JPH0228030Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is a spinner table mechanism of a dicing saw, especially after cutting off the driving force of the drive motor.
The present invention relates to a spinner table mechanism for a dicing saw that rotates a spinner table using the driving force of a pulse motor.

[Conventional technology]

As is well known, wafer cutting using a dicing saw consists of the following steps.

First, as a pre-process, a wafer is attached to the center of a frame using adhesive tape, and a plurality of frames are housed in a cassette. The cassette is then placed at a predetermined position on the dicing saw.

In a dicing saw, first, a frame with wafers is taken out of a cassette and loaded. After the wafer is aligned on the micron order by optical means,
The frame is moved to the cut position. The wafer is then cut into chips by a diamond cutting wheel along the street. However, because the adhesive tape was not cut,
Even after being cut into chips, the wafer maintains its shape before being cut. Next, the frame is placed on a spinner table, and a drive motor, such as a DC motor, is activated to rotate the spinner table at low speed and spray a high-pressure water jet to clean the wafer. After that, the DC motor is switched to high speed rotation, and
Dry the wafer by blowing pressurized air. Finally, the frame is stored in the cassette and unloaded, thereby completing all steps in the dicing saw. The wafer cut into chips by the dicing saw leaves the dicing saw while being housed in a cassette, and is sent to the next continuous process, that is, the next assembly process.

The above loading in the dicing saw,
The processes of alignment, cutting, washing and drying, and unloading are performed continuously and automatically in the latest dicing saws. Here, alignment and cutting are performed on the order of microns, and it is necessary to suppress the generation of vibrations in other processes as much as possible so as not to adversely affect these processes. However, the steps are performed continuously, and in particular, the cleaning and drying step, which is most likely to generate vibrations, is performed adjacent to the alignment step and the cutting step. Therefore, considerations have been made in the past to prevent vibrations from occurring when the spinner table stops rotating. On the other hand, in order to automatically store the frame in the cassette after washing and drying, it is necessary to precisely control the stop position of the spinner table.

[Problem that the invention attempts to solve]

However, with the spinner table mechanism of a known dicing saw, it is difficult to suppress the generation of vibration and accurately control the stop position of the spinner table.

For example, as a known spinner table mechanism for a dicing saw, a configuration is known in which a leaf spring is attached to the lower surface of the spinner table and the leaf spring is brought into contact with a stopper to stop the spinner table. Here, after turning off the DC motor, the DC
Using the remaining power of the motor, the stopper is raised into the path of the leaf spring. In such a configuration, the spinner table rotating due to inertia comes into contact with the leaf spring and gradually stops. However, it is difficult to stop the spinner table in a predetermined position without generating any vibrations. Here, if a return prevention spring is provided adjacently, the return of the spinner table can be prevented, and if a leaf spring with a large spring constant is used, overshoot can be prevented. However, if a leaf spring with a large spring constant is used, the spinner table will come to a sudden stop, and vibrations will likely occur in the spinner table. Furthermore, in the above configuration using a leaf spring, the spinner table often stops before or after the leaf spring contacts the stopper.

The object of this invention is to provide a spinner table mechanism for a dicing saw that accurately stops the spinner table at a predetermined position without causing vibration.

[Means for solving problems]

To achieve this purpose, according to this invention,
A pulse motor is provided in addition to the drive motor, and after the driving force of the drive motor is cut off and the spinner table stops, the pulse motor rotates the spinner table. The detection target material is rotatably provided integrally with the spinner table. Further, the sensor detects that the object to be detected has reached a predetermined position after the driving force of the drive motor to the drive shaft is cut off, and generates a signal to cut off the driving force of the pulse motor to the drive shaft. There is.

[Effect]

With this configuration, the rotation angle of the pulse motor for each pulse, that is, the rotation angle of the spinner table, can be made sufficiently small. Therefore, even if the spinner table stops at any position when the driving force from the drive motor is cut off, the spinner table can be rotated in small increments and quickly to a predetermined position by the driving force of the pulse motor. Therefore, accurate positioning of the spinner table is possible. In addition, since the rotation angle of the spinner table for each pulse is small,
The spinner table does not stop abruptly. Therefore, no vibration occurs on the spinner table.

〔Example〕

Hereinafter, embodiments of this invention will be described in detail with reference to the drawings.

As shown in FIG. 1, a spinner table mechanism 10 of a dicing saw according to an embodiment of this invention
As in the conventional case, the spinner table 12 and
The drive motor that is the drive source for the spinner table,
For example, it is equipped with a DC motor 14. In addition,
An AC motor may be used as the drive motor.
The spinner table 12 is fixed to the upper end of a drive shaft 16, and by driving the drive shaft with the driving force of the DC motor 14, the spinner table rotates integrally with the drive shaft. The wafers 17 (see FIG. 3) cut by a cutting mechanism (not shown) located adjacent to the spinner table mechanism 10 are sequentially placed on the spinner table together with the frame 18 to be washed and dried. Typically, wafer 17 is attached to the center of frame 18 by adhesive tape. However, the wafer can be cut without a frame, and a frame is not necessarily required.

The spinner table mechanism 10 of this invention further includes a pulse motor 20, a slit disk 22 which is a material to be detected, and photointerrupters 24 and 25 which are sensors. The pulse motor 20 is arranged to transmit driving force to the drive shaft 16 via a clutch, such as an electromagnetic clutch 26. In this way, the pulse motor 20
In the configuration in which the shaft 16 can be rotated with the clutch 26 interposed, when the DC motor 14 rotates,
By disengaging the clutch, the pulse motor 2
0 remains stationary while the DC motor is rotating,
Destruction of the pulse motor is prevented. DC motor 1
4 is turned off and the output of the DC motor becomes zero,
When the clutch is connected, a pulse is supplied from a pulse generation circuit in the control device to start the pulse motor 20 and start the shaft 1.
Rotate 6 at low speed. Supplying and stopping the supply of pulses to the pulse motor 20 is controlled by a control device such as a central processing unit (CPU). The same control device starts, stops, and controls the DC motor 14.
It is also preferable to control operations such as clutch engagement. In the embodiment, the material to be detected is in the form of a slit disk 22 that is fixed to the drive shaft 16 and rotates integrally therewith. As can be clearly seen from FIG. 2, an extending portion 28 is formed on the side surface of the slit disk 22. The object to be detected is sufficient as long as it indicates the relative rotational position of the spinner table 12, and may be in a form other than a slit disk with an extension as shown in the figure, or may be directly attached to the spinner table. good. Furthermore, a notch or the like may be used instead of the extending portion. On the other hand, in relation to the material to be detected, a photointerrupter is employed as a sensor in the embodiment, and for reasons described later, a pair of photointerrupters 24 and 25 that operate alternately are arranged 180 degrees apart. .

After the drive motor is turned off, the sensor detects when the object to be detected reaches a predetermined position and sends a signal to cut off the drive force of the pulse motor to the drive shaft, for example, a pulse is supplied from a pulse generation circuit to the pulse motor. It is sufficient to have the function to generate a signal to stop the operation. And it goes without saying that sensors other than photointerrupters can be used. The sensor signal is sent to the control device, and the supply of pulses from the pulse generation circuit to the pulse motor 20 is immediately cut off, thereby stopping the pulse motor.

Note that cutting wafers with a dicing saw is one step in the continuous process of IC manufacturing.
In relation to the next process, the storage cassette that stores the wafers after being cut is currently placed opposite to the supply cassette that stores the wafers before being cut. Therefore, the spinner table is required to stop at a position rotated by 180 degrees after washing and drying compared to before washing and drying. In other words, the frame 18 moving in the direction of the arrow in FIG.
is, relative to the position before washing and drying shown in Figure 3A,
After washing and drying, it is rotated 180 degrees as shown in Figure 3B.

The spinner table mechanism 10 having the above configuration operates as follows.

When the DC motor 14 is turned off, the driving force transmitted from the DC motor to the drive shaft 16 is cut off.
The spinner table 12 stops at random positions. The DC motor 14 is turned off.
It is electrically detected when the voltage of the motor 14 becomes zero, and a pulse is supplied from the pulse generation circuit to start the pulse motor 20. The driving force of the pulse motor 20 is then transmitted to the drive shaft 16 via the electromagnetic clutch 26 to rotate the spinner table 12 little by little. The slit disk 22 also rotates together with the spinner table 12. When the voltage of the DC motor 14 becomes zero,
The photointerrupters 24 and 25 also operate, detecting that the slit disk 22 has reached a predetermined position, and generate a signal to cut off the driving force of the pulse motor 20 to the drive shaft 16. That is, when the extension 28 of the slit disk enters the photointerrupter and interrupts the light, the photointerrupter generates a signal that cuts off the supply of pulses from the pulse generation circuit to the pulse motor 20. By cutting off the supply of pulses, the pulse motor 24 stops, and the spinner table 12 also stops. The slit disk 22 is set so that the spinner table is located at a predetermined position when the extending portion 28 of the slit disk 22 is detected by a photointerrupter.
Therefore, the extending portion 28 of the slit disk is detected by the photointerrupter and the pulse motor 20 is
When the spinner table 12 stops, the spinner table 12 stops at a predetermined position.

Further, for example, assume that the frame 18 is placed on the spinner table at the position shown in FIG. 2, the right sensor is activated, the extension 28 is detected by this sensor, and the spinner table 12 is stopped. . Next, for the frame 18 sent, the right sensor, that is, the photointerrupter 2
If 5 is activated, the spinner table will stop at the same position as before rotation, and the frame cannot be stored in the storage cassette in that state. However, as mentioned above, in the embodiment, a pair of sensors are arranged 180 degrees apart, and these sensors are arranged to operate alternately. Therefore, another sensor, photointerrupter 24, is activated for the next frame 18, resulting in a 180° shift in the position of the spinner table before and after rotation. Therefore, after being washed and dried, the frames 18 that are sent sequentially are always positioned in a desired direction with respect to the storage frame, and can be easily stored in the storage frame. The configuration consists of a pair of sensors that operate alternately and are separated by 180 degrees.
This is only a practical preference given the current relative relationship between the supply frame and the storage frame. and,
The number, arrangement, etc. of sensors can be changed in response to variations in the relative relationship between frames.

[Effect of the invention] With this configuration, the rotation angle of the pulse motor for each pulse, that is, the rotation angle of the spinner table 12, can be set small, so that the rotation angle of the spinner table 12 can be set small in small steps and quickly no matter where the spinner table is stopped. The spinner table can be rotated. Therefore, the spinner table 12 can be positioned accurately. Furthermore, since the spinner table 12 is rotated in small increments, the spinner table does not stop abruptly and no vibration occurs. Therefore, there is no adverse effect on the adjacent cutting mechanism.

The above-mentioned embodiments are for illustrating this invention, and are not intended to limit this invention in any way, and any modifications, modifications, etc. made within the technical scope of this invention are also included in this invention. Needless to say.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a spinner table mechanism of a dicing saw according to an embodiment of the invention;
FIG. 2 is a plan view of the spinner table mechanism of the dicing saw taken along line - in FIG. 1;
The figure is an explanatory diagram showing the positional relationship of the frames before and after washing and drying. 10: spinner table mechanism of dicing saw, 12: spinner table, 14: DC motor (drive motor), 16: drive shaft, 18:
Frame, 20: Pulse motor, 22: Slit disk (detected material), 24, 25: Photointerrupter (sensor), 26: Electromagnetic clutch,
28: Extending portion of the slit disk.

Claims (1)

[Claims for Utility Model Registration] A spinner table on which a cut wafer is placed, a drive motor that rotates the spinner table by applying driving force to a fixed drive shaft of the spinner table, and a drive motor that is connected to the spinner table via a clutch. a pulse motor that is arranged to be able to drive a drive shaft of the drive shaft, and that transmits the drive force to the drive shaft via a clutch to rotate the spinner table after the drive force of the drive motor to the drive shaft is cut off; After the driving force of the drive motor to the drive shaft is cut off, the pulse motor detects that the detected material has reached a predetermined position, and then pulses are sent to the pulse motor. When the driving force of the drive motor is cut off, the clutch is connected and pulses are supplied to the pulse motor to start the pulse motor, and the signal from the sensor is A spinner table mechanism for a dicing saw, comprising: a control device for stopping the pulse motor by cutting off the supply of pulses when the pulse is received;