JP2008021983A - Method and apparatus for liquid treatment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for liquid treatment which can discharge treatment liquid quickly from a drain cup. <P>SOLUTION: The apparatus includes a substrate holder 2 which holds a wafer W horizontally and is rotatable with the wafer W; a rotation cup 4 which is formed of annular shape so as to surround the wafer W held by the substrate holder 2 and rotatable with the wafer W; a rotation mechanism 3 rotating the rotation cup 4 and the substrate holder 2 integrally; a supply nozzle 5 for surface treatment liquid, which supplies the treatment liquid onto the surface of the wafer W; a drain cup 51 which is formed of annular shape corresponding to the rotation cup 4 and which has a drain opening 60 for receiving treatment liquid discharged from the rotation cup 4 and then draining the treatment liquid; and a swirl flow forming member 32a which is inserted into the drain cup 51, and which rotates in conjunction with the rotation of the rotation cup 4 to form swirl flow in the drain cup 51, thereby guiding the treatment liquid in the drain cup 51 into the drain opening 60 with the swirl flow. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid processing apparatus and a liquid processing method for performing predetermined liquid processing on a substrate such as a semiconductor wafer.

  In a semiconductor device manufacturing process and a flat panel display (FPD) manufacturing process, a process of supplying a processing liquid to a semiconductor wafer or a glass substrate, which is a substrate to be processed, and performing liquid processing is frequently used. As such a process, for example, a cleaning process for removing particles or contamination attached to the substrate, a coating process of a photoresist solution or a developing solution in a photolithography process, and the like can be given.

  As such a liquid processing apparatus, a substrate such as a semiconductor wafer is held on a spin chuck, a processing liquid is supplied to the front surface or front and back surfaces of the wafer while the substrate is rotated, and a liquid film is applied to the front or back surface of the wafer. A single-wafer type is known in which processing is performed by forming a film.

  In this type of apparatus, the processing liquid is usually supplied to the center of the wafer, and by rotating the substrate, the processing liquid is spread outward to form a liquid film, and the processing liquid is generally released. ing. A member such as a cup surrounding the outside of the wafer is provided so as to guide the processing liquid shaken off the substrate downward, so that the processing liquid shaken off from the wafer is quickly discharged. However, when a cup or the like is provided in this way, the processing liquid may scatter as mist and reach the substrate to cause defects such as watermarks and particles.

As a technique capable of preventing such a problem, Patent Document 1 discloses a processing liquid that receives a processing liquid scattered in the outer peripheral direction from a substrate so as to rotate integrally with a rotation support unit that rotates the substrate while being horizontally supported. There is disclosed a technique in which a receiving member is provided to receive a processing liquid and guide the processing liquid to the outside for recovery. In this Patent Document 1, the processing liquid receiving member includes, in order from the substrate side, a horizontal eaves part, an inclined guide part that guides the processing liquid outward and downward, a horizontal guide part that guides the processing liquid horizontally outward, and a vertical standing part. It has a wall to be installed, and the process liquid is forced into a narrow area and discharged to the horizontal outside through the drain port provided at the corner of the process receiving member while preventing the mist from reattaching to the substrate. Furthermore, the liquid is drained through a groove extending outwardly inside the spacer disposed outside the processing liquid receiving member.
JP-A-8-1064

  By the way, in the device for rotating the liquid receiving portion described above integrally with the rotation support means, the liquid receiving portion also rotates, so that the liquid receiving portion is drained in a circumferential shape, and the annular shape that receives the drained liquid is received. A drainage cup is required.

However, when such an annular drainage cup is provided, it takes time to drain from the drainage cup through the drainage port, so when using multiple types of treatment liquids, the following problems Occurs.
i) When multiple types of processing liquids are used, the processing destination is usually switched and sorted, but it takes time until the processing liquid is discharged from the outlet after switching the processing liquid. It is difficult to determine when to switch the discharge destination.
ii) Since the processing liquid before switching into the drain cup remains for a while after switching the processing liquid, the two processing liquids before and after switching are discharged in a mixed state.

  This invention is made | formed in view of this situation, Comprising: It aims at providing the liquid processing apparatus and the liquid processing method which can discharge | emit a processing liquid from a draining cup rapidly.

  In order to solve the above-described problem, in the first aspect of the present invention, a substrate is held horizontally and a substrate holding portion that can be rotated together with the substrate and an annular shape so as to surround the substrate held by the substrate holding portion are formed. A rotating cup that forms an annular shape that can rotate with the substrate, a rotating mechanism that integrally rotates the rotating cup and the substrate holding portion, a liquid supply mechanism that supplies a processing liquid to the substrate, and an annular shape that corresponds to the rotating cup The drainage cup having a drainage port for draining the received processing liquid and receiving the processing liquid discharged from the rotating cup, and rotating the rotating cup and the substrate holder. Provided is a liquid processing apparatus comprising a swirl flow forming means for forming a swirl flow in a liquid cup and guiding the processing liquid in the drain cup to the drain port in association with the swirl flow. Do

In the second aspect of the present invention, the substrate is held horizontally and can be rotated together with the substrate, and an annular shape is formed so as to surround the substrate held by the substrate holding portion. A rotating cup that integrally rotates the rotating cup and the substrate holding unit, a liquid supply mechanism that supplies a processing liquid to the substrate,
A drainage cup having an annular shape corresponding to the rotating cup, receiving the processing liquid discharged from the rotating cup, and having a draining port for discharging the received processing liquid;
A swirling flow is formed in the draining cup by being inserted into the draining cup and rotating with the rotation of the rotating cup and the substrate holding part, and the draining cup is accompanied by the swirling flow. And a swirl flow forming member for guiding the treatment liquid in the liquid discharge port to the drainage port.

  In the second aspect, the swirl flow forming member can be configured to be provided in the rotating cup. In this case, the rotating cup is provided so as to cover an upper portion of the end portion of the substrate held by the substrate holding portion, and to cover the outside of the substrate continuously to the flange portion. The swirl flow forming member may extend continuously downward from the outer wall portion and be inserted into the drainage cup. The swirl flow forming member may be formed in a cylindrical shape along the drainage cup.

  In the first or second aspect, a downward slope can be formed in the drainage cup so that the processing liquid flows into the drainage port along the circumferential direction, and the downward slope is processed at the drainage port. It is preferable that the liquid flow is formed over a predetermined length in the circumferential direction. In the drainage port, a guide wall portion may be formed on the opposite side of the down slope, and the guide wall portion may be inclined in a direction away from the down slope with respect to the vertical line. In this case, it is preferable that the angle θ of the guide wall portion with respect to the perpendicular satisfies 0 ° <θ <90 °. Moreover, it is preferable that the top part of the said guide wall part is arrange | positioned above the termination | terminus part of the said downward slope.

  The swirl flow forming member includes a cylindrical portion arranged along an inner surface of the drainage cup, and the cylindrical portion projects inward in the radial direction of the cylindrical portion in the drainage cup. It can be set as the structure which has an inner surface without a substantial protrusion. In this case, it is preferable that the inner surface of the cylindrical portion is terminated at a lower end by a tapered portion that is inclined radially outward and downward toward the inner surface of the drainage cup. The tapered portion of the inner surface of the cylindrical portion is preferably positioned sufficiently below the bottom surface of the substrate supported by the substrate holding portion.

  The bottom of the drainage cup may be configured to be inclined so as to rise from the outside toward the inside. Furthermore, it can be configured to further include an exhaust cup provided outside the drain cup so as to surround the drain cup and exhausting mainly the gas component from the rotary cup and its surroundings. .

  In the third aspect of the present invention, the substrate is held horizontally and can be rotated together with the substrate, and a ring is formed so as to surround the substrate held by the substrate holding unit. A rotating cup that integrally rotates the rotating cup and the substrate holding unit, a liquid supply mechanism that supplies a processing liquid to the substrate, and an annular shape corresponding to the rotating cup. A liquid processing method using a liquid processing apparatus having a draining cup having a draining port for receiving the discharged processing liquid and draining the received processing liquid, and the substrate held by the substrate holding unit Supplying the processing liquid onto the substrate, rotating the rotating cup and the substrate holder while rotating the substrate supplied with the processing liquid, and the processing liquid discharged from the rotating cup A swirl flow is formed in the drain cup with the step of receiving by the liquid cup and the rotation of the rotating cup and the substrate holder, and the treatment liquid in the drain cup is accompanied by the swirl flow and the drain And a liquid treatment method characterized by comprising the step of leading to the mouth.

  In the third aspect, the swirl flow is formed by a swirl flow forming member that is inserted into the drain cup and rotates with the rotation of the rotating cup and the substrate holding portion. The swirling flow can be adjusted by the height position of the lower end of the drainage cup from the bottom of the draining cup and the rotation speed of the substrate.

  According to the present invention, when rotating the rotating cup and the substrate holding part, a swirling flow is formed in the annular drainage cup corresponding to the annular rotating cup, and the liquid is discharged along with the swirling flow. Since the treatment liquid in the cup is guided to the drainage port, the treatment liquid can be quickly discharged from the drainage cup.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, components having substantially the same function and configuration are denoted by the same reference numerals, and redundant description will be given only when necessary. Here, a case where the present invention is applied to a liquid processing apparatus that performs front and back surface cleaning of a semiconductor wafer (hereinafter simply referred to as a wafer) will be described.

  FIG. 1 is a sectional view showing a schematic configuration of a liquid processing apparatus according to a first embodiment of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is an enlarged sectional view showing an exhaust / drainage portion. The liquid processing apparatus 100 is held by a base plate 1, a wafer holder 2 that rotatably holds a wafer W that is a substrate to be processed, a rotation motor 3 that rotates the wafer holder 2, and the wafer holder 2. A rotating cup 4 that is provided so as to surround the wafer W and rotates together with the wafer holding unit 2, a surface treatment liquid supply nozzle 5 that supplies a treatment liquid to the surface of the wafer W, and a treatment liquid to the back surface of the wafer W The back surface treatment liquid supply nozzle 6 and the exhaust / drainage part 7 provided at the peripheral edge of the rotary cup 4 are provided. A casing 8 is provided so as to cover the periphery of the exhaust / drainage unit 7 and the upper portion of the wafer W. A fan filter unit (FFU) 9 is provided on the upper portion of the casing 8 so that a downflow of clean air is supplied to the wafer W held by the wafer holder 2.

  The wafer holding unit 2 includes a horizontally-rotating rotating plate 11 having a disk shape and a cylindrical rotating shaft 12 connected to the center of the back surface and extending vertically downward. A circular hole 11 a that communicates with the hole 12 a in the rotating shaft 12 is formed at the center of the rotating plate 11. And the raising / lowering member 13 provided with the back surface process liquid supply nozzle 6 is provided so that raising / lowering is possible in the hole 12a and the hole 11a. The rotating plate 11 is provided with holding members 14 for holding the outer edge of the wafer W, and as shown in FIG. 2, three of them are arranged at equal intervals. The holding member 14 is configured to hold the wafer W horizontally with the wafer W slightly floating from the rotating plate 11. The holding member 14 includes a holding portion 14a capable of holding the end surface of the wafer W, an attaching / detaching portion 14b extending from the holding portion 14a toward the center of the back surface of the rotating plate, and a rotating shaft for rotating the holding portion 14a in a vertical plane. 14c, and the upper end of the detachable portion 14b is pushed upward by a cylinder mechanism (not shown), whereby the holding portion 14a rotates outwardly and the holding of the wafer W is released. The holding member 14 is urged in a direction in which the holding portion 14a holds the wafer W by a spring member (not shown), and the wafer W is held by the holding member 14 when the cylinder mechanism is not operated.

  The rotating shaft 12 is rotatably supported by the base plate 1 via a bearing member 15 having two bearings 15a. A pulley 16 is fitted into the lower end of the rotating shaft 12, and a belt 17 is wound around the pulley 16. The belt 17 is also wound around a pulley 18 attached to the shaft of the motor 3. The rotating shaft 12 is rotated via the pulley 18, the belt 17 and the pulley 16 by rotating the motor 3.

A purge gas supply port 19 having an annular shape along the outer periphery of the rotary shaft 12 is provided immediately above the bearing member 15. The purge gas supply port 19 is connected to a purge gas flow path 20 provided along the vertical direction in the outer wall of the bearing member 15. A purge gas pipe 21 is connected to the corresponding part. Then, for example, N ₂ gas is supplied as a purge gas from a purge gas supply source (not shown) to the purge gas supply port 19 through the purge gas pipe 21 and the purge gas flow path 20. This purge gas flows from the purge gas supply port 19 to the upper side and the lower side of the rotary shaft 12, and it is possible to suppress mist from adhering to the upper portion of the rotary shaft 12 and particles from the bearing 15 a from reaching the wafer W. It has become.

  The surface treatment liquid supply nozzle 5 is held by a nozzle arm 22 so that the treatment liquid is supplied from a liquid supply tube (not shown) and discharges the treatment liquid through a nozzle hole 5a provided therein. Yes. Examples of the processing liquid to be discharged include cleaning chemicals, rinsing liquids such as pure water, and dry solvents such as IPA. One type or two or more types of processing liquids can be discharged. As shown in FIG. 2, the nozzle arm 22 is provided so as to be rotatable about a shaft 23, and a discharge position on the center and outer periphery of the wafer W and a retreat position outside the wafer W by a driving mechanism (not shown). It is possible to move between. The nozzle arm 22 is provided so as to be movable up and down. When the nozzle arm 22 rotates between the retreat position and the discharge position, the nozzle arm 22 is in a raised state, and when the treatment liquid is discharged from the surface treatment liquid supply nozzle 5, Become.

  The back surface treatment liquid supply nozzle 6 is provided at the center of the elevating member 13, and a nozzle hole 6a extending along the longitudinal direction is formed therein. A predetermined processing liquid is supplied from the lower end of the nozzle hole 6a through a processing liquid tube (not shown), and the processing liquid is discharged to the back surface of the wafer W through the nozzle hole 6a. Examples of the processing liquid to be discharged include cleaning chemicals, rinsing liquids such as pure water, dry solvents such as IPA, and the like, as with the surface processing liquid supply nozzle 5. The liquid can be discharged. A wafer support 24 for supporting the wafer W is provided at the upper end of the elevating member 13. On the upper surface of the wafer support 24, there are three wafer support pins 25 (only two are shown) for supporting the wafer W. A cylinder mechanism 27 is connected to the lower end of the back surface treatment liquid supply nozzle 6 via a connection member 26. The wafer mechanism W is moved up and down by the cylinder mechanism 27 to raise and lower the wafer W to load the wafer W. And unloading is performed.

  As shown in FIG. 3, the rotating cup 4 includes an annular flange 31 that extends obliquely upward and inward from the upper end of the rotating plate 11, and a cylindrical outer wall that extends vertically downward from the outer end of the flange 31. A portion 32 is provided. An annular gap 33 is formed between the outer wall portion 32 and the rotating plate 11, and the processing liquid (mist) in which the wafer W is rotated together with the rotating plate 11 and the rotating cup 4 and scattered from the gap 33. Guided downward. Further, as will be described later, a cylindrical swirl flow forming member 32 a is formed so as to continue to the outer wall portion 32 and extend downward of the rotating plate 11.

  A plate-shaped guide member 35 is interposed between the flange portion 31 and the rotating plate 11 at a position substantially the same height as the wafer W. As shown in FIG. 4, a plurality of openings 36 and 37 for allowing the processing liquid to pass therethrough are formed between the collar portion 31 and the guide member 35 and between the guide member 35 and the rotating plate 11, respectively. Spacer members 38 and 39 are arranged along the circumferential direction. The flange 31, the guide member 35, the rotating plate 11, and the spacer members 38 and 39 between them are screwed with screws 40.

  The guide member 35 is provided such that the front and back surfaces thereof are substantially continuous with the front and back surfaces of the wafer W. Then, when the processing liquid is supplied from the surface processing liquid supply nozzle 5 to the center of the surface of the wafer W by rotating the wafer holding member 2 and the rotating cup 4 together with the wafer W by the motor 3, the processing liquid is centrifuged by the centrifugal force. Is spread out from the periphery of the wafer W. The processing liquid shaken off from the surface of the wafer W is guided to the surface of the guide member 35 provided substantially continuously, discharged outward from the opening 36, and guided downward by the flange portion 31 and the outer wall portion 32. . Similarly, when the processing liquid is supplied to the center of the back surface of the wafer W from the back surface processing liquid supply nozzle 6 by rotating the wafer holding member 2 and the rotating cup 4 together with the wafer W, the processing liquid is centrifugally applied to the wafer W. Is spread from the periphery of the wafer W. The processing liquid spun off from the back surface of the wafer W is guided to the back surface of the guide member 35 provided substantially continuously with the back surface of the wafer W and discharged outward from the opening 37, and the flange portion 31 and the outer wall portion 32. Is led downwards. At this time, since the centrifugal force acts on the processing liquid that has reached the spacer members 38 and 39 and the outer wall portion 32, they are prevented from returning to the inside as mist.

  Further, since the guide member 35 guides the processing liquid shaken off from the front surface and the back surface of the wafer W in this way, the processing liquid detached from the peripheral edge of the wafer W is difficult to be turbulent and rotates without misting the processing liquid. It can be led out of the cup 4. As shown in FIG. 2, the guide member 35 is provided with a notch 41 at a position corresponding to the wafer holding member 14 so as to avoid the wafer holding member 14.

  The exhaust / drainage part 7 is mainly for recovering gas and liquid discharged from the space surrounded by the rotary plate 11 and the rotary cup 4, and as shown in the enlarged view of FIG. An annular drain cup 51 that receives the processing liquid discharged from the cup 4 and an annular exhaust cup 52 that is provided outside the drain cup 51 so as to surround the drain cup 51 are provided. .

  As shown in FIG. 1 and FIG. 3, the drainage cup 51 includes a vertical wall 53 provided vertically outside the rotating cup 4 in the vicinity of the outer wall portion 32, and an inner side from the lower end portion of the vertical wall 53. And a bottom 54 extending toward the top. The upper end of the vertical wall 53 extends to above the outer wall portion 32 of the rotating cup 4 and is curved along the flange portion 31. This prevents the mist in the drain cup 51 from flowing back to the wafer W side. In addition, the drain cup 51 has a partition wall 55 that extends from the bottom 54 to the vicinity of the lower surface of the rotating plate 11 and is annularly provided along the circumferential direction at a position outside the holding member 14 inside the drain cup 51. The drain cup 51 includes a main cup portion 56 that receives the processing liquid discharged from the gap 33 and a sub cup portion that receives the processing liquid dropped from the vicinity of the holding portion 14 a of the holding member 14. 57. The bottom portion 54 is divided by a partition wall 55 into a first portion 54a corresponding to the main cup 56 and a second portion 54b corresponding to the sub cup 57, both of which are directed from the outside to the inside (rotation center side). It is inclined to rise. The inner end of the second portion 54b reaches a position corresponding to the inner side (rotation center side) of the holding portion 14a of the holding member 14. The partition wall 55 serves to prevent the airflow formed by the portion of the holding member 14 protruding below the rotating plate 11 from reaching the wafer W side with mist when the rotating plate 11 rotates. Have. The partition wall 55 is formed with a hole 58 for guiding the processing liquid from the sub cup portion 57 to the main cup portion 56.

  One drainage port 60 is provided in the outermost part of the bottom 54 of the drainage cup 51, and a drainage pipe 61 is connected to the drainage port 60. The drainage pipe 61 is provided with a drainage switching unit and a suction mechanism (both not shown), and are collected or discarded separately according to the type of processing liquid. Note that a plurality of drain ports 60 may be provided.

  As shown in FIG. 5, the height along the circumferential direction of the bottom 54 of the drainage cup 51 is the same height from the drainage port 60 to the middle along the arrow A that is the rotation direction of the rotary plate 11. However, a descending slope 62 is formed over a predetermined length at the portion flowing into the drainage port 60. Thereby, the drainage from the drainage cup 51 can be performed smoothly. The slope of the bottom portion 54 may be formed over the entire surface, but in this case, the slope is gentle, so that the effect of smoothing the drainage is small, and the portion that flows into the drainage port 60 because the processing becomes difficult. It is more advantageous to form only.

  The exhaust cup 52 is provided so that the outer wall 64 provided perpendicular to the outer portion of the vertical wall 53 of the drain cup 51 and the inner portion of the holding member 14 are perpendicular to the upper end of the holding member 14. The inner wall 65, the bottom wall 66 provided on the base plate 1, and the upper wall 67 that is curved upward from the outer wall 64 and is provided so as to cover the upper side of the rotating cup 4. The exhaust cup 52 takes in and exhausts mainly gas components in and around the rotary cup 4 from an annular inlet 68 formed between the upper side wall 67 and the flange 31 of the rotary cup 4. ing. As shown in FIG. 1, an exhaust port 70 is provided below the exhaust cup 52, and an exhaust pipe 71 is connected to the exhaust port 70. A suction mechanism (not shown) is provided on the downstream side of the exhaust pipe 71 so that the periphery of the rotary cup 4 can be exhausted. A plurality of exhaust ports 70 are provided, and can be switched and used in accordance with the type of treatment liquid.

  Thus, the processing liquid is guided to the drainage cup 51 through the rotating cup 4, the gas component is guided from the introduction port 68 to the exhaust cup 52, and the drainage liquid from the drainage cup 51 and the exhaust cup 52 Since the exhaust is performed independently, it is possible to guide the drainage and the exhaust in a separated state. Further, even if mist leaks from the drain cup 51, the exhaust cup 52 surrounds the periphery thereof, so that it is quickly discharged through the exhaust port 70, and the mist is reliably prevented from leaking outside.

  As described above, the swirl flow forming member 32 a is formed so as to extend below the rotating plate 11 continuously below the outer wall portion 32 of the rotating cup 4. The swirl flow forming portion 32 a is inserted into the main cup portion 56 of the drainage cup 51, and has a function of forming a swirl flow of air in the main cup portion 56 when rotated together with the rotating plate 11. Have. By this swirl flow, the processing liquid discharged to the drain cup 51 is promptly guided to the drain port 60.

  Since the swirl flow forming member 32 a is a part of the outer wall portion 32 of the rotating cup 4, the swirling flow forming member 32 a includes a cylindrical portion disposed along the inner surface of the drainage cup 51. The cylindrical portion has an inner surface without a substantial protruding portion that protrudes radially inward in the drainage cup 51. Further, the inner surface of the cylindrical portion of the swirl flow forming member 32 a is terminated at the lower end by a tapered portion 32 e that is inclined radially outward and downward toward the inner surface of the drainage cup 51. Thereby, a steep step between the inner surface of the swirl flow forming member 32a and the inner surface of the drainage cup 51 can be eliminated. As described above, the swirling flow forming member 32a has a smooth inner surface and the step between the swirling flow forming member 32a and the draining cup 51 is eliminated, so that the processing liquid is more than necessary in the draining cup 51. No mist is generated by stimulation. The tapered portion 32e of the swirling flow forming member 32a is disposed so as to be located sufficiently below the bottom surface of the rotating plate 11 that supports the wafer W.

  Next, the operation of the liquid processing apparatus 100 configured as described above will be described with reference to FIG. First, as shown in FIG. 6A, the wafer W is delivered onto the support pins 25 of the wafer support 24 from a transfer arm (not shown) with the elevating member 13 raised. Next, as shown in FIG. 6B, the elevating member 13 is lowered to a position where the wafer W can be held by the holding member 14, and the wafer W is chucked by the holding member 14. Then, as shown in FIG. 6C, the surface treatment liquid supply nozzle 5 is moved from the retracted position to the ejection position on the center of the wafer W.

  In this state, as shown in FIG. 6D, a predetermined process is performed from the surface treatment liquid supply nozzle 5 and the back surface treatment liquid supply nozzle 6 while the holding member 2 is rotated together with the rotary cup 4 and the wafer W by the motor 3. The liquid is supplied to perform the cleaning process.

  In this cleaning process, a processing liquid is supplied to the center of the front and back surfaces of the wafer W, and the cleaning liquid spreads outside the wafer W by centrifugal force and is shaken off from the periphery of the wafer W. In this case, since the cup provided so as to surround the outside of the wafer W is the rotating cup 4 that rotates together with the wafer W, when the processing liquid shaken off from the wafer W hits the rotating cup 4, the processing liquid Since the centrifugal force acts on this, scattering (misting) unlike the case of the fixed cup hardly occurs. Then, the processing liquid that has reached the rotating cup 4 is guided downward and discharged from the gap 33 to the main cup portion 56 of the draining cup 51. On the other hand, since the hole for inserting the holding portion 14 a is provided at the attachment position of the holding member 14 of the rotating plate 11, the processing liquid is dropped from that portion into the sub-cup portion 57 of the draining cup 51.

  Since the processing liquid discharged from the rotating cup 4 during the cleaning of the wafer W is discharged from the annular gap 33 while rotating, the draining cup 51 that receives the processing liquid must be annular. Conventionally, when such an annular drainage cup is provided, there has been a problem that it takes time to drain from the drainage cup through the drainage port. By providing the swirl flow forming portion 32a, as shown in FIG. 7, a swirl flow of air can be formed in the drain cup 51 while the wafer W is rotated and processed. The treatment liquid in the drainage cup 51 can be accompanied and promptly guided to the drainage port 60. Thus, since the processing liquid discharged to the draining cup 51 can be guided to the draining port 60 with directionality, the processing liquid can be discharged from the discharging port in a short time.

  As described above, since the processing liquid can be discharged from the annular drain cup 51 in a short time, it is easy to determine the timing for switching the discharge destination when using a plurality of types of processing liquids. It is possible to prevent the two types of processing liquids from being discharged in a mixed state when the liquids are switched.

  In this case, since a part of the rotating cup 4 is the swirl flow forming portion 32a, there is no need to provide a separate member and the apparatus is not complicated. Moreover, since the downward slope 62 is formed in the part which flows into the drainage port 60 of the bottom part 54 of the drainage cup 51, the drainage from the drainage cup 51 can be performed smoothly, and processing liquid can be performed in a shorter time. Can be discharged. Further, since the bottom portion 54 of the drain cup 51 is inclined so as to rise from the outside toward the inside, the processing liquid discharged to the inside portion of the bottom portion 54 immediately flows to the outside portion and generates a liquid residue. Can be difficult.

  The flow rate of the processing liquid due to the swirling flow formed by the swirling flow forming member 32 a varies depending on the height position of the lower end thereof, and the lower the position of the lower end position is closer to the bottom 54 of the draining cup 51, The liquid flow rate can be increased. However, too close to the bottom 54 is not preferable because the liquid splash becomes large and the surroundings are easily contaminated, and the liquid remains on the bottom 54. For this reason, it is preferable that the height position of the lower end of the swirl flow forming member 32a be set to a range in which the processing liquid in the drain cup 51 can be flowed at an appropriate flow rate and the liquid splash is in an allowable range. Further, since the action and the liquid splash flowing in the drainage cup 51 in the swirl flow change depending on the rotation speed of the swirl flow forming member 32a, that is, the rotation speed of the rotation cup 4, the swirl flow is also taken into consideration. It is necessary to adjust the height position of the forming member 32a. In the case of a 300 mm wafer, the rotation speed of the wafer W is, for example, 300 to 1200 rpm, and the rotary cup 4 also rotates at the same speed. In this case, the height of the lower end of the swirl flow forming member 32a is set to the bottom 34. To about 5 to 20 mm.

  FIG. 8 is a diagram schematically showing a part of a modified example of the drainage cup applicable to the liquid processing apparatus of FIG. In this modification, the drain port 60X of the drain cup 51 and the drain pipe 61X connected to the drain cup 51 follow the flow F of the processing liquid formed by the swirl flow forming portion 32a in the drain cup 51. Composed. Specifically, a guide wall portion 82 is formed at the drain port 60X on the opposite side of the descending slope 62 of the draining cup 51, and this tilts in a direction away from the descending slope 62 with respect to the vertical line. The angle θ with respect to the normal of the guide wall portion 82 satisfies 0 ° <θ <90 °. Further, the top portion of the guide wall portion 82 is disposed above the end portion of the descending slope 62. Further, the drainage pipe 61X is connected to the drainage cup 51 with an inclination angle of the guide wall portion 82, is curved with a large radius of curvature, and extends vertically downward.

  With this configuration, the processing liquid flow F formed by the swirl flow forming portion 32a in the drainage cup 51 is smoothly guided from the drainage port 60X into the drainage pipe 61X by the guide wall portion 82. Here, when the flow F of the processing liquid meets the guide wall 82 at the liquid discharge port 60 </ b> X, the processing wall is hardly rebounded by the guide wall 82 because the guide wall 82 is inclined. As a result, the processing liquid can be efficiently guided into the drain pipe 61X, and the generation of mist can be prevented.

  According to this embodiment, when rotating the rotating cup and the substrate holding part, a swirling flow is formed in the annular drainage cup corresponding to the annular rotating cup, and the liquid is discharged along with the swirling flow. Since the treatment liquid in the cup is guided to the drainage port, the treatment liquid can be quickly discharged from the drainage cup.

  The present invention can be variously modified without being limited to the above embodiment. For example, the swirl flow forming member is not necessarily provided in the rotating cup, and may be provided in a portion that rotates as the wafer rotates. Further, in the above-described embodiment, the liquid processing apparatus for cleaning the front and back surfaces of the wafer has been described as an example. However, the present invention is not limited thereto, and may be a liquid processing apparatus for performing cleaning processing on one of the front surface and the back surface. Further, the liquid processing is not limited to the cleaning processing, and may be other liquid processing such as resist liquid coating processing and subsequent development processing. In the above embodiment, the case where a semiconductor wafer is used as the substrate to be processed has been described. However, other substrates such as a flat panel display (FPD) substrate represented by a glass substrate for a liquid crystal display device (LCD) are used. Needless to say, it is applicable.

  The present invention is effective for a cleaning apparatus for removing particles and contamination adhering to a semiconductor wafer.

1 is a cross-sectional view illustrating a schematic configuration of a liquid processing apparatus according to an embodiment of the present invention. 1 is a schematic plan view showing a liquid processing apparatus according to an embodiment of the present invention with a part cut away. Sectional drawing which expands and shows the exhaust_gas | exhaustion / drainage part of the liquid processing apparatus of FIG. The figure for demonstrating the attachment state of the rotating cup and guide member of the liquid processing apparatus of FIG. The figure which shows typically a part of drainage cup of the liquid processing apparatus of FIG. The figure for demonstrating the processing operation of the liquid processing apparatus which concerns on one Embodiment of this invention. The schematic diagram for demonstrating the principle of this invention. The figure which shows typically a part of modification of the drainage cup applicable to the liquid processing apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Base plate 2; Wafer holding part 3; Rotating motor 4; Rotating cup 5; Surface treatment liquid supply nozzle 6; Back surface treatment liquid supply nozzle 7; Exhaust / drainage part 8; Casing 9;
DESCRIPTION OF SYMBOLS 11; Rotating plate 12; Rotating shaft 13; Elevating member 14; Holding member 31; Gutter part 32; Outer wall part 32a; Swirling flow forming member 33; Gap 35; Guide member 51; Wall 54; Bottom 60; Drainage port 62; Slope 100; Liquid processing apparatus W; Wafer

Claims (17)

A substrate holding unit that holds the substrate horizontally and can rotate with the substrate;
An annular so as to surround the substrate held by the substrate holding unit, and a rotating cup having an annular shape that can rotate with the substrate;
A rotation mechanism for integrally rotating the rotary cup and the substrate holding part;
A liquid supply mechanism for supplying a processing liquid to the substrate;
A drainage cup having an annular shape corresponding to the rotating cup, receiving the processing liquid discharged from the rotating cup, and having a draining port for discharging the received processing liquid;
When rotating the rotating cup and the substrate holding part, a swirling flow is formed in the draining cup, and the swirling flow leads the processing liquid in the draining cup to the draining port in association with the swirling flow. And a forming means. A substrate holder that holds the substrate horizontally and can rotate with the substrate;
An annular so as to surround the substrate held by the substrate holding unit, and a rotating cup having an annular shape that can rotate with the substrate;
A rotation mechanism for integrally rotating the rotary cup and the substrate holding part;
A liquid supply mechanism for supplying a processing liquid to the substrate;
A drainage cup having an annular shape corresponding to the rotating cup, receiving the processing liquid discharged from the rotating cup and having a draining port for discharging the received processing liquid;
A swirling flow is formed in the draining cup by being inserted into the draining cup and rotating with the rotation of the rotating cup and the substrate holding part, and the draining cup is accompanied by the swirling flow. And a swirl flow forming member for guiding the treatment liquid in the liquid to the drainage port.   The liquid processing apparatus according to claim 2, wherein the swirl flow forming member is provided in the rotating cup.   The rotating cup includes a flange portion provided to cover an upper portion of the end portion of the substrate held by the substrate holding portion, and an outer wall portion provided to cover the outside of the substrate continuously to the flange portion. The liquid processing apparatus according to claim 3, wherein the swirl flow forming member extends continuously downward from the outer wall portion and is inserted into the drainage cup.   The liquid processing apparatus according to claim 3, wherein the swirl flow forming member is formed in a cylindrical shape along the drainage cup.   The downflow slope is formed in the said drainage cup so that a process liquid may flow into the said drainage port along the circumferential direction, The Claim 1 characterized by the above-mentioned. Liquid processing equipment.   The liquid processing apparatus according to claim 6, wherein the down slope is formed over a predetermined length in a circumferential direction at a portion where the processing liquid flows into the drain port.   8. The drainage port according to claim 7, wherein a guide wall portion is formed on an opposite side of the down slope at the drainage port, and the guide wall portion is inclined in a direction away from the down slope with respect to a vertical line. The liquid processing apparatus as described.   The liquid processing apparatus according to claim 8, wherein an angle θ of the guide wall portion with respect to the perpendicular satisfies 0 ° <θ <90 °.   The liquid processing apparatus according to claim 8 or 9, wherein a top portion of the guide wall portion is disposed above a terminal portion of the down slope.   The swirl flow forming member includes a cylindrical portion arranged along an inner surface of the drainage cup, and the cylindrical portion projects inward in the radial direction of the cylindrical portion in the drainage cup. The liquid processing apparatus according to claim 2, wherein the liquid processing apparatus has an inner surface that does not have a substantial protrusion.   The liquid processing apparatus according to claim 11, wherein the inner surface of the cylindrical portion is terminated at a lower end by a tapered portion that is inclined radially outward and downward toward the inner surface of the draining cup. .   The liquid processing apparatus according to claim 12, wherein the tapered portion of the inner surface of the cylindrical portion is located sufficiently lower than a bottom surface of the substrate supported by the substrate holding portion.   The liquid processing apparatus according to any one of claims 1 to 13, wherein a bottom portion of the drainage cup is inclined so as to rise from the outside toward the inside.   The exhaust cup is further provided outside the drain cup so as to surround the drain cup, and further includes an exhaust cup for taking in and exhausting mainly gas components from the rotary cup and its surroundings. The liquid processing apparatus of any one of Claim 14. A substrate holding portion that holds the substrate horizontally and can rotate together with the substrate, a ring-shaped rotating cup that surrounds the substrate held by the substrate holding portion, and a ring that can rotate with the substrate, and the rotating cup And a rotation mechanism for integrally rotating the substrate holding unit, a liquid supply mechanism for supplying a processing liquid to the substrate, an annular shape corresponding to the rotating cup, and receiving the processing liquid discharged from the rotating cup, A liquid processing method using a liquid processing apparatus having a drainage cup having a drainage port for draining a received processing liquid,
Supplying a processing liquid onto the substrate held by the substrate holding unit;
Rotating the substrate supplied with the processing liquid while rotating the rotating cup and the substrate holding unit;
Receiving the processing liquid discharged from the rotating cup by the draining cup;
And a step of forming a swirling flow in the draining cup together with the rotation of the rotating cup and the substrate holding unit and guiding the processing liquid in the draining cup to the draining port in association with the swirling flow. The liquid processing method characterized by performing.   The swirling flow is formed by a swirling flow forming member that is inserted into the draining cup and rotates with the rotation of the rotating cup and the substrate holder, and the draining cup at the lower end of the swirling flow forming member. The liquid processing method according to claim 16, wherein the swirling flow is adjusted according to a height position from the bottom and a rotation speed of the substrate.

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