JP2003170382A - Robot for carrying substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten the carrying time of a semiconductor substrate between carrying positions. <P>SOLUTION: This robot for carrying substrate comprises a chuck rotation driving head rotatably supported on the tip rotating shaft of a robot arm 5, a plurality of drive motors stored in the chuck rotation driving head, and a plurality of substrate holding chucks 30 having end effectors 32 swung around rotating axes R<SB>1</SB>and R<SB>2</SB>orthogonal to a sloped surface formed in one face of the skin of the chuck rotatingly driving head by a rotating force transmitted thereto from the output shafts of the plurality of drive motors. The substrate holding chuck 30 sucking a substrate W to the tip of the end effectors 32 and/or the end effector 32 of the substrate holding chuck 30 not sucking the substrate W is position-controlled by the independent or synchronous rotation operation of the drive motor corresponding to the substrate holding chuck 30. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate transfer robot, in which a plurality of end effectors attached to a robot arm are operated in parallel in a predetermined sequence to transfer a substrate such as a wafer between substrate transfer positions. The present invention relates to a substrate transfer robot that can be efficiently transferred.

[0002]

2. Description of the Related Art In recent years, in a semiconductor manufacturing wafer process, a manufacturing facility for carrying out batch processing to single-wafer processing has become mainstream for the purpose of improving accuracy and throughput of manufactured wafers. At this time, various arm drive type substrate transfer robots are used for efficient transfer of wafers between the chambers. In addition, various twin-arm robots have been developed in which two robot arms are operated in a predetermined sequence in order to improve the efficiency of the substrate transfer. Since the normal twin-arm type substrate transfer robot is designed as a scalar type robot, by moving the arms arranged with a slight height difference in each plane, multiple wafers can be moved at a predetermined timing. The substrate is transferred to the target substrate transfer position. For this reason, when a large-diameter wafer or glass substrate is placed on the end effector at the end of the robot arm for conveyance, the platform of the platform must be installed to secure the turning radius of the end effector with the substrate placed. There is a problem that the flat area increases.

For the purpose of reducing the installation area of the substrate transfer apparatus, when two end effectors at the tip of the robot arm are horizontally installed,
There has been proposed a substrate transfer device which is attached to the rotary head at an angle symmetrical to the rotary axis of the rotary head. In this substrate transfer device, the end effector attached in this way rotates in the plane in contact with the conical side surface by the rotation of the rotary head (Japanese Patent Laid-Open No. 2001-2173).
(See Japanese Patent Publication No. 00).

FIG. 11 is a perspective view showing a schematic configuration of the substrate transfer device of FIG. 10. As shown in the figure, the substrate transfer device 50 includes a robot arm 52 rotatably provided on a base 51 that houses a drive system, and two end effectors on the tip side of the robot arm 52. 55. The robot arm 52 is composed of a first arm 57 and a second arm 58 connected as a link mechanism. The two end effectors 55 are fixed to face the end effector base 56. The end effector base 56 is rotatably provided at the tip of the second arm 58, and is rotatably fixed to a rotary shaft of a rotary head 59 having a predetermined inclined surface. The end effector base 56 has a rotary shaft 54 that forms an angle θ with respect to the horizontal plane.
It is fixed rotatably around the center axis. As a result, the two end effectors 55 facing each other are rotated so that the substrate mounting surface is in contact with the conical side surface having the apex angle 2θ by the rotation of the end effector base 56. As a result, the wafer W attracted to the end effector 56 is held by the end effector 55 in the upright state as illustrated in accordance with the rotation of the end effector base 56. In this way, in the substrate transfer device 50, the end effector 55 turns while drawing a three-dimensional orbit, so that the horizontal projection area can be reduced.

[0005]

By the way, in the substrate transfer apparatus 50 shown in FIG. 10, two end effectors 5 are provided.
Since 5 is fixed to the end effector base 56 so as to form a straight line, a solid orbit is always drawn integrally with the rotation of the end effector base 56 so as to be in contact with the conical side surface 60. Two end effectors 55
Since the mounting angle of is fixed, each end effector 55
The relative position of cannot be changed. Therefore, when the wafer W or the like is transferred at a predetermined transfer position in the apparatus by the end effector 55, the end effector 55 on the opposite side is always provided.
Stands upright. For this reason, the wafer W adsorbed to the tip of the end effector 55 must be rotated more than necessary, which causes a problem that the transfer time of the wafer W becomes longer than necessary.

Therefore, an object of the present invention is to solve the above-mentioned problems of the conventional technique and to realize an independent transfer operation of the end effector so that the time for transferring the substrate in the apparatus can be shortened. It is to provide a transfer robot.

[0007]

In order to achieve the above object, the present invention provides a chuck rotation drive head rotatably supported by a tip rotation shaft of a robot arm, and a plurality of chuck rotation drive heads housed in the chuck rotation drive head. Of the drive source and the rotational forces transmitted from the output shafts of the plurality of drive sources, the end effector pivots around each rotation axis orthogonal to an inclined surface formed on one surface of the outer surface of the chuck rotation drive head. A plurality of substrate holding chucks each having a plurality of substrate holding chucks, and a substrate holding chuck that attracts a substrate to the end effector tip and / or a substrate holding chuck that does not attract a substrate by the independent or synchronous rotation operation of a drive source corresponding to each substrate holding chuck The position control of the end effector is performed.

At this time, all of the plurality of substrate holding chucks are position-controlled so that the end effector can hold the substrate transfer position which is a horizontal plane during the turning operation, and the substrate transfer operation is performed at this position. Is preferred.

Alternatively, the plurality of substrate holding chucks are
It is also preferable that the end effectors form horizontal planes having different heights when they are held at the substrate transfer position which is a horizontal plane during the turning operation.

As another invention, a chuck rotation drive head rotatably supported by a tip rotation shaft of a robot arm, a drive source housed in the chuck rotation drive head, and an output shaft of the drive source. By the transmitted rotational force,
A plurality of substrate holding chucks each having an end effector that pivots about each rotation axis orthogonal to an inclined surface formed on one surface of the outer surface of the chuck rotation drive head, and the rotation axes of the plurality of substrate holding chucks are synchronized. It is characterized in that the position control of the end effector is performed by rotating the end effector of the substrate holding chuck that adsorbs the substrate at the tip of the end effector and / or the substrate holding chuck that does not adsorb the substrate.

At this time, it is preferable that any of the plurality of substrate holding chucks can hold a substrate transfer position which is a horizontal plane during the turning operation of the end effector, and the substrate transfer operation is performed at this position.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a substrate transfer robot of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a side view showing the entire substrate transfer robot 1 of the present invention, and FIG. 2 is a robot arm 5 and a substrate holder 10.
FIG. 3 is an explanatory view showing the configuration of FIG.

As shown in FIG. 1, a substrate transfer robot 1 according to the present invention has a vertically-oriented rectangular parallelepiped box-shaped arm drive base 2 in which the first rotation axis (not shown) is used as a drive axis at the center of the upper surface. It is composed of one arm 3, a second arm 4 rotatably connected to the other end of the first arm 3, and a substrate holding portion 10 provided at the tip of the second arm 4. The substrate holding unit 10 further includes the chuck rotation drive head 20.
And two substrate holding chucks 30 mounted so as to be rotatable around _two rotational axes R ₁ and R ₂ that extend obliquely from above the inclined surface portion 21 of the chuck rotation drive head 20 (FIG. 2). reference). As the arm drive base, various types such as a cylindrical shape can be adopted in consideration of the internal housing mechanism, the installation space, and the like.

[Structure and Operation of Robot Arm] First, the robot arm 5 (first arm 3, which is a structure for supporting the substrate holding unit 10 according to the present invention and moving the substrate holding unit 10 along a predetermined locus in a horizontal plane). The configuration and operation of the second arm 4) will be described. Each of the arms 3 and 4 of the substrate transfer robot 1 shown in FIG. 1 is a swing arm having an aluminum jacket, and is rotated by a drive motor (not shown) installed at the bottom of the arm drive base 2 2 A predetermined rotation operation is provided by the drive shafts 6 and 7 arranged coaxially with the book. Two drive shafts 6,
The first drive shaft 6 of No. 7 is made of a solid steel rod, and the second drive shaft 7 having a hollow tube shape has a predetermined clearance with the first drive shaft 6 so as to accommodate the first drive shaft 6 therein. Are arranged coaxially. Therefore, the rotation of the first drive shaft 6 is directly transmitted to the first arm 3 rotatably supported by the arm drive base 2, and the first arm can be swung according to the rotation angle of the first drive shaft 6. Has become. As the arm material, various alloy materials such as stainless steel can be used in addition to aluminum.

Regarding turning of the second arm 4, a timing pulley (not shown) fixed to the upper end of the second drive shaft 7
A timing belt B is stretched in the first arm 3 with one end as the one end and a rotation shaft (not shown) of the second arm 4 as the other end. Therefore, the first arm 3 is rotated by the rotation of the first drive shaft 6 unrelated to the second drive shaft 7, and the pulley (not shown) internally fixed to the second drive shaft 7 causes the timing belt B to pass through. By rotating the rotary shaft 8 of the second arm 4 located at the other end, the second arm 4 can be rotated in the opposite direction by a double angle at a ratio of 1: 2 with respect to the rotation of the first arm 3. Further, a timing pulley (not shown) for belt-driving the chuck rotation drive head 20 at the tip of the second arm 4 is fixed to the first arm 3 on the outer side of the rotation shaft 8 of the second arm 4, and the second arm is provided. 4 is arranged independently of the rotary shaft 8. The rotation of this timing pulley rotates the tip rotation shaft 9 of the second arm 4 via the timing belt B housed in the second arm 4, and the chuck rotation drive head 20 attached to this tip rotation shaft 9 causes the arm to rotate. Rotate at the tip.

[Structure of Substrate Holding Unit] The substrate holding unit 10 is
The end effector 32 is composed of a substrate holding chuck 30 that sucks and holds the substrate W at the tip position, and a chuck rotation drive head 20 that supports the substrate holding chuck 30 and that rotates and rotates itself. Hereinafter, the substrate holding unit 1
The overall configuration and internal configuration of 0 will be described. It should be noted that the description will be made by classifying into an independent drive type and an interlocking drive type depending on the difference in the drive type by the drive motor in the chuck rotation drive head.

(Independent drive type) The independent drive type substrate holding section 10 has a structure in which two substrate holding chucks 30 attached to the chuck rotation drive head 20 can be independently driven by different drive motors. .

The chuck rotation drive head 20 is a head which is horizontally rotatable in a controllable manner by rotationally driving the tip rotation shaft 9 of the second arm 4. As is clear from FIGS. 1 and 2, a part of the upper surface is horizontal. On the other hand, a rectangular parallelepiped block having an inclined surface portion 21 cut at an angle of θ is formed.
The arm 4 is rotatably supported by the tip rotation shaft 9.
In this embodiment, the slope portion is set to θ = 45 °. At this time, in the present embodiment, the surface on which the substrate transfer robot 1 holds and transfers the substrate W (the substrate transfer surface) is a horizontal plane, and as shown in FIG. 1, it is orthogonal to the plane including the inclined surface portion 21. The perpendicular line forms θ with respect to the substrate transfer surface. This time, the substrate holding chuck 30 drive motor (to be described later) accommodated in the chuck rotary drive head 20 to have an output shaft of the parallel axes to the perpendicular to the rotational axis R _i, the axis of rotation R _i It turns around. That is, in FIG. 2, each of the independent drive type substrate holding chucks 30 forms a rotation axis R parallel to the substrate transfer surface, which is a horizontal plane, at an angle D and in parallel at a distance D.
It is possible to independently turn around ₁ and R _{2 in} either direction. The phase difference at the initial position of the two substrate holding chucks 30 is set to 180 ° in this embodiment. Further, in this turning operation, each substrate holding chuck 30 can be stopped with high precision on the substrate transfer surface which is a horizontal plane by the position control by the control unit (not shown), and its position can be held. In this state, the robot arm 5 can move along a predetermined trajectory along a bending and turning motion in the horizontal plane.

A substrate holding chuck 30 of the same shape, which is arranged at a distance D on the slope 21 of the jacket of the chuck rotary drive head 20, has a thick base 31 bent at a predetermined angle so as to form a substantially V shape. The processed aluminum material has a shape in which the flat end effector 32 is integrally formed. Alternatively, a wall thickness base and an end effector may be manufactured as assembly parts and assembled in parallel with the internal piping and wiring.

The wall thickness base 31 has a rigidity such that a rotary motion imparted from an output shaft of a drive motor, which will be described later, via a drive transmission portion is surely transmitted, and a connection portion 31 a with the chuck rotation drive head 20. The peripheral portion of the is finished in a semicircular shape so that the adjacent thick bases 31 do not interfere with each other.

The end effector 32 is a plate material processed product, and has a suction head 33 formed at the tip thereof, and is connected to the end of a suction pipe (not shown) piped in the end effector 32. A contact sensor (not shown) for detecting the substrate holding state is built in near the suction head 33. The substrate suction function at the position of the suction head 33 is set to such an extent that the substrate held by the substrate holding chuck 30 can be securely held without being displaced even when the substrate holding chuck 30 is rotated and is in an upright state as described later. ing.

FIGS. 3 and 4 show the end of the substrate holding chuck 30.
Substrate W (W ₁, W₂) Held
It is an operation state diagram showing a substrate transport state. Figure 3
The substrate holding chuck 30 of the clear substrate transfer robot 1
It is stored in a cassette (not shown) by the hand-effect unit 32.
The contained substrate W₁Adsorb and hold the
FIG. 8 is an operation state diagram showing a process of transporting to the. Figure 4 shows
Substrate W from plate removal state₁Substrate holding
Rotate axis 30₁(Fig. 2) Around arrow A
Rotate 90 ° and use another substrate holding chuck 30
Next substrate W₂The operation status showing that the
It is a state diagram. At this time, the substrate holding chuck is taken out first.
Substrate W adsorbed on 30₁Tilted as shown in FIG.
State, the robot arm 5 is held in a horizontal plane for a predetermined period of time.
Other than being located in the substrate transfer plane when bent and rotated along the path
Hold in a position that does not interfere with the trajectory of the board
Has been done.

FIGS. 5A and 5B are a side view and a front view in which a part of the casing is removed to explain the internal structure of the independently driven chuck rotary drive head 20. Figure 5
As shown in (a), two drive motors 22 for independently driving the two respective substrate holding chucks 30 are fixedly housed in the chuck rotation drive head 20 on a fixed mount (not shown). The drive motor 22 has an output shaft 22.
It is fixed to the fixed mount so that a is parallel to a perpendicular line orthogonal to the plane including the inclined surface portion 21. While the pulley 23 is fixed to the output shaft 22a, the pulley 25 is fixed to the rotary shaft 24 of the substrate holding chuck 30 which is parallel to the axis of the output shaft 22a, and the timing belt 26 is provided between the pulleys 23 and 25. It has been passed over. Therefore, the rotation of each drive motor 22 can impart a predetermined turning motion to the corresponding substrate holding chuck 30 by this belt transmission. Therefore, when the two substrate holding chucks 30 are attached, a predetermined phase difference of, for example, 180 ° is generated between the two substrate holding chucks 30, and the synchronous turning operation is performed by holding this phase difference.
The position control of the end effector 32 can be performed by independently rotating the drive motor 22 so as to change the phase difference between the respective end effectors 32.

For example, at a predetermined substrate transfer position, 2
In the case of continuous suction of substrates with a book end effector, the end effector that has already sucked and held the substrate swivels at a slight angle while the other end effector that does not suck the other substrate is moving to the substrate transfer position. Simply by doing so, interference with other end effectors can be avoided. Therefore, the operation time of the end effector for transferring the substrate can be significantly reduced. The installation position of the drive motor 22 and the orientation of the output shaft can be appropriately set according to the shape and space of the chuck rotation drive head 20. At that time, it is preferable to provide a transmission mechanism for smoothly transmitting the rotational force of the output shaft 22a to the rotational shaft 24 of the substrate holding chuck 30.

(Interlocking drive type) FIG. 6 shows the internal structure of the interlocking drive type chuck rotary drive head 20 in which two substrate holding chucks 30 are interlocked and synchronously rotated by one drive motor 22. It is a side view and a front view. A timing pulley 28 having the same diameter is attached to the rotary shaft 27 of each substrate holding chuck 30, and the rotary shafts 27 and 27 are synchronously rotated by a timing belt 29A hung on the timing pulley 28. ing. That is, the timing belt 29B is stretched between the timing pulley 23 fixed to the output shaft 22a of the drive motor 22 housed in the chuck rotary drive head 20 and the timing pulley 28 attached to the rotary shaft 27. The motor 22 is rotated, and the two substrate holding chucks 3 via the timing pulleys 29B and 29A.
The 0 rotation shaft 27 can be rotated in the same direction by the same angle. At this time, since the substrate holding chucks 30 are fixed to the rotating shafts 27 with a predetermined phase difference, the synchronous rotation can be realized while holding the phase difference. In the present embodiment, the phase difference is set to 180 °, but as shown in FIG. 7, when the interlocking turning is performed, the possible angle that can avoid the interference between the end effectors 32 holding the substrate is, for example, the end. The angle (phase difference) formed by the effector 32 may be set to 90 °. This angle is determined by the chuck rotation drive head 20 of the substrate holding chuck 30.
It can be easily handled by just adjusting the mounting angle.

(Modification of Independent Drive Type) In this modification, two drive motors can drive the respective substrate holding chucks 30 independently of each other as in the independent drive type described above. As shown in FIGS. 8 and 9, when the end effectors 32 are in the same phase at the substrate transfer position on the horizontal plane, the thickness of the thick base portion is changed so as to be separated by p in the horizontal height. A holding chuck 30 is used. With such a structure, the substrate stored in the cassette or the like can be continuously sucked by the other substrate holding chuck 30 while the substrate is sucked and held by the end effector 32 of the one substrate holding chuck 30. . For example, as shown in FIG. 9, even when the two substrate holding chucks 30 are in a state where they are arranged side by side with no phase difference and are at the substrate transfer position on the horizontal plane, the respective substrate holding chucks 30 can hold the substrates by suction. be able to.

Needless to say, in the above-described modified examples of the interlocking drive type and the independent drive type, both the substrate suction means and the substrate position detecting means have the same configuration as the independent drive type.

[0028]

As described above, according to the present invention,
Multiple end effectors attached to the robot arm can be independently swiveled in a predetermined sequence, so that end effectors can operate in parallel during substrate transfer, and the range where interference between end effectors is avoided Since the swiveling operation can be performed, it is possible to significantly reduce the substrate transfer time.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an embodiment of a substrate transfer robot according to the present invention.

FIG. 2 is a partial perspective view showing the configurations of a robot arm and a substrate holding unit of the substrate transfer robot of the present invention.

3 is a partial perspective view showing a state where a substrate is held by the substrate holding chuck shown in FIG.

FIG. 4 is a partial perspective view showing a state where the substrate holding chuck shown in FIG. 2 holds a substrate in a position-controlled state.

5A and 5B are a partially exploded plan view and a side view showing an overall configuration of a substrate holding unit (independent drive type) and an internal configuration of a chuck rotation drive head.

6A and 6B are a partially exploded plan view and a side view showing an overall configuration of a substrate holding unit (interlocking drive type) and an internal configuration of a chuck rotation drive head.

7A and 7B are a partial exploded plan view and a side view showing a modified mounting example of a substrate holding chuck in the substrate holding unit (interlocking drive type) shown in FIG.

8A and 8B are a partial exploded plan view and a side view showing a modification of mounting the substrate holding chuck in the substrate holding unit (independent drive type) shown in FIG.

9 is a partial perspective view showing a mounting state of the substrate holding chuck shown in FIG. 8 at a substrate transfer position.

FIG. 10 is a perspective view showing a configuration of an example of a conventional substrate transfer robot.

[Explanation of symbols]

1 Substrate Transfer Robot 3 First Arm 4 Second Arm 5 Robot Arm 9 Second Arm Tip Rotational Shaft 10 Substrate Holding Unit 20 Chuck Rotation Drive Head 21 Slope 22 Drive Motor 22a Output Shaft 27 Rotational Shaft 30 Substrate Holding Chuck 31 Thickness base 32 End effector D Interval R _i Rotation axis W _i Substrate

Claims (5)

[Claims] 1. A chuck rotary drive head rotatably supported by a tip rotary shaft of a robot arm, a plurality of drive sources housed in the chuck rotary drive head, and output shafts of the plurality of drive sources. A plurality of substrate holding chucks each having an end effector that swivels around each rotation axis orthogonal to an inclined surface formed on one surface of the outer cover of the chuck rotation drive head by the transmitted rotational force; The position control of the end effector of the substrate holding chuck that adsorbs the substrate to the tip of the end effector and / or the substrate holding chuck that does not adsorb the substrate is performed by the independent or synchronous rotation operation of the drive source corresponding to Substrate transfer robot. 2. The position control of any of the plurality of substrate holding chucks is performed so that the end effector can hold a substrate transfer position which is a horizontal plane during the turning operation, and the substrate transfer operation is performed at the position. The substrate transfer robot according to claim 1. 3. The plurality of substrate holding chucks form horizontal planes having different heights when the end effectors are held at the substrate transfer positions which are both horizontal planes during the turning operation. The substrate transfer robot according to claim 1 or 2. 4. A chuck rotation drive head rotatably supported by a tip rotation shaft of a robot arm, a drive source housed in the chuck rotation drive head, and an output shaft of the drive source. A plurality of substrate holding chucks each having an end effector that swivels around each rotation axis orthogonal to an inclined surface formed on one surface of the outer cover of the chuck rotation drive head by a rotational force; Rotate the rotation axis synchronously,
A substrate transfer robot, characterized in that the position control of the end effector is performed by interlockingly swinging an end effector of a substrate holding chuck that adsorbs a substrate at the tip of the end effector and / or a substrate holding chuck that does not adsorb the substrate. 5. The substrate holding chuck according to claim 4, wherein any of the plurality of substrate holding chucks can hold a substrate transfer position which is a horizontal plane during the turning operation of the end effector, and performs the substrate transfer operation at this position. The substrate transfer robot described in 1.