JP7832067B2 - Processing unit - Google Patents

Description

This invention relates to a processing apparatus for handling a frame having a central opening for housing wafers.

A wafer, in which multiple devices such as ICs and LSIs are formed on its surface, with device regions demarcated by planned division lines and an outer peripheral surplus region surrounding the device regions, is then ground on its back surface to the desired thickness. Afterward, it is divided into individual device chips using a dicing device or laser processing device, and each divided device chip is used in electrical equipment such as mobile phones and personal computers.

The applicant proposed a technique to facilitate the transport of ground wafers by leaving a ring-shaped reinforcing portion on the back surface corresponding to the excess outer region, performing a predetermined process, then attaching dicing tape to the back surface of the wafer and supporting the wafer with a frame, and finally removing the ring-shaped reinforcing portion from the wafer (see, for example, Patent Document 1).

However, the technology disclosed in Patent Document 1 presents problems with productivity, as it is difficult to attach dicing tape to the back surface of a wafer with a convex ring-shaped reinforcing portion formed on the back surface corresponding to the excess outer region, thereby integrating it with the frame, and it is also difficult to cut and remove the ring-shaped reinforcing portion from the wafer.

Therefore, the applicant has developed a processing apparatus for removing a convex ring-shaped reinforcing portion from a wafer in which a convex ring-shaped reinforcing portion is formed on the back surface corresponding to the excess outer region (see, for example, Patent Document 2).

This processing device,
A wafer cassette table on which a wafer cassette containing multiple wafers is placed,
A wafer unloading means for unloading wafers from wafer cassettes placed on a wafer cassette table,
A wafer table that supports the surface side of the wafer that has been unloaded by the wafer unloading means,
A frame housing means for housing multiple ring-shaped frames, each having an opening for housing wafers,
A frame unloading means for unloading frames from a frame storage means,
A frame table that supports the frame that has been removed by the frame removal means,
A tape application means is positioned above the frame table and is used to apply tape to the frame,
A tape-attached frame transport means that transports the frame with tape attached to it to a wafer table, positions the opening of the frame on the back surface of a wafer supported on the wafer table, and places the tape-attached frame on the wafer table.
A tape-pressing means for pressing the tape of a tape-attached frame onto the back surface of a wafer,
A frame unit unloading means for unloading a frame unit from a wafer table, in which the tape of the tape-attached frame and the back surface of the wafer are pressed together by a tape-pressure means,
A reinforcement removal means for cutting and removing a ring-shaped reinforcement from a wafer of a frame unit that has been unloaded by a frame unit unloading means,
A ringless unit removal means for removing the ringless unit, from which the ring-shaped reinforcing part has been removed, from the reinforcing part removal means,
The system includes a frame cassette table on which a frame cassette containing a ringless unit, which has been unloaded by a ringless unit unloading means, is placed.

Japanese Patent Publication No. 2010-62375 Japanese Patent Publication No. 2022-19392

However, the frame storage mechanism is designed to hold multiple frames, and the frames are discharged from an outlet at the top of the mechanism. This configuration presents a problem: if a frame that has warped beyond a certain threshold is transported to the frame table, the tape cannot be properly applied to that frame. Furthermore, since the frames are reused, adhesive residue from the dicing tape remains on the frames, causing the upper and lower frames to stick together and be discharged together.

The above-mentioned problem can occur not only in the processing apparatus disclosed in Patent Document 2, but also in processing devices equipped with frame storage means, which allows frames to be loaded and housed, and from which the frames are discharged through an outlet at the top.

The objective of this invention is to provide a processing device capable of preventing the transport of frames that have warped beyond a threshold, or two frames that have stuck together, to a subsequent process.

According to the present invention, the following processing apparatus is provided that solves the above problems. That is,
A processing apparatus for handling a frame having a central opening for accommodating wafers,
The system includes a frame storage means for stacking and housing multiple frames and having an outlet formed at the top, a frame transport means for holding and transporting frames from the frame storage means, a frame support table for supporting frames transported by the frame transport means, and a control means.
The frame housing means comprises a frame lifting table that supports the lowest frame and raises and lowers the loaded frames, and a frame detection sensor that detects the uppermost frame.
The control means includes a processing device that, when the uppermost frame is unloaded by the frame transport means and the frame directly below it rises and the frame detection sensor detects the frame, determines that the frame unloaded by the frame transport means is abnormal and displays an error if the amount of the frame lifting table rises exceeds a threshold.

Preferably, if an error is displayed, the frame unloaded by the frame transport means is placed on the NG frame table.

The frame detection sensor is preferably composed of a light-emitting element and a light-receiving element arranged to flank the center of the frame.

The apparatus of the present invention is
A processing apparatus for handling a frame having a central opening for housing a wafer,
The system includes a frame storage means for stacking and housing multiple frames and having an outlet formed at the top, a frame transport means for holding and transporting frames from the frame storage means, a frame support table for supporting frames transported by the frame transport means, and a control means.
The frame housing means comprises a frame lifting table that supports the lowest frame and raises and lowers the loaded frames, and a frame detection sensor that detects the uppermost frame.
The control means, when the uppermost frame is unloaded by the frame transport means and the frame directly below it rises and the frame detection sensor detects the frame, determines that the frame unloaded by the frame transport means is abnormal and displays an error if the amount the frame lifting table rises exceeds a threshold, thereby preventing the transport of bent frames or two frames stuck together that exceed the threshold to the next process.

A perspective view of a processing apparatus configured according to the present invention. A side view of the frame housing mechanism shown in Figure 1.

The following describes preferred embodiments of the processing apparatus of the present invention with reference to the drawings.

(Processing device 2)
As shown in Figure 1, the processing device 2 includes a frame storage means 4 on which a plurality of frames F are stacked and housed and which has an outlet formed at the top; a frame transport means 6 that holds and transports the frames F from the frame storage means 4; a frame support table 8 that supports the frames F transported by the frame transport means 6; and a control means 10.

(Frame F)
The frame F handled by the processing apparatus 2 is annular in shape and has a circular opening Fa in the center for accommodating a disc-shaped wafer (not shown). The frame F may be made of a metal material (e.g., stainless steel) or a resin material. The thickness of the frame F is appropriate (e.g., about 1 to 2 mm) depending on the diameter of the wafer to be accommodated in the opening Fa and the material of the frame F.

(Frame housing means 4)
The frame storage means 4 includes a frame lifting table 12 that supports the lowest frame F and raises and lowers the loaded frame F, and a frame detection sensor 14 that detects the uppermost frame F.

(Frame height adjustable table 12)
The frame lifting table 12 is supported so as to be able to move up and down within a housing 16 which has an exit 16a at the top. The housing 16 is equipped with a door 18 with a handle 18a. By grasping the handle 18a and opening the door 18, the frame F can be loaded onto the frame lifting table 12 inside the housing 16 and housed there.

Referring to both Figure 1 and Figure 2, the housing 16 is equipped with a Z-axis guide member 20 (see Figure 1) that guides the raising and lowering of the frame lifting table 12, and a lifting mechanism 22 (see Figure 2) that raises and lowers the frame lifting table 12. Note that the Z-axis guide member 20 is omitted in Figure 2.

As shown in Figure 2, the lifting mechanism 22 includes a ball screw 24 connected to the frame lifting table 12 and extending in the Z-axis direction, and a motor 26 that rotates the ball screw 24. The lifting mechanism 22 converts the rotational motion of the motor 26 into linear motion using the ball screw 24 and transmits it to the frame lifting table 12, thereby raising and lowering the frame lifting table 12 in the Z-axis direction.

The Z-axis direction is the vertical direction indicated by arrow Z in Figure 1. The X-axis direction, indicated by arrow X in Figure 1, is perpendicular to the Z-axis direction, and the Y-axis direction, indicated by arrow Y in Figure 1, is perpendicular to both the X-axis and Z-axis directions. The XY plane defined by the X-axis and Y-axis directions is essentially horizontal.

As shown in Figure 2, the illustrated embodiment is provided with a position detector 28 for detecting the Z-axis position of the frame lifting table 12. The position detector 28 includes a scale 30 fixed to a suitable bracket (not shown) and extending in the Z-axis direction, and a scale reading unit 32 mounted on the frame lifting table 12. If the motor 26 of the lifting means 22 is a pulse motor, the Z-axis position of the frame lifting table 12 can also be detected based on the count value of the drive pulses that drive the pulse motor.

(Frame detection sensor 14)
Referring to Figure 1, the frame detection sensor 14 will be described. The frame detection sensor 14 has a light-emitting element 34 and a light-receiving element 36. The light-emitting element 34 and the light-receiving element 36 are attached to the upper end of the housing 16 and are arranged to sandwich the center of the frame F that is loaded on the frame lifting table 12.

Furthermore, the frame detection sensor 14 is configured such that when the light-receiving element 36 is receiving light emitted by the light-emitting element 34, the uppermost frame F is not in its predetermined position (at the same height as the upper edge of the housing 16). The sensor detects that the uppermost frame F is in its predetermined position when the light-receiving element 36 can no longer receive light emitted by the light-emitting element 34.

(Frame transport means 6)
As shown in Figure 1, the frame transport means 6 includes an X-axis guide member 38 extending in the X-axis direction, an X-axis movable member 40 supported by the X-axis guide member 38 so as to be movable in the X-axis direction, an X-axis feed means (not shown) for moving the X-axis movable member 40 in the X-axis direction, a Z-axis movable member 42 supported by the X-axis movable member 40 so as to be movable in the Z-axis direction, and a Z-axis feed means (not shown) for moving the Z-axis movable member 42 in the Z-axis direction.

The X-axis feed mechanism of the frame transport mechanism 6 may have a configuration comprising a ball screw connected to the X-axis movable member 40 and extending in the X-axis direction, and a motor for rotating this ball screw. The Z-axis feed mechanism may have a configuration comprising a ball screw connected to the Z-axis movable member 42 and extending in the Z-axis direction, and a motor for rotating this ball screw.

The Z-axis movable member 42 of the frame transport means 6 includes a holding portion 44 that holds the frame F. In the illustrated embodiment, the holding portion 44 has a rectangular substrate 46 and a plurality of suction pads 48 provided on the lower surface of the substrate 46. The suction pads 48 are connected to a suction means (not shown).

In the frame transport means 6, the uppermost frame F (the frame F located at the predetermined position) housed in the frame housing means 4 is held by suction using the suction pad 48 of the holding part 44. Then, by moving the X-axis movable member 40 and the Z-axis movable member 42, the uppermost frame F, which has been held by suction, is transported out of the frame housing means 4.

(Frame support table 8)
Continuing the explanation with reference to Figure 1, the frame support table 8 is supported by the Z-axis guide member 50 so as to be able to move up and down. Although not shown in the figure, the Z-axis guide member 50 is equipped with a suitable lifting mechanism (for example, an air drive source or an electric drive source) for raising and lowering the frame support table 8.

The frame support table 8 is raised and lowered by a lifting mechanism between a lower position (shown by a solid line in Figure 1) where it receives the frame F transported by the frame transport means 6, and an upper position (shown by a dashed line in Figure 1) where dicing tape can be attached to the frame F on the frame support table 8 by a tape attachment means (not shown).

(Control means 10)
The control means 10 consists of a computer having a processor and memory, and the memory of the control means 10 stores a threshold value corresponding to the thickness of the frame F (a value slightly larger than the thickness of the frame F) for each type of frame F.

The control means 10 controls the operation of the processing unit 2. Specifically, it controls the operation of the lifting mechanism 22 of the frame lifting table 12, the suction mechanism of the frame transporting mechanism 6, the X and Z axis feeding mechanism, and the lifting mechanism of the frame support table 8. Information acquired by the frame detection sensor 14 and the position detector 28 is also transmitted to the control means 10.

Furthermore, a monitor 52 is electrically connected to the control means 10. The monitor 52 displays screens corresponding to commands from the control means 10 (for example, an operation screen for operating the processing unit 2, and an error screen for notifying the operator of errors when errors occur in the processing unit 2).

(NG Frame Table 54)
As shown in Figure 1, an NG frame table 54 is provided between the frame housing means 4 and the frame support table 8. When the control means 10 determines that a frame F that has been unloaded by the frame transport means 6 is abnormal, the frame F that has been determined to be abnormal is placed on the NG frame table 54.

(Operation of processing unit 2)
The operation of the processing unit 2 (control of the control means 10) as described above will now be explained.

Before operating the processing unit 2, multiple identical frames F are loaded and stored on the frame lifting table 12 of the frame storage means 4, and the types of frames F stored are input to the control means 10. The control means 10 then selects the frame F and its thickness to be compared from the stored frame F.

When the operator instructs the processing unit 2 to start operation, the control unit 10 raises the frame lifting table 12 using the lifting unit 22 until the uppermost frame F is detected by the frame detection sensor 14. Once the uppermost frame F is detected, the frame lifting table 12 is stopped.

Next, the Z-axis position (vertical position) of the frame lifting table 12 is detected by the position detector 28. In the illustrated embodiment, at the stopping position of the frame lifting table 12, the scale reading unit 32 reads the value of the scale 30, and the read value is stored as the first value.

After storing the first value, the control means 10 moves the X-axis movable member 40 of the frame transport means 6 to position the holding unit 44 above the frame housing means 4. Then, it lowers the holding unit 44, bringing the suction pad 48 of the holding unit 44 into contact with the upper surface of the uppermost frame F housed in the frame housing means 4. Next, the suction means generates suction force on the suction pad 48, holding the uppermost frame F with the suction pad 48. Finally, the holding unit 44 is raised, and the frame F, held by the suction pad 48, is removed from the frame housing means 4.

Once frame F is removed, the control means 10 raises the frame lifting table 12 until the uppermost frame F is detected by the frame detection sensor 14. Then, when the uppermost frame F within the frame storage means 4 (the frame F directly below the frame F removed by the frame transport means 6) is detected, the frame lifting table 12 is stopped.

After stopping the frame lifting table 12, the position of the frame lifting table 12 in the Z-axis direction is detected by the position detector 28. In the illustrated embodiment, at the stopping position of the frame lifting table 12, the scale reading unit 32 reads the value of the scale 30, and the read value is stored as a second value.

After storing the second value, the difference between the first and second values is calculated. The calculated difference represents the amount the frame lifting table 12 rises, corresponding to the thickness of the frame F that was immediately removed by the frame transporting means 6.

The control means 10 then determines that the removed frame F is appropriate if the amount the frame lifting table 12 rises (the thickness of the frame F removed immediately before) is below a pre-stored threshold. In this case, the removed frame F is transported to the frame support table 8. Once the frame F is transported to the frame support table 8, dicing tape is applied to it by a tape application means (not shown).

On the other hand, if the lifting amount of the frame lifting table 12 exceeds a threshold, the control means 10 determines that the unloaded frame F is abnormal and displays an error to notify the operator of the abnormal frame F. The error may be displayed, for example, on the monitor 52, or by lighting or flashing a lamp, or by generating a warning sound. Furthermore, if an error is displayed, the unloaded frame F is not transported to the frame support table 8, but placed on the NG frame table 54.

As described above, in the illustrated embodiment of the processing apparatus 2, the operator is notified of the presence of an abnormal frame F by displaying an error message. This prevents the transport of frames F that have warped beyond a threshold, or two frames F stuck together by residual adhesive, to subsequent processes.

2: Processing device F: Frame Fa: Frame opening 4: Frame housing means 6: Frame transport means 8: Frame support table 10: Control means 12: Frame lifting table 14: Frame detection sensor 34: Light-emitting element 36: Light-receiving element 54: NG frame table

Claims (3)

A processing apparatus for handling a frame having a central opening for housing a wafer,
The system includes a frame storage means for stacking and housing multiple frames and having an outlet formed at the top, a frame transport means for holding and transporting frames from the frame storage means, a frame support table for supporting frames transported by the frame transport means, and a control means.
The frame housing means comprises a frame lifting table that supports the lowest frame and raises and lowers the loaded frames, and a frame detection sensor that detects the uppermost frame.
The control means is a processing device that, when the uppermost frame is unloaded by the frame transport means and the frame directly below it rises and the frame detection sensor detects the frame, determines that the frame unloaded by the frame transport means is abnormal and displays an error if the amount of the frame lifting table rises exceeds a threshold. The processing apparatus according to claim 1, wherein, if an error is displayed, the frame unloaded by the frame transport means is placed on the NG frame table. The processing apparatus according to claim 1, wherein the frame detection sensor is a light-emitting element and a light-receiving element arranged to sandwich the center of the frame.