JPH10335432A - Processor with processing container having direct acting type mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processor which includes a processing container having a rotary driving mechanism for horizontally rotating an object to be processed within the processing container. SOLUTION: A processor includes a processing container 1, two driving support shafts 2a and 2b both ends of which are passed through walls of the container 1 and externally extruded, and linear motors 4a-1, 4a-2, 4b-1 and 4b-2 provided at the both ends of the shafts for moving the associated shafts parallelly. Within the container, a substrate carrier base 6 is supported by a driving support shaft through a support frame 13. Provided at locations where the shafts 2a and 2b are passed through the walls of the container 1 are vacuum bellows 5a and 5b so as to keep an air-tightness within the container 1. The substrate carrier base is provided within the container 1 as combined with the two driving support shafts 2a and 2b to be rotated by a rotary driving mechanism for rotating the carrier base 6 in its horizontal condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus provided with a processing container having a linear motion mechanism for moving a holding table for holding an object to be processed in the processing container. This type of processing apparatus is particularly suitable for an apparatus that performs processing with a laser beam on a processing target such as glass in a vacuum or an inert gas atmosphere in a processing container, such as a laser annealing apparatus.

[0002]

2. Description of the Related Art A laser annealing apparatus will be described as an example of this type of processing apparatus. When performing laser annealing by a laser annealing apparatus, an object to be processed is held in a holding table and placed in a vacuum vessel, and the surface of the object to be processed is irradiated with laser light through a quartz window. By moving the holding table in the vacuum vessel, a large area on the surface of the processing object can be sequentially irradiated with laser light.

The holding table is provided with two drive shafts extending to the outside of the vacuum vessel, and can be moved by a drive mechanism using a combination of a servo motor and a ball screw disposed in the vacuum vessel. I have. The holding table also
Guidance at the time of movement is performed by two guide mechanisms arranged in the vacuum vessel. In addition, a bellows is attached as an airtight mechanism between the drive shaft outside the vacuum vessel and the wall of the vacuum vessel, and the airtightness of the vacuum vessel is maintained.

[0004]

However, depending on the form of processing on the object, it may be necessary to rotate the object horizontally in the vacuum vessel. However, the conventional processing apparatus does not have such a rotation drive function, and there is a limitation in the form of processing.

In order to stably obtain the effect of laser annealing, an object to be processed may be heated. For this reason, a heater is embedded in the holding table. When the holding table is heated, extra force is applied to the sliding portions of the two guide mechanisms due to thermal strain. This extra force makes it difficult for the holding table to move, and in extreme cases, may make it impossible to move.

Further, since the conventional driving mechanism is based on a combination of a servomotor and a ball screw, there is a backlash, and it is difficult to obtain a highly accurate positioning and high-speed response of the holding table.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a processing apparatus provided with a processing container having a rotation drive mechanism for horizontally rotating an object to be processed in the processing container.

Another object of the present invention is to provide a processing apparatus provided with a processing container capable of obtaining high-precision positioning and high-speed response of an object to be processed.

[0009]

According to the present invention, a processing vessel maintained in an airtight state, and disposed inside the processing vessel, both ends of which are led out through the wall of the processing vessel to the outside. Two driving spindles, and at a location where the two driving spindles penetrate the wall of the processing container,
So that the drive shaft can be translated in the axial direction,
And an airtight mechanism for isolating the inside of the processing container from the outside so that airtightness in the processing container is maintained, and an airtight mechanism attached to at least one end of the two driving support shafts, A drive mechanism by a linear motor capable of moving the support shafts independently in the axial direction with respect to the processing container; and the two drive support shafts in the processing container, And a holding table for holding
A processing apparatus provided with a processing container having a linear motion mechanism, comprising: a rotation driving mechanism for rotating the holding table in a horizontal state in the processing container.

The holding table is rotatably supported by a support frame fixed to the two drive shafts, and the rotary drive mechanism is also mounted on the support frame.

[0011] The rotation drive mechanism includes a rotation mechanism connected to the stepping motor and the holding table, and a transmission mechanism for transmitting the rotation force of the stepping motor to the rotation mechanism.

Further, it is preferable that at least one of the inner wall of the processing vessel and the holding table is provided with a heating means for heating the object to be processed.

According to the present invention, a position detector is provided on one of the plurality of linear motors for detecting the position of the holding table, and the plurality of linear motors are positioned from the position detector. A feedback control system for controlling based on the detected value and the position command value, wherein the feedback control system is at a subsequent stage of a position controller that creates a control amount command value based on the position detected value and the position command value, A control amount command estimated value obtained by filtering the control amount command value with a secondary low-pass filter; and an inverse model of the control object simulating the linear motor and load and the position detection using a secondary low-pass filter. A disturbance observer for estimating a disturbance force based on a difference from an actual thrust value command estimated from the value, and a subtractor for compensating the disturbance by subtracting the disturbance force from the control amount command value. Processing apparatus is provided which is characterized in that a disturbance compensator.

[0014]

FIG. 1 is a schematic plan sectional view of a processing container according to a preferred embodiment of the present invention, and FIG. 2 is a schematic sectional view taken along line AA of FIG. FIG. 3 is a schematic sectional view taken along line BB in FIG.

Driving support shafts 2a and 2b for forming a linear motion mechanism are provided inside a processing vessel 1 capable of evacuating the inside.
Are arranged parallel to each other. Driving spindles 2a and 2
Both ends of b are led out to the outside through the side wall of the processing container 1. The processing vessel 1 is evacuated, and after that, an inert gas may be introduced in some cases. The processing container 1 is also fixed on a base (not shown).

Both ends of the driving support shafts 2a and 2b are respectively connected to linear motors 4a-1, 4a-2, 4b-1, and 4b- having a linear guide mechanism via a supporting structure 3.
2 are connected. These linear motors 4a-1,
By 4a-2, 4b-1, and 4b-2, the driving support shafts 2a and 2b can be driven independently of each other in the axial direction.

A portion of each of the driving support shafts 2a and 2b led out of the processing vessel 1 is covered with a vacuum bellows 5a, 5b as an airtight mechanism. Vacuum bellows 5a,
One end of 5 b is attached to the side wall of the processing container 1, and the other end is attached to the structure 3. The airtightness of the processing container 1 is maintained by such vacuum bellows 5a and 5b.

A holding table 6 is arranged in the processing vessel 1. The holding table 6 is rotatably supported by the driving support shafts 2a and 2b, and the supporting structure will be described later. A plurality of pins 7 protrude from the upper surface of the holding table 6, and a substrate 8 such as glass to be annealed is placed on the pins 7. A heater (not shown) is provided in the holding table 6, and the substrate 8 is heated by the heater. A heat shield 9 is provided on the lower surface of the holding table 6. The holding table 6 and the heat shield plate 9 are supported by a support plate 10. The heater may be provided on the inner wall of the processing container 1, for example, on the inner wall of the ceiling, or may be provided in a lower area where the holding table 6 moves. In any case, a water cooling plate 12 is provided below the heater so as not to hinder the movement of the mechanism supporting the holding table 6, and a space in the processing vessel 1 below the water cooling plate 12 is provided. Temperature rise is suppressed. A quartz window 1-1 is provided on the upper surface of the processing chamber 1, and laser light from an optical system is introduced into the processing chamber 1 through the quartz window 1-1.

Linear motors 4a-1, 4a-2, 4b-
By driving the support shafts 2a and 2b in the axial direction by driving the support shafts 1 and 4b-2, the substrate 8 can be moved together with the holding table 6 in the processing container 1. Linear motors 4a-1, 4a- for moving the holding table 6
Although drive control of 2, 4b-1, 4b-2 will be described later, linear encoders 11a-1, 11a-2, 11b-1, 11b are provided on side surfaces of the linear motors 4a, 4b, respectively.
b-2 is provided. These linear encoders 11a
-1, 11a-2, 11b-1, and 11b-2 from the linear motors 4a-1, 4a-
Feedback is provided to the drive control systems 2, 4 b-1 and 4 b-2, and control is performed such that the holding table 6 follows the position target value.

In this embodiment, the driving support shafts 2a and 2a
b on both sides of the linear motor 4a-
1, 4a-2, 4b-1, and 4b-2, the linear motors are driven by the driving support shafts 2a and 2b.
It may be provided only at one end of b. In this case, a linear guide mechanism is provided on the other end side of the driving support shafts 2a and 2b, and it is not necessary to install a linear encoder on the other end side. In addition, the structure 3 on the side of the linear motor 4a-1 and the structure 3 on the side of the linear motor 4b-1 are separately provided so that the driving support shafts 2a and 2b can be driven independently. The structure 3 on the -1 side and the structure 3 on the linear motor 4b-1 side may be integrated.

Next, the support structure of the holding table 6 will be described. In FIG. 1, the holding table 6 is indicated by a dashed line for convenience. The holding table 6 is rotatably supported by a support plate 10 via a support frame 13 fixed to two driving support shafts 2a and 2b at one end side and the other end side in the moving direction. A rotation mechanism 14 is disposed on the support frame 13 immediately below the center of the support plate 10.
Motor 15 for transmitting rotational driving force to the motor
Is arranged. The rotation mechanism 14 has an upper end on the support plate 10.
And a lower end thereof is connected to a rotation shaft of the stepping motor 15 via a steel belt 16. Note that the stepping motor 15 can be used in a vacuum.
In any case, the rotation mechanism 14 is used for positioning the substrate 8 by rotating the holding table 6 in a horizontal state during processing.

Referring also to FIG. 4, the rotating mechanism 14 includes a harmonic drive 14-2, a cross roller ring 14-
Harmonic drive 1 having a high reduction ratio by rotating a stepping motor 15 with a steel belt 16
4-2. In order to enable the positioning of the holding table 6 with high accuracy, a cross roller ring 14-3 is provided as a final stage guide. Further, a water-cooling cylinder 18 is provided outside the rotation mechanism 14 and a water-cooling cylinder (not shown) is provided outside the stepping motor 15 so that the above-described elements are used in their heat-resistant environment. . Power is supplied to the stepping motor 15 through a flexible heat-resistant cable (not shown) so as not to hinder the traveling of the holding table 6.

In this embodiment, a stepping motor 15 having a high resolution which can be used in a vacuum is used as a driving source, and a rotational driving force is transmitted to a driving shaft of a harmonic drive 14-2 by a stainless steel belt 16 without backlash. . For harmonic drive 14-2, 1/16
The speed is reduced at a high reduction ratio of 0 and transmitted to the driven shaft, and the cross roller ring 14-3 made of stainless steel is used as a guide for the output shaft at the final stage. To ensure high rotational accuracy,
The rotary encoder 14-4 is the harmonic drive 1
The positioning control is performed by a feedback control system described later, which is provided on the driven shaft side of 4-2. The water-cooling cylinder 18 and the water-cooling cylinder outside the stepping motor 15 each have internal components that do not exceed 80 ° C.

As described above, the movement of the driving support shafts 2a and 2b is not affected by the heat of the heater outside the processing vessel 1, and the linear motors 4a-1, 4a-2, 4b-1, and 4b are moved.
It is guided by a linear guide mechanism that guides the traveling of b-2. By using such a linear motor drive mechanism, the resonance frequency of the entire traveling system including the holding table 6 and the support frame 13 can be increased, and the holding table 6 can be positioned at high speed and with high accuracy, and can follow the trajectory. Performance can be improved.

Referring to FIGS. 5 to 7, a feedback control system of a linear motor and a stepping motor applied to the embodiment of the present invention will be described. In the following description, the moving direction of the holding table 6 is defined as the X axis, and the center in the rotation direction is defined as the θ axis.

In FIG. 5, the linear motors 4a-1 and 4a-4
Here, the control for a-2, 4b-1, and 4b-2 is such that the position detection value of the linear encoder 11a-1 is fed back to detect a deviation from the X-axis position command value, and this deviation is sent to the position controller 51. give. The position controller 51 creates a control amount command value for the X axis based on the deviation. Further, a disturbance compensator 53 using a disturbance observer 52 is added to the control loop of the feedback control system to cancel a disturbance factor such as a change in friction characteristics of the linear bearing guide. The current command values output from the disturbance compensator 53 are the linear motors 4a-1, 4a-2, 4b
-1 and 4a-2 motor amplifiers 54a-1 and 54a-
2, 54b-1, 54b-2, and each motor amplifier controls the corresponding linear motor based on the given current command value.

The operation of the feedback control system according to the present invention having the above configuration will be described. According to this feedback control system, by the configuration of each element described so far,
High positioning accuracy can be secured over the entire stroke range.

FIG. 6 shows details of the disturbance compensator 53 added to the feedback control system. First, in the disturbance observer 52, a second-order low-pass filter (Gs)
The control amount command value output from the position controller 51 is filtered using the filter 52-1 consisting of. Further, an inverse model (Ms ² / Kf, where Ms is the mass of the linear motor and the load, Kf is the motor thrust constant) of the control object simulating a plurality of linear motors and loads, and a secondary low-pass filter (Gs ), The actual thrust value command value applied to the control target is estimated from the position detection value detected by the linear encoder 11a-1.

Then, the filter 5 is output by the subtractor 52-3.
By calculating the difference between the outputs of 2-1 and 52-2, the disturbance force applied to the control target is estimated, and the estimated disturbance force is subtracted from the control amount command value by the subtractor 54 to obtain the disturbance force. To compensate. As described above, by using a model composed of the linear motor and the mass of the load as the control target model when estimating the actual thrust, it is possible to estimate and compensate for fluctuations in the guide friction of the linear bearing as a disturbance force.

As described above, according to the present invention, the disturbance compensator 53 using the disturbance observer 52 estimates the fluctuation of the guide friction of the linear guide mechanism which fluctuates at the position of the holding table 6 as a disturbance, and estimates these disturbance factors. Can be compensated for.

Next, a feedback control system in the rotary drive mechanism will be described with reference to FIG. Control of the stepping motor 15 is performed by the rotary encoder 14.
The position detection value of −4 is fed back to detect a deviation from the θ-axis position command value, and this deviation is given to the position controller 61. The position controller 61 creates a control amount command value for the θ axis based on the deviation and outputs a pulse command. The pulse command output from the position controller 61 is given to a motor driver 62 for the stepping motor 15, and the motor driver 62 controls the stepping motor 15 based on the given pulse command.

FIG. 8 is a schematic plan view of the entire laser annealing apparatus provided with the above-mentioned processing container. The laser annealing apparatus has, in addition to the processing container 1, a transfer chamber 22 for the substrate 8, a carry-in chamber 23, and a carry-out chamber 24. The optical system for laser light irradiation is a homogenizer 4
1. It comprises a CCD camera 42 and a video monitor 43.

The processing chamber 1 and the transfer chamber 22 are connected via a gate valve 25. Similarly, the transfer chamber 22 and the carry-in chamber 23, and the transfer chamber 22 and the carry-out chamber 24 are connected via gate valves 26 and 27, respectively. Vacuum pumps 31, 32 are provided in the processing container 1, the carry-in chamber 23 and the carry-out chamber 24, respectively.
And 33 are provided, and the inside of each chamber is evacuated when the substrate 8 is transferred. A transfer robot 28 is accommodated in the transfer chamber 22. The transfer robot 28 transfers the processed substrate or the unprocessed substrate between the processing container 1, the loading chamber 23, and the unloading chamber 24.

In the optical system, the laser beam output from the excimer laser device 44 that has emitted a pulse is incident on the homogenizer 41 through the attenuator 45. The homogenizer 41 changes the cross-sectional shape of the laser beam into an elongated shape. The laser beam that has passed through the homogenizer 41 is
The substrate in the processing chamber 1 is irradiated through the elongated quartz window 1-1 corresponding to the sectional shape of the laser beam. The relative position between the homogenizer 41 and the substrate is adjusted so that the surface of the substrate coincides with the homogenized surface.

The substrate is moved in a direction orthogonal to the long axis direction of the quartz window 1-1 by the linear motion mechanism described with reference to FIG. By moving the substrate at such a speed that part of the irradiation area for one shot overlaps part of the irradiation area in the previous shot, a large area on the substrate surface can be irradiated. The substrate surface is photographed by the CCD camera 42, and the substrate surface being processed can be observed on the video monitor 43. Linear motors 4a-1, 4a-2, 4b-1, 4b
-2, gate valves 25 to 27, transfer robot 28,
The operations of the homogenizer 41 and the excimer laser device 44 are controlled by the control device 40.

Returning to FIGS. 1 and 2, the substrate 8 is moved while irradiating a laser beam having a long sectional shape in a direction perpendicular to the direction of movement of the substrate 8 so that the substrate 8 is moved.
Can be annealed over a wide area of the surface. Especially,
By heating the substrate 8, the effect of laser annealing can be stabilized.

In the linear motion mechanism according to the present embodiment, even if the holding table 6 is heated to cause thermal distortion, the driving support shafts 2a, 2b
Are linear motors 4a-1, 4a-2, 4b
-1 and 4b-2, which are outside the processing container 1 and are not affected by thermal distortion caused by a heater in the processing container 1. Therefore, the holding table 6 can be stably moved even when the holding table 6 is heated. In particular, the linear motor can drive the holding table 6 at high speed, and can also perform positioning with high accuracy.

In the above embodiment, the laser annealing apparatus has been described as an example. However, the processing vessel shown in FIGS. 1 and 2 can be applied to other apparatuses. For example,
It is also effective in the case of a processing container that requires a linear motion mechanism and a rotation drive mechanism in an environment that needs to be isolated from the outside, such as when a special chemical is used.

[0039]

As described above, according to the present invention,
In addition to adopting a structure in which the guide mechanism and drive mechanism of the linear motion mechanism can be installed outside the processing vessel, a linear motor is used as the drive system, and a disturbance compensator using a disturbance observer is used in the feedback control system. This makes it possible to configure a linear motion mechanism having a long life and a high tracing capability of the holding table, that is, the substrate to be processed, with high speed and high accuracy.

In addition, by providing a unitized rotation mechanism capable of rotating with high precision in the processing container,
The holding table can be rotationally positioned with high accuracy without a driving source from the outside.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a processing container according to a preferred embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a view for explaining a support structure of the holding table shown in FIG. 1, and is a cross-sectional view taken along line BB in FIG. 2;

FIG. 4 is a half sectional view showing an enlarged view of the rotation drive mechanism shown in FIG. 2;

FIG. 5 is a block diagram showing a feedback control system of the linear motor shown in FIG.

6 is a block diagram showing a configuration of a disturbance compensator in the feedback control system shown in FIG.

FIG. 7 is a block diagram showing a feedback control system of the stepping motor shown in FIG.

FIG. 8 is a plan view showing a schematic configuration when the processing container of FIG. 1 is applied to a laser annealing apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Processing container 1-1 Quartz window 2a, 2b Driving support shaft 3 Structure 4a-1, 4a-2, 4b-1, 4b-2 Linear motor 5a, 5b Vacuum bellows 6 Holder 7 Pin 8 Substrate 9 Heat shield Plate 10 Support plate 11a-1, 11a-2, 11b-1, 11b-2 Linear encoder 12 Water cooling plate 13 Support frame 14 Rotation mechanism 14-2 Harmonic drive 14-3 Cross roller ring 15 Stepping motor 16 Steel belt

Claims (5)

[Claims] 1. A processing container maintained in an airtight state, two driving spindles disposed in the processing container, both ends of which are led out to the outside through respective walls of the processing container, At a position where the two driving support shafts penetrate the wall of the processing container, the two driving support shafts can be translated in the axial direction, and the airtightness in the processing container is maintained. An airtight mechanism for isolating the inside and the outside of the processing container, and attached to at least one end of the two driving shafts, and the two driving shafts are respectively disposed with respect to the processing container. A driving mechanism by a linear motor that can be independently moved in the axial direction; a holding table combined with the two driving spindles in the processing container to hold a processing target; In the above, the holding table is in a horizontal state. Processing apparatus including a processing container having a linear motion mechanism which comprises a rotational drive mechanism for rotating. 2. The processing apparatus according to claim 1, wherein the holding table is rotatably supported by a support frame fixed to the two drive shafts, and the rotation drive mechanism is connected to the support frame. A processing device characterized by being mounted on a computer. 3. The processing apparatus according to claim 2, wherein the rotation drive mechanism includes a rotation mechanism connected to a stepping motor and the holding table, and a transmission mechanism that transmits a rotation force of the stepping motor to the rotation mechanism. A processing device comprising: 4. The processing apparatus according to claim 1, wherein, of the inner wall of the processing container and the holding table, at least the holding table is provided with heating means for heating the object to be processed. A processing device, comprising: 5. The processing apparatus according to claim 1, wherein a position detector provided in one of the plurality of linear motors for detecting a position of the holding table, and the position detection of the plurality of linear motors is performed. A feedback control system for controlling based on a position detection value and a position command value from a device, wherein the feedback control system generates a control amount command value based on the position detection value and the position command value. In the subsequent stage, a control amount command estimated value obtained by filtering the control amount command value by a secondary low-pass filter, and an inverse model and a secondary low-pass filter of the control object simulating the linear motor and the load. A disturbance observer for estimating a disturbance force based on a difference from an actual thrust value command estimated from the position detection value, and compensating for the disturbance by subtracting the disturbance force from the control amount command value. That subtractor and processing apparatus characterized in that a disturbance compensator including.