JP2883110B2 - Microscope focusing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a focusing device for a microscope used for inspecting a large sample such as a wafer and a mask in the semiconductor industry and the like.

[Conventional technology]

The conventional microscope stage of this type has to be large and heavy in order to mount a sample such as a large wafer such as 6 inches, 8 inches, or 10 inches such as a wafer or a mask.

However, one of the conventional focusing devices of a microscope is, for example, as shown in FIG. 8, in which a stage 1 is cantilevered by a microscope main body 3 via a vertical drive mechanism 2 so that a heavy sample can be placed on the microscope. Does not have sufficient rigidity, for example, when the stage 1 is operated, the stage 1 is bent or vibrated and the objective optical system 4 is out of focus. Reference numeral 5 denotes an illumination light source, and reference numeral 6 denotes a mirror which bends the illumination light beam at a right angle and guides the same to a sample (not shown) on the stage 1 via a condenser lens 7.

Therefore, recently, as shown in FIG. 9, for example, a linear ball guide 9 is fitted to at least three columns 8 and the stage 1 is fixed thereon, and a rack and pinion mechanism is provided near the optical axis. There is an apparatus in which a vertical drive mechanism 10 for a stage 1 is provided to provide the stage 1 with rigidity and stability of vertical movement. For simplicity, as shown in FIG. 10, there is a type in which a rod 11 is fixed to the lower surface of the distal end portion of the stage 1 and is guided by a guide sleeve 12 so as to have a certain degree of rigidity.

[Problems to be solved by the invention]

However, the one shown in FIGS. 8 and 10 is different from the one shown in FIGS. 8 and 10 in that the vertical drive mechanism glue is displaced from the center of gravity of the stage 1 and there are only two guides. There was a problem that the stability was insufficient. On the other hand, the one shown in FIG. 9 can solve such a problem considerably, but it is difficult to adjust the parallelism of the three columns 8, and the length of the contact portion between the linear ball guide 9 and the column 8 is short. As a result, there has been a problem that the fall or shortage of the stroke is apt to occur, and the entire device is inevitably enlarged. In addition, there is a problem that the structure itself in which three separate linear ball guides 9 are fixed to the stage 1, which is a single plate, has poor strength.

The present invention has been made in view of the above problems, and has sufficient rigidity, vibration resistance and stability of up-and-down movement of a quasi-focus moving unit, and does not fall down.
It is an object of the present invention to provide a focusing device for a microscope that can take a sufficient stroke, make the entire device compact, and have sufficient strength.

[Means and Actions for Solving the Problems]

A focusing device for a microscope according to the present invention includes a stage having a hollow structure that supports a stage or an objective lens and is driven up and down by a driving mechanism, and includes an outer surface of the stage and an outer frame fixed to a microscope body surrounding the stage. By having at least three upper and lower guide mechanisms provided therebetween, the member for supporting the stage or the objective lens is formed of a single base having an integral structure, and there are at least three guide mechanisms for guiding the same. The component is integrated with the base.

The focusing device for a microscope according to the present invention is provided with a hole for introducing an illumination light beam on a side wall of the hollow structure table, and the illumination light beam is bent by a mirror in the table so as to be guided to a sample. is there.

In addition, the focusing device for a microscope according to the present invention is configured such that the base, the driving mechanism, the outer frame, and the up-and-down guide mechanism are detachably fixed to the microscope main body as one unit, so that it can be mounted on another microscope or another device. It is made to be applicable.

〔Example〕

Hereinafter, the present invention will be described in detail with the same reference numerals given to the same members as those of the above-described conventional example based on the illustrated embodiment.

FIG. 1 is a horizontal sectional view of a first embodiment of the present invention, FIG.
The figure is a vertical sectional view thereof. In the figure, reference numeral 10 denotes a rectangular tube-shaped outer frame fixed to a microscope body (not shown).
Holes 11 for introducing the illumination light beam
Is provided. Numeral 12 is located in the outer frame 10 and the stage 1 is fixed to the top surface thereof, and the outer surface is provided via four vertical roller guides 13 provided between the outer frame 10 and the four corners. A base having a hollow structure supported by the frame 10 so as to be vertically slidable, and a hole 14 for introducing an illumination light beam and a hole 15 through which a drive shaft or the like described later penetrates are provided on the side wall thereof (the (See FIG. 3). 16 is a vertical rack fixed to the base 12 so that the teeth are located in the base 12, and 17 is an outer frame 10
Between the two side walls so as to be rotatable and a rack 16
And a drive shaft to which a pinion 18 meshing with the drive shaft is fixed, and these constitute a vertical drive mechanism. The position of the teeth of the rack 16 is selected as close as possible to the center of the stage 1.

19 is a column supporting the mirror 6 at a 45 ° angle, and 20 is a column.
A support cylinder fixed to the top of 19 and provided with a hole 21 for introducing illumination light to the mirror 6 on the side wall, 22 is a condenser lens fixed to the top of the support cylinder 20, and 23 is a side wall of the outer frame 10 A diaphragm adjustment lever for adjusting the diaphragm in the condenser lens 22 which is pivotally supported at the tip and whose leading worm is engaged with the gear of the condenser lens. After being bent upward and condensed by the condenser lens 22, the light is guided to a sample (not shown).

Also, the table 12, the vertical drive mechanism, the outer frame 10, the roller guide 13
Are detachably fixed to the microscope body as one unit.

Since the present embodiment is configured as described above, the drive shaft 17
It is obvious that the table 12 is moved up and down through the pinion 18 and the rack 16 by rotating the stage 1, whereby the stage 1 is moved up and down and focusing is performed.

In this embodiment, the member for supporting the stage 1 is composed of a single base 12 having an integral structure, and there are four guide mechanisms for guiding the same. Since it is integrated with the stage 1, the rigidity and vibration resistance, the stability of the vertical movement of the stage 1 are sufficient, and the strength is also sufficient. Further, since the vertical drive mechanism is located near the center of the stage 1, the stability of the vertical movement of the stage 1 is further increased. Since the number of parts is small, assembling becomes easy, and accuracy is improved by performing various processes on one member. Further, since the components of the guide mechanism extend over the entire length of the table 12 in the vertical direction, no fall occurs, a sufficient stroke can be obtained, and the entire apparatus can be made compact.

Further, in the present embodiment, the base 12, the vertical drive mechanism, the outer frame 10
In addition, since the vertical guide mechanism is detachably fixed to the microscope main body as one unit, it can be applied to other microscopes and other devices. FIG. 4 is a perspective view of a modification of the table 12 of the first embodiment, which has a U-shaped horizontal section and three roller guides 13. this is,
This is effective when the strength is not so important, when the vertical drive mechanism installed inside is large, or when the light flux is large.

FIG. 5 is a perspective view of another modification of the table 12, which has a structure corresponding to a particularly large stage 1. As is apparent from the figure, the vertical drive mechanism is located near the optical axis (near the center of gravity). )
The horizontal section of the table 12 is substantially A-shaped.

FIG. 6 is a horizontal sectional view of the second embodiment, and FIG. 7 is a vertical sectional view thereof. This is because the objective lens 24 is hinged to the bottom wall of the base 12 and the outer frame 10 is inserted through the hole 15 of the base 12.
Alice Rider 26 on female ant 25 laid between both side walls of
Aris rider 26, an excitation filter 27, a multi-function body 29 having a half mirror 28 and another multi-function body 29 ', 29''having a dichroic mirror, etc. are detachably attached from the outside to be selectable, Further, the vertical drive mechanism as described above is provided outside the table 12.

In the case of the present embodiment, focusing is performed by vertically moving the objective lens 24, and illumination is epi-illumination. or,
Although the vertical drive mechanism is outside the table 12, the objective lens 24 is not heavy like the stage 1, so that the stability of the vertical movement of the objective lens 24 is not impaired.

〔The invention's effect〕

As described above, the focusing device for a microscope according to the present invention has sufficient rigidity, vibration resistance and stability of up-and-down movement of the focusing moving unit, does not fall down, has a sufficient stroke, and has a compact overall device. And has an important practical advantage that the strength is sufficient.

[Brief description of the drawings]

1 is a vertical sectional view of a first embodiment of a focusing device for a microscope according to the present invention, FIG. 2 is a horizontal sectional view thereof, FIG. 3 is a perspective view of a table of the first embodiment, FIGS. 5 is a perspective view of a modification of the table of the first embodiment and another modification thereof, FIG. 6 is a horizontal sectional view of the second embodiment, FIG. 7 is a vertical sectional view thereof, and FIG. FIGS. 9 and 10 are schematic cross-sectional views of a main part of another conventional example. 1 ... stage, 5 ... light source, 6 ... mirror, 10 ...
... Outer frame, 11, 14, 15, 21 ... Hole, 12 ... Stand, 13 ... Roller guide, 16 ... Rack, 17 ... Drive shaft, 18 ... Pinion, 19 ... Support, 20 ... Supporting cylinder, 22 ... condenser lens, 23 ... aperture adjustment lever, 24 ... objective lens, 25 ...
Female ant, 26 Alice rider, 27 Excitation filter, 28 Half mirror, 29, 29 ', 29 "... Composite function.

Claims (3)

(57) [Claims] 1. A stage having a hollow structure which supports a stage or an objective lens and is driven up and down by a driving mechanism, and is provided between an outer surface of the stage and an outer frame fixed to a microscope body surrounding the stage. A focusing device for a microscope, comprising at least three vertical guide mechanisms. 2. The hollow-structured table is provided with a hole for introducing an illumination light beam on a side wall thereof, and the illumination light beam is bent by a mirror in the table and guided to a sample. 1) A microscope focusing device according to 1). 3. The focusing device according to claim 1, wherein the base, the driving mechanism, the outer frame, and the vertical guide mechanism are detachably fixed to the microscope body as one unit.