Polishing pad dresser and dressing device

Abstract

Provided is a polishing pad dresser comprising: a dresser body with a circular metal base and a chip located on the metal base; and an elastic member located on the side of the metal base opposite from the chip, wherein the chip has a plurality of protrusions which protrude out toward the side opposite from the metal base and which a surface is formed by means of a diamond film. Also provided is a dressing device comprising: the abovementioned polishing pad dresser located above a polishing pad; and a rotatable dress head on which the polishing pad dresser is mounted, wherein the polishing pad dresser is mounted on the dress head such that the elastic member is located between the dress head and the metal base.

Description

Polishing pad dresser and dressing device

[0001] The present disclosure relates to a polishing pad dresser and a dressing device for dressing a polishing pad of a polishing device that polishes semiconductor wafers and the like.

[0002] Patent Document 1 describes a dresser (conditioner) that dresses (conditions) the polishing pad of a polishing apparatus. This dresser has a base metal such as stainless steel and multiple chips made of Si wafers attached to the base metal, and the chips are configured by forming a diamond film on multiple protrusions by a CVD (Chemical Vapor Deposition) method. A dresser using a chip with a diamond film formed on multiple protrusions by a CVD method is called a CVD dresser.

[0003] JP 2018-032745 A

[0004] In a CVD dresser, the tips of the multiple protrusions are sharper and of uniform height than diamond abrasive grains. Therefore, if the resistance between the tip and the polishing pad increases during dressing, the CVD dresser is prone to vibrations of about 0 to 1 kHz (hereinafter also referred to as "chatter vibrations"). If such vibrations occur, stable dressing cannot be performed and the tip protrusions may break. Note that chatter vibrations rarely occur in electroplated tips in which multiple diamond abrasive grains are fixed by electrodeposition, and in bonded tips in which multiple diamond abrasive grains are fixed by a bond layer (metal bond, vitreous bond, resin bond, etc.).

[0005] Therefore, an object of the present disclosure is to provide a polishing pad dresser and a dressing device that can suppress vibrations during dressing.

[0006] [1] A polishing pad dresser according to the present disclosure includes a dresser body having an annular base metal and a tip disposed on the base metal, and an elastic member disposed on the base metal opposite the tip, and the tip has a plurality of protrusions protruding on the side opposite the base metal and having a surface formed with a diamond film.

[0007] This polishing pad dresser can dress a polishing pad by attaching a base metal to the dressing head of a dressing device and rotating the dressing head. Here, the polishing pad dresser has a tip that protrudes from the side opposite the base metal and has multiple protrusions with a diamond film on its surface. Therefore, if the resistance between the tip and the polishing pad increases during dressing, chatter vibrations are likely to occur. However, because an elastic member is disposed on the side of the base metal opposite the tip, the elastic member is disposed between the dressing head and the base metal, and chatter vibrations are damped by the elastic member. This allows chatter vibrations to be suppressed during dressing.

[0008] [2] In the polishing pad dresser described in [1], the Shore A hardness of the elastic member may be 45 or more and 95 or less. In this polishing pad dresser, since the Shore A hardness of the elastic member is 45 or more and 95 or less, the polishing pad dresser can be stably attached to the dressing head and chatter vibration can be suppressed.

[0009] [3] In the polishing pad dresser according to [1] or [2], the elastic member may be made of rubber. In this polishing pad dresser, chatter vibrations can be appropriately suppressed because the elastic member is made of rubber.

[0010] [4] In the polishing pad dresser according to any one of [1] to [3], the tip has a substrate and a diamond film formed on the substrate, and the substrate may contain silicon. In this polishing pad dresser, since the substrate contains silicon, the multiple protrusions of the tip can be easily formed.

[0011] [5] In the polishing pad dresser according to any one of [1] to [4], the tips of the plurality of protrusions may be formed at an acute angle. In this polishing pad dresser, the tips of the plurality of protrusions are formed at an acute angle, which makes it easy for chatter vibrations to occur when the resistance between the tip and the polishing pad increases during dressing of the polishing pad. However, the elastic member disposed on the side of the base metal opposite the tip can suppress chatter vibrations.

[0012] [6] In the polishing pad dresser according to any one of [1] to [5], the variation in height of the plurality of protrusions relative to the base metal may be 0 mm or more and 0.3 mm or less. In this polishing pad dresser, the variation in height of the plurality of protrusions relative to the base metal is 0 mm or more and 0.3 mm or less. Because this polishing pad dresser has a structure in which chatter vibrations are likely to occur if the resistance between the tip and the polishing pad increases during dressing of the polishing pad. However, because an elastic member is disposed on the side of the base metal opposite the tip, chatter vibrations can be suppressed.

[0013] [7] In the polishing pad dresser according to any one of [1] to [6], the elastic member may extend in the circumferential direction of the base metal. In this polishing pad dresser, the elastic member extends in the circumferential direction of the base metal, so that the polishing pad dresser can be stably attached to the dressing head and chatter vibrations can be effectively suppressed.

[0014] [8] In the polishing pad dresser according to any one of [1] to [7], the elastic member may be formed in an annular shape. In this polishing pad dresser, the elastic member is formed in an annular shape, which allows the polishing pad dresser to be stably attached to the dressing head and effectively suppresses chatter vibrations.

[0015] [9] In the polishing pad dresser according to any one of [1] to [8], a groove into which an elastic member is fitted may be formed on the mounting surface of the base metal opposite the tip. In this polishing pad dresser, the groove into which the elastic member is fitted is formed on the mounting surface of the base metal opposite the tip. By fitting the elastic member into the groove, it is possible to easily position the elastic member relative to the base metal and also to easily attach the elastic member to the base metal.

[0016]

[10] In the polishing pad dresser described in [9], the thickness of the elastic member may be greater than the depth of the groove. In this polishing pad dresser, the thickness of the elastic member is greater than the depth of the groove, so that chatter vibrations can be suppressed by the elastic member even when the elastic member is fitted to the bottom of the groove.

[0017]

[11] In the polishing pad dresser according to [9] or

[10] , when the elastic member is fitted into the groove, the protruding length of the elastic member from the base metal in the thickness direction of the base metal may be 0.1 mm or more and 3 mm or less. In this polishing pad dresser, when the elastic member is fitted into the groove, the protruding length of the elastic member from the base metal in the thickness direction of the base metal is 0.1 mm or more and 3 mm or less, so that the polishing pad dresser can be stably attached to the dressing head and chatter vibration can be effectively suppressed.

[0018]

[12] In the polishing pad dresser according to any one of [9] to

[11] , the groove may be formed in the peripheral portion of the mounting surface. In this polishing pad dresser, the groove is formed in the peripheral portion of the mounting surface, so that an elastic member can be easily fitted into the groove. Furthermore, by fitting the elastic member into the groove, it is possible to arrange the elastic member over a wider area, stably attach the polishing pad dresser to the dressing head, and effectively suppress chatter vibrations.

[0019]

[13] In the polishing pad dresser according to any one of [9] to

[11] , the groove may be formed concentrically with the mounting surface at a position spaced from the peripheral edge of the mounting surface. In this polishing pad dresser, the groove is formed concentrically with the mounting surface at a position spaced from the peripheral edge of the mounting surface, thereby preventing the elastic member fitted in the groove from falling out of the groove. Furthermore, fitting the elastic member in the groove allows the polishing pad dresser to be stably attached to the dressing head and effectively suppresses chatter vibrations.

[0020]

[14] In the polishing pad dresser according to any one of [1] to

[13] , the elastic member may be arranged to cover only a portion of the mounting surface of the base metal opposite the tip. In this polishing pad dresser, the elastic member is arranged to cover only a portion of the mounting surface of the base metal opposite the tip, thereby forming a gap between the dressing head and the base metal. This makes it easier for the elastic member to elastically expand and contract, thereby effectively suppressing chatter vibrations.

[0021]

[15] A dressing device according to the present disclosure includes the polishing pad dresser according to any one of [1] to

[14] and a rotatable dressing head to which the polishing pad dresser is attached, the polishing pad dresser being attached to the dressing head such that an elastic member is disposed between the dressing head and the base metal. Since this dressing device includes the polishing pad dresser described above, chatter vibrations during dressing can be suppressed.

[0022]

[16] In the dressing device according to

[15] , a gap may be formed between the dressing head and the base metal. In this dressing device, a gap is formed between the dressing head and the base metal. This makes it easier for the elastic member to elastically expand and contract, thereby effectively suppressing chatter vibrations.

[0023] According to the present disclosure, vibrations during dressing can be suppressed.

[0024] FIG. 1 is a schematic perspective view showing a polishing apparatus of this embodiment. FIG. 2 is a schematic cross-sectional view showing a dressing apparatus of this embodiment. FIG. 3 is a schematic bottom view showing a polishing pad dresser of this embodiment. FIG. 4 is a schematic plan view showing a polishing pad dresser of this embodiment. FIG. 5 is a cross-sectional view taken along line V-V in FIG. 3. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 3. FIGS. 7(a), 7(b), and 7(c) are cross-sectional views for explaining an example of a manufacturing method of a dresser body. FIG. 8 is a schematic plan view showing a polishing pad dresser of a modified example. FIG. 9 is a schematic plan view showing a polishing pad dresser of a modified example. FIG. 10 is a schematic plan view showing a polishing pad dresser of a modified example. FIG. 11 is an SEM photograph of the working surface of a tip of an example and a comparative example. FIG. 12 is an SEM photograph of the working surface of a tip of an example and a comparative example. FIG. 13 is a graph showing the results of Examples 1 to 3 and Comparative Examples 1 to 3.

[0025] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, the same or equivalent elements will be denoted by the same reference numerals, and redundant description will be omitted.

[0026] FIG. 1 is a schematic perspective view showing a polishing apparatus according to the present embodiment. As shown in FIG. 1, the polishing apparatus 1 according to the present embodiment is an apparatus for polishing semiconductor wafers. The polishing apparatus 1 includes a rotatable turntable 2, a polishing pad 3 disposed on the turntable 2 and rotating integrally therewith, a rotatable polishing head 4 disposed above the polishing pad 3, a nozzle 5 disposed above the polishing pad 3 for supplying slurry or pure water onto the polishing pad 3, and a dressing device 6 for dressing the polishing pad 3. The turntable 2 and the polishing head 4 are each rotated by a driving device (not shown). In the polishing apparatus 1, a semiconductor wafer is attached to the lower end of the polishing head 4, the turntable 2 and the polishing head 4 are rotated, the nozzle 5 supplies slurry or pure water onto the polishing pad 3, and the polishing head 4 presses the semiconductor wafer against the polishing pad 3 with a predetermined pressure, thereby polishing the semiconductor wafer.

[0027] 2 is a schematic cross-sectional view showing the dressing apparatus of this embodiment. As shown in Figures 1 and 2, the dressing apparatus 6 of this embodiment includes a rotatable dressing head 7 disposed above the polishing pad 3, and a polishing pad dresser 10 attached to the lower end of the dressing head 7. The dressing head 7 is rotated by a driving device (not shown).

[0028] FIG. 3 is a schematic bottom view showing the polishing pad dresser of this embodiment. FIG. 4 is a schematic plan view showing the polishing pad dresser of this embodiment. FIG. 5 is a cross-sectional view taken along line V-V in FIG. 3. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 3. As shown in FIGS. 2 to 6, the polishing pad dresser 10 of this embodiment includes a dresser body 11 and an elastic member 12. The dresser body 11 includes an annular base metal 13 and a plurality of chips 14 arranged on the base metal 13. The base metal 13 is made of stainless steel (SUS) or the like.

[0029] The surface of the base metal 13 opposite to the multiple chips 14 is referred to as the mounting surface 13a. A groove 13b into which the elastic member 12 is fitted is formed on the mounting surface 13a. The groove 13b is formed on the periphery of the mounting surface 13a. In other words, the groove 13b is formed around the entire periphery of the mounting surface 13a so as to be concentric with the mounting surface 13a.

[0030] Each of the multiple tips 14 (hereinafter simply referred to as "tip 14") is a member that dresses the polishing pad 3. The surface of the tip 14 opposite the base metal 13 is called the working surface 14a. The working surface 14a is the surface that dresses the polishing pad 3. The tip 14 is attached to the base metal 13. The tip 14 can be attached to the base metal 13 by, for example, adhesive bonding. The tip 14 has multiple protrusions 15 that protrude on the side opposite the base metal 13 and have a surface formed with a diamond film 17. The multiple protrusions 15 are parts that dress the polishing pad 3 and are formed on the working surface 14a. The shape of each of the multiple protrusions 15 is not particularly limited, but can be, for example, a pointed shape such as a cone or a polygonal pyramid.

[0031] The chip 14 has a substrate 16 and a diamond film 17 formed on the surface of the substrate 16 opposite to the base metal 13. The substrate 16 is formed from a silicon-containing material such as silicon (Si) or silicon carbide (SiC). The substrate 16 has a plurality of protrusions protruding on the side opposite to the base metal 13. The plurality of protrusions on the substrate 16 are the portions of the plurality of protrusions 15 of the chip 14 excluding the diamond film 17. The diamond film 17 is formed on the surface of the substrate 16 opposite to the base metal 13. Therefore, the diamond film 17 is also formed on the plurality of protrusions of the substrate 16. The diamond film 17 is formed on the substrate 16 by a CVD method.

[0032] An example of a method for manufacturing the dresser body 11 will now be described with reference to Fig. 7. Fig. 7(a), Fig. 7(b), and Fig. 7(c) are cross-sectional views for explaining an example of a method for manufacturing the dresser body.

[0033] First, as shown in FIG. 7( a), a substrate 16 having a plurality of protrusions is prepared. The substrate 16 having a plurality of protrusions can be prepared, for example, by the method described in Patent Document 1 (JP 2018-032745 A). In this method, first, a wafer such as Si is prepared, and an undercoat film is formed on the wafer by CVD. Next, a resist film is formed on the undercoat film, and the resist film is exposed to light through a mask. Next, the exposed resist film is developed, and the undercoat film and wafer are etched. As a result, a plurality of protrusions are formed on the wafer. The wafer is then diced to obtain a substrate 16 having a plurality of protrusions.

[0034] 7B, a diamond film 17 is formed on the substrate 16 by CVD. Examples of CVD methods for forming the diamond film 17 include hot filament CVD. This results in a chip 14 having a plurality of protrusions 15 formed thereon.

[0035] 7(c), the tip 14 is attached to the base metal 13. The tip 14 can be attached to the base metal 13, for example, by bonding the surface of the base metal 13 opposite the attachment surface 13a to the surface of the tip 14 opposite the working surface 14a with adhesive 18. In this manner, the dresser body 11 is obtained.

[0036] In the dresser body 11 configured in this manner, the tip of each of the plurality of protrusions 15 of the tip 14 is formed at an acute angle. In addition, the tip of each of the plurality of protrusions 15 of the tip 14 is formed at an acute angle more acute than the tip of the diamond abrasive grains of the electrodeposited tip and the bonded tip.

[0037] In the dresser body 11 configured as above, the variation in height of the plurality of protrusions 15 relative to the base metal 13 is 0 mm or more and 0.2 mm or less, 0 mm or more and 0.15 mm or less, or 0 mm or more and 0.1 mm or less. This variation can be measured, for example, by a laser microscope.

[0038] The elastic member 12 is disposed on the opposite side of the base metal 13 from the tip 14. Incidentally, the polishing pad dresser 10 has a structure in which the tip 14 has a plurality of protrusions 15 that protrude from the opposite side of the base metal 13 and have a surface formed with a diamond film 17, and therefore chatter vibrations are likely to occur if the resistance between the tip 14 and the polishing pad 3 increases during dressing of the polishing pad 3. Therefore, the polishing pad dresser 10 is provided with the elastic member 12 that is disposed on the opposite side of the base metal 13 from the tip 14 in order to attenuate and suppress the chatter vibrations. In other words, the elastic member 12 is a member for suppressing the chatter vibrations.

[0039] In order to suppress chatter vibration, the Shore A hardness of the elastic member 12 is set to be equal to or greater than 45 and equal to or less than 95, equal to or greater than 45 and equal to or less than 90, or equal to or greater than 45 and equal to or less than 85. This Shore A hardness can be measured, for example, by a Shore A hardness tester.

[0040] The material of the elastic member 12 is not particularly limited, but may be, for example, rubber such as nitrile rubber, fluororubber, or silicone rubber, or resin.

[0041] 2, 4, and 6, the elastic member 12 is formed in an annular shape and is fitted into a groove 13b formed in the mounting surface 13a of the base metal 13. Therefore, the elastic member 12 extends in the circumferential direction D1 of the base metal 13 and is disposed so as to cover only a portion of the mounting surface 13a.

[0042] The thickness a of the elastic member 12 is thicker than the depth b of the groove 13b. The elastic member 12 is, for example, an O-ring having a wire diameter thicker than the depth b of the groove 13b. When the elastic member 12 is fitted into the groove 13b, the protruding length c of the elastic member 12 relative to the base metal 13 in the thickness direction D2 of the base metal 13 is, for example, 0.1 mm to 3 mm, 0.1 mm to 2 mm, or 0.1 mm to 1 mm. The protruding length c is also the value obtained by subtracting the depth b of the groove 13b from the thickness a of the elastic member 12.

[0043] The elastic member 12 may be removably attached to the base metal 13, may be non-removably attached to the base metal 13, or may be simply placed on the opposite side of the base metal 13 from the chip 14 without being attached to the base metal 13.

[0044] 1 and 2, the polishing pad dresser 10 configured as above is attached to the dressing head 7 of the dressing device 6 so that the elastic member 12 is disposed between the dressing head 7 and the base metal 13. At this time, the thickness a of the elastic member 12 is greater than the depth b of the groove 13b, so that the dressing head 7 and the base metal 13 are spaced apart. Furthermore, the elastic member 12 is not disposed over the entire surface of the mounting surface 13a, but is formed in an annular shape so as to cover only a portion of the mounting surface 13a, so that a gap d is formed between the dressing head 7 and the base metal 13. The polishing pad dresser 10 can be attached to the dressing head 7 by, for example, screwing, magnetic attraction, or the like.

[0045] As described above, in the polishing pad dresser 10 according to this embodiment, the base metal 13 is attached to the dressing head 7 of the dressing device 6, and the dressing head 7 is rotated to dress the polishing pad 3. Here, the polishing pad dresser 10 has a tip 14 that has multiple protrusions 15 that protrude from the side opposite the base metal 13 and have a surface formed with a diamond film 17. Therefore, if the resistance between the tip 14 and the polishing pad 3 increases during dressing of the polishing pad 3, chatter vibrations are likely to occur. However, since the elastic member 12 is disposed on the side of the base metal 13 opposite the tip 14, the elastic member 12 is disposed between the dressing head 7 and the base metal 13, and chatter vibrations are damped by the elastic member 12. This suppresses chatter vibrations during dressing.

[0046] Furthermore, in this polishing pad dresser 10, the Shore A hardness of the elastic member 12 is 45 or more and 95 or less, 45 or more and 90 or less, or 45 or more and 85 or less, so that the polishing pad dresser 10 can be stably attached to the dressing head 7 and chatter vibration can be suppressed.

[0047] Furthermore, in this polishing pad dresser 10, since the elastic member 12 is made of rubber, chatter vibrations can be appropriately suppressed.

[0048] Furthermore, in this polishing pad dresser 10, since the base material 16 contains silicon, the plurality of protrusions 15 of the tip 14 can be easily formed.

[0049] Furthermore, in this polishing pad dresser 10, the tip of each of the multiple protrusions 15 is formed at an acute angle, so that if the resistance between the tip 14 and the polishing pad 3 increases during dressing of the polishing pad 3, chatter vibrations are likely to occur. However, since the elastic member 12 is disposed on the side of the base metal 13 opposite the tip 14, chatter vibrations can be suppressed.

[0050] Furthermore, in this polishing pad dresser 10, the variation in height of the plurality of protrusions 15 relative to the base metal 13 is 0 mm to 0.3 mm, 0 mm to 0.2 mm, or 0 mm to 0.1 mm, so that chatter vibrations are likely to occur if the resistance between the tip 14 and the polishing pad 3 increases during dressing of the polishing pad 3. However, because the elastic member 12 is disposed on the side of the base metal 13 opposite the tip 14, chatter vibrations can be suppressed.

[0051] Furthermore, in this polishing pad dresser 10, the elastic member 12 extends in the circumferential direction D1 of the base metal 13, so that the polishing pad dresser 10 can be stably attached to the dressing head 7 and chatter vibrations can be effectively suppressed.

[0052] Furthermore, in this polishing pad dresser 10, the elastic member 12 is formed in a ring shape, so that the polishing pad dresser 10 can be stably attached to the dressing head 7 and chatter vibrations can be effectively suppressed.

[0053] Furthermore, in this polishing pad dresser 10, a groove 13b into which the elastic member 12 is fitted is formed on the mounting surface 13a of the base metal 13 opposite the chip 14. Therefore, by fitting the elastic member 12 into the groove 13b, the positioning of the elastic member 12 relative to the base metal 13 can be easily performed, and the elastic member 12 can be easily attached to the base metal 13.

[0054] Furthermore, in this polishing pad dresser 10, the thickness a of the elastic member 12 is greater than the depth b of the groove 13b, so that even when the elastic member 12 is fitted to the bottom of the groove 13b, chatter vibrations can be suppressed by the elastic member 12.

[0055] Furthermore, in this polishing pad dresser 10, when the elastic member 12 is fitted into the groove 13b, the protruding length c of the elastic member 12 relative to the base metal 13 in the thickness direction D2 of the base metal 13 is 0.1 mm or more and 3 mm or less, 0.1 mm or more and 2 mm or less, or 0.1 mm or more and 1 mm or less, so that the polishing pad dresser 10 can be stably attached to the dressing head 7 and chatter vibrations can be effectively suppressed.

[0056] In addition, in this polishing pad dresser 10, the grooves 13b are formed on the periphery of the mounting surface 13a, so that the elastic members 12 can be easily fitted into the grooves 13b. By fitting the elastic members 12 into the grooves 13b, the elastic members 12 can be arranged over a wider range, the polishing pad dresser 10 can be stably attached to the dressing head 7, and chatter vibrations can be effectively suppressed.

[0057] Furthermore, in this polishing pad dresser 10, the elastic member 12 is disposed so as to cover only a portion of the mounting surface 13a of the base metal 13 opposite the tip 14, so a gap is formed between the dresshead 7 and the base metal 13. This allows the elastic member 12 to easily expand and contract elastically, thereby effectively suppressing chatter vibrations.

[0058] The dressing device 6 according to this embodiment includes the polishing pad dresser 10 described above, and therefore can suppress chatter vibrations during dressing.

[0059] Furthermore, in this dressing device 6, a gap is formed between the dressing head 7 and the base metal 13. This allows the elastic member 12 to easily elastically expand and contract, thereby effectively suppressing chatter vibrations.

[0060] The present disclosure is not limited to the above-described embodiments, and modifications can be made as appropriate without departing from the spirit of the present disclosure.

[0061] For example, in the above embodiment, the groove 13b into which the elastic member 12 is fitted is described as being formed on the periphery of the mounting surface 13a, but the position, shape, etc. of the groove 13b into which the elastic member 12 is fitted are not particularly limited. Also, in the above embodiment, the elastic member 12 is described as being formed in an annular shape, but the shape, etc. of the elastic member are not particularly limited.

[0062] 8 is a schematic plan view showing a modified polishing pad dresser. In the polishing pad dresser 10A shown in FIG. 8, a groove 13Ab is formed concentrically with the mounting surface 13Aa of the base metal 13A at a position spaced from the peripheral edge of the mounting surface 13Aa. An annular elastic member 12A is fitted into this groove 13Ab.

[0063] 9 is a schematic plan view showing a modified polishing pad dresser. In the polishing pad dresser 10B shown in FIG. 9, a groove 13Bb is formed concentrically with the mounting surface 13Ba of the base metal 13B at a position spaced from the peripheral edge of the mounting surface 13Ba. A C-shaped or linear elastic member 12B is fitted into this groove 13Bb.

[0064] In this way, in the polishing pad dressers 10A and 10B, the grooves 13Ab and 13Bb are formed concentrically with the mounting surfaces 13Aa and 13Ba at positions spaced apart from the peripheries of the mounting surfaces 13Aa and 13Ba, thereby preventing the elastic members 12A and 12B fitted into the grooves 13Ab and 13Bb from falling out of the grooves 13Ab and 13Bb. Furthermore, fitting the elastic members 12A and 12B into the grooves 13Ab and 13Bb allows the polishing pad dressers 10A and 10B to be stably attached to the dressing head 7 and effectively suppresses chatter vibrations.

[0065] In addition, in the above embodiment, a groove 13b is formed on the mounting surface 13a and the elastic member 12 is fitted into the groove 13b, but as long as the elastic member can be attached to the mounting surface, a groove does not have to be formed on the mounting surface.

[0066] 10 is a schematic plan view showing a modified polishing pad dresser 10C, in which no grooves are formed on the mounting surface 13Ca of the base metal 13C, and multiple rectangular elastic members 12C are bonded to the mounting surface 13Ca.

[0067] By adhering the elastic member to the mounting surface in this way, the elastic member can be attached to the mounting surface without forming a groove in the mounting surface.

[0068] The elastic member may be solid and have no internal cavity, or may be hollow, such as a tube, having an internal cavity. For example, the elastic member 12 in the above embodiment, the elastic member 12A shown in Fig. 8, and the elastic member 12B shown in Fig. 9 may be solid or hollow (tube-shaped).

[0069] Next, examples and comparative examples of the present disclosure will be described. Note that the present disclosure is not limited to the following examples.

[0070] Example 1: A base film was formed on a Si wafer by CVD, a resist film was formed on the base film, and the resist film was exposed through a mask. The exposed resist film was then developed, and the base film and Si wafer were etched to form multiple protrusions on the Si wafer. The Si wafer was then diced to produce multiple substrates with multiple protrusions. A diamond film was then formed on the substrate by CVD, producing a chip with multiple protrusions on its surface formed with a diamond film. The chip size was 6 mm x 10 mm. SEM photographs of the produced chip are shown in Figures 11 and 12. The SEM photographs shown in Figures 11 and 12 were taken of the working surface of a chip on which multiple protrusions were formed. As shown in Figures 11 and 12, each of the multiple protrusions was formed in a hexagonal pyramid shape with an acute-angled tip. Furthermore, the multiple protrusions had approximately the same height.

[0071] Next, five chips were attached to the base metal to form a dresser body. A groove was formed on the periphery of the mounting surface of the base metal opposite the chips, and an O-ring, an elastic member, was fitted into the groove to position the O-ring on the opposite side of the base metal from the chips. This resulted in the polishing pad dresser of Example 1. The outer diameter of the base metal was 101.6 mm, the thickness of the base metal was 4.3 mm, the depth of the groove was 1.5 mm, and the thickness of the O-ring was 2.0 mm.

[0072] A chatter vibration evaluation was performed using the polishing pad dresser of Example 1. In the chatter vibration evaluation, the base metal was attached to the dressing head of the polishing apparatus so that an O-ring was placed between the dressing head and the base metal, and the dressing head was rotated while the turntable and polishing pad were rotated. Slurry was supplied from a nozzle onto the polishing pad, and the dressing head pressed the chip against the polishing pad with a predetermined pressure, thereby dressing the polishing pad. The degree of chatter vibration during dressing was also evaluated. In the evaluation, the chatter value indicating the degree of chatter vibration was measured by integrating the vibration acceleration obtained from an acceleration sensor attached to the dressing head from 0 kHz to 1 kHz. The results are shown in FIG. 13.

[0073] (Example 2) A polishing pad dresser of Example 2 was fabricated under the same conditions as Example 1, except that seven chips were attached to the base metal, and the polishing pad dresser of Example 2 was used to perform the same chatter vibration evaluation as in Example 1. The results are shown in Figure 13.

[0074] (Example 3) A polishing pad dresser of Example 3 was fabricated under the same conditions as Example 1, except that nine chips were attached to the base metal, and the polishing pad dresser of Example 3 was used to perform the same chatter vibration evaluation as in Example 1. The results are shown in Figure 13.

[0075] Comparative Example 1 A polishing pad dresser of Comparative Example 1 was fabricated under the same conditions as in Example 1, except that no groove was formed on the mounting surface of the base metal and no O-ring was used. The polishing pad dresser of Comparative Example 1 was used to perform the same chatter vibration evaluation as in Example 1. Note that, because the polishing pad dresser of Comparative Example 1 did not use an O-ring, the base metal was directly attached to the dressing head. The results are shown in Figure 13.

[0076] (Comparative Example 2) A polishing pad dresser of Comparative Example 2 was fabricated under the same conditions as Example 2, except that no groove was formed on the mounting surface of the base metal and no O-ring was used. The polishing pad dresser of Comparative Example 2 fabricated was used to perform the same chatter vibration evaluation as Example 1. Note that, because the polishing pad dresser of Comparative Example 2 did not use an O-ring, the base metal was directly attached to the dressing head. The results are shown in Figure 13.

[0077] (Comparative Example 3) A polishing pad dresser of Comparative Example 3 was fabricated under the same conditions as in Example 3, except that no groove was formed on the mounting surface of the base metal and no O-ring was used. The polishing pad dresser of Comparative Example 3 thus fabricated was used to perform the same chatter vibration evaluation as in Example 1. Note that, because the polishing pad dresser of Comparative Example 3 did not use an O-ring, the base metal was directly attached to the dressing head. The results are shown in Figure 13.

[0078] (Evaluation Results) Figure 13 is a graph showing the results of Examples 1 to 3 and Comparative Examples 1 to 3. As shown in Figure 13, Examples 1 to 3, in which the O-ring was placed on the opposite side of the base metal from the tip, had significantly smaller chatter values ​​than Comparative Examples 1 to 3, in which no O-ring was used. Furthermore, Examples 1 to 3 hardly generated any chatter vibration. From these results, it was found that chatter vibration can be suppressed by placing the O-ring on the opposite side of the base metal from the tip.

[0079] 1...polishing apparatus, 2...rotary table, 3...polishing pad, 4...polishing head, 5...nozzle, 6...dressing device, 7...dressing head, 10, 10A, 10B, 10C...polishing pad dresser, 11...dresser body, 12, 12A, 12B, 12C...elastic member, 13, 13A, 13B, 13C...base metal, 13a, 13Aa, 13Ba, 13Ca...mounting surface, 13b, 13Ab, 13Bb...groove, 14...tip, 14a...working surface, 15...protrusion, 16...substrate, 17...diamond film, 18...adhesive, a...thickness, b...depth, c...protrusion length, D1...circumferential direction, D2...thickness direction.

Claims

1. A dresser for a polishing pad comprising: a dresser body having a circular base metal and a tip arranged on the base metal; and an elastic member arranged on the side of the base metal opposite the tip, the tip having a plurality of protrusions protruding on the side opposite the base metal and having a surface formed with a diamond film.

2. The polishing pad dresser according to claim 1, wherein the Shore A hardness of said elastic member is 45 or more and 95 or less.

3. The polishing pad dresser according to claim 1, wherein the elastic member is rubber.

4. The dresser for a polishing pad according to claim 1, wherein the tip has a substrate and the diamond film formed on the substrate, the substrate containing silicon.

5. The dresser for a polishing pad according to claim 1, wherein a tip of each of said plurality of protrusions is formed at an acute angle.

6. The dresser for a polishing pad according to claim 1, wherein the variation in height of said plurality of protrusions relative to said base metal is not less than 0 mm and not more than 0.3 mm.

7. The polishing pad dresser according to claim 1, wherein the elastic member extends in a circumferential direction of the base metal.

8. The polishing pad dresser according to claim 1, wherein the elastic member is formed in an annular shape.

9. The dresser for a polishing pad according to claim 1, wherein a groove into which said elastic member is fitted is formed on a mounting surface of said base metal opposite to said tip.

10. The polishing pad dresser according to claim 9, wherein the elastic member has a thickness greater than a depth of the groove.

11. The dresser for a polishing pad according to claim 9, wherein a protruding length of said elastic member relative to said base metal in a thickness direction of said base metal when said elastic member is fitted into said groove is 0.1 mm or more and 3 mm or less.

12. The polishing pad dresser according to claim 9, wherein the groove is formed in the peripheral portion of the mounting surface.

13. The dresser for a polishing pad according to claim 9, wherein the groove is formed concentrically with the mounting surface at a position spaced from a peripheral edge of the mounting surface.

14. The dresser for a polishing pad according to claim 1, wherein said elastic member is disposed so as to cover only a portion of the mounting surface of said base metal opposite to said tip.

15. A dressing device comprising: a polishing pad dresser according to any one of claims 1 to 14, which is positioned above a polishing pad; and a rotatable dressing head to which said polishing pad dresser is attached, said polishing pad dresser being attached to said dressing head such that said elastic member is disposed between said dressing head and said base metal.

16. The dressing device according to claim 15, wherein a gap is formed between the dressing head and the base metal.

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