JP2002270674A - Unloading device - Google Patents

Abstract

(57) [PROBLEMS] To carry out a plate-like object such as a semiconductor wafer from a cassette without damaging the plate-like object even when the plate-like object is not stored horizontally, and Work without delay. SOLUTION: An unloading device 10 for unloading a plate-like object stored in a cassette 30 includes at least a holding unit 11 for sucking and holding the plate-like object, and a bending arm 16 for inserting the holding unit 11 into the cassette. , The holding portion 11 has a first support portion 20 and a second support portion 21 for supporting the plate-like material, and the first support portion 20 and the second support portion 21 A first detection sensor 24 and a second detection sensor 25 for detecting the accommodated plate-like object are provided, respectively, and when the plate-like object is not housed horizontally, the state is detected, and a holding unit is appropriately provided. By rotating the bending arm 11 about the direction of movement of the bending arm 16 as a rotation center, the plate-shaped object is reliably held and carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unloading device for unloading a plate-like object such as a semiconductor wafer housed in a cassette.

[0002]

2. Description of the Related Art A back surface of a semiconductor wafer having a plurality of circuits such as ICs and LSIs formed on a front surface is ground to a predetermined thickness by using, for example, a grinding device 40 shown in FIG.

The grinding device 40 carries out a cassette 30 for accommodating semiconductor wafers before grinding and a semiconductor wafer 31 for accommodating semiconductor wafers after grinding, and carries out semiconductor wafers from the cassette 30 or carries semiconductor wafers into the cassette 31. The unloading device 41, the centering table 42 for aligning the semiconductor wafer at a predetermined position, the first and second transfer means 43 and 44 for transferring the semiconductor wafer W, and the semiconductor wafer is suction-held on the upper part. A turntable 49 having four chuck tables 45, 46, 47, 48, grinding means 50, 60 for grinding the semiconductor wafer W held on each chuck table, and a cleaning means 61 for cleaning the semiconductor wafer after grinding. And

As shown in FIG. 5, a plurality of semiconductor wafers W1, W2,... Before grinding are accommodated in a cassette 30, and are picked up one by one by an unloading device 41 shown in FIG. It is placed on the table 42. After the alignment of the semiconductor wafer W is performed on the centering table 42, the first transfer means 43
The semiconductor wafer W is attached to the chuck table 46 located at the same position as the position of the chuck table 45 by the first transfer means 43 being swiveled while being sucked.
Is placed.

Next, the turntable 49 is rotated by a required angle (90 degrees in the illustrated example) to rotate the chuck table 46.
Is positioned immediately below the grinding means 50.

The grinding means 50 is connected to a slide part 51, and is guided by a guide rail 52 provided in a vertical direction. The slide part 51 is driven by a pulse motor 53 and moves up and down. Also move up and down.

In the grinding means 50, the driving source 5
A grinding wheel 57 is mounted via a mounter 56 on the tip of a spindle 55 connected to the spindle 4 and disposed vertically, and a grinding wheel 58 for rough grinding is fixed to a lower portion of the grinding wheel 57. The grinding wheel 58 is driven by the drive source 54 and the spindle 55 rotates.
The grinding means 50 descends while rotating, and the rotating grinding wheel 58 contacts the back surface of the semiconductor wafer W to grind the back surface.

At this time, the chuck table 45 is automatically positioned at the position where the chuck table 46 was located before the rotation of the turntable 49. And
The semiconductor wafer to be ground next is unloaded from the cassette 30 and placed on the centering table 42, and after being aligned, is transported to the chuck table 45 by the first transporting means 43 and placed thereon.

After the rough grinding, the semiconductor wafer W held on the chuck table 46 is positioned immediately below the grinding means 60 by rotating the turntable 49 by a required angle, and is disposed on the grinding wheel 59 of the grinding means 60. The back surface is subjected to finish grinding by the action of the grinding wheel 61 for finished grinding. On the other hand, the semiconductor wafer held on the chuck table 45 is positioned immediately below the grinding means 50,
Here, rough grinding is performed under the action of the grinding means 50.

As described above, the semiconductor wafers are sequentially taken out of the cassette 30, the semiconductor wafers are suction-held on the respective chuck tables, and the turntable 49 is subjected to the action of the grinding means 50, 60 while intermittently rotating, thereby successively. The back surface of the semiconductor wafer is being ground.

Then, the semiconductor wafer after the finish grinding is transported to the cleaning means 62 by the second transport means 44, and after being cleaned, is stored in the cassette 31 by the unloading device 41. Thus, all the semiconductor wafers W after the grinding are stored in the cassette 31.

[0012]

As shown in FIG. 5, semiconductor wafers W1 and W
A plurality of support grooves 32 for supporting the end portions of 2,... Are formed, and the opposing support grooves 32 on both sides are respectively located at the same height, and the two support grooves 32 at the same height are formed.
Semiconductor wafers W1, W2, as supported by
Are individually accommodated, the individual semiconductor wafers W
Are supported in a horizontal state as shown in FIG. If all the semiconductor wafers W are stored in a horizontal state, the unloading from the cassette 30 can be performed smoothly and safely.

However, in practice, for example, as shown in FIG. 6, the semiconductor wafers W1 and W2 are supported by supporting grooves having different heights and are accommodated in a state where they are not horizontal. When trying to carry out the wafers W1 and W2, the ends may come into contact with the support grooves 32 and be damaged. Further, a series of operations in the grinding device 40 may be interrupted due to the end portion being caught at the time of carrying out, and the productivity may be reduced.

Therefore, when a plate-like object such as a semiconductor wafer is carried out of the cassette, even if the plate-like object is not stored horizontally, the plate-like object is carried out without being damaged, and the whole work is hindered. There is a problem to do without.

[0015]

SUMMARY OF THE INVENTION As a specific means for solving the above-mentioned problems, the present invention relates to an unloading device for unloading a plate-like object accommodated in a cassette, wherein the holding device sucks and holds the plate-like object. Part, and at least a bending arm for inserting the holding part into the cassette, the holding part has a first support part and a second support part for supporting the plate-like material, a first support part and An unloading device provided with a first plate-like object detection sensor and a second plate-like object detection sensor for detecting a plate-like object housed in a cassette is provided on the second support portion.

In this carrying-out device, the holding portion is constituted so as to be rotatable by a required angle about the advance / retreat direction of the bending arm, and one plate detection sensor detects the plate and the other plate detection sensor If the plate does not detect the plate, rotate the holder until the other plate sensor detects the plate, and the holder inserted into the cassette rises relative to the cassette. The two plate-shaped object detection sensors confirm the presence of the plate-shaped object, suction-hold the plate-shaped object, and carry out the plate-shaped object from within the cassette, the first plate-shaped object detection sensor and the second An additional requirement is that the plate-like object detection sensor is an electrostatic detection sensor that detects the presence of a plate-like object by a change in capacitance.

According to the carrying-out device configured as described above,
The plate-like object is not horizontal because a plate-like object detection sensor is provided on each of the first support portion and the second support portion, and the presence of the plate-like object can be detected by both plate-like object detection sensors. If it is stored in a cassette, it can be confirmed.

Further, the holding portion is rotatable by a required angle about the direction of advance and retreat of the bending arm. If the presence of a plate-like object cannot be detected, the holding unit is rotated to make the holder parallel to the plate-like object, and then the plate-like object can be held and carried out of the cassette. Can be carried out smoothly even when the is stored in the cassette in a state where it is not horizontal.

Further, when the capacitance sensor is used as the plate-like object detection sensor, erroneous recognition is eliminated, and the plate-like object can be reliably detected.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described by taking a carry-out device 10 shown in FIG. 1 as an example. The unloading device 10 includes a holding unit 11 that holds a plate-like object, a rotation driving unit 12 that drives the holding unit 11 to rotate about an X-axis direction that is an advancing and retreating direction, a first arm 13 and a second arm 14, A bending arm 16 comprising a first arm turning means 15 for connecting these and turning the first arm 13;
Second arm turning means 1 for turning the second arm 14
7 and a vertical moving means 18 for driving the bending arm 16 in the vertical direction.

The holding portion 11 is formed in a flat shape, and has a base portion 19.
, The first support portion 20 and the second support portion 21 project in the same direction, and a plate-like material is suctioned on the surfaces of the first support portion 20 and the second support portion 21. A first suction unit 22 and a second suction unit 23 to be held are provided, and a first plate-like object detection sensor 24 and a second plate-like object detection sensor 25 are provided.

The end of the base 19 of the holding unit 11 is connected to, for example, a pulse motor provided inside the rotary drive unit 12, and can be rotated about the X-axis direction by the drive of the pulse motor. It has become.

The holding unit 11 and the rotation driving unit 12
The first arm 13 is driven by the first arm rotating means 15
Is pivoted and the second arm 14 is driven by the second arm pivoting means 17 to pivot, and the vertical movement of the bending arm 16 by the vertical movement means 18 allows the second arm 14 to be positioned at a desired position and height.

As the first plate-like object detection sensor 24 and the second plate-like object detection sensor 25, for example, the capacitance changes when the plate-like object approaches, and the presence of the plate-like object is determined based on the change. An electrostatic detection sensor for detecting can be used. In addition, a photosensor including a pair of a light emitting element and a light receiving element such as a photocoupler can be used, but in this case, erroneous recognition may occur due to surface luminance or scattered light of the plate-like object. It is desirable to use an electrostatic detection sensor that can reliably detect the presence of a plate-like object without any problem.

When unloading the semiconductor wafers stored in the cassette 30, the semiconductor wafers are sequentially unloaded from the lowermost semiconductor wafer and finally the uppermost semiconductor wafer is unloaded. In some cases, a desired semiconductor wafer is carried out. First, as shown in FIG. 2A, the holding unit 1 is driven by the driving of the up / down moving means 18 shown in FIG.
1 is positioned horizontally below the semiconductor wafer W1 to be unloaded.

Then, as shown in FIG. 2B, the first arm 13 and the second arm 14 are turned by the first arm turning means 15 and the second arm turning means 17 shown in FIG. To move the holding portion 11 in the + X direction and to enter below the semiconductor wafer W.

Next, the first plate detecting sensor 24 and the second plate detecting sensor 25 detect the presence of the semiconductor wafer W1 by raising the holding portion 11 by driving the vertical moving means 18. . At this time, when the first plate-like object detection sensor 24 and the second plate-like object detection sensor 25 simultaneously detect the presence of the semiconductor wafer W1, it is the case where the semiconductor wafer W1 is stored horizontally.

When the first plate-like object detection sensor 24 and the second plate-like object detection sensor 25 simultaneously confirm the presence of the semiconductor wafer W1 in this manner, as shown in FIG. Further, the semiconductor wafer W is mounted on the holding unit 11 by slightly raising the holding unit 11. Then, the semiconductor wafer W1 is suction-held by the first suction unit 22 and the second suction unit 23, and the first arm 13 and the second arm 14 are retracted in the −X direction as shown in FIG. Then, the semiconductor wafer W is held together with the holding portion 11.
Out.

On the other hand, when the first plate-like object detection sensor 24 and the second plate-like object detection sensor 25 cannot simultaneously confirm the presence of the semiconductor wafer W, as shown in FIG. This is the case where W1 is stored in a non-horizontal state. In this case, when the presence of the semiconductor wafer W1 is confirmed by the first plate-like object detection sensor 24, the raising of the holding unit 11 is stopped, and the vertical rotation driving unit 12 drives the holding unit 11 to move the bending arm 16 forward and backward. X which is the direction
With the axial direction as the center of rotation, until the presence of the semiconductor wafer W1 can be confirmed by both plate-like object detection sensors, that is, as shown in FIG.
Are rotated in the direction in which the second plate-like object detection sensor 25 moves up until the position becomes parallel.

Then, the first plate-like object detection sensor 24 and the second plate-like object detection sensor 25 are connected to the semiconductor wafer W1.
The rotation of the holding unit 11 is stopped when the existence of
As shown in (C), the semiconductor wafer W1 is placed by raising the holding unit 11, and the semiconductor wafer W is suction-held, and the first arm 13 and the second arm 14 are retracted in the -X direction. The wafer W is unloaded.

As described above, even when the semiconductor wafer is accommodated in a non-horizontal state, the semiconductor wafer is accommodated in such a state by using the first plate-like object detection sensor 24 and the second plate-like object detection sensor 25. After confirming that the semiconductor wafer has been rotated, the semiconductor wafer can be reliably suction-held and carried out while the holding unit 11 is parallel to the semiconductor wafer.

Therefore, unlike the related art, the end of the semiconductor wafer does not come into contact with the support groove of the cassette and is damaged, and the unloading operation is not interrupted and the productivity is not reduced.

If a monitor 26 is connected to the unloading device 10 as shown in FIG.
Alternatively, the result of the determination of the presence or absence of the semiconductor wafer W by each of the second plate-like object detection sensors 25 can be displayed on the monitor 26. For example,
When the determination results of the first plate-like object detection sensor 24 and the second plate-like object detection sensor 25 are the same, "OK" is displayed,
If the judgment result is different, "NG" is displayed, so that the operator can easily know whether or not the semiconductor wafer is stored horizontally. In the case of "NG", it is desirable to emit a warning sound so as to surely notify the operator.

In this embodiment, the case where the semiconductor wafer is carried out has been described as an example. However, the present invention can be applied to a plate-like object other than the semiconductor wafer.

[0035]

As described above, according to the unloading device according to the present invention, the plate-like object detection sensors are provided on the first support portion and the second support portion, respectively. Since the presence of the plate-like object can be detected by the sensor, when the plate-like object is stored in the cassette in a non-horizontal state, it can be confirmed, and the plate-like object is not damaged.

Further, the holding portion is rotatable by a required angle about the advance / retreat direction of the bending arm, and the plate-like object is accommodated in the cassette in a non-horizontal state, and only one plate-like object detection sensor is used. If the presence of the object cannot be detected, the holding unit is rotated so that the holding unit is parallel to the plate, and the plate can be held and carried out of the cassette. Can be carried out smoothly even when the sheet is stored in a cassette in a state where it is not horizontal, and the productivity is not hindered.

Further, when a capacitance sensor is used as the plate-like object detection sensor, erroneous recognition is eliminated, and the plate-like object can be reliably detected, so that the reliability is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of a carry-out device according to the present invention.

FIG. 2 is an explanatory view showing a procedure for unloading a semiconductor wafer from a cassette using the unloading device.

FIG. 3 is an explanatory view showing a procedure for unloading a semiconductor wafer stored in a cassette in a non-horizontal state using the unloading device.

FIG. 4 is a perspective view showing a grinding device as an example of a device on which the unloading device is mounted.

FIG. 5 is a front view showing a state where semiconductor wafers are stored in a cassette in a horizontal state.

FIG. 6 is a front view showing a state where semiconductor wafers are stored in a cassette in a non-horizontal state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Unloading device 11 ... Holding part 12 ... Rotation drive part 13 ... First arm 14 ... Second arm 15 ... First arm turning movement means 16 ... Bending arm 17 ... Second arm turning movement means 18 ... Vertical movement means 19 ... Base 20: first support 21: second support 22: first suction unit 23: second suction unit 24: first plate-like object detection sensor 25: second plate-like object detection sensor 26 ... Monitors 30, 31 ... Cassette 32 ... Support groove 40 ... Grinding device 41 ... Unloading device 42 ... Centering table 43 ... First conveying means 44 ... Second conveying means 45, 46, 47, 48 ... Chuck table 49 ... Turntable 50, 60 ... Grinding means 51 ... Slide part 52 ... Guide rail 53 ... Pulse motor 54 ... Drive source 55 ... Spindle 56 ... Mounter 57 ... Grinding wheel 58 ... Grinding grindstone 59: grinding wheel 61: grinding wheel 62: cleaning means

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F031 CA02 FA01 FA11 FA12 FA14 FA15 GA08 GA36 GA43 GA47 JA06 JA09 JA13 JA17 JA23 JA25 LA07 MA22 MA23 PA20

Claims (4)

[Claims] 1. An unloading device for unloading a plate-like object stored in a cassette, comprising at least a holding unit for sucking and holding the plate-like object, and a bending arm for inserting the holding unit into the cassette. The holding portion has a first support portion and a second support portion for supporting the plate-like material, and the first support portion and the second support portion are accommodated in the cassette. An unloading device provided with a first plate-shaped object detection sensor and a second plate-shaped object detection sensor for detecting a plate-shaped object. 2. The holding section is configured to be rotatable by a required angle about a direction in which the bending arm advances and retreats as a center of rotation. 2. The unloading device according to claim 1, wherein when the plate-shaped object is not detected, the holding unit is rotated until the other plate-shaped object detection sensor detects the plate-shaped object. 3. The holding portion inserted into the cassette rises relatively to the cassette, and the two plate detection sensors confirm the presence of the plate, and then hold the plate by suction. The unloading device according to claim 1, wherein the plate-like object is unloaded from the cassette. 4. The first plate-like object detection sensor and the second plate-like object detection sensor are electrostatic detection sensors that detect the presence of a plate-like object by a change in capacitance.
The unloading device according to item 1.