JP6474233B2 - Frame unit - Google Patents

Description

  The present invention relates to a frame unit in which a dressing board is mounted on an annular frame via a dicing tape.

  In order to reduce the size of semiconductor chips and improve the bending strength, a processing method called a pre-dicing method is known. In normal semiconductor wafer division by dicing, the wafer is fixed in advance to the dicing tape attached to the annular frame so as to block the opening of the annular frame, and the chip is still attached to the dicing tape after division. It is designed not to fall apart.

  However, in the case of the prior dicing method, dicing is intended to form grooves and is not formed into chips, so that the wafer is not supported by the annular frame via the dicing tape. Therefore, processing is performed by a dicing apparatus (cutting apparatus) provided with a conveying means specialized for conveying a semiconductor wafer (see, for example, Japanese Patent No. 4303401).

  In the dicing of a workpiece such as a wafer including the pre-dicing method, a dressing operation of the cutting blade is performed in order to condition the cutting blade. At that time, the dressing board is cut in order to quickly adjust the condition of the cutting blade (see, for example, Japanese Patent No. 5498857).

  Since the dressing board is generally rectangular, the dressing board cannot be conveyed by the conveying means in the dicing apparatus for the first dicing. Therefore, an auxiliary chuck table dedicated to the dressing board is provided beside the chuck table, the dressing board is always held by the auxiliary chuck table, and the dressing board is cut with a cutting blade as necessary.

Japanese Patent No. 4303401 Japanese Patent No. 5498857

  However, in order to provide an auxiliary chuck table dedicated to a dressing board as in the conventional apparatus, it is necessary to modify a normal dicing apparatus, so that there is a problem that it takes cost and modification time and cannot be easily implemented.

  The present invention has been made in view of these points, and the object of the present invention is to allow the dressing board to be transported from the cassette to the chuck table without further modification of the apparatus and to be held by the chuck table. To provide a frame unit.

According to the first aspect of the present invention, a cassette mounting area for mounting a chuck table for holding a wafer, a cutting means for cutting the wafer held by the chuck table with a cutting blade, and a cassette for storing a plurality of wafers. A frame unit used in a cutting apparatus comprising: a cassette mounted on the cassette mounting area; and a transfer unit configured to transfer a wafer between the chuck table and the chuck table. A frame, a dicing tape whose outer peripheral portion is attached to the annular frame so as to close the opening of the annular frame, and a dressing board attached to the dicing tape, and the annular frame of the frame unit is , diameter Ri diameter equal der of the wafer, the annular frame is thin than the dressing board Is formed, the thickness of the annular frame, the frame unit is provided, characterized in that is less than the thickness of the uncut portion of the dressing board to be left off when dressing the cutting blade.

According to a second aspect of the present invention, a cassette mounting area for mounting a chuck table for holding a wafer, a cutting means for cutting the wafer held on the chuck table with a cutting blade, and a cassette for storing a plurality of wafers. A frame unit used in a cutting apparatus comprising: a cassette mounted on the cassette mounting area; and a transfer unit configured to transfer a wafer between the chuck table and the chuck table. A frame, a dicing tape whose outer peripheral portion is attached to the annular frame so as to close the opening of the annular frame, and a dressing board attached to the dicing tape, and the annular frame of the frame unit is is equivalent to the diameter of the diameter the wafer, the cutting device wafer disposed a wafer Mark detecting means for detecting a first mark portion indicating a mark, and the transfer means places the wafer on the chuck table while adjusting the detected first mark portion in a predetermined direction. , the frame unit is provided, which comprises have a second marker portion corresponding to the first mark portion.

  In the frame unit of the present invention, since the annular frame of the frame unit for supporting the dressing board is formed with the same diameter as the wafer, the dressing board is chucked from the cassette without requiring modification of the apparatus even in the dicing for the previous dicing. It can be transported to a table and can be sucked and held by a chuck table.

  Therefore, without providing a dedicated auxiliary chuck table for holding the dressing board, the frame unit is transported to the chuck table and held by the chuck table even in the dicing apparatus for the previous dicing, and the cutting blade can be easily cut by the dressing board of the frame unit. Can be dressed.

It is a perspective view of the cutting device which can apply the frame unit of the present invention. It is sectional drawing of the state by which the cassette mounting mechanism was lowered | hung. It is sectional drawing of the state in which the cassette mounting mechanism was raised. It is a perspective view of an alignment mechanism. It is principal part sectional drawing of an alignment mechanism. 6A is a perspective view of the frame unit according to the embodiment of the present invention, and FIG. 6B is a cross-sectional view thereof. It is a partial cross section side view of the state which is dressing the cutting blade with the dressing board of a frame unit.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, a perspective view of a cutting device (dicing device) 2 suitable for application of the frame unit of the present invention is shown. This cutting apparatus 2 is particularly suitable for forming a cutting groove on a wafer by a tip dicing method.

  Reference numeral 4 denotes a base of a cutting apparatus. A chuck table 6 is reciprocally moved in the X-axis direction by a cutting feed mechanism (not shown) and is rotatable by a rotating mechanism (not shown). A bellows 8 covers the cutting feed mechanism.

  A cassette mounting mechanism 10 is disposed on the side surface of the base 4. The cassette mounting mechanism 10 includes a cassette mounting table 14 slidably disposed on a pair of guide rails 12 provided on the side surface of the base 4 in the vertical direction, and a cassette mounting table 14 disposed below the cassette mounting table 14. A positioning mechanism 16 that aligns the crystal orientation of a semiconductor wafer (hereinafter simply referred to as a wafer) that is a workpiece, and the cassette mounting table 14 and the positioning mechanism 16 are moved along the guide rail 12 in the vertical direction ( A lifting mechanism 18 that moves in the Z-axis direction) is included.

  In the present embodiment, the cassette mounting table 14 and the housing 20 of the alignment mechanism 16 are integrally configured. That is, as shown in FIGS. 2 and 3, the cassette mounting table 14 is configured from the upper wall of the housing 20.

  On the cassette mounting table 14, a cassette 22 for storing a wafer as a workpiece is placed. As shown in FIGS. 2 and 3, the cassette 22 is provided with a workpiece loading / unloading opening 22a for loading and unloading the wafer 11 as a workpiece, and the wafer 11 is placed on the inner surface of the side wall 22b. A plurality of shelves 24 for placement are provided facing the up and down direction.

  The wafer 11 accommodated in the cassette 22 is formed in a disk shape, and a large number of devices 13 such as IC and LSI are formed on the surface thereof. A notch (first mark portion) 15 indicating the crystal orientation of the semiconductor wafer 11 made of silicon is formed on the outer periphery of the wafer 11.

  The alignment mechanism 16 disposed on the lower side of the cassette mounting table 14 includes a housing 20 in which the cassette mounting table 14 forms an upper wall. As shown in FIGS. 2 and 3, the housing 20 is formed with a workpiece carry-in / out opening 20 a for taking in and out the wafer 11.

  A center table 26 on which the wafer 11 is placed is disposed in the housing 20. The center table 26 is appropriately rotated by a pulse motor 28. The center table 26 is selectively connected to a negative pressure suction source, and negative pressure is appropriately applied to the surface thereof.

  The alignment mechanism 16 further includes a center alignment member 30 on the opposite side of the workpiece carry-in / out opening 20a with respect to the center table 26. As shown in FIGS. 4 and 5, the center alignment member 30 includes two circular arc surfaces 32 a and 32 b as position restricting portions that come into contact with a part of the outer peripheral surface of the wafer 11 on the side surface on the center table 26 side. ing.

  The upper arc surface 32a has a radius corresponding to, for example, the radius of an 8-inch semiconductor wafer, and the lower arc surface 32b has an radius corresponding to, for example, the radius of a 12-inch semiconductor wafer. .

  The center alignment member 30 formed in this way is disposed so that the arc surfaces 32 a and 32 b are concentric with the center of rotation of the center table 26. The center alignment member 30 is moved in the vertical direction by a pair of air cylinders 34.

  As shown in FIG. 4, the alignment mechanism 16 detects notches of a semiconductor wafer disposed at a position displaced by 90 ° in the circumferential direction from the intermediate position between the arcuate surfaces 32 a and 32 b provided on the center alignment member 30. Means (mark detection means) 72 is provided.

  The semiconductor wafer notch detecting means 72 includes a light emitting element 76a for an 8-inch semiconductor wafer and a light emitting element 80a for a 12-inch semiconductor wafer disposed on the lower surface of the plate 74. Furthermore, a light receiving element 76b disposed on the upper surface of the plate 78 to face the light emitting element 76a and a light receiving element 80b disposed to face the light emitting element 80a are included.

  As shown in FIGS. 2 and 3, the cassette mounting mechanism 10 configured as described above is fixed to a support base 38 on which the bottom wall 20 b of the housing 20 of the alignment mechanism 16 is lifted and lowered by the lifting mechanism 18. Yes.

  The elevating mechanism 18 includes a ball screw 40 and a pulse motor 42 that can be rotated forward and reversely connected to one end (lower end) of the ball screw 40, and a nut 44 fixed to a base end portion 38 a of the support base 38. Is screwed into the ball screw 40.

  Therefore, when the pulse motor 42 is rotated forward, the ball screw 40 is rotated in one direction and the support base 38 is guided and raised by the guide rail 12, and when the pulse motor 42 is reversed, the ball screw 40 is rotated in the other direction. Then, the support base 38 is guided by the guide rail 12 and descends.

  Referring again to FIG. 1, a portal-shaped first column 46 is erected on the rear side of the base 4, and the first cutting unit 48 </ b> A and the second cutting unit 48 </ b> B are arranged in the Y-axis direction on the first column 46. It is attached to be movable in the Z-axis direction. The first and second cutting units 48A and 48B include a cutting blade 50 attached to the tip of a spindle that is rotationally driven.

  A gate-shaped second column 52 is erected in an intermediate portion of the base 4. A pair of guide rails 54 and 56 are fixed to the second column 52. Reference numeral 58 denotes a workpiece carry-in / out unit (first transport unit), which includes a support member 60 that is suspended from the guide rail 54 and moved in the Y-axis direction, and an arm 62 that is formed integrally with the support member 60. Composed. A suction port 64 for sucking and holding a workpiece is formed on the surface of the arm 62.

  The moving mechanism in the Y-axis direction of the workpiece loading / unloading unit 58 is constituted by, for example, a ball screw and a pulse motor connected to one end of the ball screw, but details of the moving mechanism are omitted in FIG. The workpiece unloading unit 58 unloads the semiconductor wafer 11 that is a workpiece accommodated in the cassette 22 and loads the semiconductor wafer 11 after the cutting into the cassette 22.

  A second transport unit 66 is mounted on the guide rail 56 so as to be movable in the Y-axis direction by a moving mechanism (not shown). This moving mechanism is composed of, for example, a ball screw and a pulse motor connected to one end of the ball screw, but details thereof are omitted in FIG.

  The second conveyance unit 66 sucks and holds the workpiece carried out from the cassette 22 by the workpiece carry-in / out unit (first conveyance unit) 58, conveys it to the chuck table 6, and places it on the chuck table 6. To do.

  Since the cutting device 2 of this embodiment is a cutting device used for the tip dicing method, a clamp for fixing an annular frame for supporting the wafer via the dicing tape is not provided around the chuck table 6. .

  The second transport unit 66 further transports the workpiece after cutting from the chuck table 6 to the spinner table 70 of the spinner cleaning unit 68, and the workpiece subjected to spin cleaning and spin drying by the spinner cleaning unit 68. Delivered to the workpiece carry-in / out unit 58.

  Referring to FIG. 6A, a perspective view of a frame unit 82 according to the embodiment of the present invention is shown. FIG. 6B is a cross-sectional view of the frame unit 82. The frame unit 82 includes an annular frame 88 having the same outer diameter as that of the wafer 11.

  The frame unit 82 includes an annular frame 88, a dicing tape 86 having an outer peripheral portion attached (attached) to the annular frame 88 so as to close the opening of the annular frame 88, and a dressing board 84 attached to the dicing tape 86. Composed.

  The annular frame 88 has a mark portion 89 corresponding to the notch 15 of the wafer 11 shown in FIG. When the dressing board 84 is attached to the dicing tape 86, the dressing board 84 is attached to the dicing tape 86 so that two opposing sides of the rectangular dressing board 84 are orthogonal to the direction of the mark portion 89 of the annular frame 88. It is preferable to stick.

  The annular frame 88 is formed thinner than the dressing board 84, and the thickness of the annular frame 88 is preferably less than the thickness of the uncut portion of the dressing board 84 that is left uncut when the cutting blade 50 is dressed.

  Next, the processing operation of the cutting device 2 configured as described above will be described. Prior to starting the cutting of the wafer 11, a cassette 22 containing a predetermined number of wafers 11 before processing is placed on the cassette mounting table 14.

  When a cutting start switch (not shown) is turned on, the lifting mechanism 18 of the cassette mounting mechanism 10 is operated to lower the cassette mounting mechanism 10 to the position shown in FIG. The arm 62 of the insertion unit 58 is positioned between a pair of shelves 24 adjacent to each other in the vertical direction of the cassette 22.

  After positioning in this way, the arm 62 of the workpiece loading / unloading unit 58 enters the cassette 22, negative pressure is applied to the suction port 62, the wafer 11 is sucked and held by the arm 62, and the arm 62 is moved backward. Then, the wafer 11 is unloaded from the cassette 22.

  Next, the lifting mechanism 18 is operated to raise the cassette placing mechanism 10 to the position shown in FIG. Then, the arm 62 of the workpiece loading / unloading unit 58 is inserted into the housing 20 of the alignment mechanism 16 to position the wafer 11 on the center table 26. At this time, a part of the outer peripheral surface of the wafer 11 is brought into contact with the circular arc surface 32a or 32b of the center alignment member 30, and the center alignment of the wafer 11 is performed.

  That is, when the wafer 11 is 8 inches, the center alignment member 30 is positioned at a position indicated by a solid line in FIG. 5, and a part of the outer peripheral surface of the wafer 11 comes into contact with the arc surface 32a. On the other hand, when the wafer 11 is 12 inches, the center alignment member 30 is raised to the position indicated by the two-dot oblique line in FIG. 5, and a part of the outer peripheral surface of the wafer 11 comes into contact with the arc surface 32b.

  When the center alignment of the wafer 11 is performed in this way, the suction holding of the wafer 11 by the arm 62 is released, and the wafer 11 is sucked and held on the center table 26.

  Next, the alignment mechanism 16 performs alignment of the crystal orientation of the wafer 11. That is, the motor 28 is driven to rotate the center table 26, and a pair of the light emitting element 76a and the light receiving element 76b disposed at a position corresponding to the size of the wafer 11 or a pair of the light emitting element 80a and the light receiving element 80b. However, by stopping the drive of the motor 28 at the position where the notch 15 provided on the outer periphery of the wafer 11 is detected, the notch 15 indicating the crystal orientation of the wafer 11 is aligned with a predetermined position.

  In this way, when the alignment of the notch 15 of the wafer 11 is performed, the center table 26 is rotated by 90 ° to release the suction holding of the wafer 11. Then, the wafer 11 is sucked and held by the arm 62 of the workpiece carry-in / out unit 58.

  After unloading the wafer 11 from the alignment mechanism 16 by the workpiece loading / unloading unit 58, the second transfer unit 66 is moved onto the wafer 11 held by the arm 62 of the workpiece loading / unloading unit 58, and the second transfer unit 66 is moved. The wafer 11 is sucked and held by the transfer unit 66, and the wafer 11 is placed on the chuck table 6.

  Since the workpiece carry-in / out unit 58 and the second transfer unit 66 are configured to be movable only in the Y-axis direction, the wafer 11 is placed on the chuck table 6 with the notch 15 facing the Y-axis direction. The

  When the wafer 11 is sucked and held by the chuck table 6 and a cutting groove that does not completely cut the wafer 11 is continuously formed on the surface of the wafer 11 by the cutting blade 50, the cutting blade 50 is gradually worn. When the cutting blade 50 is worn more than a predetermined amount, dressing of the cutting blade 50 is required.

  In the cutting apparatus 2 of the present embodiment, since the dressing board 84 is supported via the dicing tape 86 by the annular frame 88 of the frame unit 82 having the same outer diameter as that of the wafer 11, the frame unit 82 is previously placed in the cassette. It is accommodated in 22 predetermined shelves 24.

  When the cutting blade 50 needs to be dressed, the frame unit 82 is unloaded from the cassette 22 by the arm 62 of the workpiece loading / unloading unit 58 and the alignment mechanism 16 aligns the wafer 11 described above. The mark portion 89 of the frame unit 82 is detected and the frame unit 82 is aligned at a predetermined position in the same manner as in the above. Next, the center table 26 is rotated 90 ° to release the suction and holding of the frame unit 82.

  Next, the frame unit 82 is pulled out from the alignment mechanism 16 by the arm 62 of the workpiece carry-in / out unit 58, delivered to the second transport unit 66, and the frame unit 82 is placed on the chuck table 6 by the second transport unit 66. When 82 is placed, the frame unit 82 is placed on the chuck table 6 with the mark portion 89 of the frame unit 82 facing the Y-axis direction.

  When the frame unit 82 is thus placed on the chuck table 6, the frame unit 82 is positioned so that a pair of opposing sides of the rectangular dressing board 84 are orthogonal to the direction of the mark portion 89. Become.

  After the frame unit 82 is positioned and held by the chuck table 6 in this manner, dressing of the cutting blade 50 is performed. That is, as shown in FIG. 7, the electromagnetic valve 90 is switched to the communication position, the suction holding portion 6a of the chuck table 6 is connected to the suction source 92, and the frame unit 82 is sucked and held by the chuck table 6 while rotating at high speed. The cutting blade 50 to be cut is cut into the dressing board 84 to a predetermined depth, and the chuck table 6 is dressed by feeding the chuck table 6 in the X-axis direction in FIG.

  In the cutting apparatus 2 of the present embodiment, the frame unit 82 is sucked and held by the chuck table 6 after adjusting the orientation of the frame unit 82 to a predetermined direction by the alignment mechanism 16, so that the two opposing sides of the dressing board 84 are X Parallel to the axial direction. Therefore, the cutting blade 50 can be dressed by efficiently using the entire surface of the rectangular dressing board 84.

  Further, since the annular frame 88 is formed thinner than the uncut portion of the dressing board 84 left uncut during dressing of the cutting blade 50 so as not to interfere with the cutting blade 50 during dressing, the dressing board 84 that can be supported is formed. Can be increased to the limit of the opening of the annular frame 88.

2 Cutting device 6 Chuck table 10 Cassette mounting mechanism 14 Cassette mounting table 16 Positioning mechanism 18 Lifting mechanism 20 Housing 22 Cassette 26 Center table 30 Center position alignment members 32a and 32b Arc surface 38 Support base 40 Ball screw 42 Pulse motor 46 1st column 48A 1st cutting unit 48B 2nd cutting unit 50 Cutting blade 52 2nd columns 54 and 56 Guide rail 58 Workpiece carrying in / out unit (1st conveyance unit)
64 Arm 66 Second transport unit 72 Notch detection means (mark detection means)
76a, 80a Light emitting element 76b, 80b Light receiving element 82 Frame unit 84 Dressing board 86 Dicing tape 88 Annular frame 89 Marking part

Claims (2)

A chuck table for holding a wafer, a cutting means for cutting the wafer held on the chuck table with a cutting blade, a cassette placement area for placing a cassette for storing a plurality of wafers, and a cassette placement area. A frame unit used in a cutting apparatus comprising: a transfer unit configured to transfer a wafer between the placed cassette and the chuck table;
The frame unit is composed of an annular frame, a dicing tape having an outer peripheral portion attached to the annular frame so as to close the opening of the annular frame, and a dressing board attached to the dicing tape,
Annular frame of the frame unit, Ri equivalent der and diameter of the wafer diameter,
The annular frame is formed thinner than the dressing board, and the thickness of the annular frame is less than the thickness of the uncut portion of the dressing board left uncut when dressing the cutting blade. . A chuck table for holding a wafer, a cutting means for cutting the wafer held on the chuck table with a cutting blade, a cassette placement area for placing a cassette for storing a plurality of wafers, and a cassette placement area. A frame unit used in a cutting apparatus comprising: a transfer unit configured to transfer a wafer between the placed cassette and the chuck table;
The frame unit is composed of an annular frame, a dicing tape having an outer peripheral portion attached to the annular frame so as to close the opening of the annular frame, and a dressing board attached to the dicing tape,
The annular frame of the frame unit has a diameter equal to the diameter of the wafer;
The cutting apparatus includes mark detection means for detecting a first mark portion indicating the orientation of the wafer disposed on the wafer, and the transfer means adjusts the detected first mark portion to a predetermined direction while the wafer is being adjusted. Is placed on the chuck table,
The annular frame has a second mark portion corresponding to the first mark portion.