JP2001084939A - Sample holder of scanning electron microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sample holder that is so structured that a sample table is easy to mount and the sample table is less likely to come off or slip. SOLUTION: This holder has slots 6 for receiving both facing end parts of a sample table 2 in parallel with a rotation axis and thereby holding the sample table when a sample is fixed and rotated, and has a plate spring 4 for fixing the sample table 2 by pressing it against the slots 6. A maximum distance L1 between the slots 6 is set larger than a width L2 of the sample table 2, and a minimum distance L3 between the slots 6 is set smaller than a width L2 of the sample table.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sample holder for a scanning electron microscope.

[0002]

2. Description of the Related Art In a conventional scanning electron microscope, not only observation of a scanning electron microscope image but also observation of a reflection electron image, composition analysis, and the like can be added to a large number of analytical detectors.
A large space is provided under the mirror body.

On the other hand, when the sample to be observed is put into and taken out of the mirror body, if this wide space is entirely exposed to the atmosphere, adsorption of moisture and the like in the air occurs inside the mirror body, and it takes time for evacuation. In addition, there is a problem that the quality of vacuum is reduced. In order to avoid this, a so-called side-entry system in which a preliminary exhaust chamber is provided on the side surface of the mirror body and a sample is introduced into the lens barrel after preliminary exhaust has been performed is used in many scanning electron microscopes.

In recent years, a scanning electron microscope of a type having an electron gun of a field emission type as an electron source has also been generally used. The in-lens type to be introduced is particularly suitable for high-resolution image observation, and is used for many sample observations.

In such an in-lens type scanning electron microscope, conventionally, as shown in FIG.
Is attached to the sample stage 102 in advance, and the sample stage 10
2 was held between the sample mounting portion by a set of movable grooved metal fittings 104, and further, screws 105 were screwed and fixed.

As another example of a holder using fixing means, there is a method of fixing a sample using a pressure difference between the inside and the outside of a sample holder, as proposed in Japanese Patent Application Laid-Open No. Hei 7-130316. 8).

[0007]

However, when a conventional sample holder as shown in FIG. 7 supports a sample stage on which a sample is mounted, first, a movable set of grooved metal fittings 104 is moved. After the distance between the fittings is maximized (FIG. 7 (b)), the sample stage 102 is placed between a pair of fittings (FIG. 7 (c)), and the fitting 104 is moved in the direction of the sample stage to move the sample stage. It was necessary to simultaneously perform a series of operations of sandwiching the groove 102 in the groove of the metal fitting 104 and further fixing it with screws (FIG. 7D). In addition, depending on the height of the sample, multiple sets of grooves are provided on the grooved metal fitting to adjust the height of the sample, an appropriate groove is selected according to the sample, and both heights of one set of metal fittings are adjusted. Had to be pinched.

For this reason, in these operations, the operations are apt to vary, and when the sample holder on which the sample stage is mounted is rotated and inserted into the lens barrel, the sample stage may fall off, or a set of samples may be lost. In some cases, the height of the groove of the bracket was shifted. When the sample stage is dropped, the inside of the lens barrel must be opened to the atmosphere in order to remove the sample stage. This not only makes the dropped sample unobservable, but also requires time and effort to damage the prepared sample, as well as cleaning the sample to remove debris. Damage, such as a decrease in Further, if the heights of the grooves of both metal fittings are shifted, focusing may not be achieved depending on the observation place of one sample.

A sample holder for fixing a sample by using a pressure difference between the inside and the outside of the sample holder as shown in FIG. 8 may be unstable because the sample stage is not sufficiently fixed at atmospheric pressure. there were.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a sample holder having a structure in which a sample table can be easily mounted and the sample table is not easily dropped or displaced. And

[0011]

Means for Solving the Problems The present invention has been made by intensive studies in order to solve the above-mentioned problems.
This is the configuration described below.

That is, the present invention relates to a sample holder for a scanning electron microscope which rotates while fixing a sample, at least one set for holding opposite ends of the sample table and holding the sample table in a direction parallel to the rotation axis. Having a fixed groove, and having means for pressing and fixing the sample table accommodated in the groove against the sample holder, the maximum distance between the pair of grooves is larger than the width of the sample table, The minimum distance between the grooves is smaller than the width of the sample stage.

Further, the sample holder of the present invention is characterized in that it has a plurality of grooves for holding the sample stage.

The sample holder according to the present invention is characterized in that at least an electron irradiation range is open.

Further, the sample holder of the present invention is characterized in that it has a scale on the electron beam scanning surface side.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a view showing an example of a sample holder of the present invention. FIG. 1 (a) is a plan view, FIG. 1 (b) is a perspective view,
FIG. 1C is a sectional view taken along the line AA ′ of FIG. 1B, and FIG.
FIG. 2 is a sectional view taken along the line BB ′ of FIG. FIG. 1 (a)
1 shows a state before the sample stage is attached to the holder, and FIG.
(B)-(d) have shown the state which attached the sample stand to the holder.

In FIG. 1, 1 is a sample, 2 is a sample stage on which the sample 1 is attached, 3 is a sample holder body for holding the sample stage 2 and inserted into the scanning electron microscope, 4 is a leaf spring, 6
Is a set of grooves into which the sample table 2 is inserted. Reference numeral 9 denotes an opening of a sample holder for allowing an electron beam to be incident on the sample 1, both a sample insertion portion 20 for inserting the sample stage 2 into the holder and a sample observation position 19 for allowing an electron beam to be incident on the sample. It is open across. D1 is the height of the groove 6, d
2 is the thickness of the sample table 2, L1 is the maximum distance between a pair of grooves 6,
L2 is the width of the sample table 2 and L3 is the minimum distance between a pair of grooves 6.

FIG. 6 is a schematic view showing a state where the sample holder of FIG. 1 is inserted into the holder. 6, 10 and 11 are vacuum valves, 12 is a preliminary exhaust chamber, 13 is a sample chamber, 14 is an objective lens, 15 is a secondary electron detector, 16 is an exhaust port of the preliminary exhaust chamber, and 17 is an exhaust of the sample chamber. The mouth 18 is an electron beam.

The sample holder of the present invention shown in FIG. 1 is inserted into a sample chamber of a scanning electron microscope while rotating while fixing the sample, and a pair of the sample holders are opposed to each other in a direction parallel to the rotation axis. And has a structure for holding the sample stage 2 by accommodating the opposite ends of the sample stage 2 in the set of grooves 6.

The distances L1 and L3 of each part between the set of grooves 6
And the width L2 of the sample table 2 are designed such that L1>L2> L3, and further, the height d1 of the groove 6 and the thickness d2 of the sample table 2
Are designed such that d1 ≧ d2.

A leaf spring 4 is provided below a portion where the sample table 2 is inserted.
Is pressed against the upper part of the groove 6 and fixed.

Therefore, when the sample table 2 is mounted on the sample holder, the sample table 2 on which the sample 1 has been adhered can be securely fixed by sliding the sample table 2 between the grooves 6. Further, the sample holder is moved to the sample chamber 13.
When the sample holder is rotated in the rotation direction of the sample holder to be introduced into the sample 1 (see FIG. 6), the sample 1 does not fall off. This is because the grooves 6 for holding the sample table 2 are formed directly fixed to the sample holder main body 3, the minimum distance L 3 between the grooves 6 does not change, and the widths L 2 and L 3 of the sample table 2 are changed. L
This is because 2> L3. Further, since the sample table 2 is pressed against the groove 6 by the leaf spring 4, the sample table 2 is fixed, and image observation can be performed stably.

In the example shown in FIG. 1, a leaf spring 4 is provided below the portion where the sample stage 2 is located, and
The leaf spring 5 is provided at the end of the groove as shown in FIG. 2, and when the sample table 2 is completely inserted into the groove 6, the specimen table 2 is held by the leaf spring 5 as shown in FIG. A method of fixing by pressing against the tip may be adopted. Further, a fixing claw may be provided in place of the leaf spring, and the sample table may be pressed against the sample holder with the claw, or a fixing set piece may be provided. Other than these, any means for pressing and fixing the sample table to the sample holder is not limited to these.

Further, since the sample 1 is inserted while confirming the cross-sectional shape of the groove 6, the height of the sample surface does not largely shift with respect to the height of the sample table 2, and thus the focus is adjusted depending on the position of the sample. Can be prevented from disappearing.

In the sample holder shown in FIG. 1, the opening 9 at the sample observation position 19 for irradiating the sample with electrons is open so as to cover at least the electron irradiation range. As a result, it is possible to observe a region that can be irradiated with primary electrons. Further, the opening 9 of the sample insertion section 20 only needs to open at least wider than the sample table 2. Although not provided in the present embodiment, a lid may be provided on the sample insertion section 20.

An opening may be provided on the back side of the electron irradiation surface of the holder, or the entire surface may be closed. Further, the back surface opening is not limited to a quadrangle, but may be a mesh shape as shown in FIGS. 3 to 5. By making the area of the rear opening smaller than the area of the sample stage, the sample stage 2 can be more reliably prevented from falling off. Further, by providing an opening on the back surface, even when observing a sample in which extra deposits are likely to be generated, it is possible to prevent dust or the like from adhering to the inside of the sample holder. Therefore, it is possible not only to prevent such dust from adhering to the sample, but also to prevent an obstacle to image observation due to scattering in the mirror body.

Further, by making the position and shape of the opening 9 at the sample observing position 19 of the holder substantially coincide with the electron irradiable range, the sample table 2 on which the sample 1 is loaded is introduced into the sample chamber 13 and the secondary electron image is obtained. Before observing, the observable position can be confirmed in advance. Further, since the opening 9 is not opened unnecessarily, the sample stage 2 from the opening 9 is opened.
It is also possible to prevent falling.

A scale may be provided near the opening 9 at the sample observation position 19. By providing the scale, when the sample holder 3 is inserted into the sample chamber 13, the observation position relative to the center position of the holder opening initially displayed can be clearly imaged before inserting the holder into the sample chamber. Become. Therefore, when the sample table 2 is inserted into the sample chamber 13 and the image is observed, the operation of moving the holder to the observation place becomes easy.

Next, a procedure for setting a sample using the sample holder of the present invention will be described.

(1) The sample 1 to be observed is placed at the sample observation position 19
Is cut into a size that can be accommodated in the opening 9 of FIG. For fixing to the sample stage 2, a carbon paste or the like generally used for a scanning electron microscope can be used. After fixing, leave the paste at room temperature until the paste dries or heat to dry.

(2) The sample table 2 is put into the holder from the sample table insertion section 20 of the sample holder 3 and moved to the sample observation position 19. A groove 6 is formed inside the holder at this position as shown in FIG. 1C, and the sample table 2 is slid along the groove 6 and inserted. By this operation, the sample stage 2
Is inserted into the groove 6, and at the same time, is pushed up from below by the leaf spring 4, pressed against the groove 6 and fixed.

(3) The sample stage and the sample are attached to the sample holder as described above, pre-evacuated in the pre-evacuation chamber 12, and then introduced into the lens barrel while rotating the sample holder to observe the SEM image.

Since the sample holder has the above-described structure, the sample can be inserted without causing a variation in operation, and damage due to breakage of the sample or stoppage of the apparatus can be prevented. .

In the above installation procedure, the holder having the structure shown in FIG. 1 has been described. However, as described above, the method of fixing the sample holder is not limited to this, and the groove 6 is not one set but a plurality of sets. May be.

[0036]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited to these examples, and each element within a range in which the object of the present invention is achieved. Also includes those that have undergone replacement or design changes.

(Embodiment 1) FIG. 1 is an explanation for explaining this embodiment. The sample holder of this embodiment is of a side entry type and is used for an in-lens type high-resolution scanning electron microscope as shown in FIG. FIG. 1A is a plan view, and FIG.
1 is a perspective view, FIG. 1C is a cross-sectional view taken along the line AA ′ of FIG.
FIG. 1D is a cross-sectional view taken along the line BB ′ of FIG. FIG.
, 1 is a sample, 2 is a sample stage, 3 is a sample holder main body, 4 is a leaf spring, and 6 is a set of grooves for inserting and holding the sample stage 2.

In this embodiment, the thickness d1 of the groove 6 is 1.
2 mm, the thickness d2 of the sample stage 2 is 1.1 mm, and a set of grooves 6
The maximum distance L1 between them is 7.0 mm, the width L2 of the sample table 2 is 6.9 mm, and the minimum distance L3 between a pair of grooves 6 is 5.5 mm.
And

When mounting the sample stage 2 on the sample holder, the sample stage 2 is inserted into the holder through the opening 20 of the sample insertion portion, and then the sample stage 2 is slid along the groove 6 toward the observation position 19. And inserted. At this time, since the sample table 2 was pushed up from below by the leaf spring 4, it was pressed above the groove 6 and was firmly fixed.

Thereafter, the sample holder 3 was inserted into the preliminary exhaust chamber 12 to perform preliminary exhaust, and the sample holder 3 was inserted into the sample chamber 13 while rotating (see FIG. 6). After that, the sample holder was rotated and inclined to observe the sample.

In these processes, when the fixing is performed by the method of the present embodiment, unlike the conventional sample holder in which the fixing bracket is movable, the sample holder is simply sandwiched by the bracket and the operation of simultaneously tightening the screws is not performed. The operation of inserting the sample stage 2 into the groove 6 could easily fix the sample stage. In addition, the relationship between the minimum distance L3 between the pair of grooves 6 and the width L2 of the sample table is L2> L3, and the sample table is fixed by the plate spring 4 as a fixing means.
Accidents such as damage to the sample due to dropping of the sample stage were prevented.

(Embodiment 2) FIG. 2 is an explanatory view for explaining this embodiment. The sample holder of this embodiment is the same as in the first embodiment.
It is for side entry type, high resolution scanning electron microscope of in-lens type. 2A is a plan view showing a state before the sample stage is attached to the holder, FIG. 2B is a plan view showing a state where the sample stage is attached to the holder, and FIG. 2C is FIG. 2B. It is CC 'sectional drawing of.

In FIG. 2, 1 is a sample, 2 is a sample stage, 3
Is a sample holder main body, and 6 is a groove for inserting and holding the sample table 2, and three sets are provided in this embodiment. Reference numeral 5 denotes a leaf spring for fixing the sample stage 2, which presses and fixes the sample stage 2 against the tip of the holder.

In this embodiment, the thickness d1 of the groove 6 is 1.
2 mm, the thickness d2 of the sample stage 2 is 1.1 mm, and a set of grooves 6
The maximum distance L1 between them is 7.0 mm, the width L2 of the sample table 2 is 6.9 mm, and the minimum distance L3 between a pair of grooves 6 is 5.5 mm.
And

When mounting the sample stage 2 on the sample holder, the sample stage 2 was inserted into the holder from the sample insertion section 20, and the sample stage was slid along the groove 6 toward the sample observation position 19. By this operation, the sample table was pressed and fixed to the tip of the sample holder by the leaf spring 5.

By fixing in this manner, unlike the conventional sample holder in which the fixing bracket can be moved, the groove 6 cannot be moved, so that the sample can be inserted without causing a variation in the operation as in the first embodiment. And the effect of preventing damage due to breakage of the sample or stoppage of the device was obtained. Further, by providing three sets of the grooves 6, samples of various thicknesses, from a thin sample to a thick sample, could be adhered to a sample table of the same thickness and observed.

(Embodiment 3) FIG. 3 is an explanatory diagram for explaining the present embodiment. 3A is a plan view showing a state before the sample stage is attached to the holder, FIG. 3B is a plan view showing a state where the sample stage is attached to the holder, and FIG. 3C is FIG. 3B.
It is DD 'sectional drawing of.

In FIG. 3, 1 is a sample, 2 is a sample stage, 3
Is a sample holder main body, and 6 is a groove for inserting and holding the sample table 2, and three sets are provided in this embodiment. Reference numeral 5 denotes a leaf spring for fixing the sample stage 2, which presses and fixes the sample stage 2 against the tip of the holder.

In the present embodiment, the mesh 7 is provided on the back surface, particularly in order to provide an opening on the back surface of the electronic scanning surface.

In this embodiment, the thickness d1 of the groove 6 is 1.
1 mm, the thickness d2 of the sample stage 2 is 1.0 mm, and a set of grooves 6
The maximum distance L1 between them is 7.2 mm, the width L2 of the sample table 2 is 7.1 mm, and the minimum distance L3 between a pair of grooves 6 is 5.5 mm.
And

When mounting the sample table 2 on the sample holder, the sample table 2 was inserted into the holder from the sample insertion section 20 and the sample table 2 was slid along the groove 6 toward the sample observation position 19 and moved. . By this operation, the sample table was pressed and fixed to the tip of the sample holder by the leaf spring 5.

When fixed by this method, similar to the second embodiment,
In addition to the effect of preventing accidents such as dropping of the sample stage and damage to the sample, the mesh-shaped bottom prevents dust from accumulating on the bottom of the sample holder and, consequently, rotates the sample holder. The effect of preventing dust from sometimes falling into the lens barrel and obstructing observation of the sample was obtained.

(Embodiment 4) FIG. 4 is an explanatory diagram for explaining this embodiment. FIG. 4A is a plan view showing a state where the sample table is attached to the holder, and FIG. 4B is a view taken along the line EE ′ in FIG.
It is sectional drawing.

In this embodiment, when the bottom surface of the sample holder of the third embodiment is changed to a stripe shape as shown in FIG. 4, the same effect as that of the third embodiment is obtained.

(Embodiment 5) FIG. 5 is an explanatory diagram for explaining this embodiment. FIG. 5A is a plan view of the sample surface side showing a state where the sample stage is attached to the holder, and FIG.
FIG. 5A is a back view, and FIG. 5C is FF ′ of FIG.
It is sectional drawing.

In FIG. 5, 1 is a sample, 2 is a sample stage, 3
Is a sample holder main body, and 6 is a groove for inserting and holding the sample table 2, and three sets are provided in this embodiment. Reference numeral 5 denotes a leaf spring for fixing the sample stage 2, which presses and fixes the sample stage 2 against the tip of the holder.

In this embodiment, in order to provide an opening on the back surface of the electronic scanning surface, a mesh 7 is provided on the back surface, and a scale 8 is provided on the surface of the sample holder on the side of the sample observation position.
Further, the opening 9 on the sample observation position 19 side of the sample holder is matched with the maximum electron irradiation range of the scanning electron microscope.

In this embodiment, the thickness d1 of the groove 6 is 1.
0 mm, the thickness d2 of the sample stage 2 is 0.9 mm, and a set of grooves 6
The maximum distance L1 between them is 6.2 mm, the width L2 of the sample table 2 is 6.1 mm, and the minimum distance L3 between a pair of grooves 6 is 4.5 mm.
And

When mounting the sample table 2 on the sample holder, the sample table 2 was inserted into the holder from the sample insertion section 20, and the sample table 2 was slid along the groove 6 toward the sample observation position 19. . By this operation, the sample table was pressed and fixed to the tip of the sample holder by the leaf spring 5.

In this sample holder, not only the effect of the fourth embodiment is obtained, but also the maximum electron irradiation range and the opening 9 on the sample observation position 19 side of the sample holder coincide with each other. When the sample was settled, an indication was obtained that the entire area of the sample could be observed. That is, in the past, the sample was placed on almost the entire region of the sample stage, and the sample surface at the end of the sample stage could not be observed. However, the sample holder of the present embodiment solved these problems. .

[0061]

According to the sample holder of the scanning electron microscope of the present invention, the opposite ends of the sample stage are accommodated in a direction parallel to the rotation axis in the sample holder of the scanning electron microscope which fixes and rotates the sample. And at least one set of fixed grooves for holding the sample stage by holding the sample stage against the sample holder. Since the distance is larger than the width of the sample table and the minimum distance between the grooves is smaller than the width of the sample table, it is possible to prevent the sample from dropping into the preliminary exhaust chamber and the sample chamber due to an erroneous operation, being damaged, and being lost. In addition, the operability of the scanning electron microscope when exchanging samples can be improved.

By providing a plurality of grooves for holding the sample stage, samples having different thicknesses can be observed with the same sample holder.

In addition, since at least the electron irradiation range is open, it is possible to observe all the regions where primary electrons can be irradiated.

Further, by providing a scale on the electron beam scanning surface side, when the sample holder is inserted into the sample chamber, the relative observation position with respect to the center position of the holder opening initially displayed is set in the sample chamber. Can be clearly imaged before insertion, and the effect of facilitating movement to the observation location can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an embodiment and a first embodiment of the present invention.

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

FIG. 3 is a schematic diagram illustrating a third embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a fourth embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating a fifth embodiment of the present invention.

FIG. 6 is a schematic diagram showing a state when the sample holder of the present invention is introduced into a side entry type in-lens scanning electron microscope.

FIG. 7 is a schematic diagram illustrating a conventional technique.

FIG. 8 is a schematic view of a sample holder disclosed in JP-A-7-30316.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 101 Sample 2, 102 Sample stand 3, 103 Sample holder main body 4, 5 Leaf spring 6 Groove 7 Mesh 8 Scale 9 Sample stage opening 10, 11, Vacuum valve 12 Preliminary exhaust chamber 13 Sample chamber 14 Objective lens 15 Secondary electron Detector 16 Exhaust port of preliminary exhaust chamber 17 Exhaust port of sample chamber 18 Electron beam 19 Opening of sample observation position 20 Opening of sample insertion section 104 Metal fitting with groove 105 Screw d1 Height (thickness) of groove d2 Sample table Thickness L1 Maximum distance between a pair of grooves L2 Width of sample stage L3 Minimum distance between a pair of grooves

Claims (4)

[Claims] 1. A sample holder for a scanning electron microscope that rotates while fixing a sample, wherein at least one set of fixed holders that hold opposite ends of the sample stage and hold the sample stage in a direction parallel to the rotation axis. Having a groove, and having means for pressing and fixing the sample table housed in the groove to the sample holder, the maximum distance between the pair of grooves is larger than the width of the sample table, A sample holder for a scanning electron microscope, wherein the minimum distance is smaller than the width of the sample stage. 2. The sample holder for a scanning electron microscope according to claim 1, comprising a plurality of sets for holding the sample stage. 3. The sample holder for a scanning electron microscope according to claim 1, wherein at least an electron irradiation range is open. 4. The sample holder for a scanning electron microscope according to claim 1, wherein a scale is provided on an electron beam scanning surface side.