JP2004200576A - End effector for substrate carrying robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an end effector capable of loading and carrying a substrate warped by heat or the like in a stable state and capable of preventing generation of particles due to the movement of the substrate on the end effector and the collision of the substrate with respective parts of the end effector as to an end effector installed in a substrate carrying robot which is used for a semiconductor manufacturing device or the like to be used for manufacturing various kinds of semiconductor devices. <P>SOLUTION: A large-diameter groove having a diameter corresponding to the outer diameter of a plate-like substrate and prepared for preventing the substrate from sliding is formed, at least one small-diameter groove is formed on the inside of the large-diameter groove and a recess for a projected part formed on the lower surface side of the substrate deformed like a concave shape is formed. The outer diameter of the small-diameter groove is set to 50-80% the outer diameter of the large-diameter groove for preventing the slide of the substrate. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an end effector provided in a substrate transfer robot used in a semiconductor manufacturing apparatus or the like used when manufacturing various semiconductor devices, and particularly, to place and transfer a substrate in a state in which the substrate is aligned due to heat or the like. The present invention relates to an end effector capable of stably mounting a substrate when performing the operation.
[0002]
[Prior art]
Various semiconductor devices such as LSIs are manufactured through many surface treatments for substrates.
[0003]
An apparatus for performing such a process is collectively referred to as a semiconductor manufacturing apparatus, and includes an apparatus for forming a thin film such as a sputtering apparatus and a chemical vapor deposition (CVD), and an apparatus for performing a surface treatment such as etching and impurity implantation. It is.
[0004]
In such a semiconductor manufacturing apparatus, it is necessary to carry a substrate into a processing chamber or to carry out a processed substrate from a processing chamber, and in many cases, a substrate for carrying a substrate between chambers. It has a transfer robot.
[0005]
The substrate transfer robot will be described below with reference to a multi-chamber type sputtering apparatus as an example.
[0006]
FIG. 4 is a schematic plan view illustrating a conventional configuration of a multi-chamber type sputtering apparatus.
[0007]
In the sputtering apparatus shown in FIG. 4, a chamber arrangement including a separation chamber 1 arranged at the center, a plurality of processing chambers 2 provided around the separation chamber 1 and two load lock chambers 3 is provided.
[0008]
The separation chamber 1, the processing chamber 2, and the load lock chamber 3 are vacuum vessels that are evacuated by a dedicated or shared exhaust system, and each of the connection points of the separation chamber 1, the processing chamber 2, and the load lock chamber 3 A gate valve 4 is provided.
[0009]
Among these, the separation chamber 1 serves as a space for transporting substrates to the processing chamber 2 and the load lock chamber 3 while preventing the processing chambers 2 from being mutually air-tightly separated to prevent mutual contamination of the internal atmosphere. . For this reason, a substrate transfer robot 8 is provided in the separation chamber 1.
[0010]
At the time of substrate processing, the substrate transfer robot 8 first takes out the substrates 5 one by one from one of the load lock chambers 3 and sends them to each of the processing chambers 2. After the completion of the processing in each of the processing chambers 2, Return to one load lock chamber 3.
[0011]
One of the two processing chambers 2 is configured as a sputtering chamber 2A for performing predetermined sputtering. In the sputtering chamber 2A, there are provided a target made of a material to be formed into a film, a power application mechanism for sputtering the target, gas introduction means, a magnet mechanism for magnetron sputtering, a substrate holder for holding a substrate at a predetermined position, and the like. ing. With such a sputtering chamber 2A, a film of 1,000 to 10,000 angstroms of Ti, TiN, Al or the like is formed on the substrate.
[0012]
The other processing chamber 2 is configured as a preheat chamber 2B for preheating the substrate before sputtering, and the substrate 5 transferred into the preheat chamber 2B is heated at about 300 to 500 ° C. in the preheat chamber 2B. Is done.
[0013]
The transfer of the substrate 5 into the sputter chamber 2A or the preheat chamber 2B is performed by the above-described substrate transfer robot 8. The substrate transfer robot 8 includes a drive unit (not shown) and an arm 6 movable by the drive unit. Further, the arm 6 includes an end effector 7 for holding the substrate 5.
[0014]
Here, the end effector 7 is of a type that directly mounts and holds the substrate 5 on the surface (upper surface) of the end effector 7, or a pin is attached to the surface (upper surface) of the end effector 7, There is also a type that holds the substrate 5 on pins.
[0015]
FIG. 4 is a perspective view showing a conventional end effector 7 of a type in which the substrate 5 is directly placed and held on the surface (upper surface) of the end effector 7.
[0016]
FIG. 6 is a cross-sectional view showing a state in which the substrate 5 before processing in the processing chamber 2 is held by the end effector 7 shown in FIG. The end effector 7 is provided with a groove 9 having a shape conforming to the shape of the substrate 5 in order to prevent the substrate 5 from shifting during the transfer of the substrate. In FIG. 5, the dimension a indicates the outer diameter of the groove 9, and the dimension b indicates the depth of the groove 9.
[0017]
[Patent Document 1]
JP-A-7-297262
[Problems to be solved by the invention]
When a processing apparatus having a multi-chamber structure as described above is used, a substrate processed in the preheat chamber is distorted due to expansion due to heat. On the other hand, the substrate processed in the sputter chamber is also distorted by the compressive stress generated on the substrate surface during the formation of the thin film. When these distortions occur, the processed substrate may be deformed into a concave or convex shape.
[0019]
FIG. 7 is a cross-sectional view showing a state in which a processed substrate 5 is held by an end effector 7 of a type in which a conventional substrate is placed and held on the surface (upper surface) of the end effector.
[0020]
Although the processed substrate 5 may be warped as described above, for example, if the substrate 5 is warped in a concave shape as shown in FIG. 7, the substrate 5 placed on the end effector 7 Point contact with the bottom 9a of the groove 9 provided on the surface (upper side surface) of the effector 7 makes it difficult to transport the substrate 5 stably, and the substrate 5 shifts or falls off from the end effector 7. there were.
[0021]
If the substrate is unstable on the surface (upper surface) of the end effector 7, the substrate 5 moves in the groove 9 in the horizontal direction, so that the periphery of the substrate 5 and the peripheral corner 9 b of the groove 9 are separated. There was a problem that the particles collided and contacted each other, causing particles to be generated.
[0022]
[Means for Solving the Problems]
The present invention has been made in order to improve the above-mentioned problems, by providing means capable of holding a substrate in a state in which the shape and dimensions have changed due to stress generated on the substrate due to the influence of heat and the like, stable conveyance of the substrate, and The generation of particles caused by the collision of the substrate with the peripheral edge of the groove provided in the end effector during the transfer of the substrate could be suppressed.
[0023]
That is, the present invention is an end effector provided in a substrate transfer robot such as a semiconductor manufacturing apparatus and directly holding a substrate, wherein the end effector has a substrate displacement having a diameter corresponding to an outer diameter of a flat substrate. An end effector for a substrate transfer robot, comprising: a large-diameter groove for prevention; and at least one small-diameter groove provided inside the large-diameter groove.
[0024]
Here, the large-diameter groove is provided for mounting a substrate in a state in which a concave or convex shape is not deformed, fitting the substrate, and holding the substrate on an end effector.
[0025]
The small-diameter groove is provided to hold the lower surface side of the substrate deformed into a concave or convex shape by the stress generated on the substrate due to the influence of heat or the like in a stable state on the end effect. In other words, the small-diameter groove forms a receiving portion for escaping a convex portion formed on the lower surface side of the concavely deformed substrate, and abuts and holds the lower surface side of the concavely deformed substrate on the periphery thereof. Things.
[0026]
The present invention is a proposal aimed at preventing a substrate deformed in a concave shape from shifting on an end effector.
[0027]
When the substrate is deformed in a convex shape, unlike the case in which the substrate is deformed in a concave shape, the peripheral edge of the substrate comes into contact with the end effector, and the line segment in contact with the end effector is compared with the case in which the substrate is deformed in a concave shape. The distance is long. That is, the frictional force is larger than when the substrate is deformed into a concave shape, and the risk that the substrate moves on the end effector is small, so that it is not necessary to take special measures to prevent the substrate from being displaced after the deformation. It can be said that.
[0028]
However, for example, if grooves having different diameters are provided in a plurality of steps so that the diameter becomes smaller toward the inner side, even if the substrate is deformed in a convex shape, the diameter of the substrate is slightly smaller than the diameter of the deformed substrate. And the displacement on the end effector is more effectively prevented.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 3 is an explanatory diagram of a state where the substrate 5 is placed on the end effector 10 according to the embodiment of the present invention, as viewed from a side.
[0030]
According to the present invention, a substrate having a diameter corresponding to the outer diameter of a flat substrate 5 is provided on an end effector in order to stably hold a substrate deformed in a concave or convex shape due to stress generated in the substrate due to the influence of heat or the like. A large-diameter groove 11 for preventing displacement is provided, and a small-diameter groove 12 is provided inside the large-diameter groove 11. Here, it is preferable that the outer diameter of the small diameter groove 12 be 50% to 80% of the outer diameter of the large diameter groove 11.
[0031]
The amount of deformation of the substrate 5 placed and transported on the end effector 10 differs depending on the size, shape, and material of the substrate 5. Therefore, the dimensional ratio between the outer diameter of the small diameter groove 12 and the outer diameter of the large diameter height 11 is a matter to be determined according to the size, shape, and material of the substrate 5.
[0032]
On the other hand, in order to place the substrate 5 deformed into a concave shape on the end effector 10 in a stable state, the frictional force between the end effector 10 and the substrate 5 should be as large as possible. In order to increase the contact area between the end effector 10 and the substrate 5 in order to increase the frictional force between the end effector 10 and the substrate 5, as shown in FIG. The end effector 10 and the substrate 5 must be in contact with each other at the following three positions. In addition, the longer the arc length of the portion A and the portion C, the larger the contact area can be. Therefore, the outer diameter of the small diameter groove 12 is preferably as large as possible.
[0033]
However, when the ratio of the outer diameter of the small-diameter groove 12 to the outer diameter of the large-diameter groove 11 is large, the portion C (that is, the substrate 5) can slide in the direction of arrow 13 as shown in FIG. As a result, the two portions A and B cannot be brought into contact at the same time, so that the problem of substrate displacement cannot be solved. Such a state is remarkable when the amount of deformation of the substrate 5 is large.
[0034]
Conversely, if the ratio of the outer diameter of the small-diameter groove 12 to the outer diameter of the large-diameter groove 11 is small, it becomes difficult even to place the substrate 5 on the end effector 10. Also, if the ratio of the outer diameter of the small-diameter groove 12 to the outer diameter of the large-diameter groove 11 is too small, as shown in FIG. On the other hand, in the portion C, a gap may be formed between the end effector 10 and the substrate 5, and the substrate 5 may be more concavely curved. Therefore, such a state is not preferable.
[0035]
As described above, an appropriate ratio of the outer diameter of the small-diameter groove 12 to the outer diameter of the large-diameter groove 11 must be determined in consideration of the deformation amount of the substrate 5.
[0036]
When the factors to be considered are comprehensively determined, it is preferable that the outer diameter of the small-diameter groove 12 be 50% to 80% of the outer diameter of the large-diameter groove 11.
[0037]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0038]
FIG. 1 is a perspective view of an end effector 10 showing an embodiment of the present invention.
[0039]
The end effector 10 includes a large-diameter groove 11 having a diameter corresponding to the outer diameter of the flat substrate 5, and a single-step small-diameter groove 12 inside the large-diameter groove 11.
[0040]
FIG. 2 is a cross-sectional view showing a state where the substrate 5 after processing in the processing chamber 2 (FIG. 4) is placed and held on the end effector 10.
[0041]
The dimensions of the large-diameter groove 11 and the small-diameter groove 12 provided in the end effector 10 are such that an end effector provided with grooves having various dimensions is actually manufactured, and the substrate is actually transported. Were in contact with each other in an arc-shaped line, and a reference value was obtained as a dimension such that the substrate could be stably transferred.
[0042]
The end effector 10 shown in FIG. 2 is for transporting a 6-inch wafer (outer diameter φ150 mm) as the substrate 5, and the outer diameter a of the large-diameter groove 11 for preventing the displacement of the flat substrate is φ150.3 mm and the depth is The length b is 1 mm.
[0043]
With respect to the dimensions of the large-diameter groove 11, the dimensions of the small-diameter groove 12, which forms a receiving portion for the convex portion formed on the lower surface side of the substrate 5 deformed into a concave shape, have an outer diameter c of 115 mm and a depth of 115 mm. The length d is 0.2 mm. Therefore, the outer diameter of the small-diameter groove 12 is approximately 76% of the outer diameter of the large-diameter groove 11.
[0044]
When the end effector 10 having the above-described dimensions is used, the substrate 5 is not deformed, and is placed in a flat-plate shape in surface contact with the bottom surface 11 a of the large-diameter groove 11. 5 was held in the large-diameter groove 11 having an outer diameter equal to the outer diameter of No. 5, and was able to be transported in a stable state without rattling.
[0045]
In addition, even when the substrate 5 is deformed and has a concave shape, the substrate 5 is held in contact with the arc-shaped peripheral edge of the small-diameter groove 12, so that the substrate 5 can be transported in a stable state without rattling.
[0046]
As described above, the substrate 5 is stably held without rattling irrespective of the presence or absence of deformation, so that the vicinity of the peripheral edge of the substrate 5 collides with and contacts the peripheral edge corners of the large-diameter groove 11 and the small-diameter groove 12. And the generation of particles could be suppressed.
[0047]
The dimensions a, b, c, and d are determined as reference values that allow stable transfer of a substrate such as a semiconductor device wafer, and are not absolute dimensions, but rather the size of the substrate, Since there may be a slight difference in dimensions depending on conditions such as shape and material, design and adjustment are appropriately performed according to conditions such as the size, shape and material of the substrate.
[0048]
However, in the substrate used in the current semiconductor manufacturing, when the outer shape of the substrate to be conveyed is φLmm and the thickness of the substrate is tmm, as a rough guide, the outer diameter c is approximately φ0.8 Lmm and the depth d is approximately It changes as the value of the outer diameter a increases, and becomes a value of about 0.2 tmm or more.
[0049]
For example, assuming that the substrate 5 to be transported is an 8-inch wafer (outside diameter φ200 mm), the outside diameter a of the large-diameter groove 11 is φ200.3 mm, the depth b is 1 mm, and the outside diameter c of the small-diameter groove 12 is φ160 mm, The length d is 0.5 mm. In this case, the outer diameter of the small-diameter groove 12 is about 80% of the outer diameter of the large-diameter groove 11.
[0050]
As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. However, the present invention is not limited to such embodiments, and various modifications may be made within the technical scope understood from the claims. It can be changed to a different form.
[0051]
【The invention's effect】
As described above, the end effector of the present invention includes the large-diameter groove for preventing substrate displacement having a diameter corresponding to the outer diameter of the flat substrate, and the small-diameter groove is provided at least one step inside the large-diameter groove. Therefore, it is possible to form the relief of the convex portion formed on the lower surface side of the substrate deformed into a concave shape, and to reduce the outer diameter of the small-diameter groove to 50% of the outer diameter of the large-diameter groove for preventing substrate displacement. Since the size is set to 80%, the substrate can be stably transported. Further, by carrying the substrate in a stable state without rattling, it is possible to avoid collision and contact between the vicinity of the periphery of the substrate 5 and the corner of the periphery of the groove, and thus has an effect of suppressing generation of particles.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of an end effector of the present invention.
FIG. 2 is a cross-sectional view showing a state where a processed substrate is held by the end effector.
FIG. 3A is a diagram illustrating a state in which a concave substrate is stably mounted and held on an end effector.
(B) Explanatory drawing of the state where the ratio of the outer diameter of the small-diameter groove 12 to the outer diameter of the large-diameter groove 11 is large, and the concave substrate moves on the end effector.
(C) An explanatory view of a state in which the ratio of the outer diameter of the small-diameter groove 12 to the outer diameter of the large-diameter groove 11 is small, and the concave substrate is unstablely placed on the end effector.
FIG. 4 is a schematic plan view illustrating a configuration of a multi-chamber type sputtering apparatus including a substrate transfer robot to which an end effector is attached.
FIG. 5 is a perspective view showing an end effector of a conventional example.
FIG. 6 is a cross-sectional view showing a state in which a flat substrate is held by an end effector according to a conventional technique before processing.
FIG. 7 is a cross-sectional view showing a state in which a concave substrate is held by a conventional end effector after processing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Separation chamber 2 Processing chamber 2A Sputter chamber 2B Preheat chamber 3 Load lock chamber 4 Gate valve 5 Substrate 6 Arm 7, 10 End effector 11 Large diameter groove 12 Small diameter groove

Claims (2)

An end effector that is provided in a substrate transport robot such as a semiconductor manufacturing apparatus and directly holds a substrate,
The end effector includes a large-diameter groove for preventing substrate displacement having a diameter corresponding to the outer diameter of the flat substrate, and at least one small-diameter groove is provided inside the large-diameter groove. End effector for robots. 2. The end effector for a substrate transfer robot according to claim 1, wherein the outer diameter of the small-diameter groove is 50% to 80% of the outer diameter of the large-diameter groove for preventing substrate displacement.

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