Substrate processing apparatus and substrate processing method

Abstract

This substrate processing apparatus comprises: a substrate holding unit that holds a substrate; a drive mechanism that drives a tool for processing the substrate being held by the substrate holding unit; a housing in which the substrate holding unit and the tool are housed; and a sprayer that sprays a mist of liquid into the housing.

Description

Technical Field

[0007]

[0001] The present disclosure relates to a substrate processing apparatus and a substrate processing method.

Background Art

[0002] The planar processing apparatus described in Patent Document 1 has a housing that houses a chuck and an index table, and grinds a substrate with a grindstone while supplying grinding fluid to the substrate inside the housing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] One aspect of the present disclosure provides a technique for suppressing the adhesion of dirt inside the housing.

Means for Solving the Problems

[0005] A substrate processing apparatus according to one aspect of the present disclosure includes a substrate holding unit that holds a substrate, a drive mechanism that drives a tool for processing the substrate held by the substrate holding unit, a housing that houses the substrate holding unit and the tool, A nozzle for supplying processing fluid between the tool and the substrate, and a sprayer that sprays a liquid in a mist form inside the housing. When viewed from vertically above, the sprayer atomizes the liquid toward the tool in a mist-like manner in a direction tangential to the outer circumference of the tool.

Effects of the Invention

[0006] According to one aspect of the present disclosure, it is possible to suppress the adhesion of dirt inside the housing.

Brief Description of the Drawings

[0007] [Figure 1] FIG. 1 is a plan view showing a substrate processing apparatus according to an embodiment. <0 [Figure 2] Figure 2 is a cross-sectional view showing an example of a drive mechanism. [Figure 3] Figure 3 is an enlarged cross-sectional view of a portion of Figure 2. [Figure 4] Figure 4 is a plan view showing an example of a sprayer. [Modes for carrying out the invention]

[0008] Embodiments of this disclosure will be described below with reference to the drawings. In each drawing, the same or corresponding components are denoted by the same reference numerals, and their descriptions may be omitted. In this specification, the X-axis, Y-axis, and Z-axis directions are perpendicular to each other. The X-axis and Y-axis directions are horizontal, and the Z-axis direction is vertical.

[0009] Referring to Figure 1, a substrate processing apparatus 1 according to one embodiment will be described. The substrate processing apparatus 1 grinds a substrate W, for example. Grinding includes polishing. The substrate processing apparatus 1 includes, for example, a rotary table 10, four chucks 20 for holding the substrate W, three drive mechanisms 30 for driving a tool D for processing the substrate W, a housing 80 that houses the chucks 20 and the tool D, and a control device 90.

[0010] The rotary table 10 holds four chucks 20 at equal intervals around the rotational centerline R1 and rotates around the rotational centerline R1. Each of the four chucks 20 rotates with the rotary table 10 and moves in the following order: loading / unloading position A0, first processing position A1, second processing position A2, third processing position A3, and back to loading / unloading position A0.

[0011] The loading / unloading position A0 serves as both the loading and unloading position for the substrate W. In this embodiment, the loading and unloading positions are the same, but they may be different positions.

[0012] The first machining position A1 is where primary machining (e.g., primary grinding) is performed. The second machining position A2 is where secondary machining (e.g., secondary grinding) is performed. The third machining position A3 is where tertiary machining (e.g., tertiary grinding) is performed.

[0013] The four chucks 20 are mounted on the rotary table 10 so as to be rotatable around their respective rotational centerlines R2 (see Figure 2). At the first machining position A1, the second machining position A2, and the third machining position A3, the chucks 20 rotate around their respective rotational centerlines R2.

[0014] One drive mechanism 30 performs primary processing on the substrate W at the first processing position A1. Another drive mechanism 30 performs secondary processing on the substrate W at the second processing position A2. The remaining drive mechanism 30 performs tertiary grinding on the substrate W at the third processing position A3.

[0015] The housing 80 prevents processing debris and processing fluid from scattering to the outside. Processing debris consists of powder or fragments generated by processing the substrate W. The powder includes powder scraped from the substrate W and abrasive particles detached from the tool D. The processing fluid is pure water, such as DIW (Deionized Water). The processing fluid enters between the tool D and the substrate W, reducing frictional resistance and frictional heat. The processing fluid is supplied by the nozzle 50 (see Figure 2).

[0016] The housing 80 has a top panel 81 located above the chuck 20 and a side panel 82 located to the side of the chuck 20. The top panel 81 is horizontal, and the side panel 82 is vertical. The top panel 81 is located above the side panel 82. The top panel 81 is provided with a passage opening 81a (see Figure 2) through which a tool D or the like passes.

[0017] As shown by the dashed line in Figure 1, the top panel 81 covers, for example, the area above the first processing position A1, the second processing position A2, and the third processing position A3. The top panel 81 also leaves the area above the loading / unloading position A0 open. For example, when viewed from above, the top panel 81 has a shape in which one corner of a rectangle is cut out in an L-shape.

[0018] The interior of the housing 80 is partitioned into a plurality of rooms by partition walls 83. The partition walls 83 are fixed to the lower surface of the upper panel 81. The partition walls 83 are provided, for example, in a cross shape. The partition walls 83 partition, for example, the loading / unloading position A0, the first processing position A1, the second processing position A2, and the third processing position A3.

[0019] The control device 90 is, for example, a computer and includes an arithmetic unit 91 such as a CPU (Central Processing Unit) and a storage unit 92 such as a memory. A program for controlling various processes executed in the substrate processing apparatus 1 is stored in the storage unit 92. The control device 90 controls the operation of the substrate processing apparatus 1 by causing the arithmetic unit 91 to execute the program stored in the storage unit 92.

[0020] The substrate processing apparatus 1 grinds one side of the substrate W, but may grind both sides of the substrate W.

[0021] The substrate processing apparatus 1 is not limited to a grinding apparatus. The substrate processing apparatus 1 may be a cutting apparatus or the like. When the substrate processing apparatus 1 is a grinding apparatus, a grinding wheel or the like is used as the tool D. When the substrate processing apparatus 1 is a cutting apparatus, an end mill or the like is used as the tool D.

[0022] <000,0097>Next, an example of the drive mechanism 30 will be described with reference to FIG. 2. The drive mechanism 30 rotates and raises and lowers the tool D. The drive mechanism 30 includes a movable part 31 to which the tool D is attached. The tool D is pressed against the substrate W to process the substrate W. The tool D includes, for example, a disk-shaped grinding wheel D1 and a plurality of grinding stones D2 arranged in a ring shape on the lower surface of the grinding wheel D1.

[0023] The movable part 31 has a motor 32, a vertical spindle shaft 33 rotated by the motor 32, and a flange 34 provided at the lower end of the spindle shaft 33. The flange 34 is arranged horizontally, and the tool D is attached to its lower surface. The motor 32 rotates the spindle shaft 33 to rotate the tool D attached to the flange 34. The rotation center line R3 of the tool D is the rotation center line of the spindle shaft 33.

[0024] The drive mechanism 30 further includes a lifting unit 35 for raising and lowering the movable part 31. The lifting unit 35 includes, for example, a vertical Z-axis guide 36, a Z-axis slider 37 that moves along the Z-axis guide 36, and a Z-axis motor 38 that moves the Z-axis slider 37. A motor 32 is fixed to the Z-axis slider 37 via a motor holder 39.

[0025] Next, an example of the spindle cover 40 will be described, mainly with reference to Figure 3. The drive mechanism 30 includes a spindle cover 40 that surrounds the spindle shaft 33. The spindle cover 40 prevents machining debris and machining fluid from adhering to the spindle shaft 33 and the upper surface of the flange 34.

[0026] The spindle cover 40 is fastened to the motor holder 39 with bolts 41 or the like and is raised and lowered together with the motor 32. The spindle cover 40 has a first cylindrical portion 51, an upper flange 52 provided at the upper end of the first cylindrical portion 51, and an intermediate flange 53 provided between the upper and lower ends of the first cylindrical portion 51. The upper flange 52 is fastened to the motor holder 39 with bolts 41 or the like. The upper flange 52 and the intermediate flange 53 are integrated with the first cylindrical portion 51.

[0027] The spindle cover 40 has a second cylindrical portion 62 surrounding the first cylindrical portion 51, and a ring-shaped top plate portion 64 that closes the internal space 63 formed between the first cylindrical portion 51 and the second cylindrical portion 62 from above. The top plate portion 64 is integrated with the second cylindrical portion 62 and is detachably connected to the lower surface of the intermediate flange 53 with bolts or the like. The intermediate flange 53 is optional, and the top plate portion 64 may be integrated with the first cylindrical portion 51. The top plate portion 64 is provided between the upper and lower ends of the first cylindrical portion 51.

[0028] The outer diameter of the first cylindrical portion 51 is smaller than the outer diameter of the flange 34. The lower end of the first cylindrical portion 51 is positioned above the upper surface of the flange 34 so as not to come into contact with the upper surface of the flange 34.

[0029] The second cylindrical portion 62 is positioned outside the first cylindrical portion 51 and surrounds the flange 34. The inner diameter of the second cylindrical portion 62 is larger than the outer diameter of the flange 34. The second cylindrical portion 62 extends below the upper surface of the flange 34. The second cylindrical portion 62 prevents machining debris from adhering to the upper surface of the flange 34.

[0030] The head 12 of the bolt 11 is provided on the upper surface of the flange 34. The head 12 of the bolt 11 is positioned in the internal space 63. The head 12 of the bolt 11 protrudes from the upper surface of the flange 34. A recess for accommodating the head 12 of the bolt 11 may be provided on the upper surface of the flange 34.

[0031] The worker attaches and detaches tool D by tightening or loosening bolt 11. A working hole, such as a hexagonal socket 13, is formed in the head 12 of bolt 11. The worker inserts the tip of a hex wrench into the hexagonal socket 13 and rotates the head 12 of bolt 11 to tighten or loosen bolt 11.

[0032] The spindle cover 40 prevents machining debris from adhering to the upper surface of the flange 34. This prevents the operator from getting dirty when attaching or detaching the tool D. It also prevents machining debris from accumulating in the hexagonal hole 13 of the bolt 11, and prevents the hexagonal hole 13 from becoming clogged with machining debris.

[0033] The inventors of this application investigated the cause of machining debris entering the internal space 63 of the spindle cover 40 using airflow simulations and other methods. When the motor 32 rotates the spindle shaft 33, the flange 34 rotates. They found that a rotational airflow is generated as if dragged by the rotation of the flange 34 or the head 12 of the bolt 11, and that negative pressure is generated in a part of the internal space 63. Furthermore, they found that if there is an obstacle (not shown) in the internal space 63, the turbulence of the rotational airflow increases, and the negative pressure generated in the internal space 63 increases.

[0034] In this embodiment, an intake port 66 is provided in the spindle cover 40 to draw gas (e.g., air) from the external space 65 into the internal space 63. The intake port 66 is located on the top plate portion 64 or the upper part of the second cylindrical portion 62 (top plate portion 64 in Figure 3). The intake port 66 draws gas from the external space 65 into the internal space 63 due to the pressure difference between the external space 65 and the internal space 63.

[0035] Even if the rotational airflow becomes turbulent in the internal space 63 of the spindle cover 40 and negative pressure is generated in a part of the internal space 63, the intake port 66 draws gas into the internal space 63, forming a downward or diagonally downward airflow at the lower end of the internal space 63, thereby limiting the entry of processing debris into the internal space 63. Furthermore, a downflow can be formed near the passage port 81a of the upper panel 81, suppressing the leakage of the atomized liquid described later through the passage port 81a.

[0036] The intake port 66 draws gas into the internal space 63 from the external space 65 above the top panel 81 of the housing 80. Clean gas can be drawn into the internal space 63. In order to draw in the cleanest gas possible, it is preferable that the intake port 66 be provided as high as possible, and it is preferable that the intake port 66 be provided on the top plate portion 64.

[0037] Multiple intake ports 66 are provided, for example, at intervals in the circumferential direction of the top plate portion 64. The multiple intake ports 66 may be provided at unequal pitches, but it is preferable that they be provided at equal pitches. By providing the multiple intake ports 66 at equal pitches, gas can be drawn into the internal space 63 evenly.

[0038] An intermediate flange 53 is placed on the top plate portion 64, where the intake port 66 is provided. A communication hole 56 is provided in the intermediate flange 53 at a position that overlaps with the intake port 66. Gas is drawn into the internal space 63 from the external space 65 through the communication hole 56 and the intake port 66. A notch (not shown) may be formed in the intermediate flange 53 to avoid the intake port 66.

[0039] Next, an example of the sprayer 70 will be described, mainly with reference to Figure 4. The substrate processing apparatus 1 is equipped with a sprayer 70 that sprays liquid in a mist form into the inside of the housing 80. The sprayer 70 can suppress drying inside the housing 80 and suppress the adhesion of dirt such as processing debris. In addition, by spraying the liquid in a mist form, the amount of liquid used can be reduced. The liquid to be sprayed is not particularly limited, but preferably the same liquid as the processing fluid (for example, DIW) is used.

[0040] The sprayer 70 preferably includes a two-fluid nozzle. The two-fluid nozzle atomizes the liquid using gas pressure and sprays it. By atomizing the liquid, the amount of liquid used can be further reduced. Also, by atomizing the liquid, the droplets can be made lighter, the dropping of droplets in the gas can be suppressed, and the droplets can be evenly distributed throughout the inside of the housing 80.

[0041] The sprayers 70 are installed, for example, at the first processing position A1, the second processing position A2, and the third processing position A3 (see Figure 1). This suppresses the adhesion of dirt such as processing debris at each of the first processing position A1, the second processing position A2, and the third processing position A3. The sprayers 70 are not installed at the loading / unloading position A0, which is not covered by the top panel 81.

[0042] The sprayer 70 sprays liquid in a mist form into the inside of the housing 80, for example, between the power-on of the substrate processing apparatus 1 and the start of processing of the substrate W, or between the completion of processing of one substrate W and the start of processing of another substrate W. The liquid can be allowed to soak into the tool D before processing of the substrate W begins, thereby reducing variations in processing quality between substrates W.

[0043] During the processing of the circuit board W, the processing fluid is scattered inside the housing 80, and the inside of the housing 80 is wet, so the sprayer 70 does not spray any liquid. However, the sprayer 70 may spray liquid during the processing of the circuit board W.

[0044] As shown in Figure 4, it is preferable that the tool D is rotated when the sprayer 70 sprays the liquid. A rotational airflow is generated as the tool D rotates. This rotational airflow allows the atomized liquid to spread throughout the entire interior of the housing 80 in a short time. Note that the spraying of the liquid and the rotation of the tool D do not have to occur simultaneously; for example, they may occur alternately. If the spray line of the sprayer 70 is offset from the rotation centerline R3 of the tool D when viewed from vertically above, it is also possible to rotate the tool D by the liquid colliding with it.

[0045] It is preferable that the chuck 20 is rotated when the sprayer 70 sprays liquid. A rotational airflow is generated as it is pulled along by the rotation of the chuck 20. This rotational airflow allows the atomized liquid to spread throughout the entire interior of the housing 80 in a short time. Note that the spraying of the liquid and the rotation of the chuck 20 do not have to be performed simultaneously; for example, they may be performed alternately.

[0046] When viewed from vertically above, it is preferable that the rotation direction of the tool D and the rotation direction of the chuck 20 are in the same direction (clockwise in Figure 4). This suppresses collisions between the rotational airflow caused by the rotation of the tool D and the rotational airflow caused by the rotation of the chuck 20, suppresses turbulence in the airflow, and allows the atomized liquid to spread evenly throughout the entire interior of the housing 80.

[0047] When viewed from vertically above, the tool D is rotated in a predetermined direction, and the sprayer 70 atomizes the liquid downstream of the tool D in the direction of rotation, using the straight line L0 connecting the rotational centerline R3 of the tool D and the nozzle 71 of the sprayer 70 as a reference. The liquid can be atomized without going against the rotational airflow caused by the rotation of the tool D.

[0048] When viewed from vertically above, the sprayer 70 is positioned outside the chuck 20 and tool D, and sprays the liquid in a mist toward the tool D. By directing the spray line of the sprayer 70 toward the tool D, the liquid can be easily spread over the tool D. In particular, if the liquid is sprayed onto the tool D while it is rotating, it is possible to spread the liquid over the entire circumference of the tool D. When viewed from vertically above, it is preferable that the sprayer 70 sprays the liquid in a mist in the tangential direction of the outer circumference of the tool D.

[0049] It is preferable that the sprayer 70 sprays the liquid in a mist from diagonally below the tool D towards the tool D (see Figure 2). This allows a wide area of ​​the tool D to be enveloped in the mist of liquid. Alternatively, the sprayer 70 can also spray the liquid in a mist from directly below the tool D towards the tool D.

[0050] Tool D includes, for example, a grinding wheel D2. The grinding wheel D2 has, for example, abrasive grains and a vitrified bond that binds the abrasive grains together. The vitrified bond is susceptible to degradation by liquids. By spraying the liquid in a mist form, the amount of liquid used can be reduced, and the degradation of the vitrified bond can be suppressed. The abrasive grains are not particularly limited, but for example, diamond abrasive grains.

[0051] The substrate processing apparatus 1 includes a discharge unit 72 that discharges gas from inside the housing 80 to the outside of the housing 80. The discharge unit 72 maintains a negative pressure inside the housing 80 relative to the outside of the housing 80, thereby limiting the leakage of processing debris and processing fluid.

[0052] The discharge section 72 is provided, for example, at the first processing position A1, the second processing position A2, and the third processing position A3 (see Figure 1). This suppresses the leakage of processing debris and processing fluid at each of the first processing position A1, the second processing position A2, and the third processing position A3. The discharge section 72 is not provided at the loading / unloading position A0, which is not covered by the top panel 81.

[0053] When viewed from vertically above, the tool D is rotated in a predetermined direction, and gas is discharged into the discharge section 72 from the upstream side in the direction of rotation of the tool D, using the straight line L1 connecting the rotational centerline R3 of the tool D and the discharge port 73 of the discharge section 72 as a reference. Gas can be discharged without going against the rotational airflow caused by the rotation of the tool D.

[0054] Next, an example of the cleaning solution nozzle 74 will be described with reference to Figure 2. The cleaning solution nozzle 74 discharges cleaning solution toward the spindle cover 40, the housing 80, or the tool D. According to this embodiment, the sprayer 70 suppresses the adhesion of dirt, so the cleaning solution nozzle 74 can efficiently wash away the dirt.

[0055] The cleaning solution nozzle 74 may be fixed or it may rotate like a sprinkler. In the latter case, it is possible to wash away all the dirt from the spindle cover 40, the housing 80, and the tool D with a single cleaning solution nozzle 74.

[0056] The cleaning solution nozzles 74 are provided, for example, at the first processing position A1, the second processing position A2, and the third processing position A3. Dirt can be washed away at each of the first processing position A1, the second processing position A2, and the third processing position A3. The cleaning solution nozzles 74 are not provided at the loading / unloading position A0, which is not covered by the top panel 81.

[0057] The cleaning solution nozzle 74 discharges cleaning solution, for example, between the end of processing one substrate W and the start of processing another substrate W. After processing the substrate W, any dirt that adhered to the substrate W during processing can be washed away.

[0058] During the processing of the substrate W, processing debris scatters inside the housing 80, and supplying cleaning fluid is wasteful, so the cleaning fluid nozzle 74 does not discharge cleaning fluid. However, the cleaning fluid nozzle 74 may discharge cleaning fluid during the processing of the substrate W.

[0059] The substrate processing apparatus and substrate processing method described above are not limited to the embodiments described herein. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These also naturally fall within the technical scope of this disclosure.

[0060] This application claims priority based on Japanese Patent Application No. 2022-147678, filed with the Japan Patent Office on September 16, 2022, and the entire contents of Japanese Patent Application No. 2022-147678 are incorporated herein by reference. [Explanation of Symbols]

[0061] 1. Substrate processing apparatus 20 Chuck (substrate holding part) 70 sprayer 80 cabinets D Tool W board

Claims

1. A substrate holding section that holds the substrate, A drive mechanism for driving a tool for processing the substrate held in the substrate holding portion, The substrate holding portion and the housing for housing the tool, A nozzle for supplying processing fluid between the tool and the substrate, A sprayer that atomizes liquid into the interior of the housing, Equipped with, A substrate processing apparatus in which, when viewed from vertically above, the sprayer sprays the liquid in a mist-like manner toward the tool in a direction tangential to the outer circumference of the tool.

2. The substrate processing apparatus according to claim 1, wherein the sprayer sprays the liquid in a mist form toward the tool from diagonally below the tool.

3. The substrate processing apparatus according to claim 1 or 2, wherein, when viewed from vertically above, the tool is rotated in a predetermined direction, and the sprayer atomizes the liquid downstream of the tool in the direction of rotation, with respect to a straight line connecting the rotational centerline of the tool and the nozzle of the sprayer.

4. The substrate processing apparatus according to claim 1 or 2, wherein, when viewed from vertically above, the tool and the substrate holding part are rotated in the same predetermined direction, and the sprayer sprays the liquid in a mist on the downstream side in the rotational direction of the tool, with reference to a straight line connecting the rotational center line of the tool and the nozzle of the sprayer.

5. The drive mechanism comprises a motor, a vertical spindle shaft rotated by the motor, and a spindle cover surrounding the spindle shaft. The housing has a top panel provided with a passage for the tool to pass through, The spindle cover has a first cylindrical portion surrounding the spindle shaft, a second cylindrical portion surrounding the first cylindrical portion, and a ring-shaped top plate portion that closes the internal space formed between the first cylindrical portion and the second cylindrical portion from above. The substrate processing apparatus according to claim 1 or 2, wherein the spindle cover is provided with an intake port for taking in gas from an external space above the upper panel into the internal space.

6. The drive mechanism comprises a motor, a vertical spindle shaft rotated by the motor, and a spindle cover surrounding the spindle shaft. The substrate processing apparatus according to claim 1 or 2, further comprising a cleaning liquid nozzle provided inside the housing for discharging cleaning liquid toward the spindle cover, the housing, or the tool.

7. A substrate processing method comprising processing a substrate using a substrate processing apparatus described in claim 1 or 2.

8. The substrate processing method according to claim 7, further comprising spraying the liquid in a mist form into the inside of the housing with the sprayer between the time the power is turned on and the time the processing of the substrate begins, or between the time the processing of one substrate is completed and the time the processing of another substrate begins.

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