JP2000186753A - Direct acting mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high speed/high precision, and long life direct acting mechanism without a linear guide enabling highly precise minute turn about the θ axis of a holder base. SOLUTION: Plates 13 are mounted on individual ends of two drive rods 12a, 12b arranged in parallel penetrating a vacuum container 11. The individual plates are fixed to their own linear motors. The drive rods are attached to a holder base 17 in the vacuum container 11. The holder base 17 is attached rotatably on its surface plane by using a holding member. Rotating two drive rods in opposite directions rotates the holding base 17 minutely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motion mechanism,
In particular, the present invention relates to a linear motion mechanism for moving a processing target in a predetermined direction in a vacuum container.

[0002]

2. Description of the Related Art In laser annealing, an object to be processed is introduced into a vacuum container, the inside of the vacuum container is evacuated to a vacuum or low-pressure gas atmosphere, and laser light is applied to the object through a quartz window or the like provided in the vacuum container. This is a technique of irradiating light to anneal a processing target object. In order to perform such laser annealing over a wide range of the surface of the object, a means for moving the object in the vacuum vessel is essential.

Conventionally, there has been a linear motion mechanism for realizing the above-described movement of the workpiece. A conventional linear motion mechanism includes a holder for holding a workpiece, which is held by two linear guides so as to be movable in one axis direction,
One end is fixed to the holding table, and the other end is provided with a drive shaft led out of the vacuum vessel, and a bellows for keeping airtight between the drive shaft and the vacuum vessel.

In the conventional linear motion mechanism, the holding table can be moved in the direction along the linear guide by driving the drive shaft. That is, the workpiece held by the holding table can be moved in the direction along the linear guide by moving the holding table. This allows
A wide range of processing of an object to be processed becomes possible.

By the way, in order to stably perform laser annealing, it may be necessary to heat the workpiece. To cope with such a case, a heater is embedded in the holding base of the conventional linear motion mechanism.

[0006]

However, in the conventional linear motion mechanism, when the holding table is heated using a heater, thermal distortion occurs in the holding table and the linear guide, and the durability and reliability of the holding table are increased. Has a serious adverse effect on sex.

Further, there is another problem that one or both of the holding table and the linear guide are shaved due to sliding of the holding table and the linear guide, and wear debris is generated, so that the inside of the vacuum vessel cannot be maintained in a clean atmosphere.

Furthermore, the conventional linear motion mechanism may incorporate a rotation mechanism for minutely rotating the holding table (rotation about an axis parallel to an axis perpendicular to the surface (hereinafter referred to as an θ axis)). There is a problem that a rotation mechanism installed outside the vacuum vessel cannot realize high-precision rotation control.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a linear motion mechanism which does not have a linear guide, has high speed and high accuracy, has a long service life, and is capable of minute rotation about the θ axis of a holding table with high accuracy. .

[0010]

According to the present invention, two driving rods arranged in parallel with each other, and driving means capable of driving the two driving rods independently of each other in the extending direction thereof. And a holding table rotatably held in a plane parallel to the extending direction with respect to each of the two driving rods.

As the driving means, four linear motors provided respectively at the ends of the two driving rods can be used.

The holding table is fixed to a pair of first holding members for rotatably fixing the holding table to the two driving rods, respectively, and to the two driving rods. The pair of second holding members on which the holding table is mounted are rotatably held by the two driving rods in a plane parallel to the extending direction.

Further, according to the present invention, the two driving rods are arranged so as to penetrate a vacuum vessel, and the holding table is arranged so as to be located inside the vacuum vessel. A characteristic linear motion mechanism is obtained.

The airtightness of the vacuum vessel can be realized by fixing a plate to an end of the driving rod and disposing a bellows between the vacuum vessel and the plate.

[0015]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIGS. 1A and 1B show an example in which a linear motion mechanism according to an embodiment of the present invention is applied to a laser processing apparatus. Here, FIG. 1A shows A in FIG. 1B.
FIG. 1B is a cross-sectional view taken along line 1-A1, and FIG. 1B is a cross-sectional view taken along line B1-B1 in FIG.

As shown in FIGS. 1A and 1B, the linear motion mechanism according to the present embodiment penetrates through a vacuum vessel 11 of a laser processing apparatus and positions both ends outside the vacuum vessel 11. Drive rods 12a and 12b arranged in parallel with each other, and four plates 13 fixed at or near the ends of the drive rods 12a and 12b, respectively.
Four linear motors 14 for linearly moving each plate 13 in the direction in which the driving rods 12a and 12b extend, and between the outer wall of the vacuum vessel 11 and each plate 13 to secure the vacuum vessel 11 are secured. And a bellows 15 provided.

Near one end of the drive rods 12a and 12b of the four linear motors 14 (right side in FIG. 1).
The two linear motors provided in the
A linear encoder 16 for detecting the positions of 2a and 12b is provided. The four linear motors 14 are divided into two sets for driving the driving rods 12a and 12b, respectively, and can be operated independently of each other.

A holding table 17 for holding an object to be processed is fixed to the two driving rods 12a and 12b in the vacuum chamber 11. A plurality of pins 18 protrude from the surface of the holding table 17, and a workpiece 19 such as a glass plate is placed on these pins. Note that a heater 20 is provided inside the holding table 17.

In the above configuration, the linear motion mechanism operates such that four linear motors 14 translate each plate 13 in a normal operation. That is, the four linear motors cooperate to move the driving rods 12a and 12b in the same direction and by the same amount. As a result, the holding table 17 is driven by the driving rods 12a and 12b.
The laser beam that moves linearly in the extending direction of the object and is incident from the quartz window 21 can irradiate the surface of the object to be processed over a wide range. Here, since there is no mechanical element in the vacuum chamber 11 that lowers the degree of cleanliness, such as a sliding portion, high speed, high accuracy, and a long life can be realized.

As described above, the drive mechanism according to the present embodiment is configured so that the drive rods 12a and 12b can be operated independently of each other. Therefore, by devising a method of fixing the holding table 17 to these driving rods 12a and 12b, the holding table 17 can be minutely rotated around an axis parallel to the θ axis as the center of rotation. With reference to FIG. 2, a method of fixing the holding table 17 to the driving rods 12a and 12b will be described.

As shown in FIGS. 2A and 2B, holding members 25a and 25b for fixing the holding table 17 are fixed to the driving rods 12a and 12b, respectively.

As shown in FIG. 2 (c), the holding member 25a has an upper member 26 and a lower member 27, which sandwich the driving rods 12a, 12b and fasten them to each other with screws. The drive rod 12
a, 12b. A ceramic ball 28 solid-lubricated is mounted on the upper surface of the upper member 26, and the holding table 17 is placed on the ceramic ball 28. In other words, the holding member 25a is
Although it is fixed to 2a, 12b, the holding table 17 is not fixed to the driving rods 12a, 12b.

On the other hand, the holding member 25b has an upper member 29, a lower member 30, and a rotation support member 31, as shown in FIG. The upper member 29 and the lower member 30 are similar to the case of the holding member 25a.
b and are fastened to each other by screws. And
The lower member 30 is rotatably held by a rotation support member 31 about an axis parallel to the θ axis as a rotation axis.

FIG. 3 is an enlarged view (partially sectional view) of the holding member 25b. As shown in FIG. 3, the rotation support member 31
It has a vacuum bearing 32 and holds a rotating shaft 33 fixed to the lower member 30. Thereby, the upper member 29 and the lower member 30 of the holding member 25b are rotatable around the θ axis as the rotation axis.

As described above, the holding members 25a and 25b
Is used to drive the two sets of linear motors in opposite directions (or only one set), the holding base 17 slightly rotates about an axis parallel to the θ axis as a rotation axis. . In this case, the rotation angle of the holding table 17 is obtained by detecting the position of each drive rod using a linear encoder attached to a linear motor.

[0027]

According to the present invention, the drive means is provided on the two drive rods, and the support is attached to these drive rods, so that the support is not affected by heating. Also, processing such as laser annealing can be performed in a high-speed, high-accuracy, and clean state without generating wear debris due to the movement of the support table.

Further, according to the present invention, the two driving rods can be driven independently of each other, and the support table is rotatably held with respect to the two driving rods. Thus, the support base can be minutely rotated without providing a special rotation mechanism.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

2A is a plan view, FIG. 2B is a front view, and FIG. 2C is a view for explaining a holding table 17 and holding members 25a and 25b in the linear motion mechanism of FIG. C1-C1
(D) is a sectional view taken along line D1-D1 of (a).

FIG. 3 is an enlarged view of a holding member 25b of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Vacuum container 12 Drive rod 13 Plate 14 Linear motor 15 Bellows 16 Linear encoder 17 Holder 18 Pin 19 Workpiece 20 Heater 21 Quartz window 25a, 25b Holding member 26 Upper member 27 Lower member 28 Ceramic ball 29 Upper member 30 Lower Member 31 Rotation support member 32 Vacuum bearing 33 Rotation shaft

Claims (5)

[Claims] 1. Two driving rods arranged in parallel with each other, driving means capable of driving the two driving rods independently of each other in the extending direction thereof, and A linear motion mechanism comprising: a holding table rotatably held in a plane parallel to the extending direction. 2. The linear motion mechanism according to claim 1, wherein said driving means is four linear motors provided at ends of said two driving rods, respectively. 3. A pair of first holding means, wherein said holding table rotatably fixes said holding table to said two driving rods.
And a pair of second holding members fixed to the two driving rods and mounting the holding table, respectively, with respect to each of the two driving rods in the extending direction. 3. The linear motion mechanism according to claim 1, wherein the linear motion mechanism is rotatably held in a plane parallel to the axis. 4. The apparatus according to claim 1, wherein the two driving rods are arranged so as to penetrate the vacuum vessel, and the holding table is arranged so as to be located inside the vacuum vessel. , 2 or 3 linear motion mechanism. 5. A plate is fixed to an end of the driving rod, and a bellows is disposed between the vacuum container and the plate to maintain the airtightness of the vacuum container. The linear motion mechanism according to claim 4, wherein