Liquid supply device and polishing device

Abstract

To provide a liquid supply device and a polishing device, which can secure a space for installing apparatuses other than a first nozzle and a second nozzle on a polishing table and can retract at least one of the first nozzle and the second nozzle from the polishing table at an arbitrary timing.SOLUTION: A liquid supply device includes: a first arm which has a first nozzle; a second arm which has a second nozzle; a first rotary shaft which supports a base end section of the first arm; a second rotary shaft which supports a base end section of the second arm; a first rotation driving section which turns the first arm from a fluid supply position up to a retracted position by rotating the first rotary shaft; a second rotation driving section which turns the second arm from the fluid supply position up to the retracted position by rotating the second rotary shaft; and a control section. The first rotary shaft and the second rotary shaft are arranged coaxially with each other. The control section can control an operation of the first rotation driving section and an operation of the second rotation driving section mutually independently.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In recent years, as semiconductor devices have become more highly integrated, circuit wiring has become finer and the distance between wiring has become narrower. In the manufacture of semiconductor devices, many types of materials are repeatedly deposited in film form on silicon wafers to form a layered structure. In order to form this layered structure, technology for flattening the wafer surface is important. As one method for flattening such wafer surfaces, polishing equipment (also known as chemical mechanical polishing equipment) that performs chemical mechanical polishing (CMP) is widely used.

[0003] A chemical mechanical polishing (CMP) apparatus generally comprises a polishing table with a polishing pad attached, a top ring (polishing head) that holds the wafer, and a slurry discharge nozzle that supplies a polishing liquid (slurry) onto the polishing pad. While the polishing liquid is supplied onto the polishing pad from the slurry discharge nozzle, the top ring presses the wafer against the polishing pad, and the top ring and polishing table are moved relative to each other to polish the wafer and flatten its surface.

[0004] After polishing a wafer, particles such as polishing debris and abrasive grains contained in the polishing liquid remain on the polishing pad. Therefore, after polishing the wafer, a mist of cleaning fluid (liquid or a mixture of liquid and gas) is sprayed onto the polishing pad from an atomizer having at least one spray nozzle that sprays liquid or a mixture of gas and liquid toward the polishing pad, thereby removing foreign matter from the polishing pad.

[0005] In conventional devices, when the slurry discharge nozzle was moved between the slurry dropping position and the retracted position, the slurry discharge nozzle attached to the tip of the swing arm interfered with the atomizer placed on the polishing pad, limiting the operating range of the swing arm and the height of the slurry discharge nozzle, making it difficult to dispense the slurry required for wafer polishing at the optimal timing and position.

[0006] Patent Document 1 discloses a technology in which a swing arm is configured to be rotatable around a horizontal axis extending horizontally, and when the slurry discharge nozzle is moved between a slurry drip position and a retracted position, the swing arm is rotated around the horizontal axis to retract the slurry discharge nozzle above the atomizer. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-6549 Summary of the Invention [Problem to be solved by the invention]

[0008] In addition to the slurry discharge nozzle and atomizer, space is required above the polishing pad of a polishing apparatus to install other devices such as a dresser for dressing the polishing pad and a temperature control slider for adjusting the surface temperature of the polishing pad. However, conventional apparatuses require a large space for the swing arm that swings over the polishing pad and for arranging devices such as the dresser and temperature control slider on the polishing pad, making it difficult to secure space for the atomizer to swing.

[0009] Furthermore, as mentioned above, in conventional devices, the slurry discharge nozzle at the tip of the swing arm interferes with the atomizer placed on the polishing pad, limiting the range of motion of the swing arm and making it difficult to drip the slurry required for wafer polishing at the optimal timing and position.

[0010] Furthermore, in conventional devices, unpredictable dripping of sprayed water (falling water droplets) after cleaning the polishing pad by an atomizer placed on the polishing pad could dilute the slurry supplied to the polishing pad during polishing, changing the amount of polishing per unit of slurry, which could lead to increased consumption of expensive slurry.

[0011] The present invention has been made in consideration of the above points, and an object of the present invention is to provide a liquid supply device and a polishing apparatus that can ensure space on the polishing table for installing devices other than the first nozzle and the second nozzle, and that can retract at least one of the first nozzle and the second nozzle from above the polishing table at any time. [Means for solving the problem]

[0012] A liquid supply device according to a first aspect of the present invention comprises: a first arm having a first nozzle for discharging a first fluid onto the polishing table; a second arm having a second nozzle for discharging a second fluid onto the polishing table; a first rotation shaft that supports a base end of the first arm; a second rotation shaft that supports a base end of the second arm; a first rotation drive unit that rotates the first rotation shaft about its axis to pivot the first arm from a fluid supply position inside the polishing table to a retracted position outside the polishing table; a second rotation drive unit that rotates the second rotation shaft about its axis to pivot the second arm from a fluid supply position inside the polishing table to a retracted position outside the polishing table; a control unit that controls operations of the first rotation drive unit and the second rotation drive unit; Equipped with The first rotating shaft and the second rotating shaft are arranged coaxially with each other, The control unit is capable of controlling the operation of the first rotary drive unit and the operation of the second rotary drive unit independently of each other.

[0013] According to this aspect, since the first rotation shaft and the second rotation shaft are arranged coaxially with each other and the first arm and the second arm rotate about the same axis, the space on the polishing table occupied by the rotation of the first arm and the second arm can be minimized, thereby making it possible to secure space on the polishing table for installing other devices in addition to the first nozzle and the second nozzle. Furthermore, since the operation of the first rotation drive unit and the operation of the second rotation drive unit can be controlled independently of each other, at least one of the first nozzle and the second nozzle can be retracted from the polishing table at any time by individually driving the first arm and the second arm. For example, if the first nozzle is a slurry discharge nozzle and the second nozzle is an atomizer, when the oscillating arm is oscillating to discharge slurry from the slurry discharge nozzle, by retracting the atomizer to the outside of the polishing table in advance, the operating range of the oscillating arm will not be restricted by interference with the atomizer, making it possible to drip the slurry onto the entire surface of the pad, and the slurry supplied onto the polishing pad will not be diluted by unpredictable dripping of water (falling water droplets) from the atomizer, thereby improving polishing performance.

[0014] A liquid supply apparatus according to a second aspect of the present invention is the liquid supply apparatus according to the first aspect, The first arm and the second arm are disposed at different height positions.

[0015] According to this aspect, the first arm and the second arm can be rotated so as to intersect with each other, so that both the first nozzle and the second nozzle can be retracted from above the polishing table at any timing.

[0016] A liquid supply device according to a third aspect of the present invention is the liquid supply device according to the first or second aspect, the first fluid is one or more of a polishing liquid, a chemical liquid, pure water, nitrogen, and compressed air; The second fluid is one or more of a polishing liquid, a chemical liquid, pure water, nitrogen, and compressed air.

[0017] A liquid supply device according to a fourth aspect of the present invention is the liquid supply device according to any one of the first to third aspects, the first nozzle has a plurality of outlets; and / or The second nozzle has a plurality of outlets.

[0018] A liquid supply device according to a fifth aspect of the present invention is the liquid supply device according to any one of the first to fourth aspects, The control unit is capable of controlling the ejection of the first fluid from the first nozzle and the ejection of the second fluid from the second nozzle independently of each other.

[0019] A liquid supply device according to a sixth aspect of the present invention is the liquid supply device according to any one of the first to fifth aspects, The control unit is capable of supplying a first fluid from the first nozzle regardless of the position of the first arm, and is capable of supplying a second fluid from the second nozzle regardless of the position of the second arm.

[0020] A liquid supply device according to a seventh aspect of the present invention is the liquid supply device according to any one of the first to sixth aspects, The control unit is capable of causing a first fluid to be ejected from the first nozzle while swinging the first arm, and / or is capable of causing a second fluid to be ejected from the second nozzle while swinging the second arm.

[0021] A polishing apparatus according to an eighth aspect of the present invention includes the liquid supply apparatus according to any one of the first to seventh aspects. [Effects of the Invention]

[0022] According to the present invention, space can be secured on the polishing table to install other equipment other than the first nozzle and the second nozzle, and at least one of the first nozzle and the second nozzle can be retracted from the polishing table at any time. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a plan view showing a schematic configuration of a polishing apparatus according to an embodiment. [Figure 2] 2 is an enlarged vertical cross-sectional view of a liquid supply device included in the polishing apparatus shown in FIG. [Figure 3] FIG. 3 is a plan view showing the arrangement of the first arm and the second arm when cleaning the table before and after polishing. [Figure 4] FIG. 4 is a plan view showing the arrangement of the first arm and the second arm during maintenance. [Figure 5] FIG. 5 is a side view showing the jetting angle of the second nozzle. [Figure 6] FIG. 6 is a plan view showing the arrangement of the second nozzles. [Figure 7] FIG. 7 is a plan view showing gaps (streaks) that occur between the second nozzles. [Figure 8] FIG. 8 is a flowchart showing an example of the operation of the polishing apparatus according to one embodiment. [Figure 9] FIG. 9 is a plan view showing a schematic configuration of a polishing apparatus of a comparative example. [Figure 10] FIG. 10 is a flowchart showing an example of the operation of the polishing apparatus of the comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals will be used for parts that can be configured identically, and duplicate descriptions will be omitted.

[0025] (Device configuration) FIG. 1 is a plan view showing a schematic configuration of a polishing apparatus 10 according to one embodiment.

[0026] As shown in FIG. 1, the polishing apparatus 10 includes a polishing table 2 on which a polishing pad (not shown) is attached, a top ring (polishing head) 3 for holding a wafer (not shown) and polishing the wafer while pressing it against the polishing pad on the polishing table 2, and a liquid supply device 10.

[0027] Of these, the top ring 3 is supported by a top ring head 4. A polishing pad (not shown) is affixed to the upper surface of the polishing table 2, and the upper surface of this polishing pad forms the polishing surface for polishing the wafer. Note that a fixed abrasive wheel can be used instead of the polishing pad. The top ring 3 and polishing table 2 are configured to be rotatable about their respective axes. The wafer is held by vacuum suction on the underside of the top ring 3. During polishing, a polishing liquid (slurry) is supplied from a liquid supply device 10 to the polishing surface of the polishing pad, and the wafer to be polished is pressed against the polishing surface by the top ring 3 and polished.

[0028] FIG. 2 is an enlarged vertical cross-sectional view of the liquid supply device 10. As shown in FIG.

[0029] As shown in Figures 1 and 2, the liquid supply device 10 has a first arm 11a and a second arm 11b, a first rotation shaft 13a and a second rotation shaft 13b, a first rotation drive unit 14a and a second rotation drive unit 14b, and a control unit 15.

[0030] Of these, the first arm 11a is disposed so as to extend horizontally above the polishing table 11, and the base end of the first arm 11a is fixed to and supported by a first rotation shaft 13a.

[0031] The first arm 11a has a first nozzle 12a that discharges a first fluid onto the polishing table 2. The first nozzle 12a may have multiple discharge ports. In this embodiment, the first nozzle 12a has four discharge ports. However, this is not limited to four, and the number may be one to three, or five or more. The number of discharge ports of the first nozzle 12a may be increased as long as the first nozzle 12a can discharge the first fluid onto the polishing table 2. In the illustrated example, the discharge port of the first nozzle 12a is positioned at the tip of the first arm 11a, and the first fluid supplied from a first fluid supply source (not shown) is sent to each discharge port of the first nozzle 12a via an openable / closable first valve 16a. The type of the first fluid is not particularly limited, and the first fluid may be one or more of abrasive liquid, chemical liquid, pure water, nitrogen, and compressed air, for example.

[0032] In the illustrated example, the first rotation drive unit 14a is provided at the lower end of the first rotation shaft 13a. The drive system of the first rotation drive unit 14a is not particularly limited, and the first rotation drive unit 14a may be, for example, a motor, an electric cylinder, an air cylinder, a hollow DD (direct drive) motor, or a hollow rotary actuator. The first rotation drive unit 14a rotates the first rotation shaft 13a about its vertical axis, thereby moving (rotating about the axis of the first rotation shaft 13a) the first arm 11a fixed to the first rotation shaft 13a from a fluid supply position defined inside the polishing table 2 to a retracted position defined outside the polishing table 2 in a plan view.

[0033] The second arm 11b is disposed so as to extend horizontally above the polishing table 11, and a base end of the second arm 11b is fixed to and supported by a second rotation shaft 13b.

[0034] The second arm 11b has a second nozzle 12b that discharges the second fluid onto the polishing table 2. The second nozzle 12b may have multiple discharge ports. In this embodiment, the number of discharge ports of the second nozzle 12b is eight, but this is not limited thereto and may be one to seven, or nine or more. The number of discharge ports of the second nozzle 12b may be increased as long as the second fluid can be discharged onto the polishing table 2. In the illustrated example, the discharge ports of the second nozzle 12b are arranged at equal intervals along the longitudinal direction of the second arm 11b. The second fluid supplied from a second fluid supply source (not shown) is sent to each discharge port of the second nozzle 12b via an openable / closable second valve 16b. The type of the second fluid is not particularly limited. For example, the second fluid may be one or more of abrasive liquid, chemical liquid, pure water, nitrogen, and compressed air.

[0035] In the illustrated example, the second rotation drive unit 14a is disposed adjacent to the lower end of the second rotation shaft 13b and is connected to the second rotation shaft 13b via a pulley and a belt. The drive system of the second rotation drive unit 14b is not particularly limited, and the second rotation drive unit 14b may be, for example, a motor, an electric cylinder, an air cylinder, a hollow DD (direct drive) motor, or a hollow rotary actuator. The second rotation drive unit 14b rotates the second rotation shaft 13b about its vertical axis, thereby moving (rotating) the second arm 11b fixed to the second rotation shaft 13b from a fluid supply position defined inside the polishing table 2 to a retracted position defined outside the polishing table 2 in a plan view (pivoting about the axis of the second rotation shaft 13b).

[0036] In this embodiment, the first nozzle 12a is a standard slurry discharge nozzle with four discharge ports, each discharging the abrasive liquid, pure water, and dispersant from a different discharge port. The second nozzle 12b is an atomizer with eight discharge ports, each discharging (spraying) pure water and nitrogen in sequence from each discharge port. The first nozzle 12a and the second nozzle 12b are not limited to a combination of a standard slurry discharge nozzle and an atomizer. As a variation, the first nozzle 12a may be a slurry multi-nozzle (multi-point liquid discharge nozzle) with eight discharge ports, and the second nozzle 12b may be an atomizer. For example, the technology described in Japanese Patent Application No. 2020-038725 filed by the present applicant may be applied as a slurry multi-nozzle (multi-point liquid discharge nozzle). As another variation, both the first nozzle 12a and the second nozzle 12b may be standard slurry discharge nozzles. As yet another modification, both the first nozzle 12a and the second nozzle 12b may be atomizers.

[0037] The first nozzle 12a and the second nozzle 12b may be configured to eject temperature-controlled fluids. As a first example, heated fluids (e.g., the first fluid is a warm polishing liquid (up to 80°C) and the second fluid is warm pure water (up to 80°C)) may be ejected from the first nozzle 12a and the second nozzle 12b to maintain a uniform temperature on the polishing table 2. In this case, a temperature control slider (not shown) or the like disposed on the polishing table 2 may be used in combination. For example, the technology disclosed in Japanese Patent Application Laid-Open No. 2018-030181 filed by the present applicant may be applied as the temperature control slider. A temperature sensor may be installed on the ceiling of the polishing chamber to monitor the temperature of the polishing table 2. The temperature control of the first fluid and the second fluid may be performed outside the polishing chamber.

[0038] As a second example, the temperature of the polishing table 2 may be prevented from rising by discharging cooling fluids (for example, the first and second fluids are both about 30°C or less) from the first nozzle 12a and the second nozzle 12b. In this case, a pad cooling nozzle (not shown) disposed on the polishing table 2 may also be used. As the pad cooling nozzle, for example, the technology disclosed in Japanese Patent Application Laid-Open No. 2018-030181 by the present applicant may be applied. As in the first example, a temperature sensor may be installed on the ceiling of the polishing chamber to monitor the temperature of the polishing table 2, and the temperature adjustment of the first and second fluids may be performed outside the polishing chamber.

[0039] In this embodiment, as shown in Figures 1 and 2, first rotating shaft 13a and second rotating shaft 13b are arranged coaxially with each other. In the illustrated example, first rotating shaft 13a is arranged coaxially inside second rotating shaft 13b, but this is not limited thereto, and second rotating shaft 13b may be arranged coaxially inside first rotating shaft 13a. In this specification, the phrase "first rotating shaft 13a and second rotating shaft 13b being arranged coaxially with each other" means, in other words, that the centers of rotation of first rotating shaft 13a and second rotating shaft 13b are the same.

[0040] As shown in FIG. 2, the first arm 11a and the second arm 11b may be disposed at different heights. In the illustrated example, the upper end of the first rotating shaft 13a protrudes upward and is exposed relative to the upper end of the second rotating shaft 13b, and the base end of the first arm 11a is fixedly supported by the upper end of the first rotating shaft 13a. This allows the first arm 11a to be disposed at a higher height than the second arm 11. As a modified example (not shown), the outer circumferential surface of the second rotating shaft 13b may be provided with a notch extending along the circumferential direction, and a portion of the outer circumferential surface of the first rotating shaft 13a may be exposed to the outside through the notch of the second rotating shaft 13b, and the base end of the first arm 11a may be fixedly supported by the outer circumferential surface of the first rotating shaft 13a through the notch of the second rotating shaft 13b. In this case, the first arm 11a is disposed at a lower height than the second arm 11.

[0041] The first and second rotary shafts 13a and 13b are arranged coaxially, so that the first and second arms 11a and 11b rotate about the same axis. This minimizes the space required for the rotation of the first and second arms 11a and 11b on the polishing table 2, and ensures space on the polishing table 2 for installing other devices (for example, a dresser (not shown), the temperature control slider, the pad cooling nozzle, etc.) other than the first and second nozzles 12a and 12b.

[0042] 2, the tip of the second arm 11b may be located inside the position of the first nozzle 12a (i.e., closer to the rotation axes 13a and 13b). In this case, the space in the height direction between the first nozzle 12a and the polishing table 2 can be omitted (i.e., there is no need to increase the height of the first nozzle 12a to avoid the second arm 11b).

[0043] Control unit 15 is composed of one or more computers, and can control the operation of first rotation drive unit 14a and the operation of second rotation drive unit 14b independently of each other (i.e., one operation regardless of whether the other is operating) by sending control signals to first rotation drive unit 14a and second rotation drive unit 14b, respectively. Control unit 15 may also be able to control the ejection of the first fluid from first nozzle 12a and the ejection of the second fluid from second nozzle 12b independently of each other (i.e., whether one is ejected from the other) by sending control signals to first valve 16a and second valve 16b, respectively.

[0044] The operation of the first rotary drive unit 14a and the operation of the second rotary drive unit 14b are controlled independently of each other, and the first arm 11a and the second arm 11b are driven separately, thereby enabling at least one of the first nozzle 12a and the second nozzle 12b to be retracted at any time from above the polishing table 2. For example, if the first nozzle 12a is a slurry discharge nozzle and the second nozzle 12b is an atomizer, by retracting the atomizer 12b from above the polishing table 2 in advance when discharging slurry from the slurry discharge nozzle 12a while swinging the first arm 11a, the operating range of the first arm 11a is not limited by interference with the atomizer 12b, allowing the slurry to be dripped onto the entire surface of the pad, and preventing the slurry supplied onto the polishing pad from being diluted by unpredictable dripping of water (falling water droplets) from the atomizer 12b, improving polishing performance.

[0045] In addition, in this embodiment, since the first arm 11a and the second arm 11b are disposed at different heights, when the first arm 11a and the second arm 11b are rotated around the same axis, the first arm 11a and the second arm 11b can be rotated so as to intersect with each other (i.e., one passes above (or below) the other). This allows either the first nozzle 12a or the second nozzle 12b to be retracted from above the polishing table 2 at any timing (i.e., one regardless of the position of the other).

[0046] The advantage of retracting the first nozzle 11a and the second nozzle 11b at any timing is as follows: In other words, it becomes possible to perform advance preparations for the following operations (1) to (5) at the retracted positions at any timing. (1) Discharge of fluid (e.g., slurry) remaining in the piping (2) Flushing (cleaning) the inside of the piping with pure water (3) Preloading of fluid (e.g., slurry) (preparatory operation to make the fluid ready to be discharged from the discharge port) (4) Cleaning of the nozzle tip (discharge port) and nozzle body by a cleaning means (not shown) provided in the retracted position (5) If the nozzle is an atomizer, use the atomizer to clean equipment in the retracted position (for example, equipment that becomes dirty with slurry that falls from the slurry nozzle when the slurry nozzle is retracted). Operations such as those described above in (1) to (5) were originally factors that reduced the polishing time (wafer processing time), but by retracting both the first nozzle 12a and the second nozzle 12b to the outside of the polishing table 2 at any time, it becomes possible to operate one nozzle during the idle time while the other nozzle is operating on the polishing table 2, thereby reducing the reduction in the polishing time (wafer processing time).

[0047] Fig. 3 is a plan view showing the arrangement of the first arm 11a and the second arm 12b during table cleaning before and after polishing in an embodiment in which the first nozzle 12a is a slurry discharge nozzle and the second nozzle 12b is an atomizer, and Fig. 4 is a plan view showing the arrangement of the first arm 11a and the second arm 12b during maintenance. As shown in Fig. 3, during table cleaning, the second arm 11b is positioned at a fluid discharge position inside the polishing table 2, and the first arm 11a is positioned at a retracted position outside the polishing table 2. Also, as shown in Fig. 4, during maintenance, both the first arm 11a and the second arm 11b are positioned at retracted positions outside the polishing table 2.

[0048] The control unit 15 may send a control signal to the first valve 16a to cause the first fluid to be supplied from the first nozzle 12a regardless of the position of the first arm 11a (i.e., even if the arm 11a is not at a predetermined liquid discharge position), and may send a control signal to the second valve 16b to cause the second fluid to be supplied from the second nozzle 12b regardless of the position of the second arm 11b (i.e., even if the arm 11b is not at a predetermined liquid discharge position). This allows the first nozzle 12a and the second nozzle 12b to discharge fluids at any desired timing. For example, if the first nozzle 12a is a slurry discharge nozzle and the second nozzle 12b is an atomizer, the second arm 11b may be positioned at a cleaning liquid discharge position inside the polishing table 2 to spray a cleaning liquid from the atomizer 12b to clean the polishing table 2, while the first arm 11b is positioned at a retracted position outside the polishing table 2 to spray a slurry from the slurry discharge nozzle 12a to perform preloading.

[0049] The control unit 15 may be capable of causing the first fluid to be ejected from the first nozzle 16a while swinging the first arm 11a, and / or may be capable of causing the second fluid to be ejected from the second nozzle 16b while swinging the second arm 11b.

[0050] With reference to FIGS. 5 to 7, when the second nozzle 12b is an atomizer, the advantages of discharging the second fluid from the atomizer 12b while swinging the second arm 11b will be described.

[0051] As shown in Fig. 5, each outlet of the atomizer 12b has a slit shape, and the second fluid ejected (sprayed) from each outlet spreads at an ejection angle θ3 and lands on the polishing table 2. Therefore, the landing area 17 of the second fluid on the polishing table 2 has an elongated shape, as shown in Fig. 6. Here, as shown in Fig. 5, each slit-shaped outlet is attached with its longitudinal direction D2 tilted by a nozzle angle θ1 (e.g., 30° to 60°) with respect to the longitudinal direction D1 of the second arm 11b so that the longitudinal ends of adjacent landing areas 17 overlap in the radial direction of the polishing table 2 when the second arm 11b is disposed at a predetermined fluid supply position. In this case, theoretically, when the second arm 11b is positioned at a predetermined fluid supply position, the longitudinal ends of adjacent water landing areas 17 overlap in the radial direction of the polishing table 2, making it possible to supply the second fluid to the entire surface of the rotating polishing table 2 (without any gaps).

[0052] However, in reality, when the pressure of the second fluid supplied to the atomizer 12b decreases, the spray angle θ3 of the second fluid sprayed (sprayed) from each outlet becomes narrower, and as a result, the length of each landing area 17 of the second fluid on the polishing table 2 becomes shorter, as shown in Figure 7.As a result, when the second arm 11b is positioned at a predetermined fluid supply position, the longitudinal ends of adjacent landing areas 17 no longer overlap in the radial direction of the polishing table 2 (gaps are created), and there is a possibility that streaks will remain on the rotating polishing table 2 where the second fluid is not supplied (streaks 18 will be created).

[0053] In contrast, in this embodiment, by ejecting the second fluid from the second nozzle (atomizer) 16b while swinging the second arm 11b at a swing angle θ2 (for example, 1 to 45°), it is possible to overlap the landing area 17 on the streak residue 18 even if the spray angle θ3 is narrow, and therefore it is possible to supply the second fluid to the entire surface of the polishing table 2 (without any gaps) and maintain full surface cleaning.

[0054] (Example of operation) Next, an example of the operation of polishing apparatus 1 will be described with reference to Fig. 8. Fig. 8 is a flowchart showing an example of the operation of polishing apparatus 1. In the following, an example will be described in which first nozzle 12a is a slurry discharge nozzle and second nozzle 12b is an atomizer.

[0055] First, when polishing a wafer W, as shown in FIG. 1, the second arm 11b is positioned at a retracted position outside the polishing table 2, and the first arm 11a is positioned at a fluid ejection position inside the polishing table 2. With this, the control unit 15 sends a control signal to the first valve 16a to eject slurry onto the polishing table 2 from the first nozzle (slurry ejection nozzle) 12b provided on the first arm 11a, and the wafer (not shown) to be polished is pressed onto the polishing table 2 by the top ring 3 and polished.

[0056] As shown in FIG. 8, after polishing the wafer W, the control unit 15 sends a control signal to the first valve 16a to stop the discharge of slurry from the first nozzle 12b, and then, based on information obtained from the first rotation drive unit 14a and the second rotation drive unit 14b, the control unit 15 simultaneously checks the positions of the first arm 11a and the second arm 11b, and determines whether it is possible to operate the first arm 11a and the second arm 11b (step S10).

[0057] If it is not possible to operate the first arm 11a and the second arm 11b (step S10: NO), the control unit 15 reconfirms the positions of the first arm 11a and the second arm 11b based on information obtained from the first rotation drive unit 14a and the second rotation drive unit 14b (step S10).

[0058] If it is possible to operate the first arm 11a and the second arm 11b (step S10: YES), the control unit 15 sends a control signal to the second rotation drive unit 14b to move (pivot) the second arm 11b from the retracted position to the fluid ejection position (step S11), and at the same time sends a control signal to the first rotation drive unit 14a to move (pivot) the first arm 11a from the fluid ejection position to the waiting position (step S13).

[0059] In this embodiment, first arm 11a and second arm 11b are configured to be rotatable about the same axis, and control unit 15 can independently control the operation of first rotation drive unit 14a and the operation of second rotation drive unit 14b. This eliminates the need to check the position of second arm 11b when rotating first arm 11a to prevent interference with second arm 11b, and eliminates the need to check the position of first arm 11a when rotating second arm 11b to prevent interference with first arm 11a. Therefore, the process (step S13) of moving (rotating) first arm 11a from the fluid discharge position to the retracted position and the process (step S11) of moving (rotating) second arm 11b from the retracted position to the fluid discharge position can be performed simultaneously. This simplifies the control sequence compared to a comparative example described later, and reduces the risk of interference between first arm 11a and second arm 11b.

[0060] Next, as shown in FIG. 3, the second arm 11b is positioned at a fluid ejection position inside the polishing table 2 (step S12), and the first arm 11a is positioned at a retracted position outside the polishing table 2 (step S14). Then, the control unit 15 sends a control signal to the second valve 16b to spray a cleaning liquid (e.g., pure water) onto the polishing table 2 from each outlet of the second nozzle (atomizer) 12a provided on the second arm 11b, thereby cleaning the polishing surface on the polishing table 2 (step S15).

[0061] In step S15, the control unit 15 may send a control signal to the second rotation drive unit 14b to swing the second arm 11b at a swing angle θ2 (for example, 1 to 45°). By spraying the second fluid from the second nozzle (atomizer) 16b while swinging the second arm 11b, even if the spray angle θ3 (see FIG. 5) is narrowed, it is possible to make the water landing area 17 overlap the streak residue 18 as shown in FIG. 7, and therefore it is possible to supply the second fluid to the entire surface of the polishing table 2 (without any gaps) and maintain full surface cleaning.

[0062] Thereafter, the control unit 15 sends a control signal to the second valve 16b to stop the spraying of the cleaning liquid from the second nozzle 12b, thereby completing the cleaning of the polishing surface of the polishing table 2 (step S16).

[0063] Next, the control unit 15 simultaneously checks the positions of the first arm 11a and the second arm 11b based on the information acquired from the first rotation drive unit 14a and the second rotation drive unit 14b, and determines whether it is possible to operate the first arm 11a and the second arm 11b (step S20).

[0064] If it is not possible to operate the first arm 11a and the second arm 11b (step S20: NO), the control unit 15 reconfirms the positions of the first arm 11a and the second arm 11b based on information obtained from the first rotation drive unit 14a and the second rotation drive unit 14b (step S20).

[0065] If it is possible to operate the first arm 11a and the second arm 11b (step S20: YES), the control unit 15 sends a control signal to the second rotation drive unit 14b to move (pivot) the second arm 11b from the fluid ejection position to the retracted position (step S21), and at the same time sends a control signal to the first rotation drive unit 14a to move (pivot) the first arm 11a from the retracted position to the fluid ejection position (step S23).

[0066] In this embodiment, first arm 11a and second arm 11b are configured to be rotatable about the same axis, and control unit 15 can independently control the operation of first rotation drive unit 14a and the operation of second rotation drive unit 14b. This eliminates the need to check the position of second arm 11b to prevent interference with first arm 11b when rotating first arm 11a, and eliminates the need to check the position of first arm 11a to prevent interference with first arm 11a when rotating second arm 11b. Therefore, the process (step S21) of moving (rotating) second arm 11b from the fluid discharge position to the retracted position and the process (step S23) of moving (rotating) first arm 11a from the retracted position to the fluid discharge position can be performed simultaneously. This simplifies the control sequence compared to a comparative example described later, and reduces the risk of interference between first arm 11a and second arm 11b.

[0067] Next, as shown in FIG. 1, the first arm 11a is positioned at a fluid ejection position inside the polishing table 2 (step S24), and the second arm 11b is positioned at a retracted position outside the polishing table 2 (step S22), and then the next wafer is polished.

[0068] (Comparative Example) Next, as a comparative example, the operation of polishing apparatus 100 will be described in which first rotating shaft 113a and second rotating shaft 113b are not coaxially arranged (arranged at different positions from each other) as shown in Fig. 9. Fig. 10 is a flowchart showing an example of the operation of polishing apparatus 100 of the comparative example.

[0069] First, when polishing a wafer W, as shown in FIG. 9, the first arm 11a is positioned at a fluid ejection position inside the polishing table 2, and slurry is ejected onto the polishing table 102 from a slurry ejection nozzle (not shown) provided on the first arm 11a, and the wafer (not shown) to be polished is pressed onto the polishing table 102 by the top ring 103 and polished.

[0070] As shown in FIG. 10, after polishing the wafer W, the discharge of slurry from the slurry discharge nozzle provided on the first arm 111a is stopped, and then the position of the second arm 111b is checked to determine whether the first arm 111a can be retracted without interfering with the second arm 111b (step S110a).

[0071] If it is not possible to retract the first arm 111a without interfering with the second arm 111b (step S110a: NO), the position of the second arm 111b is reconfirmed (step S110a).

[0072] If it is possible to retract the first arm 111a without interfering with the second arm 111b (step S110a: YES), the first arm 111a is rotated around the axis of the first rotating shaft 113a and moved from the slurry discharge position to the retracted position (step S113).

[0073] Next, after the first arm 111a is positioned at a retracted position outside the polishing table 2 (step S114), the position of the first arm 111a is confirmed, and it is determined whether the second arm 111b can be moved to the cleaning liquid ejection position without interfering with the first arm 111a (step S110b).

[0074] If it is not possible to move the second arm 111b without interfering with the first arm 111a (step S110b: NO), the position of the first arm 111a is reconfirmed (step S110a).

[0075] If it is possible to move the second arm 111b without interfering with the first arm 111a (step S110b: YES), the second arm 111b is rotated around the axis of the second rotating shaft 113b and moved from the retracted position to the cleaning liquid ejection position (step S111).

[0076] Next, the second arm 111b is positioned at a cleaning liquid ejection position inside the polishing table 2 (step S112), and then cleaning liquid (e.g., pure water) is ejected onto the polishing table 102 from each ejection port of the atomizer provided on the second arm 111b, thereby cleaning the polishing surface on the polishing table 102 (step S115).

[0077] Thereafter, the atomizer provided on the second arm 111b stops spraying the cleaning liquid, and cleaning of the polishing surface of the polishing table 2 is completed (step S116).

[0078] Next, the position of the first arm 111a is confirmed, and it is determined whether or not the second arm 111b can be retracted without interfering with the first arm 111a (step S120a).

[0079] If it is not possible to retract the second arm 111b without interfering with the first arm 111a (step S120a: NO), the position of the first arm 111a is reconfirmed (step S110a).

[0080] If it is possible to retract the second arm 111b without interfering with the first arm 111a (step S120a: YES), the second arm 111b is rotated around the axis of the second rotation shaft 113b and moved from the cleaning liquid discharge position to the retracted position (step S121).

[0081] Next, after the second arm 111b is positioned at a retracted position outside the polishing table 2 (step S122), the position of the second arm 111b is confirmed, and it is determined whether the first arm 111a can be moved to the slurry ejection position without interfering with the second arm 111b (step S120b).

[0082] If it is not possible to move the first arm 111a without interfering with the second arm 111b (step S120b: NO), the position of the second arm 111b is reconfirmed (step S110a).

[0083] If it is possible to move the first arm 111a without interfering with the second arm 111b (step S120b: YES), the first arm 111a is rotated around the axis of the first rotating shaft 113a and moved from the retracted position to the slurry discharge position (step S123).

[0084] Next, the second arm 111b is positioned at the slurry discharge position inside the polishing table 2 (step S124), and then the next wafer is polished.

[0085] As described above, according to this embodiment, as shown in Figures 1 and 2, the first rotating shaft 13a and the second rotating shaft 13b are arranged coaxially with each other, and the first arm 11a and the second arm 11b rotate around the same axis, so that the space occupied by the rotation of the first arm 11a and the second arm 11b on the polishing table 2 can be minimized, thereby making it possible to secure space on the polishing table 2 for installing other equipment (for example, a dresser, a temperature control slider, a pad cooling nozzle, etc.) other than the first nozzle 11a and the second nozzle 11b.

[0086] Furthermore, according to this embodiment, the operation of the first rotary drive unit 14a and the operation of the second rotary drive unit 14b can be controlled independently of each other, and therefore, by separately driving the first arm 11a and the second arm 11b, at least one of the first nozzle 12a and the second nozzle 12b can be retracted at any timing from above the polishing table 2. For example, if the first nozzle 12a is a slurry discharge nozzle and the second nozzle 12b is an atomizer, when discharging slurry from the slurry discharge nozzle 12a while swinging the swing arm 11a, by retracting the atomizer 12b to the outside of the polishing table 2 in advance, the operating range of the swing arm 11a is not limited by interference with the atomizer 12b, making it possible to drip the slurry onto the entire surface of the pad, and preventing the slurry supplied onto the polishing pad from being diluted by unpredictable dripping of water (falling water droplets) from the atomizer 12b, thereby improving polishing performance.

[0087] Furthermore, according to this embodiment, since the first arm 11a and the second arm 11b are disposed at different heights, the first arm 11a and the second arm 11b can be rotated so as to intersect with each other (i.e., one passes above (or below) the other). This allows both the first nozzle 12a and the second nozzle 12b to be retracted from the polishing table 2 at any time (i.e., one regardless of the position of the other). By retracting both the first nozzle 12a and the second nozzle 12b to the outside of the polishing table 2 at any time, it becomes possible to use the idle time for preparatory operations (e.g., discharging fluid (e.g., slurry) remaining in the piping) that originally reduced the polishing time (wafer processing time). This reduces the reduction in the polishing time (wafer processing time).

[0088] Although the embodiments and modifications of the present invention have been described above by way of example, the scope of the present invention is not limited to these, and modifications and variations can be made according to the purpose within the scope of the claims. Furthermore, the embodiments and modifications can be combined as appropriate within the scope of the processing content. [Explanation of symbols]

[0089] 1 Polishing equipment 2 Polishing table 3 Top Ring 4 Top Ring Head 10 Liquid supply device 11a First Arm 11b Second Arm 12a No. 1 nozzle 12b Second nozzle 13a First rotation axis 13b Second rotation axis 14a First rotary drive unit 14b Second rotary drive unit 15 Control Unit 16a First valve 16b Second valve 17 Water landing area 18 Remaining muscles

Claims

1. a first arm having a first nozzle for discharging a first fluid onto the polishing table; a second arm having a second nozzle for discharging a second fluid onto the polishing table; a first rotation shaft that supports a base end of the first arm; a second rotation shaft supporting a base end of the second arm; a first rotation drive unit that rotates the first rotation shaft about its axis to pivot the first arm from a fluid supply position inside the polishing table to a retracted position outside the polishing table; a second rotation drive unit that rotates the second rotation shaft about its axis to pivot the second arm from a fluid supply position inside the polishing table to a retracted position outside the polishing table; a control unit that controls operations of the first rotation drive unit and the second rotation drive unit; Equipped with the first rotation shaft and the second rotation shaft are arranged coaxially with each other, The control unit is capable of controlling the operation of the first rotation drive unit and the operation of the second rotation drive unit independently of each other. A liquid supply device characterized by:

2. The first arm and the second arm are disposed at different height positions.

2. The liquid supply device according to claim 1.

3. the first fluid is one or more of a polishing liquid, a chemical liquid, pure water, nitrogen, and compressed air; the second fluid is one or more of a polishing liquid, a chemical liquid, pure water, nitrogen, and compressed air; 3. The liquid supply device according to claim 1, wherein the liquid supply device is a liquid supplying device.

4. the first nozzle has a plurality of outlets; and / or the second nozzle has a plurality of outlets; 4. The liquid supply device according to claim 1, wherein the liquid supply device is a liquid supplying device.

5. the control unit is capable of controlling the ejection of the first fluid from the first nozzle and the ejection of the second fluid from the second nozzle independently of each other.

5. The liquid supply device according to claim 1, wherein the liquid supply device is a liquid supplying device.

6. the control unit is capable of supplying a first fluid from the first nozzle regardless of a position of the first arm, and is capable of supplying a second fluid from the second nozzle regardless of a position of the second arm.

6. The liquid supply device according to claim 1, wherein the liquid supply device is a liquid supplying device.

7. the control unit is capable of discharging a first fluid from the first nozzle while swinging the first arm, and / or is capable of discharging a second fluid from the second nozzle while swinging the second arm.

7. The liquid supply device according to claim 1, wherein the liquid supply device is a liquid supplying device.

8. A polishing apparatus comprising the liquid supply apparatus according to any one of claims 1 to 7.

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