JPS5831404Y2 - Fine movement device for stage up/down, left/right tilt, and front/back tilt - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stage fine movement device that finely moves the stage of a mask aligner, a microscope, etc. used for fine bump processing of high-density integrated circuits, up and down and inclining with high precision.

Conventional fine-movement devices of this type apply driving force by directly pushing the stage or an arm protruding from the stage using a precision screw such as a micrometer head to finely move the stage up and down or in incline. Ta.

Figure 1 shows an example of such a conventional fine movement device.
is the stage, 2 is the disc spring, 3 is the base, 4 is the ball, 5
is a micrometer head.

The stage 1 is suspended and supported by a base 3 by a disc spring 2, and the stage 1 is suspended by pushing the periphery of the stage 1 with a micrometer head 5 via a ball 4.
is slightly moved up and down and tilted.

In the case of such conventional devices, the accuracy of the drive mechanism such as the micrometer head directly corresponds to the fine movement accuracy of the stage.

Therefore, by pressing the stage in one direction with a spring, etc.
Even if methods are taken to reduce play and backlash as much as possible, the stable fine movement accuracy is on the order of 0.5 to 1 μm, and the limit is to obtain a resolution on the order of 0.1 to 0.2 μm. Ta.

The present invention holds the fine movement stage against the base with a spring,
A device that drives the stage via a drive spring having a spring constant much smaller than the spring constant of the spring, and by controlling a large amount of deformation of the drive spring, it is possible to control slight movements of the stage. The purpose is to significantly improve the fine movement accuracy of the stage up and down, left and right tilt, and front and back tilt.

This will be explained in detail below with reference to the drawings. FIG. 2 shows an embodiment of the present invention.

In the figure, 6 is a stage, 7 is a base, 8 is a disc spring, 9 is a drive spring, 10 is a spring seat, 11 is a ball, 12 is a plate, 1
3 is a screw.

The stage 6 is suspended and supported on the upper part of the base 7 by a disc spring 8, and the lower surface of the stage 6 has a
One end of a coiled drive spring 9 is attached, and the other end of the drive spring 9 is attached to a screw 1 which is screwed vertically through a plate 12 at the bottom of the base 7 via a spring seat 10 and a ball 11.
It is set to be pressed at 3.

The drive springs 9 are attached to three to four locations on the lower surface of the stage 6, and by adjusting the amount of rotation of each screw 13, the drive springs 9 are
, thereby applying a stage driving force to the point at which the drive spring of the stage 6 is attached.

When the amount of deformation of each drive spring 9 is changed, the force acting on the point at which each drive spring is attached to the stage 6 changes, the disc spring 8 is deflected unevenly, and the inclination angle of the stage 6 is changed.

Moreover, if each drive spring 9 is deformed by the same amount, the stage 6 will move in the vertical direction.

At this time, the ratio of the displacement of the drive spring mounting point of the stage 6 to the amount of deformation of the drive spring 9 is equal to the ratio of the spring constant of the drive spring 9 to the spring constant of the disc spring 8.

Now, the spring constant of the drive spring 9 is much smaller than the spring constant of the disc spring 8.

Therefore, against large deformation of the drive spring 9, the disc spring 8
is only slightly deformed, and by adjusting the amount of deformation of the drive spring 9, it is possible to obtain a slight movement of the stage 6 that is reduced by a ratio corresponding to the spring constant ratio of the drive spring 9 and the disc spring 8.

In the embodiment shown in FIG. 2, the drive spring is driven by the rotation of the screw, but the rotation of the screw may be driven by a motor, or the drive spring can be driven by electromagnetic force, It may be driven by gas pressure or liquid pressure.

According to the present invention, as explained above, the stage is driven via a driving spring having a much smaller spring constant than the spring provided to hold the stage against the support base. The stage can be finely adjusted in response to large displacements of the drive spring, and the fine movement accuracy of the stage in the vertical direction and inclination is excellent. 0.
Fine movement accuracy on the order of 0.05~0.2μm, 0.01~0.
A resolution on the order of 0.05 μm can be obtained relatively easily.

[Brief explanation of drawings]

FIG. 1 shows an example of a conventional stage fine movement device, and FIG. 2 shows an embodiment of a stage fine movement device of the present invention, which is tilted vertically, horizontally, and tilted back and forth. 1.6...Stage, 2,8...Disc spring, 3,7...Base, 4,11...
Ball, 5...Micrometer head, 9...
... Drive spring, 10 ... Spring seat, 12 ...
...Plate, 13...Screw.

Claims (2)

[Scope of utility model registration request] (1) Of the 6 types of fine movements that can be given to the stage: 9 rotations left and right, 9 front and back tilts, up and down, 7 tilts left and right, 9 rotations, the stage has 3 degrees of freedom compared to the basic one: 9 rotations left and right, 9 tilts left and right.
The stage can be elastically deformed only in the direction in which the fine degree of freedom is desired, and the amount of deformation in other directions is negligible, so that the stage can be regarded as a fine movement in the degree of freedom. The stage is held against the base body by a non-deformable spring, and a driving force is applied to the stage through a driving spring having a spring constant much smaller than the spring constant in the direction of the spring to slightly move the stage. In addition, depending on the amount of drive of the drive spring,
A device for finely moving a stage in vertical, horizontal, and longitudinal inclinations, characterized in that the stage is configured to control vertical and inclining fine movements of the stage. (2) The stage is suspended from the base by a disc spring so that the stage can only tilt and move up and down within the range of elastic deformation of the disc spring, and the periphery of the stage is far away from the disc spring. The stage according to Claim 1 of the Utility Model Registration Claim, characterized in that the stage is pushed through a coil-shaped drive spring with a small spring constant, and the inclination and vertical fine movement of the stage are controlled by the amount of drive of the drive spring. Vertical, horizontal and horizontal tilting, and longitudinally tilting fine movement device.