JP3799336B2 - Handling method of ring chuck in substrate processing apparatus - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a substrate processing apparatus for clamping and processing a substrate on a substrate table.
[0002]
[Prior art]
A semiconductor wafer, a liquid crystal substrate, and a substrate such as an information recording disk are manufactured through many processes on the substrate surface. In a processing apparatus for processing such a substrate, the substrate is usually placed on a substrate table and clamped, and then the processing is started. In the present application, the term “clamp” means that the substrate is held so as not to move during processing.
[0003]
FIG. 2 is a front view for explaining the outline of the conventional substrate processing apparatus as described above.
The substrate processing apparatus shown in FIG. 2 is an example of a processing apparatus using a vacuum such as a sputtering apparatus or a CVD apparatus, and includes a vacuum chamber 1, a substrate table 2 housed in the vacuum chamber 1, and a substrate table 2. A ring chuck 3 that clamps the peripheral portion of the substrate 20 placed thereon, a drive rod 4 that is fixed at the lower surface of the ring chuck 3 and extends downward, and drives the ring chuck 3 by moving the drive rod 4 up and down. The ring chuck drive mechanism 5 is mainly configured.
[0004]
The ring chuck 3 has an annular shape that matches the shape of the substrate 20. That is, for example, in the case of a substantially circular shape such as a semiconductor wafer, it has an annular shape adapted to it. Then, the substrate 20 is clamped to the substrate table 2 so that the peripheral portion of the substrate 20 is pressed against the substrate table 2.
Specifically, the ring chuck drive mechanism 5 is a drive mechanism including a drive source such as an air cylinder that moves the drive rod 4 up and down, and clamps the substrate 20 by positioning the ring chuck 3 at a predetermined lower position. The clamp is released by raising it to a predetermined upper position.
[0005]
The substrate 20 is clamped by position control of the ring chuck 3. That is, clamping of the substrate 20 is achieved by positioning the lower surface of the ring chuck 3 at a height position (hereinafter referred to as a clamping position) where the surface of the substrate 20 is loosely touched and clamped. Specifically, the ring chuck drive mechanism 5 has a specific stopper and the like, and when the lower surface of the ring chuck 3 reaches the clamp position, the lowering of the drive rod 4 is stopped by the stopper. In other words, in a state where the lowering of the drive rod 4 is stopped by abutting against a stopper or the like (not shown), the positional relationship is such that the lower surface of the ring chuck 3 gently touches the surface of the substrate 20.
If the design is such that the lowering of the drive rod 4 stops by contacting the surface of the substrate 20, that is, the substrate 20 itself also serves as a stopper, the surface of the substrate 20 may be damaged by the collision of the ring chuck 3. This is because there is a risk of chipping.
[0006]
[Problems to be solved by the invention]
As described above, in the conventional substrate processing apparatus, the ring chuck is clamped by being positioned at a predetermined clamp position. However, the clamping force of the ring chuck cannot always be kept constant for several reasons as described below.
The first is the maintenance problem of the ring chuck. That is, in the case of a thin film forming apparatus, an etching apparatus, or the like, since the thin film material or the material to be etched adheres to the ring chuck, it is necessary to periodically replace the ring chuck. The ring chuck once used is reused after removing the adhering material. However, since the surface is removed by scraping the surface, the dimension of the ring chuck may change in millimeters during the removal process. That is, the thickness of the ring chuck may be slightly reduced. Since the above-described clamping position is determined and fixed in advance so that the ring chuck has a thickness as designed, the clamping force changes when the thickness of the ring chuck changes.
[0007]
Such a dimensional change of the ring chuck is also caused by variations in the dimensional accuracy of the ring chuck. That is, even if a new ring chuck is attached, the dimensional variation of each product is inevitable, so the clamping force cannot be made constant.
The second factor that prevents the substrate from being clamped with a constant force is a thermal problem. That is, when the thickness of the ring chuck and the length of the drive rod change due to heating, the clamping force of the substrate changes. This change may occur when the clamping force increases or decreases. If it is increased, the ring chuck may press the substrate with a strong force, resulting in damage to the substrate. If the clamping force is reduced, the clamp cannot be clamped as described above, and the position of the substrate is not fixed. It will be a situation.
The present invention has been made in order to solve such a problem, and an object thereof is to allow a substrate to be clamped and processed with a constant and stable force.
[0008]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the invention of claim 1 of the present application is a ring chuck handling method for handling a ring chuck to be brought into contact with a peripheral portion of a substrate placed on a substrate stage in a substrate processing apparatus,
Clamping the periphery of the substrate by bringing the ring chuck into contact with the periphery of the substrate placed on the substrate table;
Causing the ring chuck to release the substrate clamp; and
A step of replacing the ring chuck with another ring chuck from which the adhering material has been removed during maintenance,
Clamping the periphery of the substrate comprises :
A step in which a spring mechanism provided at the rear end of the drive rod whose front end is fixed to the ring chuck is operated , and the ring chuck clamps the peripheral portion of the substrate by the elastic force of the spring mechanism;
Releasing the clamp of the substrate comprises :
The drive rod moving mechanism having a member fitted to the drive rod is such that the ring chuck releases the substrate against the elastic force of the spring mechanism by pressing the stopper provided on the drive rod with the fitted member. A step of releasing the clamp by moving the drive rod,
In the step of clamping the peripheral portion of the substrate,
The drive rod moving mechanism causes the drive rod to move freely, and the other stopper prevents the fitted member from falling off the drive rod .
Further, in the invention of claim 2 of the present application, in the configuration of the invention of claim 1, the drive rod is provided with another stopper, and the fitted member is between the stopper and the other stopper. It is fitted to the drive rod at the position, and the falling off of the fitted member that is floating is prevented by this other stopper.
Further, in the invention of claim 3 of the present application, in the configuration of the invention of claim 1 or 2, the spring mechanism compensates for a dimensional change generated in the ring chuck when the adhering material is removed to obtain a constant clamping force. It has the structure of.
[0009]
【Example】
Examples of the present invention will be described below.
FIG. 1 is a front view for explaining an outline of a substrate processing apparatus in an embodiment of the present invention.
The substrate processing apparatus shown in FIG. 1 is an example of a processing apparatus using a vacuum such as a sputtering apparatus or a CVD apparatus as in FIG. 2, and includes a vacuum chamber 1 and a substrate table 2 housed in the vacuum chamber 1. And a ring chuck 3 for clamping the peripheral portion of the substrate 20 placed on the substrate table 2, and a drive rod 4 having an upper end fixed to the lower surface of the ring chuck 3 and extending downward. In the substrate processing apparatus shown in FIG. 1, a spring mechanism 6, a drive rod moving mechanism 7, and two upper and lower stoppers 81 and 82 are attached to the drive rod 4 outside the vacuum chamber 1.
[0010]
First, the substrate base 2 has a through-hole penetrating in the vertical direction, and the drive rod 4 is inserted into the through-hole so as to be vertically movable. The drive rod 4 penetrates the bottom plate portion of the vacuum chamber 1 and extends below the vacuum chamber, and a mechanical seal 11 is disposed in the penetrating portion. Incidentally, about three to four drive rods 4 are provided symmetrically about the circumference of the ring chuck 3.
The upper and lower stoppers 81 and 82 are flat bowl-shaped members fixed to the drive rod 4 in the portion exposed below the vacuum chamber 1.
As described above, the ring chuck 3 is provided so that it can be replaced during maintenance. The ring chuck 3 is configured such that the adhering material is removed during maintenance. If the adhering material is left as it is, the substrate 9 may be soiled by peeling and adhering to the substrate 20. Therefore, removing the adhering material at the time of maintenance has an effect of preventing the substrate 9 from being soiled.
[0011]
The spring mechanism 6 exhibits an elastic force so that the tip of the spring is fixed to the lower end of the drive rod 4 and pulls the drive rod 4, and is attached to each drive rod 4. As the spring mechanism 6, a type having a constant tensile force regardless of the extension of the spring is commercially available as long as it is within a certain range. Further, the force of the spring mechanism 6 acting on the drive rod 4 is considerably weak so that the surface of the substrate 20 is not damaged even if the ring chuck 3 abuts against the substrate 20 when the substrate 20 is clamped as described later. It is set to strength.
[0012]
The drive rod moving mechanism 7 moves the drive rod 4 upward, moves the ring chuck 3 upward against the elastic force of the spring mechanism 6 to release the clamp of the substrate 20, and has two upper and lower stoppers. A sliding head 71 that is slidably fitted to the drive rod 4 in a portion between 81 and 82; an arm 72 that extends downward with the sliding head 71 fixed to the tip; and a rear end of the arm 72 And a drive source 73 attached thereto.
The drive rod 4 in this embodiment has a circular cross section, and the sliding head 71 has a through hole having an inner diameter that matches the outer diameter of the drive rod 4, and the drive rod 4 is fitted into the through hole. It is arranged to let you. A sliding member such as a bearing is disposed inside the sliding head 71 to facilitate sliding.
[0013]
As the drive source 73, various drive sources such as a fluid cylinder or a servo motor using air or oil can be used. As will be described later, the drive source 73 in this embodiment simply moves the ring chuck 3 and releases the clamp, so that highly accurate position control is not required and the range of usable drive sources is wide.
The vacuum chamber 1 is an airtight one provided with a gate valve (not shown) for loading and unloading the substrate 20, and the inside is exhausted by an exhaust system (not shown) connected to an exhaust port (not shown). . In the vacuum chamber 1, a specific gas introduction system, an electrode for discharge, and the like are appropriately arranged according to the content of processing. In addition, a transfer mechanism (not shown) that places the loaded substrate 20 on the substrate table 2 and removes the substrate 20 from the substrate table 2 and carries it out after the processing is disposed in the vacuum chamber 1.
[0014]
Next, the operation of the substrate processing apparatus according to the above configuration will be described, which also serves as an explanation of the method of the embodiment.
In the initial state, the ring chuck 3 is in the upper position. That is, the drive source 73 of the drive rod moving mechanism 7 is operated in advance, the sliding head 71 is raised, the upper stopper 81 is pressed to move the drive rod 4 upward, and the ring chuck 3 is pushed up to the upper position. The ring chuck 3 is stopped at the upper position. This state is a state against the elastic force of the spring mechanism 6, and the drive source 73 applies a force to the drive rod 4 so as to maintain this state.
[0015]
First, a gate valve (not shown) is opened, and the substrate 20 is transferred by a transfer mechanism (not shown) and placed on the substrate table 2.
Next, the drive source 73 operates to lower the sliding head 71 to a predetermined position. As the sliding head 71 descends, the drive rod 4 begins to descend by the force of the spring mechanism 6, and the lower surface of the ring chuck 3 comes into contact with the substrate 20 and stops. As a result, the substrate 20 is clamped with respect to the substrate table 2. Since the force of the spring mechanism 6 is considerably weak as described above, at this time, the ring chuck 3 abuts very softly on the surface of the substrate 20 and stops descending.
[0016]
On the other hand, the sliding head 71 descends to a predetermined lower position and stops. This position is an intermediate height position between the upper and lower stoppers 81 and 82 in a state where the ring chuck 3 clamps the substrate 20 as described above. However, it does not have to be exactly in the middle, and may be a position between the upper and lower two stoppers 81 and 82. Further, in a state where the force of the drive source 73 with respect to the drive rod 4 is released, the force acting on the drive rod 4 is only the force of the spring mechanism 6, and in that sense, the drive rod 4 is in a floating state.
Then, after the substrate 20 is clamped as described above, a predetermined process is performed. When the process is completed, the drive rod moving mechanism 7 operates again to move the drive rod 4 upward, and the ring chuck 3 is moved to the upper position. Raise to. As a result, the clamping of the substrate 20 is released, and the substrate 20 is carried out by a transport mechanism (not shown).
[0017]
In the above-described embodiments, as described in the column “Problems to be Solved by the Invention”, the dimensions of the ring chuck 3 change and the thickness becomes thin, or the drive rod 4 and the like expand due to thermal expansion. Even in this case, since the ring chuck 3 is in a floating state in which only the pulling force of the spring mechanism 6 works, the spring mechanism 6 operates so as to compensate for such dimensional change and thermal expansion. Accordingly, the clamping force of the substrate 20 is always constant regardless of such dimensional changes and thermal expansion, and the substrate 20 can be clamped stably.
In addition, in this embodiment, the spring mechanism 6 having a constant tensile force is employed regardless of the length of extension of the spring, so that the clamp can be performed more stably. Even if a normal spring mechanism is used, since the dimensional change and thermal expansion are on the order of millimeters, the spring pulling force can be regarded as constant and may be practically acceptable.
In the above embodiment, the lower stopper 82 prevents the sliding head 71 from falling off. Since the lower stopper 82 prevents the sliding head 71 from falling off, the reliability is higher.
[0018]
As described above, in the method of this embodiment, the clamp, that is, the pressing of the substrate 20 against the substrate table 2 by the ring chuck 3 is performed by the force of the spring mechanism 6, and the ring chuck is fixed to the clamp position as in the prior art. 3 is not performed by position control for positioning the lower surface of 3. Therefore, the clamping force is constant regardless of the dimensional change of the ring chuck 3 and the thermal expansion of the drive rod 4 and the like, and the substrate 20 can be clamped stably. For this reason, there is no problem that the clamping force is reduced and the substrate is moved during the processing, and conversely, the clamping force is too strong and the substrate is damaged.
In the above embodiment, the ring chuck 3 has been described as moving up and down to clamp or release the substrate 20, but it may move in the lateral direction. That is, for example, in an apparatus of a type that holds the substrate upright, the ring chuck 3 is also placed upright, so that the drive rod 4 moves in the lateral direction.
[0019]
【The invention's effect】
As described above, according to the present invention, since the spring mechanism operates so as to compensate for the dimensional change of the ring chuck and the thermal expansion of the drive rod, the clamping force of the substrate becomes constant, and the substrate is always stable. Can be clamped. In addition to this, the ring chuck is replaced at the time of maintenance and the adhered material is removed, so that the substrate is prevented from being soiled.
[Brief description of the drawings]
FIG. 1 is a front view illustrating an outline of a substrate processing apparatus in an embodiment of the present invention.
FIG. 2 is a front view for explaining the outline of a conventional substrate processing apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vacuum chamber 2 Substrate stand 20 Substrate 3 Ring chuck 4 Drive rod 6 Spring mechanism 7 Drive rod moving mechanism

Claims (3)

A ring chuck handling method for handling a ring chuck to be brought into contact with a peripheral portion of a substrate placed on a substrate stage in a substrate processing apparatus,
Clamping the periphery of the substrate by bringing the ring chuck into contact with the periphery of the substrate placed on the substrate table;
Causing the ring chuck to release the substrate clamp; and
A step of replacing the ring chuck with another ring chuck from which the adhering material has been removed during maintenance,
Clamping the periphery of the substrate comprises :
A step in which a spring mechanism provided at the rear end of the drive rod whose front end is fixed to the ring chuck is operated , and the ring chuck clamps the peripheral portion of the substrate by the elastic force of the spring mechanism;
Releasing the clamp of the substrate comprises :
The drive rod moving mechanism having a member fitted to the drive rod is such that the ring chuck releases the substrate against the elastic force of the spring mechanism by pressing the stopper provided on the drive rod with the fitted member. Moving the drive rod to release the clamp,
In the step of clamping the peripheral portion of the substrate,
A method of handling a ring chuck in a substrate processing apparatus, wherein a drive rod moving mechanism causes the drive rod to move freely . The drive rod is provided with another stopper, and the fitted member is fitted to the drive rod at a position between the stopper and the other stopper, and the fitted member is free to move. 2. A method of handling a ring chuck in a substrate processing apparatus according to claim 1, wherein the drop-off is prevented by the other stopper. 3. The method of handling a ring chuck in a substrate processing apparatus according to claim 1, wherein the spring mechanism compensates for a dimensional change that occurs in the ring chuck when the adhered material is removed, thereby obtaining a constant clamping force.

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