JP2010118519A - Method for cleaning wafer, and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for a method for cleaning a wafer, by which the bevel portion of the wafer can be excellently cleaned. <P>SOLUTION: Simultaneously with a process (a) of discharging a cleaning liquid such as a thinner from an upper nozzle 93 to the bevel portion 72 on the side of a surface 70 of the wafer W from above it while rotating the wafer W by a spin chuck 11, a process (b) of cleaning the bevel portion 72 of the wafer W by discharging a cleaning liquid from a lower nozzle 40 detachably fit to a notched portion 37 provided to an inner cup 34 to the bevel portion 72 on the side of a reverse surface 71 of the wafer W or from the side end of the wafer W to a region close to the center within 3 mm outward in a radial direction of the wafer W is carried out during the cleaning of the wafer W to suppress remaining of a resist film 80 at the bevel portion 72, thereby preventing particles from sticking on the bevel portion 72. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for applying a resist film to a semiconductor wafer (hereinafter simply referred to as a “wafer”) and performing development, and a technique for cleaning a wafer of a developing apparatus.

  The process of creating a resist pattern on a wafer is generally performed using a system in which an exposure apparatus is connected to a coating and developing apparatus including a coating apparatus and a developing apparatus. In the coating apparatus, a coating solution for film formation such as a resist film (hereinafter simply referred to as a resist solution) is applied by spin coating to form a resist film on the wafer surface. At this time, the resist solution reaches the back surface of the wafer. (See FIG. 10A). If the resist solution adheres to the position where the resist pattern is not formed, it may cause generation of particles. Therefore, the edge remover nozzle discharges the solvent to the peripheral portion of the wafer surface to remove the resist film by a predetermined width from the peripheral edge (see FIG. 10 (b)), and then the back surface is cleaned by discharging a solvent from the back surface side nozzle in order to remove the resist film that has come to the back surface side.

  By the way, in the coating apparatus, in order to suppress the wrapping of the resist solution to the back side as much as possible at the time of spin coating and to suppress the generation of turbulent flow on the lower side of the wafer so that smooth evacuation can be performed, An inner cup (inner cup) having a generally mountain-shaped upper cross section is provided so as to surround the upper portion. For this reason, the back side nozzle is provided inside the inner cup, and the solvent supply position on the back side of the wafer is considerably inside from the periphery of the wafer, so that cleaning of the bevel part of the peripheral part of the wafer is sufficient. I couldn't.

  On the other hand, recently, an exposure method called immersion exposure has been introduced for the purpose of increasing the resolution of exposure due to the demand for finer and thinner device patterns. In immersion exposure, a liquid layer such as ultrapure water that transmits light is formed on the surface of the wafer, and in that state, light from the light source is irradiated through the liquid layer to form a desired circuit pattern on the resist film. It is an exposure process to transfer. In immersion exposure, high-resolution exposure processing is performed by utilizing the fact that the wavelength of light becomes shorter in water. As an example, an ArF (argon fluoride) excimer laser (wavelength of 193 nm in the atmosphere) is used. Utilizing this, exposure is performed by transmitting the laser light through the liquid layer and changing the wavelength of the laser light to 134 nm.

  However, the photoresist process to which the above-described immersion exposure is applied has the following problems. For example, when particles adhere to the bevel portion at the peripheral edge of the wafer that has undergone the resist coating process, the particles travel on the surface of the resist film through the liquid layer formed on the surface of the wafer. For this reason, the particles block the exposure, and as a result, accurate transfer of the resist pattern is hindered, and defective portions of the resist pattern are scattered on the wafer. In addition, a cleaning device for cleaning the wafer is provided separately from the coating device, and cleaning of the wafer before immersion exposure has been studied. However, even in such a cleaning device, the bevel portion can be sufficiently cleaned. It is considered difficult, and it is required to devise a device for cleaning the bevel portion.

  On the other hand, Patent Document 1 describes a cleaning method for cleaning a bevel portion of a wafer by heating the bevel portion with a ring heater and then supplying a solvent to the wafer bevel portion from the back of the wafer for cleaning. . In this cleaning method, a resist film formed at a position where a resist pattern such as a bevel portion is not formed by a ring heater is heated and embrittled, and the residue of the resist film adheres to the bevel portion by washing with a solvent. Suppressed. However, in this cleaning method, it is necessary to provide a heating means for heating the wafer, such as a ring heater, and it becomes difficult to dispose the inner cup due to the provision of the ring heater.

JP 2008-130893 (paragraph number 0032, FIG. 3)

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a technique relating to a wafer cleaning method capable of satisfactorily cleaning a bevel portion of a wafer.

The wafer cleaning method of the present invention comprises:
An inner cup is provided so as to surround the lower region of the wafer held horizontally on the substrate holding unit, and the coating film is formed on the surface of the wafer by spin coating. In the method of cleaning by discharging a cleaning solution that dissolves the film,
A step (a) of discharging the cleaning liquid from above to the bevel portion on the wafer surface side by the upper nozzle while rotating the wafer by the substrate holding portion;
At the same time as this step, the lower nozzle that is detachably fitted in the nozzle mounting notch provided in the inner cup is beveled on the back side of the wafer or a portion within 10 mm from the bevel to the center of the wafer. And a step (b) of cleaning the bevel portion of the wafer by discharging the cleaning liquid toward the radially outer side of the wafer.

  In the wafer cleaning method of the present invention, for example, before performing the step (b), the cleaning liquid is discharged to the back surface of the wafer from a back surface cleaning nozzle provided at a position closer to the center side of the wafer than the lower nozzle. It is good also as performing a process. Further, in the wafer cleaning method of the present invention, for example, before performing the step (b), a step of discharging a cleaning liquid to remove the coating film on the peripheral edge of the wafer with a predetermined width from the upper nozzle may be performed. Good.

  In the wafer cleaning method of the present invention, for example, the inner cup has a protrusion formed along the circumferential direction at the top and an inclined surface extending outward from the lower end of the protrusion along the circumferential direction. The lower nozzle includes a portion corresponding to the protruding portion and a portion corresponding to the inclined surface so as to form a part of the inner cup in a pseudo manner, and discharges to the portion corresponding to the protruding portion. An outlet may be formed.

In the wafer cleaning method of the present invention,
In a method for cleaning a bevel portion of a wafer on which a coating film is formed,
Discharging the cleaning liquid toward the radially outer side of the wafer to the bevel portion on the wafer surface side or a portion within 5 mm from the bevel portion toward the center of the wafer while rotating the wafer by the substrate holding portion; ,
Simultaneously with this step, a step of discharging the cleaning liquid toward the radially outer side of the wafer to the bevel portion on the back surface side of the wafer or a portion within 10 mm near the center of the wafer from the bevel portion by the lower nozzle is included. It is said.

  In the wafer cleaning method of the present invention, for example, an inner cup is provided so as to surround a lower region of the wafer held horizontally by the substrate holding portion, and the lower nozzle is a nozzle mounting cut provided on the inner cup. It may be detachably fitted to the notch. In the wafer cleaning method of the present invention, for example, the cleaning of the bevel portion of the wafer may be performed on the wafer before immersion exposure by applying a resist film. In the wafer cleaning method of the present invention, for example, in the step of discharging the cleaning liquid from the upper nozzle toward the radially outer side of the wafer, the cleaning liquid is discharged from a direction of 10 degrees to 20 degrees when viewed from the wafer surface. It is characterized by that.

  The storage medium of the present invention stores a computer program used in a cleaning apparatus for cleaning a wafer by holding the wafer on a substrate holder and supplying a cleaning liquid to the bevels on the front and back surfaces of the wafer while rotating the wafer. The computer program is characterized in that a group of steps is configured to execute the above-described wafer cleaning method.

  According to the present invention, in a coating film forming apparatus that forms a coating film such as a resist film by spin coating, a notch for mounting a nozzle is formed in an inner cup surrounding a lower region of the wafer, and is detachable here. Since the lower nozzle is fitted, the cleaning liquid can be discharged from the lower nozzle to or near the bevel portion of the wafer. Then, cleaning liquid is discharged from the upper nozzle to the bevel portion on the wafer surface side while rotating the wafer, and at the same time, the cleaning liquid is discharged from the lower nozzle to the bevel portion on the wafer back side or in the vicinity thereof. Can be performed satisfactorily.

  According to still another aspect of the present invention, in a method for cleaning a bevel portion of a wafer on which a coating film is formed, a cleaning liquid is discharged outwardly to or near the bevel portion on the wafer surface side by an upper nozzle while rotating the wafer. At the same time, since the cleaning liquid is discharged outwardly to or near the bevel portion on the wafer surface side by the lower nozzle, the wafer bevel portion can be cleaned well. In this case, by providing an inner cup on the lower side of the wafer in the cleaning apparatus, it is possible to prevent the cleaning liquid from entering the back side of the wafer, and a notch for mounting the nozzle is formed in the inner cup, which is detachably mounted on the lower side. By fitting the nozzle, the cleaning liquid can be discharged from the lower nozzle to the bevel portion of the wafer or the vicinity thereof. Thus, since the bevel portion of the wafer is cleaned well, the decrease in yield can be suppressed by performing the cleaning according to the present invention before the immersion exposure process.

  A coating apparatus having a mechanism for carrying out the wafer cleaning method of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 3, the coating apparatus according to the present embodiment includes a spin chuck 11 that is a wafer holding unit that sucks and holds the center of the back surface of a wafer (substrate) W to be processed and holds it horizontally, and the wafer. On the W surface, for example, a supply nozzle 14 for supplying a solvent for a coating film such as a resist solution and a cup body 3 for suppressing scattering of mist of the resist solution scattered from the wafer W surface are provided. These devices are housed in a housing (not shown) in which, for example, a downflow of clean air is formed.

  The spin chuck 11 is connected to a spin chuck motor 13 that is a driving mechanism via a shaft portion 12, and is configured to be rotatable and raised, for example, clockwise when viewed from the top while holding the wafer W. . The wafer W is transferred to the coating apparatus by an external transfer arm (not shown), and can be transferred onto the spin chuck 11 by a cooperative action with a lift pin (not shown) provided on the side of the spin chuck 11. . The supply nozzle 14 faces, for example, the central portion of the surface of the wafer W, and plays a role of supplying a resist solution conveyed from a supply unit (not shown) to the surface of the wafer W.

  As shown in FIG. 2, the supply nozzle 14 includes a nozzle arm 14a, a nozzle drive unit 14b, and the like. The nozzle drive unit 14b is configured to move while being guided by a guide rail 9 provided in the housing. Yes. The supply nozzle 14 moves in accordance with the movement of the nozzle drive unit 14b. Further, during the period when the resist solution is not supplied, it is retracted onto the nozzle bus 14c, which is a retracting position provided on the side of the cup body 3, so that it does not interfere with the loading / unloading operation of the wafer W by the transfer arm or the like. ing.

  The cup body 3 serves to prevent the mist scattered from the wafer W from being scattered by rotating the wafer W during spin coating or the like, and to discharge the mist and drain to the outside of the coating apparatus. The cup body 3 includes an outer cup 31 having a donut-shaped double cylindrical structure, and an inner cup 34 installed on a cylinder inside the outer cup 31. As shown in FIG. 1, the outer cup 31 is provided so as to surround the spin chuck 11, and the upper end side of the side peripheral surface is inclined inward, and the tip of the inclined portion is the airflow taken into the cup body 3. A regulating portion 31b for adjusting the flow direction is provided. On the other hand, a recess-shaped liquid receiving portion 31a is formed on the bottom side of the outer cup 31, and a drain port 32 for discharging a drain of resist solution or the like is passed through the bottom of the cup 3 For example, two exhaust ports 33 for exhausting the airflow are provided. The drain port 32 and the exhaust port 33 are connected to the drain pipe 15 and the exhaust pipe 16, respectively, and an air stream including a drain such as a resist solution and mist is discharged from the coating apparatus. Here, the exhaust port 33 extends upward in the outer cup 31, and forms an overflow prevention wall 33 a for preventing drain overflow from the outer cup 31 to the exhaust pipe 16.

  As shown in FIGS. 1 and 3, a circular plate 18 surrounding the shaft portion 12 of the spin chuck 11 is provided on the lower side of the spin chuck 11, and an inner cup 34 is formed in a ring shape around the circular plate 18. Is arranged. A cross-sectional shape is formed in a mountain shape at the top of the inner cup 34, and a protrusion 36 protrudes outward from the top of this mountain-shaped portion, that is, the upper edge of the inner cup 34. The protrusions 36 serve to block the back surface of the wafer W held on the spin chuck 11 from the internal space of the cup body 3 and suppress the inflow of the mist flowing through the cup body 3 to the back surface side of the wafer W. Here, in a state where the wafer W is held on the spin chuck 11, the inner cup 34 is provided so as to surround the lower region of the wafer W, and the distance between the back surface of the wafer W and the tip of the protrusion 36 is, for example, 1. It is comprised so that it may become 0-1.5 mm. Further, on the upper surface of the protrusion 36 formed in a mountain shape, as shown in FIG. 3, two notches 37 are provided opposite to each other across the center of the inner cup 34. The lower nozzle 40, which will be described later, can be detachably fitted inside and mounted.

  As shown in FIG. 1, an end plate 35 extending downward to enter the liquid receiving portion 31 a of the outer cup 31 is provided on the outer end surface of the inner cup 34, and a part of the resist solution scattered from the wafer W is provided. As a drain, it is guided to the liquid receiving portion 31a along the surfaces of the inner cup 34 and the end plate 35. The circular plate 18 is supported by, for example, a cylindrical support portion 18a that can be inserted inside the donut-shaped cup body 3, and the shaft portion 12 that supports the spin chuck 11 described above is supported inside the support portion 18a. And a spin chuck motor 13 and the like are stored. A back surface cleaning nozzle 19 for supplying a cleaning liquid to the back surface of the wafer W held on the spin chuck 11 is disposed on the circular plate 18. The back surface cleaning nozzle 19 discharges the cleaning liquid obliquely upward from the inside of the inner cup 34 toward the outside, and supplies the cleaning liquid to the back surface of the held wafer W, for example, a position 50 mm inside from the end of the wafer W. The back surface cleaning nozzle 19 is connected to a cleaning liquid tank 51 described later via a cleaning liquid supply pipe (not shown).

  The drain pipe 15 and the exhaust pipe 16 are fixed on the bottom plate 17 constituting the above-described casing, and the drain port 32 and the exhaust port 33 are formed so as to be fitted into the corresponding drain pipe 15 and the exhaust pipe 16. Yes. As shown in FIG. 4, during the cleaning operation or the maintenance of the cup body 3, the drain body 32 and the exhaust port 33 are removed from the drain pipe 15 and the exhaust pipe 16, so that the entire cup body 3 is positioned above the spin chuck 11. It can be lifted and removed from within the applicator. That is, the outer cup 31 and the inner cup 34 are configured to be detachable from the coating apparatus.

  An upper nozzle 93 for cutting the peripheral edge of the resist film by a predetermined width and performing cleaning is provided inside the housing, and is connected to the cleaning liquid tank 51 via a cleaning liquid supply pipe (not shown). Yes. The upper nozzle 93 is configured to supply a cleaning liquid (solvent) such as thinner, which dissolves the resist film that is a coating film, from the upper side to the lower side of the wafer W. The nozzle drive unit 95 is connected to and supported by the nozzle 95 and is guided by the guide rail 9 provided in the housing in the same manner as the supply nozzle 14, thereby moving between the peripheral portion of the wafer W and the nozzle bus 96. Has been. During the period when the cleaning liquid is not supplied, the cleaning liquid is retracted onto the nozzle bus 96 which is a retracting position provided on the side of the cup body 3 so as not to interfere with the loading / unloading operation of the wafer W by the transfer arm or the like. Yes.

  Furthermore, in the coating apparatus according to the present embodiment, a cleaning liquid is supplied to the back surface of the wafer W to remove the resist attached to the bevel portion that is the inclined portion of the edge portion at the back surface and the peripheral edge of the wafer W. A nozzle 40 is provided. The lower nozzle 40 is attached to one end of an arm portion 22 that moves the lower nozzle 40, and the movement of the arm portion 22 is guided by a guide portion 23. The arm part 22 and the guide part 23 are connected by a connecting member 24 attached to the other end of the arm part 22. The connecting member 24 connects the arm portion 22 so that the arm portion 22 can swing upward. Therefore, the lower nozzle 40 can move forward and backward with respect to the notch 37 and can swing upwardly of the coating device.

  Next, the configuration of the lower nozzle 40 will be described in detail with reference to FIGS. As shown in FIG. 5, the lower nozzle 40 is a substantially rectangular parallelepiped block in which an inclined surface 41 that is higher in one direction is formed at the center of the upper surface, and is inclined in one direction across the inclined surface 41. A crest plane 41a continuous from the upper end of the surface 41 and a valley plane 41b continuous from the lower end of the inclined surface 41 are formed on the other direction side. A cut portion 42 having a substantially V-shaped longitudinal section is formed on one direction side of the lower nozzle 40. The lower nozzle 40 is fitted and attached to the notch 37 of the inner cup 34 in a state where a cleaning liquid supply pipe 52 (see FIG. 1) described later is connected as shown in FIG. Yes.

  The lower nozzle 40 is integrated with the chevron portions at both ends in the circumferential direction of the notch 37 in a state where it is attached to the notch 37 so as to form a part of the inner cup 34 in a pseudo manner. The inner cup 34 has a shape corresponding to the shape of the inner cup 34. The mountain plane 41 a functions as a part of the protrusion 36 of the inner cup 34, and the inclined surface 41 functions as a part of the inner inclined surface of the inner cup 34. Further, the lower inclined surface 42a of the cut portion 42 shown in FIG. 5 and the inner wall surface 42b of the cut portion 42 are outer sides extending outward from the lower ends of the projections 36 of the inner cup 34 as shown in FIG. An inclined surface and a part of the outer wall surface of the protrusion 36 of the inner cup 34 are formed.

  A depression 45 is provided at the approximate center of the end of the mountain plane 41a facing the inclined surface 41. The recess 45 includes a first inclined surface 45a formed on the opposite side of the rotation direction of the wafer W of the spin chuck 11 (see FIG. 7), and a first inclined surface 45a facing the first inclined surface 45a. And a second inclined surface 45b having a gentler inclination. A cleaning liquid discharge port 46 having a diameter of 0.35 mm, for example, is formed in the first inclined surface 45a.

  The cleaning liquid is discharged from the cleaning liquid discharge port 46 in the rotation direction of the wafer W. The cleaning liquid from the cleaning liquid discharge port 46 has a horizontal discharge angle of θ1 (see FIG. 7A) with respect to the back surface of the wafer W, and the horizontal plane of the cleaning liquid with respect to the tangent L2 of the wafer W perpendicular to the extension line L1 of the central axis of the lower nozzle 40. Discharge is performed such that the upper discharge angle is θ2 (see FIG. 7B). In this embodiment, θ1 is 15 degrees and θ2 is 5 degrees.

  Then, the cleaning liquid discharged from the cleaning liquid discharge port 46 is supplied to the bevel portion 72 of the wafer W from the peripheral edge side of the wafer W slightly toward the inner side, as shown in FIGS. In this embodiment, since the lower nozzle 40 is attached to the cutout portion 37 of the inner cup 34, the cleaning liquid discharge port 46 can be brought close to the bevel portion 72 of the wafer back surface 71. For this reason, the cleaning liquid can be discharged to the bevel portion 72 of the wafer back surface 71 or the vicinity thereof, and in this embodiment, the cleaning liquid discharge port is located at a position d1 that is closer to the center side of the wafer W than the end of the wafer W. 46 is formed, and the cleaning liquid is set so as to come into contact with the back surface of the wafer W at a position d2 that is closer to the center side of the wafer W than the end of the wafer W. In the present embodiment, the distance d1 is set within a range of 3 mm from the side edge of the wafer W toward the center of the wafer W, and the distance d2 is from the side edge of the wafer W toward the center of the wafer W. It is set within a range of 4.5 mm, and this range is the vicinity in this embodiment. In FIG. 7, for convenience of explanation, in order to show the lower nozzle 40 and the cleaning liquid sprayed from the lower nozzle 40 in an easy-to-understand manner, the lower nozzle 40 and the cleaning liquid are indicated by solid lines, and the wafer W is indicated by a two-dot chain line.

  The cleaning liquid discharge port 46 is connected to a cleaning liquid tank 51 via a cleaning liquid supply pipe 52 as shown in FIG. 1, and the cleaning liquid is pushed out of the cleaning liquid tank 51 by supplying an inert gas such as nitrogen gas, for example. The flow rate is adjusted by a flow rate controller 53 provided on the cleaning liquid supply pipe 52 and supplied to the cleaning liquid discharge port 46. On the upper surface side of the rotating circular plate 18 on which the arm portion 22 is provided, the cleaning liquid supply pipe 52 is composed of, for example, a flexible tube or the like, and has a sufficient margin so as not to obstruct the operation of the arm portion 22. Is given. For convenience of illustration, in FIG. 2 and subsequent drawings, a part of the cleaning liquid supply pipe 52 is omitted as appropriate.

  As shown in FIG. 3, the above-described lower nozzle 40 and the arm portion 22 and the like related to the lower nozzle 40 are provided in two sets facing each other in the diametrical direction on the upper surface of the circular plate 18. Then, the lower nozzle 40 is inserted into the notch 37 of the inner cup 34 and mounted, and the lower nozzle 40 can be positioned on the peripheral edge of the wafer W held by the spin chuck 11 (hereinafter, this position is mounted). Called location). On the other hand, when the arm portion 22 is retracted to the rear position, the lower nozzle 40 is retracted to a position inside the inner end portion of the inner cup 34 that does not interfere with the inner cup 34 when the cup body 3 is attached / detached as shown in FIG. (Hereinafter, this position is referred to as a retracted position). In the longitudinal sectional view shown in FIG. 1, for convenience of explanation, a longitudinal sectional view of both the mounting position of the lower nozzle 40 and the position away from the lower nozzle 40 is shown. It is. Further, in FIG. 1, for convenience of illustrating the lower nozzle 40 located at the mounting position and the retracted position, a part of the cleaning liquid supply pipe 52 connected to the lower nozzle 40 is omitted.

  As shown in FIG. 1, the spin chuck motor 13 of the coating apparatus, the cleaning liquid flow rate controller 53, the nozzle driving unit 95, a resist solution supply unit (not shown), and the like are connected to the control unit 6. The control unit 6 includes a computer including, for example, a central processing unit (CPU) and programs related to various functions of the devices provided in the coating apparatus. This program includes a group of steps (commands) for control related to the supply timing and supply amount of the resist solution, the rotation speed and rotation time of the spin chuck 11, the supply timing and supply amount of the cleaning solution, etc., based on a predetermined schedule. Etc. are incorporated. This program is stored in a storage medium such as a hard disk, a compact disk, a magnetic optical disk, or a memory card, and installed in the computer from there.

  Next, the operation of the coating apparatus of the present embodiment will be described in detail with reference to FIGS. FIG. 9 is a schematic diagram of the wafer W and the coating apparatus, and FIGS. 10 to 12 are schematic diagrams showing the vicinity of the bevel portion 72 of the wafer W in an enlarged manner. First, the wafer W transferred to the upper position of the spin chuck 11 by an external transfer arm (not shown) is transferred to the spin chuck 11 by the cooperative action with the lift pins described above.

  Then, as shown in FIG. 9A, the supply nozzle 14 is moved to a position above the center of the wafer W held on the spin chuck 11, and the wafer W is rotated at a predetermined speed by the spin chuck 11. Then, supply of the resist solution from the supply nozzle 14 is started, and so-called spin coating is performed to spread the resist solution in the radial direction of the wafer W. Then, after the supply of the resist solution is stopped, the wafer W is further rotated and the coated resist solution is shaken and dried. By the above operation, a resist film 80 as a coating film is formed on the surface 70 of the wafer W as shown in FIG. As described in the background art, the resist solution wraps around the resist film 80 formed at this time, and the resist film 80 is formed up to the peripheral portions of the bevel portion 72 and the back surface 71 of the wafer W.

  Therefore, as shown in FIG. 9B, the upper nozzle 93 is moved to the upper region of the peripheral portion of the wafer W, and a solvent (thinner) that is a cleaning liquid is transferred from the upper nozzle 93 while rotating the wafer W at a predetermined speed, for example, 1000 rpm. ). Then, while supplying the cleaning liquid, the upper nozzle 93 is moved gradually toward the outside of the wafer W, so that the resist film 80 formed on the peripheral edge portion and the bevel portion 72 of the surface 70 of the wafer W has a desired width, for example, For example, the wafer is removed by 2 mm from the boundary between the bevel portion 72 on the front surface 70 side of the wafer W and the flat surface of the front surface 70 as indicated by a broken line toward the center of the wafer W. As a result, as shown in FIG. 10B, the resist film 80 in the portion indicated by the broken line in the resist film 80 formed on the wafer W is removed. Next, the supply of the cleaning liquid from the upper nozzle 93 is stopped, and the cleaning liquid is supplied from the back surface cleaning nozzle 19 and the lower nozzle 40 toward the back surface 71 of the wafer W as shown in FIG. As a result, as shown in FIG. 10C, the resist film 80 indicated by the broken lines formed on the peripheral edge portion and the bevel portion 72 of the back surface 71 of the wafer W is removed.

  When the resist film 80 is removed by the above-described process (see FIG. 11A), the rotational speed of the wafer W is increased to a higher rotational speed than the resist film 80 coating process, for example, 2000 rpm, and the cleaning liquid is applied to the surface from the upper nozzle 93. At the same time as the supply to the bevel portion 72 on the 70 side, a cleaning process is performed in which the cleaning liquid is supplied from the lower nozzle 40 to the bevel portion 72 on the back surface 71 side to remove residues of the resist film 80 adhering to the bevel portion 72. In this cleaning step, the cleaning liquid is discharged from the upper nozzle 93 to the bevel portion 72 on the front surface 70 side of the wafer W, and at the same time, the cleaning liquid is discharged from the lower nozzle 40 to the bevel portion 72 on the back surface 71 side of the wafer W. The bevel portion 72 of the wafer W can be reliably cleaned. (Refer FIG.11 (b)).

  Thereafter, as shown in FIG. 11C, the supply of the cleaning liquid from the upper nozzle 93 is stopped, and the rotation speed of the wafer W is rotated at a slightly higher rotation speed than that of the previous cleaning, for example, 2100 rpm and from the lower nozzle 40. In this case, the cleaning liquid is continuously discharged to the same position, for example, for 5 seconds, and the bevel portion 72 on the back surface 71 side of the wafer W is cleaned. At this time, the cleaning liquid supplied from the lower nozzle 40 is supplied so as not to enter the bevel portion 72 on the front surface 70 side of the wafer W. Next, the rotational speed of the wafer W is increased to, for example, 3000 rpm and rotated for a predetermined time, for example, 5 seconds, so that the cleaning liquid is shaken and dried. Then, the dried wafer W is transferred to the transfer arm in the reverse order to that at the time of loading, and unloaded from the coating apparatus. Thereby, the resist film forming step is completed.

  In this cleaning step, since the resist solution and the mist of the cleaning solution generated by swinging and rotating the wafer W are discharged to the cup body 3, an air flow directed downward is generated in the space between the outer cup 31 and the inner cup 34. Is formed. A part of the airflow including such mist is entrained by the rotation operation of the wafer W or the like and tends to face the back surface 71 of the wafer W. On the other hand, in the present embodiment, as shown in FIG. 12, the upper part of the inner cup 34 has a mountain shape, and the gap between the wafer W and the inner cup 34 is narrow. It is difficult to enter the back surface 71 of W. Further, since the protrusion 36 protrudes toward the outer cup 31 at the top of the mountain-shaped portion, the flow direction of the entrained airflow can be changed to the outside by the protrusion 36. Therefore, the air flow including mist is blocked by the inner surfaces of the mountain-shaped portions, the protrusions 36, and the cut portions 42 of the lower nozzle 40, and enters the back surface 71 side of the wafer W as indicated by broken lines in FIG. It has become difficult to do.

  In the coating apparatus of this embodiment described above, since the lower nozzle 40 is fitted to the inner cup 34, the cleaning liquid discharge port 46 can be brought close to the periphery of the wafer W, and the bevel portion 72 on the back surface 71 side of the wafer W. Alternatively, the cleaning liquid can be discharged in the vicinity thereof. Then, after cleaning the resist film 80 wrapping around the back surface 71 side of the wafer W by the back surface cleaning nozzle 19 and the lower nozzle 40, the cleaning liquid is discharged from the upper nozzle 93 and the lower nozzle 40 to the bevel portion 72 or the vicinity thereof. The bevel portion 72 is cleaned. As a result, the cleaning liquid can be reliably supplied to the bevel portions 72 on the front surface 70 and the back surface 71 to clean the bevel portions 72, so that the resist film 80 can be prevented from remaining on the bevel portions 72. Can prevent the adhesion of particles. Then, during liquid immersion exposure, it is possible to reduce pattern defects caused by particles traveling on the resist layer 80 through the liquid layer, which contributes to improvement in yield. Furthermore, since the lower nozzle 40 is formed as a part of the inner cup 34 in a pseudo manner, the air flow including the mist of the inner cup 34 is prevented from entering the back surface 71 side of the wafer W. The function of is not impaired.

  In the coating apparatus of this embodiment, the resist film is applied. However, the present invention is not limited to this. For example, even if the coating apparatus applies an insulating film, the coating apparatus applies an antireflection film. Is also applicable. In this embodiment, when cleaning the bevel portion 72, the upper nozzle 93 supplies the cleaning liquid in a state of being stopped above the peripheral portion of the wafer W. For example, the upper nozzle 93 is an embodiment of the present invention. The cleaning liquid may be supplied to the bevel portion 72 while moving the wafer toward the outside of the wafer.

[Second Embodiment]
A substrate cleaning apparatus for carrying out the wafer cleaning method of the present invention will be described. This substrate cleaning apparatus is provided in the interface block B3 of the coating and developing apparatus as will be described later, for example. Therefore, the wafer is cleaned before being carried into an exposure apparatus B4 described later. As shown in FIGS. 13 and 14, the substrate cleaning apparatus includes, for example, a cup body 203 and a spin chuck 211 in a casing (not shown) in which a downflow of clean air is formed, as in the coating apparatus of the first embodiment. , A shaft portion 212, a circular plate 218, an upper nozzle 293, and the like. The substrate cleaning apparatus also includes a control unit 206 that controls each member of the substrate cleaning apparatus, as in the coating apparatus of the first embodiment. In FIG. 13, 213 is a spin chuck motor, 217 is a bottom plate, 219 is a back surface cleaning nozzle, 231 is an outer cup, 232 is a drain port, 233 is an exhaust port, 234 is an inner cup, 251 is a cleaning liquid tank, and 252 and 296 are cleaning liquids. Supply pipes 253 and 297 indicate flow controllers, respectively. In this substrate cleaning apparatus, members other than the lower nozzle 240 and the upper nozzle 293 have substantially the same configuration as that of the coating apparatus according to the first embodiment, and therefore the following description relates to the lower nozzle 240 and the upper nozzle 293. Only the members will be described. In the second embodiment, pure water, for example, is supplied to the upper nozzle 293, the lower nozzle 240, and the back surface cleaning nozzle 219 as a cleaning liquid instead of a cleaning liquid such as thinner.

  As shown in FIGS. 13 and 14, two sets of the lower nozzles 240 are provided on the upper surface of the circular plate 218 so as to face each other in the diameter direction. The lower nozzle 240 is a substantially rectangular parallelepiped block having an upper surface 241 formed at the center of the upper surface as shown in FIG. 15, and the inner cup 234 is mounted on the notch 237 with the upper surface 241 interposed therebetween. A first inclined surface 242 and a second inclined surface 243 that is gentler than the first inclined surface 242 are formed in this order from the upper surface 241 on the side that becomes the outer wall surface. In addition, an intermediate step 247 and a lower step 248 are formed in a region on the inner side of the inner cup 234 across the upper surface 241. A connection portion (not shown) to which the cleaning liquid supply pipe 252 configured by a flexible tube or the like is connected is formed in the middle step portion 247, and the lower nozzle 240 is fixed to the inner cup 234 in the lower step portion 248. A fixing hole 249 is formed. A recess 245 is formed in the vicinity of the outer edge of the second inclined surface 243 in the X-axis direction, and a cleaning liquid discharge port 246 is provided inside the recess 245.

  The upper surface 241 is formed so as to become a part of the ring-shaped protrusion 236 when the lower nozzle 240 is fitted into the notch 237. The gap between the upper surface 241 and the back surface 71 of the wafer W is formed to be about 1 mm, and the cleaning liquid (pure water) that wraps around from the front surface 70 is constituted by the upper surface 241 and the first inclined surface 242. It has a function of preventing the vertical wall from flowing into the back surface 71 side of the wafer (inside the inner cup 234). That is, the upper surface 241 has the same function as the crest plane 41a of the lower nozzle 40 of the first embodiment.

  16, the lower nozzle 240 is fitted into the notch 237 of the inner cup 234, and is attached to the inner cup 234 by fastening a fastening member such as a bolt through the fixing hole 249, for example. The At this time, the shape of the inner cup 234 is such that the lower nozzle 240 forms a part of the inner cup 234 by integrating the described upper surface 241 and the like with the chevron portions on both sides of the notch 237 in the circumferential direction. The first inclined surface 242 and the second inclined surface 243 are respectively formed on the outer inclined surface of the inner cup 234 and a part of the outer wall surface of the protrusion 236 of the inner cup 234 as shown in FIG. Function as. Therefore, the lower nozzle 240 is integrated with the inner cup 234 in a state where the lower nozzle 240 is attached to the notch 237 in the same manner as the lower nozzle 40 of the first embodiment, and forms a part of the inner cup 234 in a pseudo manner. The lower nozzle 240 is mounted with a cleaning liquid supply pipe 252 connected thereto, and the cleaning liquid supply pipe 252 is fixed on a circular plate 218 by a pipe guide portion 223.

  The upper nozzle 293 is provided inside a housing (not shown), and is connected to the cleaning liquid tank 251 via the cleaning liquid supply pipe 296 as shown in FIGS. The upper nozzle 293 is configured to supply a cleaning liquid from above the wafer W to clean the wafer W. The upper nozzle 293 is attached obliquely so as to discharge the cleaning liquid toward one side in the moving direction of the upper nozzle 293, and the cleaning liquid supplied from the upper nozzle 293 is supplied obliquely downward. .

  In this embodiment, as shown in FIG. 17, when supplying the cleaning liquid from the lower nozzle 240 and the upper nozzle 293 to the bevel portion 72, the lower nozzle 240 is attached to the cutout portion 237 of the inner cup 234. The cleaning liquid discharge port 246 can be brought close to the bevel portion 72 on the back surface. For this reason, it is possible to discharge the cleaning liquid to the bevel portion 72 of the back surface 71 or in the vicinity thereof. In this embodiment, the cleaning liquid discharged from the cleaning liquid discharge port 246 is discharged substantially upward and the wafer W Is set so as to come into contact with the back surface of the wafer W at a position d3 that is closer to the center side of the wafer W than the end of the wafer W. The cleaning liquid supplied from the upper nozzle 293 is supplied so that the ejection angle in the vertical direction with respect to the surface 70 of the wafer W becomes θ3, and the wafer W is positioned at a position d4 that is closer to the center side of the wafer W than the edge of the wafer W. It is set to come into contact with the back of the. In the present embodiment, the distance d3 is set within a range of 2 to 5 mm from the side edge of the wafer W toward the center of the wafer W, and the distance d4 is from the side edge of the wafer W to the center of the wafer W. In the present embodiment, this range is referred to as the vicinity. In this embodiment, θ3 is 10 to 20 degrees, more preferably 15 degrees.

  In the cleaning process of the wafer W of this substrate cleaning apparatus, as shown in FIGS. 18 and 19, the wafer W is delivered to the spin chuck 211 as in the first embodiment. Next, as shown in FIG. 18A, the upper nozzle 293 is moved to a position above the center of the wafer W, and while rotating the wafer W at a predetermined speed by the spin chuck 211, the upper nozzle 293, the back surface cleaning nozzle 219, and For example, the cleaning liquid is supplied from the lower nozzle 240 for a predetermined time to clean the entire surface of the wafer W, and then the cleaning liquid supply is stopped when the cleaning of the wafer W is completed (see FIG. 19A).

  Next, as shown in FIG. 18B, the upper nozzle 293 is moved to a position above the peripheral edge of the wafer W, and the cleaning liquid is supplied from the upper nozzle 293 and the lower nozzle 240 toward the bevel portion of the wafer W. Perform cleaning. In this cleaning step, the cleaning liquid is discharged from the upper nozzle 293 to the bevel portion 72 on the front surface 70 side of the wafer W, and at the same time, the cleaning liquid is discharged from the lower nozzle 240 to the bevel portion 72 on the rear surface 71 side of the wafer W (FIG. 19 (b)).

  In the cleaning process of the bevel portion 72, for example, when the bevel portion 72 of the wafer W is cleaned only by the lower nozzle 240 as shown in FIG. 20A, as shown in FIG. It is necessary to supply the cleaning liquid from the nozzle 240 to the bevel portion 72 on the surface 70 side through the side end portion of the wafer W. When the cleaning liquid is supplied in this way, the flow of the cleaning liquid that has reached the surface 70 side of the wafer W is changed to the outer cup side by the centrifugal force acting on the wafer W, and the flow direction is turned back on the surface of the wafer W. Become. Then, there arises a problem that the particles that have flowed up to the turning point reattach to the wafer W.

  Therefore, when the cleaning liquid is supplied from the upper nozzle 293 and the lower nozzle 240 toward the bevel portion of the wafer W as in the present embodiment, the reattachment of particles can be prevented and the bevel portion 72 of the wafer W can be reliably cleaned. it can. Thereafter, as shown in FIG. 19C, the supply of the cleaning liquid from the upper nozzle 293 is stopped, and the cleaning liquid is discharged from the lower nozzle 240 to the same position as it is for 5 seconds, for example, and the bevel portion 72 on the back surface 71 side of the wafer W is formed. Washed. At this time, the cleaning liquid supplied from the lower nozzle 240 is supplied so as not to enter the bevel portion 72 on the front surface 70 side of the wafer W. Then, the cleaning liquid is shaken and dried to finish the cleaning. FIG. 18 is a schematic diagram of the wafer W and the substrate cleaning apparatus as in FIG.

  In the substrate cleaning apparatus described above, since the lower nozzle 240 is fitted to the inner cup 234 as in the coating apparatus of the first embodiment, the cleaning liquid discharge port 246 can be brought close to the periphery of the wafer W, and the wafer W The cleaning liquid can be discharged to the bevel portion 72 on the back surface 71 side or the vicinity thereof. The bevel portion 72 can be cleaned by discharging a cleaning liquid from the upper nozzle 293 and the lower nozzle 240 to the bevel portion 72 or the vicinity thereof. As a result, the cleaning liquid can be reliably supplied to the bevel portions 72 on the front surface 70 and the back surface 71 to clean the bevel portion 72, so that the adhesion of particles on the bevel portion 72 can be prevented. Then, during liquid immersion exposure, it is possible to reduce pattern defects caused by particles traveling on the resist layer 80 through the liquid layer, which contributes to improvement in yield. Further, the substrate cleaning apparatus of this embodiment is an apparatus for cleaning the wafer W immediately before being carried into the exposure apparatus, and the wafer W cleaned by the substrate cleaning apparatus is carried into the exposure apparatus as it is by the transfer arm. A great effect can be expected in reducing pattern defects during immersion exposure.

  Further, in this embodiment, the upper part of the inner cup 234 has a mountain shape, and the gap between the wafer W and the inner cup 234 is narrow, so that the entrained airflow hardly enters the back surface 71 of the wafer W. The airflow including the mist of the cleaning liquid is blocked in the flow path by these mountain-shaped portions and the mountain-shaped portions of the lower nozzle 240 formed in accordance with the shape of the inner cup 234. This makes it difficult to enter the back surface 71 side of the wafer W, thereby preventing mist from adhering to the lower portion of the wafer W and greatly suppressing the adhesion of mist to the back surface 71 of the wafer W. Can do. In the substrate cleaning apparatus of the present invention, like the inner cup 34 and the lower nozzle 40 of the first embodiment, a lower nozzle provided with a protrusion protruding toward the outer cup 231 on the top of the mountain-shaped portion and an inner nozzle A cup may be used. In that case, since it becomes possible to change the flow direction of the airflow that is involved in the rotation operation of the wafer W and flows toward the inner cup, the mist adheres to the back surface 71 of the wafer W. It becomes possible to suppress.

  Next, an example of a resist pattern forming system in which an exposure apparatus is connected to a coating / developing apparatus in which the coating apparatus and the substrate cleaning apparatus according to the present embodiment are incorporated will be briefly described. As shown in FIGS. 21 to 23, the resist pattern forming system 100 of this embodiment includes a carrier mounting block B1, a processing block B2, an interface block B3, and an exposure apparatus B4. In the carrier mounting block B1, the transfer arm A1 takes out the wafer W from the hermetically sealed carrier C1 mounted on the mounting unit 110 and transfers it to the adjacent processing block B2, and the processing block B2 by the transfer arm A1. The processed wafer W processed in step S1 is received and returned to the carrier C1.

  In the processing block B2, as shown in FIG. 22, in this example, the DEV layer, which is a development area for performing the development process, and the application of an antireflection film for forming an antireflection film formed on the lower layer side of the resist film are applied. A BCT layer that is a region, a COT layer that is a coating region that performs a coating process of a resist solution, and a TCT layer that is a coating region of an antireflection film that performs a process of forming an antireflection film formed on the upper side of the resist film. The processing block B2 is configured by layering each region in order from the bottom up.

  Each of the BCT layer and the TCT layer is a liquid processing unit for applying a resist solution for forming an antireflection film by spin coating, and a pre-processing and a post-processing for processing performed in the liquid processing unit. A processing unit group for heating and cooling systems and transfer arms A2 and A4 for transferring the wafer W between the units are provided. The COT layer is used to perform a pre-treatment and a post-treatment of a coating apparatus according to the first embodiment of the present invention that applies a resist solution for forming a resist film by spin coating, and a process performed by the coating apparatus. Heating / cooling processing unit group, a hydrophobic treatment unit for performing a hydrophobic treatment, and a transfer arm A3 for transferring the wafer W between the units.

  The DEV layer includes, for example, a developing device that is stacked in two stages in one DEV layer, and a transfer arm A5 that transfers the wafer W to the developing device. As shown in FIGS. 21 and 23, the processing block B2 is provided with a shelf unit U1 and a transfer arm A6 that can move up and down to transfer the wafer W between the respective parts of the shelf unit U1. An exposure apparatus B4 is connected to the back side of the treatment block B2 via an interface block B3. The processing block B2 and the interface block B3 are connected via a shelf unit U2, and the interface block B3 includes a transfer arm A7 configured to be movable up and down, rotatable about a vertical axis, and movable back and forth. A substrate cleaning apparatus SRS and the like according to the second embodiment of the present invention are provided.

  The flow of the wafer W in which the coating and developing processes in such a resist pattern forming system are performed is as follows. As shown in FIG. 23, first, the wafer W loaded on the carrier C1 of the carrier mounting block B1 is transferred to the transfer unit CPL2 corresponding to the BCT layer of the processing block B2 of the shelf unit U1 by the transfer arm A1. Next, the wafer W is transferred from the transfer unit CPL2 to the transfer unit CPL3 → transfer arm A3 → COT layer. After the surface of the wafer W is hydrophobized by the hydrophobizing unit, a resist film is formed by the coating apparatus. . The wafer W after the formation of the resist film is delivered to the BF3 of the shelf unit U1 by the transfer arm A3.

  Thereafter, the wafer W is transferred to the TCT layer via the transfer unit BF3 → the transfer arm A6 (see FIG. 21) → the transfer unit CPL4. After the antireflection film is formed on the resist film, the wafer W is transferred to the transfer unit TRS4. Passed. In some cases, the antireflection film on the resist film is not formed, or instead of performing the hydrophobic treatment on the wafer W, the antireflection film is formed in the BCT layer.

  In addition, a shuttle arm E which is a dedicated transfer means for directly transferring the wafer W from the transfer unit CPL11 provided in the shelf unit U1 to the transfer unit CPL12 provided in the shelf unit U2 is provided in the upper part of the DEV layer. It has been. The wafer W on which the resist film is formed is transferred by the transfer arm A6 to the transfer unit CPL11 via the transfer units BF3 and TRS4, and is transferred to the interface block B3 by the shuttle arm E via the transfer unit CPL12 of the shelf unit U2. The Note that the delivery unit with CPL in FIG. 23 also serves as a buffer unit on which a plurality of wafers W can be placed.

  Next, the wafer W is transferred to the substrate cleaning apparatus SRS by the transfer arm A7 and cleaned, and then transferred to the exposure apparatus B4 for exposure processing. Thereafter, the wafer W is returned to the processing block B2 and developed in the DEV layer, and is transferred by the transfer arm A5 to the transfer table in the access range of the transfer arm A1 in the shelf unit U1. And it returns to the carrier C1 via the delivery arm A1. In FIG. 21, S1 is a processing unit group in which a heating unit and a cooling unit are stacked. Through this process, the resist pattern forming system forms a resist pattern on the wafer W. In this resist pattern forming system, by attaching the coating apparatus and the substrate cleaning apparatus of this embodiment, it is possible to prevent the particles from adhering to the bevel portion 72, and at the time of immersion exposure, the particles travel through the liquid layer and pass through the resist film 80. Pattern defects generated by riding on the substrate can be reduced, which contributes to an improvement in yield.

  Next, an experiment conducted for confirming the effect of the lower nozzle 40 will be described. In this experiment, the coating apparatus of the first embodiment was used. In this experiment, the wafer W is placed on the spin chuck 11, the wafer W is rotated, the cleaning liquid is supplied to the wafer W from the lower nozzle 40, the rotational speed of the wafer W is gradually increased, and the cleaning liquid repels from the wafer W. The number of rotations at which the phenomenon of being skipped occurred was investigated.

  The same experiment was performed for the lower nozzle 340 having a different shape and position of the cleaning liquid discharge port 344 as shown in FIG. As shown in FIG. 24A, the lower nozzle 340 is a small block having a mountain-shaped inclined surface portions 342 and 345 on the upper surface, and a protruding portion 341 is formed by the rear inclined surface portion 345 extending forward. The cleaning liquid discharge port 344 is formed at the center of the inclined surface portion 342. As shown in FIGS. 24B and 24C, the cleaning liquid discharged from the cleaning liquid discharge port 344 has a vertical discharge angle θ1 ′ with respect to the back surface of the wafer W1, and the center of the lower nozzle 340 in the horizontal direction. The ink is discharged in a direction parallel to the tangent L12 of the wafer W1 orthogonal to the extension line L11 of the shaft. Note that θ1 'is 45 degrees. In FIG. 24B and FIG. 24C, the description of the wafer W1 and the like is simplified for convenience of explanation.

  When the lower nozzle 40 and the lower nozzle 340 are compared, the cleaning liquid is supplied at a shallow angle of 15 degrees (45 degrees conventionally) with respect to the back surface 71 of the wafer W, and the diameter of the cleaning liquid discharge port 46 is 0.35 mm. It is smaller than the diameter (0.5 mm) of the discharge port 344. Since the pressure of the supplied cleaning liquid is the same, the speed of the cleaning liquid supplied from the supply port 46 is higher than that in the prior art, and this cleaning liquid is supplied from a shallow angle with respect to the back surface 71 of the wafer W. The circumferential speed with respect to W increases. For this reason, the rotation speed of the wafer W in which the phenomenon that the cleaning liquid is rebounded by the rotation of the wafer W occurs increases.

  As a result, as shown in the experimental results of FIG. 25, the lower nozzle 340 was able to supply the cleaning liquid to the wafer W only at a rotational speed of 1200 rpm, and the lower nozzle 40 was 3400 rpm, which is about three times the conventional rotational speed. Thus, the cleaning liquid can be supplied to the wafer W. In such a coating apparatus, the supply range of the cleaning liquid is controlled by the number of rotations, and when the wafer is rotated at a high speed, the supply range of the cleaning liquid can be lowered from the back surface of the wafer. Therefore, the coating apparatus of the first embodiment has the advantage that the controllability of the cleaning range is expanded because the lower nozzle 40 is provided.

  Next, an experiment conducted for examining the effect of the wafer cleaning method of the present invention will be described with reference to FIG. FIG. 26 shows an image of the bevel portion of the wafer taken with an electron microscope. In this experiment, the substrate cleaning apparatus of the second embodiment is used, the wafer W is cleaned by the wafer cleaning method of the present embodiment, and the wafer W2 is cleaned only by the lower nozzle 240 described in FIG. The wafers W and W2 were examined for differences after cleaning. In this experiment, pure water was used as a cleaning liquid, and the wafer was rotated at the same rotational speed for cleaning for the same time, and then the amount of residual particles on the bevel portion of the wafer was examined.

  FIG. 26A shows the cleaning result when the top coat is formed on the wafers W and W2, and FIG. 26B shows the cleaning result when the top coat is not formed on the wafers W and W2. Show. The wafer W and the wafer W2 clearly have a large amount of particles adhering to the wafer W2 cleaned only by the lower nozzle 240. Furthermore, almost no adhesion of particles was observed on the wafer W cleaned by the wafer cleaning method of this embodiment. From this, it was proved that the adhesion of particles can be well prevented by cleaning the wafer W by the wafer cleaning method of this embodiment. In FIG. 26, it is a little difficult to see due to the data processing, but the difference can be clearly confirmed in the actual photograph.

It is a side view which shows the outline of the coating device of this embodiment. It is a top view which shows the outline of the coating device of this embodiment. It is a perspective view which shows the outline of the cup in the coating device of this embodiment. It is a side view explaining the state which the cup body of this embodiment rose. It is the 1st explanatory view for explaining the lower nozzle of this embodiment. It is the 2nd explanatory view for explaining the lower nozzle of this embodiment. It is the 3rd explanatory view for explaining the lower nozzle of this embodiment. It is the 4th explanatory view for explaining the lower nozzle of this embodiment. It is the 1st explanatory view for explaining the application process of the resist film of this embodiment. It is the 2nd explanatory view for explaining the application process of the resist film of this embodiment. It is the 3rd explanatory view for explaining the application process of the resist film of this embodiment. It is explanatory drawing for demonstrating the effect | action of the inner cup and lower nozzle of this embodiment. It is a side view of the board | substrate cleaning apparatus which concerns on other embodiment of this invention. It is a top view of the substrate cleaning device of other embodiments. It is explanatory drawing for demonstrating the lower nozzle of other embodiment. It is explanatory drawing for demonstrating the lower nozzle of other embodiment. It is explanatory drawing for demonstrating supply of the washing | cleaning liquid of other embodiment. It is a 1st explanatory view for explaining a substrate cleaning method of other embodiments. It is the 2nd explanatory view for explaining the substrate cleaning method of other embodiments. It is the 3rd explanatory view for explaining the substrate cleaning method of other embodiments. It is a top view of the resist pattern formation apparatus with which the coating device and board | substrate washing | cleaning apparatus of this invention were integrated. 1 is a perspective view of a resist pattern forming apparatus in which a coating apparatus and a substrate cleaning apparatus of the present invention are incorporated. 1 is a side view of a resist pattern forming apparatus in which a coating apparatus and a substrate cleaning apparatus of the present invention are incorporated. It is explanatory drawing for demonstrating the lower nozzle of a comparative example. It is explanatory drawing for demonstrating the difference between the lower nozzle of 1st Embodiment, and the lower nozzle of a comparative example. It is explanatory drawing for demonstrating the experiment conducted in order to investigate the effect | action of the cleaning method of the wafer of this invention.

Explanation of symbols

3 Cup body 6 Control unit 11 Spin chuck 12 Shaft unit 13 Spin chuck motor (drive mechanism)
31 Outer cup 34 Inner cup 35 End plate 36 Protruding part 37 Notch part 40 Lower nozzle 42 Notch part 45 Recessed part 45a, 45b Inclined surface 46 Cleaning liquid discharge port 70 Front surface 71 Back surface 72 Bevel part 80 Resist film 93 Upper nozzle 100 Resist pattern Forming system B1 Carrier mounting block B2 Processing block B3 Interface block B4 Exposure apparatus SRS Substrate cleaning apparatus W, W1 Wafer

Claims (9)

An inner cup is provided so as to surround the lower region of the wafer held horizontally on the substrate holding unit, and the coating film is formed on the surface of the wafer by spin coating. In the method of cleaning by discharging a cleaning solution that dissolves the film,
A step (a) of discharging the cleaning liquid from above to the bevel portion on the wafer surface side by the upper nozzle while rotating the wafer by the substrate holding portion;
At the same time as this step, the lower nozzle that is detachably fitted in the nozzle mounting notch provided in the inner cup is beveled on the back side of the wafer or a portion within 10 mm from the bevel to the center of the wafer. And a step (b) of cleaning the bevel portion of the wafer by discharging a cleaning liquid toward the radially outer side of the wafer.   2. The step of discharging a cleaning liquid to the back surface of the wafer from a back surface cleaning nozzle provided at a position closer to the center side of the wafer than the lower nozzle is performed before performing the step (b). 2. A method for cleaning a wafer according to 1.   3. The method according to claim 1, wherein before performing the step (b), a step of discharging a cleaning liquid is performed to remove the coating film on the peripheral edge of the wafer with a predetermined width from the upper nozzle. Wafer cleaning method. The inner cup has a projection formed along the circumferential direction at the top and an inclined surface extending outward from the lower end of the projection along the circumferential direction.
The lower nozzle includes a portion corresponding to the protruding portion and a portion corresponding to the inclined surface so as to form a part of the inner cup in a pseudo manner, and a discharge port is provided in the portion corresponding to the protruding portion. The wafer cleaning method according to claim 1, wherein the wafer cleaning method is formed. In a method for cleaning a bevel portion of a wafer on which a coating film is formed,
Discharging the cleaning liquid toward the radially outer side of the wafer to the bevel portion on the wafer surface side or a portion within 5 mm from the bevel portion toward the center of the wafer while rotating the wafer by the substrate holding portion; ,
Simultaneously with this step, a step of discharging the cleaning liquid toward the radially outer side of the wafer to the bevel portion on the back surface side of the wafer or a portion within 10 mm near the center of the wafer from the bevel portion by the lower nozzle is included. A method for cleaning the wafer. An inner cup is provided so as to surround the lower region of the wafer held horizontally by the substrate holding part,
6. The wafer cleaning method according to claim 5, wherein the lower nozzle is detachably fitted in a nozzle mounting notch provided in the inner cup.   The method for cleaning a wafer according to claim 5 or 6, wherein the cleaning of the bevel portion of the wafer is performed on the wafer before immersion exposure by applying a resist film.   8. The step of discharging the cleaning liquid from the upper nozzle toward the outer side in the radial direction of the wafer, the cleaning liquid is discharged from a direction of 10 degrees to 20 degrees when viewed from the wafer surface. The wafer cleaning method according to claim 1. A storage medium storing a computer program used in a cleaning apparatus for cleaning a wafer by holding a wafer on a substrate holder and supplying cleaning liquid to the bevel portions on the front and back surfaces of the wafer while rotating the wafer,
9. A storage medium comprising a group of steps configured to execute the wafer cleaning method according to claim 1 in the computer program.

Images