Grinding Equipment

Abstract

To provide a processing device which enables installation in a saved space and continuously processes a wafer by grinding with a simple configuration.SOLUTION: A processing device 1 comprises: a plurality of chucks 22 for chucking and holding a wafer W; and an index table 21, which keeps a plurality of chucks 22 arranged to transport the plurality of chucks 22 between rough grinding means 4 and medium grinding means 5 and precise grinding means 6. The rough grinding means 4 and the medium grinding means 5 are arranged on the index table 21 so that a circular arc C formed on a grinding target surface of the wafer W with a rough grinding whetstone 41 of the rough grinding means 4 brought into contact with the grinding target surface and a circular arc C formed on the grinding target surface of the wafer W with a medium grinding whetstone of the medium grinding means 5 brought into contact with the grinding target surface may cross each other when the wafer W rotates within the grinding target surface to be processed by grinding.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a grinding apparatus for grinding a wafer. [Background technology]

[0002] 2. Description of the Related Art In the field of semiconductor manufacturing, back grinding is performed to grind the back surface of a semiconductor wafer such as a silicon wafer (hereinafter referred to as a "wafer") to form a thin film.

[0003] Patent Document 1 discloses a processing device that includes a mechanism for tilting the rotation axis of a rough grinding wheel that rough grinds a wafer, and a mechanism for tilting the rotation axis of a chuck, and that performs fine grinding following rough grinding by rotating an index table after rough grinding.

[0004] It is generally known that in order to properly press the grindstone against the wafer, it is preferable that the rotation axis of the grindstone and the rotation axis of the chuck are slightly inclined.

[0005] In the above-mentioned processing apparatus, since the contact conditions between the rough grinding wheel and the wafer and the contact conditions between the fine grinding wheel and the wafer are different, first the inclination of the chuck is adjusted based on the fine grinding wheel so that the fine grinding wheel properly contacts the wafer after rough grinding, and then the inclination of the rough grinding wheel is adjusted based on the chuck, thereby reducing the variation in the wafer's total thickness variation (TTV) between chucks. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6283081 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the above-mentioned processing device requires a mechanism for tilting the rotation axis of the rough grinding wheel so as to reproduce the contact condition between the fine grinding wheel and the chuck, which makes the device configuration complicated.

[0008] It is also possible to change the layout of the rough grinding wheels and fine grinding wheels to correspond to the arrangement of the chuck, but changing the layout in which the rough grinding wheels and fine grinding wheels are offset to the outside of the chuck would increase the distance between the rough grinding wheels and fine grinding wheels, resulting in an increase in the size of the device.

[0009] Therefore, there is a technical problem to be solved, which is to provide a space-saving installation apparatus with a simple configuration that can continuously perform wafer grinding processing. An object of the present invention is to solve this problem. [Means for solving the problem]

[0010] In order to achieve the above object, a grinding apparatus according to the present invention is a grinding apparatus for continuously grinding wafers with a plurality of grinding means, comprising: a plurality of chucks for suction-holding the wafers and tilting by each tilt mechanism with respect to a tilt axis; and an index table for arranging the plurality of chucks and transporting the plurality of chucks between the plurality of grinding means, the plurality of grinding means including at least a rough grinding mechanism having a rough grinding wheel for grinding the wafers, a medium grinding mechanism having a medium grinding wheel for grinding the wafers, and a fine grinding mechanism having a fine grinding wheel for grinding the wafers, and wherein, in a plan view, the rough grinding wheel comes into contact with the contact surface of the wafer held by suction on the chucks, forming a center of rotation of the wafer on the contact surface, and two intersections where the tilt axis intersects with the outer periphery of the chuck. The rough grinding mechanism and the medium grinding mechanism are disposed with respect to the index table so that a first arc having an end point at one of the intersections where the center of rotation and the tilt axis intersect with the outer periphery of the chuck, which are formed on the contact surface by the medium grinding wheel coming into contact with the contact surface, and a second arc having an end point at one of the intersections where the center of rotation and the tilt axis intersect with the outer periphery of the chuck, which are formed on the contact surface by the medium grinding wheel coming into contact with the contact surface, intersect with each other when the wafer is rotated within the contact surface to be ground. The medium grinding mechanism and the fine grinding mechanism are disposed with respect to the index table so that, when viewed from a plane, the second arc and a third arc having an end point at one of the intersections where the center of rotation and the tilt axis intersect with the outer periphery of the chuck, which are formed on the contact surface by the fine grinding wheel coming into contact with the contact surface, intersect with each other when the wafer is rotated within the contact surface to be ground. Effect of the Invention

[0011] In the present invention, since the rough grinding wheel, medium grinding wheel and fine grinding wheel contact all of the chucks in the same way, by adjusting the contact condition of one of the rough grinding wheel, medium grinding wheel or fine grinding wheel, the trouble of adjusting the contact condition between the other grinding wheels and the chuck can be eliminated, and the contact condition between each processing means and the chuck can be appropriately adjusted while maintaining the size of the device, without providing a mechanism for tilting the rotation axes of multiple grinding means. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing a processing device according to an embodiment of the present invention; [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. 5 is a plan view in which the column and various grinding devices shown in FIG. 4 are omitted. [Figure 6] 6 is a cross-sectional view taken along line AA in FIG. 5. [Figure 7] FIG. 11 is a plan view showing a schematic arrangement of grinding wheels and a chuck in a conventional processing device. [Figure 8] FIG. 4 is a plan view showing a schematic arrangement of the grinding wheels and the chucks; [Figure 9] FIG. 11 is a plan view showing another arrangement position of the grinding wheel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] An embodiment of the present invention will be described with reference to the drawings. In the following, when the number, numerical value, amount, range, etc. of components are mentioned, the number is not limited to the specific number, and may be more than or less than the specific number, unless otherwise specified or when it is clearly limited to a specific number in principle.

[0014] In addition, when referring to the shape or positional relationship of components, etc., this includes things that are substantially similar or approximate to those shapes, etc., unless otherwise specified or considered to be clearly different in principle.

[0015] In addition, the drawings may exaggerate characteristic parts to make the features easier to understand, and the dimensional ratios of the components may not be the same as the actual ones. In addition, in cross-sectional views, hatching of some components may be omitted to make the cross-sectional structure of the components easier to understand.

[0016] Fig. 1 is a perspective view showing the processing apparatus 1 as viewed from one side. Fig. 2 is a perspective view showing the processing apparatus 1 as viewed from the other side. Fig. 3 is a front view of the processing apparatus 1. Fig. 4 is a plan view of the processing apparatus 1. Fig. 5 is a plan view omitting the column 3 and various grinding devices.

[0017] The processing device 1 continuously grinds the wafer W with three grindstones. The processing device 1 may continuously process the wafer W with two grindstones or may continuously process the wafer W with four or more grindstones. The processing device 1 grinds the back surface of the wafer W to form a thin film. The wafer W to be ground using the processing device 1 is preferably a silicon wafer, a silicon carbide wafer, or the like, which exhibits high hardness and high brittleness, but is not limited thereto. The processing device 1 includes a holding means 2 and a main unit arranged above the holding means 2.

[0018] The holding means 2 includes an index table 21 that is rotatable about a rotation axis a1 connected to a motor (not shown), and four chucks 22 placed on the index table 21.

[0019] The chucks 22 are arranged at 90 degree intervals on a circumference centered on the rotation axis a1. The chucks 22 are provided with an adsorbent made of porous ceramic embedded in the upper surface. A conduit formed in the chuck 22 is connected to a vacuum source (not shown), and the wafer W placed on the chuck 22 is adsorbed by negative pressure. The chuck 22 is connected to a motor (not shown) and can rotate around the rotation axis a2.

[0020] The holding means 2 is divided into an alignment stage S1, a rough grinding stage S2, a medium grinding stage S3, and a fine grinding stage S4.

[0021] At the alignment stage S1, the wafer W is transferred onto the chuck 22 by a transfer device (not shown) and aligned at a predetermined position. The wafer W held by suction on the chuck 22 is sent to the rough grinding stage S2.

[0022] In the rough grinding stage S2, the wafer W is roughly ground. The rotation speed of the chuck 22 in the rough grinding stage S2 is set to, for example, 310 rpm. The wafer W that has been roughly ground is sent to the medium grinding stage S3.

[0023] In the medium grinding stage S3, the wafer W is subjected to medium grinding. The rotation speed of the chuck 22 in the medium grinding stage S3 is set to, for example, 320 rpm. The wafer W that has been subjected to the medium grinding is sent to the fine grinding stage S4.

[0024] In the precision grinding stage S4, the wafer W is precision ground. The rotation speed of the chuck 22 in the precision grinding stage S4 is set to, for example, 300 rpm. The wafer W that has been precision ground is sent to the alignment stage S1 and is then transferred from the chuck 22 to a rack or the like (not shown) by a transport device or the like (not shown).

[0025] The main unit comprises an arch-shaped column 3 arranged to straddle the index table 21, a rough grinding means 4 attached to the column 3 above the rough grinding stage S2, a medium grinding means 5 attached to the column 3 above the medium grinding stage S3, and a fine grinding means 6 attached to the column 3 above the fine grinding stage S4.

[0026] The column 3 includes a base 31 formed in a U-shape when viewed from the front, and central pillars 32 and 33 protruding from the center of the base 31 in the front and rear directions.

[0027] The base 31 is provided so as to straddle the rough grinding stage S2, the medium grinding stage S3, and the fine grinding stage S4. As a result, in a plan view, the alignment stage S1 is exposed to the side of the column 3. Therefore, when the wafer W is transported to or removed from the chuck 22, a transport device or the like can access the chuck 22 without being interfered with by the column 3. The rigidity of the base 31 is increased by connecting two support pillars 31a erected on the outer periphery of the index table 21.

[0028] The central pillar portion 32 is disposed on the opposite side of the support pillar 31a across the rough grinding stage S2 in plan view. The central pillar portion 33 is disposed between the medium grinding stage S3 and the fine grinding stage S4 in plan view. The lower ends of the central pillar portions 32 and 33 extend above the index table 21.

[0029] A groove 3b is disposed on the front surface 3a of the column 3, the groove 3b being recessed in the vertical direction V. A rough grinding means 4 is housed in the groove 3b. Grooves 3d and 3e are disposed side by side on the rear surface 3c of the column 3, the grooves 3d and 3e being recessed in the vertical direction V. A medium grinding means 5 is housed in the groove 3e. A fine grinding means 6 is housed in the groove 3e.

[0030] The rough grinding means 4 includes a rough grinding wheel 41, a first spindle 42 having the rough grinding wheel 41 attached to its lower end, and a first spindle feed mechanism 43 that raises and lowers the first spindle 42 in the vertical direction V.

[0031] The rough grinding wheel 41 is configured by arranging a plurality of cup-shaped grinding wheels at the lower end in the circumferential direction. The grit size of the rough grinding wheel 41 is set to, for example, #2000.

[0032] The first spindle 42 includes a saddle 42a having the rough grinding wheel 41 attached to its lower end, and a motor (not shown) provided in the saddle 42a to rotate the rough grinding wheel 41. The rotation speed of the rough grinding wheel 41 is set to, for example, 3000 rpm.

[0033] The first spindle feed mechanism 43 connects the saddle 42a and a rear guide 72, which will be described later, and feeds the first spindle 42 in the vertical direction V. Note that the first spindle feed mechanism 43 does not include a lifting means for feeding the first spindle 42, but the lifting means may be, for example, a motor-driven ball screw.

[0034] The medium grinding means 5 includes a medium grinding wheel 51, a second spindle 52 having the medium grinding wheel 51 attached to its lower end, and a second spindle feed mechanism 53 that raises and lowers the second spindle 52 in the vertical direction V.

[0035] The medium grinding wheel 51 is configured by arranging a plurality of cup-shaped grinding wheels at the lower end in the circumferential direction. The grit size of the medium grinding wheel 51 is set to, for example, #4000.

[0036] The second spindle 52 includes a saddle 52a having the medium grinding wheel 51 attached to its lower end, and a motor (not shown) that is provided in the saddle 52a and rotates the medium grinding wheel 51. The rotation speed of the medium grinding wheel 51 is set to, for example, 2000 rpm.

[0037] The second spindle feed mechanism 53 has a configuration similar to that of the first spindle feed mechanism 43, and connects the saddle 52a to a rear guide 82, which will be described later, and feeds the second spindle 52 in the vertical direction V.

[0038] The precision grinding means 6 includes a precision grinding wheel 61, a third spindle 62 having the precision grinding wheel 61 attached to its lower end, and a third spindle feed mechanism 63 that raises and lowers the third spindle 62 in the vertical direction V.

[0039] The precision grinding wheel 61 is configured by arranging a plurality of cup-shaped grinding wheels at the lower end in the circumferential direction. The grit size of the precision grinding wheel 61 is set to, for example, #8000.

[0040] The third spindle 62 includes a saddle 62a having the precision grinding wheel 61 attached to its lower end, and a motor (not shown) that is provided in the saddle 62a and rotates the precision grinding wheel 61. The rotation speed of the precision grinding wheel 61 is set to, for example, 2000 rpm.

[0041] The third spindle feed mechanism 63 has a configuration similar to that of the first spindle feed mechanism 43, and connects the saddle 62a to a rear guide 92, which will be described later, and feeds the third spindle 62 in the vertical direction V.

[0042] The processing apparatus 1 is provided with an in-process gauge (not shown) for measuring the thickness of the wafer W during processing. The in-process gauges are disposed on the rough grinding stage S2, the medium grinding stage S3, and the fine grinding stage S4, respectively. The operations of the first spindle feed mechanism 43, the second spindle feed mechanism 53, and the third spindle feed mechanism 63 are controlled based on the film thickness measured by the in-process gauge.

[0043] Specifically, when the thickness of the wafer W measured by the in-process gauge provided on the rough grinding stage S2 reaches a desired value, the first spindle feed mechanism 43 is driven to raise the saddle 42a, thereby separating the wafer W from the rough grinding wheel 41. Similarly, when the thickness of the wafer W measured by the in-process gauge provided on the medium grinding stage S3 reaches a desired value, the wafer W is separated from the medium grinding wheel 51, and when the thickness of the wafer W measured by the in-process gauge provided on the fine grinding stage S4 reaches a desired value, the wafer W is separated from the fine grinding wheel 61.

[0044] The processing apparatus 1 is provided with a first guide 7 that supports the first spindle 42 so that it can slide in the vertical direction V, a second guide 8 that supports the second spindle 52 so that it can slide in the vertical direction V, and a third guide 9 that supports the third spindle 62 so that it can slide in the vertical direction V.

[0045] The first guide 7 is composed of a front guide 71 disposed on the front surface of the base 31 and the central pillar 32, respectively, and a rear guide 72 disposed in the groove 3b. The front guide 71 and the rear guide 72 are, for example, linear guides. A saddle 42a is directly attached to a slider 71a of the front guide 71. In addition, a saddle 42a is attached to the rear guide 72 via a first spindle feed mechanism 43.

[0046] The front guide 71 and the rear guide 72 are provided in parallel to each other along the vertical direction V. As a result, the front guide 71 and the rear guide 72 regulate the saddle 42a so that it moves along the vertical direction V.

[0047] The second guide 8 is composed of a front guide 81 disposed on the rear surface of the base 31 and the central pillar 33, respectively, and a rear guide 82 disposed in the groove 3d. The front guide 81 and the rear guide 82 are, for example, linear guides. A saddle 52a is directly attached to a slider 81a of the front guide 81. In addition, a saddle 52a is attached to the rear guide 82 via a second spindle feed mechanism 53.

[0048] The front guide 81 and the rear guide 82 are provided in parallel to each other along the vertical direction V. As a result, the front guide 81 and the rear guide 82 regulate the saddle 52a so that it moves along the vertical direction V.

[0049] The third guide 9 is composed of a front guide 91 disposed on the rear surface of the base 31 and the central pillar 33, respectively, and a rear guide 92 disposed in the groove 3e. The front guide 91 and the rear guide 92 are, for example, linear guides. A saddle 62a is directly attached to a slider 91a of the front guide 91. In addition, a saddle 62a is attached to the rear guide 92 via a third spindle feed mechanism 63.

[0050] The front guide 91 and the rear guide 92 are provided in parallel to each other along the vertical direction V. As a result, the front guide 91 and the rear guide 92 regulate the saddle 62a so as to move along the vertical direction V.

[0051] The operation of the processing device 1 is controlled by a control unit (not shown). The control unit controls each of the components constituting the processing device 1. The control unit is composed of, for example, a CPU, a memory, and the like. The functions of the control unit may be realized by controlling using software, or may be realized by operating using hardware.

[0052] In this manner, the processing apparatus 1 continuously sends the wafer W, which is suction-held on the chuck 22 of the alignment stage S1, to the rough grinding stage S2, the medium grinding stage S3, and the fine grinding stage S4 in that order, while still being placed on the same chuck 22. Furthermore, the chuck 22 that suction-holds the wafer W can be formed to have higher rigidity than other wafer holding devices such as belt conveyors. This improves the throughput of the grinding process, and allows the wafer W to be ground with high quality.

[0053] Furthermore, since the column 3 can be formed with a larger diameter and higher rigidity than the index table 21, resonance and axial tilt of the rough grinding means 4, medium grinding means 5 and fine grinding means 6 caused by normal forces generated during grinding of the wafer W are suppressed, enabling the wafer W to be ground with high quality.

[0054] Next, a tilt mechanism of the holding means 2 will be described. As shown in Figs. 4 and 5, the holding means 2 includes two movable support parts 24 and one fixed support part 25 arranged around the chuck 22. The movable support part 24 is arranged on the outer periphery side of the index table 21 in the radial direction relative to the chuck 22. The fixed support part 25 is arranged on the inner periphery side of the index table 21 in the radial direction relative to the chuck 22.

[0055] As shown in FIG. 6, the movable support portion 24 is a differential screw mechanism including a slide block 24a, a fixed block 24b, and an adjustment screw 24c.

[0056] The slide block 24a is joined to the index table 21. A screw is drilled in the center of the slide block 24a, and the pitch of the screw of the slide block 24a is set to, for example, 1.25 mm.

[0057] The fixed block 24b is joined to a tilt table 26 on which the chuck 22 is placed. The fixed block 24b has a screw thread drilled in the center, and the pitch of the screw thread of the fixed block 24b is smaller than that of the screw thread 24d, and is set to, for example, 1.00 mm.

[0058] The adjustment screw 24c is screwed into the threaded portion of the slide block 24a and the threaded portion of the fixed block 24b. The adjustment screw 24c is rotated forward or backward by a drive motor (not shown). When the adjustment screw 24c rotates once, the chuck 22 moves up or down by an amount equal to the pitch difference (0.25 mm) between the slide block 24a and the fixed block 24b.

[0059] The fixed support portion 25 is a bolt that fastens the tilt table 26 to the index table 21 .

[0060] In this way, the movable support part 24 raises and lowers the tilt table 26 while the fixed support part 25 fixes the tilt table 26 in the vertical direction V, so that the rotation axis a2 of the chuck 22 can be tilted according to the amount of expansion and contraction of each of the two movable support parts 24. Note that the configuration of the tilt mechanism is not limited to the one using the differential screw mechanism and bolts described above, and any configuration may be used.

[0061] Next, the layout of the chuck 22 will be described with reference to the drawings.

[0062] 7(a), in a conventional processing apparatus 100, a rough grinding wheel 101, a medium grinding wheel 102, and a fine grinding wheel 103 are offset and disposed outside a chuck 104. When a tilt mechanism for tilting the chuck 104 is operated, the chuck 104 is tilted with respect to a tilt axis 106 that passes through a rotation center 105 of the chuck 104 and is parallel to two movable support parts (not shown) so that the inside of the tilt axis 106 is higher and the outside of the tilt axis 106 is lower. In addition, a perpendicular line 107 to the tilt axis 106 of the chuck 104 is disposed so as not to pass through a rotation center 109 of an index table 108 when viewed from above.

[0063] Although both ends of the processing area 110 of the rough grinding wheel 101 and the fine grinding wheel 103 are disposed on the tilt axis 106, the processing area 110 of the medium grinding wheel 102 intersects with the tilt axis 106 at the rotation center 105. That is, since the contact conditions between the wafer W and the rough grinding wheel 101 and the fine grinding wheel 103 and the contact conditions between the wafer W and the medium grinding wheel 102 are different, it is necessary to tilt the rough grinding wheel 101 and the medium grinding wheel 102 with respect to the chuck 104 so as to reproduce the contact condition between the fine grinding wheel 103 and the chuck 104.

[0064] It is also possible to arrange the rough grinding wheel 101, the medium grinding wheel 102, and the fine grinding wheel 103 in rotational symmetry so that they also contact the chuck 104 in a similar manner, as shown in Figure 7(b).

[0065] However, in such a processing apparatus 100, when the outer diameters of the rough grinding wheel 101, medium grinding wheel 102, and fine grinding wheel 103 are set to 300 mm, the distance L from the outer periphery of the medium grinding wheel 102 to the outer periphery of the fine grinding wheel 103 is approximately 925 mm, which is larger than the distance L (810 mm) from the outer periphery of the medium grinding wheel 102 to the outer periphery of the fine grinding wheel 103 in the processing apparatus 100 shown in Figure 7(a) by the amount that the medium grinding wheel 102 has moved to the left side of the page in Figure 10, resulting in a larger device size.

[0066] 8, when the tilt mechanism is operated in the processing apparatus 1 according to this embodiment, the chuck 22 tilts so that the inside of the tilt axis L1 is higher and the outside of the tilt axis L1 is lower, based on the tilt axis L1 which passes through the rotation center O1 of the chuck 22 and is parallel to the two movable support parts 24. In other words, the tilt axis L1 is at approximately the same height as the rotation center O1 on the upper surface of the chuck 22.

[0067] The chuck 22 is disposed so that a perpendicular line L2 to the tilt axis L1 passes through the rotation center O1 when viewed from above and passes through the rotation center O2 of the index table 21. That is, the chuck 22 is disposed rotationally symmetrical with respect to the rotation center O2.

[0068] The rough grinding wheel 41, the medium grinding wheel 51, and the fine grinding wheel 61 are disposed offset to the outside of the chuck 22. In addition, the rough grinding wheel 41, the medium grinding wheel 51, and the fine grinding wheel 61 contact the wafer W on an arc C having an end point P, which is one of the intersection points of the rotation center O1, the tilt axis L1, and the outer periphery of the chuck 22, as viewed from above.

[0069] Therefore, since the rough grinding wheel 41, the medium grinding wheel 51, and the fine grinding wheel 61 contact each of the chucks 22 in the same manner, if the contact state is adjusted by tilting the chuck 22 with respect to any one of the rough grinding wheel 41, the medium grinding wheel 51, and the fine grinding wheel 61, there is no need to adjust the contact state between the other grinding wheels and the chuck 22. In other words, the contact state between each grinding wheel and the chuck 22 can be appropriately adjusted without providing a mechanism for tilting the rough grinding wheel 41, the medium grinding wheel 51, and the fine grinding wheel 61.

[0070] In addition, the distance L from the outer periphery of the rough grinding wheel 41 to the outer periphery of the medium grinding wheel 51 is approximately 864 mm, which allows the device to be made more compact than a conventional processing device 100 in which the grinding wheels are arranged in rotational symmetry.

[0071] The positions of the rough grinding wheel 41, the medium grinding wheel 51 and the fine grinding wheel 61 are not limited to those shown in FIG. 8, in which each wheel is offset to the outside of the chuck 22 and the medium grinding wheel 51 and the fine grinding wheel 61 are spaced apart.

[0072] 9(a), the grinding wheels may be arranged inside the chuck 22, with the medium grinding wheel 51 and the fine medium grinding wheel 61 being close to each other. In this case, the distance from the outer periphery of the medium grinding wheel 51 to the outer periphery of the fine grinding wheel 61 is about 558 mm.

[0073] 9(b), each grinding wheel may be disposed inside the chuck 22, with the rough grinding wheel 41 and the medium grinding wheel 51 being close to each other. In this case, the distance from the outer periphery of the medium grinding wheel 51 to the outer periphery of the fine grinding wheel 61 is about 735 mm.

[0074] 9(c), each grinding wheel may be disposed outside the chuck 22, and the medium grinding wheel 51 and the fine grinding wheel 61 may be spaced apart. In this case, the distance from the outer periphery of the medium grinding wheel 51 to the outer periphery of the fine grinding wheel 61 is about 1041 mm.

[0075] The present invention can be modified in various ways without departing from the spirit of the invention, and it goes without saying that the present invention also covers such modifications. [Explanation of symbols]

[0076] 1...Processing equipment 2...holding means 21 Index table 22 Chuck 24...Movable support part 25...Fixed support part 26 Tilt table 3. Column 41 Rough grinding wheel 51 Medium grinding wheel 61...Precision grinding wheel 7. First Guide 8. Second Guide 9. Third Guide L1 Tilt axis L2: Perpendicular O1: Rotation center (of the chuck) O2: Center of rotation (of index table) W: Wafer a1: Rotation axis (of index table) a2: Rotation axis (of the chuck)

Claims

[Claim 1] A grinding apparatus for continuously grinding wafers with a plurality of grinding means, comprising: a plurality of chucks that suction-hold the wafer and are tilted by respective tilt mechanisms about tilt axes; an index table for placing the plurality of chucks and for transporting the plurality of chucks between the plurality of grinding means; Equipped with The plurality of grinding means include a rough grinding mechanism including a rough grinding wheel for grinding the wafer; a medium grinding mechanism including a medium grinding wheel for grinding the wafer; a precision grinding mechanism including a precision grinding wheel for grinding the wafer; At least the rough grinding mechanism and the medium grinding mechanism are disposed with respect to the index table so that, in a plan view, a first arc having end points at the center of rotation of the wafer and one of two intersections at which the tilt axis intersects with the outer periphery of the chuck, which is formed on the contact surface by the rough grinding wheel coming into contact with the contact surface of the wafer held by suction on the chuck, and a second arc having end points at the center of rotation and one of two intersections at which the tilt axis intersects with the outer periphery of the chuck, which is formed on the contact surface by the medium grinding wheel coming into contact with the contact surface, intersect with each other when the wafer is rotated within the contact surface to be ground; the medium grinding mechanism and the fine grinding mechanism are disposed with respect to the index table so that, in a plan view, the second arc and a third arc having end points at the center of rotation formed on the contact surface by the contact of the fine grinding wheel with the contact surface and one of two intersection points where the tilt axis intersects with the outer periphery of the chuck, intersect with each other when the wafer is rotated and ground within the contact surface. A grinding apparatus comprising:

Images