Inspection method and inspection apparatus

Abstract

To provide an inspection method capable of inspecting inexpensively and quickly whether an adhesive film is divided along each of a plurality of division scheduled lines or not together with a work-piece.SOLUTION: A backside of a work-piece is imaged in a state where light in a predetermined wavelength range is emitted toward the backside of the work-piece, where intensity of reflected light in the predetermined wavelength range is larger in an area where an adhesive film exists than in an area where the adhesive film does not exist. This enables inspection of whether the adhesive film is divided along each of the plurality of division scheduled lines or not to be accurately performed, by comparing the intensity of the light with a predetermined threshold. The backside of the work-piece can be imaged utilizing an inexpensive imaging unit and an inexpensive light source, so that the inspection can be executed at low cost. Further, areas corresponding to the plurality of division scheduled lines can be imaged collectively, which enables the inspection to be quickly executed.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to an inspection method for inspecting whether an adhesive film is divided along each of a plurality of planned division lines after a work piece whose back side is adhered to a tape via the adhesive film is divided along each of the plurality of planned division lines, and an inspection apparatus for carrying out this inspection method.

Background Art

[0002] Chips of devices such as ICs (Integrated Circuits) are indispensable components in various electronic devices such as mobile phones and personal computers. Such chips are manufactured, for example, by dividing a work piece such as a wafer having a plurality of devices formed on its front side along each of a plurality of planned division lines.

[0003] Also, when a chip is fixed to a predetermined structure (for example, another chip or a substrate), the adhesive film provided on the back surface of the work piece may be divided along each of the plurality of planned division lines together with the work piece (see, for example, Patent Document 1). Specifically, a tape is adhered to the back surface side of this work piece via an adhesive film, and the adhesive film is divided along each of the plurality of planned division lines together with the work piece by cutting a cutting blade into the tape from its front surface side.

[0004] Furthermore, after cutting the cutting blade into the work piece in this way, it is often inspected whether the work piece is divided along each of the plurality of planned division lines. This inspection is performed, for example, by determining whether the light leaks in a region corresponding to the plurality of planned division lines on the front surface side in a state where visible light is irradiated from the back surface side of the work piece (see, for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2000-182995 [Patent Document 2] Japanese Patent Publication No. 2005-251986 [Overview of the project] [Problems that the invention aims to solve]

[0006] The adhesive film on the back of the workpiece may be made of a semi-transparent material that allows some visible light to pass through. Therefore, in the inspection described above, it can be difficult to determine whether the adhesive film, along with the workpiece, is divided along each of the multiple planned division lines.

[0007] Furthermore, it is possible to use a line sensor capable of high-resolution imaging to determine whether the adhesive film, along with the workpiece, is divided along the planned division line. However, line sensors are expensive. Also, if areas corresponding to multiple planned division lines are imaged using the line sensor, the inspection time will be longer.

[0008] In view of these points, the object of the present invention is to provide an inspection method that can perform an accurate and rapid inspection of whether or not the adhesive film is divided together with the workpiece along each of a plurality of planned division lines, and an inspection apparatus capable of performing this inspection method. [Means for solving the problem]

[0009] According to one aspect of the present invention, an inspection method for checking whether an adhesive film has been divided along each of a plurality of planned division lines after dividing a workpiece, which has its back side attached to a tape via an adhesive film, the method being applied to the back side of the workpiece, with the adhesive film facing each of the plurality of planned division lines. Reflected by the adhesive film With light within a predetermined wavelength range irradiated, By utilizing light within a predetermined wavelength range in which the intensity is greater in the area where the adhesive film is present than in the area where it is not present.An inspection method is provided, comprising: an imaging step of imaging the back side of the workpiece; a determination step of determining whether the adhesive film is divided along each of the multiple division lines by comparing the intensity of light in a predetermined wavelength range in the region corresponding to the multiple division lines imaged in the imaging step with a predetermined threshold; and a notification step of notifying the user if the determination step determines that the adhesive film is not divided along any of the multiple division lines.

[0010] According to another aspect of the present invention, an inspection device for inspecting whether an adhesive film has been divided along each of a plurality of planned division lines after dividing a workpiece, which has its back side attached to a tape via an adhesive film, along each of a plurality of planned division lines, wherein the inspection device is directed toward the back side of the workpiece. Reflected by the adhesive film The system comprises a light source that emits light in a predetermined wavelength range, an imaging unit that images the back side of the workpiece, a notification unit that notifies that the adhesive film is not divided along any of the plurality of division lines, and a control unit that controls the light source, the imaging unit, and the notification unit, wherein the control unit stores a threshold value used to determine whether or not the adhesive film is divided along each of the plurality of division lines, and controls the light source to emit light in the predetermined wavelength range toward the back side of the workpiece. By utilizing light within a predetermined wavelength range in which the intensity is greater in the area where the adhesive film is present than in the area where it is not present. An inspection apparatus is provided, comprising: an imaging unit that controls an imaging unit to image the back side of the workpiece; a determination unit that determines whether the adhesive film is divided along each of the multiple division lines by comparing the intensity of light in a predetermined wavelength range in a region corresponding to the multiple division lines imaged by the imaging unit with a threshold; and a notification unit that controls a notification unit to notify the determination unit if it determines that the adhesive film is not divided along any of the multiple division lines. [Effects of the Invention]

[0011] In this invention, the back side of a workpiece is imaged while irradiating it with light in a predetermined wavelength range. In this case, the intensity of the reflected light in the predetermined wavelength range is greater in areas where the adhesive film is present than in areas where it is not. Therefore, by comparing this light intensity with a predetermined threshold, it is possible to accurately inspect whether or not the adhesive film is divided along each of the multiple planned division lines.

[0012] Furthermore, since this imaging can be performed using an inexpensive imaging unit and light source, this inspection can be carried out at a low cost in the present invention. In addition, since this imaging can be performed simultaneously on areas corresponding to multiple planned division lines, this inspection can be carried out quickly in the present invention. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a schematic perspective view showing a frame unit including a workpiece. [Figure 2] Figure 2 is a flowchart illustrating a schematic example of a chip manufacturing method, in which chips are produced from a workpiece. [Figure 3] Figure 3 is a schematic perspective view showing an example of a cutting machine with an inspection function. [Figure 4] Figure 4 is a schematic side view showing some of the components of the cutting device. [Figure 5] Figure 5 is a partial cross-sectional side view showing an enlarged view of some of the components of the cutting device. [Figure 6] Figure 6 is a schematic functional block diagram showing an example of a control unit for a cutting machine. [Figure 7] Figure 7 is a flowchart that schematically shows an example of the inspection steps shown in Figure 2. [Figure 8] Figure 8 is a flowchart that schematically shows an example of the division steps shown in Figure 2. [Figure 9] Figure 9 is a schematic perspective view showing an example of a laser processing apparatus. [Figure 10] FIG. 10 is a diagram schematically showing the state in which a laser beam travels inside a laser processing apparatus. [Figure 11] FIG. 11 is a partial cross-sectional side view schematically showing an example of an extended apparatus with an inspection function.

Embodiments for Carrying out the Invention

[0014] Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view schematically showing a frame unit including a workpiece. The frame unit 1 shown in FIG. 1 includes a disk-shaped workpiece 11 having generally parallel surfaces 11a and a back surface 11b.

[0015] This workpiece 11 is, for example, a wafer made of a semiconductor material such as silicon (Si). Further, the workpiece 11 is partitioned into a plurality of regions by a plurality of division planned lines 13a extending parallel to each other and a plurality of division planned lines 13b extending parallel to each other and orthogonal to the plurality of division planned lines 13a. And devices 15 such as ICs are formed on the surface 11a side of each of the plurality of regions.

[0016] Note that there are no restrictions on the material, shape, structure, size, etc. of the workpiece 11. For example, the workpiece 11 may be made of other semiconductors, ceramics, resins, metals, or the like. Further, the workpiece 11 may be a rectangular package substrate. Similarly, there are no restrictions on the type, quantity, shape, structure, size, arrangement, etc. of the device 15.

[0017] Also, a disk-shaped adhesive film 17 having a diameter larger than that of the workpiece 11 is provided on the back surface 11b of the workpiece 11. This adhesive film 17 is generally a film-shaped adhesive called a die attach film (DAF), and is used when fixing chips obtained by dividing the workpiece 11 to a predetermined structure.

[0018] The adhesive film 17 is made of a thermosetting or UV-curing resin, for example, that reflects light in a predetermined wavelength range of visible light (e.g., red light with wavelengths of 610 nm to 750 nm and blue light with wavelengths of 435 nm to 480 nm, etc.) and transmits light in other wavelength ranges (e.g., green light with wavelengths of 500 nm to 560 nm, etc.). Specifically, the adhesive film 17 is made of an epoxy resin, etc.

[0019] Furthermore, a disc-shaped tape 19 with a larger diameter than the adhesive film 17 is attached to the back surface 11b of the workpiece 11 via the adhesive film 17. This tape 19 has, for example, a flexible film-like base layer and an adhesive layer (glue layer) provided on one side of the base layer (the side facing the adhesive film 17).

[0020] The base layer and adhesive layer are made of a resin or the like that transmits visible light. Specifically, the base layer is made of polyolefin (PO), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), or polystyrene (PS). The adhesive layer is made of UV-curable silicone rubber, acrylic material, or epoxy material.

[0021] Furthermore, an annular frame 21 is attached to the outer periphery of the tape 19, with a circular opening having a larger diameter than the workpiece 11. This frame 21 is made of a metal material such as aluminum.

[0022] Figure 2 is a schematic flowchart illustrating an example of a chip manufacturing method for producing chips from a workpiece 11 contained in a frame unit 1. In this method, first, the workpiece 11 is divided along each of the multiple division lines 13a and 13b (division step: S1). Then, it is checked whether the adhesive film 17 is divided along each of the multiple division lines 13a and 13b (inspection step: S2).

[0023] Figure 3 is a schematic perspective view showing an example of a cutting machine with an inspection function capable of performing a splitting step (S1) and an inspection step (S2). Note that the X-axis and Y-axis directions shown in Figure 3 are mutually orthogonal directions on the horizontal plane, and the Z-axis direction is perpendicular to the X-axis and Y-axis directions (vertical direction).

[0024] The cutting apparatus 2 shown in Figure 3 has a base 4 that supports each component. A pair of guide rails 6, each extending along the Y-axis, are provided on the upper surface of the base 4. A rectangular parallelepiped-shaped movable plate 8, extending along the X-axis, is slidably connected to the upper surface of the pair of guide rails 6.

[0025] Furthermore, a screw shaft 10 extending along the Y-axis direction is positioned between the pair of guide rails 6. A motor 12 for rotating the screw shaft 10 is connected to one end of this screw shaft 10. A nut (not shown) for housing balls that roll on the surface of the rotating screw shaft 10 is provided on the surface of the screw shaft 10, where a helical groove is formed, thus forming a ball screw.

[0026] In other words, as the screw shaft 10 rotates, the balls circulate within the nut, causing the nut to move along the Y-axis. This nut is fixed to the underside of the movable plate 8. Therefore, when the motor 12 rotates the screw shaft 10, the movable plate 8 moves along the Y-axis along with the nut.

[0027] Furthermore, a Y-axis scale 14 is provided in the area adjacent to the guide rail 6 on the upper surface of the base 4. This Y-axis scale 14 is used to measure the position of the movable plate 8 in the Y-axis direction.

[0028] Furthermore, a pair of guide rails 16, each extending along the X-axis, are provided on the upper surface of the movable plate 8. The table base 18 is slidably connected to the upper side of the pair of guide rails 16. The detailed structure of the table base 18 will be described later.

[0029] Furthermore, a screw shaft 20 extending along the X-axis direction is positioned between the pair of guide rails 16. A motor 22 for rotating the screw shaft 20 is connected to the front end (one end) of this screw shaft 20. A nut (not shown) for housing a ball that rolls on the surface of the rotating screw shaft 20 is provided on the surface of the screw shaft 20, where a helical groove is formed, thus forming a ball screw.

[0030] In other words, as the screw shaft 20 rotates, the balls circulate within the nut, causing the nut to move along the X-axis. This nut is fixed to the underside of the table base 18. Therefore, when the motor 22 rotates the screw shaft 20, the table base 18 moves along the X-axis along with the nut.

[0031] Furthermore, an X-axis scale 24 is provided in the area adjacent to the guide rail 16 on the upper surface of the movable plate 8. This X-axis scale 24 is used to measure the position of the table base 18 in the X-axis direction.

[0032] Furthermore, a holding table 26 is provided on the upper surface of the table base 18, and a motor 28 is provided on its side for rotating the holding table 26, with the rotation axis being a straight line that passes through the center of the holding table 26 and is aligned with the Z-axis direction.

[0033] Figure 4 is a schematic side view showing the table base 18, the holding table 26, and the motor 28. The table base 18 has a rectangular parallelepiped bottom plate portion 18a. The lower part of this bottom plate portion 18a is connected to a pair of guide rails 16. In addition, a rectangular parallelepiped upright portion 18b extending upward is provided at the upper part of the front end of the bottom plate portion 18a.

[0034] Furthermore, a rectangular parallelepiped top plate portion 18c extending to the rear is provided at the rear of the upper end of the upright portion 18b. A cylindrical through hole (not shown) is formed in the center of this top plate portion 18c, penetrating the top plate portion 18c in the vertical direction. In addition, in the table base 18, an open space 18d exists between the upper surface of the bottom plate portion 18a and the lower surface of the top plate portion 18c.

[0035] Furthermore, a holding table 26 is provided on the upper surface of the top plate portion 18c so as to cover the through hole formed in the top plate portion 18c. This holding table 26 is supported by the table base 18 in such a manner that it can rotate around a straight line passing through the center of the holding table 26 and along the Z-axis direction as its axis of rotation.

[0036] Figure 5 is a partially cross-sectional side view showing an enlarged portion of the table base 18 and the holding table 26. As shown in Figure 5, the holding table 26 has a disc-shaped holding member 26a located above the top plate portion 18c. This holding member 26a is made of a material that transmits visible light, such as soda glass, borosilicate glass, or quartz glass.

[0037] Furthermore, a cylindrical fitting portion 26b is provided on the lower side of the outer circumference of the retaining member 26a. A suction passage 26c is formed inside the retaining member 26a and the fitting portion 26b, and this suction passage 26c is connected to a suction source (not shown), such as an ejector, via a pipe 30 or the like that is connected to the outer surface of the fitting portion 26b.

[0038] Furthermore, an annular fitting hole is formed in the top plate portion 18c so as to surround the through hole, and the lower part of the fitting portion 26b is inserted into this fitting hole in a manner that allows it to slide. In addition, a cylindrical driven pulley 32 is provided on the outer surface of the fitting portion 26b, and a belt 34 is placed over this driven pulley 32.

[0039] As shown in Figure 4, this belt 34 is also placed over the upper part of the drive pulley 36, which extends along the Z-axis direction. The lower part of this drive pulley 36 is connected to a motor 28 located on the front of the upright section 18b.

[0040] Therefore, when the motor 28 operates, the driving pulley 36 rotates with a straight line along the Z-axis as its axis of rotation. The force that rotates the driving pulley 36 is also transmitted to the driven pulley 32 via the belt 34. As a result, together with the driven pulley 32, the holding table 26 rotates with a straight line passing through its center and along the Z-axis as its axis of rotation.

[0041] Furthermore, cylindrical frame support parts 38 are provided at each of the four corners of the upper surface of the table base 18 (the upper surface of the tabletop portion 18c). These frame support parts 38 support the frame 21 via the tape 19 when the frame unit 1 is placed on the holding table 26.

[0042] Furthermore, the upper surface of the frame support portion 38 is set lower than the upper surface of the holding table 26 so that when the frame unit 1 is placed on the holding table 26, the upper surface of the frame 21 is positioned lower than the upper surface of the holding table 26 (the upper surface of the holding member 26a).

[0043] Then, with the frame unit 1 placed on the holding table 26, when the suction source, which communicates with the suction passage 26c formed inside the holding member 26a and fitting portion 26b of the holding table 26, is activated, the workpiece 11 is attracted to and held by the holding table 26 via the adhesive film 17 and tape 19.

[0044] Referring again to Figure 3, the remaining components of the cutting apparatus 2 will be described. Behind the holding table 26 and the like, a rectangular parallelepiped support structure 40 is provided. On the sides of this support structure 40, there is a pair of guide rails 42, each extending along the Z-axis direction.

[0045] A rectangular parallelepiped spindle housing 44, extending along the X-axis, is slidably connected to the surface side of the pair of guide rails 42. A screw shaft 46, extending along the Z-axis, is positioned between the pair of guide rails 42.

[0046] A motor 48 for rotating the screw shaft 46 is connected to the upper end (one end) of the screw shaft 46. A nut (not shown) for housing a ball that rolls on the surface of the rotating screw shaft 46 is provided on the surface of the screw shaft 46 where a helical groove is formed, thus forming a ball screw.

[0047] In other words, as the screw shaft 46 rotates, the balls circulate within the nut, causing the nut to move along the Z-axis direction. This nut is fixed to the side of the spindle housing 44 facing the support structure 40. Therefore, when the motor 48 rotates the screw shaft 46, the spindle housing 44 moves along the Z-axis direction along with the nut.

[0048] The spindle housing 44 houses a spindle (not shown) that extends along the X-axis direction, and a motor (not shown) connected to the base end (rear end) of the spindle, which rotates the spindle with a straight line along the X-axis direction as its axis of rotation. The tip (front end) of the spindle is exposed through an opening formed on the front surface of the spindle housing 44.

[0049] Furthermore, an annular cutting blade 50 is attached to the tip of the spindle exposed from the spindle housing 44. Therefore, when the spindle rotates, the cutting blade 50 rotates together with the spindle, with the axis of rotation being a straight line along the X-axis. In addition, an upper imaging unit 52 is provided on the side of the spindle housing 44 that is farther from the support structure 40.

[0050] The upper imaging unit 52 uses visible light to image structures located below it. A lower imaging unit 54 is positioned opposite the upper imaging unit 52 in the vertical direction. This lower imaging unit 54 uses visible light to image structures located above it.

[0051] Specifically, each of the upper imaging unit 52 and the lower imaging unit 54 includes, for example, an objective lens and an image sensor such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor.

[0052] Furthermore, one end of a connecting portion 56 extending along the X-axis is connected to the lower imaging unit 54. A light source 58 is provided on the upper surface of the connecting portion 56. When the lower imaging unit 54 images a structure located above the lower imaging unit 54, the light source 58 irradiates the structure with light within a predetermined wavelength range of visible light (for example, red light and blue light).

[0053] Furthermore, the upper part of the lifting support mechanism 60 is connected to the other end of the connecting part 56. The lower part of this lifting support mechanism 60 is fixed to the upper surface of the base 4 and supports the lower imaging unit 54, the connecting part 56, and the light source 58 so that they can move up and down.

[0054] Furthermore, a cover (not shown) is provided on the upper surface of the base 4 to cover the aforementioned components. A touch panel 62 is positioned on the front of this cover. This touch panel 62 is composed of, for example, an input unit such as a capacitive or resistive touch sensor and a display unit (notification unit) such as a liquid crystal display or an organic EL (Electro-Luminescence) display, and functions as a user interface.

[0055] Furthermore, the cutting device 2 incorporates a control unit that controls the components described above. Figure 6 is a schematic functional block diagram showing an example of the control unit of the cutting device 2. The control unit 64 shown in Figure 6 has a processing unit 66 and a storage unit 68.

[0056] The processing unit 66 is composed of a processor, such as a CPU (Central Processing Unit). The storage unit 68 is composed of volatile memory, such as DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory), and non-volatile memory, such as an SSD (Solid State Drive) (NAND flash memory) or an HDD (Hard Disk Drive) (magnetic storage device).

[0057] The memory unit 68 stores various types of information (data and programs, etc.) used in the processing unit 66. For example, the memory unit 68 stores threshold values ​​for the intensity of light within a predetermined wavelength range (e.g., red light and blue light). These threshold values ​​are used to determine whether or not the adhesive film 17 is divided. An example of this determination will be described later.

[0058] Furthermore, the processing unit 66 reads and executes various programs stored in the storage unit 68 to control the components of the cutting device 2. This processing unit 66 includes, for example, a drive unit 70, an imaging unit 72, a determination unit 74, and a notification unit 76.

[0059] The drive unit 70 controls the movement or rotation of the components of the cutting device 2. For example, the drive unit 70 controls the motors 12, 22 and / or the lifting support mechanism 60 so that the holding table 26 is positioned between the upper imaging unit 52 and the lower imaging unit 54.

[0060] The imaging unit 72 controls the upper imaging unit 52, the lower imaging unit 54, and the light source 58. For example, the imaging unit 72 controls the light source 58 so that light in a predetermined wavelength range is irradiated toward the back surface 11b of the workpiece 11 held by the holding table 26, and controls the lower imaging unit 54 to image the back surface 11b of the workpiece 11.

[0061] The determination unit 74 determines whether the adhesive film 17 is divided along each of the multiple division lines 13a and 13b. This determination is made, for example, by comparing the intensity of light in a predetermined wavelength range in the region corresponding to the multiple division lines 13a and 13b captured by the lower imaging unit 54 with a threshold value stored in the storage unit 68.

[0062] The notification unit 76 controls the display unit of the touch panel 62. For example, if the determination unit 74 determines that the adhesive film 17 has not been divided along any of the multiple division lines 13a, 13b, the notification unit 76 controls the display unit to notify the user of that fact.

[0063] In the cutting apparatus 2, for example, the splitting step (S1) and the inspection step (S2) are performed in the following order. Specifically, first, the frame unit 1 is placed on the holding table 26 so that the surface 11a of the workpiece 11 faces upward. That is, the workpiece 11 is placed on the holding member 26a via the adhesive film 17 and tape 19, and the frame 21 is placed on the frame support part 38 via the tape 19.

[0064] Next, a suction source is activated, which communicates with a suction passage 26c formed inside the holding member 26a and fitting portion 26b of the holding table 26 via the piping 30. As a result, the workpiece 11 is attracted to and held by the holding table 26 via the adhesive film 17 and tape 19.

[0065] Next, the drive unit 70 controls the motors 12 and 22 to move the moving plate 8 and the table base 18 so that the holding table 26 is positioned between the upper imaging unit 52 and the lower imaging unit 54. That is, the lower imaging unit 54 is positioned in the open space 18d between the bottom plate portion 18a and the top plate portion 18c of the table base 18.

[0066] Next, the imaging unit 72 controls the upper imaging unit 52 to image the surface 11a side of the workpiece 11. Then, referring to the image formed by the imaging by the upper imaging unit 52, the drive unit 70 controls the motor 28 to rotate the holding table 26 so that the multiple division lines 13a or multiple division lines 13b are parallel to the Y-axis direction.

[0067] Next, the drive unit 70 controls the motors 12 and 22 to move the moving plate 8 and the table base 18 so that, in a plan view, the cutting blade 50 is positioned in the Y-axis direction with respect to one of the multiple division lines 13a or multiple division lines 13b that are parallel to the Y-axis direction. Then, the drive unit 70 controls the motor 48 to move the spindle housing 44 so that the lower end of the cutting blade 50 is positioned higher than the lower surface of the tape 19 and lower than the upper surface of the tape 19.

[0068] Next, the drive unit 70 controls the motor housed in the spindle housing 44 to rotate the cutting blade 50. Then, while the cutting blade 50 is still rotating, the drive unit 70 controls the motor 12 to move the moving plate 8 so that the workpiece 11 passes over the cutting blade 50 from one end to the other in the Y-axis direction.

[0069] This divides the workpiece 11 along either one of the multiple division lines 13a or one of the multiple division lines 13b. Furthermore, by repeating the same operation, the cutting blade 50 is divided into the workpiece 11 along each of the multiple division lines 13a and 13b. This completes the division step (S1).

[0070] Once the splitting step (S1) is complete, the drive unit 70 controls the motors 12 and 22 to move the moving plate 8 and the table base 18 so that the holding table 26 is positioned between the upper imaging unit 52 and the lower imaging unit 54. Then, the inspection step (S2) shown in Figure 2 is performed.

[0071] Figure 7 is a flowchart schematically showing an example of the inspection step (S2). In the inspection step (S2) shown in Figure 7, first, the back surface 11b of the workpiece 11 is imaged while irradiating it with light in a predetermined wavelength range (imaging step: S21).

[0072] Specifically, the imaging unit 72 controls the light source 58 so that light within a predetermined wavelength range is irradiated toward the back surface 11b of the workpiece 11, and then controls the lower imaging unit 54 to image this back surface 11b. At this time, the light intensity of the region where the adhesive film 17 is divided among the regions corresponding to the multiple division lines 13a and 13b becomes greater than the light intensity of the region where it is not divided.

[0073] Next, the intensity of light in a predetermined wavelength range in the regions corresponding to the multiple planned division lines 13a and 13b that were captured is compared with a threshold (determination step: S22). Specifically, the determination unit 74 compares the intensity of light in each region with the threshold stored in the memory unit 68. If the intensity of light in each region is less than the threshold (step (S23): YES), the inspection step (S2) is terminated.

[0074] On the other hand, if the light intensity in any of the regions corresponding to the multiple planned division lines 13a and 13b that have been imaged is greater than a threshold (step (S23): NO), the system notifies that the adhesive film 17 has not been divided in the region where the light intensity is greater than the threshold (notification step: S24). Specifically, the notification unit 76 controls the display unit of the touch panel 62 to notify the system of this fact.

[0075] For example, the notification unit 76 displays a figure corresponding to the workpiece 11 and controls the display unit to highlight the areas where the adhesive film 17 has not been divided among the areas corresponding to the multiple division lines 13a and 13b included in this figure. This allows the operator of the cutting device 2 to understand which division lines 13a and 13b require the division step (S1) to be performed again.

[0076] In the method shown in Figure 2, the back surface 11b of the workpiece 11 is imaged while irradiating it with light in a predetermined wavelength range toward the back surface 11b of the workpiece 11. In this case, the intensity of the reflected light in the predetermined wavelength range is greater in the areas where the adhesive film 17 is present than in the areas where it is not present. Therefore, by comparing this light intensity with a predetermined threshold, it is possible to accurately inspect whether or not the adhesive film 17 is divided along each of the multiple planned division lines 13a and 13b.

[0077] Furthermore, since this imaging can be performed using an inexpensive lower imaging unit 54 and light source 58, this method allows for inexpensive inspection. In addition, since this imaging can be performed simultaneously on areas corresponding to multiple planned division lines 13a and 13b, this method allows for rapid inspection.

[0078] It should be noted that the above description represents only one aspect of the present invention, and the present invention is not limited to the above description. For example, in the present invention, the light irradiated when imaging the back surface 11b of the workpiece 11 is not limited to visible light. That is, this light may be white light including all of red, green, and blue light, or infrared light, as long as it is light of a wavelength that passes through the tape 19 and is reflected by the adhesive film 17.

[0079] Furthermore, in the present invention, the notification unit 76 may also control the display unit of the touch panel 62 to notify the user if the light intensity of any of the regions corresponding to the multiple planned division lines 13a and 13b captured in the imaging step (S21) is less than a threshold (step (S23): YES).

[0080] Furthermore, in the present invention, another input unit and / or notification unit may be provided in place of or in addition to the touch panel 62. Examples of the other input unit include a keyboard, mouse, touchpad, or microphone. Examples of the other notification unit include a printer, speaker, or warning light (pilot lamp).

[0081] Furthermore, in the present invention, the splitting step (S1) and the inspection step (S2) may be performed in separate devices. That is, in the present invention, the splitting step (S1) may be performed in a splitting device specialized for splitting the workpiece 11, and then the inspection step (S2) may be performed in an inspection device specialized for inspecting the workpiece 11.

[0082] Furthermore, in the present invention, the workpiece 11 may be divided using a laser beam. Figure 8 is a flowchart schematically showing an example of such a division step (S1). In this division step (S1), first, a laser beam is irradiated onto the workpiece 11 along each of the multiple division lines 13a, 13b to form a modified layer inside the workpiece 11 (modified layer formation step: S11).

[0083] Next, the tape 19 attached to the workpiece 11 is expanded (expansion step: S12). This causes an external force to act on the workpiece 11. As a result, the modified layer becomes the dividing point and the workpiece 11 is divided. That is, the workpiece 11 is divided along multiple planned dividing lines 13a, 13b.

[0084] Furthermore, in the present invention, the expansion step (S12) and the inspection step (S2) shown in Figure 2 may be performed in the same apparatus. Below, an example of a chip manufacturing method including a modified layer formation step (S11) performed in a laser processing apparatus and an expansion step (S12) and an inspection step (S2) performed in an expansion apparatus with an inspection function will be described in detail.

[0085] Figure 9 is a schematic perspective view showing an example of a laser processing apparatus capable of performing the modified layer formation step (S11). Note that the U-axis and V-axis directions shown in Figure 9 are mutually orthogonal directions on the horizontal plane, and the W-axis direction is perpendicular to the U-axis and V-axis directions (vertical direction).

[0086] The laser processing apparatus 78 shown in Figure 9 has a base 80 that supports each component. A pair of guide rails 82, each extending along the V-axis direction, are provided on the upper surface of this base 80. A rectangular parallelepiped movable plate 84, extending along the U-axis direction, is slidably connected to the upper surface of the pair of guide rails 82.

[0087] Furthermore, a screw shaft 86 extending along the V-axis direction is positioned between the pair of guide rails 82. A motor 88 for rotating the screw shaft 86 is connected to one end of this screw shaft 86. A nut (not shown) for housing balls that roll on the surface of the rotating screw shaft 86 is provided on the surface of the screw shaft 86, where a helical groove is formed, thus forming a ball screw.

[0088] In other words, as the screw shaft 86 rotates, the balls circulate within the nut, causing the nut to move along the V-axis direction. This nut is fixed to the underside of the movable plate 84. Therefore, when the motor 88 rotates the screw shaft 86, the movable plate 84 moves along the V-axis direction along with the nut.

[0089] Furthermore, a pair of guide rails 90, each extending along the U-axis direction, are provided on the upper surface of the movable plate 84. The movable plate 92 is connected to the upper side of the pair of guide rails 90 in a manner that allows it to slide.

[0090] Furthermore, a screw shaft 94 extending along the U-axis direction is positioned between the pair of guide rails 90. A motor 96 for rotating the screw shaft 94 is connected to one end of this screw shaft 94. A nut (not shown) for housing balls that roll on the surface of the rotating screw shaft 94 is provided on the surface of the screw shaft 94, where a helical groove is formed, thus forming a ball screw.

[0091] In other words, as the screw shaft 94 rotates, the balls circulate within the nut, causing the nut to move along the U-axis direction. This nut is fixed to the underside of the movable plate 92. Therefore, when the motor 96 rotates the screw shaft 94, the movable plate 92 moves along the U-axis direction along with the nut.

[0092] Furthermore, a cylindrical table base 98 and a holding table 100 mounted on the table base 98 are provided on the upper side of the movable plate 92. The holding table 100 has a disc-shaped frame 102 made of ceramics or the like. The frame 102 has a disc-shaped bottom wall and cylindrical side walls that rise from the outer edge of the bottom wall.

[0093] Specifically, a disc-shaped recess is formed on the upper surface of the frame 102, defined by the bottom wall and side walls. A disc-shaped porous plate 104, having a diameter approximately equal to the diameter of the recess, is fixed to the recess formed on the upper surface of the frame 102. This porous plate 104 is made of, for example, porous ceramics.

[0094] Furthermore, multiple clamps 106 are provided around the holding table 100 at approximately equal angular intervals along the circumferential direction of the holding table 100. When the frame unit 1 is brought into the laser processing machine 78, the workpiece 11 is placed on the holding table 100 via the adhesive film 17 and tape 19, and the frame 21 is gripped by the multiple clamps 106 with the upper surface of the frame 21 positioned lower than the upper surface of the holding table 100.

[0095] Furthermore, the holding table 100 and the multiple clamps 106 are connected to a rotational drive source (not shown), such as a motor. When this rotational drive source operates, the holding table 100 and the multiple clamps 106 rotate around a straight line along the Z-axis as the axis of rotation.

[0096] Furthermore, the porous plate 104 of the holding table 100 communicates with a suction source (not shown), such as an ejector, through a through hole formed in the bottom wall of the frame 102. When the frame unit 1 is loaded into the laser processing device 78 and the suction source is activated, a suction force acts on the workpiece 11 via the adhesive film 17 and tape 19, and the workpiece 11 is held in place by the holding table 100.

[0097] Furthermore, a support structure 108 is provided on the base 80. A pair of guide rails 110, each extending along the W-axis direction, are provided on the side of this support structure 108. A rectangular parallelepiped movable plate 112 is slidably connected to the side of the pair of guide rails 110 that is furthest from the support structure 108.

[0098] Furthermore, a screw shaft (not shown) extending along the W-axis direction is positioned between the pair of guide rails 110. A motor 114 for rotating the screw shaft is connected to one end (upper end) of this screw shaft. A nut (not shown) for housing balls that roll on the surface of the rotating screw shaft is provided on the surface of the screw shaft where a helical groove is formed, thus forming a ball screw.

[0099] In other words, as the screw shaft rotates, the balls circulate within the nut, causing the nut to move along the W-axis direction. This nut is fixed to the side of the movable plate 112 closest to the support structure 108. Therefore, when the screw shaft is rotated by the motor 114, the movable plate 112 moves along the W-axis direction together with the nut.

[0100] Furthermore, a support 116 is fixed to the side of the movable plate 112 that is far from the support structure 108. This support 116 supports a part of the laser beam irradiation unit 118. Figure 10 is a schematic diagram showing how the laser beam travels inside the laser processing apparatus 78. In Figure 10, some of the components of the laser beam irradiation unit 118 are shown as functional blocks.

[0101] As shown in Figures 9 and 10, the laser beam irradiation unit 118 includes, for example, a laser oscillator 120 fixed to a base 80, a cylindrical housing 122 with one end supported by a support 116 and extending along the V-axis direction, and an irradiation head 124 provided at the other end of the housing 122.

[0102] The laser oscillator 120 has a laser medium suitable for laser oscillation, such as Nd:YAG, and generates a laser beam LB with a wavelength that penetrates the workpiece 11 (e.g., 1064 nm) and irradiates the housing 122 side with it. The laser oscillation performed by the laser oscillator 120 may be either continuous wave oscillation or pulsed oscillation.

[0103] Furthermore, the housing 122 accommodates a part of the optical system that constitutes the laser beam irradiation unit 118, for example, the mirrors 122a and 122b shown in Figure 10, and guides the laser beam LB irradiated from the laser oscillator 120 to the irradiation head 124.

[0104] The irradiation head 124 houses another part of the optical system that constitutes the laser beam irradiation unit 118, such as a mirror 124a and a focusing lens 124b. The laser beam LB guided from the housing 122 has its path changed downward by the mirror 124a and is focused to a predetermined height on the side of the holding table 100 by the focusing lens 124b.

[0105] Furthermore, as shown in Figure 9, an imaging unit 126 is provided on the side of the housing 122 adjacent to the illumination head 124. This imaging unit 126 includes, for example, an objective lens and an image sensor such as a CCD image sensor or a CMOS image sensor, and uses visible light to image structures located below it.

[0106] In the laser processing apparatus 78, the modified layer formation step (S11) is carried out in the following order, for example. Specifically, first, the frame unit 1 is brought into the laser processing apparatus 78 so that the surface 11a of the workpiece 11 faces upward. That is, it is placed on the holding table 100 via the adhesive film 17 and tape 19, and the frame 21 is gripped by a plurality of clamps 106.

[0107] Next, a suction source communicating with the porous plate 104 through a through-hole formed in the bottom wall of the frame 102 is activated. This causes a suction force to act on the workpiece 11 via the adhesive film 17 and tape 19, and the workpiece 11 is held in place by the holding table 26.

[0108] Next, the motors 88 and 96 are controlled to move the moving plates 84 and 92 so that the holding table 100 is positioned directly below the imaging unit 126. Then, the imaging unit 126 images the surface 11a of the workpiece 11. Next, the holding table 100 is rotated by referring to the image formed by the imaging unit 126 so that the multiple division lines 13a or multiple division lines 13b are parallel to the U-axis direction.

[0109] Next, in a plan view, the motors 12 and 22 are controlled to move the moving plates 84 and 92 so that one of the multiple planned division lines 13a and 13b is positioned in the U-axis direction as seen from the irradiation head 124. Then, the motor 114 is controlled to move the moving plate 112 so that the focal point of the laser beam LB irradiated from the irradiation head 124 is positioned at a height corresponding to the inside of the workpiece 11.

[0110] Next, with the laser beam LB irradiated from the irradiation head 124, the motor 96 is controlled to move the moving plate 92 so that the focal point of the laser beam LB passes from one end to the other in the U-axis direction of the workpiece 11.

[0111] This creates a modified layer inside the workpiece 11 that extends along one of the multiple planned division lines 13a, 13. Furthermore, by repeating the same operation, a modified layer is created inside the workpiece 11 that extends along each of the multiple planned division lines 13a, 13b.

[0112] Figure 11 is a schematic partial cross-sectional side view showing an example of an expansion device with an inspection function capable of performing the expansion step (S12) and the inspection step (S2). The expansion device 128 shown in Figure 11 has a cylindrical drum 130. Inside this drum 130, there is an imaging unit 132 similar to the lower imaging unit 54 shown in Figure 3, and a light source 134 similar to the light source 58 shown in Figure 3.

[0113] Furthermore, a support unit 136 is provided around the drum 130. This support unit 136 has an annular support base 136a that surrounds the upper end of the drum 130. In addition, a plurality of gripping portions 136b are provided on the upper surface of the support base 136a at intervals of approximately equal angles along the circumferential direction of the support base 136a.

[0114] When the frame unit 1 is loaded into the expansion device 128, the frame 21 is placed on the support base 136a via the tape 19, and the frame 21 is gripped by the support base 136a and the multiple gripping parts 136b. In addition, multiple rods 136c are provided on the underside of the support base 136a at intervals of approximately equal angles along the circumferential direction of the support base 136a.

[0115] Each of the multiple rods 136c is, for example, a rod of an air cylinder and is movable up and down. When the multiple rods 136c move up and down, the support base 136a and the multiple gripping parts 136b also move up and down together with the multiple rods 136c.

[0116] Furthermore, the expansion device 128 is equipped with a touch panel (not shown) similar to the touch panel 62 shown in Figure 3. The expansion device 128 also has a control unit (not shown) similar to the control unit 64 shown in Figure 6.

[0117] In the expansion device 128, for example, the expansion step (S12) and the inspection step (S2) are performed in the following order. Specifically, first, the drive unit raises and lowers a plurality of rods 136c so that the upper surface of the support base 136a is positioned on the same plane as the upper end of the drum 130.

[0118] Next, the frame unit 1 is brought into the expansion device 128 so that the surface 11a of the workpiece 11 faces upward, and the frame 21 is gripped by the support base 136a and the multiple gripping parts 136b. Then, the drive unit lowers the support base 136a and the multiple gripping parts 136b together with the multiple rods 136c.

[0119] As a result, the tape 19 expands by the amount of the separation between the upper end of the drum 130 and the support base 136a. At this time, an external force acts on the adhesive film 17 and the workpiece 11, causing them to expand. Consequently, the modified layer formed inside the workpiece 11 along each of the multiple planned division lines 13a and 13b becomes the dividing point, and the workpiece 11 is divided.

[0120] Furthermore, when the workpiece 11 is divided in this way, strong local external forces act on the adhesive film 17 exposed along each of the multiple division lines 13a and 13b. As a result, the adhesive film 17 also becomes easier to divide along each of the multiple division lines 13a and 13b. With this, the expansion step (S12) is completed.

[0121] Then, once the expansion step (S12) is completed, the inspection step (S2) is performed as shown in Figure 7. Note that the inspection step (S2) performed in the expansion device 128 is the same as the inspection step (S2) performed in the cutting device 2, so refer to the above explanation for details.

[0122] As a result, the touch panel of the expansion device 128 can display, for example, that the adhesive film 17 has not been divided along any of the multiple planned division lines 13a, 13b. In this case, the operator can be prompted to perform the expansion step (S12) again.

[0123] Furthermore, the structures and methods of the embodiments described above can be modified as appropriate without departing from the scope of the present invention. [Explanation of Symbols]

[0124] 1: Frame Unit 2:Cutting device 4: Base 6: Guide rail 8: Mobile Plate 10: Screw shaft 11: Workpiece (11a: Front side, 11b: Back side) 12: Motor 13a, 13b: Planned division lines 14: Y-axis scale 15: Device 16: Guide rail 17: Adhesive film 18: Table base (18a: bottom plate, 18b: upright) (18c: Top panel, 18d: Open space) 19: Tape 20: Screw shaft 21: Frame 22: Motor 24: X-axis scale 26: Holding table (26a: Holding member, 26b: Fitting part, 26c: Suction passage) 28: Motor 30: Piping 32: Driven pulley 34: Belt 36: Driving pulley 38: Frame support section 40:Support structure 42: Guide rail 44: Spindle Housing 46: Screw shaft 48: Motor 50: Cutting blade 52: Upper imaging unit 54: Lower imaging unit 56:Connection part 58 :Light source 60: Lifting support mechanism 62: Touch panel 64: Control Unit 66: Processing Unit 68: Storage section 70: Drive unit 72: Imaging Unit 74: Judgment section 76: Hochi Department 78: Laser processing equipment 80: Base 82: Guide rail 84: Mobile Plate 86: Screw shaft 88: Motor 90: Guide rail 92: Mobile Plate 94: Screw shaft 96: Motor 98: Table base 100: Holding Table 102:Frame body 104: Porous plate 106: Clamp 108:Support structure 110: Guide rail 112: Mobile Plate 114: Motor 116: Support 118: Laser beam irradiation unit 120: Laser Oscillator 122: Housing (122a, 122b: Mirror) 124: Irradiation head (124a: Mirror, 124b: Focusing lens) 126: Imaging Unit 128: Expansion device 130: Drums 132: Imaging Unit 134: Light source 136: Support unit (136a: Support base, 136b: Gripping part, 136c: Rod)

Claims

1. An inspection method for checking whether an adhesive film is divided along each of several planned division lines after dividing a workpiece, which has its back side attached to a tape via an adhesive film, The imaging step involves irradiating the back side of the workpiece with light in a predetermined wavelength range that is reflected by the adhesive film, and using the light in the predetermined wavelength range where the adhesive film is present has a greater intensity than the area where it is not present to image the back side of the workpiece. A determination step in which the adhesive film is divided along each of the multiple division lines is determined by comparing the intensity of light in a predetermined wavelength range in the region corresponding to the multiple division lines captured in the imaging step with a predetermined threshold, If the determination step determines that the adhesive film is not divided along any of the multiple planned division lines, a notification step is provided to inform the system of that fact. An inspection method that includes the following features.

2. An inspection device for inspecting whether an adhesive film has been divided along each of several planned division lines after a workpiece, whose back side is attached to a tape via an adhesive film, has been divided along each of several planned division lines, A light source that irradiates the workpiece toward the back side with light in a predetermined wavelength range that is reflected by the adhesive film, An imaging unit for imaging the back side of the workpiece, A notification unit that notifies that the adhesive film has not been divided along any of the multiple planned division lines, The system comprises a light source, an imaging unit, and a control unit for controlling the notification unit, The control unit is, A storage unit that stores threshold values ​​used to determine whether or not the adhesive film is divided along each of the multiple planned division lines, An imaging unit controls the imaging unit to image the back side of the workpiece using light in the predetermined wavelength range, with the light source controlled to irradiate the back side of the workpiece with light in the predetermined wavelength range, where the intensity is greater in areas where the adhesive film is present than in areas where it is not present. A determination unit that determines whether or not the adhesive film is divided along each of the multiple division lines by comparing the intensity of light in a predetermined wavelength range in the region corresponding to the multiple division lines captured by the imaging unit with the threshold value, A notification unit controls the notification unit to notify the notification if the determination unit determines that the adhesive film is not divided along any of the multiple planned division lines. An inspection device equipped with the following features.

Images