Cleaning apparatus and cleaning method

Abstract

It is possible to determine whether or not the cleaning brush is in contact with the wafer. [Solution] The cleaning apparatus 1 comprises a plurality of support rollers that support the outer edge of the wafer, a cleaning brush 22-1 fixed to a support arm 24-1 for cleaning the surface side of the wafer, a cleaning brush 22-2 fixed to a support arm 24-2 for cleaning the back side of the wafer, a moving unit 25-1 that moves the cleaning brush 22-1 to a contact position where it contacts the surface side of the wafer and a retracted position, a moving unit 25-2 that moves the cleaning brush 22-2 to a contact position where it contacts the back side of the wafer and a retracted position, a cleaning fluid supply unit that supplies cleaning fluid to the surface side and the back side of the wafer, a displacement meter 26-1 that detects the displacement of the cleaning brush 22-1 relative to the support arm 24-1, and a displacement meter 26-2 that detects the displacement of the cleaning brush 22-2 relative to the support arm 24-2.

Description

Technical Field

[0001] The present invention relates to a cleaning device and a cleaning method.

Background Art

[0002] In the manufacturing process of semiconductor devices, a cleaning device that cleans the front and back surfaces of a wafer with a brush is widely used (see, for example, Patent Document 1).

[0003] The cleaning device shown in Patent Document 1 removes foreign substances attached to the wafer by sliding the cleaning brush on the front and back surfaces of the wafer while the cleaning brush is in contact with the wafer.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the cleaning device shown in Patent Document 1 cannot normally remove foreign substances when the cleaning brush is not in contact with the wafer, which poses a problem.

[0006] An object of the present invention is to provide a cleaning device and a cleaning method capable of grasping whether the cleaning brush is in contact with the wafer.

Means for Solving the Problems

[0007] To solve the above-mentioned problems and achieve the objective, the present invention provides a cleaning apparatus for a wafer, comprising: a plurality of support parts that support the outer edge of the wafer; a first cleaning tool fixed to a first arm for cleaning the surface side of the wafer supported by the plurality of support parts; a second cleaning tool fixed to a second arm for cleaning the back side of the wafer supported by the plurality of support parts; a first moving unit that moves the first cleaning tool to a contact position and a retracted position in which the first cleaning tool contacts the surface side of the wafer; a second moving unit that moves the second cleaning tool to a contact position and a retracted position in which the second cleaning tool contacts the back side of the wafer; a cleaning liquid supply unit that supplies cleaning liquid to the surface side and the back side of the wafer, respectively; a first displacement meter that detects the displacement of the first cleaning tool relative to the first arm; and a second displacement meter that detects the displacement of the second cleaning tool relative to the second arm.

[0008] Furthermore, the above-described cleaning device may also detect abnormalities in the first cleaning tool based on the displacement of the first cleaning tool measured by the first displacement sensor, and detect abnormalities in the second cleaning tool based on the displacement of the second cleaning tool measured by the second displacement sensor.

[0009] Furthermore, in the above-described cleaning device, contact of the first cleaning tool with the surface may be detected based on the displacement of the first cleaning tool detected by the first displacement sensor, and contact of the second cleaning tool with the back surface may be detected based on the displacement of the second cleaning tool detected by the second displacement sensor.

[0010] Furthermore, the above-described cleaning apparatus may also include an alarm unit that issues an alarm if contact between at least one of the first cleaning tool and the second cleaning tool is not detected during the cleaning of the wafer.

[0011] The present invention relates to a method for cleaning a wafer using a cleaning apparatus, comprising: a support step of supporting the outer edge of the wafer with a plurality of support parts; a cleaning step of cleaning the surface side of the wafer supported by the plurality of support parts with a first cleaning tool and cleaning the back side of the wafer with a second cleaning tool; and a displacement detection step of detecting the displacement of the first cleaning tool relative to the first arm and detecting the displacement of the second cleaning tool relative to the second arm.

[0012] Furthermore, the above cleaning method may further include a determination step that determines whether the first cleaning tool and the second cleaning tool are normal or abnormal based on the displacement of the first cleaning tool and the displacement of the second cleaning tool detected in the displacement detection step.

[0013] Furthermore, the above cleaning method may also include an alarm step in which the displacement detection step and the determination step are performed simultaneously with the cleaning step, and the determination step detects contact of the first cleaning tool with the surface side based on the displacement of the first cleaning tool and detects contact of the second cleaning tool with the back side based on the displacement of the second cleaning tool, and issues an alarm if contact of at least one of the first cleaning tool and the second cleaning tool is not detected during the execution of the cleaning step. [Effects of the Invention]

[0014] The present invention has the effect of being able to determine whether or not the cleaning brush is in contact with the wafer. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 is a schematic perspective view showing an example of the configuration of a cleaning device according to Embodiment 1. [Figure 2] Figure 2 is a cross-sectional view showing the main parts of the cleaning device shown in Figure 1. [Figure 3] Figure 3 is a schematic perspective view showing the wafer to be cleaned by the cleaning apparatus shown in Figure 1. [Figure 4]FIG. 4 is a flowchart showing the flow of the cleaning method according to Embodiment 1. [Figure 5] FIG. 5 is a side view schematically showing a state in which a wafer is supported by a support roller and the wafer is rotating in the support step of the cleaning method shown in FIG. 4. [Figure 6] FIG. 6 is a side view schematically showing a state in which a cleaning brush is rotating and a cleaning liquid is supplied to a wafer in the support step of the cleaning method shown in FIG. 4. [Figure 7] FIG. 7 is a side view schematically showing a state in which a cleaning brush is positioned on the centers of the front and back surfaces of a wafer in the cleaning preparation step of the cleaning method shown in FIG. 4. [Figure 8] FIG. 8 is a side view schematically showing a state in which a wafer is sandwiched by a cleaning brush in the cleaning step of the cleaning method shown in FIG. 4. [Figure 9] FIG. 9 is a side view schematically showing a state in which a cleaning brush is moved to the outer peripheral side of a wafer in the cleaning step of the cleaning method shown in FIG. 4. [Figure 10] FIG. 10 is a side view schematically showing a state in which a cleaning brush is positioned on the outer periphery of a wafer in the cleaning step of the cleaning method shown in FIG. 4. [Figure 11] FIG. 11 is a side view schematically showing the post-cleaning step of the cleaning method shown in FIG. 4.

Embodiments for Carrying Out the Invention

[0016] Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. Further, the constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Also, various omissions, substitutions, or changes in the configuration can be made without departing from the gist of the present invention.

[0017] 〔Embodiment 1〕 A cleaning apparatus according to Embodiment 1 of the present invention will be described based on the drawings. FIG. 1 is a perspective view schematically showing a configuration example of the cleaning apparatus according to Embodiment 1. FIG. 2 is a cross-sectional view showing a main part of the cleaning apparatus shown in FIG. 1. FIG. 3 is a perspective view schematically showing a wafer 200 to be cleaned by the cleaning apparatus shown in FIG. 1.

[0018] (Wafer) The cleaning apparatus 1 shown in FIGS. 1 and 2 according to Embodiment 1 is a cleaning apparatus for cleaning the wafer 200 shown in FIG. 3. In Embodiment 1, the wafer 200 to be cleaned by the cleaning apparatus 1 is a disk-shaped semiconductor wafer or an optical device wafer having a substrate 201 made of silicon, sapphire, gallium, or the like.

[0019] As shown in FIG. 3, a plurality of division planned lines 203 intersecting each other are set on the surface 202 of the wafer 200, and devices 204 are formed in regions partitioned by the division planned lines 203. The device 204 is, for example, an integrated circuit such as an IC (Integrated Circuit) or an LSI (Large Scale Integration), an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), an optical element such as an LED (Light-Emitting Diode), or a memory (semiconductor memory device). The wafer 200 is divided into individual devices 204 along the division planned lines 203. In the present invention, the wafer 200 may not have the devices 204 formed thereon.

[0020] In Embodiment 1, a tape 210, which is a surface protection member, is disposed on the surface 202 of the wafer 200, and the back surface 205 on the back side of the surface 202 is ground and thinned to a predetermined thickness. In the present invention, the wafer 200 may not have the tape 210 disposed on the surface 202.

[0021] (Cleaning apparatus) The cleaning apparatus 1 is a device that cleans the surface 211 of the tape 210 on the surface 202 side of the wafer 200 and the back surface 205 of the wafer 200 while rotating the wafer 200 around its axis. As shown in Figure 1, the cleaning apparatus 1 comprises a support unit 10, a cleaning fluid supply unit 40, a first cleaning unit 20, a second cleaning unit 21, a controller 100, and an alarm unit 110. The support unit 10, the cleaning fluid supply unit 40, and the cleaning units 20 and 21 of the cleaning apparatus 1 are housed in a cleaning chamber (not shown).

[0022] The support unit 10 supports the wafer 200 at at least three points on its outer edge and rotates the wafer 200 around its axis. The support unit 10 comprises a first movable support 11 and a second movable support 12. The first movable support 11 has a built-in motor (not shown) and a pair of support rollers 13 (corresponding to support parts) on its upper surface that rotate around the axis by the driving force of the motor. The support rollers 13 comprise a large-diameter portion 131 and a small-diameter portion 132 provided coaxially with the large-diameter portion 131. Both the large-diameter portion 131 and the small-diameter portion 132 are formed in the shape of a thick disc. Furthermore, the outer edge of the small-diameter portion 132 is formed in an inverse taper shape so that it gradually becomes smaller in diameter as it approaches the large-diameter portion 131.

[0023] The second movable support 12 has a motor (not shown) built in, and a single support roller 14 (corresponding to a support part) is provided on its upper surface that rotates around its axis by the driving force of the motor. The configuration of the support roller 14 is the same as that of the support roller 13, so the same parts are given the same reference numerals and their explanation is omitted.

[0024] Furthermore, the second movable support 12 is moved by an air cylinder (not shown) in a direction toward or toward the first movable support 11. When the second movable support 12 approaches the first movable support 11, the support unit 10 holds the outer edge of the wafer 200 with the support rollers 13 and 14 placing the wafer 200 on the large diameter portion 131 and the outer edge of the small diameter portion 132 in contact with the outer edge of the wafer 200. When the support unit 10 holds the wafer 200, the support rollers 13 and 14 are arranged at equal intervals (120 degrees apart) in the circumferential direction with respect to the wafer 200. The support unit 10 rotates the wafer 200 around its axis by rotating the support rollers 13 and 14 around their axis using a motor. In this way, the support unit 10 is equipped with a plurality of support rollers 13 and 14 that support the outer edge of the wafer 200.

[0025] The cleaning solution supply unit 40 supplies cleaning solution 41 (pure water in Embodiment 1) to the front surface 211 and back surface 205 of the tape 210 on the front surface 202 side of the wafer 200, respectively. The cleaning solution supply unit 40 includes a first cleaning solution supply nozzle 42 and a second cleaning solution supply nozzle 43.

[0026] The first cleaning fluid supply nozzle 42 supplies cleaning fluid 41 to the surface 211 of the tape 210 on the surface 202 side of the wafer 200 supported by the support unit 10. The first cleaning fluid supply nozzle 42 has a nozzle 421 that faces the surface 211 of the tape 210 on the surface 202 side of the wafer 200 supported by the support unit 10 and sprays the cleaning fluid 41.

[0027] The second cleaning fluid supply nozzle 43 supplies cleaning fluid 41 to the back surface 205 side of the wafer 200 supported by the support unit 10. The second cleaning fluid supply nozzle 43 is facing the back surface 205 of the wafer 200 supported by the support unit 10 and has a nozzle 431 for spraying cleaning fluid 41. The cleaning fluid supply nozzles 42 and 43 supply cleaning fluid 41 from a supply source (not shown) to the wafer 200 supported by the support unit 10 from their tip nozzles 421 and 431.

[0028] The first cleaning unit 20 and the second cleaning unit 21 contact the surface 211 and back surface 205 sides of the tape 210 on the surface 202 side of the wafer 200 supported by the support unit 10, respectively, to clean the surface 211 and back surface 205 sides of the tape 210 on the surface 202 side. As shown in Figure 2 and other figures, the cleaning units 20 and 21 each include a cleaning brush 22, a rotating support unit 23, a support arm 24, a moving unit 25, and a displacement meter 26.

[0029] The cleaning brush 22 has a circular cleaning surface 221, and the cleaning surface 221 contacts the surface 211 of the tape 210 on the surface 202 side of the wafer 200 or the back surface 205 of the wafer 200 to clean the surface 211 or back surface 205 of the tape 210 on the surface 202 side of the wafer 200. The cleaning brush 22 is a sponge made of a synthetic resin such as PVA (Polyvinyl Alcohol) and is formed in the shape of a disc.

[0030] The cleaning brush 22 of the first cleaning unit 20 (hereinafter referred to as reference numeral 22-1) is a first cleaning tool that cleans the surface 211 of the tape 210 on the surface 202 side of the wafer 200 supported by a plurality of support rollers 13, 14. The cleaning brush 22 of the second cleaning unit 21 (hereinafter referred to as reference numeral 22-2) is a second cleaning tool that cleans the back surface 205 side of the wafer 200 supported by a plurality of support rollers 13, 14.

[0031] The rotating support unit 23 supports the cleaning brushes 22-1 and 22-2 so that they can rotate around an axis perpendicular to the surface 211 and back surface 205 sides of the tape 210 on the surface 202 side of the wafer 200 held by the support unit 10. As shown in Figure 2, the rotating support unit 23 includes a disc-shaped support member 231 that supports the cleaning brushes 22-1 and 22-2, and a motor 232 that rotates the cleaning brushes 22-1 and 22-2 around an axis. The motor 232 is fixed to a support arm 24 or the like. The output shaft of the motor 232 is attached to the support member 231 via a ball spline 233. The output shaft of the motor 232 is attached to a spline nut 234 of the ball spline 233, and a spline shaft 235 that is movable in the axial direction relative to the spline nut 234 is attached to the support member 231.

[0032] Furthermore, a spring 236 is provided between the spline nut 234 of the ball spline 233 and the support member 231, which presses the support member 231, i.e., the cleaning brushes 22-1 and 22-2, toward the surface 211 or back surface 205 side of the tape 210 on the surface 202 side of the wafer 200. The spring 236 of the first cleaning unit 20 (hereinafter referred to as reference numeral 236-1) is a first elastic member that presses the cleaning brush 22-1 toward the surface 211 of the tape 210 on the surface 202 side of the wafer 200, which is supported by the support rollers 13 and 14. The spring 236 of the second cleaning unit 21 (hereinafter referred to as reference numeral 236-2) is a second elastic member that presses the cleaning brush 22-2 toward the back surface 205 side of the wafer 200, which is supported by the support rollers 13 and 14.

[0033] The rotation support section 23 rotates as the motor 232 rotates its output shaft around its axis, causing the spline nut 234 and spline shaft 235 to rotate together, and the cleaning brushes 22-1 and 22-2 rotate around their axis while being pressed against the surface 211 and back 205 sides of the tape 210 on the surface 202 side of the wafer 200. The rotation support section 23 of the cleaning units 20 and 21 rotates the cleaning brushes 22-1 and 22-2 in the same direction around their axes.

[0034] Furthermore, the rotating support section 23 has a spline shaft 235 that is movable in the axial direction relative to the spline nut 234 of the ball spline 233, and the spring 236 biases the cleaning brushes 22-1 and 22-2 toward the wafer 200, so when the cleaning brushes 22-1 and 22-2 come into contact with the wafer 200, the cleaning brushes 22-1 and 22-2 and the support member 231 are displaced from the position shown by the solid line in Figure 2 before contact to the position shown by the dashed line in Figure 2. In this way, the cleaning brushes 22-1 and 22-2 are attached to the support arm 24 by the rotating support section 23 so that they can move toward and away from the support arm 24.

[0035] The support arm 24 supports the rotating support unit 23. The support arm 24 is a case that extends linearly parallel to the surface 211 and back surface 205 sides of the tape 210 on the surface 202 side of the wafer 200 held by the support unit 10, with a space provided inside. The support arm 24 swings around one end 241 located on the outer circumference of the wafer 200 held by the support unit 10. The support arm 24 has a motor 232 fixed inside the other end 242, and the cleaning brushes 22-1 and 22-2 are exposed from the other end 242 to hold the rotating support unit 23.

[0036] Furthermore, the support arm 24 secures the main body of the motor 232 within the other end 242 via a fixing case 237. In Embodiment 1, the support arms 24 of the cleaning units 20 and 21 are formed to be of equal length and are positioned so that one end 241 and the other end 242 overlap.

[0037] In this embodiment, the support arm 24 of the first cleaning unit 20 (hereinafter referred to as reference numeral 24-1) is the first arm, and the support arm 24 of the second cleaning unit 21 (hereinafter referred to as reference numeral 24-2) is the second arm. Thus, in embodiment 1, the cleaning brush 22-1 of the first cleaning unit 20 is rotatably attached (fixed) to the support arm 24-1 around its axis via a spring 236-1. In embodiment 1, the cleaning brush 22-2 of the second cleaning unit 21 is rotatably attached (fixed) to the support arm 24-2 around its axis via a spring 236-2.

[0038] The moving unit 25 swings the support arms 24-1 and 24-2 around one end 241, and moves the support arms 24-1 and 24-2 in a direction that brings the other ends 242 closer together or further apart. The moving unit 25 swings the support arms 24-1 and 24-2 so that the other ends 242 pass over the center of the wafer 200 supported by the support rollers 13 and 14 of the support unit 10.

[0039] The moving unit 25 brings the other ends 242 of the support arms 24-1 and 24-2, i.e., the cleaning brushes 22-1 and 22-2, closer together while they are positioned on the surface 211 or back surface 205 of the tape 210 on the surface 202 side of the wafer 200 supported by the support rollers 13 and 14, thereby positioning the cleaning brushes 22-1 and 22-2 in contact with the surface 211 or back surface 205 of the tape 210 on the surface 202 side of the wafer 200. Furthermore, the moving unit 25 separates the other ends 242 of the support arms 24-1, 24-2, i.e., the cleaning brushes 22-1, 22-2, while they are positioned on the surface 211 or back surface 205 of the tape 210 on the surface 202 side of the wafer 200 supported by the support rollers 13, 14. This positions the cleaning brushes 22-1, 22-2 in a retracted position, away from the surface 211 or back surface 205 of the tape 210 on the surface 202 side of the wafer 200.

[0040] In this way, the moving unit 25 moves the cleaning brushes 22-1 and 22-2 to a contact position and a retracted position where the cleaning brushes 22-1 and 22-2 contact the surface 211 or back surface 205 of the tape 210 on the surface 202 side of the wafer 200 supported by the support rollers 13 and 14. In the retracted position, the cleaning brushes 22-1 and 22-1 are positioned relative to the support arms 24-1 and 24-2 as shown by the solid lines in Figure 2. In the contact position, the cleaning brushes 22-1 and 22-1 are positioned relative to the support arms 24-1 and 24-2 as shown by the dashed lines in Figure 2.

[0041] In this way, by moving between the retracted position and the contact position, the cleaning brushes 22-1 and 22-2 move relative to the support arms 24-1 and 24-2 between the positions shown by the solid line and the positions shown by the dashed line in Figure 2. Furthermore, as the amount of wear on the cleaning brushes 22-1 and 22-2 increases, the displacement of the cleaning brushes 22-1 and 22-2 relative to the support arms 24-1 and 24-2 when moving between the retracted position and the contact position decreases. For example, the aforementioned displacement when the cleaning brushes 22-1 and 22-2 are not worn at all is 3 mm.

[0042] The movement unit 25 (hereinafter referred to as reference numeral 25-1) of the first cleaning unit 20 is a first movement unit that moves the cleaning brush 22-1 between a contact position where the cleaning brush 22-1 contacts the surface 211 of the tape 210 on the surface 202 side of the wafer 200 and a retracted position. The movement unit 25 (hereinafter referred to as reference numeral 25-2) of the second cleaning unit 21 is a second movement unit that moves the cleaning brush 22-2 between a contact position where the cleaning brush 22-2 contacts the back surface 205 side of the wafer 200 and a retracted position.

[0043] In Embodiment 1, the moving units 25-1 and 25-2 are equipped with a motor or ball screw that pivots the support arms 24-1 and 24-2 around one end 241. In Embodiment 1, the moving units 25-1 and 25-2 are equipped with a cylinder or the like that moves the support arms 24-1 and 24-2 in a direction that brings the other ends 242 closer together or further apart. In Embodiment 1, the moving units 25-1 and 25-2 bring the other ends 242 of the support arms 24-1 and 24-2 closer together to a position where, at the contact position, the cleaning brushes 22-1 and 22-2 are a certain amount closer to each other than the position where the cleaning brushes 22-1 and 22-2 contact the surface 211 and back surface 205 of the tape 210 on the surface 202 side of the wafer 200 supported by the support rollers 13 and 14.

[0044] The displacement sensor 26 detects the displacement of the cleaning brushes 22-1 and 22-2 relative to the support arms 24-1 and 24-2 (the change in distance from the displacement sensor 26 to the support member 231). In Embodiment 1, the displacement sensor 26 is housed within the other end 242 of the support arms 24-1 and 24-2. The displacement sensor 26 detects the change in distance to the support member 231 and thereby detects the displacement of the support member 231, i.e., the cleaning brushes 22-1 and 22-2.

[0045] In Embodiment 1, the displacement meter 26 detects the change in distance from the cleaning brushes 22-1 and 22-2 when they are in the retracted position to the support member 231 when they are in the contact position, and outputs the detection result to the controller 100. In Embodiment 1, the displacement meter 26 detects the contact of the cleaning brushes 22-1 and 22-2 with the surface 211 or back surface 205 side of the tape 210 on the surface 202 side of the wafer 200 by detecting the change in distance from the cleaning brushes 22-1 and 22-2 when they are in the retracted position to the support member 231 when they are in the contact position.

[0046] The displacement meter 26 (hereinafter referred to as reference numeral 26-1) of the first cleaning unit 20 is a first displacement meter that detects the displacement of the support member 231, i.e., the cleaning brush 22-1, relative to the support arm 24-1, and is also a first detection unit that detects contact between the surface 202 side of the cleaning brush 22-1 and the surface 211 of the tape 210. The displacement meter 26 (hereinafter referred to as reference numeral 26-2) of the second cleaning unit 21 is a second displacement meter that detects the displacement of the support member 231, i.e., the cleaning brush 22-2, relative to the support arm 24-2, and is also a second detection unit that detects contact between the back surface 205 side of the cleaning brush 22-2.

[0047] The controller 100 controls each of the above-described components of the cleaning apparatus 1 to cause the cleaning apparatus 1 to perform the cleaning operation of the wafer 200. The controller 100 is a computer having an arithmetic processing unit with a microprocessor such as a CPU (central processing unit), a storage device with memory such as ROM (read-only memory) or RAM (random access memory), and an input / output interface device. The arithmetic processing unit of the controller 100 performs arithmetic processing according to the computer program stored in the storage device and outputs control signals for controlling the cleaning apparatus 1 to each of the above-described units of the cleaning apparatus 1 via the input / output interface device.

[0048] The alarm unit 110 issues an alarm to the operator of the cleaning device 1. In Embodiment 1, the alarm unit 110 is a warning light connected to the controller 100 that emits sound and light to alert the operator.

[0049] Furthermore, in Embodiment 1, the controller 100 is connected to a display unit and an input unit. The display unit has a display screen that displays various information. The input unit is used when an operator inputs information to the controller 100 of the cleaning device 1. The input unit has a touch panel superimposed on the display screen of the display unit.

[0050] (Cleaning method) Next, a cleaning method according to Embodiment 1 will be described. Figure 4 is a flowchart showing the flow of the cleaning method according to Embodiment 1. The cleaning method according to Embodiment 1 is a method of cleaning a wafer 200 with a cleaning apparatus 1 having the configuration described above. As shown in Figure 4, the cleaning method according to Embodiment 1 comprises a support step 1001, a cleaning preparation step 1002, a cleaning step 1003, a displacement detection step 1004, a determination step 1005, an alarm step 1006, and a post-cleaning step 1007.

[0051] (Support step) Figure 5 is a schematic side view showing the state in which the wafer is supported by the support roller and rotated during the support step of the cleaning method shown in Figure 4. Figure 6 is a schematic side view showing the state in which the cleaning brush is rotated and cleaning fluid is supplied to the wafer during the support step of the cleaning method shown in Figure 4.

[0052] Support step 1001 is a step in which the outer edge of the wafer 200 is supported by a plurality of support rollers 13, 14. In Embodiment 1, in support step 1001, the cleaning device 1 first receives cleaning conditions from an operator or the like by operating an input unit, and the controller 100 receives and registers the cleaning conditions. When the controller 100 receives a cleaning start instruction, the cleaning device 1 performs support step 1001. When the cleaning start instruction is received, the cleaning device 1 positions the cleaning brushes 22-1 and 22-2 in a retracted position and also retracts the cleaning brushes 22-1 and 22-2 from above and below the support unit 10.

[0053] In Embodiment 1, during the support step 1001, the cleaning apparatus 1, with the controller 100 separated from the second movable support 12 and the first movable support 11 of the support unit 10, carries the wafer 200 to a predetermined position between the support rollers 13 and 14 by a transport means (not shown). In Embodiment 1, during the support step 1001, the cleaning apparatus 1, with the controller 100 bringing the second movable support 12 closer to the first movable support 11, supports the outer edge of the wafer 200 with the support rollers 13 and 14.

[0054] In Embodiment 1, during the support step 1001, as shown in Figure 5, the controller 100 drives a motor to rotate the support rollers 13 and 14 around their axes, thereby rotating the wafer 200 around its axis. In Embodiment 1, during the support step 1001, as shown in Figure 6, the controller 100 causes the cleaning device 1 to supply cleaning liquid 41 from the nozzles 421 and 431 of the cleaning liquid supply nozzles 42 and 43 of the cleaning liquid supply unit 40 to the front surface 211 and back surface 205 sides of the tape 210 on the front surface 202 side of the wafer 200, respectively. In Embodiment 1, during the support step 1001, as shown in Figure 6, the controller 100 drives a motor 232 to rotate the cleaning brushes 22-1 and 22-2 of the cleaning units 20 and 21 around their axes in the same direction.

[0055] In Embodiment 1, during the support step 1001, the controller 100 of the cleaning device 1 rotates the cleaning brushes 22-1 and 22-2 at 500 rpm and the wafer 200 at 40 rpm.

[0056] (Preparation step for washing) Figure 7 is a schematic side view showing the cleaning brush positioned on the center of the front and back surfaces of the wafer during the cleaning preparation step of the cleaning method shown in Figure 4. The cleaning preparation step 1002 is a step to prepare the wafer 200 for cleaning with cleaning brushes 22-1 and 22-2.

[0057] In Embodiment 1, the cleaning preparation step 1002 involves the cleaning apparatus 1, in which the controller 100 controls the moving units 25-1 and 25-2 to swing the support arms 24-1 and 24-2 around one end 241, so that the cleaning brushes 22-1 and 22-2 are positioned on the center of the front surface 211 and back surface 205 of the tape 210 on the front surface 202 side of the wafer 200, as shown in Figure 7.

[0058] (Washing step) Figure 8 is a schematic side view showing the state in which the wafer is held between the cleaning brushes during the cleaning step of the cleaning method shown in Figure 4. Figure 9 is a schematic side view showing the state in which the cleaning brushes are moved towards the outer periphery of the wafer during the cleaning step of the cleaning method shown in Figure 4. Figure 10 is a schematic side view showing the state in which the cleaning brushes are positioned on the outer periphery of the wafer during the cleaning step of the cleaning method shown in Figure 4.

[0059] The cleaning step 1003 is a step in which the surface surface 211 of the tape 210 on the surface 202 side of the wafer 200 supported by a plurality of support rollers 13, 14 is cleaned with a cleaning brush 22-1, and the back surface 205 side of the wafer 200 is cleaned with a cleaning brush 22-2. In Embodiment 1, in the cleaning step 1003, the cleaning apparatus 1 controls the moving units 25-1, 25-2 with the controller 100 to bring the other ends 242 of the support arms 24-1, 24-2 closer together so that the cleaning brushes 22-1, 22-2 are in contact with each other, and as shown in Figure 8, the cleaning brushes 22-1, 22-2 grip the wafer 200 supported by the support rollers 13, 14. In Embodiment 1, during the cleaning step 1003, the cleaning apparatus 1 controls the moving units 25-1 and 25-2 with the controller 100 to position the cleaning brushes 22-1 and 22-2 in contact with each other, and then swings the support arms 24-1 and 24-2 to move the cleaning brushes 22-1 and 22-2 toward the outer circumference along the radial direction of the wafer 200, as shown in Figure 9.

[0060] In Embodiment 1, during cleaning step 1003, the cleaning apparatus 1, with the controller 100 controlling the moving units 25-1 and 25-2 to position the cleaning brushes 22-1 and 22-2 in contact with each other, positions the cleaning brushes 22-1 and 22-2 on the outer periphery of the wafer 200, as shown in Figure 10. Thus, in Embodiment 1, during cleaning step 1003, the cleaning apparatus 1 rotates the wafer 200 around its axis and moves the cleaning brushes 22-1 and 22-2, which are in contact with the surface 211 and back 205 sides of the tape 210 on the surface 202 side, outward along the radial direction of the wafer 200, thereby cleaning the surface 211 and back 205 sides of the tape 210 on the surface 202 side of the wafer 200 with the cleaning brushes 22-1 and 22-2.

[0061] (Displacement detection step) Displacement detection step 1004 is a step that detects the displacement of the cleaning brush 22-1 relative to the support arm 24-1, and also detects the displacement of the cleaning brush 22-2 relative to the support arm 24-2. Note that displacement detection step 1004 and judgment step 1005 are performed simultaneously with cleaning step 1003.

[0062] In Embodiment 1, in displacement detection step 1004, the cleaning device 1 detects the displacement of the cleaning brushes 22-1 and 22-2 when they are positioned from the retracted position to the contact position in cleaning step 1003, based on the detection results of the displacement meters 26-1 and 26-2 detected by the controller 100.

[0063] (Decision-making step) The determination step 1005 is a step in which the cleaning brush 22-1 is detected to be in contact with the surface 211 of the tape 210 on the surface 202 side of the wafer 200 based on the displacement of the cleaning brush 22-1, and the cleaning brush 22-2 is detected to be in contact with the back surface 205 side of the wafer 200 based on the displacement of the cleaning brush 22-2. In Embodiment 1, in the determination step 1005, the controller 100 determines whether the cleaning brushes 22-1 and 22-2 are in contact with the wafer 200 based on the detection results of the displacement meters 26-1 and 26-2, and based on the displacement of the cleaning brushes 22-1 and 22-2 when they were positioned from the retracted position to the contact position in the cleaning step 1003.

[0064] In Embodiment 1, in the determination step 1005, if there is no displacement of the cleaning brushes 22-1 and 22-2 when the controller 100 is positioned from the retracted position to the contact position (i.e., zero displacement), it is detected that the cleaning brushes 22-1 and 22-2 are not in contact with the wafer 200, i.e., an abnormality of the cleaning brushes 22-1 and 22-2, and the process proceeds to the alarm step 1006. In the present invention, in the determination step 1005, if there is displacement of the cleaning brushes 22-1 and 22-2 positioned at the contact position, it is determined that the cleaning brushes 22-1 and 22-2 are in contact with the wafer 200, i.e., the cleaning brushes 22-1 and 22-2 are normal.

[0065] Furthermore, in Embodiment 1, in the determination step 1005, if the controller 100 determines that both cleaning brushes 22-1 and 22-2 are in contact with the wafer 200, it determines whether the displacement of the cleaning brushes 22-1 and 22-2 when they are positioned from the retracted position to the contact position detected in the displacement detection step 1004 is less than a threshold.

[0066] In Embodiment 1, in the determination step 1005, if the controller 100 determines that the displacement of at least one of the cleaning brushes 22-1 and 22-2 is less than a threshold, it detects that at least one of the cleaning brushes 22-1 and 22-2 is in a worn state and detects that at least one of the cleaning brushes 22-1 and 22-2 is in an abnormal state. In Embodiment 1, in the determination step 1005, if the controller 100 determines that the displacement of both cleaning brushes 22-1 and 22-2 is greater than or equal to a threshold, it detects that the cleaning brushes 22-1 and 22-2 are not worn and detects that the cleaning brushes 22-1 and 22-2 are normal.

[0067] For example, in Embodiment 1, the displacement when unworn cleaning brushes 22-1 and 22-2 come into contact with the wafer 200 is, for example, 3 mm. When cleaning brushes 22-1 and 22-2 wear down, the displacement decreases, and in Embodiment 1, for example, when the displacement falls below, for example, 2 mm (corresponding to a threshold), it is detected that the brushes are worn and in an abnormal state. Thus, in Embodiment 1, in the determination step, the cleaning device 1 detects an abnormality in cleaning brush 22-1 based on the displacement of cleaning brush 22-1 measured by displacement meter 26-1, and detects an abnormality in cleaning brush 22-2 based on the displacement of cleaning brush 22-2 measured by displacement meter 26-2. Thus, in Embodiment 1, the determination step is a step in determining whether cleaning brushes 22-1 and 22-2 are normal (no replacement needed) or abnormal (replacement needed) based on the displacement of cleaning brush 22-1 and cleaning brush 22-2 detected in the displacement detection step 1004.

[0068] (Alarm step) Alarm step 1006 is a step in which an alarm is issued if contact between at least one of the cleaning brushes 22-1 and 22-2 is not detected during the execution of cleaning step 1003. In Embodiment 1, in alarm step 1006, the controller 100 operates the alarm unit 110, which emits sound and light to alert the operator. Thus, in alarm step 1006, the alarm unit 110 issues an alarm if contact between at least one of the cleaning brushes 22-1 and 22-2 is not detected during cleaning of the wafer 200.

[0069] If an alarm is issued in alarm step 1006, the operator operates the input unit or the like to clean the wafer 200 again after cleaning in cleaning step 1003, i.e., repeat cleaning step 1003. If contact is detected by both displacement meter 26-1 and displacement meter 26-2 after alarm step 1006 or during cleaning step 1003, and after cleaning step 1003, the process proceeds to post-cleaning step 1007.

[0070] (Post-cleaning step) Figure 11 is a schematic side view showing the post-cleaning step of the cleaning method shown in Figure 4. Post-cleaning step 1007 is a step performed after cleaning the wafer 200. In Embodiment 1, in post-cleaning step 1007, the cleaning apparatus 1, with the controller 100 controlling the moving units 25-1 and 25-2, separates the other ends 242 of the support arms 24-1 and 24-2 from each other, as shown in Figure 11, positions the cleaning brushes 22-1 and 22-2 in a retracted position, and separates the cleaning brushes 22-1 and 22-2 from each other.

[0071] After the post-cleaning step 1007, the cleaning device 1 determines whether the controller 100 has performed the cleaning step 1003 the number of times specified by the cleaning conditions (for example, 3 times in Embodiment 1) (step 1008). If the cleaning device 1 determines that the controller 100 has not performed the cleaning step 1003 the number of times specified by the cleaning conditions (step 1008: No), it returns to the cleaning preparation step 1002. If the cleaning device 1 determines that the controller 100 has performed the cleaning step 1003 the number of times specified by the cleaning conditions (step 1008: Yes), The cleaning method is terminated by stopping the rotation of the wafer 200, the supply of the cleaning solution 41, and the rotation of the cleaning brushes 22-1 and 22-2. The wafer 200 is then transported to the next process and cleaned with a chemical solution (e.g., ozone, hydrofluoric acid, or ammonia) on a spinner table.

[0072] Furthermore, in Embodiment 1, after the controller 100 determines that the cleaning step 1003 has been performed the number of times specified by the cleaning conditions (step 1008: Yes), if the determination step 1005 determines that at least one of the cleaning brushes 22-1 and 22-2 is worn out and in an abnormal state, the alarm unit 110 issues an alarm to the operator indicating that the cleaning brushes 22-1 and 22-2 need to be replaced.

[0073] As described above, the cleaning apparatus 1 and cleaning method according to the embodiment are equipped with displacement gauges 26-1 and 26-2 that detect the displacement of the cleaning brushes 22-1 and 22-2 relative to the support arms 24-1 and 24-2. Therefore, it is possible to detect whether the cleaning brushes 22-1 and 22-2 have come into contact with the wafer 200 based on the displacement detected by the displacement gauges 26-1 and 26-2. As a result, the cleaning apparatus 1 and cleaning method according to the embodiment have the effect of being able to determine whether or not the cleaning brushes 22-1 and 22-2 are in contact with the wafer 200 during cleaning.

[0074] It should be noted that the present invention is not limited to the embodiments and modifications described above. That is, it can be implemented with various modifications without departing from the core principles of the present invention. In the above-described Embodiment 1, the contact of the cleaning brushes 22-1 and 22-2 with the wafer 200 and the need to replace the cleaning brushes 22-1 and 22-2 were detected. However, in the present invention, the cleaning device 1 may only detect the need to replace the cleaning brushes 22-1 and 22-2. [Explanation of Symbols]

[0075] 1. Washing device 13,14 Support roller (support part) 22-1 Cleaning brush (first cleaning tool) 22-2 Cleaning brush (second cleaning tool) 24-1 Support arm (first arm) 24-2 Support arm (second arm) 25-1 Mobile Unit (First Mobile Unit) 25-2 Mobile Unit (Second Mobile Unit) 26-1 Displacement gauge (First displacement gauge) 26-2 Displacement gauge (second displacement gauge) 40 Cleaning fluid supply unit 41 Cleaning solution 200 wafers 202 Surface 205 Back side 236-1 Spring (First Elastic Member) 236-2 Spring (Second Elastic Member) 1001 Support step 1003 Washing Step 1004 Displacement detection step 1005 Decision Step 1006 Alarm Step

Claims

1. A wafer cleaning apparatus, Multiple support parts that support the outer edge of the wafer, A first cleaning tool fixed to a first arm and used to clean the surface side of the wafer supported by the plurality of support parts, A second cleaning tool fixed to a second arm and used to clean the back side of the wafer supported by the plurality of support parts, A first moving unit moves the first cleaning tool between a contact position where the first cleaning tool contacts the surface side of the wafer and a retracted position, A second moving unit moves the second cleaning tool between a contact position where the second cleaning tool contacts the back surface of the wafer and a retracted position, A cleaning solution supply unit that supplies cleaning solution to the front and back sides of the wafer, respectively, A first displacement sensor for detecting the displacement of the first cleaning tool relative to the first arm, A cleaning device comprising: a second displacement meter for detecting the displacement of the second cleaning tool relative to the second arm.

2. The cleaning apparatus according to claim 1, wherein an abnormality of the first cleaning tool is detected based on the displacement of the first cleaning tool measured by the first displacement meter, and an abnormality of the second cleaning tool is detected based on the displacement of the second cleaning tool measured by the second displacement meter.

3. Based on the displacement of the first cleaning tool detected by the first displacement meter, the contact of the first cleaning tool with the surface is detected, The cleaning apparatus according to claim 2, wherein the contact of the second cleaning tool with the back surface is detected based on the displacement of the second cleaning tool detected by the second displacement meter.

4. The cleaning apparatus according to claim 3, further comprising an alarm unit that issues an alarm if contact between at least one of the first cleaning tool and the second cleaning tool is not detected during cleaning of the wafer.

5. A method for cleaning a wafer using the cleaning apparatus described in claim 1, A support step in which the outer edge of the wafer is supported by a plurality of support parts, A cleaning step in which the surface side of the wafer supported by the plurality of support parts is cleaned with a first cleaning tool and the back side of the wafer is cleaned with a second cleaning tool, A cleaning method comprising a displacement detection step of detecting the displacement of the first cleaning tool relative to the first arm and the displacement of the second cleaning tool relative to the second arm.

6. The cleaning method according to claim 5, further comprising: a determination step of determining whether the first cleaning tool and the second cleaning tool are normal or abnormal based on the displacement of the first cleaning tool and the displacement of the second cleaning tool detected in the displacement detection step.

7. The displacement detection step and the determination step are performed simultaneously with the cleaning step. In this determination step, the contact of the first cleaning tool with the surface side is detected based on the displacement of the first cleaning tool, and the contact of the second cleaning tool with the back side is detected based on the displacement of the second cleaning tool. The cleaning method according to claim 6, further comprising an alarm step of issuing an alarm if contact between at least one of the first cleaning tool and the second cleaning tool is not detected during the cleaning step.

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