Ultraviolet irradiation apparatus

Abstract

To provide an ultraviolet irradiation device capable of easily picking up a chip without inclination by selecting an area of ultraviolet irradiation.SOLUTION: An ultraviolet irradiation device (40) provided with a holding table (10) for holding a work set which is obtained by bonding a dicing tape to a ring frame and a work and integrating the ring frame and the work, a bar-shaped ultraviolet irradiation unit (42) in which a plurality of ultraviolet light emitting sections are arranged in a straight line parallel to the upper surface of the holding table (10), and a Y-axis moving mechanism (50) for relatively moving the ultraviolet irradiation unit (42) and the holding table (10) parallel to the upper surface of the holding table (10) is provided with an area setting section (60) for setting an area in which the adhesive strength of the dicing tape is reduced, and a control section (70) for controlling at least the ultraviolet irradiation unit (42) or the Y-axis moving mechanism (50) so that ultraviolet rays are irradiated from the ultraviolet irradiation unit (42) toward the area set by the area setting section (60).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an ultraviolet irradiation device that reduces the adhesive strength of a dicing tape by irradiating ultraviolet light onto the dicing tape of a work set that integrates a ring frame and a work with dicing tape attached thereto. [Background technology]

[0002] For example, in a cutting device for cutting a thin, disc-shaped wafer as a workpiece, a dicing tape is attached to a ring frame and a workpiece placed in the opening of the ring frame, and the integrated workpiece set is held on a holding table.The wafer in the workpiece set is then cut along a grid-like planned dividing line with a cutting blade to obtain multiple semiconductor chips.

[0003] The multiple semiconductor chips separated by cutting the wafer are supported on a ring frame via dicing tape and transported to the next process, the die bonding process, where they are picked up one by one from the dicing tape by a die bonder and attached to a designated position on a lead frame or package.

[0004] To facilitate the pick-up of semiconductor chips by the die bonder, the dicing tape is made of UV tape, the adhesive strength of which decreases when exposed to ultraviolet (UV) light. After the wafer is cut into multiple semiconductor chips using a cutting device, the dicing tape is irradiated with UV light to reduce the adhesive strength of the dicing tape.

[0005] Here, ultraviolet irradiation devices that irradiate ultraviolet rays toward dicing tape include a type that moves a bar-shaped ultraviolet irradiation unit having multiple ultraviolet light-emitting elements such as light-emitting diodes arranged in a linear manner horizontally (see Patent Document 1), and a type that rotates a bar-shaped ultraviolet irradiation unit in a horizontal plane around one end of its longitudinal direction (see Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-329300 [Patent Document 2] International Publication No. WO2008 / 142975 Summary of the Invention [Problem to be solved by the invention]

[0007] However, because the workpiece has a depression due to an engraving or the like formed on the surface (back surface) to which the dicing tape is attached, a gap may form between the depression and the dicing tape, and air may enter this gap. If air enters the gap between the depression on the back surface of the workpiece and the dicing tape, when ultraviolet light is irradiated over the entire area of ​​the workpiece by the ultraviolet irradiation unit, the adhesive strength of the dicing tape decreases less in the areas where air is present and decreases more in the areas where air is not present. As a result, when picking up the semiconductor chips obtained by cutting the workpiece, the semiconductor chips become difficult to separate from the dicing tape, or the semiconductor chips may tilt.

[0008] The present invention has been made in consideration of the above problems, and its purpose is to provide an ultraviolet irradiation device that makes it possible to easily pick up semiconductor chips without tilting them by selecting the area to be irradiated with ultraviolet rays. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the present invention provides an ultraviolet irradiation device comprising: a holding table that holds a work set formed by integrating a ring frame and a work placed in the opening of the ring frame with dicing tape adhered thereto; a bar-shaped ultraviolet irradiation unit having a plurality of ultraviolet light-emitting units arranged in a straight line parallel to the upper surface of the holding table; and a moving mechanism that moves the ultraviolet irradiation unit and the holding table relatively parallel to the upper surface of the holding table, wherein the device is characterized by comprising an area setting unit that sets an area in which the adhesive strength of the dicing tape is reduced; and a control unit that controls at least one of the ultraviolet irradiation unit and the moving mechanism so that ultraviolet light is irradiated from the ultraviolet irradiation unit toward the area set by the area setting unit. [Effects of the Invention]

[0010] According to the present invention, the area setting unit sets the region of the dicing tape adhered to the ring frame as the area to be irradiated with ultraviolet light, and the control unit controls the ultraviolet light irradiation unit to irradiate the set area with ultraviolet light, thereby reducing the adhesive strength of the dicing tape to the ring frame, which makes it easy to peel the dicing tape and the workpiece from the ring frame when picking up a chip.

[0011] The outer edge of the dicing tape peeled from the ring frame is then clamped and expanded radially outward, dividing the workpiece into individual semiconductor chips, and the divided semiconductor chips can be picked up. Here, the control unit controls the amount of ultraviolet light irradiated to the area including the workpiece other than the area set by the area setting unit to be low or not irradiated at all, thereby preventing a decrease in the adhesive strength of the dicing tape to the workpiece. Therefore, even if air gets into the gap between the recess and the dicing tape in a workpiece with a recess on its backside, the workpiece and the dicing tape are firmly adhered together. Therefore, tilting of the chip due to differences in adhesive strength can be prevented. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view of a cutting device equipped with an ultraviolet irradiation device according to the present invention. [Figure 2] FIG. [Figure 3] 1 is a perspective view of an ultraviolet irradiation device according to the present invention. [Figure 4] 1A and 1B are diagrams illustrating the operation of the ultraviolet irradiation device according to the first embodiment of the present invention, in which (a) is a plan view of the ultraviolet irradiation unit and the work set, and (b) is a diagram illustrating the relationship between the position of the ultraviolet irradiation unit in the Y-axis direction and the moving speed. [Figure 5] 4 is a flowchart showing the operation of the ultraviolet irradiation device according to the first embodiment of the present invention. [Figure 6] 10(a) to 10(c) are side cross-sectional views showing the process of dividing the chips by expanding the dicing tape and picking them up. [Figure 7] 10A and 10B are diagrams illustrating the operation of an ultraviolet irradiation device according to a second embodiment of the present invention, in which (a) is a plan view of an ultraviolet irradiation unit and a work set, and (b) is a diagram illustrating the relationship between the position of the ultraviolet irradiation unit in the Y-axis direction and the power supplied to the ultraviolet irradiation unit. [Figure 8] 10 is a flowchart showing the operation of the ultraviolet irradiation device according to the second embodiment of the present invention. [Figure 9] FIG. 10 is a plan view of an ultraviolet irradiation unit and a work set, illustrating the operation of an ultraviolet irradiation device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0014] [Cutting equipment configuration] First, the overall configuration of a cutting device equipped with an ultraviolet irradiation device according to the present invention will be described below with reference to Fig. 1. In the following description, the left-right direction in Fig. 1 will be referred to as the "X-axis direction," the front-rear direction as the "Y-axis direction," and the up-down direction as the "Z-axis direction."

[0015] The cutting device 1 shown in FIG. 1 is a so-called dual dicer, and includes as its main components a holding table 10 that holds a plurality of work sets WS (see FIG. 2) including thin rectangular workpieces W as workpieces, a cutting mechanism 20 that cuts the workpieces W held on the holding table 10, a spinner cleaning mechanism 30 that cleans the workpieces W after cutting, an ultraviolet irradiation device 40 that irradiates ultraviolet (UV) rays toward the work sets WS including the cleaned workpieces W, an area setting unit 60 (see FIG. 3) that sets an area to be irradiated with ultraviolet rays by the ultraviolet irradiation device 40, a control unit 70 (see FIG. 3) that controls the ultraviolet irradiation unit 42 of the ultraviolet irradiation device 40, and a transfer mechanism 90 that transfers the work sets WS to and from a cassette (not shown) or the ultraviolet irradiation device 40. The ultraviolet irradiation device 40 is configured to include the area setting unit 60 and the control unit 70.

[0016] The cutting device 1 shown in Figure 1 also includes, as other components, a cassette (not shown) for storing the work set WS, a pair of frame guides 71 for temporarily placing the work set WS, a first conveying mechanism 72 for transporting the work set WS temporarily placed on the frame guides 71 to the holding table 10, and a second conveying mechanism 73 for transporting the work set WS from the holding table 10.

[0017] As shown in Figure 2, the surface of the workpiece W is divided into a large number of rectangular areas by mutually orthogonal grid-like division lines L1 and L2 called streets, and devices D such as ICs and LSIs are formed in each rectangular area. Recesses P are formed on the back surface of each rectangular area by engraving or the like. The recesses P are formed in a cylindrical or groove shape, and allow air to enter between the workpiece W and the dicing tape T.

[0018] Thus, a workpiece W on which numerous devices D have been formed is cut along planned division lines L1 and L2 (see FIG. 2) as described below to form a plurality of chips C (see FIG. 6(c)). As shown in FIG. 2, the workpiece W is placed in the opening of an annular ring frame F, and a thin, circular dicing tape T is attached to the backside of the workpiece W and the ring frame F to unite them, thereby forming a workpiece set WS. Here, the dicing tape T is a so-called UV tape, whose adhesive strength decreases when exposed to ultraviolet light. Note that, as described below, when the workpiece W is transported or cut, the workpiece set WS is transported together with the workpiece W and held on the holding table 10 or the spinner table 31 (described below) of the spinner cleaning mechanism 30.

[0019] Next, the configurations of the main elements constituting the cutting device 1, namely, the holding table 10, the cutting mechanism 20, the spinner cleaning mechanism 30, the ultraviolet irradiation device 40, the area setting unit 60, the control unit 70 and the carry-in / out mechanism 90 will be described.

[0020] (holding table) The holding table 10 is a disk-shaped member that holds the work set WS, and is arranged so that its holding surface (upper surface) is exposed to an opening in the upper surface of the base 100. Four clamps 11 (only three are shown in FIG. 1) are arranged around the periphery of the holding table 10 at equal angular intervals (90° intervals) to secure the ring frame F (see FIG. 2) of the work set WS from all four sides.

[0021] Here, the holding table 10 is rotated around a vertical axis by a rotation mechanism (not shown) arranged below it, and can also be moved back and forth along the X-axis direction (left and right direction) by an X-axis movement mechanism (not shown) arranged below it.

[0022] (cutting mechanism) The cutting device 1 according to this embodiment, which is a dual dicer, includes a cutting mechanism 20 consisting of a first cutting unit 21 and a second cutting unit 22 arranged side by side on the left side (-X-axis side) of a base 100. The first cutting unit 21 and the second cutting unit 22 are disposed facing each other on both the front and rear sides (-Y-axis side and +Y-axis side) of an opening in the top surface of the base 100, respectively. An imaging unit 23 is attached to each of the first cutting unit 21 and the second cutting unit 22. Each imaging unit 23 captures an image of the surface of the workpiece W held on the holding surface of the holding table 10 to detect the positions of the intended division lines L1 and L2 (see FIG. 2). Each of the first cutting unit 21 and the second cutting unit 22 is provided with a disk-shaped cutting blade 24 (only one of which is shown in FIG. 1) that is rotated at high speed by a spindle motor (not shown).

[0023] In addition, the first cutting unit 21 and the second cutting unit 22 can be moved up and down in the Z-axis direction (cutting feed direction) by a pair of front and rear Z-axis moving mechanisms 80, and can be moved back and forth in the Y-axis direction (indexing feed direction) by a pair of front and rear Y-axis moving mechanisms 2.

[0024] Here, each Z-axis movement mechanism 80 is configured to include a pair of Z-axis guide rails 81 arranged vertically and parallel to each other at the front and rear of the rectangular plate-shaped slider 3, a lifting plate 82 that can move up and down along these Z-axis guide rails 81, a rotatable Z-axis ball screw 83 that is arranged vertically between the pair of Z-axis guide rails 81, and a Z-axis servo motor 84 that can rotate forward and backward and rotates the Z-axis ball screw 83. The first cutting unit 21 and imaging unit 23 and the second cutting unit 22 and imaging unit 23 are attached to the lower part of each lifting plate 82. Note that a nut member (not shown) protrudes from the back surface of each lifting plate 82, and the Z-axis ball screw 83 is threadedly inserted into this nut member.

[0025] In the Z-axis movement mechanism 80 configured as described above, when the Z-axis servo motor 84 is started and the Z-axis ball screw 83 rotates forward and backward, the lifting plate 82, which has a protruding nut member (not shown) that screws onto the Z-axis ball screw 83, moves up and down along a pair of Z-axis guide rails 81, and the first cutting unit 21 and imaging unit 23 and the second cutting unit 22 and imaging unit 23 attached to each lifting plate 82 also move up and down along the Z-axis direction (cutting feed direction).

[0026] Each of the pair of front and rear Y-axis moving mechanisms 2 is equipped with the slider 3, and these sliders 3 can move along the Y-axis direction along a pair of upper and lower Y-axis guide rails 4 arranged parallel to each other along the Y-axis direction (front-back direction) in front of a gate-shaped column 101 that is erected vertically on the base 100.

[0027] In the pair of front and rear Y-axis movement mechanisms 2, a pair of upper and lower rotatable Y-axis ball screws 5 are arranged along the Y-axis direction (front and rear direction) between the pair of upper and lower Y-axis guide rails 4, and these Y-axis ball screws 5 are threadedly engaged with nut members (not shown) that protrude from the back surface of each of the pair of front and rear sliders 3. One axial end of each Y-axis ball screw 5 is connected to a Y-axis servo motor 6 (only one of which is shown in FIG. 1) that serves as a rotational drive source.

[0028] Therefore, in each Y-axis movement mechanism 2, when the Y-axis servo motor 6 is started to rotate the Y-axis ball screws 5 forward and backward, the pair of front and rear sliders 3, from which nut members (not shown) that screw onto these Y-axis ball screws 5 protrude, can move in the Y-axis direction (indexing feed direction) along the Y-axis guide rail 4 together with the lifting plate 82. As a result, the first cutting unit 21 and imaging unit 23 and the second cutting unit 22 and imaging unit 23, each attached to the lifting plate 82, can move in the Y-axis direction (indexing feed direction) along the Y-axis guide rail 4.

[0029] As described above, in the cutting device 1 shown in Figure 1, the holding table 10 and the work set WS held thereon are movable along the X-axis direction (left-right direction), and the first cutting unit 21 and the imaging unit 23 and the second cutting unit 22 and the imaging unit 23 are movable along the Y-axis direction (front-back direction) and the Z-axis direction (up-down direction), respectively.

[0030] (Spinner cleaning mechanism) The spinner cleaning mechanism 30 is used to clean the workpiece W after cutting, and is disposed rearward and to the right of the opening on the base 100, as shown in Fig. 1. The spinner cleaning mechanism 30 includes a spinner table 31 that rotates while holding the workpiece set WS by suction, and a spray nozzle (not shown) that sprays a cleaning liquid from above onto the workpiece W of the workpiece set WS held by suction on the spinner table 31. Pure water is preferably used as the cleaning liquid.

[0031] (Ultraviolet irradiation device) The ultraviolet irradiation device 40 is a unit that irradiates ultraviolet rays toward the work set WS to reduce the adhesive strength of the dicing tape T, and is disposed at the -Y-axis direction end of the base 100, as shown in FIG. 1. As shown in FIG. 3, the ultraviolet irradiation device 40 is configured to accommodate, within a rectangular case 41, an ultraviolet irradiation unit 42 that is movable in the Y-axis direction and has a bar shape that is long in the X-axis direction, a Y-axis movement mechanism 50 for moving the ultraviolet irradiation unit 42 back and forth along the Y-axis, and a pair of mounting rails 43 for mounting the work set WS. As shown in FIG. 1, a rectangular opening 41a is formed in the +Y-axis direction end face (rear wall) of the case 41 to allow the work set WS to pass through. The top plate of the case 41 is a cassette stage for mounting a cassette (not shown).

[0032] 3, a plurality of (21 in the illustrated example) light-emitting diodes 44, which are ultraviolet light-emitting sections, are linearly arranged at appropriate intervals along the longitudinal direction (X-axis direction) in the ultraviolet irradiation unit 42. When power is supplied to each light-emitting diode 44 from a power source (not shown), each light-emitting diode 44 emits light and emits ultraviolet (UV) rays upward.

[0033] The Y-axis movement mechanism 50 also includes a pair of guide rails 51 that are long in the Y-axis direction and arranged in parallel at a predetermined distance in the X-axis direction, a rotatable ball screw 52 arranged along the X-axis direction, a servo motor 53 that rotates the ball screw 52 forward and backward, and an encoder 54 that detects the direction and number of rotations of the servo motor 53. The encoder 54 is electrically connected to a control unit 70, and when a detection signal from the encoder 54 is sent to the control unit 70, the control unit 70 drives and controls the servo motor 53 based on the received detection signal.

[0034] Both ends of the ball screw 52 in the longitudinal direction (Y-axis direction) are rotatably supported by the case 41 by bearings 55, and a driven pulley 56 is attached to one end of the ball screw 52. A drive pulley 57 is attached to the output shaft (motor shaft) 54a of the servo motor 53, and an endless timing belt 58 is wound around the drive pulley 57 and the driven pulley 56. A nut member 59 is attached to one longitudinal end (positive X-axis direction end) of the ultraviolet irradiation unit 42, and the ball screw 52 is threadedly inserted into the nut member 59.

[0035] Therefore, when the servo motor 53 is started and the output shaft 54a rotates, the rotation is transmitted to the driven pulley 56 via the drive pulley 57 and timing belt 58, and the driven pulley 56 and the ball screw 52 rotate, so that the ultraviolet irradiation unit 42, to which the nut member 59 that threads onto the ball screw 52 is attached, moves along the pair of guide rails 51.

[0036] (Area setting section) 3 is used by an operator to set an area where ultraviolet light is irradiated by the ultraviolet light irradiation device 40 to reduce the adhesive strength of the dicing tape T, and is electrically connected to the control unit 70. The area setting unit 60 may be incorporated into the control unit 70, or may be configured to automatically set an area where the adhesive strength of the dicing tape T is reduced based on the specifications of the work set WS input by the operator.

[0037] (Control unit) 3 includes a CPU (Central Processing Unit) that performs calculations according to a control program, and storage units such as a ROM (Read Only Memory) and a RAM (Random Access Memory). In particular, in this embodiment, the control unit 70 controls an ultraviolet ray irradiation unit that moves continuously in the Y-axis direction in the area set by the area setting unit 60. Device The function of this is to control the moving speed of the ultraviolet irradiation unit 42 in accordance with the position in the Y-axis direction recognized by the encoder 54 of the unit 40, and this will be described in detail later.

[0038] (Carry-in / out mechanism) The carry-in / out mechanism 90 includes a guide rail 91 that is arranged along the Y-axis direction on the side of the base 100 shown in Fig. 1 to support the work set WS (see Fig. 2), a horizontal L-shaped arm 92 that moves in the Y-axis direction along the guide rail 91, a clamp 93 attached to the tip of the arm 92, a ball screw 94 that is threadably inserted into the arm 92 and arranged along the Y-axis direction on the side of the base 100, and a servo motor 95 attached to one longitudinal end of the ball screw 94. The other longitudinal end of the ball screw 94 is rotatably supported by the base 100 via a bearing 96.

[0039] Therefore, when the servo motor 95 is started and the ball screw 94 rotates forward and backward, the arm 92 threaded onto the ball screw 94 moves back and forth along the Y-axis together with the clamp 93, and the work set WS held by the clamp 93 also moves back and forth along the Y-axis, and the work set is inserted into or removed from a cassette (not shown) and the ultraviolet irradiation device 40.

[0040] [Action of cutting device] Next, the operation of the cutting device 1 configured as above will be described.

[0041] When cutting the workpiece W, the workpiece set WS is drawn out from a cassette (not shown) by the carry-in / out mechanism 90, and the drawn-out workpiece set WS is temporarily placed on the pair of frame guides 71.

[0042] As described above, when the work set WS is pulled out from the cassette (not shown) and temporarily placed on the pair of frame guides 71, the work set WS is positioned in the X-axis direction. Then, the first transport mechanism 72 sucks and holds the work set WS, and the work set WS is transferred to the holding table 10 waiting below. Once the work set WS is transferred onto the holding table 10 in this manner, the holding table 10 holding the work set WS is moved in the -X-axis direction by an X-axis movement mechanism (not shown).

[0043] 1, when an image is obtained by imaging the surface of the workpiece W using each imaging unit 23, a planned division line L1 (see FIG. 2) to be cut is detected by pattern matching processing based on the image. When the planned division line L1 of the workpiece W is detected in this way, the positions of the cutting blades 24 (only one of which is shown in FIG. 1) of the first cutting unit 21 and the second cutting unit 22 in the Y-axis direction are respectively determined by each of the pair of front and rear Y-axis moving mechanisms 2, and the positions of these cutting blades 24 in the Y-axis direction are aligned with the position of the planned division line L1 to be cut.

[0044] Then, from the above state, the cutting blades 24 of the first cutting unit 21 and the second cutting unit 22 are each rotated at high speed, and are lowered by a predetermined cutting depth by the pair of front and rear Z-axis movement mechanisms 80, and the holding table 10 and the work set WS held thereon are moved in the X-axis direction by an X-axis movement mechanism (not shown). The workpiece W is then cut along the planned dividing lines L1 by the cutting blades 24 of the first cutting unit 21 and the second cutting unit 22, and after this operation has been performed for all planned dividing lines L1 in one direction, the holding table 10 and the work set WS held thereon are rotated by 90° by a rotation mechanism (not shown), and the workpiece W is similarly cut along the planned dividing lines L2 (see FIG. 2) in the other direction that are perpendicular to the planned dividing lines L1 along which cutting has been completed.

[0045] When cutting of the workpiece W is completed in the above manner, the workpiece set WS held on the holding table 10 is transferred to the second transport mechanism 73. That is, similar to the first transport mechanism 72, the workpiece set WS is transported to the spinner cleaning mechanism 30 while being suction-held by the second transport mechanism 73, and then transferred to the spinner table 31 of the spinner cleaning mechanism 30.

[0046] The work set WS that has been handed over to the spinner table 31 is held by suction on the holding surface of the spinner table 31 and rotates at a predetermined speed together with the spinner table 31 while being washed with cleaning liquid (pure water) sprayed from a spray nozzle (not shown), and cutting chips that have adhered to the workpiece W during the cutting process are removed, completing the series of cutting processes on the workpiece W.

[0047] As described above, when the surface of the work set WS is cleaned by the spinner cleaning mechanism 30, as shown in FIG. 4(a), all of the light-emitting diodes 44 of the ultraviolet irradiation unit 42, which is long in the X-axis direction (the up-down direction in FIG. 4), are lit, and the ultraviolet irradiation unit 42 is moved horizontally along the Y-axis direction by the Y-axis moving mechanism 50.

[0048] In this embodiment, the first area S1 in which the adhesive strength of the dicing tape T is reduced is set as shown in Fig. 4 by the area setting unit 60 shown in Fig. 3. That is, the first area S1 in which the adhesive strength of the dicing tape T is reduced is a region from the initial position (y = 0) of the ultraviolet irradiation unit 42 in the movement direction (Y-axis direction) to a position y2 that is Δy ahead of a Y-axis direction position y3 where the ultraviolet irradiation unit 42 (more precisely, the ultraviolet irradiation position of the light-emitting diode 44) passes one side of the workpiece W, and a region from a position y5 onwards that is Δy behind a Y-axis direction position y4 where the ultraviolet irradiation unit 42 passes the other side of the workpiece W, and the remaining second area S2 is a region in which the reduction in the adhesive strength of the dicing tape T is suppressed.

[0049] Thus, in this embodiment, the control unit 70 increases the movement speed V2 of the ultraviolet irradiation unit 42 in the second area S2, which suppresses a decrease in the adhesive strength of the dicing tape T and maintains the adhesive strength at or above a predetermined value, to be higher than the movement speed V1 of the ultraviolet irradiation unit 42 in the first area S1, which reduces the adhesive strength of the dicing tape T (V2>V1), thereby reducing the amount of ultraviolet radiation irradiated in the second area S2 compared to the amount of ultraviolet radiation irradiated in the first area S1. This will be explained below with reference to the flowchart shown in FIG.

[0050] That is, the control unit 70 supplies power to all the light-emitting diodes 44 of the ultraviolet irradiation unit 42 to light up each of the light-emitting diodes 44 (step S1 in FIG. 5), and controls the Y-axis movement mechanism 50 to move the ultraviolet irradiation unit 42 in the Y-axis direction at a speed V1 (step S2 in FIG. 5). At this time, the encoder 54 detects the Y-axis position y of the ultraviolet irradiation unit 42 (step S3 in FIG. 5), and the control unit 70 42It is determined whether the Y-axis direction position y of the ultraviolet irradiation unit 42 has reached y1 shown in Figure 4(b) (step S4 in Figure 5), and if the Y-axis direction position y of the ultraviolet irradiation unit 42 has not reached y1 (step S4: No), the ultraviolet irradiation unit 42 is moved at a relatively slow speed V1 while the amount of ultraviolet light emitted from all the light-emitting diodes 44 of the ultraviolet irradiation unit 42 that is irradiated onto the dicing tape T is relatively increased, thereby actively reducing the adhesive strength of the dicing tape T that is irradiated with this ultraviolet light.

[0051] When the Y-axis position y of the ultraviolet irradiation unit 42 detected by the encoder 54 reaches y1 shown in FIG. 4(b) (step S4: Yes in FIG. 5), the control unit 70 accelerates the ultraviolet irradiation unit 42 (step S5 in FIG. 5) and determines whether the Y-axis position y of the ultraviolet irradiation unit 42 reaches y2 shown in FIG. 4(b) (step S6 in FIG. 5). When the Y-axis position y of the ultraviolet irradiation unit 42 reaches y2 shown in FIG. 4(b) (step S6: Yes), the control unit 70 sets the movement speed of the ultraviolet irradiation unit 42 to a value V2 (>V1) higher than V1 when the ultraviolet irradiation unit 42 moves from the first area S1 to the second area S2 (step S7 in FIG. 5). Note that when the Y-axis position y of the ultraviolet irradiation unit 42 has not reached y2 shown in FIG. 4(b) (step S6: No), the ultraviolet irradiation unit 42 continues to accelerate until the Y-axis position y of the ultraviolet irradiation unit 42 reaches y2 (see FIG. 4(b)).

[0052] Therefore, while the ultraviolet irradiation unit 42 is moving through the second area S2 containing the workpiece W shown in Figure 4 at a speed V2 faster than speed V1, the amount of ultraviolet light irradiated onto the dicing tape T by the ultraviolet irradiation unit 42 is kept lower than the amount irradiated in the first area S1, and the decrease in adhesive strength of the dicing tape T in the second area S2 is also kept low, so that the workpiece W and the dicing tape T are adhered more strongly together than in the first area S1.

[0053] In the first area S1, the ultraviolet-curable adhesive layer of the dicing tape T is hardened to a hardness that facilitates peeling, and its adhesive strength is reduced to a hardness that facilitates peeling. In contrast, in the second area S2, the adhesive layer is softer than that of the first area S1, and has a higher adhesive strength. In addition, in the second area S2, there are portions where air is trapped between the dicing tape T and the recesses P, and in these portions, the adhesive layer is even softer. In other words, in the second area S2, there are both portions that have hardened to a softer hardness than the adhesive layer in the first area S1 and portions that have hardened to an even softer hardness.

[0054] Thereafter, the control unit 70 determines whether the Y-axis direction position y of the ultraviolet irradiation unit 42 detected by the encoder 54 has reached y5 shown in Fig. 4(b) (step S8 in Fig. 5), and if the Y-axis direction position y of the ultraviolet irradiation unit 42 has reached y5 (step S8: Yes), the control unit 70 decelerates the ultraviolet irradiation unit 42 as shown in Fig. 4(b) (step S9 in Fig. 5). Note that if the Y-axis direction position y of the ultraviolet irradiation unit 42 has not reached y5 (step S8: No), the ultraviolet irradiation unit 42 continues to decelerate.

[0055] The control unit 70 then determines whether the Y-axis position y of the ultraviolet irradiation unit 42 detected by the encoder 54 while decelerating the ultraviolet irradiation unit 42 has reached y6 shown in FIG. 4(b) (step S10 in FIG. 5). If the Y-axis position y of the ultraviolet irradiation unit 42 reaches y6 (step S10: Yes), the control unit 70 returns the movement speed of the ultraviolet irradiation unit 42 to the original low speed V1 (step S11 in FIG. 5), as shown in FIG. 4(b), and terminates the series of controls for the ultraviolet irradiation unit 42 (step S12 in FIG. 5). Note that if the Y-axis position y of the ultraviolet irradiation unit 42 has not reached y6 (step S10: No), the control unit 70 continues to decelerate the ultraviolet irradiation unit 42 until the Y-axis position y of the ultraviolet irradiation unit 42 reaches y6.

[0056] As described above, in this embodiment, the movement speed V1 of the ultraviolet irradiation unit 42 in the first area S1 not including the workpiece W is set to a low value, and the amount of ultraviolet light irradiated onto the dicing tape T by the ultraviolet irradiation unit 42 is relatively large, thereby weakening the adhesive strength of the dicing tape T to the ring frame F in this first area S1. In contrast, in the second area S2 including the workpiece W, the ultraviolet irradiation unit 42 moves at a relatively high speed V2, which keeps the decrease in adhesive strength of the dicing tape T to the workpiece W low and also prevents the hardening of the adhesive layer, resulting in a stronger adhesion between the workpiece W and the dicing tape T than in the first area S1.

[0057] In the above state, the ring frame F and the dicing tape T are gripped, and the portion of the workpiece W corresponding to the chips C is pushed up from below by a pressure rod 110 as shown in Fig. 6(b), thereby expanding the dicing tape T and separating the chips C horizontally as shown in Fig. 6(c), making it easier to pick up the chips C. Then, each chip C can be picked up and mounted in a predetermined position on a lead frame or package (not shown).

[0058] As described above, in this embodiment, the movement speed of the ultraviolet irradiation unit 42 in the second area S2 containing the workpiece W is set faster than the movement speed V1 of the ultraviolet irradiation unit 42 in the first area S1. This reduces the amount of ultraviolet radiation irradiated onto the portion of the dicing tape T affixed to the workpiece W, thereby suppressing hardening of the adhesive layer. This minimizes the difference in hardness of the adhesive layer between the portion where air is trapped between the recess P of the workpiece W and the dicing tape T and the portion where air is not trapped. This prevents adhesive residue from being left on the chip C when the chip C is picked up. Furthermore, in the first area S1, the amount of ultraviolet radiation irradiated onto the portion of the dicing tape T affixed to the ring frame F is increased compared to the amount of ultraviolet radiation irradiated onto the second area S2, thereby hardening the adhesive layer of the dicing tape T and reducing its adhesive strength. This allows the dicing tape T to be easily peeled off from the ring frame F after the chip C is picked up.

[0059] In this embodiment, ultraviolet light may be applied before dicing. Because the amount of ultraviolet light applied to the portion attached to the workpiece W before dicing is reduced, the chips C separated by dicing do not shift, and the adhesive layer is hardened, preventing clogging of the cutting blade 24.

[0060] [Second embodiment of ultraviolet irradiation device] Next, a second embodiment of the ultraviolet irradiation device will be described with reference to Figures 7 and 8. In Figure 7, the same elements as those shown in Figure 4 are denoted by the same reference numerals, and a repeated description of these elements will be omitted below.

[0061] In this embodiment, similarly to the above embodiment, the ultraviolet irradiation unit 42 is configured to irradiate ultraviolet rays while being moved horizontally in the Y-axis direction below the work set WS by the Y-axis movement mechanism 50. 42 The ultraviolet irradiation unit 42 is moved at a constant speed while selectively turning on a plurality of light emitting diodes 44, thereby irradiating ultraviolet light only onto a predetermined area.

[0062] Specifically, in this embodiment, the first area S1 in which the adhesive strength of the dicing tape T is reduced is set as shown in FIG. 7 by the area setting unit 60 shown in FIG. 3. That is, the first area S1 in which the adhesive strength of the dicing tape T is reduced is a region that does not include the workpiece W from the initial position (y=0) of the ultraviolet irradiation unit 42 in the movement direction (Y-axis direction) to a position y1 that is Δy ahead of a Y-axis direction position y2 where the ultraviolet irradiation unit 42 (more precisely, the ultraviolet irradiation position of the light-emitting diode 44) passes over one side of the workpiece W, and a region that does not include the workpiece W from a position y4 in the movement direction that is Δy behind a Y-axis direction position y3 where the ultraviolet irradiation unit 42 passes over the other side of the workpiece W. In addition, a region that includes the workpiece W other than the first area S1 is defined as a second area S2, and ultraviolet light is not irradiated in this second area S2 so as not to reduce the adhesive strength of the dicing tape T to the workpiece W.

[0063] In this embodiment, as shown in FIG. 7(a), in the first area S1 not including the workpiece W, the control unit 70 turns on all of the light-emitting diodes 44 of the ultraviolet irradiation unit 42 to irradiate the dicing tape T with ultraviolet light and reduce the adhesive strength of the dicing tape T, and in the second area S2 including the workpiece W, the control unit 70 does not energize multiple (13 in the illustrated example) light-emitting diodes 44 passing under the workpiece W, turning off these light-emitting diodes 44, and turns on only the remaining multiple (8 in the illustrated example) light-emitting diodes 44 passing under the ring frame F to reduce the adhesive strength of the dicing tape T to the ring frame F, thereby preventing a reduction in the adhesive strength of the dicing tape T to the workpiece W.

[0064] Therefore, as shown in FIG. 7(b), the supply power to the ultraviolet irradiation unit 42 in the first area S1 where all the light-emitting diodes 44 are lit is as high as E2, and the supply power E1 to the ultraviolet irradiation unit 42 in the second area S2 where some of the light-emitting diodes 44 are turned off is lower than the supply power E2 in the first area S1 (E1 < E2). In FIG. 7(a), among the plurality of light-emitting diodes 44, those that are lit are indicated by □, and those that are turned off are indicated by ■.

[0065] Hereinafter, the above content will be described according to the flowchart shown in FIG. 8.

[0066] That is, the control unit 70 supplies the power E2 shown in FIG. 7(b) to all the light-emitting diodes 44 of the ultraviolet irradiation unit 42 to turn on all the light-emitting diodes 44 as shown in FIG. 7(a) (step S21 in FIG. 8), and moves the ultraviolet irradiation unit 42 in the Y-axis direction at a constant speed by the Y-axis moving mechanism 50 (step S22 in FIG. 8). At this time, the Y-axis direction position y of the ultraviolet irradiation unit 42 is detected by the encoder 54 (step S23 in FIG. 8), and the control unit 70 determines whether the detected Y-axis direction position y of the ultraviolet irradiation unit 42 has reached y1 shown in FIG. 7(b) (step S24 in FIG. 8). When the Y-axis direction position y of the ultraviolet irradiation unit 42 has not reached y1 (step S24: No), the operation of moving the ultraviolet irradiation unit 42 at a constant speed with all the light-emitting diodes 44 lit is continued.

[0067] When the Y-axis position y of the ultraviolet irradiation unit 42 detected by the encoder 54 reaches y1 shown in FIG. 7(b) (step S24: Yes in FIG. 8), the control unit 70 turns off a part (13 shown by ■ in FIG. 7(a)) of the plurality of light-emitting diodes 44 of the ultraviolet irradiation unit 42 that pass below the workpiece W (step S25 in FIG. 8), and turns on the remaining (8 shown by □ in FIG. 7(a)) light-emitting diodes 44. The supply power E1 to the ultraviolet irradiation unit 42 at this time is kept lower than the supply power E2 for turning on all the light-emitting diodes 44 (E1 < E2). Therefore, in this embodiment, power saving is achieved.

[0068] Therefore, when the ultraviolet irradiation unit 42 is moving at a constant speed in the second area S2 including the workpiece W, the ultraviolet rays emitted from the ultraviolet irradiation unit 42 are irradiated only on the adhesion part of the ring frame F of the dicing tape T, while the adhesion force of the ring frame F of the dicing tape T decreases. On the other hand, since the workpiece W is not irradiated with ultraviolet rays, the adhesion force of the dicing tape T to the workpiece W does not decrease and the dicing tape T is firmly adhered to the workpiece W.

[0069] Thereafter, the control unit 70 determines whether or not the Y-axis position y of the ultraviolet irradiation unit 42 detected by the encoder 54 has reached y4 shown in FIG. 7(b) (step S26 in FIG. 8). When the Y-axis position y of the ultraviolet irradiation unit 42 reaches y4 (step S26: Yes), the control unit 70 turns on all the light-emitting diodes 44 of the ultraviolet irradiation unit 42 as shown in FIG. 7(a) (step S27 in FIG. 8). A series of controls is terminated (step S28 in FIG. 8). When the Y-axis position y of the ultraviolet irradiation unit 42 has not reached y4 (step S26: No), that is, while the ultraviolet irradiation unit 42 is moving in the second area S2, the turning off of some of the light-emitting diodes 44 continues.

[0070] In this embodiment, all of the LEDs 44 of the ultraviolet irradiation unit 42 are lit in the first area S1, which does not include the workpiece W, to increase the amount of ultraviolet light irradiated onto the dicing tape T. This reduces the adhesive strength of the dicing tape T to the ring frame F. This facilitates peeling of the dicing tape T from the ring frame F. Furthermore, since ultraviolet light is not irradiated in the second area S2, picking up the chips C is difficult. Therefore, in this second embodiment, a relatively small amount of ultraviolet light is irradiated onto the portion attached to the workpiece W before cutting, as in the first embodiment, to harden the adhesive layer while maintaining the adhesive strength that prevents the chips C from shifting. Hardening the adhesive layer before cutting in this way prevents clogging of the cutting blade 24 during cutting and minimizes the difference in hardness of the adhesive layer between the portion where air is trapped between the recess P of the workpiece W and the dicing tape T and the portion where air is not trapped. This prevents adhesive residue from remaining on the chips C when picking up the chips C.

[0071] Then, by clamping the outer peripheral edge of the dicing tape T peeled from the ring frame F and expanding it radially outward, the workpiece W is divided into individual semiconductor chips C, and the divided semiconductor chips C can be picked up. Here, in the second area S2 containing the workpiece W, some of the light-emitting diodes 44 of the ultraviolet irradiation unit 42 are turned off so that ultraviolet light is not irradiated onto the portion of the dicing tape T that is adhered to the workpiece W, thereby preventing a decrease in the adhesive strength of the dicing tape T to the workpiece W. As a result, even if air gets into the gap between the recess P and the dicing tape T in a workpiece W that has a recess P on its back surface, the workpiece W and the dicing tape T are firmly adhered, so tilting of the semiconductor chip C due to differences in adhesive strength is prevented.

[0072] [Third embodiment of ultraviolet irradiation device] Next, a third embodiment of the ultraviolet irradiation device will be described with reference to Fig. 9. In Fig. 9, the same elements as those shown in Fig. 4 are denoted by the same reference numerals, and a repeated description of these elements will be omitted below.

[0073] In this embodiment, the ultraviolet irradiation unit 42 has a base end rotatably supported by a rotation shaft 45, and can be rotated horizontally above the work set WS in the direction of the arrow shown around the rotation shaft 45 by a rotation mechanism (not shown). Here, in this embodiment, the first area S1 set by the area setting section 60 (see FIG. 3), specifically the area to be irradiated with ultraviolet light by the ultraviolet irradiation unit 42, is an annular area including the ring frame F of the work set WS, and the remaining circular area including the work W is a second area S2 to which ultraviolet light is not irradiated by the ultraviolet irradiation unit 42.

[0074] Therefore, in this embodiment, the ultraviolet irradiation unit 42 is provided with only three light-emitting diodes 44 that move within the first area S1 as the ultraviolet irradiation unit 42 rotates, while these light-emitting diodes 44 are lit, as the ultraviolet irradiation unit 42 rotates horizontally below the work set WS in the direction of the arrow in the drawing about the rotation axis 45, and ultraviolet light is irradiated only onto the portion of the dicing tape T on the work set WS that is included in the first area S1, thereby reducing the adhesive strength of the dicing tape T to the ring frame F. In contrast, ultraviolet light is not irradiated onto the second area S2 that includes the workpiece, so the adhesive strength of the dicing tape T to the workpiece W does not decrease but remains high.

[0075] In the third embodiment, as in the second embodiment, ultraviolet light may be irradiated onto the dicing tape T at the portion where the workpiece W is attached before cutting.

[0076] As described above, in this embodiment, ultraviolet light is irradiated from the ultraviolet irradiation unit 42 only in the first area S1 that does not include the workpiece W toward the adhesive portion of the dicing tape T to the ring frame F, and ultraviolet light is not irradiated in the second area S2 that does not include the workpiece W. Therefore, in addition to obtaining the same effect as in the second embodiment, the number of light-emitting diodes 44 can be reduced, thereby achieving the effect of making the ultraviolet irradiation unit 42 smaller, simplifying the structure, and reducing costs.

[0077] Although the above description has been given of an embodiment in which the present invention is applied to a cutting device that cuts a rectangular workpiece, the workpiece may be circular, such as a wafer.

[0078] Furthermore, the present invention can be similarly applied to any other processing device equipped with an ultraviolet irradiation device, such as a grinding device or a polishing device, in addition to a cutting device. For example, in a grinding device, in a processing method in which a cutting blade is used to first grind the back surface of a wafer with half-cut grooves formed on the front surface (device surface side) to expose the half-cut grooves on the grinding surface, the wafer is divided into chips, and the chips are picked up, if air enters due to unevenness on the device surface, the adhesive layer attached to the chip is not over-cured, thereby minimizing the difference in hardness between the hardened and unhardened portions of the adhesive layer, and preventing adhesive residue from remaining on the chip when it is picked up.

[0079] Furthermore, in the above embodiment, a configuration is adopted in which the ultraviolet irradiation unit 42 is moved relative to the holding table 10 (work set WS), but conversely, a configuration may be adopted in which the holding table 10 (work set WS) is moved relative to the ultraviolet irradiation unit 42.

[0080] Furthermore, the present invention is not limited to the application of the above-described embodiments, and it goes without saying that various modifications are possible within the scope of the claims and the technical ideas described in the specification and drawings. [Explanation of symbols]

[0081] 1: Cutting device (processing device), 2: Y-axis movement mechanism, 3: Slider, 4: Y-axis guide rail, 5: Y-axis ball screw, 6: Y-axis servo motor, 10: Holding table, 11: Clamp, 20: cutting mechanism, 21: first cutting unit, 22: second cutting unit, 23: Imaging unit, 24: Cutting blade, 30: Spinner cleaning mechanism, 31: spinner table, 40: ultraviolet irradiation device, 41: case, 41a: opening of case, 42: ultraviolet irradiation unit, 43: mounting rail, 44: Light-emitting diode (ultraviolet light-emitting part), 45: Rotation axis, 50: Y-axis movement mechanism, 51: guide rail, 52: ball screw, 53: servo motor, 53a: output shaft, 54: Encoder (position recognition unit), 55: Bearing, 56: Driven pulley, 57: Driving pulley, 58: timing belt, 59: nut member, 60: area setting unit, 70: control unit, 71: Frame guide, 72: First conveying mechanism, 73: Second conveying mechanism, 80: Z-axis moving mechanism, 81: Z-axis guide rail, 82: lifting plate, 83: Z-axis ball screw, 84: Z-axis servo motor, 90: loading / unloading mechanism, 91: guide rail, 92: arm, 94: Ball screw, 95: Servo motor, 96: Bearing, 100: Base, 101: Column, 110: support rod, C: tip, D: device, F: ring frame, L1, L2: planned division line, P: recess, S1: first area, S2: second area, W: Work, WS: Work set

Claims

1. a holding table that holds a work set that is an integrated unit formed by adhering a dicing tape to a ring frame and a work placed in an opening of the ring frame; a bar-shaped ultraviolet irradiation unit in which a plurality of ultraviolet light emitting units are arranged in a straight line parallel to the upper surface of the holding table; a moving mechanism that moves the ultraviolet irradiation unit and the holding table relatively in parallel with an upper surface of the holding table; An ultraviolet irradiation device comprising: an area setting unit that sets an area in which the adhesive strength of the dicing tape is reduced; a control unit that controls at least one of the ultraviolet irradiation unit and the moving mechanism so that the ultraviolet irradiation unit irradiates ultraviolet light toward the area set by the area setting unit; An ultraviolet irradiation device comprising:

2. The moving mechanism includes: a drive source that relatively moves the ultraviolet irradiation unit in a Y-axis direction that is perpendicular to the longitudinal direction of the ultraviolet irradiation unit; and a position recognition unit that recognizes the position of the ultraviolet irradiation unit in the Y-axis direction, The control unit controlling a moving speed of the ultraviolet irradiation unit in accordance with a position recognized by the position recognition unit of the ultraviolet irradiation unit, which continuously moves in a Y-axis direction corresponding to the area set by the setting unit; 2. The ultraviolet irradiation device according to claim 1.

3. The control unit controlling the power supplied to each of the plurality of ultraviolet light-emitting units in accordance with the position recognized by the position recognition unit of the ultraviolet light irradiation unit that continuously moves in the Y-axis direction corresponding to the area set by the area setting unit; 2. The ultraviolet irradiation device according to claim 1.

4. The moving mechanism includes: a rotation mechanism that rotates the ultraviolet irradiation unit relative to the holding table in a direction parallel to the upper surface of the holding table around one end side of the ultraviolet irradiation unit as an axis, the ultraviolet irradiation unit supplies power to the ultraviolet light emitting unit that moves within the area set by the area setting unit.

2. The ultraviolet irradiation device according to claim 1.

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