JP7436165B2 - Dicing unit diagnostic method and dicing system - Google Patents

Description

The present invention relates to a dicing unit diagnostic method and a dicing system.

Conventionally, when dicing a plate-shaped semiconductor wafer into individual pieces, chips on the edge of the chip caused by dicing would damage the device if it reached the device, so processing was temporarily stopped during processing of the workpiece. It is known to perform a so-called kerf check in which a cut groove (kerf) is imaged and the size of chipping that occurs is measured.

If the size of chipping detected during the kerf check exceeds a preset tolerance, the device issues a warning so that the operator can take appropriate action. Thereby, it is possible to prevent processing from continuing in a state where the chipping size exceeds an allowable value and from continuing to produce defective devices.

Patent Document 1 discloses a technology that automatically determines the usage limit of a cutting blade by forming a processing groove on the edge of a wafer and performing image analysis of the processing groove, and the cutting blade can be replaced in a timely manner by automatic judgment. This will prevent the production of defective devices.

Japanese Patent Application Publication No. 2015-85398

On the other hand, it is known that when the wafer is divided and the chip side surface, that is, the surface of the dividing surface is rough, the strength of the chip is poor. However, in the past, the surface roughness of the side surfaces of chips had not been confirmed.

For this reason, if the workpiece continues to be machined even though the dividing surface of the chip is rough, a chip with low strength is formed, which in turn leads to the production of defective devices. There was a risk that it would continue.

An object of the present invention is to provide a method for diagnosing a dicing unit that can prevent the formation of chips with low strength and further prevent the continued production of defective devices.

According to one aspect of the invention,
A method for diagnosing a dicing unit that dices a workpiece held on a holding table, the method comprising:
a holding step of holding the workpiece on the holding table;
a dicing step in which the workpiece held in the holding step is diced into pieces by the dicing unit;
a detection step of detecting the roughness of the dividing surface of the workpiece divided in the dicing step;
After performing the detection step, an abnormality determination step of determining that the dicing unit is abnormal when the roughness of the divided surface is outside a predetermined tolerance range;
A method for diagnosing a dicing unit including:

Further, a dicing unit that dices the workpiece held by the holding table;
a detection unit that detects the roughness of the dividing surface of the workpiece cut into pieces by the dicing unit;
a controller that controls the detection unit;
A dicing system comprising:
The controller is
The roughness of the divided surface detected by the detection unit is compared with a preset roughness tolerance range, and when the roughness is outside the predetermined tolerance range, the dicing unit is determined to be abnormal. The dicing system includes an abnormality determination section.

According to the present invention, the roughness of the dividing surface (cutting surface) of the singulated workpiece is detected, and the dicing unit is determined to be abnormal when the roughness of the dividing surface is outside a predetermined tolerance range. , processing can be stopped when an abnormality is determined, and it is possible to prevent continued production of defective devices.

FIG. 1 is a perspective view showing a dicing system in which a dicing unit and an inspection unit are configured in-line. FIG. 2 is a perspective view showing the inspection unit with some of its components omitted. It is a perspective view showing a wafer unit. FIG. 4(A) is a sectional view showing a wafer unit placed on the pushing up mechanism, and FIG. 4(B) is a sectional view showing a part of the pushing up mechanism in an enlarged manner. It is a perspective view showing a pickup mechanism. FIG. 6(A) is a cross-sectional view showing the wafer unit in a state where the tape is sucked by the push-up mechanism, and FIG. 6(B) is a cross-sectional view showing the wafer unit in a state where the chip is pushed up by the push-up mechanism. FIG. 6(C) is a cross-sectional view showing the wafer unit with chips picked up by the collet. FIG. 7(A) is a diagram illustrating a configuration for rotating the chip support base. FIG. 7(B) is a diagram illustrating a configuration for rotating the collet of the pickup mechanism. FIG. 2 is a functional block diagram illustrating an example of a device configuration for determining an abnormality. 2 is a flowchart illustrating an example of abnormality determination.

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view showing a dicing system 301 in which a dicing unit 302 (cutting device) and an inspection unit 2 are configured in-line. FIG. 2 is a perspective view showing the configuration of the inspection unit 2. As shown in FIG.

First, the configuration of a wafer or the like as a workpiece to be inspected in the present invention will be explained using FIG. 3.
FIG. 3 is a perspective view showing the wafer unit 11 in which the wafer 13 is attached to the tape 19, and shows the state after being processed by the dicing unit 302 (FIG. 1). The wafer 13 is formed into a disk shape using a material such as silicon, and includes a front surface 13a and a back surface 13b. On the front surface 13a side of the wafer 13, a plurality of devices 15 including ICs (Integrated Circuits), LSIs (Large Scale Integrations), LEDs (Light Emitting Diodes), etc. are formed.

Further, the wafer 13 has been cut along a plurality of dividing lines (streets) 17 arranged in a grid pattern so as to intersect with each other. Each of the plurality of devices 15 is formed on the surface 13a side of each region partitioned by the planned dividing line 17.

Note that there are no restrictions on the material, shape, structure, size, etc. of the wafer 13. For example, the wafer 13 may be a substrate made of a material other than silicon, such as a semiconductor (SiC, GaAs, InP, GaN, etc.), sapphire, glass, ceramics, resin, metal, or the like. Furthermore, there are no restrictions on the type, quantity, shape, structure, size, arrangement, etc. of the device 15.

A circular tape 19 is attached to the back surface 13b of the wafer 13. For example, the tape 19 is composed of a flexible film in which a rubber-based or acrylic-based adhesive layer (glue layer) is formed on a base material made of a resin such as polyolefin, polyvinyl chloride, or polyethylene terephthalate. Note that the diameter of the tape 19 is larger than the diameter of the wafer 13, and the wafer 13 is attached to the center of the tape 19.

Furthermore, an annular frame 21 made of metal or the like and having a circular opening 21a in the center is attached to the outer circumference of the tape 19. Thereby, the wafer 13 is supported by the annular frame 21 via the tape 19 while being placed inside the opening 21a.

The wafer 13 is cut along a planned dividing line 17 and divided into a plurality of chips 23 each including a device 15. For example, a dicing unit 302 (FIG. 1), which will be described later, is used to divide the wafer 13. The wafer 13 is cut and divided into a plurality of chips 23 by rotating the cutting blade and cutting into the wafer 13 along the planned dividing line 17 . Note that there are no restrictions on the method of dividing the wafer.

Each of the plurality of chips 23 is peeled off from the tape 19 in a later step. Therefore, it is preferable that the tape 19 has a property that its adhesive strength is reduced by performing a predetermined treatment. As the tape 19, for example, an ultraviolet curable tape that is cured by irradiation with ultraviolet rays can be used. Further, as the tape 19, a tape whose adhesive layer contains microcapsules that expand when exposed to ultraviolet rays, a foaming agent that expands when exposed to ultraviolet rays, or the like may be used. When such tape 19 is irradiated with ultraviolet rays, the adhesive strength of tape 19 to chip 23 is reduced.

As described above, the plurality of chips 23 divided on the wafer unit 11 are picked up by the pickup mechanism 70 (FIG. 2), which will be described later.

As shown in FIG. 1, the dicing unit 302 dices the wafer 13 (FIG. 3), which is a workpiece. The dicing unit 302 includes a base 304 that supports each component.

A cassette support base 306 is provided at the front corner of the base 304 and is raised and lowered by a lift mechanism (not shown). A cassette 308 that accommodates a plurality of wafers 13 (FIG. 3) is placed on the upper surface of the cassette support stand 306.

An opening 304b that is long in the X-axis direction (left-right direction, processing feed direction) is formed on the side of the cassette support base 306. A moving table 316 including a holding table 318 and a ball screw type X-axis moving mechanism (not shown) for moving the moving table 316 in the It is configured to be moved in the axial direction (processing feed). The opening portion of the opening 304b is covered by a movable table 316 and a bellows-type table cover 312.

The holding table 318 is for suctioning and holding the wafer 13 (FIG. 3), and is provided with its holding surface exposed on the upper side. This holding table 318 is connected to a rotation drive source (not shown) such as a motor, and rotates about the Z-axis (vertical axis) as a rotation axis.

The upper surface of the holding table 318 is a holding surface 318a that sucks and holds the wafer 13 (FIG. 3) from below. The holding surface 318a is formed approximately parallel to the X-axis direction and the Y-axis direction (back-and-forth direction, indexing feed direction), and is connected to the ejector via a suction path (not shown) provided inside the holding table 318. connected to a suction source such as

Four clamps 320 are provided around the holding table 318 for fixing the annular frame 21 (FIG. 3) that supports the wafer 13 (FIG. 3) from all sides.

A transport unit (not shown) that transports the wafer 13 (FIG. 3) described above to the holding table 318 or the like is arranged in a region adjacent to the opening 304b. The wafer 13 (FIG. 3) carried out from the cassette 308 by the transfer unit is placed on the holding table 318, for example, with the front side exposed upward.

A gate-shaped column 326 for supporting two sets of cutting units 324 is arranged on the upper surface of the base 304 so as to straddle the opening 304b. Two sets of cutting unit moving mechanisms 328 are provided at the upper front surface of the column 326 to move each cutting unit 324 in the Y-axis direction and the Z-axis direction.

The Y-axis moving plate 332 of each cutting unit moving mechanism 328 is slidably attached to a pair of long Y-axis guide rails 330 provided in parallel to the Y-axis direction on the front surface of the column 326. The unit moving mechanism 328 as a whole is configured to be movable in the Y-axis direction.

A nut portion (not shown) is provided on the back side (rear side) of each Y-axis moving plate 332, and a Y-axis ball screw 334 that is approximately parallel to the Y-axis guide rail 330 is mounted on this nut portion. They are each screwed together. A Y-axis pulse motor 336 is connected to one end of each Y-axis ball screw 334 . When the Y-axis ball screw 334 is rotated by the Y-axis pulse motor 336, the Y-axis moving plate 332 moves in the Y-axis direction along the Y-axis guide rail 330.

A pair of Z-axis guide rails 338 that are long in the Z-axis direction are provided on the surface (front surface) of each Y-axis moving plate 332. That is, the Z-axis guide rail 338 is arranged so that its longitudinal direction is parallel to the Z-axis direction. Further, a Z-axis moving plate 340 is slidably attached to the Z-axis guide rail 338.

A nut portion (not shown) is provided on the back side (rear side) of each Z-axis moving plate 340, and a Z-axis ball screw 342 that is generally parallel to the Z-axis guide rail 338 is mounted in this nut portion. They are each screwed together. A Z-axis pulse motor 344 is connected to one end of each Z-axis ball screw 342 . When the Z-axis ball screw 342 is rotated by the Z-axis pulse motor 344, the Z-axis moving plate 340 moves in the Z-axis direction along the Z-axis guide rail 338.

A cutting unit 324 is provided at the bottom of each Z-axis moving plate 340. A camera 333 (imaging unit) is provided at a position adjacent to one of the cutting units 324 to take an image of the wafer etc. sucked and held by the holding table 318.

When each cutting unit moving mechanism 328 moves the Y-axis moving plate 332 in the Y-axis direction, the cutting unit 324, camera, and laser displacement meter move in the Y-axis direction (indexing feed). Moreover, if each cutting unit moving mechanism 328 moves the Z-axis moving plate 340 in the Z-axis direction, the cutting unit 324 and camera 333 move in the Z-axis direction (cut feed).

An opening 304c is formed at a position opposite to the cassette support base 306 across the opening 304b. A cleaning unit 350 for cleaning the wafer and the like after being cut (cut) by the cutting unit 324 is disposed within the opening 304c.

In addition, components such as an elevating mechanism for elevating and lowering the cassette support base 306, an X-axis moving mechanism, a holding table 318, a transport unit, a cutting unit 324, a cutting unit moving mechanism 328, a camera 333, and a cleaning unit 350 are controlled by controls not shown. connected to and controlled by the unit.

Each of the above-mentioned components is covered by an exterior cover (not shown) that forms the appearance of the dicing unit 302. A touch panel type monitor 352 serving as a user interface is provided on the outside of this cover (not shown), and the monitor 352 is connected to the control unit described above.

The dicing unit 302 is configured as a cutting device including a cutting unit 324, and also includes a laser oscillator and a condensing lens that focuses and irradiates the workpiece with a laser beam emitted from the laser oscillator. It may be configured in a laser processing device that performs laser dicing on a workpiece.

Next, the inspection unit 2 shown in FIGS. 1 and 2 will be explained.
The inspection unit 2 includes a base 4 that supports each component that constitutes the inspection unit 2. A temporary storage table 4a is provided at one end of the front side of the base 4 (upper right side in FIGS. 1 and 2), and is cleaned by the cleaning unit 350 of the dicing unit 302 by the delivery and conveyance device 5 (FIG. 1). The wafer unit 11 (FIG. 3) that has been finished is transported to the temporary storage table 4a.

The delivery and conveyance device 5 shown in FIG. 1 is configured to be movable in the X-axis direction and the Y-axis direction, and holds the annular frame of the wafer unit 11 (FIG. 3) with a holding section provided at the lower end, and cleans the wafer unit 11 (FIG. 3). This allows the wafer unit to be transferred from the unit 350 to the temporary storage table 4a.

A temporary storage mechanism 10 that can temporarily store wafer units in two stages is provided on the front side of the temporary storage table 4a shown in FIG. 1 (lower left side in FIGS. 1 and 2). The temporary storage mechanism 10 includes a pair of guide rails 12 arranged parallel to each other. Each of the pair of guide rails 12 is configured to form a two-tiered shelf, with a first parallel to the X-axis direction (first horizontal direction, left-right direction) and a first parallel to the Y-axis direction (second horizontal direction, front-back direction). It includes a support surface 12a and a second support surface 12b.

As shown in FIG. 1, each of the first support surfaces 12a is arranged above the second support surface 12b so as to overlap with the second support surface 12b. The pair of first support surfaces 12a and the pair of second support surfaces 12b each support the lower surface side of the end portion (annular frame 21 (FIG. 3)) of the wafer unit. For example, a pair of first support surfaces 12a support a wafer unit transferred from a temporary storage table 4a, and a pair of second support surfaces 12b support a wafer unit transferred from a frame fixing mechanism 14, which will be described later.

As shown in FIG. 1, a frame fixing mechanism 14 for fixing the annular frame 21 (FIG. 3) of the wafer unit is provided behind the temporary storage mechanism 10. The frame fixing mechanism 14 includes a frame support part 16 that supports the bottom side of the annular frame (FIG. 3), and a frame presser part 18 that is arranged above the frame support part 16 and contacts the top side of the annular frame 21 (FIG. 3). Equipped with. The frame supporting part 16 and the frame pressing part 18 are each formed into an annular shape corresponding to the shape of the annular frame (FIG. 3), and are arranged so as to overlap each other.

The frame support section 16 shown in FIG. 1 is configured to be movable along the Z-axis direction (vertical direction, up and down direction). When the frame support 16 is moved upward with the wafer unit arranged so that the annular frame 21 (FIG. 3) is supported by the frame support 16, the annular frame (FIG. 3) is moved between the frame support 16 and the frame. It is sandwiched and fixed by the holding part 18.

Note that whether or not the annular frame 21 (FIG. 3) is properly fixed by the frame fixing mechanism 14 is determined by, for example, whether the frame support part 16 and the frame pressing part 18 are electrically connected through the annular frame (FIG. 3). This is confirmed by detecting whether the

Further, as shown in FIG. 1, above the temporary storage mechanism 10 and the frame support section 16, there is a transport mechanism (transport means) for transporting the wafer unit 11 (FIG. 3) between the temporary storage table 4a and the frame fixing mechanism 14. )20 are provided. The transport mechanism 20 is configured to be movable along the Y-axis direction and the Z-axis direction, and includes a first gripping part 22a and a second gripping part 22b that grip the annular frame 21 (FIG. 3) of the wafer unit 11 from above and below. Equipped with. Note that the first gripping part 22a is provided on the temporary storage table 4a side of the transport mechanism 20, and the second gripping part 22b is provided on the frame fixing mechanism 14 side of the transport mechanism 20.

As shown in FIG. 1, when carrying out the wafer unit 11 (FIG. 3) from the temporary storage table 4a, the end of the wafer unit 11 (FIG. 3) accommodated in the temporary storage table 4a is gripped by the first gripping part 22a. In this state, the transport mechanism 20 is moved toward the temporary storage mechanism 10 along the Y-axis direction. As a result, the wafer unit 11 (FIG. 3) is pulled out from the temporary storage table 4a and placed on the pair of first support surfaces 12a (upper stage) of the temporary storage mechanism 10. After that, the grip by the first grip part 22a is released.

Next, while the end of the wafer unit 11 (FIG. 3) on the temporary storage table 4a side is gripped by the second gripping part 22b of the transport mechanism 20, the transport mechanism 20 is moved toward the frame fixing mechanism 14 along the Y-axis direction. move it. As a result, the wafer unit 11 (FIG. 3) is transferred between the frame support section 16 and the frame pressing section 18, and the annular frame 21 (FIG. 3) is supported by the frame support section 16.

As shown in FIGS. 1 and 2, a notch 18a formed by cutting out the frame pressing part 18 is provided on the temporary placement mechanism 10 side of the frame pressing part 18. This notch 18a is configured to have a size that allows the transport mechanism 20 to pass through. Thereby, when the wafer unit 11 (FIG. 3) is transported to the frame fixing mechanism 14, the transport mechanism 20 can be prevented from coming into contact with the frame holding part 18.

Thereafter, as shown in FIG. 1, the grip by the second grip part 22b is released, and the frame support part 16 is moved upward. As a result, the annular frame 21 (FIG. 3) is sandwiched and fixed between the frame support part 16 and the frame presser part 18.

As shown in FIGS. 1 and 2, the frame fixing mechanism 14 is supported by a positioning mechanism 30 that controls the position of the frame fixing mechanism 14. As shown in FIGS. The positioning mechanism 30 includes an X-axis moving mechanism 32 that moves the frame fixing mechanism 14 along the X-axis direction, and a Y-axis moving mechanism 42 that moves the frame fixing mechanism 14 along the Y-axis direction. The horizontal position of the frame fixing mechanism 14 is controlled by the X-axis moving mechanism 32 and the Y-axis moving mechanism 42.

The X-axis moving mechanism 32 includes a pair of guide rails 34 arranged on the base 4 along the X-axis direction. A ball screw 36 is provided between the pair of guide rails 34 and is arranged generally parallel to the pair of guide rails 34 . Furthermore, a pulse motor 38 that rotates the ball screw 36 is connected to one end of the ball screw 36 .

A moving block 40 is slidably arranged on the pair of guide rails 34. A nut portion (not shown) is provided on the lower surface side (back side) of the moving block 40, and this nut portion is screwed onto the ball screw 36. When the ball screw 36 is rotated by the pulse motor 38, the moving block 40 moves in the X-axis direction along the pair of guide rails 34.

The Y-axis moving mechanism 42 includes a pair of guide rails 44 arranged on the moving block 40 along the Y-axis direction. A ball screw 46 is provided between the pair of guide rails 44 and is arranged generally parallel to the pair of guide rails 44 . Furthermore, a pulse motor 48 that rotates the ball screw 46 is connected to one end of the ball screw 46 .

As shown in FIG. 1, the frame fixing mechanism 14 is slidably disposed on the pair of guide rails 44. As shown in FIG. A nut portion (not shown) is provided on the support portion 14f of the frame fixing mechanism 14, and this nut portion is screwed onto the ball screw 46. When the ball screw 46 is rotated by the pulse motor 48, the frame fixing mechanism 14 moves in the Y-axis direction along the pair of guide rails 44.

As shown in FIGS. 1 and 2, the moving block 40 is configured in a plate shape, and has an opening 41 that penetrates in the vertical direction at a position below the frame fixing mechanism 14. Through this opening 41, it becomes possible to push up from below by a pushing up mechanism 50, which will be described later.

A rectangular opening 4b is provided in a region of the base 4 sandwiched between the pair of guide rails 36. Inside the opening 4b, a cylindrical push-up mechanism (push-up means) 50 is provided that pushes up the chips 23 (FIG. 3) included in the wafer 13 of the wafer unit 11 upward from the lower surface side. The thrusting mechanism 50 is connected to an elevating mechanism (not shown) composed of an air cylinder or the like, and moves up and down along the Z-axis direction.

When the annular frame 21 of the wafer unit 11 (FIG. 3) is fixed by the frame fixing mechanism 14 and the frame fixing mechanism 14 is moved along the X-axis direction by the positioning mechanism 30, the wafer unit 11 is positioned above the opening 4b. It will be done. Then, a predetermined chip 23 (FIG. 3) included in the wafer 13 is pushed upward by the pushing up mechanism 50.

FIG. 4(A) is a cross-sectional view showing the wafer unit 11 arranged above the push-up mechanism 50. The push-up mechanism 50 includes an outer layer portion 52 formed in a hollow cylindrical shape, and a square column-shaped push-up portion 54 arranged inside the outer layer portion 52.

FIG. 4(B) is an enlarged cross-sectional view of a part of the push-up mechanism 50. A plurality of suction grooves 52b are formed concentrically along the circumferential direction of the outer layer portion 52 on the upper surface 52a side of the outer layer portion 52. The suction grooves 52b are each connected to a suction source 58, such as an ejector, through a suction path (not shown) formed inside the push-up mechanism 50 and a valve 56 (FIG. 4(A)).

The push-up portion 54 also includes a first push-up pin 54a formed in the shape of a square column, a second push-up pin 54b formed in the shape of a hollow square column and surrounding the first push-up pin 54a, and a second push-up pin 54b formed in the shape of a hollow square column. The third push-up pin 54c surrounds the second push-up pin 54b, and the fourth push-up pin 54d is formed into a hollow square column shape and surrounds the third push-up pin 54c. The first push-up pin 54a, the second push-up pin 54b, the third push-up pin 54c, and the fourth push-up pin 54d are each connected to a lifting mechanism (not shown) composed of a motor, etc., and are moved along the Z-axis direction. Go up and down.

When the push-up mechanism 50 is raised with the wafer unit 11 positioned above the push-up mechanism 50, the chips 23 disposed at a position overlapping with the push-up mechanism 50 are pushed up. Note that the dimensions of the push-up mechanism 50 are adjusted as appropriate depending on the size of the chip 23.

The chip 23 and the push-up mechanism 50 are aligned by adjusting the position of the frame fixing mechanism 14 using the positioning mechanism 30 (see FIGS. 1 and 2). A wafer imaging camera 60 (see FIGS. 1 and 2) placed above the push-up mechanism 50 is used for this alignment.

The wafer imaging camera 60 is placed at a position where it can image the entire wafer 13 (see FIG. 3) placed above the opening 4b. Based on the image of the wafer 13 captured by the wafer imaging camera 60, the position of the frame fixing mechanism 14 is adjusted so that a predetermined chip 23 overlaps the push-up mechanism 50.

Note that it is preferable to provide a light that irradiates light toward the wafer 13 near the push-up mechanism 50. When photographing the wafer 13 with the wafer imaging camera 60, a clear image can be obtained by irradiating the wafer 13 with light. Note that there is no restriction on the position where the light is provided. For example, the light is provided at the bottom of the opening 4b adjacent to the push-up mechanism 50. Further, the push-up mechanism 50 may be formed of a transparent member, and a light may be provided inside the push-up mechanism 50.

As shown in FIG. 2, the chip 23 pushed up by the pushing up mechanism 50 is picked up by the pickup mechanism 70. The pick-up mechanism 70 includes a collet 76 that picks up the chip 23 pushed up by the push-up mechanism 50, and is connected to a collet moving mechanism (collet moving means) 80 that controls the position of the collet 76.

FIG. 5 is a perspective view showing the pickup mechanism 70. The pickup mechanism 70 includes a movable base 72 connected to the collet moving mechanism 80, and is arranged along the X-axis direction from the movable base 72 toward the side opposite to the collet moving mechanism 80. It includes a columnar arm 74 that connects to the mechanism 80. The arm 74 includes a columnar first support part 74a connected to the collet movement mechanism 80 via the movable base 72, and a second support part 74b protruding downward from the tip of the first support part 74a. Be prepared.

Note that the first support portion 74a and the second support portion 74b are configured to be able to be coupled and separated from each other. For example, the first support portion 74a and the second support portion 74b are configured to be detachable from each other using a tool changer or the like. Further, the first support portion 74a is configured to move in the X-axis direction by an X-axis direction movement mechanism 74c, and thereby the second support portion 74b is configured to be movable in the X-axis direction. Thereby, when storing the chip in the chip tray 501 described later, the storing position in the X-axis direction can be selected.

As shown in FIG. 5, a collet 76 that holds the chip 23 (FIG. 3) is fixed to the lower end side of the second support portion 74b. The lower surface of the collet 76 constitutes a suction surface 76a that suctions and holds the chip 23. The suction surface 76a is connected to a suction source (not shown) via a suction path (not shown) formed inside the collet 76. With the chip 23 in contact with the suction surface 76a of the collet 76, by applying negative pressure from a suction source to the suction surface 76a, the chip 23 is suction-held by the collet 76.

As shown in FIG. 2, the pickup mechanism 70 is connected to a collet moving mechanism 80. The collet moving mechanism 80 includes a Y-axis moving mechanism 82 that moves the pickup mechanism 70 along the Y-axis direction, and a Z-axis moving mechanism 92 that moves the pickup mechanism 70 along the Z-axis direction. The Y-axis moving mechanism 82 and the Z-axis moving mechanism 92 control the position of the collet 76 in the Y-axis direction and the Z-axis direction.

The Y-axis moving mechanism 82 includes a pair of guide rails 84 arranged along the Y-axis direction. A ball screw 86 is provided between the pair of guide rails 84 and is arranged generally parallel to the pair of guide rails 84 . Furthermore, a pulse motor 88 that rotates the ball screw 86 is connected to one end of the ball screw 86 .

A moving block 90 is slidably mounted on the pair of guide rails 84. Further, the moving block 90 is provided with a nut portion (not shown), and this nut portion is screwed onto the ball screw 86. When the ball screw 86 is rotated by the pulse motor 88, the moving block 90 moves in the Y-axis direction along the pair of guide rails 84.

As shown in FIGS. 2 and 5, the Z-axis moving mechanism 92 includes a pair of guide rails 94 arranged along the Z-axis direction on the side surface of the moving block 90. A ball screw 96 is provided between the pair of guide rails 94 and is arranged generally parallel to the pair of guide rails 94 . Furthermore, a pulse motor 98 that rotates the ball screw 96 is connected to one end of the ball screw 96 .

As shown in FIG. 5, a movable base 72 of the pickup mechanism 70 is slidably mounted on the pair of guide rails 94. Further, the movable base 72 is provided with a nut portion (not shown), and this nut portion is screwed onto a ball screw 96. When the ball screw 96 is rotated by the pulse motor 98, the movable base 72 moves in the Z-axis direction along the pair of guide rails 94.

The pick-up mechanism 70 configured as described above picks up the chip 23 (FIG. 3) pushed up by the push-up mechanism 50. An example of the operation of the push-up mechanism 50 and the collet 76 when picking up a predetermined chip 23 from the wafer 13 will be described below.

As shown in FIG. 4A, first, the wafer unit 11 fixed by the frame fixing mechanism 14 is moved by the positioning mechanism 30 and placed above the push-up mechanism 50. Next, based on the image acquired by the wafer imaging camera 60, the position of the frame fixing mechanism 14 is adjusted so that the predetermined chip 23 to be picked up and the push-up mechanism 50 overlap. Note that at this time, the collet 76 of the pickup mechanism 70 is arranged at a position facing (overlapping) the upper surface 50a of the thrusting mechanism 50 (see FIG. 6(A)).

Next, as shown in FIG. 6A, the push-up mechanism 50 is moved upward to bring the upper surface 50a of the push-up mechanism 50 into contact with the tape 19 attached to the back side of the chip 23. In this state, the valve 56 is opened, and the negative pressure of the suction source 58 is applied to the upper surface 52a of the outer layer portion 52 via the suction groove 52b (see FIG. 4(B)). As a result, the area of the tape 19 in contact with the push-up mechanism 50 is attracted. FIG. 6A is a cross-sectional view showing the wafer unit 11 in a state where the tape 19 is sucked by the push-up mechanism 50.

Next, as shown in FIG. 6(B), the push-up portion 54 of the push-up mechanism 50 is moved upward, and the lower surface side of the chip 23 is pushed upward via the tape 19. At this time, each of the first push-up pin 54a, second push-up pin 54b, third push-up pin 54c, and fourth push-up pin 54d (see FIG. 4(B)) that constitute the push-up portion 54 has its upper end at the center of the push-up mechanism 50. The closer it is to the position, the higher the position is. The chip 23 pushed up by the pushing up mechanism 50 is placed above the other chips 23.

Next, as shown in FIG. 6(C), the pickup mechanism 70 is moved downward, and the suction surface 76a of the collet 76, which is arranged to overlap with the chip 23 that has been pushed up, Make contact with the upper surface side of 23. Then, with the suction surface 76a of the collet 76 and the chip 23 in contact with each other, negative pressure is applied to the suction surface 76a. As a result, the chip 23 is sucked and held by the collet 76. When the pickup mechanism 70 is moved upward in this state, the chip 23 is peeled off from the tape 19 and picked up by the collet 76.

Note that if the tape 19 has a property that its adhesive strength is reduced by irradiation with ultraviolet rays, a light source for irradiating ultraviolet rays may be provided on the upper surface 50a side (FIG. 4) of the push-up mechanism 50. In this case, when the push-up mechanism 50 is brought into contact with the tape 19 (see FIG. 6A), ultraviolet rays are irradiated only to the region of the tape 19 located below the chip 23 to be picked up, and the tape 19 is bonded. Power can be partially weakened. This makes it easy to pick up a predetermined chip 23, and the arrangement of other chips 23 is maintained by the adhesive strength of the area of the tape 19 that is not irradiated with ultraviolet rays.

Further, a load cell for measuring the load applied to the chip 23 may be provided on the upper surface 50a side of the push-up mechanism 50 or on the suction surface 76a side of the collet 76. In this case, the load applied to the chip 23 when picking up the chip 23 can be measured by a load cell. Based on the load measured by the load cell, for example, it is checked whether or not the chip 23 is damaged during pickup, and the pickup conditions (such as the height of the collet 76 when picking up the chip 23) are appropriately changed. It becomes possible to do.

Note that the wafer unit 11 after the chips 23 have been picked up may be accommodated in the temporary storage stand 4a again. In this case, first, the frame fixing mechanism 14 is moved to the rear of the temporary storage mechanism 10, and the fixation of the annular frame 21 by the frame fixing mechanism 14 is released.

Thereafter, the end portion of the wafer unit 11 is gripped by the second gripping portion 22b (see FIG. 1) of the transport mechanism 20, and the wafer unit 11 is transported onto the pair of second support surfaces 12b provided in the temporary placement mechanism 10. Then, the end portion of the wafer unit 11 is gripped by the first gripping portion 22a of the transport mechanism 20, and the wafer unit 11 is housed in the temporary storage table 4a.

The chips 23 picked up by the collet 76 are transported forward by the collet moving mechanism 80. As shown in FIG. 1, in front of the push-up mechanism 50, there is a detection mechanism 100 for observing the divided surface (cut surface) of the chip 23 picked up by the collet 76 and detecting the roughness of the divided surface. It is provided.

As shown in FIGS. 2 and 7A, the detection mechanism 100 includes a detection unit 116 that detects the roughness of the divided surface of the chip 23 and a chip support 114.

As shown in FIG. 7A, the chip 23 picked up by the collet 76 is conveyed to the upper surface of the support surface 114a of the chip support stand 114.

As shown in FIG. 7A, the detection unit 116 detects the roughness of the divided surface of the chip 23 placed on the support surface 114a of the chip support stand 114, and uses a confocal microscope or a white interferometer to can be adopted. The detection unit 116 is configured to detect the roughness of the divided surface by moving the chip 23 closer to or away from the chip 23 at a predetermined pitch during detection. The distance to the chip 23 can be changed by moving the entire detection unit 116 using a moving means (not shown) or by moving a detection section provided inside the detection unit 116.

As shown in FIG. 7(A), the chip support stand 114 is configured to be rotatable around the axial direction R. For example, by rotating at 90 degree intervals, each divided surface of the chip 23 is connected to the detection unit. 116. As shown in FIG. 2, the base 4 of the inspection unit 2 is provided with a chip support 114 in an area that overlaps with the moving path of the collet 76. It can be placed in

Then, as shown in FIG. 7A, the detection unit 116 detects the roughness of the first divided surface of the chip 23 supported by the chip support stand 114. The first dividing surface of the chip 23 observed here is one dividing surface 23a among the four dividing surfaces, and this dividing surface 23a faces the detection unit 116, so that the first dividing surface The roughness of 23a is detected. Note that if the dividing surface 23a is tilted and it is difficult to focus the detection unit 116, correction may be made by adjusting the angle of the chip support 114.

Thereafter, the other dividing surfaces 23b and 23c are sequentially observed while the chip support stand 114 is sequentially rotated by 90 degrees. In this way, the dividing surface of the chip 23 (for example, the dividing surfaces on the four sides of the chip 23) is observed, and the surface roughness of the dividing surface is detected.

As described above, the chip 23 whose divided surface has been observed by the detection mechanism 100 and whose surface roughness has been detected is again picked up by the collet 76 and placed on the base of the inspection unit 2 as shown in FIG. The chips are transported to a predetermined location on a chip tray 501 provided near the chip support stand 114.

In addition to the configuration shown in FIG. 7A described above, as shown in FIG. The divided surfaces 23a, 23b, and 23c (four divided surfaces in total) of the chip 23 may be arranged to face the detection unit 116 in sequence. According to this configuration, the chip support stand 114 can be omitted, and the throughput of the entire apparatus can be improved. In addition, in this case, since the side surface of the chip 23 can be observed without supporting the chip 23 on the chip support stand 114 (see FIG. 7(A)), the side surface of the chip 23 can be observed by placing the chip 23 on the chip support stand 114. This will prevent the bottom side from being damaged.

Next, a description will be given of how an abnormality of the apparatus is determined based on the detected surface roughness of the divided surface of the chip.
FIG. 8 is a functional block diagram illustrating an example of a device configuration for determining an abnormality, and FIG. 9 is a flowchart illustrating an example of determining an abnormality.
As shown in FIGS. 8 and 9, the controller 601 detects the roughness of the first divided surface using the detection unit 116 (S101), and stores the surface roughness in the storage unit 602 as needed.

Next, the abnormality determining unit 603 executes a program for determining an abnormality, and a pre-stored reference value A of surface roughness is compared with an actual measured value B of the surface roughness of the first divided surface. (S102).

The abnormality determination unit 603 determines that when the actual measurement value B is larger than the value obtained by adding the tolerance value C to the reference value A, that is, when it is determined that the surface roughness is outside the tolerance range compared to the reference value. determines that an abnormality has occurred, and outputs the result to the controller 601 (S103).

Upon receiving the abnormality determination, the controller 601 displays a warning of the occurrence of an abnormality in the dicing unit 302 on the monitor 352 of the dicing unit 302 (FIG. 1) (S104). In addition to this, a warning of the occurrence of an abnormality may be displayed on the monitor 353 (FIG. 1) provided on the exterior cover (not shown) of the inspection unit 2. Alternatively, the warning may be displayed only on the monitor 353 provided in the inspection unit 2, or the warning may be issued from another alarm transmitting unit (speaker, indicator light, etc.) not shown.

The abnormality determination unit 603 determines that when the actual measurement value B is less than the value obtained by adding the tolerance value C to the reference value A, that is, when it is determined that the surface roughness is within the tolerance range compared to the reference value. determines that no abnormality has occurred, and outputs the result to the controller 601. The controller 601 determines whether abnormality determination has been completed for all four division planes for the chip (S105), and if it has not been completed, the controller 601 moves the chip support to detect the next division plane. The chip is rotated by controlling the stand 114 or the collet 76 (S106).

If the controller 601 determines that the abnormality determination has been completed for all four divided surfaces of the chip (S105), it determines that there is no abnormality and determines the surface roughness of the divided surface for the next chip. Detects and determines abnormality.

It should be noted that instead of determining the abnormality for all four dividing surfaces for one chip, the abnormality determination may be made by detecting the surface roughness of only one dividing surface or two dividing surfaces.

Further, an immediate stop value may be set in the abnormality determination unit 603, and if the actual value B exceeds the immediate stop value, a command may be output to the controller 601 to stop the device. .

Further, the controller 601 can monitor the surface roughness of the divided plane in real time by displaying the actual measurement value B on the monitor 353 (FIG. 1). Note that the detection unit 116 may include a camera that captures an image of the divided plane, and in that case, the image captured by the detection unit 116 may be displayed together with the actual measurement value B.

In the manner described above, it is possible to determine an abnormality based on the surface roughness of the dividing surface of the chip. Note that the definition of the parameter of the surface roughness of the divided surface is not particularly limited, and it can be detected by the detection unit 116 (which detects the roughness using the depth of focus of the microscope) as described above. The method is not particularly limited as long as it is possible to determine whether the surface roughness is large or small, in addition to using the value of the surface roughness.

The present invention can be realized as described above.
That is, as shown in FIGS. 1 to 3,
A method for diagnosing a dicing unit 302 that dices a workpiece (chip 23 (FIG. 3)) held by a holding table 318, comprising:
a holding step of holding the workpiece on the holding table 318;
a dicing step in which the workpiece held in the holding step is diced into pieces by the cutting and dicing unit 302;
a detection step of detecting the surface roughness of the dividing surface 23a (FIG. 7(B)) of the workpiece cut into pieces in the dicing step;
After performing the detection step, an abnormality determination step of determining that the dicing unit is abnormal when the surface roughness of the dividing surface is outside a predetermined tolerance range;
This is a method for diagnosing a dicing unit including:

Moreover, as shown in FIGS. 1 and 8,
a dicing unit 302 that dices the workpiece held on a holding table 301;
a detection unit 2 that detects the surface roughness of the dividing surface (FIG. 7(B)) of the workpiece (chip 23 (FIG. 3)) cut into pieces by the dicing unit 302;
a controller 601 (FIG. 8) that controls the detection unit;
A dicing system 301 comprising:
The controller 601 is
The dicing unit 302 compares the surface roughness of the divided surface detected by the detection unit with a preset roughness tolerance range, and when the roughness is outside the predetermined tolerance range, the dicing unit 302 determines that the dicing unit 302 is abnormal. The dicing system includes an abnormality determination unit 603 that determines that there is an abnormality.

As described above, when the surface roughness of the dividing surface of the chip falls outside of the allowable range, it is determined to be abnormal, preventing the formation of chips with low strength, and, in turn, continuing to produce defective devices. It is possible to prevent this from happening.

2 Inspection unit 4a Temporary storage table 5 Transport device 10 Temporary storage mechanism 11 Wafer unit 12 Guide rail 13 Wafer 14 Frame fixing mechanism 15 Device 23 Chip 80 Collet movement mechanism 82 Y-axis movement mechanism 90 Movement block 92 Z-axis movement mechanism 100 Detection mechanism 114 Chip support stand 116 Detection unit 301 Dicing system 302 Dicing unit 353 Monitor 501 Chip tray 601 Controller 602 Storage unit 603 Abnormality determination unit

Claims (4)

A method for diagnosing a dicing unit that dices a workpiece held on a holding table, the method comprising:
a holding step of holding the workpiece on the holding table;
a dicing step in which the workpiece held in the holding step is diced into pieces by the dicing unit;
a detection step of detecting the roughness of the dividing surface of the workpiece divided in the dicing step;
After performing the detection step, an abnormality determination step of determining that the dicing unit is abnormal when the roughness of the divided surface is outside a predetermined tolerance range;
including;
In the detection step, the roughness of at least one of the plurality of dividing surfaces of the workpiece is detected ,
In the detection step,
Supporting the workpiece from below on a chip support stand,
The roughness of the plurality of divided surfaces is sequentially observed while the chip support is sequentially rotated.
A method for diagnosing a dicing unit, characterized by: In the detection step,
Supporting the workpiece from above with a collet,
The roughness of the plurality of dividing surfaces is sequentially observed while the collet is sequentially rotated.
The method for diagnosing a dicing unit according to claim 1, characterized in that: a dicing unit that dices a workpiece held on a holding table;
a detection unit that detects the roughness of the dividing surface of the workpiece cut into pieces by the dicing unit;
a controller that controls the detection unit;
A dicing system comprising:
The controller is
The roughness of the divided surface detected by the detection unit is compared with a preset roughness tolerance range, and when the roughness is outside the predetermined tolerance range, the dicing unit is determined to be abnormal. It includes an abnormality judgment section that
The detection unit detects the roughness of at least one of the plurality of dividing surfaces of the workpiece,
The dicing system further includes:
It has a chip support stand that supports the workpiece from below,
Sequentially observing the roughness of the plurality of dividing surfaces while sequentially rotating the chip support;
A dicing system characterized by: It has a collet that supports the workpiece from above,
Sequentially observing the roughness of the plurality of dividing surfaces while sequentially rotating the collet;
The dicing system according to claim 3 , characterized in that: