Conveying mechanism, processing apparatus, and processing method

Abstract

To provide a novel transport mechanism, processing apparatus, and processing method using the same for transporting wafers in which device chips are stacked on a device formed on the upper surface, resulting in an uneven surface on the upper surface. [Solution] A transport mechanism comprising a holding part 42 for holding a wafer 2 and a moving means 44 for moving the holding part 42, wherein the holding part 42 comprises an annular sponge part 46 that is flexible and blocks the flow of air, a top plate 48 disposed at one end of the annular sponge part 46, and an opening 50 formed in the top plate 48 that communicates with a suction source V, and the wafer 2 is suction-held and transported by the free end of the annular sponge part 46.

Description

Technical Field

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[0001] The present invention relates to a conveying mechanism, a processing device, and a processing method.

Background Art

[0002] A wafer on which a plurality of devices such as ICs and LSIs are partitioned by a division planned line and formed on the surface is ground on the back surface by a grinding device, and the thinned wafer is divided into individual device chips by a dicing device or a laser processing device and used in electrical devices such as mobile phones and personal computers.

[0003] Also, as shown in Patent Document 1 below, for example, the divided individual device chips are stacked with their heights aligned. Therefore, in a wafer having a concavo-convex surface on which device chips are stacked corresponding to the devices formed on the wafer, the back surface of the device chips loaded by the grinding device is ground and the heights are aligned.

Prior Art Document

Patent Document

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when a wafer having concavo-convexities on its upper surface due to device chips being stacked on the devices formed on the upper surface is conveyed to a chuck table that constitutes a grinding device by being sucked and held by a suction pad of a conveying means, air may leak from the suction pad, making it impossible to smoothly convey the wafer and causing the wafer to drop.

[0006] The present invention has been made in view of the above facts, and its main technical problem is to provide a novel conveying mechanism, a processing device using the same, and a processing method in the conveyance of a wafer having concavo-convexities on its upper surface due to device chips being stacked on the devices formed on the upper surface. [Means for solving the problem]

[0007] According to the first aspect of the present invention, as a transport mechanism that solves the above-mentioned main technical problems, a transport mechanism for transporting wafers, It includes a holding part for holding a wafer and a moving means for moving the holding part, The holding part comprises a flexible annular sponge portion that blocks the flow of air, a top plate disposed at one end of the annular sponge portion, and an opening formed in the top plate that communicates with a suction source. A transport mechanism is provided that uses the free end of the annular sponge portion to suction and hold the wafer.

[0008] Preferably, a porous sponge is disposed in the cavity surrounded by the annular sponge portion and the top plate. The wafer is preferably an uneven wafer with multiple devices disposed on its upper surface.

[0009] Furthermore, according to a second aspect of the present invention, a processing apparatus for solving the above-mentioned main technical problems includes a cassette containing a plurality of wafers, a transport means for unloading wafers from the cassette and transporting them to a temporary receiving table, a transport means for loading wafers transported to the temporary receiving table into a chuck table, a processing means for processing wafers held on the chuck table, and an unloading means for unloading wafers from the chuck table. A processing apparatus is provided in which the loading means and the unloading means are composed of the above-described transport mechanism.

[0010] In this case, the processing means is preferably a grinding means that rotatably comprises a grinding wheel on which grinding wheels for grinding the uneven surfaces of a plurality of devices arranged on the upper surface of the wafer are arranged in an annular shape.

[0011] Furthermore, according to a third aspect of the present invention, as a processing method for solving the above-mentioned main technical problems, a processing method for an uneven wafer on which a plurality of devices are arranged on the upper surface, The process includes a transport step of unloading wafers from a cassette containing multiple wafers and transporting them to a temporary receiving table, an loading step of loading the wafers transported to the temporary receiving table into a chuck table using a loading means, a processing step of grinding and aligning the uneven surfaces of the wafers held in the chuck table, and an unloading step of unloading the wafers from the chuck table using an unloading means. The loading means and the unloading means are provided as a processing method comprising the above-mentioned transport mechanism. [Effects of the Invention]

[0012] The transport mechanism of the present invention includes a holding part for holding a wafer and a moving means for moving the holding part. The holding part comprises an annular sponge part that is flexible and blocks the flow of air, a top plate disposed at one end of the annular sponge part, and an opening formed in the top plate that communicates with a suction source. Since the wafer is held by suction at the free end of the annular sponge part, the annular sponge part flexibly conforms to the uneven surface of the wafer and adheres closely, suppressing air leakage and enabling reliable transport of the wafer, thus eliminating the problem of wafers falling due to poor transport.

[0013] Furthermore, the processing apparatus of the present invention includes a cassette containing a plurality of wafers, a transport means for unloading wafers from the cassette and transporting them to a temporary receiving table, a loading means for loading wafers transported to the temporary receiving table into a chuck table, a processing means for processing wafers held on the chuck table, and a loading means for unloading wafers from the chuck table. Since the loading means and the loading means are composed of the above transport mechanism, the annular sponge portion flexibly conforms to and adheres to the uneven surface of the wafer, suppressing air leakage and enabling reliable wafer transport, thus eliminating the problem of wafers falling due to poor transport.

[0014] Furthermore, in the processing method of the present invention, there are a conveying step of carrying out a wafer from a cassette containing a plurality of wafers and conveying it to a temporary receiving table, a loading step of loading the wafer conveyed to the temporary receiving table onto a chuck table by a loading means, a processing step of grinding and aligning the uneven heads of the wafer held on the chuck table, and an unloading step of unloading the wafer from the chuck table by an unloading means. Since the loading means and the unloading means are constituted by the above-described conveying mechanism, the air leakage is suppressed because the annular sponge portion flexibly follows and adheres to the uneven surface of the wafer, and it becomes possible to reliably convey the wafer, thereby solving the problem that the conveyance cannot be smoothly performed and the wafer drops.

Brief Description of the Drawings

[0015] [Figure 1] Perspective view of a preferred embodiment of a wafer conveyed by an unloading mechanism configured according to the present invention. [Figure 2] Perspective view of a preferred embodiment of a processing apparatus including an unloading mechanism configured according to the present invention. [Figure 3] Cross-sectional view of the loading means and the unloading means of the processing apparatus shown in FIG. 2. [Figure 4] Perspective view of a state where the loading means and the unloading means shown in FIG. 3 suck and hold and convey the wafer shown in FIG. 1. [Figure 5] Perspective view of the chuck table of the processing apparatus shown in FIG. 2. [Figure 6] Perspective view of a state where the processing means of the processing apparatus shown in FIG. 2 processes the wafer held on the chuck table.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, a more detailed description will be given with reference to the accompanying drawings showing preferred embodiments of a conveying mechanism, a processing apparatus, and a processing method configured according to the present invention.

[0017] <<Wafer>> Figure 1 shows a preferred embodiment of a wafer transported by an unloading mechanism configured according to the present invention. This wafer, shown as number 2 overall, comprises a wafer substrate 4 which can be formed from a suitable semiconductor material such as silicon. The wafer substrate 4 is generally thin-walled and disc-shaped, with notches 6 indicating the crystal orientation locally formed on its outer surface. Multiple lower layer devices 8a, such as ICs and LSIs, are formed on the surface 4a of the wafer substrate 4, demarcated by division lines 10. One upper layer device 8b is stacked on top of each lower layer device 8a. The upper layer device 8b is a single device chip removed from another wafer, which is removed by dividing all the division lines of the other wafer using a division means (not shown). The upper layer device 8b is stacked on top of the lower layer device 8a by a well-known bonding method. Therefore, in the illustrated embodiment, device 8 is composed of a lower layer device 8a and an upper layer device 8b stacked vertically, and the upper surface of wafer 2 has irregularities due to the presence of device 8 (more specifically, upper layer device 8b). Thus, wafer 2 is an irregular wafer with multiple devices 8 arranged on its upper surface.

[0018] <<Processing equipment>> Figure 2 shows a preferred embodiment of a processing apparatus including an unloading mechanism configured according to the present invention. The processing apparatus, shown as a whole as number 12, includes a cassette (first cassette 14), a transport means 16, a loading means 18, a processing means 20, and an unloading means 22. The processing apparatus 12 also includes a temporary receiving table 24 and a chuck table 26. In the illustrated embodiment, the processing apparatus 12 further includes a cleaning means 28 and a second cassette 30. These, namely the first cassette 14, transport means 16, loading means 18, processing means 20, unloading means 22, temporary receiving table 24, chuck table 26, cleaning means 28, and second cassette 30, are arranged on a substantially rectangular parallelepiped-shaped apparatus housing 32. In the following explanation using Figure 2, the front-to-back direction (forward or backward), left-to-right direction, and height direction are all based on the coordinate axes shown in the lower right of the figure. The front-to-back direction is represented by the Y-axis direction (the far side is the positive Y-axis), the left-to-right direction by the X-axis direction (the left side is the positive X-axis), and the height direction by the Z-axis direction.

[0019] <Cassette> The first cassette 14 and the second cassette 30 have the same configuration. They are both box-shaped and have a single opening surface 34, and can accommodate a plurality of wafers 2. The first cassette 14 and the second cassette 30 are on the front side of the device housing 32, and both opening surfaces 34 are positioned opposite to each other in the left-right direction with the conveying means 16 interposed therebetween. The first cassette 14 is disposed on the right side and the second cassette 30 is disposed on the left side, respectively.

[0020] <Conveying means> The conveying means 16 includes a holding piece 36 and a moving means 37 for moving the same. The moving means 37 includes a driving means not shown. By operating such a driving means, as will be described later, the holding piece 36 unloads the wafer 2 from the first cassette 14 and conveys it to the temporary receiving table 24, and also accommodates the wafer 2 washed by the cleaning means 28 into the second cassette 30.

[0021] <Temporary receiving table> The temporary receiving table 24 is disposed adjacent to and behind the first cassette 14 in the front-rear direction (Y-axis direction). The temporary receiving table 24 includes a plurality of support pieces 38 for supporting the outer peripheral surface of the wafer 2 and a displacement means not shown for displacing the same. By displacing the plurality of support pieces 38 by such a displacement means so that they support the outer peripheral surface of the wafer 2, as will be described later, the temporary receiving table 24 adjusts the center position of the wafer 2.

[0022] <Loading means and unloading means> The loading means 18 and the unloading means 22 have the same configuration. The loading means 18 is located adjacent to and behind the temporary receiving table 24 in the front-rear direction (Y-axis direction). On the other hand, the unloading means 22 is located adjacent to the loading means 18 on its left side. The loading means 18 and the unloading means 22 are composed of a transport mechanism configured according to the present invention. As will be described later, the loading means 18 loads the wafer 2 transported to the temporary receiving table 24 into the chuck table 26, and the unloading means 22 unloads the wafer 2 from the chuck table 26. In the illustrated embodiment, the unloading means 22 loads the wafer 2 unloaded from the chuck table 26 into the washing means 28. The transport mechanism configured according to the present invention will be explained with reference to Figures 3 and 4. The transport mechanism, shown as number 40 overall, includes a holding part 42 for holding the wafer 2 and a moving means 44 for moving the holding part 42.

[0023] The holding portion 42 further comprises an annular sponge portion 46 and a top plate 48 disposed at one end of the annular sponge portion 46. An opening 50 is formed in the top plate 48. In the illustrated embodiment, the top plate 48 is a thin disc shape, and the opening 50 is formed in the center of the top plate 48. The annular sponge portion 46 is fixed to the outer peripheral edge of the lower surface of the top plate 48 by an appropriate fixing method such as adhesive, and the inner diameter of the annular sponge portion 46 is sufficiently larger than the diameter of the opening 50. Therefore, the annular sponge portion 46 is ring-shaped. In the illustrated embodiment, a disc-shaped porous sponge 52 is disposed in the space surrounded on three sides by the inner circumferential surface of the annular sponge portion 46 and the lower surface of the top plate 48. The porous sponge 52 has relatively high rigidity and extremely high breathability, and its upper surface is fixed to the lower surface of the top plate 48 by an appropriate fixing method such as adhesive. A connecting tube 54 is connected to the upper surface of the top plate 48, encircling the outer edge of the opening 50 and extending upward. A connecting hole 56 is formed at the upper end of the connecting tube 54, connecting the inner surface to the outer surface, and a connecting tube 58 is formed on the outer surface of the connecting tube 54, encircling the outer edge of the connecting hole 56 and extending laterally. A disc-shaped guide portion 60 is connected to the upper end of the connecting tube 54. The central axes of the guide portion 60 and the connecting tube 54 are aligned. The guide portion 60 will be described later.

[0024] The moving means 44 comprises a support base 61 erected on the upper surface of the device housing 32 and a rod-shaped support member 62 rotatably connected to the upper end of the support base 61. The support member 62 extends linearly horizontally with the support base 61 as its base. The moving means 44 is further equipped with a driving means (not shown), and by driving this, as shown by the arrow in Figure 4, the support base 61 becomes extendable and retractable in the height direction, i.e., the Z-axis direction, and the support member 62 becomes rotatable around the Z-axis, i.e., in the XY plane, with the support base 61 as its axis. A through hole 64 is formed in the free end of the support member 62, penetrating in the vertical direction. The vertical length of the through hole 64 is shorter than the vertical length of the communication cylinder 54 of the holding part 42. A circular recess 66 is also formed on the upper surface of the free end of the support member 62. The center of the recess 66 aligns with the center of the through hole 64, and the diameter of the recess 66 is larger than the diameter of the through hole 64. A connecting hole 68 is also formed inside the support member 62, extending laterally from the through hole 64 toward the base end.

[0025] The holding portion 42 and the moving means 44 are assembled by housing the communication cylinder 54 of the holding portion 42 in the through hole 64 of the support member 62 and housing the connecting cylinder 58 of the holding portion 42 in the connecting hole 68 of the support member 62, and then fixing the guide portion 60 to the upper end of the communication cylinder 54 by an appropriate method. The outer diameter of the disc-shaped guide portion 60 corresponds to the diameter of the circular recess 66, more specifically, it is the same as or slightly smaller than this, and larger than the diameter of the through hole 64. Therefore, in the holding portion 42 and the moving means 44 assembled in this way, the holding portion 42 is movable vertically relative to the support member 62, while the lower surface of the guide portion 60 is locked to the upper surface of the support member 62 in the recess 66, preventing the holding portion 42 from falling off the support member 62 (i.e., the moving means 44). When the holding portion 42 moves vertically relative to the support member 62, the outer circumferential surface of the guide portion 60 faces the inner circumferential surface of the support member 62 that defines the recess 66, thereby stabilizing the posture of the holding portion 42. A hose 70 is inserted through the connection hole 68 of the support member 62, with one end connected to the connection cylinder 58 of the holding portion 42 and the other end connected to the suction source V. In the illustrated embodiment, a coil spring 74 is disposed between the upper surface of the top plate 48 and the lower surface of the support member 62. A communication cylinder 54 is inserted inside the coil spring 74, and the upper end of the coil spring 74 is housed in the recess 76 formed on the lower surface of the support member 62.

[0026] <Chuck Table> In the illustrated embodiment, the chuck table 26 is positioned on a turntable 78 adjacent to and behind the loading means 18 and unloading means 22 in the front-rear direction (Y-axis direction). The turntable 78 is a relatively large-diameter disc shape and is positioned within a drain pan 80 formed on the upper surface of the device housing 32. The upper surface of the turntable 78 is substantially flush with the upper surface of the device housing 32. The center of the turntable 78 is located approximately in the left-right center of the upper surface of the device housing 32, and the turntable 78 is rotated appropriately in the direction indicated by arrow R1 by a rotational drive mechanism (not shown). Three chuck tables 26 are arranged on the turntable 78 at equal angular intervals in the circumferential direction and are rotated in the direction indicated by arrow R2 by a rotational drive mechanism (not shown). The holding surface, i.e., the upper surface, of the chuck table 26 is formed of a breathable material (see Figure 5) and is connected to a suction means (not shown). By operating this suction means, wafers 2 placed on the holding surface can be held by suction to the chuck table 26. Then, by rotating the turntable 78 120 degrees in the direction indicated by arrow R1, the chuck table 26 mounted on the turntable 78 can move sequentially from workpiece loading / unloading area A → rough grinding area B → finish grinding area C → workpiece loading / unloading area A. Near workpiece loading / unloading area A in the drain pan 80, a washing water supply nozzle 82 is provided to supply washing water to the upper surface of the chuck table 26 positioned in workpiece loading / unloading area A.

[0027] <Processing means> In the illustrated embodiment, the processing means 20 is a grinding means that rotatably includes a grinding wheel on which grinding wheels are arranged in an annular pattern, and the grinding means includes a rough grinding unit 84a and a finish grinding unit 84b. The rough grinding unit 84a is located directly above and to the right of the rough grinding area B, and the finish grinding unit 84c is located directly above and to the left of the finish grinding area C. The rough grinding unit 84a includes a rough grinding wheel 88a on which a plurality of rough grinding wheels 86a are arranged in an annular pattern on its lower surface, and an electric motor 90a for rotating the rough grinding wheel 88a. Similarly, the finish grinding unit 84b includes a finish grinding wheel 88b on which a plurality of finish grinding wheels 86b are arranged in an annular pattern on its lower surface, and an electric motor 90b for rotating the finish grinding wheel 88b.

[0028] The processing means 20, or grinding means, also includes a rough grinding feed mechanism 92a as a lifting means for raising and lowering the rough grinding unit 84a in the vertical direction (Z-axis direction), and a finish grinding feed mechanism 92b as a lifting means for raising and lowering the finish grinding unit 84b in the vertical direction (Z-axis direction). The rough grinding feed mechanism 92a and the finish grinding feed mechanism 92b are arranged in parallel in the left-right direction on the front surface of a support wall 32a erected at the rear end of the device housing 32, with the former on the right side and the latter on the left side.

[0029] <Cleaning methods> The cleaning means 28 is located between the discharge means 22 and the second cassette 30. The cleaning means 28 includes a spinner table 96, a cleaning nozzle (not shown), and an air injection nozzle, within a cleaning space defined by number 94. The upper surface of the spinner table 96, like the chuck table 26, is formed of a breathable material and connected to a suction means (not shown), which can be used to hold a wafer 2 placed on its upper surface by suction. The spinner table 96 is connected to a rotational drive mechanism (not shown), which rotates the spinner table 96 around the Z-axis. The cleaning nozzle can supply cleaning water to the upper surface of the wafer 2 held by suction on the upper surface of the spinner table 96. The air injection nozzle can remove any remaining cleaning water from the upper surface of the wafer 2 by spraying high-pressure air, thereby drying the upper surface of the wafer 2.

[0030] <<Processing method>> Next, a processing method for processing the wafer 2 using the processing apparatus 12 described above will be explained. This processing method includes a transport process, a loading process, a processing process, and an unloading process. In the illustrated embodiment, a cleaning process and a storage process are also included.

[0031] <Conveying Process> In the transport process, the transport means 16, more specifically its holding piece 36, unloads the wafers 2 from the first cassette 14 (cassette) containing multiple wafers 2 and transports them to the temporary receiving table 24. The wafers 2 are transported to the temporary receiving table 24 with the surface 4a of the wafer substrate 4 facing upwards, and the bottom surface of the wafers 2 is placed on the top surface of the temporary receiving table 24. On the temporary receiving table 24, the support piece 38 is appropriately displaced to adjust the center position of the transported wafers 2.

[0032] <Delivery process> Following the transport process, the loading process is carried out. In the loading process, the loading means 18 loads the wafer 2 from the temporary receiving table 24 to the chuck table 26. In the loading process as well, the wafer 2 is loaded onto the chuck table 26 with the surface 4a of the wafer substrate 4 facing upwards (see Figure 5). The loading process will be described in more detail below.

[0033] As described above, the loading means 18 is equipped with a transport mechanism 40 configured according to the present invention. In the loading process, first, the moving means 44 is operated to position the lower surface of the holding part 42 at the required position (e.g., the center) on the upper surface of the wafer 2. At this time, the suction source V is still in a non-operating state. Next, the suction source V is switched from a non-operating state to an operating state. In this way, the opening 50 of the top plate 48 is subjected to negative pressure through the hose 70, connecting cylinder 58, and communication cylinder 54. At this time, the annular sponge part 46 disposed on the outer peripheral edge of the lower surface of the top plate 48 is flexible and blocks the flow of air, so a force acting radially inward on the annular sponge part 46 due to the negative pressure acts on the annular sponge part 46, causing it to deform radially inward. However, in the illustrated embodiment, a porous sponge 52 with relatively high rigidity is disposed in the cavity surrounded by the annular sponge part 46 and the top plate 48, so the above deformation of the annular sponge part 46 is prevented. Furthermore, since the porous sponge 52 also has extremely high permeability, the opening 50 can sufficiently suction even through the porous sponge 52. When the opening 50 is subjected to negative pressure, as shown in Figure 4, the free end of the annular sponge portion 46, and more specifically the inner region of the annular sponge portion 46, suction and hold the upper surface of the wafer 2. At this time, even if there are irregularities on the upper surface of the wafer 2, because the annular sponge portion 46 is flexible, the lower surface of the annular sponge portion 46 deforms to conform to the irregularities on the upper surface of the wafer 2 and adheres tightly, so air leakage is suppressed and the transport mechanism 40 can reliably transport the wafer 2. In the illustrated embodiment, the holding portion 42 is movable vertically relative to the moving means 44 (support member 62), and a coil spring 74 is disposed between the holding portion 42 and the support member 62. Therefore, even if the lower surface of the holding portion 42 forcefully collides with the upper surface of the wafer 2 when the holding portion 42 suction-holds the wafer 2, the impact from such a collision is sufficiently absorbed as the holding portion 42 rises relative to the support member 62 and the coil spring 74 compresses. Thus, the lower surface of the holding portion 42 does not damage the device 8 formed on the upper surface of the wafer 2.Then, while the suction source V remains in operation, the moving means 44 is activated to position the wafer 2, which is held by the holding unit 42, on the upper surface of the chuck table 26 located in the workpiece loading / unloading area A. After that, the suction source V is switched from the operating state to the non-operating state, and the suction means connected to the chuck table 26 is activated to hold the wafer 2 on the upper surface of the chuck table 26 by suction. Thus, the wafer 2 is loaded onto the chuck table 26.

[0034] <Processing process> Following the loading process, the processing process is carried out. In the processing process, the tops of the irregularities on the wafer 2 held in the chuck table 26 are ground down to make their heights uniform. In this process, rough grinding is performed, followed by finishing. In the rough grinding process, first, the turntable 78 is rotated 120 degrees in the direction indicated by arrow R1 in Figure 2 to position the chuck table 26, which holds the wafer 2 by suction, directly below the rough grinding unit 84a, i.e., in the rough grinding area B. Next, as shown in Figure 6, the chuck table 26 is rotated at, for example, 300 rpm in the direction indicated by arrow R2, while the rough grinding wheel 88a of the rough grinding unit 84a is rotated at, for example, 6000 rpm in the direction indicated by arrow R3. Then, the rough grinding feed mechanism 92a described above is activated to bring the rough grinding wheel 86a into contact with the surface of the wafer 2, and the rough grinding wheel 88a is fed downward at a speed of, for example, 1.0 μm / second. At this time, grinding water is supplied to the surface of the wafer 2 from the lower surface of the rough grinding wheel 88a. Simultaneously, grinding can be carried out while measuring the thickness of the wafer 2 using a non-contact measuring means (not shown), and the surface of the wafer 2 is roughly ground to the desired thickness for rough grinding, completing the rough grinding process.

[0035] Following the rough grinding process described above, finish grinding is performed. In the finish grinding process, first, the turntable 78 is rotated 120 degrees in the direction indicated by arrow R1 in Figure 2 to position the chuck table 26 directly below the finish grinding unit 84b, i.e., in the finish grinding area C. Next, as shown in Figure 6, the chuck table 26 is rotated at, for example, 300 rpm in the direction indicated by arrow R2, while the finish grinding wheel 88b of the finish grinding unit 84b is rotated at, for example, 6000 rpm in the direction indicated by arrow R3. Then, the finish grinding feed mechanism 92b described above is activated to bring the grinding wheel 86b for finish grinding into contact with the surface of the wafer 2, and the finish grinding wheel 88b is fed downward at a speed of, for example, 0.1 μm / second. At this time, grinding water is supplied to the surface of the wafer 2 from the lower surface of the finish grinding wheel 88b. Simultaneously, grinding can be carried out while measuring the thickness of wafer 2 using a non-contact measuring means (not shown), and the surface of wafer 2 is finished grinding to the desired thickness for the finish grinding process, thus completing the finish grinding. In this way, the tops of the irregularities on the surface of wafer 2 held in the chuck table 26 are ground and leveled.

[0036] <Export process> Following the processing process, the unloading process is carried out. In the unloading process, the wafer 2 is unloaded from the chuck table 26 by the unloading means 22. In the unloading process, first, the turntable 78 is rotated another 120 degrees in the direction indicated by arrow R1 in Figure 2 to position the chuck table 26 in the workpiece loading / unloading area A, and pre-cleaning is performed by supplying cleaning water from the cleaning water supply nozzle 82 to roughly remove grinding debris. After that, the wafer 2 positioned in the workpiece loading / unloading area A is unloaded by the unloading means 22. In the illustrated embodiment, the wafer 2 is transported from the chuck table 26 positioned in the workpiece loading / unloading area A to the cleaning means 28. The unloading means 22 is equipped with a transport mechanism 40 configured according to the present invention, and the configuration and operation of the unloading means 22 are substantially the same as the configuration and operation of the loading means 18, so a detailed explanation of the unloading means 22 is omitted. The wafer 2, which has been transported to the washing means 28, is placed on the upper surface of the spinner table 96.

[0037] <Washing process> Following the processing process, a cleaning process is carried out. In the cleaning process, the upper surface of the processed wafer 2 is cleaned. By driving a suction means (not shown) connected to the upper surface of the spinner table 96, the wafer 2 transported to the cleaning means 28 is held by suction on the upper surface of the spinner table 96. Subsequently, by operating a rotation drive mechanism connected to the spinner table 96, the spinner table 96 and the wafer 2 held by suction on its upper surface are rotated. After that, a cleaning nozzle (not shown) is operated to supply cleaning water to the upper surface of the wafer 2 to remove debris such as cutting chips remaining on the upper surface of the wafer 2, and then an air injection nozzle (not shown) is operated to remove the cleaning water remaining on the upper surface of the wafer 2 and dry the upper surface of the wafer 2.

[0038] <Storage Process> Following the cleaning process, the storage process is carried out. In the storage process, the transport means 16 stores the cleaned wafer 2 in the second cassette 30. In the storage process as well, the wafer 2 is transported to the second cassette 30 with the surface 4a of the wafer substrate 4 facing upwards.

[0039] Accordingly, the transport mechanism 40 of the present invention includes a holding part 42 for holding the wafer 2 and a moving means 44 for moving the holding part 42. The holding part 42 comprises an annular sponge part 46 that is flexible and blocks the flow of air, a top plate 48 disposed at one end of the annular sponge part 46, and an opening 50 formed in the top plate 48 that communicates with a suction source V. Since the wafer 2 is held by suction at the free end of the annular sponge part 46, the annular sponge part 46 flexibly conforms to the uneven surface of the wafer 2 and adheres closely, suppressing air leakage and enabling reliable transport of the wafer 2, thus eliminating the problem of the wafer 2 falling due to poor transport.

[0040] Furthermore, the processing apparatus 12 of the present invention includes a first cassette 14 containing a plurality of wafers 2, a transport means 16 for unloading the wafers 2 from the first cassette 14 and transporting them to a temporary receiving table 24, a loading means 18 for loading the wafers 2 transported to the temporary receiving table 24 into a chuck table 26, a processing means 20 for processing the wafers 2 held on the chuck table 26, and a loading means 22 for unloading the wafers 2 from the chuck table 26. Since the loading means 18 and the unloading means 22 are composed of the transport mechanism 40, the annular sponge portion 46 flexibly conforms to and adheres to the uneven surface of the wafer 2, suppressing air leakage and enabling reliable transport of the wafers 2, thus eliminating the problem of wafers 2 falling due to poor transport.

[0041] Furthermore, the processing method of the present invention includes a transport step of unloading wafers 2 from a first cassette 14 containing a plurality of wafers 2 and transporting them to a temporary receiving table 24, a loading step of loading the wafers 2 transported to the temporary receiving table 24 to a chuck table 26 using a loading means 18, a processing step of grinding and aligning the uneven surfaces of the wafers 2 held on the chuck table 26, and an unloading step of unloading the wafers 2 from the chuck table 26 using an unloading means 22. Since the loading means 18 and the unloading means 22 are composed of the transport mechanism 40, the annular sponge portion 46 flexibly conforms to and adheres to the uneven surface of the wafers 2, suppressing air leakage and enabling reliable transport of the wafers 2, thus eliminating the problem of wafers 2 falling due to poor transport.

[0042] Although the transport mechanism, processing apparatus, and processing method configured according to the present invention have been described in detail above with reference to the attached drawings, the present invention is not limited to the embodiments described above, and appropriate modifications and changes are possible without departing from the present invention. In the embodiments described above, the processing means 20 was a grinding means, but this may be a cutting means or the like, or a combination of multiple means such as grinding means and cutting means may be used. Therefore, the unloading means (unloading process) is not limited to unloading the wafer from the chuck table to the cleaning means. Also, in the illustrated embodiment, the device 8 was composed of two layers consisting of a lower layer device 8a and an upper layer device 8b, but it may be composed of three or more layers. [Explanation of Symbols]

[0043] 2: Wafer 8: Devices 12: Processing equipment 14: First Cassette (Cassette) 16: Conveying means 18: Delivery method 20: Processing means 22:Export means 24: Temporary support table 26: Chuck Table 40: Conveying mechanism 42: Holding part 44: Means of transportation 46: Ring-shaped sponge section 48: Top plate 50: Opening V: Suction source

Claims

1. A conveying mechanism for transporting wafers, It includes a holding part for holding a wafer and a moving means for moving the holding part, The holding part comprises a flexible annular sponge portion that blocks the flow of air, a top plate disposed at one end of the annular sponge portion, and an opening formed in the top plate that communicates with a suction source. A transport mechanism that uses suction to hold a wafer at the free end of the annular sponge portion.

2. The transport mechanism according to claim 1, wherein a porous sponge is disposed in the cavity surrounded by the annular sponge portion and the top plate.

3. The transport mechanism according to claim 1, wherein the wafer is an uneven wafer on which a plurality of devices are arranged on its upper surface.

4. A processing apparatus comprising: a cassette containing a plurality of wafers; a transport means for unloading wafers from the cassette and transporting them to a temporary receiving table; a loading means for loading wafers transported to the temporary receiving table into a chuck table; a processing means for processing wafers held on the chuck table; and an unloading means for unloading wafers from the chuck table. A processing apparatus wherein the loading means and the unloading means are composed of the transport mechanism described in any one of claims 1 to 3.

5. The processing apparatus according to claim 4, wherein the processing means is a grinding means comprising a rotatable grinding wheel on which grinding wheels for grinding the uneven surfaces of a plurality of devices disposed on the upper surface of a wafer are arranged in an annular manner.

6. A method for processing a wafer with multiple devices arranged on its upper surface, The process includes a transport step of unloading wafers from a cassette containing multiple wafers and transporting them to a temporary receiving table, an loading step of loading the wafers transported to the temporary receiving table into a chuck table using a loading means, a processing step of grinding and aligning the uneven surfaces of the wafers held in the chuck table, and an unloading step of unloading the wafers from the chuck table using an unloading means. A processing method comprising a transport mechanism according to any one of claims 1 to 3, wherein the transport means and the transport means are configured as described in any one of claims 1 to 3.

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