Polishing liquid supply apparatus, polishing apparatus, and polishing liquid supply method

Abstract

The concentration of the additive is adjusted while keeping the concentration of the slurry constant.SOLUTION: The polishing liquid supply device 370 includes a first flow rate controller 386 capable of adjusting a flow rate of a first polishing liquid having a predetermined slurry concentration and containing an additive, a second flow rate controller 396 capable of adjusting a flow rate of a second polishing liquid having the same slurry concentration as the first polishing liquid, a polishing liquid mixer 398 that mixes the first polishing liquid discharged from the first flow rate controller 386 and the second polishing liquid discharged from the second flow rate controller 396, and a nozzle 399 that supplies a third polishing liquid discharged from the polishing liquid mixer 398 to the polishing table 350.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present application relates to a polishing liquid supply device, a polishing apparatus, and a polishing liquid supply method. [Background technology]

[0002] CMP (Chemical Mechanical Polishing) equipment is one type of substrate polishing equipment used in semiconductor processing. Polishing equipment such as CMP equipment can be broadly categorized into "face-up type" (where the surface to be polished of the substrate faces upward) and "face-down type" (where the surface to be polished of the substrate faces downward) depending on the direction in which the surface to be polished of the substrate faces.

[0003] A face-down polishing apparatus includes a top ring that holds a substrate with its surface to be polished facing downward, a polishing table to which a polishing pad is attached, and a supply device that supplies a polishing liquid onto the polishing table (polishing pad). The polishing apparatus is configured to polish the surface of the substrate by rotating the top ring and polishing table while supplying the polishing liquid onto the polishing table and pressing the substrate against the polishing pad.

[0004] In semiconductor processes that use such polishing equipment, for example, Mo / Ru thin films have begun to be used. Mo / Ru has higher hardness and strength than other metals and is highly corrosive chemically, which means that existing polishing solutions have the disadvantage of requiring long polishing times. For this reason, it is known that additives such as hydrogen peroxide are supplied to CMP processes. Patent Document 1 discloses a polishing equipment that supplies a solution containing an abrasive (slurry) and a solution containing an additive mixed at a desired ratio. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-071720 Summary of the Invention [Problem to be solved by the invention]

[0006] According to the conventional technology described in Patent Document 1, the concentration of the additive can be adjusted relative to the total flow rate, but this has the disadvantage of simultaneously changing the concentration of the slurry. For example, as the concentration of the additive increases, the concentration of the slurry becomes thinner. This can lead to a problem of reduced polishing efficiency in the CMP process.

[0007] Therefore, one object of the present invention is to adjust the concentration of additives while maintaining the concentration of the slurry constant. [Means for solving the problem]

[0008] According to one embodiment, a polishing liquid supply device is disclosed, which includes a first flow rate controller capable of adjusting the flow rate of a first polishing liquid having a predetermined slurry concentration and containing an additive; a second flow rate controller capable of adjusting the flow rate of a second polishing liquid having the same slurry concentration as the first polishing liquid; a polishing liquid mixer that mixes the first polishing liquid discharged from the first flow rate controller and the second polishing liquid discharged from the second flow rate controller; and a nozzle that supplies the third polishing liquid discharged from the polishing liquid mixer to a polishing table. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a plan view showing an overall configuration of a substrate processing apparatus according to one embodiment; [Figure 2] FIG. 2 is a perspective view schematically illustrating a configuration of a polishing unit according to one embodiment. [Figure 3] FIG. 1 is a diagram illustrating a configuration of a polishing liquid supply device according to an embodiment. [Figure 4] FIG. 10 is a diagram showing the change in slurry concentration when the additive concentration is changed for the present embodiment and the comparative example. [Figure 5] FIG. 1 is a diagram illustrating a configuration of a polishing liquid supply device according to an embodiment. [Figure 6] 1 is a flowchart of a polishing liquid supply method according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of a polishing apparatus and a polishing liquid supply method according to the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, identical or similar elements are designated by identical or similar reference symbols, and duplicate descriptions of identical or similar elements may be omitted in the description of each embodiment. Furthermore, features shown in each embodiment may also be applied to other embodiments as long as they are not mutually inconsistent.

[0011] FIG. 1 is a plan view showing the overall configuration of a substrate processing apparatus 1000 according to one embodiment. The substrate processing apparatus 1000 shown in FIG. 1 includes a load unit 100, a transfer unit 200, a polishing unit 300, a drying unit 500, and an unload unit 600. In the illustrated embodiment, the transfer unit 200 includes two transfer units 200A and 200B, and the polishing unit 300 includes two polishing units 300A and 300B. In one embodiment, each of these units can be formed independently. By forming these units independently, substrate processing apparatuses 1000 with different configurations can be easily formed by arbitrarily combining the number of each unit. The substrate processing apparatus 1000 also includes a control device 900, which controls each component of the substrate processing apparatus 1000. In one embodiment, the control device 900 can be configured as a general computer including an input / output device, a calculation device, a storage device, and the like.

[0012] <Load unit> The load unit 100 is a unit for introducing a substrate WF before processing such as polishing and cleaning into the substrate processing apparatus 1000. In one embodiment, the load unit 100 is configured to comply with the SMEMA (Surface Mount Equipment Manufacturers Association) Mechanical Device Interface Standard (IPC-SMEMA-9851).

[0013] In the illustrated embodiment, the transport mechanism of the load unit 100 includes multiple transport rollers 202 and multiple roller shafts 204 to which the transport rollers 202 are attached. In the embodiment shown in FIG. 1, three transport rollers 202 are attached to each roller shaft 204. The substrate WF is placed on the transport rollers 202, and the substrate WF is transported by the rotation of the transport rollers 202. The transport rollers 202 may be attached at any position on the roller shaft 204 as long as they can stably transport the substrate WF. However, since the transport rollers 202 come into contact with the substrate WF, they should be positioned so that they contact an area of ​​the substrate WF that is to be processed without causing any problems. In one embodiment, the transport rollers 202 of the load unit 100 may be made of a conductive polymer. In one embodiment, the transport rollers 202 are electrically grounded via the roller shafts 204 or the like. This is to prevent the substrate WF from being charged and damaging the substrate WF. In one embodiment, the load unit 100 may also be provided with an ionizer (not shown) to prevent the substrate WF from being charged.

[0014] <Transport unit> 1 includes two transport units 200A and 200B. The two transport units 200A and 200B can have the same configuration, and therefore will be collectively referred to as the transport unit 200 in the following description.

[0015] The transport unit 200 shown in the figure is equipped with a plurality of transport rollers 202 for transporting the substrate WF. By rotating the transport rollers 202, the substrate WF on the transport rollers 202 can be transported in a predetermined direction. The transport rollers 202 of the transport unit 200 may be formed from a conductive polymer or a non-conductive polymer. The transport rollers 202 are driven by a motor (not shown). The substrate WF is transported to a substrate transfer position by the transport rollers 202.

[0016] In one embodiment, the transport unit 200 includes a cleaning nozzle 284. The cleaning nozzle 284 is connected to a cleaning liquid supply source (not shown). The cleaning nozzle 284 is configured to supply the cleaning liquid to the substrate WF transported by the transport rollers 202.

[0017] <Drying unit> The drying unit 500 is an apparatus for drying the substrate WF. In the substrate processing apparatus 1000 shown in FIG. 1, the drying unit 500 dries the substrate WF that has been polished in the polishing unit (polishing apparatus) 300 and then cleaned in the cleaning section of the transfer unit 200. As shown in FIG. 1, the drying unit 500 is disposed downstream of the transfer unit 200. The drying unit 500 has a nozzle 530 for spraying gas toward the substrate WF being transported on the transport rollers 202. The gas can be, for example, compressed air or nitrogen. The substrate WF can be dried by having the drying unit 500 blow away water droplets on the substrate WF being transported.

[0018] <Unload unit> The unload unit 600 is a unit for unloading the substrate WF after processing such as polishing and cleaning to the outside of the substrate processing apparatus 1000. In the substrate processing apparatus 1000 shown in FIG. 1, the unload unit 600 receives the substrate after drying in the drying unit 500. As shown in FIG. 1, the unload unit 600 is disposed downstream of the drying unit 500. In one embodiment, the unload unit 600 is configured to comply with the Mechanical Device Interface Standard (IPC-SMEMA-9851) of the SMEMA (Surface Mount Equipment Manufacturers Association).

[0019] <Polishing unit> Fig. 2 is a perspective view schematically illustrating the configuration of a polishing unit 300 according to one embodiment. The substrate processing apparatus 1000 shown in Fig. 1 includes two polishing units 300A and 300B. The two polishing units 300A and 300B can have the same configuration, and therefore will be collectively referred to as the polishing unit 300 below.

[0020] As shown in FIG. 2 , the polishing unit 300 includes a polishing table 350 and a top ring 302 constituting a polishing head that holds a substrate to be polished and presses it against the polishing surface of the polishing table 350. The polishing table 350 is connected to a polishing table rotation motor (not shown) disposed below the table shaft 351 and is rotatable about the table shaft 351. A polishing pad 352 is attached to the upper surface of the polishing table 350, and a surface 352a of the polishing pad 352 constitutes the polishing surface that polishes the substrate. In one embodiment, the polishing pad 352 may be attached via a layer that facilitates removal from the polishing table 350. Such a layer may be, for example, a silicone layer or a fluorine-based resin layer, and may be, for example, one described in Japanese Patent Application Laid-Open No. 2014-176950. Note that, although the present embodiment illustrates an example in which the polishing unit 300 polishes a rectangular substrate (a square substrate), the shape of the substrate to be polished may be any shape. The polishing unit 300 may be configured to polish, for example, a disk-shaped substrate (round substrate). In this embodiment, the substrate includes a loading unit 100, a transporting unit 200, a polishing unit 300, a drying unit 500, an unloading unit 600, and the like. Although the substrate processing apparatus 1000 has been described, the present invention is not limited to this, and the substrate processing apparatus (polishing apparatus) may include only the polishing unit 300.

[0021] 2, in one embodiment, the polishing unit 300 includes an atomizer 358 (see FIG. 1) for spraying a liquid or a mixture of liquid and gas toward the polishing pad 352. The liquid sprayed from the atomizer 358 is, for example, pure water, and the gas is, for example, nitrogen gas.

[0022] The top ring 302 is connected to a top ring shaft 18, which is movable up and down relative to a swing arm 360 by a vertical movement mechanism 319. The vertical movement of the top ring shaft 18 moves the entire top ring 302 up and down relative to the swing arm 360, thereby positioning it. The top ring shaft 18 is rotated by a top ring rotation motor (not shown). The rotation of the top ring shaft 18 causes the top ring 302 to rotate around the top ring shaft 18.

[0023] The top ring 302 is adapted to hold a substrate on its underside. The swing arm 360 is rotatable about a support shaft 362. By rotating the swing arm 360, the top ring 302 can move between the substrate transfer position of the transport unit 200 and above the polishing table 350. By lowering the top ring shaft 18, the top ring 302 can be lowered to press the substrate against the surface (polishing surface) 352a of the polishing pad 352. At this time, the top ring 302 and the polishing table 350 are rotated, and a polishing liquid is supplied onto the polishing pad 352 from a polishing liquid supply device 370 (described later). This allows the substrate WF to be pressed against the polishing surface 352a of the polishing pad 352, thereby polishing the surface of the substrate. During polishing of the substrate WF, the arm 360 may be fixed or swingable so that the top ring 302 passes through the center of the polishing pad 352 (so as to cover the through-hole 357 of the polishing pad 352).

[0024] The up-and-down movement mechanism 319 that moves the top ring shaft 18 and the top ring 302 up and down includes a bridge 28 that rotatably supports the top ring shaft 18 via a bearing 321, a ball screw 32 attached to the bridge 28, a support base 29 supported by a support column 130, and an AC servo motor 38 provided on the support base 29. The support base 29 that supports the servo motor 38 is fixed to a swing arm 360 via the support column 130.

[0025] The ball screw 32 includes a screw shaft 32a connected to a servo motor 38 and a nut 32b onto which the screw shaft 32a is threaded. The top ring shaft 18 moves up and down integrally with the bridge 28. Therefore, when the servo motor 38 is driven, the bridge 28 moves up and down via the ball screw 32, which in turn moves the top ring shaft 18 and the top ring 302 up and down.

[0026] The polishing unit 300 according to one embodiment includes a dressing unit 356 that dresses the polishing surface 352a of the polishing pad 352. The dressing unit 356 includes a dresser 50 that slides against the polishing surface 352a, a dresser shaft 51 to which the dresser 50 is connected, an air cylinder 53 attached to the upper end of the dresser shaft 51, and a swing arm 55 that rotatably supports the dresser shaft 51. The lower portion of the dresser 50 is formed by a dressing member 50a, and needle-shaped diamond particles are attached to the underside of the dressing member 50a. The air cylinder 53 is disposed on a support base 57 supported by struts 56, and the struts 56 are fixed to the swing arm 55.

[0027] The swing arm 55 is driven by a motor (not shown) to rotate around a support shaft 58. The dresser shaft 51 is rotated by a motor (not shown), and the rotation of the dresser shaft 51 causes the dresser 50 to rotate around the dresser shaft 51. The air cylinder 53 moves the dresser 50 up and down via the dresser shaft 51, and presses the dresser 50 against the polishing surface 352a of the polishing pad 352 with a predetermined pressing force.

[0028] The polishing surface 352a of the polishing pad 352 is dressed as follows. The dresser 50 is pressed against the polishing surface 352a by the air cylinder 53, and at the same time, pure water is supplied to the polishing surface 352a from a pure water supply nozzle (not shown). In this state, the dresser 50 rotates around the dresser shaft 51, causing the lower surface (diamond particles) of the dressing member 50a to slide against the polishing surface 352a. In this way, the dresser 50 scrapes off the polishing pad 352, and the polishing surface 352a is dressed.

[0029] The polishing unit (polishing apparatus) 300 includes a polishing liquid supply device 370 for supplying a polishing liquid. Details of the polishing liquid supply device 370 will be described below. Figure 3 is a diagram schematically showing the configuration of the polishing liquid supply device according to one embodiment.

[0030] 3, the polishing liquid supply device 370 includes a first flow rate controller 386. The first flow rate controller 386 is configured to adjust the flow rate of a first polishing liquid having a predetermined slurry concentration and containing an additive (e.g., hydrogen peroxide, but not limited to this). More specifically, the polishing liquid supply device 370 includes a first chemical liquid supply device 382 that mixes the slurry, the additive, and pure water to generate the first polishing liquid. The first flow rate controller 386 is configured to adjust the flow rate of the first polishing liquid generated by the first chemical liquid supply device 382.

[0031] The polishing liquid supply device 370 also includes a first valve 384. The first valve 384 is configured to switch the flow path so that the first polishing liquid is sent to the first flow rate controller 386 when the polishing liquid is supplied to the polishing table 350, and the first polishing liquid is returned to the first chemical liquid supply device 382 when the polishing liquid is not supplied to the polishing table 350. The polishing liquid supply device 370 also includes an additive concentration sensor 383. The additive concentration sensor 383 is configured to feed back the actual additive concentration of the first polishing liquid to the first flow rate controller 386 in order to correct a discrepancy between a predetermined additive concentration specified by a user for the first polishing liquid generated by the first chemical liquid supply device 382 and the actual additive concentration of the first polishing liquid flowing to the first flow rate controller 386. The polishing liquid supply device 370 also includes a constant pressure valve 385 for adjusting the pressure of the first polishing liquid flowing to the first flow rate controller 386 to a predetermined pressure.

[0032] The polishing liquid supply device 370 also includes a second flow rate controller 396. The second flow rate controller 396 is configured to adjust the flow rate of a second polishing liquid having the same slurry concentration as the first polishing liquid. More specifically, the polishing liquid supply device 370 includes a second chemical liquid supply device 392 that mixes a slurry with pure water to produce the second polishing liquid. The second flow rate controller 396 is configured to adjust the flow rate of the second polishing liquid produced by the second chemical liquid supply device 392. Note that, in this specification, the term "a second polishing liquid having the same slurry concentration as the first polishing liquid" refers to a second polishing liquid having a slurry concentration within a predetermined range (e.g., within ±1%, preferably within ±0.5%, and more preferably within ±0.1%) of the slurry concentration of the first polishing liquid. Furthermore, the first chemical liquid supply device 382 and the second chemical liquid supply device 392 may be any device, regardless of its size, as long as it has the function of mixing within a container such as a storage tank, or within a pipe such as a junction pipe.

[0033] The polishing liquid supply device 370 also includes a second valve 394. The second valve 394 The flow path is configured to send the second polishing liquid to the second flow controller 396 when polishing liquid is supplied to the polishing table 350, and to switch the flow path so that the second polishing liquid is returned to the second chemical liquid supply device 392 when polishing liquid is not supplied to the polishing table 350.

[0034] The polishing liquid supply device 370 includes a polishing liquid mixer 398 that mixes a first polishing liquid discharged from a first flow rate controller 386 and a second polishing liquid discharged from a second flow rate controller 396. The polishing liquid supply device 370 includes a nozzle 399 that supplies the third polishing liquid discharged from the polishing liquid mixer 398 to the polishing table 350 (polishing pad 352). The nozzle 399 is installed above the polishing table 350, and the polishing liquid is supplied by the nozzle 399 onto the polishing pad 352 attached to the polishing table 350.

[0035] As an example, the polishing liquid supply device 370 of this embodiment is configured so that the user can specify the total flow rate and additive concentration of the polishing liquid (third polishing liquid) to be supplied to the polishing table 350. Here, the total flow rate refers to the total flow rate of the first polishing liquid discharged from the first flow rate controller 386 and the flow rate of the second polishing liquid discharged from the second flow rate controller 396.

[0036] The first flow rate controller 386 is configured to adjust the flow rate of the first polishing liquid based on the total flow rate and additive concentration specified by the user and the additive concentration of the first polishing liquid generated by the first chemical liquid supply device 382. For example, suppose that the first chemical liquid supply device 382 mixes the additive, slurry, and DIW so that the additive concentration is 5%, the slurry concentration is 10%, and the DIW (pure water) is 85%. On the other hand, suppose that the second chemical liquid supply device 392 mixes the slurry and DIW so that the slurry concentration is 10%, the same as the first polishing liquid, and the DIW (pure water) is 90%. Here, suppose that the total flow rate of the third polishing liquid specified by the user is 500 ml / min and the additive concentration is 2%.

[0037] In this case, the first flow rate controller 386 adjusts the flow rate of the first polishing liquid to 200 ml / min (= 500 ml / min × additive concentration of the third polishing liquid 2% / additive concentration of the first polishing liquid 5%) so as to satisfy the overall flow rate and additive concentration specified by the user.

[0038] On the other hand, the second flow rate controller 396 is configured to adjust the flow rate of the second polishing liquid based on the total flow rate specified by the user and the flow rate of the first polishing liquid. More specifically, the second flow rate controller 396 is configured to adjust the flow rate of the second polishing liquid based on the result of subtracting the flow rate of the first polishing liquid from the total flow rate specified by the user. In the above example, the second flow rate controller 396 adjusts the flow rate of the second polishing liquid to 300 ml / min (= flow rate of the third polishing liquid 500 ml / min - flow rate of the first polishing liquid 200 ml / min).

[0039] According to this embodiment, it is possible to adjust the concentration of the additive while maintaining a constant concentration of the slurry. This point will be explained below. Fig. 4 is a diagram showing the change in the slurry concentration when the additive concentration is changed for this embodiment and a comparative example. In Fig. 4, the horizontal axis represents the concentration of the additive (hydrogen peroxide, as an example) of the third polishing liquid specified by the user, and the vertical axis represents the slurry concentration of the third polishing liquid.

[0040] In the comparative example, a first chemical liquid supply device mixes additive and DIW to achieve a predetermined additive concentration, and a second chemical liquid supply device mixes slurry and DIW to achieve a predetermined slurry concentration. In the comparative example, a first flow rate controller is configured to adjust the flow rate of the first polishing liquid based on the total flow rate and additive concentration specified by the user and the additive concentration of the first polishing liquid generated by the first chemical liquid supply device. Furthermore, in the comparative example, a second flow rate controller is configured to adjust the flow rate of the first polishing liquid based on the total flow rate and additive concentration specified by the user. The flow rate of the second polishing liquid is adjusted based on the result of subtracting the flow rate.

[0041] In this case, as shown in Fig. 4, in the comparative example, the slurry concentration of the third polishing liquid changes as the additive concentration of the third polishing liquid specified by the user changes. For example, as the additive concentration specified by the user increases, the slurry concentration of the third polishing liquid decreases. If the slurry concentration of the third polishing liquid decreases in this way, the polishing efficiency in the CMP process may decrease.

[0042] In contrast, as shown in FIG. 4, in this embodiment, the first flow rate controller 386 and the second flow rate controller 396 are configured to adjust the flow rates of the first polishing liquid and the second polishing liquid having the same slurry concentration, so that the concentration of the additive can be adjusted while maintaining the slurry concentration constant.

[0043] For example, using the above example, suppose the total flow rate of the third polishing liquid specified by the user is 500 ml / min and the additive concentration has changed from 2% to 3%. In this case, the first flow rate controller 386 adjusts the flow rate of the first polishing liquid to 300 ml / min (= 500 ml / min × additive concentration of the third polishing liquid 3% / additive concentration of the first polishing liquid 5%) so as to satisfy the total flow rate and additive concentration specified by the user.

[0044] On the other hand, the second flow rate controller 396 adjusts the flow rate of the second polishing liquid to 200 ml / min (=flow rate of the third polishing liquid 500 ml / min - flow rate of the first polishing liquid 300 ml / min) based on the result of subtracting the flow rate of the first polishing liquid from the total flow rate specified by the user. In this case, the third polishing liquid supplied to the polishing table 350 has a total flow rate of 500 ml / min and an additive concentration that changes from 2% to 3%, as specified by the user, but the slurry concentration is maintained at 10%.

[0045] As described above, according to this embodiment, since the first flow rate controller 386 and the second flow rate controller 396 discharge slurries of the same concentration, the slurry concentration of the combined total flow rate of the third polishing liquid is always constant. In other words, according to this embodiment, by matching the slurries of the first polishing liquid and the second polishing liquid, it is possible to control the concentration of the additive while maintaining a constant slurry concentration of the third polishing liquid supplied to the polishing table 350. Note that when no additive is used, it is possible to polish a substrate by using only the second flow rate controller 396.

[0046] In the above embodiment, the first chemical liquid supply device 382 generates the first polishing liquid by mixing the additive, the slurry, and DIW upstream of the first valve 384, but this is not limiting. Fig. 5 is a diagram schematically illustrating the configuration of a polishing liquid supply device according to one embodiment. Only the configuration different from the above embodiment shown in Fig. 3 will be described below.

[0047] 5, the first chemical liquid supply device 382 may include a first mixer 382-1 that mixes the slurry and DIW upstream of the first valve 384, and a second mixer 382-2 that mixes an additive into the chemical liquid generated by the first mixer 382-1 downstream of the first valve 384. As in the above embodiment, the first chemical liquid supply device 382 is configured to mix the slurry, the additive, and deionized water to thereby generate a first polishing liquid having a predetermined slurry concentration and containing the additive.

[0048] According to this embodiment, the concentration of the additive can be adjusted while maintaining the concentration of the slurry constant, as in the above embodiment. In addition, according to this embodiment, when the additive, the slurry, and the DIW are premixed and left to stand, or when the additive, the slurry, and the DIW are premixed and transported in a pipeline for a certain distance, the slurry aggregates due to a chemical reaction, and the dispersion becomes difficult. Furthermore, even if it is difficult to premix the additive, the slurry, and the DIW at the installation location of the polishing liquid supply device 370, it is possible to generate a first polishing liquid that has a predetermined slurry concentration and also contains the additive.

[0049] Next, a polishing liquid supply method according to this embodiment will be described. Fig. 6 is a flowchart of the polishing liquid supply method according to one embodiment.

[0050] The polishing liquid supply method of this embodiment uses a first flow rate controller 386 to adjust the flow rate of the first polishing liquid generated by the first chemical liquid supply device 382 (first adjustment step 102). As described above, the first polishing liquid is a polishing liquid that has a predetermined slurry concentration and contains an additive. In the first adjustment step 102, the flow rate of the first polishing liquid is adjusted based on the overall flow rate and additive concentration specified by the user and the additive concentration of the first polishing liquid.

[0051] Next, the polishing liquid supply method uses the second flow rate controller 396 to adjust the flow rate of the second polishing liquid generated by the second chemical liquid supply device 392 (second adjusting step 104). As described above, the second polishing liquid is a polishing liquid having the same slurry concentration as the first polishing liquid. In the second adjusting step 104, the flow rate of the second polishing liquid is adjusted based on the total flow rate specified by the user and the flow rate of the first polishing liquid adjusted in the first adjusting step 102.

[0052] Next, in the polishing liquid supplying method, the first polishing liquid whose flow rate has been adjusted in the first adjusting step 102 and the second polishing liquid whose flow rate has been adjusted in the second adjusting step 104 are mixed using the polishing liquid mixer 398 (mixing step 106). Next, in the polishing liquid supplying method, the third polishing liquid mixed in the mixing step 106 is supplied to the polishing table 350 using the nozzle 399 (supply step 108).

[0053] According to the polishing liquid supply method of this embodiment, the concentration of the additive can be adjusted while keeping the concentration of the slurry constant.

[0054] Although several embodiments of the present invention have been described above, the above-described embodiments of the present invention are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The present invention may be modified or improved without departing from the spirit thereof, and the present invention naturally includes equivalents thereof. Furthermore, any combination or omission of the components described in the claims and specification is possible within the scope of solving at least part of the above-described problems or achieving at least part of the effects.

[0055] As one embodiment, the present application discloses a polishing liquid supply device including: a first flow rate controller capable of adjusting the flow rate of a first polishing liquid having a predetermined slurry concentration and containing an additive; a second flow rate controller capable of adjusting the flow rate of a second polishing liquid having the same slurry concentration as the first polishing liquid; a polishing liquid mixer that mixes the first polishing liquid discharged from the first flow rate controller and the second polishing liquid discharged from the second flow rate controller; and a nozzle that supplies the third polishing liquid discharged from the polishing liquid mixer to a polishing table.

[0056] Furthermore, as one embodiment, the present application discloses a polishing liquid supply device further including a first chemical liquid supply device that mixes a slurry, an additive, and pure water to generate the first polishing liquid, and a second chemical liquid supply device that mixes the slurry and pure water to generate the second polishing liquid, wherein the first flow rate controller is configured to adjust the flow rate of the first polishing liquid generated by the first chemical liquid supply device, and the second flow rate controller is configured to adjust the flow rate of the second polishing liquid generated by the second chemical liquid supply device.

[0057] Furthermore, as one embodiment, the present application discloses a polishing liquid supply device configured such that the first flow rate controller adjusts the flow rate of the first polishing liquid based on a specified overall flow rate and additive concentration and the additive concentration of the first polishing liquid produced by the first chemical liquid supply device, and the second flow rate controller adjusts the flow rate of the second polishing liquid based on the specified overall flow rate and the flow rate of the first polishing liquid.

[0058] Furthermore, the present application discloses, as one embodiment, a polishing liquid supply device, in which the additive includes hydrogen peroxide.

[0059] Furthermore, as one embodiment, the present application discloses a polishing apparatus including a top ring that holds a substrate with the surface to be polished facing downward, a polishing table to which a polishing pad is attached, and any one of the polishing liquid supply devices described above for supplying the third polishing liquid onto the polishing table.

[0060] Furthermore, as one embodiment, the present application discloses a polishing liquid supply method including a first adjusting step of adjusting the flow rate of a first polishing liquid having a predetermined slurry concentration and containing an additive; a second adjusting step of adjusting the flow rate of a second polishing liquid having the same slurry concentration as the first polishing liquid; a mixing step of mixing the first polishing liquid whose flow rate has been adjusted by the first adjusting step with the second polishing liquid whose flow rate has been adjusted by the second adjusting step; and a supplying step of supplying the third polishing liquid mixed by the mixing step to a polishing table.

[0061] Furthermore, as one embodiment, the present application discloses a polishing liquid supply method, wherein the first adjustment step is configured to adjust the flow rate of the first polishing liquid based on a specified overall flow rate and additive concentration and the additive concentration of the first polishing liquid, and the second adjustment step is configured to adjust the flow rate of the second polishing liquid based on the specified overall flow rate and the flow rate of the first polishing liquid adjusted by the first adjustment step. [Explanation of symbols]

[0062] 300 Polishing unit (polishing device) 302 Top Ring 350 Polishing Table 352 Polishing Pad 370 Polishing liquid supply device 382 First chemical supply device 383 Additive concentration sensor 386 First Flow Controller 392 Second chemical supply device 396 Second Flow Controller 398 Polishing liquid mixer 399 nozzle WF board

Claims

1. a first flow rate controller capable of adjusting a flow rate of a first polishing liquid having a predetermined slurry concentration and containing an additive; a second flow rate controller capable of adjusting the flow rate of a second polishing liquid having the same slurry concentration as the first polishing liquid; a polishing liquid mixer that mixes the first polishing liquid discharged from the first flow rate controller and the second polishing liquid discharged from the second flow rate controller; a nozzle for supplying the third polishing liquid discharged from the polishing liquid mixer to a polishing table; A polishing liquid supply device comprising:

2. a first chemical liquid supply device that mixes a slurry, an additive, and pure water to generate the first polishing liquid; a second chemical liquid supply device that mixes the slurry with pure water to generate the second polishing liquid; further comprising the first flow rate controller adjusts the flow rate of the first polishing liquid generated by the first chemical liquid supply device; the second flow rate controller is configured to adjust the flow rate of the second polishing liquid generated by the second chemical liquid supply device; 2. The polishing liquid supply device according to claim 1.

3. the first flow rate controller adjusts the flow rate of the first polishing liquid based on a designated overall flow rate and additive concentration and the additive concentration of the first polishing liquid produced by the first chemical liquid supply device; the second flow rate controller is configured to adjust the flow rate of the second polishing liquid based on the specified total flow rate and the flow rate of the first polishing liquid.

3. The polishing liquid supply device according to claim 2.

4. The additive includes hydrogen peroxide.

4. The polishing liquid supply device according to claim 3.

5. a top ring that holds the substrate so that the surface to be polished faces downward; a polishing table to which a polishing pad is attached; a polishing liquid supplying device according to claim 1 for supplying the third polishing liquid onto the polishing table; Including, Polishing equipment.

6. a first adjusting step of adjusting a flow rate of a first polishing liquid having a predetermined slurry concentration and containing an additive; a second adjusting step of adjusting a flow rate of a second polishing liquid having the same slurry concentration as that of the first polishing liquid; a mixing step of mixing the first polishing liquid, the flow rate of which has been adjusted in the first adjusting step, and the second polishing liquid, the flow rate of which has been adjusted in the second adjusting step; a supplying step of supplying the third polishing liquid mixed in the mixing step to a polishing table; A polishing liquid supply method comprising:

7. the first adjusting step adjusts the flow rate of the first polishing liquid based on a designated total flow rate and additive concentration and the additive concentration of the first polishing liquid; the second adjusting step is configured to adjust the flow rate of the second polishing liquid based on the specified total flow rate and the flow rate of the first polishing liquid adjusted in the first adjusting step.

7. The polishing liquid supply method according to claim 6.

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