Wafer cleaning equipment

Abstract

This invention provides a wafer cleaning apparatus that can obtain highly clean wafers using a two-fluid jet. [Solution] A wafer cleaning apparatus comprising: a plurality of rotating rollers that hold and rotate a wafer having a first surface and a second surface opposite thereto in an upright position to put it into a held-rotating state; a two-fluid jet type first nozzle that performs a first cleaning operation to clean the first surface of the wafer in the held-rotating state; a first lifting drive unit that moves the first nozzle vertically in order to perform the first cleaning operation by scanning; a two-fluid jet type second nozzle that performs a second cleaning operation to clean the second surface of the wafer in the held-rotating state; and a second lifting drive unit that moves the second nozzle vertically in order to perform the second cleaning operation by scanning.

Description

Technical Field

[0001] The present invention relates to a wafer cleaning apparatus.

Background Art

[0002] There is known a wafer cleaning apparatus that cleans the upper surface or both the upper and lower surfaces of a horizontally rotated wafer by means of a two-fluid jet nozzle that mixes a cleaning liquid with a gas and ejects it as a two-fluid jet (see, for example, Patent Documents 1 and 2). According to the two-fluid jet, particles, which are foreign substances adhering to the wafer, can be smoothly lifted and removed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the wafer is cleaned in a horizontal state as described above, there is a risk that particles, which are foreign substances blown off by the two-fluid jet, will fall onto the upper surface of the wafer due to the action of gravity and reattach. Therefore, there is room for improvement in obtaining a wafer with a high degree of cleanliness.

[0005] An object of the present invention is to provide a wafer cleaning apparatus capable of obtaining a wafer with a high degree of cleanliness using a two-fluid jet.

Means for Solving the Problems

[0006] One aspect of the present invention is as follows.

[0007] [1] Multiple rotating rollers that hold and rotate a wafer having a first surface and a second surface opposite to it in an upright position, thereby creating a holding and rotating state, A two-fluid jet type first nozzle performs a first cleaning operation to clean the first surface of the wafer in the held and rotating state, A first lifting drive unit moves the first nozzle vertically in order to perform the first cleaning operation by scanning, A two-fluid jet type second nozzle performs a second cleaning operation to clean the second surface of the wafer in the held and rotating state, A wafer cleaning apparatus having a second lifting drive unit that moves the second nozzle in the vertical direction in order to perform the second cleaning operation by scanning.

[0008] [2] The first nozzle is tilted downwards from the horizontal, The wafer cleaning apparatus according to [1], wherein the second nozzle is inclined downward from the horizontal direction.

[0009] [3] The first lifting drive unit has a first guide rail that extends in the vertical direction and guides the vertical movement of the first nozzle. The second lifting drive unit has a second guide rail that extends in the vertical direction and guides the vertical movement of the first nozzle. The straight line connecting the first guide rail and the second guide rail in the horizontal direction is perpendicular to the wafer in the holding and rotating state when viewed from above. The wafer cleaning apparatus according to [1] or [2], wherein the first horizontal distance between the first guide rail and the first surface of the wafer in the holding and rotating state is the same as the second horizontal distance between the second guide rail and the second surface of the wafer in the holding and rotating state.

[0010] [4] A wafer cleaning apparatus according to any one of [1] to [3], wherein the first nozzle and the second nozzle perform the scanning at the same height and the same inclination to each other, thereby simultaneously cleaning regions of the first and second surfaces of the wafer in the held and rotating state that are at the same height.

[0011] [5] The plurality of rotating rollers include a drive roller that applies rotational torque to the wafer, and a guide roller whose rotational axis is located above the rotational axis of the drive roller and which guides the rotation of the wafer. The wafer cleaning apparatus according to any one of [1] to [4], wherein the coefficient of friction of the drive roller is greater than the coefficient of friction of the guide roller.

[0012] [6] A wafer cleaning apparatus according to any one of [1] to [5], comprising an end brush for cleaning the outer peripheral end face of the wafer in the holding and rotating state by contact with the said outer peripheral end face.

[0013] [7] The wafer cleaning apparatus according to any one of [1] to [6], wherein the rotational axis of each of the plurality of rotating rollers is located below the rotational axis of the wafer in the held rotation state.

[0014] [8] A housing that forms a housing space for housing the plurality of rotating rollers, the first nozzle, the second nozzle, and the wafer in the held rotating state, A wafer cleaning apparatus according to any one of [1] to [7], comprising an exhaust device that exhausts air from the bottom of the aforementioned storage space. [Effects of the Invention]

[0015] According to the present invention, a wafer cleaning apparatus can be provided that can obtain wafers with high cleanliness using a two-fluid jet.

[0016] Moreover, according to the present invention, it is possible to improve the wafer yield by obtaining wafers with high cleanliness. The improvement in yield enables higher manufacturing efficiency of semiconductor products, allowing for the production of more high-quality products, contributing to the promotion of technological innovation and the sustainable development of the industry. The improvement in yield also reduces waste of materials consumed in the manufacturing process of semiconductor products, contributing to the efficient use of resources. Furthermore, the improvement in yield reduces waste of energy consumed in the manufacturing process of semiconductor products, resulting in a reduction in greenhouse gas emissions.

[0017] That is, the present invention enables, for example, to contribute to "Goal 9: Industry, Innovation, and Infrastructure Building", "Goal 12: Ensuring Sustainable Consumption and Production", and "Goal 13: Taking Action on Climate Change" in the Sustainable Development Goals (SDGs).

Brief Description of Drawings

[0018] [Figure 1] It is a partial cross-sectional side view showing the wafer cleaning apparatus according to the first embodiment of the present invention. [Figure 2] It is a partial cross-sectional side view when viewed in the direction of arrow A in FIG. 1. [Figure 3] It is a partial cross-sectional side view when viewed in the direction of arrow B in FIG. 1. [Figure 4] It is an explanatory diagram for explaining the operation of the first nozzle shown in FIG. 1. <0>< / [Figure 5] It is a partial cross-sectional side view showing the wafer cleaning apparatus according to the second embodiment of the present invention from the same perspective as FIG. 2. [Figure 6] It is a partial cross-sectional side view showing the wafer cleaning apparatus shown in FIG. 5 from the same perspective as FIG. 3.

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be illustrated and described with reference to the drawings.

[0020] As shown in Figures 1 to 4, in the first embodiment of the present invention, the wafer cleaning apparatus 1 includes a plurality of (four in this embodiment) rotating rollers 3 that hold and rotate a wafer 2 having a first surface 2a and a second surface 2b on the opposite side in an upright position (as shown in Figures 1 to 4) to bring it into a holding and rotating state; a two-fluid jet type first nozzle 4 that performs a first cleaning operation to clean the first surface 2a of the wafer 2 in the holding and rotating state; a first lifting drive unit 5 that moves the first nozzle 4 vertically in order to perform the first cleaning operation by scanning; a two-fluid jet type second nozzle 6 that performs a second cleaning operation to clean the second surface 2b of the wafer 2 in the holding and rotating state; and a second lifting drive unit 7 that moves the second nozzle 6 vertically in order to perform the second cleaning operation by scanning.

[0021] With this configuration, both sides of wafer 2 can be cleaned by the first and second cleaning operations. Furthermore, since the cleaning is performed with wafer 2 in an upright position, the particles, which are foreign matter blown away by the two-fluid jet, fall below wafer 2 due to gravity, thus suppressing the re-adhesion of particles to wafer 2. Therefore, a wafer 2 with high cleanliness can be obtained.

[0022] A more detailed description of this embodiment is given below. In this application, the up-down direction refers to the vertical direction. In this embodiment, the direction along the rotational axis O of the wafer 2 in the held rotation state is called the front-back direction, with the first surface 2a side being the front and the second surface 2b side being the rear, and the direction perpendicular to both the up-down and front-back directions being called the left-right direction (left side is the left side in Figure 3).

[0023] Wafer 2 is a semiconductor wafer such as a silicon wafer. Wafer 2 is disc-shaped with an axis that becomes the rotational axis O when it is held and rotated, and the outer surface of wafer 2 is composed of a circular first surface 2a, a circular second surface 2b, and an outer peripheral end surface 2c. In this embodiment, the rotational axis O of wafer 2 is perpendicular to the vertical direction.

[0024] The multiple rotating rollers 3 described above are arranged in a circumferential direction with respect to the rotational axis O of the wafer 2, so as to be located on both sides in the left-right direction with respect to the rotational axis O of the wafer 2, and each has a rotational axis P parallel to the rotational axis O of the wafer 2.

[0025] The rotating roller 3 has a circumferential groove 3a formed along a circle centered on its own rotational axis P. The outer edge of the wafer 2 is positioned within the circumferential groove 3a and held by contact with the surface of the circumferential groove 3a. The surface of the circumferential groove 3a contacts the outer edge 2c of the wafer 2, generating frictional force. The front edge of the circumferential groove 3a is located in front of the plane containing the first surface 2a of the wafer 2 in the held and rotating state. The rear edge of the circumferential groove 3a is located behind the plane containing the second surface 2b of the wafer 2 in the held and rotating state.

[0026] The above-described plurality of rotating rollers 3 each have a drive roller 8 whose rotational axis P is located below the rotational axis O of the wafer 2 in a held rotating state and which applies rotational torque to the wafer 2, and a guide roller 9 whose rotational axis P is located above the rotational axis P of the drive roller 8 and which guides the rotation of the wafer 2. The above-described plurality of rotating rollers 3 each have one drive roller 8 on both the left and right sides in the direction of the rotational axis O of the wafer 2. These drive rollers 8 are installed at the same height as each other. The above-described plurality of rotating rollers 3 each have one guide roller 9 on both the left and right sides in the direction of the rotational axis O of the wafer 2. These guide rollers 9 are installed at the same height as each other.

[0027] The drive roller 8 is rotated by a drive system (not shown). When the drive roller 8 rotates clockwise when viewed from the front (see the thick arrow in Figure 3), the frictional force between the surface of the circumferential groove 3a of the drive roller 8 and the outer peripheral end face 2c of the wafer 2 causes the wafer 2 to rotate counterclockwise when viewed from the front (see the white arrow in Figure 3). The guide roller 9 may be configured to rotate clockwise when viewed from the front (see the thick arrow in Figure 3) by the same drive system as the drive roller 8, or it may be configured to rotate clockwise when viewed from the front (see the thick arrow in Figure 3) by the frictional force between the surface of the circumferential groove 3a of the guide roller 9 and the outer peripheral end face 2c of the wafer 2. Note that the direction of rotation is not limited to these, and the wafer 2 and the rotating roller 3 may be configured to rotate in opposite directions.

[0028] The coefficient of friction of the drive roller 8 is greater than the coefficient of friction of the guide roller 9. With this configuration, the displacement of the wafer 2 rotated by the guide roller 9 can be suppressed, while the generation of foreign matter (dust) due to friction between the guide roller 9 and the wafer 2 can be suppressed. The guide roller 9 may be provided so that its rotational axis P is located at a height above the rotational axis O of the wafer 2, but from the viewpoint of suppressing the adhesion of dust generated by the guide roller 9 to the wafer 2, it is preferable that the guide roller 9 be provided so that its rotational axis P is located below the rotational axis O of the wafer 2 in the held rotation state, as in this embodiment. The material forming the groove surface of the drive roller 8 is not particularly limited, and is, for example, ethylene propylene diene rubber (EPDM). The material forming the groove surface of the guide roller 9 is not particularly limited, and is, for example, polyvinylidene fluoride (PVDF). These materials should preferably be selected considering factors such as the required coefficient of friction, cleanliness to prevent contamination of wafer 2, and durability to resist deformation and degradation. Furthermore, if chemicals are used as the liquids constituting the two-fluid jet, chemical resistance should also be considered.

[0029] As shown in the second embodiment of the present invention in Figures 5-6, the wafer cleaning apparatus 1 may be configured to have an end brush 10 that cleans the outer peripheral end face 2c of the wafer 2 in a held and rotating state by contact with the outer peripheral end face 2c. The end brush 10 can improve the cleanliness of the outer peripheral end face 2c of the wafer 2. Preferably, the end brush 10 is provided such that its rotational axis Q is located below the rotational axis O of the wafer 2 in a held and rotating state, and above the rotational axis P of the drive roller 8. In this embodiment, one guide roller 9 is provided to the left of the rotational axis O of the wafer 2, and one end brush 10 is provided to the right of the rotational axis O of the wafer 2. The guide roller 9 and the end brush 10 are provided at the same height.

[0030] The end face brush 10 has an outer brush surface 10a centered on the rotation axis Q. The outer edge of the wafer 2 is held by contact with the surface of the outer brush surface 10a. The front edge of the outer brush surface 10a is located in front of the plane containing the first surface 2a of the wafer 2 in the held rotation state. The rear edge of the outer brush surface 10a is located behind the plane containing the second surface 2b of the wafer 2 in the held rotation state. The end face brush 10 may be configured to be rotated clockwise when viewed from the front (see thick arrow in Figure 6) by the same drive system as the drive roller 8, or it may be configured to be rotated clockwise when viewed from the front (see thick arrow in Figure 6) by the frictional force between the outer brush surface 10a and the outer edge 2c of the wafer 2, or it may be configured to be rotated in a different rotation direction or at a different rotation speed by an independent drive system. The material forming the outer brush surface 10a of the end face brush 10 is not particularly limited and is, for example, polyvinyl alcohol (PVA).

[0031] The first nozzle 4 and the second nozzle 6 each dispense a cleaning liquid mixed with a gas as a two-fluid jet. The cleaning liquid is not particularly limited, but in this embodiment, it is de-ionized water (DIW) from the viewpoint of high cleanliness. The liquid may be carbonated water or ammonia water, or a chemical solution such as SC-1 (Standard Clean 1) or HF (hydrogen fluoride). The gas is not particularly limited, but in this embodiment, it is nitrogen (N2).

[0032] The first lifting drive unit 5 includes a first guide rail 5a that extends in the vertical direction and guides the vertical movement of the first nozzle 4, and a first drive unit (not shown) that provides the first nozzle 4 with a driving force to move along the first guide rail 5a. The first guide rail 5a is linear, extends parallel to the wafer 2 in the held rotation state, and is located on the rotational axis O of the wafer 2 in the held rotation state. The first guide rail 5a also extends perpendicular to the left-right direction and perpendicular to the front-back direction (that is, the first guide rail 5a extends linearly along the vertical direction).

[0033] The second lifting drive unit 7 includes a second guide rail 7a that extends in the vertical direction and guides the vertical movement of the second nozzle 6, and a second drive unit (not shown) that provides the second nozzle 6 with a driving force to move along the second guide rail 7a. The second guide rail 7a is linear, extends parallel to the wafer 2 in the held rotation state, and is located on the rotational axis O of the wafer 2 in the held rotation state. The second guide rail 7a also extends perpendicular to the left-right direction and perpendicular to the front-back direction (that is, the second guide rail 7a extends linearly along the vertical direction).

[0034] The straight line horizontally connecting the center of the first guide rail 5a and the center of the second guide rail 7a (which coincides with the rotation axis O of the wafer 2 in Figure 2) is perpendicular to the wafer 2 in the held-rotating state when viewed from above (see Figure 2). The first horizontal distance D1 between the first guide rail 5a and the first surface 2a of the wafer 2 in the held-rotating state is the same as the second horizontal distance D2 between the second guide rail 7a and the second surface 2b of the wafer 2 in the held-rotating state. The first nozzle 4 and the second nozzle 6 are arranged so as to face each other when viewed from above. The straight line horizontally connecting the center of the nozzle outlet 4a of the first nozzle 4, which ejects a two-fluid jet, and the center of the nozzle outlet 6a of the second nozzle 6, which ejects a two-fluid jet (which coincides with the rotation axis O of the wafer 2 in Figure 2) is perpendicular to the wafer 2 in the held-rotating state when viewed from above (see Figure 2). The horizontal distance between the nozzle outlet 4a of the first nozzle 4 and the first surface 2a of the wafer 2 in a held and rotating state is the same as the horizontal distance between the nozzle outlet 6a of the second nozzle 6 and the second surface 2b of the wafer 2 in a held and rotating state.

[0035] As shown in Figure 4, the first nozzle 4 is tilted downward from the horizontal by a first nozzle angle θ1. In other words, the ejection direction of the first nozzle 4 is tilted downward from the horizontal by the first nozzle angle θ1 of the first nozzle 4. With this configuration, a vertically downward force is applied to the particles detached from the wafer 2 by the two-fluid jet ejected from the nozzle outlet 4a of the first nozzle 4, which is tilted downward from the horizontal. Combined with the effect of gravity, this makes it easier for the particles to fall downward from the wafer 2, and as a result, the re-adhesion of particles detached from the wafer 2 by cleaning can be further suppressed. The first nozzle angle θ1 of the first nozzle 4 can be adjusted by the angle adjustment mechanism (not shown) of the first nozzle 4. The ejection direction of the first nozzle 4 is perpendicular to the wafer 2 in the holding and rotating state when viewed from above. The first distance L1 in the front-rear direction between the nozzle outlet 4a of the first nozzle 4 and the wafer 2 in the holding and rotating state can be adjusted by the nozzle position adjustment mechanism (not shown) of the first nozzle 4. By adjusting the first distance L1, the impact pressure (the collision force between the two fluid droplets, stronger the closer the nozzle) and the spray width (the area the two fluid droplets cover, wider the further away the nozzle is) can be adjusted. Also, if the distance to the wafer 2 is too close, bounce may occur between the wafer 2 and the first nozzle 4, and the droplets containing the removed particles may reattach to the wafer 2.

[0036] The first nozzle 4 performs a first cleaning operation by scanning in a reciprocating direction along the first guide rail 5a. The first nozzle 4 efficiently performs the first cleaning operation by descending scanning while ejecting a two-fluid jet. The descending scan is preferably performed as shown in Figure 4, with the two-fluid jet hitting the first surface 2a of the wafer 2 in a held rotation state, until it passes the first surface 2a to the lower side. The first nozzle 4 preferably does not eject the two-fluid jet during the ascending scan. With these configurations, particles can be easily removed from the first surface 2a by cleaning.

[0037] The second nozzle 6 is tilted downward from the horizontal by a second nozzle angle (not shown). In other words, the ejection direction of the second nozzle 6 is tilted downward from the horizontal by the second nozzle angle of the second nozzle 6. With this configuration, a vertically downward force is applied to the particles detached from the wafer 2 by the two-fluid jet ejected from the nozzle outlet 6a of the second nozzle 6, which is tilted downward from the horizontal. Combined with the effect of gravity, this makes it easier for the particles to fall downward from the wafer 2, and as a result, the re-adhesion of particles detached from the wafer 2 by cleaning can be further suppressed. The cleaning effect of the second cleaning operation can be improved. The second nozzle angle of the second nozzle 6 can be adjusted by the angle adjustment mechanism (not shown) of the second nozzle 6. The ejection direction of the second nozzle 6 is perpendicular to the wafer 2 in the holding and rotating state when viewed from above. The second distance (not shown) in the front-to-back direction between the nozzle outlet 6a of the second nozzle 6 and the wafer 2 in the holding and rotating state can be adjusted by the nozzle position adjustment mechanism (not shown) of the second nozzle 6. The pressure and spray width can be adjusted by adjusting the second distance L2. Also, if the distance to the wafer 2 is too close, bounce may occur between the wafer 2 and the second nozzle 6, and the droplets containing the removed particles may reattach to the wafer 2.

[0038] The second nozzle 6 performs a second cleaning operation by scanning in a reciprocating direction along the second guide rail 7a. The second nozzle 6 efficiently performs the second cleaning operation by a downward scanning operation in which it ejects a two-fluid jet while descending. It is preferable that the downward scanning is performed in which the two-fluid jet strikes the second surface 2b of the wafer 2 in a held rotation state as it descends, until it passes the second surface 2b to the lower side. It is preferable that the second nozzle 6 does not eject the two-fluid jet during upward scanning. With these configurations, particles can be easily removed from the second surface 2b by cleaning.

[0039] The first cleaning operation of the first nozzle 4 and the second cleaning operation of the second nozzle 6 may be performed independently of each other, but it is preferable that they be performed synchronously. In particular, it is preferable that the first nozzle 4 and the second nozzle 6 scan at the same height and the same inclination so that the areas of the first surface 2a and the second surface 2b of the wafer 2 in a held and rotating state are simultaneously cleaned. At this time, it is also preferable that the first distance L1 and the second distance are the same, and that the spray pressure of the first cleaning operation and the spray pressure of the second cleaning operation are the same. With these configurations, it is possible to increase the spray pressure of the two-fluid jet and improve the cleaning effect while suppressing rotational wobble of the wafer 2 or damage such as distortion to the wafer 2 caused by the spray pressure.

[0040] The wafer cleaning apparatus 1 has a first spraying device 11 that sprays a first cleaning liquid in a shower-like manner onto the first surface 2a of the wafer 2 in a held and rotating state. With this configuration, the cleaning effect can be improved by wetting the first surface 2a with the first liquid before the first cleaning operation. From this viewpoint, it is preferable to spray the first liquid onto the upper end of the first surface 2a, as in this embodiment. The first liquid is not particularly limited, and in this embodiment it is ultrapure water from the viewpoint of high cleanliness. The first liquid may also be carbonated water or ammonia water.

[0041] The wafer cleaning apparatus 1 has a second spraying device 12 that sprays a second cleaning liquid in a shower-like manner onto the second surface 2b of the wafer 2 in a held and rotating state. With this configuration, the cleaning effect can be improved by wetting the second surface 2b with the second liquid before the second cleaning operation. From this viewpoint, it is preferable to spray the second liquid onto the upper end of the second surface 2b, as in this embodiment. The second liquid is not particularly limited, and in this embodiment it is ultrapure water from the viewpoint of high cleanliness. The second liquid may also be carbonated water or ammonia water.

[0042] The wafer cleaning apparatus 1 comprises a housing 13 that forms a housing space S for housing the multiple rotating rollers 3, end brushes 10, a first guide rail 5a, a first nozzle 4, a second guide rail 7a, a second nozzle 6, a first spraying device 11, a second spraying device 12, and wafers 2 in a held rotating state, and an exhaust device 14 that exhausts air from the bottom of the housing space S. With this configuration, since a two-fluid jet mist is discharged from the housing space S by the exhaust device 14, the re-adhesion of particles removed by cleaning to the wafers 2 can be suppressed and the cleaning effect can be improved. The exhaust device 14 is not particularly limited and can be composed of, for example, a fan filter unit.

[0043] The housing 13 has an intake port adjustment device 13b that adjusts the opening area of ​​the intake port 13a provided at the top of the storage space S. With this configuration, the intake and exhaust can be balanced when exhausting by the exhaust device 14, thereby improving the cleaning effect. The intake port 13a is an elongated hole that extends along the wafer 2 in a held rotation state when viewed from above, and has a first long side 13a1 and a second long side 13a2 that face each other. The intake port adjustment device 13b has a first flap 13b1 that is arranged along the first long side 13a1 of the elongated hole and can adjust the rotational position about the first long side 13a1, and a second flap 13b2 that is arranged along the second long side 13a2 of the elongated hole and can adjust the rotational position about the second long side 13a2.

[0044] The transport path for the wafers 2 to and from the wafer cleaning apparatus 1 can be set as appropriate. The wafers 2 may be transported through the intake port 13a, or a separate transport path may be provided in addition to the intake port 13a. For transport, the multiple rotating rollers 3 and end brushes 10 may be provided so as to be movable between a cleaning position and a transport position retracted from the cleaning position.

[0045] The wafer cleaning apparatus 1 has a control device (not shown) configured by a computer. The control device integrally controls the operation of the drive roller 8 (rotation timing, speed, etc.), the first drive unit (drive timing, direction, speed, etc.), the first nozzle 4 (spray timing, etc.), the second drive unit (drive timing, direction, speed, etc.), the second nozzle 6 (spray timing, etc.), the first spraying device 11 (spraying timing, etc.), the second spraying device 12 (spraying timing, etc.), the exhaust device 14 (exhaust timing, etc.), and the intake port adjustment device 13b (opening area, etc.). Preferably, the control device controls the rotation speed of the drive roller 8, the drive speed of the first drive unit, and the drive speed of the second drive unit so that a two-fluid jet is sprayed over the entire surface of the first surface 2a and the second surface 2b of the wafer 2.

[0046] The following describes the configuration of the wafer cleaning apparatus 1 in the first embodiment.

[0047] As described above, the wafer cleaning apparatus 1 includes a plurality of rotating rollers 3, a first nozzle 4, a first lifting drive unit 5, a second nozzle 6, and a second lifting drive unit 7. The description of each part is the same as in the first embodiment described above and will therefore be omitted.

[0048] Multiple rotating rollers 3 rotate around a central axis P. The central axes P are parallel to the horizontal plane and parallel to each other. Furthermore, the centers of the outer grooves 3a of all rotating rollers 3 lie on a single plane perpendicular to the horizontal plane.

[0049] The rotating roller 3 comprises two drive rollers 8 and two guide rollers 9. The two drive rollers 8 are located at the same height. The distance between the outer peripheral grooves 3a of the two drive rollers 8 is shorter than the diameter of the wafer 2 to be cleaned. With the above configuration, it is possible to support the wafer 2 by inserting the wafer 2 into the outer peripheral grooves 3a of the two drive rollers 8 and stretching the wafer 2 between the drive rollers 8.

[0050] The guide roller 9 is positioned above the drive roller 8, and the two guide rollers 9 are at the same height. The two guide rollers 9 should be positioned so that their outer peripheral grooves 3a contact the end face of the wafer 2 supported by the drive roller 8. The two guide rollers 9 may be at different heights. With the above configuration, it is possible to rotate the wafer 2 while stably holding it with the drive roller 8 and the guide rollers 9.

[0051] The first nozzle 4 and the second nozzle 6 are positioned facing each other when viewed from above, and are symmetrically positioned with respect to the plane containing the center of gravity of all the rotating rollers 3. With the above configuration, it is possible to evenly clean both sides of the wafer 2 rotated by the rotating rollers 3.

[0052] Furthermore, the configuration of the wafer cleaning apparatus 1 will be described in the following section in terms of the second embodiment. In the second embodiment, the wafer cleaning apparatus 1 has three rotating rollers 3 (two drive rollers 8 and one guide roller 9) and one end face brush 10. The rotational axis P of the rotating rollers 3 and the rotational axis Q of the end face brush 10 are parallel to each other.

[0053] The end face brush 10 is positioned such that its outer peripheral surface 10a contacts the outer peripheral edge of the wafer 2, which is held by two drive rollers 8 and one guide roller 9.

[0054] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and the embodiments described above can be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0055] 1. Wafer cleaning device 2 wafers 2a 1st page 2b 2nd side 2c Outer edge 3-rotation roller 3a Circumferential groove 4. Nozzle No. 1 4a Nozzle outlet 5. First lifting drive unit 5a First guide rail 6. Second nozzle 6a Nozzle outlet 7. Second lifting drive unit 7a Second guide rail 8 drive rollers 9 Guide roller 10 End face brush 10a Brush outer surface 11 1st spraying device 12 Second spraying device 13 cabinets 13a Intake 13a1 First long side 13a2 Second long side 13b Intake port adjustment device 13b1 First flap 13b2 Second flap 14 Exhaust system D1 1st interval D2 2nd interval L1 1st distance O Wafer rotational axis P Rotation center axis of the rotating roller Q: Rotational axis of the end brush S Containment space θ Nozzle angle θ1 First nozzle angle

Claims

1. Multiple rotating rollers that hold and rotate a wafer having a first surface and a second surface opposite to it in an upright position, thereby creating a holding and rotating state, A two-fluid jet type first nozzle performs a first cleaning operation to clean the first surface of the wafer in the held and rotating state, A first lifting drive unit moves the first nozzle vertically in order to perform the first cleaning operation by scanning, A two-fluid jet type second nozzle performs a second cleaning operation to clean the second surface of the wafer in the held and rotating state, A wafer cleaning apparatus having a second lifting drive unit that moves the second nozzle in the vertical direction in order to perform the second cleaning operation by scanning.

2. The first nozzle is tilted downwards from the horizontal, The wafer cleaning apparatus according to claim 1, wherein the second nozzle is inclined downward from the horizontal direction.

3. The first lifting drive unit has a first guide rail that extends in the vertical direction and guides the vertical movement of the first nozzle, The second lifting drive unit has a second guide rail that extends in the vertical direction and guides the vertical movement of the first nozzle. The straight line connecting the first guide rail and the second guide rail in the horizontal direction is perpendicular to the wafer in the holding and rotating state when viewed from above. The wafer cleaning apparatus according to claim 1, wherein the first horizontal distance between the first guide rail and the first surface of the wafer in the holding and rotating state is the same as the second horizontal distance between the second guide rail and the second surface of the wafer in the holding and rotating state.

4. The wafer cleaning apparatus according to claim 1, wherein the first nozzle and the second nozzle perform the scanning at the same height and the same inclination to each other, thereby simultaneously cleaning regions of the first and second surfaces of the wafer in the held and rotating state that are at the same height.

5. The plurality of rotating rollers include a drive roller that applies rotational torque to the wafer, and a guide roller whose rotational axis is located above the rotational axis of the drive roller and which guides the rotation of the wafer. The wafer cleaning apparatus according to claim 1, wherein the coefficient of friction of the drive roller is greater than the coefficient of friction of the guide roller.

6. The wafer cleaning apparatus according to claim 1, further comprising an end brush for cleaning the outer peripheral end face of the wafer in the held and rotating state by contact with the outer peripheral end face.

7. The wafer cleaning apparatus according to claim 1, wherein the rotational axis of each of the plurality of rotating rollers is located below the rotational axis of the wafer in the holding rotation state.

8. A housing that forms a housing space for housing the plurality of rotating rollers, the first nozzle, the second nozzle, and the wafer in the held rotating state, The wafer cleaning apparatus according to claim 1, further comprising an exhaust device that exhausts air from the bottom of the aforementioned storage space.

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