Method for manufacturing a dresser board, a dresser board, and a method for dressing a grinding wheel.

Abstract

Conventional dressing methods require preparing a dummy wafer of the same quality as the wafer to be ground and grinding the dummy wafer to prepare its condition, resulting in poor productivity. This invention provides a method for manufacturing a dresser board that can overcome this problem. [Solution] The method comprises a preparation step of preparing a semiconductor plate 20, a groove forming step of forming a plurality of grooves 100 on one surface 20a of the semiconductor plate 20, and a dressing abrasive grain embedding step of embedding dressing abrasive grains in the plurality of grooves 100 and solidifying them.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a dresser board for dressing a grinding wheel for grinding a semiconductor wafer, a dresser board for dressing a grinding wheel for grinding a semiconductor wafer, and a method for dressing a grinding wheel for grinding a semiconductor wafer.

Background Art

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

[0003] The grinding apparatus includes a chuck table for holding a wafer and grinding means rotatably mounted with a grinding wheel having a grinding wheel for grinding the wafer held on the chuck table in an annular shape, and can finish the wafer to a desired thickness (see, for example, Patent Documents 1 and 2).

[0004] In addition, the grinding end face of the grinding wheel disposed on the grinding wheel causes clogging and a decrease in grinding ability by repeatedly performing grinding processing. Therefore, at regular intervals or at an arbitrary timing, it is dressed using a dresser board in which hard abrasive grains containing diamond abrasive grains are sintered with a resin bond, and the grinding ability is regenerated.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, immediately after dressing, the protrusions of the uneven surface that make up the end face of the grinding wheel are sharp, and as such, it does not conform well to the wafer to be ground. Therefore, it is necessary to prepare a dummy wafer of the same quality as the wafer to be ground and grind the dummy wafer to prepare the condition, which results in poor productivity.

[0007] The present invention has been made in view of the above facts, and its main technical problem is to provide a method for manufacturing a dresser board, a dresser board, and a method for dressing a grinding wheel that can solve the problem of poor productivity, which arises from the fact that, conventionally, the convex parts of the irregularities that make up the end face of the grinding wheel immediately after dressing are sharp, resulting in poor contact with the wafer to be ground, and therefore it is necessary to prepare a dummy wafer of the same quality as the wafer to be ground and grind the dummy wafer to prepare the condition. [Means for solving the problem]

[0008] To solve the above-mentioned main technical problems, the present invention provides a method for manufacturing a dresser board for dressing a grinding wheel used to grind semiconductor wafers, comprising: a preparation step of preparing a semiconductor plate; a groove forming step of forming a plurality of grooves on one surface of the semiconductor plate; and a dresser grain embedding step of embedding and solidifying dresser grains in the plurality of grooves.

[0009] It is preferable that the semiconductor wafer to be ground by the grinding wheel and the semiconductor plate prepared in the preparation step are made of the same material. Furthermore, it is preferable that the grooves formed in the groove forming step are concentric, radial, dice-shaped, or a combination thereof. The semiconductor plate prepared in the preparation step is a silicon plate, and it is preferable that the dressing abrasive grains used in the dressing abrasive grain embedding step include at least one of diamond, GaN, SiC, and Al2O3. After the dressing abrasive grain embedding step, it is preferable to include a cover layer forming step in which a cover layer is formed on one side so that the dressing abrasive grains are not exposed. In the dressing abrasive grain embedding step, it is preferable to provide a predetermined step between the upper end of the groove and the upper end of the dressing abrasive grains embedded in the groove, such that the upper end of the dressing abrasive grains is lower than the upper end of the groove.

[0010] Furthermore, according to the present invention, a dresser board is provided in which dressing abrasive grains are embedded in a plurality of grooves formed on one side of a semiconductor plate.

[0011] Furthermore, the present invention provides a method for dressing a grinding wheel used to grind semiconductor wafers, comprising: a holding step of holding the other side of the dresser board described above on a chuck table; a dressing step of bringing the end face of the grinding wheel of a grinding wheel, which is provided with grinding wheels arranged in an annular shape, into contact with the dresser board held on the chuck table and dressing until the dressing abrasive grains embedded in the plurality of grooves are gone; and a finishing step of grinding the semiconductor plate constituting the dresser board with the grinding wheel after the dressing abrasive grains have been gone to adjust the condition of the end face of the grinding wheel. [Effects of the Invention]

[0012] The present invention's method for manufacturing a dresser board comprises a preparation step of preparing a semiconductor plate, a groove forming step of forming a plurality of grooves on one surface of the semiconductor plate, and a dresser grain embedding step of embedding and solidifying dresser grains in the plurality of grooves. As a result, the dresser board manufactured by the present invention makes it possible to continuously perform the dressing of the end face of a grinding wheel and the conditioning of the end face. This eliminates the need to prepare a dummy wafer of the same quality as the wafer to be ground after dressing the grinding wheel and to condition the dummy wafer by grinding it with the grinding wheel, thus resolving the conventional problem of poor productivity.

[0013] The dresser board of the present invention has dressing abrasive grains embedded in a plurality of grooves formed on one side of the semiconductor plate, making it possible to continuously perform the dressing of the end face of the grinding wheel and the conditioning of the end face. This eliminates the need to prepare a dummy wafer of the same quality as the wafer to be ground after dressing the grinding wheel and to condition the dummy wafer by grinding it with the grinding wheel, thus resolving the conventional problem of poor productivity.

[0014] The dressing method of the present invention includes a holding step of holding the other side of the dresser board on a chuck table, a dressing step of bringing the end face of a grinding wheel, which is provided with an annular grinding wheel, into contact with the dresser board held on the chuck table and dressing until the dressing abrasive grains embedded in the plurality of grooves are gone, and a finishing step of grinding the semiconductor plate constituting the dresser board with the grinding wheel after the dressing abrasive grains have been gone to adjust the condition of the end face of the grinding wheel. As a result, it is possible to perform the dressing of the end face of the grinding wheel and the adjustment of the condition of the end face in a continuous manner, eliminating the need to prepare a dummy wafer of the same quality as the wafer to be ground after dressing the grinding wheel and to adjust the condition of the dummy wafer by grinding it with the grinding wheel, thus resolving the conventional problem of poor productivity. [Brief explanation of the drawing]

[0015] [Figure 1] This is an overall perspective view of the semiconductor plate prepared by the preparation process of this embodiment. [Figure 2] (a) A perspective view showing an example of the groove forming process of this embodiment; (b) A partially enlarged cross-sectional view showing the groove shape formed by the groove forming process shown in (a); (c) A partially enlarged cross-sectional view showing another example of the groove shape formed by the groove forming process shown in (a). [Figure 3] (a) A perspective view showing another example of the groove forming process of this embodiment, and (b) A perspective view showing another pattern of grooves formed by the groove forming process shown in (a). [Figure 4] (a) A cross-sectional view showing an enlarged portion of the dresser board formed by the hard member coating process of this embodiment; (b) A cross-sectional view showing an enlarged portion of the dresser board in which a cover layer has been formed on the surface of the dresser board shown in (a); (c) A cross-sectional view in which, in the dressing abrasive grain embedding process, a predetermined step is provided between the upper end of the groove and the upper end of the dressing abrasive grain embedded in the groove, such that the upper end of the dressing abrasive grain is lower than the upper end of the groove. [Figure 5] This is an overall perspective view of a grinding apparatus suitable for carrying out the dressing method of this embodiment. [Figure 6] This is a perspective view showing an embodiment of the holding step of the dressing method according to this embodiment. [Figure 7] (a) A perspective view showing an embodiment of the dressing process in the dressing method of this embodiment, and (b) A side view showing an enlarged portion of the dressing process shown in (a) (partially shown in cross-section). [Figure 8] (a) A perspective view showing an embodiment of the finishing process in the dressing method of this embodiment, and (b) A side view showing an enlarged portion of the finishing process shown in (a) (partially shown in cross-section). [Modes for carrying out the invention]

[0016] Hereinafter, a method for manufacturing a dresser board for dressing a grinding wheel for grinding a semiconductor wafer configured based on the present invention, a dresser board suitable for dressing a grinding wheel for grinding a semiconductor wafer, and further, a method for dressing a grinding wheel implemented using the dresser board will be described.

[0017] (Preparation step) When implementing the method for manufacturing the dresser board of the present embodiment, a preparation step of preparing a semiconductor plate 20 as shown in FIG. 1 is implemented. The illustrated semiconductor plate 20 is a circular plate on which neither film formation, pattern formation, nor the like has been performed on either the front surface 20a or the back surface 20b. The semiconductor plate 20 is made of the same material as the semiconductor wafer 10 that is to be ground by a grinding wheel 4d to be dressed in a grinding apparatus 1 (to be described in detail later) shown in FIG. 5. In the present embodiment, since the wafer 10 ground by the grinding wheel 4d of the grinding apparatus 1 is a silicon (Si) wafer, the semiconductor plate 20 is also made of silicon. The semiconductor plate 20 has a diameter, for example, 200 mm, which is held by the chuck table 3 of the grinding apparatus 1, and a thickness, for example, 1 mm.

[0018] (Groove formation step) If the above-described semiconductor plate 20 is prepared, a groove formation step of forming a plurality of grooves on one surface (for example, the front surface 20a) of the semiconductor plate 20 is implemented. A method for forming the plurality of grooves can be adopted from well-known methods. Also, the pattern shape formed by the plurality of grooves can be arbitrarily set, and for example, it can be formed in any of a concentric circle shape, a radial shape, a grid shape, or a combination thereof.

[0019] FIG. 2 shows an example of forming a plurality of ring-shaped grooves 100 on the front surface 20a of the semiconductor plate 20 by a laser processing apparatus 30 (only a part is shown) to form a concentric pattern.

[0020] The laser processing apparatus 30 includes a chuck table 32 for holding a semiconductor plate 20, and a laser beam irradiation means 34 for irradiating the semiconductor plate 20 held by the chuck table 32 with a laser beam LB. The laser processing apparatus 30 also includes an X-axis moving means (not shown) for moving the chuck table 32 in the X-axis direction indicated by arrow X in the figure, a Y-axis moving means (not shown) for moving the chuck table 32 in the Y-axis direction indicated by arrow Y in the figure, which is perpendicular to the X-axis direction, and a rotational drive means (not shown) for rotating the chuck table 32.

[0021] The semiconductor plate 20, transported to the laser processing apparatus 30, is placed on the chuck table 32 with its surface 20a facing upwards and held in place by suction. The semiconductor plate 20 held on the chuck table 32 is aligned by an alignment means (not shown) provided in the laser processing apparatus 30, and the center position and the outer periphery position of the semiconductor plate 20 are detected.

[0022] Based on the position information detected by the alignment process described above, the X-axis moving means and Y-axis moving means are operated to position the focuser 36 of the laser beam irradiation means 34 at a predetermined distance from the center of the semiconductor plate 20 to the processing start position. Then, the focal point of the laser beam LB, which has a wavelength absorbed by the semiconductor plate 20, is positioned on the surface 20a at a predetermined position from the center of the semiconductor plate 20 and irradiated, and the chuck table 32 is rotated in the direction indicated by arrow R1 to perform ablation processing on the surface 20a of the semiconductor plate 20 to form a ring-shaped groove 100. If the width of the ring-shaped groove 100 to be formed is to be larger than the spot diameter at the focal point of the laser beam LB, the position of the focal point is finely adjusted in the Y-axis direction and the laser beam LB is irradiated while rotating the chuck table 32 to perform the laser processing described above so that a ring-shaped groove 100 of the desired width is formed.

[0023] Once a ring-shaped groove 100 is formed at a predetermined position from the center of the semiconductor plate 20, the semiconductor plate 20 is indexed and fed in the Y-axis direction at predetermined intervals, and the focal point of the laser beam LB is positioned outside the area on the semiconductor plate 20 where the groove 100 has already been formed and irradiated, while the chuck table 32 is rotated in the direction indicated by arrow R1 to form a groove 100 that is concentric with the first groove 100 formed.

[0024] Using the same procedure as the laser processing described above, the focal point of the laser beam LB is positioned at predetermined intervals outside the area where the grooves 100 are formed on the semiconductor plate 20 and irradiated, and the chuck table 32 is rotated in the direction indicated by arrow R1, so that a plurality of ring-shaped grooves 100 are formed over the entire surface 20a of the semiconductor plate 20, as shown in Figure 2(a), thereby forming a concentric pattern.

[0025] As shown in Figure 2(b), the groove 100 described above is formed with, for example, a depth of 0.2 mm and a width of 5 mm. The distance between two adjacent grooves 100 is set to, for example, 20 mm. Note that in Figure 2(b), for explanatory purposes, the thickness of the semiconductor plate 20, the depth and width of the groove 100, and the distance between two adjacent grooves 100 are shown in dimensional ratios that differ from the actual dimensional ratios. Also, although the cross-sectional shape of the groove 100 of the semiconductor plate 20 shown in Figure 2(b) is depicted as a regular concave shape, it is not necessarily required to be this shape. For example, the groove 100' formed on the surface 20a' of the semiconductor plate 20' shown in Figure 2(c) may have a roughly V-shaped cross-section.

[0026] Figure 3(a) shows an embodiment of a groove formation process in which, instead of forming multiple ring-shaped grooves 100 on the surface 20a of the semiconductor plate 20 with the laser processing apparatus 30 described above, a cutting apparatus 40 (only a part is shown) is used to form multiple linear grooves 110 on the surface 20a of the semiconductor plate 20, thereby forming a dice-like pattern.

[0027] The cutting apparatus 40 comprises a chuck table 42 for suction-holding a semiconductor plate 20, and a cutting means 44 for cutting the semiconductor plate 20 held by the chuck table 42. The chuck table 42 is configured to be rotatable and is equipped with an X-axis moving means (not shown) for machining feed of the chuck table in the direction indicated by arrow X in the figure. The cutting means 44 comprises a spindle 46 arranged and held in the Y-axis direction indicated by arrow Y in the figure, and an annular cutting blade 48 held at the tip of the spindle 46, and is equipped with a Y-axis moving means (not shown) for indexing feed of the cutting blade 48 in the Y-axis direction. The spindle 46 is rotationally driven by a spindle motor (not shown).

[0028] In forming a dice-like pattern with the multiple grooves 110 described above, first, the semiconductor plate 20 is placed on the chuck table 42 of the cutting device 40 with its surface 20a facing upwards and held in place by suction. Next, the semiconductor plate 20 is imaged by an alignment means (not shown) to detect the planned machining positions of the grooves 110 that will form the dice-like pattern. Then, the planned machining positions along a predetermined direction are aligned with the X-axis direction, and alignment is performed with the cutting blade 48.

[0029] A cutting blade 48, rotated at high speed in the direction indicated by arrow R2, is positioned at the machining location aligned with the X-axis direction, and a cut is made from the surface 20a side, while the chuck table 42 is machined in the X-axis direction to form a groove 110. Furthermore, the Y-axis moving means is activated to index and feed the cutting blade 48 of the cutting means 44 to a machining location adjacent to the machining location where the groove 110 has been formed, where no groove 110 has been formed, and a groove 110 is formed in the same manner as above. By repeating these steps, multiple grooves 110 are formed along all machining locations along the X-axis direction. Next, the chuck table 42 is rotated 90 degrees to align the direction perpendicular to the direction in which the grooves 110 were previously formed with the X-axis direction, and the above cutting process is performed on all newly aligned machining locations along the X-axis direction to form grooves 110 along the machining locations that form the dice-shaped pattern set on the surface 20a of the semiconductor plate 20. As a result, a dice-like pattern is formed on the surface 20a of the semiconductor plate 20 by a plurality of grooves 110 as shown in Figure 3(a). It is preferable that the plurality of grooves 110 formed by this embodiment are formed with the depth, width, and spacing shown in Figure 2(b) above.

[0030] Furthermore, in another groove-forming process using the cutting device 40 described above, as shown in Figure 3(b), a plurality of grooves 120 passing through the center O may be formed on the surface 20a of the semiconductor plate 20 to form a radial pattern. Preferably, these grooves 120 are formed with the same depth and width as the grooves 100 and 110 described above, and preferably the average distance between two adjacent grooves 120 is the same as the distance between grooves 100 and 110 described above.

[0031] The concentric, dice-shaped, and radial patterns described above are not limited to being formed individually, but may be combined. Furthermore, in the above embodiment, the grooves 100 forming the concentric pattern were formed by a laser processing device 30, and the grooves 110 forming the dice-shaped pattern and the grooves 120 forming the radial pattern were formed by a cutting device 40. However, the groove formation process of the present invention is not limited to this, and the grooves 100 constituting the concentric pattern may be formed by a cutting device 40, and the grooves 110 constituting the dice-shaped pattern and the grooves 120 constituting the radial pattern may be formed by a laser processing device 30. However, when forming curved grooves, it is preferable to use a laser processing device 30.

[0032] (Abrasive grain embedding process) As described above, once the groove formation process is carried out, a dress abrasive grain embedding process is performed in which dress abrasive grains 50 are embedded in the plurality of grooves (grooves 100 in the illustrated embodiment) formed in the semiconductor plate 20, as shown in Figure 4(a), and solidified. The dress abrasive grains 50 to be embedded here are, for example, hard abrasive grains containing diamond, and these hard abrasive grains can be solidified by kneading them with a resin bond, embedding them in the plurality of grooves as shown in Figure 4(a), and then sintering them. These hard abrasive grains are at least harder than the material constituting the semiconductor plate 20, and when using a semiconductor plate 20 made of silicon (Si) as in this embodiment, in addition to the diamond described above, for example, GaN, SiC, Al2O3, or a combination thereof can be selected as hard abrasive grains.

[0033] As described above, a dresser board 20A is formed in which dressing abrasive grains 50 are embedded and solidified in a plurality of grooves 100 formed on one side of the semiconductor plate 20, and the method for manufacturing the dresser board of this embodiment is completed.

[0034] A dressing method can be implemented to dress a grinding wheel by transporting the dresser board 20A, which is constructed according to the present invention, to the grinding apparatus 1 (see Figure 5), which will be described later. In this case, the dresser board may be transported to the chuck table 3 of the grinding apparatus 1 by a suction member of a transport means (not shown in the figure). When the suction member comes into contact with the dressing abrasive grains 50 exposed on the surface 20a of the dresser board 20A, the suction member may be scratched, which may affect the subsequent transport operation.

[0035] (Cover layer formation process) To address the above-mentioned problems, after performing the dressing abrasive grain embedding process described above to form the dresser board 20A, a cover layer formation process may be performed as needed to form a dresser board 20B in which a cover layer 60 is provided to cover one side (surface 20a) of the semiconductor plate 20 in which the dressing abrasive grains 50 are embedded, as shown in Figure 4(b).

[0036] The cover layer 60 disposed on the dresser board 20B shown in Figure 4(b) is, for example, a silicon wafer with a thickness of 0.1 mm. Preferably, the 0.1 mm thick silicon wafer is bonded to one surface (surface 20a) of the dresser board 20A via an oxide film by the dressing abrasive grain embedding process described above, and heat treatment is performed to increase the bonding strength to bond by siloxane bonds. As a result, the dressing abrasive grains 50 are covered by the cover layer 60, preventing the suction member of the transport means from directly contacting the dressing abrasive grains 50 exposed on the surface 20a of the dresser board 20A, thus avoiding the problem of the suction member being damaged.

[0037] The cover layer 60 described above is formed as thinly as possible so as not to interfere with the dressing process in the dressing method described later. Furthermore, the placement of the cover layer 60 is not necessarily limited to bonding the silicon wafers described above. For example, the material that will become the cover layer 60 may be deposited on the surface 20a of the dresser board 20A by sputtering or vapor deposition to form a cover layer 60 that covers the dressing abrasive grains 50. The material deposited on one side of the dresser board 20A is preferably silicon atoms, but it may also be other materials (e.g., alumina) that do not interfere with the dressing process in the dressing method described later.

[0038] In the dresser board 20A described above, if the suction member of a transport means (not shown) comes into contact with the dressing abrasive grains 50 exposed on the surface 20a, the suction member may be damaged, potentially affecting subsequent transport operations. This can be addressed by using a dresser board 20C, such as the one shown in Figure 4(c). The illustrated dresser board 20C is formed in the semiconductor plate 20 during the dressing abrasive grain embedding process described above, by embedding the dressing abrasive grains 50' in a plurality of grooves (grooves 100 in the illustrated embodiment) as shown and solidifying them. The dressing abrasive grains 50' embedded here are, for example, hard abrasive grains containing diamond. Hard abrasive grains similar to those of the dressing abrasive grains 50 of the dresser board 20A described above can be mixed with a resin bond and embedded in the plurality of grooves 100 as shown in Figure 4(c), and then solidified by sintering. Here, a predetermined step is provided between the upper end of the groove 100 in the dresser board 20C, i.e., the surface 20a of the dresser board 20C, and the upper end 50'a of the dressing abrasive grains 50' embedded in the groove 100, such that the upper end 50'a of the embedded dressing abrasive grains 50' is lower than the upper end of the groove 100 in the dresser board 20C. A step of about 0.1 mm is preferred. This prevents the problem of the suction member not contacting the dressing abrasive grains 50' of the dresser board 20C, even when the dresser board 20C is picked up by a suction member of a transport means (not shown) and transported to the chuck table 3 of the grinding device 1, causing damage to the suction member and affecting subsequent transport operations. The following description will explain a method for dressing a grinding wheel using the dresser board 20A described based on Figure 4(a).

[0039] Figure 5 shows a grinding apparatus 1 on which the dressing method of this embodiment is carried out. The grinding apparatus 1 comprises an apparatus housing 2 and includes, for example, a chuck table 3 for holding a silicon (Si) wafer 10 on which protective tape T is attached to the surface, a grinding means 4 for grinding the back surface of the wafer 10 held on the chuck table 3, and a feed means 5 for feeding the grinding means 4 in the Z-axis direction (vertical direction).

[0040] As can be seen from Figure 5, the chuck table 3 comprises a holding surface 3a for suction holding of the wafer 10, and a frame 3b that supports and surrounds the holding surface 3a. The holding surface 3a is made of a porous material that allows for airflow, and a suction means (not shown) is connected to the frame 3b. By operating the suction means, a negative pressure is generated on the holding surface 3a, allowing the wafer 10 to be held in place by suction.

[0041] The chuck table 3 is configured to be rotatable by a rotary drive mechanism (not shown) and can be moved by a Y-axis moving mechanism (not shown) housed inside the apparatus housing 2 to any position in the Y-axis direction indicated by arrow Y in the figure, for example, an loading / unloading position on the front side of the figure where wafers 10 are loaded and unloaded, and a grinding position where grinding is performed directly below the grinding mechanism 4.

[0042] The grinding means 4 comprises at least a rotating shaft 4a, a wheel mount 4b disposed at the lower end of the rotating shaft 4a, a grinding wheel 4c mounted on the wheel mount 4b, a plurality of grinding wheels 4d arranged in an annular pattern on the lower surface of the grinding wheel 4c, an electric motor 4g for rotating the rotating shaft 4a, a support part 4e for supporting the grinding means 4, and a Z-axis movable base 4f supported on the vertical wall 2a of the device housing 2 together with the support part 4e so as to be able to move up and down in the Z-axis direction. The grinding wheel 4d is made of a grinding wheel suitable for grinding the silicon (Si) wafer 10 described above. The feeding means 5 converts the rotational motion of the pulse motor 5a into linear motion via a ball screw 5b rotated by the pulse motor 5a and transmits it to the Z-axis movable base 4f, thereby moving the grinding means 4 to any position in the Z-axis direction (vertical direction).

[0043] Grinding water L is supplied from a grinding water supply source (not shown) to the upper end 4a' of the rotating shaft 4a, and then supplied via the inside of the rotating shaft 4a to the wafer 10 held by the chuck table 3 and the grinding wheel 4d that grinds the wafer 10. The grinding apparatus 1 is equipped with control means (not shown), and each of the above-mentioned operating parts is controlled by a control signal instructed by the control means.

[0044] The grinding apparatus 1 has a configuration that is generally as described above, and the method for dressing the grinding wheel 4d after grinding a predetermined number (for example, 20) wafers 10 will be described below.

[0045] (holding process) A dresser board 20A manufactured by the dresser board manufacturing method described above is prepared, and as shown in Figure 6, the other side of the dresser board 20A (the back side 20b where the groove 100 is not formed) is placed on the holding surface 3a of the chuck table 3, and a suction means (not shown) is activated to generate negative pressure on the holding surface 3a to hold the dresser board 20A in place by suction.

[0046] (Dressing process) Once the dresser board 20A is held on the chuck table 3 by the holding process described above, the Y-axis moving means described above is activated to move the chuck table 3 to the grinding position directly below the grinding means 4, as shown in Figure 7(a). Next, the rotation axis 4a of the grinding means 4 is rotated at, for example, 6000 rpm in the direction indicated by arrow R3 in the figure, while the chuck table 3 is rotated at, for example, 300 rpm in the direction indicated by arrow R4. Furthermore, the feed means 5 described above is activated to lower the grinding means 4 in the direction indicated by arrow R5, bringing the grinding wheel 4d into contact with the dresser board 20A, and the grinding wheel 4c is fed downward at, for example, a speed of 1.0 μm / second. At this time, it is preferable to supply grinding water L supplied by a grinding water supply means (not shown) onto the surface 20a of the dresser board 20A via the rotation axis 4a. Then, as shown in a magnified view in Figure 7(b), the end face 4d' of the grinding wheel 4d is brought into contact with the dressing abrasive grains 50 embedded in the multiple grooves 100 of the dresser board 20A, thereby dressing the end face 4d' of the grinding wheel 4d. At this time, the thickness of the dresser board 20A is detected by a non-contact or contact-type thickness detection means (not shown), and this dressing process is carried out until the thickness is such that the dressing abrasive grains 50 embedded in the multiple grooves 100 are gone.

[0047] (Finishing process) By performing the dressing process described above, as shown in Figure 8(a), the grooves 100 in which the dressing abrasive grains 50 are embedded disappear from the surface 20a of the dresser board 20A, and the entire surface becomes silicon of the same quality as the wafer 10 that is ground by the grinding wheel 4d. At this point, the operation of the grinding means 4 and the feeding means 5 in the dressing process described above is continued for a predetermined time, and the grinding means 4 is fed in the direction indicated by the arrow R5. As a result, as shown in Figure 8(b), the surface 20a of the semiconductor plate 20 constituting the dresser board 20A is ground with the grinding wheel 4d, and the condition of the end face 4d' of the grinding wheel 4d is adjusted. With this, the finishing process of this embodiment is completed, and the dressing method of this embodiment is completed. The dresser board 20A is formed assuming a thickness to be ground by the dressing and finishing processes described above, and is discarded after the dressing and finishing processes are performed.

[0048] According to the above-described method for manufacturing a dresser board, the dresser board, and the dressing method performed using the dresser board, the dressing of the end face of the grinding wheel and the conditioning of the end face are performed continuously on a single dresser board 20A. After dressing the grinding wheel, it is no longer necessary to prepare a dummy wafer of the same quality as the wafer to be ground and condition the dummy wafer by grinding it with the grinding wheel, thus resolving the conventional problem of poor productivity.

[0049] Furthermore, in the above-described embodiment, an example was shown in which a dressing method constructed according to the present invention is carried out using a dresser board 20A constructed by forming a plurality of grooves 100 on one surface (surface 20a) of a semiconductor plate 20 to form a concentric circular pattern. However, the same effects as in the above-described embodiment can be obtained even with a dresser board in which a dice-like pattern is formed by a plurality of grooves 110 as shown in Figure 3(a) and dressing abrasive grains 50 are embedded in the plurality of grooves 110, or with a dresser board in which a radial pattern is formed by a plurality of grooves 120 as shown in Figure 3(b) and dressing abrasive grains 50 are embedded in the plurality of grooves 120.

[0050] Furthermore, as explained with reference to Figure 4(b), when the dressing method is performed using a dresser board 20B obtained by performing a cover layer formation step to form a cover layer 60 on one side so that the dressed abrasive grains 50 are not exposed after the dressed abrasive grain embedding step, direct contact between the suction member of the transport means (not shown) and the dressed abrasive grains 50 is avoided, thus avoiding the problem of damage to the suction member. Moreover, when the dressing method is performed using a dresser board 20B equipped with the cover layer 60, the cover layer 60 is removed quickly after the start of the dressing step, and the dressing step and finishing step are performed continuously, thereby obtaining the same effects as in the above embodiment.

[0051] Furthermore, as explained with reference to Figure 4(c), in the dressing abrasive grain embedding step described above, if a predetermined step is provided between the upper end of the groove 100 (surface 20a of the dresser board 20C) and the upper end 50'a of the dressing abrasive grains 50' embedded in the groove 100, and the dressing abrasive grains 50' are formed so that they are not exposed to the surface 20a of the dresser board 20C, then direct contact between the suction member of the transport means (not shown) and the dressing abrasive grains 50' is avoided, thus avoiding the problem of damage to the suction member. Moreover, when the dressing method described above is performed using the dresser board 20C, after the start of the dressing step, the surface 20a of the dresser board 20C is ground and removed, the dressing abrasive grains 50' are exposed to the surface 20a, and the dressing step and finishing step described above are carried out continuously, thereby obtaining the same effects as in the embodiment described above. [Explanation of symbols]

[0052] 1: Grinding device 2: Device housing 3: Chuck Table 3a: Holding surface 3b: Frame 4: Grinding method 4a: Rotation axis 4b: Wheel mount 4c: Grinding Wheel 4d: Grinding wheel 4d': End face 4e: Support part 4f: Z-axis moving base 4g: Electric motor 5: Feeding method 10: Semiconductor wafers 20: Semiconductor plate 20a: Surface (one side) 20b: Reverse side (the other side) 20A, 20B, 20C: Dresserboard 30: Laser processing equipment 32: Chuck Table 34: Laser beam irradiation means 36: Light concentrator 40: Cutting equipment 42: Chuck Table 44:Cutting means 46: Spindle 48: Cutting blade 50: Dressing abrasive grains 60: Cover layer 100, 110, 120: groove L: Grinding water

Claims

1. A method for manufacturing a dresser board for dressing a grinding wheel used to grind semiconductor wafers, Preparation process for preparing semiconductor plates, A groove forming process in which multiple grooves are formed on one side of a semiconductor plate, A dressing abrasive grain embedding process in which dressing abrasive grains are embedded in multiple grooves and solidified, A method for manufacturing a dresser board comprising the components mentioned above.

2. A method for manufacturing a dresser board according to claim 1, wherein the semiconductor wafer to be ground by the grinding wheel and the semiconductor plate prepared in the preparation step are formed of the same material.

3. A method for manufacturing a dresser board according to claim 1, wherein the grooves formed in the groove forming step are concentric, radial, dice-shaped, or a combination thereof.

4. The semiconductor plate prepared in the preparation step is a silicon plate, and the dressing abrasive grains used in the dressing abrasive grain embedding step are diamond, GaN, SiC, and Al. ２ O ３ A method for manufacturing a dresser board according to claim 1 or 2, comprising at least one of the above.

5. A method for manufacturing a dresser board according to claim 1, comprising a cover layer forming step, after the dress abrasive grain embedding step, in which a cover layer is formed on one side so that the dress abrasive grains are not exposed.

6. In the dressing abrasive grain embedding process, A method for manufacturing a dresser board according to claim 1, wherein a predetermined step is provided between the upper end of the groove and the upper end of the dressing abrasive grain embedded in the groove, such that the upper end of the dressing abrasive grain is lower than the upper end of the groove.

7. A dresser board in which dressing abrasive grains are embedded in multiple grooves formed on one side of a semiconductor plate.

8. A method for dressing a grinding wheel used to grind semiconductor wafers, A holding step of holding the other side of the dresser board according to claim 7 on a chuck table, A dressing step in which the end face of the grinding wheel of a grinding wheel, which is provided with a grinding wheel in an annular shape, is brought into contact with a dresser board held on the chuck table and dressed until the dressing abrasive grains embedded in the plurality of grooves are gone, After the dressing abrasive grains are used up, a finishing step is performed in which the semiconductor plate constituting the dresser board is ground with a grinding wheel to adjust the condition of the end surface of the grinding wheel, A method for dressing grinding wheels, including those containing [unclear].

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