressure to vacuum pressure. holding device. 2. The sample holding device according to claim 1, wherein the displacement means is a metal bellows or an elastic material such as rubber filled with gas or liquid.