JP2005353739A - Substrate cleaning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To conduct the uniform cleaning of the substrate surface within a short period of time with the substrate cleaning apparatus for executing the cleaning process by supplying, to the substrate, the liquid drops generated by mixing liquid and gas. <P>SOLUTION: A double-liquid nozzle 3 has a plurality of a liquid drop generator 34 to generate liquid drops of chemical liquid by mixing the chemical liquid and nitrogen gas within a nozzle body 31 and the liquid drop groups in the shape of belt (belt type liquid drop group) can be generated by allocating these liquid drop generator like a column in the first direction R1. Moreover, the front end of nozzle is provided with a shield 35 in such a manner as holding, from both sides, the belt type liquid drop group and the liquid drops splashing toward the direction which is different from the first direction R1 from each of a plurality of liquid drop generator 34 is shielded by the shield 35. Therefore, the belt type liquid drop group is supplied to the substrate W through restriction in the width in the direction R2 (second direction) almost crossing orthogonally the allocating direction of the liquid drop generator 34. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cleaning apparatus for semiconductor wafers, glass substrates for liquid crystal display devices, PDP (plasma display panel) substrates, or various substrates such as glass substrates and ceramics for magnetic disks (hereinafter simply referred to as “substrates”). It is about.

  The manufacturing process of an electronic component such as a semiconductor device or a liquid crystal display device includes a step of repeatedly forming a fine pattern by repeatedly performing processes such as film formation and etching on the surface of the substrate. Here, in order to perform fine processing satisfactorily, it is necessary to keep the substrate surface clean, and the substrate is cleaned as necessary.

  As a substrate cleaning apparatus for cleaning a substrate as described above, a droplet jetting substrate cleaning apparatus using a two-fluid nozzle that strongly removes contaminants adhering to the substrate surface has been proposed (Patent Document). 1). In the invention described in Patent Document 1, an etching solution is introduced into the nozzle by radiating it and mixed with a gas in a mist generating portion (mixing portion), thereby making the etching solution mist. Then, by emitting a mist-like etching liquid (etching liquid droplet) from the tip of the nozzle, it is possible to realize etching of a fine pattern and to easily remove minute foreign matters (photoresist fragments, etc.). Moreover, it is possible to discharge the etching solution in a strip shape by narrowing the tip of the nozzle as necessary, or by using a flat mouth (line-like outlet). Thus, it can be expected that the cleaning process or the like is performed in a short time by discharging the etching solution in a strip shape.

Japanese Patent Laid-Open No. 4-132246 (page 4, FIG. 4)

  However, although it is expected that the throughput of the apparatus can be improved by discharging the etching solution in a strip shape, the etching solution and the gas are mixed in one mixing unit to generate a mist-like etching solution (etching solution droplet). As a result, the following problems occurred. That is, when the generated etching liquid droplets are discharged from the line-shaped discharge port at the tip of the nozzle, the discharge force of the etching liquid droplets is different between the center and the end of the line-shaped discharge port. Such contaminants could not be removed uniformly over the nozzle line direction.

  The present invention has been made in view of the above problems, and in a substrate cleaning apparatus that supplies a substrate with droplets generated by mixing a liquid and a gas and performs a cleaning process, the substrate surface is uniformly cleaned in a short time. An object of the present invention is to provide a substrate cleaning apparatus that can perform the above-described process.

  A substrate cleaning apparatus according to the present invention is a substrate cleaning apparatus that performs a cleaning process on a substrate by supplying liquid droplets generated by mixing liquid and gas to the surface of the substrate. In order to achieve the above, a plurality of droplet generation units that generate droplets by mixing a liquid and a gas are provided, and the plurality of droplet generation units are arranged in a row in the first direction, thereby forming a strip-shaped liquid A two-fluid nozzle that generates a droplet group and supplies the strip-shaped droplet group to the substrate, a liquid supply unit that supplies a liquid to a plurality of droplet generation units, and a gas that supplies a gas to the plurality of droplet generation units Supply means.

  In the invention configured as described above, since a plurality of droplet generation units are arranged in a line, the droplets generated by each droplet generation unit are arranged in a band to form a band-shaped droplet group to form a substrate. To be supplied. For this reason, the cleaning range is wide and the substrate can be cleaned in a short time. As a result, the throughput of the apparatus can be improved. Moreover, since the two-fluid nozzle has a plurality of droplet generation units, it is possible to generate and discharge droplets in each droplet generation unit. For this reason, by arranging a plurality of droplet generation units in a row, it is possible to equalize the ejection moment of the droplets in the arrangement direction (first direction) of the droplet generation units. Specifically, when the liquid droplets are ejected in a line from the single liquid droplet generation unit in the first direction, the liquid droplet generation unit has a line at the end portion and the central portion of the line discharge port. The distance to the end of the liquid discharge port is inevitably larger than the distance from the droplet generation unit to the center of the line discharge port, and the liquid droplet ejection force in the first direction becomes non-uniform. . On the other hand, according to the present invention, a plurality of droplet generation units are arranged in a row to connect the droplets generated by the droplet generation units to have a predetermined width in the first direction. Since the droplet group is generated, the distance until the droplet is ejected from the droplet generation unit can be made uniform between the end portion and the center portion in the line direction (first direction). This makes it possible to equalize the ejection force of the droplets in the first direction, and the strip droplets are uniformly supplied to the substrate in the first direction. As a result, the substrate surface can be cleaned uniformly in a short time.

  Here, the apparatus further includes a relative movement unit that relatively moves the substrate and the two-fluid nozzle in a second direction different from the first direction, and the two-fluid nozzle further includes a regulation unit that regulates the width of the band-shaped droplet group in the second direction. In this case, the substrate is relatively moved in a direction (second direction) different from the arrangement direction (first direction) of the droplet generation units, and the strip-shaped droplet group in a state where the width in the second direction is regulated. Is supplied to the substrate to clean the substrate. Therefore, it is possible to limit the radiation range of the strip droplet group to the substrate in the relative movement direction (second direction) of the substrate, that is, the cleaning direction of the substrate, and to stabilize the strip droplet group in the radiation range. The substrate can be supplied. As a result, the substrate surface can be reliably cleaned while suppressing the reattachment of particles, such as dust and slurry, to the substrate due to the unnecessarily widening of the radiation range of the strip droplet group on the substrate.

  Specifically, the droplets supplied to the substrate bounce off the substrate surface, and the droplets trapping the particles are not discharged out of the substrate, but a part thereof floats as mist. The mist may reattach to the downstream side (the substrate after cleaning) in the relative movement direction (second direction) of the substrate, but the restricting means sets the radiation range of the band-like droplet group to the substrate in the second direction. By restricting in step, it is possible to reduce the scattering of droplets over a wide range on the substrate surface. Further, the regulating means regulates the width of the strip droplet group in the second direction, so that the strip droplet group is converged in the second direction. For this reason, a droplet can be stably supplied to a substrate. As a result, it is possible to clean the substrate surface uniformly and reliably while ensuring the cleaning width necessary for cleaning the substrate W (the width of the band-like droplet group in the first direction). Here, as the restricting means, for example, the droplets scattered in the direction different from the first direction from each of the plurality of droplet generation units are blocked in the second direction, and the width of the strip droplet group in the second direction is regulated. Anything is acceptable.

  Moreover, while being attached to a two-fluid nozzle, you may provide the atmosphere interruption | blocking means spaced apart from the board | substrate, facing the board | substrate. By adopting such a configuration, the substrate and the ambient atmosphere can be shut off while the substrate can be uniformly cleaned by the two-fluid nozzle, so that the influence of the ambient atmosphere on the substrate can be prevented. . For this reason, new contamination to the substrate can be more effectively prevented. Further, according to this configuration, it becomes easy to manage the ambient atmosphere of the substrate not only in the cleaning process but also in the subsequent rinsing process and drying process.

  Further, by providing a rotating means for rotating the substrate so that the width of the strip droplet group in the first direction is at least larger than the distance from the rotation center of the substrate to the edge of the substrate, the substrate is rotated. It is possible to efficiently clean the entire substrate surface. In addition, since it is not necessary to supply the belt-like droplet group over the entire radial direction of the substrate, the two-fluid nozzle can be configured compactly. For example, when the substrate is disk-shaped, the width of the strip droplet group in the first direction may be at least the radius of the substrate. Furthermore, since the two-fluid nozzle can be fixed and cleaned without being swung on the substrate surface, the drive mechanism and the control mechanism of the apparatus can be simplified.

  Further, the two-fluid nozzle may be configured such that the droplet generation conditions can be changed for each droplet generation unit. In this case, it is possible to obtain a desired droplet diameter and droplet ejection speed by appropriately controlling the flow rate and flow rate of the liquid or gas in each droplet generation unit according to the conditions at the time of cleaning. Cleaning can be performed. For example, when cleaning is performed by rotating the substrate, the particle removal rate becomes smaller at the outer peripheral portion of the substrate where the peripheral speed is faster, so the cleaning time is increased to make the removal rate the same as the central portion of the substrate. There is a need. In this case, the removal rate in the radial direction of the substrate can be made uniform by changing the generation conditions in the droplet generation unit corresponding to the outer peripheral portion of the substrate to increase the cleaning power. As a result, the cleaning can be performed efficiently without increasing the cleaning time.

  Here, as a mode of generating a band-shaped droplet group, a plurality of droplet generation units are arranged inside the nozzle body, and the droplet generation unit generates the droplets toward the opening provided at the tip of the nozzle body. A strip-shaped droplet group may be generated by guiding the formed droplets, or each of the plurality of droplet generation units may have a liquid discharge means inside the nozzle body, a gas discharge means adjacent to the liquid discharge means, The liquid ejected from the liquid ejecting means toward the opening provided at the tip of the nozzle body and the gas ejected from the gas ejecting means are mixed to generate droplets. A band-shaped droplet group may be generated. Further, in any aspect, by arranging the restricting means between the plurality of droplet generation units and the opening, the generated band-like droplet group is discharged in the second direction before being discharged from the opening. The width of the droplet group can be regulated and supplied to the substrate.

  According to the present invention, a plurality of liquid suitable generation units are arranged in a row to generate a strip-shaped droplet group (strip-shaped droplet group) and supply it to the substrate. Therefore, the cleaning range is wide and the substrate can be cleaned in a short time. In addition, each of the plurality of droplet generation units generates droplets and is arranged in a row in the first direction, so that the droplets are uniformly disposed in the arrangement direction (first direction) of the droplet generation units. To be supplied. As a result, the substrate surface can be cleaned uniformly in a short time.

  Further, since the width of the strip droplet group is regulated in the second direction while relatively moving the substrate and the two-fluid nozzle in the second direction different from the first direction, the second direction of the strip droplet group to the substrate is controlled. The radiation range at can be limited. For this reason, it is possible to suppress the reattachment of particles to the substrate due to the radiation range of the strip-shaped droplet group on the substrate unnecessarily widening in the second direction. Furthermore, since the band-like droplet group is converged in the second direction by regulating the width of the band-like droplet group in the second direction, the droplets can be stably supplied to the substrate. As a result, it is possible to clean the substrate surface uniformly and reliably while ensuring a necessary cleaning width in the first direction.

<First Embodiment>
FIG. 1 is a schematic view showing a first embodiment of a substrate cleaning apparatus according to the present invention. The substrate cleaning apparatus 1 is for cleaning the surface of a substrate W such as a semiconductor wafer. The spin chuck 10 rotates while holding the substrate W substantially horizontally, and a chemical solution corresponding to the “liquid” of the present invention. (For example, hydrofluoric acid, sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, ammonia, or an aqueous solution of these hydrogen peroxides) and nitrogen gas corresponding to the “gas” of the present invention are mixed to produce chemical liquid droplets, A two-fluid nozzle 3 for supplying the droplets toward the substrate W held on the spin chuck 10 and a splash guard (not shown) arranged so as to surround the spin chuck 10 are provided. The liquid used is not limited to a chemical solution, and may be pure water or ultrapure water. Further, the gas used is not limited to nitrogen gas but may be compressed air or the like.

  The spin chuck 10 includes a rotating shaft 11 disposed along the vertical direction and a disk-shaped spin base 12 attached to the upper end of the rotating shaft 11. A plurality of (for example, six) chuck pins 13 are erected on the edge of the upper surface of the spin base 12 at an appropriate interval in the circumferential direction of the spin base 12. The chuck pins 13 support the lower surface edge of the substrate W and abut on the end surface (circumferential surface) of the substrate W, so that the substrate W can be held in a state of being separated upward from the spin base 12. It has become. In this embodiment, the substrate W is mechanically held by the chuck pins 13, but the holding method of the substrate W is not limited to this. For example, the substrate W may be held by suction. .

  Further, the rotation shaft 11 of the spin chuck 10 is connected to a motor (not shown) of the rotation drive mechanism 14, and the rotation drive mechanism 14 is operated according to the motor drive by the controller 20 that controls the entire apparatus. Rotate. As a result, the substrate W held by the chuck pins 13 above the spin base 12 rotates around the rotation axis Pa together with the spin base 12. Thus, in this embodiment, the rotational drive mechanism 14 corresponds to the “rotating means” of the present invention.

  The two-fluid nozzle 3 is disposed above the spin base 12 so as to supply the liquid droplets of the chemical liquid in a strip shape to the surface of the substrate W thus rotationally driven. More specifically, the two-fluid nozzle 3 is spaced apart with its longitudinal direction (corresponding to the “first direction” of the present invention) substantially parallel to the radial direction of the substrate W, and the two-fluid nozzle 3 The chemical solution supplied from 3 toward the substrate W is fixed to the distal end side of one arm 21 in an arrangement posture that is substantially parallel to the normal direction of the substrate W (vertical direction in FIG. 1). On the other hand, a nozzle moving mechanism 23 is connected to the base end portion of the arm 21. The arm 21 can be driven to swing by operating the nozzle moving mechanism 23 in accordance with a control command from the controller 20. Thereby, the two-fluid nozzle 3 moves between a facing position (the state shown in FIG. 1) where the cleaning of the substrate W is performed facing the substrate W, and a retracted position retracted sideways from the facing position. Can do.

  As shown in FIG. 1, the two-fluid nozzle 3 is connected to a chemical solution supply source via a chemical solution pipe 24, and receives supply of the chemical solution from the chemical solution supply source. The chemical solution pipe 24 is provided with a valve 24V whose opening degree can be adjusted. In response to a command from the controller 20, the flow of the chemical solution supplied to the two-fluid nozzle 3 and the flow rate of the chemical solution are set.・ The flow rate can be adjusted. Further, a flow meter 24F is interposed downstream of the valve 24V (between the valve 24V and the two-fluid nozzle 3) in the chemical liquid pipe 24, and is introduced into the two-fluid nozzle 3 by the flow meter 24F. The flow rate of the chemical solution can be measured.

  The two-fluid nozzle 3 is supplied with high-pressure nitrogen gas from a nitrogen gas supply source via a nitrogen gas pipe 25. The nitrogen gas pipe 25 is provided with a valve 25V whose opening degree can be adjusted. In response to a command from the controller 20, the flow of the nitrogen gas supplied to the two-fluid nozzle 3 is opened and closed, and the nitrogen gas It is possible to adjust the flow rate and flow velocity of the. In the nitrogen gas pipe 25, a pressure gauge 25P and a flow meter 25F are interposed downstream of the valve 25V (between the valve 25V and the two-fluid nozzle 3) and introduced into the two-fluid nozzle 3. The pressure, flow rate, and flow rate of nitrogen gas can be measured.

  In this way, the controller 20 controls the valves 24V and 25V, so that the flow rate and flow rate of the chemical solution and nitrogen gas supplied to the two-fluid nozzle 3 can be adjusted. The two-fluid nozzle 3 receives supply of the chemical liquid and nitrogen gas whose flow rates are adjusted, generates chemical liquid droplets, and can supply the liquid droplets toward the substrate W. Thus, in this embodiment, the chemical liquid pipe 24 corresponds to the “liquid supply means” of the present invention, and the nitrogen gas pipe 25 corresponds to the “gas supply means” of the present invention.

  2 is a cross-sectional perspective view showing the configuration of a two-fluid nozzle used in the substrate cleaning apparatus of FIG. The two-fluid nozzle 3 includes a nozzle main body 31 having an opening 311 at the tip thereof, and a chemical liquid and nitrogen gas are mixed inside the nozzle main body 31 to generate a liquid droplet of the chemical liquid, and from the opening 311 to the substrate W. This is a two-fluid nozzle that discharges toward the nozzle. The nozzle body 31 includes therein a chemical solution supply pipe 32 that supplies a chemical solution and a gas supply pipe 33 that supplies nitrogen gas along the longitudinal direction R1 (first direction) of the nozzle body 31. . The chemical liquid supply pipe 32 and the gas supply pipe 33 are connected to the chemical liquid pipe 24 and the nitrogen gas pipe 25, respectively, and are supplied with the chemical liquid and the nitrogen gas from the chemical liquid supply source and the nitrogen gas supply source.

  On the side wall of the gas supply pipe 33, a plurality of gas branch pipes 33a for distributing nitrogen gas from the gas supply pipe 33 are provided in a row in the longitudinal direction. Each of the gas branch pipes 33a extends toward the nozzle tip and is connected to a droplet generation unit 34 described later. On the other hand, on the side wall of the chemical liquid supply pipe 32, a plurality of chemical liquid branch pipes 32a for distributing the chemical liquid from the chemical liquid supply pipe 32 are provided in a row corresponding to the gas branch pipes 33a in the longitudinal direction, and the end portions thereof Respectively enter the plurality of gas branch pipes 33a and extend in a direction coaxial with the pipes 33a. That is, the chemical solution branch pipe 32a and the gas branch pipe 33a are arranged coaxially sharing the central axis Q.

  The chemical branch pipe 32a and the gas branch pipe 33a have a structure in which the gas branch pipe 33a surrounds the outside of the chemical branch pipe 32a, that is, a double pipe structure in which the chemical branch pipe 32a is inserted into the gas branch pipe 33a. The nozzle body 31 has a configuration in which a plurality of the double pipe structures are arranged in a row. Accordingly, each chemical branch pipe 32a discharges the chemical liquid by receiving the supply of the chemical liquid from the chemical liquid supply source via the pipes 24 and 32, while each gas branch pipe 33a is connected to the nitrogen gas via the pipes 25 and 33. Nitrogen gas is discharged by receiving supply of nitrogen gas from a supply source. Then, on the downstream side of the end portion of the chemical branch pipe 32a in the gas branch pipe 33a, the chemical liquid and the nitrogen gas are mixed to generate a liquid droplet of the chemical liquid. As described above, the downstream side of the end portion of the chemical liquid branch pipe 32a in the gas branch pipe 33a is a liquid droplet generation section 34 that generates liquid drops of the chemical liquid, and the plurality of liquid droplet generation sections 34 are arranged in a row. It is possible to generate a droplet group (strip-shaped droplet group) in which droplets are arranged in a strip shape. Here, the strip droplet group includes a plurality of liquid droplets such that the width L (FIG. 1) of the strip droplet group in the arrangement direction R1 (first direction) of the droplet generation unit 34 is at least larger than the radius of the substrate W. It is generated by the droplet generator 34.

  Further, the other end of each droplet generation unit 34 is connected to a blocking unit 35 provided at the tip of the nozzle via a droplet discharge port 36. The blocking unit 35 is formed of a long plate at the tip of the nozzle so as to sandwich the strip droplet group from both sides along the arrangement direction R1 of the droplet generation unit 34. Further, the other end of the blocking portion 35 that extends vertically, that is, the opening 311 provided at the tip of the nozzle opens in a slit shape toward the substrate W. For this reason, the droplets scattered from each of the plurality of droplet generation units 34 in a direction different from the arrangement direction R1 of the droplet generation units 34 are blocked by the blocking unit 35. As a result, the width of the strip droplet group is regulated in the direction R2 (corresponding to the “second direction” in the present invention) substantially orthogonal to the arrangement direction of the droplet generation units 34. Note that the length of the blocking portion 35 in the axial direction Q, that is, the distance from the droplet discharge port 36 to the opening 311 is long enough to reliably regulate the width of the band-like droplet group in the second direction. It has been. In addition, the blocking unit 35 is continuously provided in the first direction (longitudinal direction R1), whereby the droplet group in the first direction is made more uniform. Thus, in this embodiment, the blocking part 35 corresponds to the “regulating means” of the present invention.

  FIG. 3 is a side view of the two-fluid nozzle used in the substrate cleaning apparatus of FIG. 2 and 3, in the two-fluid nozzle 3, the chemical liquid is supplied from the chemical liquid supply pipe 32 to the chemical liquid branch pipe 32a, and the pressurized nitrogen gas is supplied from the gas supply pipe 33 to the gas branch pipe 33a. Then, the chemical liquid and nitrogen gas are mixed in each liquid droplet generation unit 34 to generate chemical liquid droplets. Then, the droplets generated by each droplet generation unit 34 are discharged from the droplet discharge port 36, thereby generating a band-like droplet group. The generated strip-shaped droplet group is arranged in the blocking unit 35 provided at the nozzle tip from each of the plurality of droplet generation units 34 in the arrangement direction R1 of the droplet generation unit 34 (in FIG. 3, the direction perpendicular to the paper surface). The liquid droplets scattered in different directions are blocked, and the width of the band-shaped liquid droplet group is regulated and supplied to the surface of the substrate W in the direction R2 substantially perpendicular to the arrangement direction R1 of the liquid droplet generation unit 34.

  Here, since the substrate W is rotated in a state where the longitudinal direction R1 of the two-fluid nozzle 3 is substantially coincident with the radial direction of the substrate W, the substrate W is relative to the longitudinal direction R1 of the two-fluid nozzle 3. Relative movement is performed in a substantially orthogonal direction. That is, the rotational movement direction of the substrate W, that is, the cleaning direction of the substrate W is equal to the regulation direction R2 of the width of the strip droplet group. Therefore, the band-like droplet group is supplied to the substrate W with the cleaning width D (FIG. 3) in the cleaning direction of the substrate W being limited. Therefore, the range of radiation of the band-shaped droplet group to the substrate W is not unnecessarily widened in the cleaning direction of the substrate W, and the droplets are prevented from scattering over a wide range on the surface of the substrate W.

  Further description will be continued with reference to FIG. In this apparatus, when cleaning the surface of the substrate W, the substrate W held on the spin chuck 10 is rotated by the rotation drive mechanism 14, and a group of liquid droplets of a chemical solution is directed from the two-fluid nozzle 3 toward the upper surface of the substrate W. To spray. That is, by introducing high-pressure nitrogen gas into the two-fluid nozzle 3, liquid droplets of a chemical solution having a large kinetic energy can collide with the surface of the substrate W in a band shape. At this time, particles adhering to the surface of the substrate W are physically removed by the kinetic energy of the droplets. The removed particles are discharged out of the substrate W along with the flow of droplets on the substrate W from the center of the substrate W toward the end by the centrifugal force accompanying the rotation of the substrate W. In addition, since the removed particles are mainly transported to the upstream side in the relative movement direction of the substrate W (the particles on the downstream side of the substrate W also move to the upstream side of the substrate W by the rotation of the substrate W). Even if particles are reattached on the upstream side of the substrate W, they are removed again by the proceeding droplets, and are ejected out of the substrate W in the same manner along the flow of the droplets.

  As described above, in this embodiment, since the plurality of droplet generation units 34 are arranged in a row, the droplets generated by each droplet generation unit 34 are connected in a band to form a band-shaped droplet group. And supplied to the substrate W. For this reason, the washing | cleaning range is wide and it can wash | clean in a short time. More specifically, the longitudinal direction of the two-fluid nozzle 3, that is, the arrangement direction R <b> 1 (first direction) of the droplet generation unit 34 substantially coincides with the radial direction of the substrate W, and the arrangement direction of the droplet generation unit 34. Since the width L of the strip droplet group in R1 is set to be at least the radius of the substrate W, the entire surface of the substrate W can be cleaned by rotating the substrate W once. As a result, the two-fluid nozzle 3 can be made compact and the throughput of the apparatus can be improved. In addition, since the belt-like droplet group is generated from the plurality of droplet generation units 34, the supply of droplets to the substrate W in the arrangement direction R1 of the droplet generation units 34 can be made uniform. More specifically, a plurality of droplet generators 34 are arranged in a row to join the droplets generated by the droplet generators 34 so as to have a predetermined width L in the first direction. Since the group is generated, it is possible to equalize the droplet ejection force in the arrangement direction R1 (first direction) of the droplet generation unit 34. Therefore, unlike the case where droplets are ejected in a strip shape (in a line) from a single droplet generation unit in the first direction, the droplet ejection force in the line direction does not become uneven. . For example, the supply of liquid droplets to the substrate does not become uneven because the ejection momentum increases at the center in the line direction and decreases at the end. Further, it is not necessary to scan the entire surface of the substrate W by swinging the two-fluid nozzle 3 on the surface of the substrate W, and the two-fluid nozzle 3 can be fixed to perform cleaning. The drive mechanism and the control mechanism can be simplified.

  Further, in this embodiment, since the cleaning width D in the cleaning direction of the substrate W is regulated, the substrate of particles due to the radiation range of the band-like droplet group to the substrate W unnecessarily widens in the cleaning direction of the substrate W. Redeposition to W can be suppressed. That is, as already described in the section “Means for Solving the Problems”, the droplets supplied to the substrate W bounce off the surface of the substrate W, and the droplets trapping the particles float as mist. To do. The mist is scattered over the surface of the substrate W over a wide range by the air flow generated by the centrifugal force accompanying the rotation of the substrate W, and is reattached to the downstream side of the substrate W in the cleaning direction (the cleaned substrate W). That is, on the substrate W, particles are reattached on the downstream side in the cleaning direction of the substrate W while the particles are removed at the location where the droplets are supplied. As a result, particles remain on the substrate W.

  On the other hand, in this embodiment, since the radiation range of the strip droplet group to the substrate W is regulated in the cleaning direction of the substrate W, the cleaning width D in the cleaning direction of the substrate W is limited without being unnecessarily widened. Is done. For this reason, it is possible to reduce the scattering of droplets over a wide range on the surface of the substrate W. Furthermore, by regulating the width of the strip droplet group in the cleaning direction of the substrate W, the strip droplet group is converged in this direction. For this reason, it is possible to stably supply the strip-shaped droplet group to the substrate W while ensuring the cleaning width L necessary for cleaning in the radial direction of the substrate W. As a result, uniform and reliable cleaning of the surface of the substrate W can be achieved while preventing the particles from reattaching to the substrate W. In addition, the removed particles are mainly transported to the upstream side in the relative movement direction of the substrate W, and are discharged in a line shape by the traveling band-like droplet group. Can be prevented from re-adhering, and reliable cleaning can be achieved.

Second Embodiment
FIG. 4 is a diagram showing the configuration of the second embodiment of the substrate cleaning apparatus according to the present invention. The figure (a) is a side view, The figure (b) is a partial top view. The second embodiment is greatly different from the first embodiment in that a disk-shaped atmosphere blocking plate 4 is additionally provided above the substrate W held by the spin chuck 10. The atmosphere blocking plate 4 is slightly larger than the diameter of the substrate W and is integrally attached to the side of the two-fluid nozzle 3. Specifically, the two-fluid nozzle 3 is attached to the atmosphere blocking plate 4 so that the two-fluid nozzle 3 is attached in the radial direction from the center to the end, and so that the two-fluid nozzle 3 can penetrate in the thickness direction of the atmosphere blocking plate 4. A groove 41 is formed in accordance with the shape of the fluid nozzle 3. For this reason, by disposing the two-fluid nozzle 3 in the groove 41, it is possible to discharge a band-shaped droplet group from the lower surface of the atmosphere blocking plate 4 toward the surface of the substrate W. Thus, in this embodiment, the atmosphere blocking plate 4 corresponds to the “atmosphere blocking means” of the present invention.

  When the belt-like droplet group is supplied to the substrate W in the same manner as in the first embodiment, the centrifugal force accompanying the rotation of the substrate W causes the particles to ride on the flow of droplets on the substrate W from the center of the substrate W toward the end. Is discharged out of the substrate W. Then, the chemical liquid discharged from the substrate W is received by the splash guard 15 disposed around the substrate W so as to surround the substrate W, and is poured into a liquid drain tank (not shown). Here, the droplet bounced by colliding with the splash guard 15 due to the airflow accompanying the rotation of the substrate W may reach the substrate W and reattach, but the droplet is applied to the substrate W by the atmosphere blocking plate 4. Reattachment is prevented.

  As described above, in this embodiment, by providing the atmosphere blocking plate 4, it becomes possible to manage the ambient atmosphere of the substrate W during the cleaning of the substrate W and the subsequent rinsing and drying processes, as well as to the substrate W. It is possible to reliably prevent the particles from reattaching. In particular, since the two-fluid nozzle 3 used in the present invention does not have to scan the entire surface of the substrate W by swinging on the substrate W, there is no physical interference with the atmosphere blocking plate 4 and the atmosphere blocking plate 4 Coexistence with is possible. That is, since the two-fluid nozzle 3 according to the present invention can clean the entire surface of the substrate W by rotating the substrate W, the ambient atmosphere of the substrate W can be strictly controlled by using the atmosphere blocking plate 4 together. It is possible to reliably prevent new contamination such as reattachment of particles.

  Further, an inert gas such as nitrogen gas may be supplied to a space formed between the atmosphere blocking plate 4 and the substrate W in order to reliably prevent particles from reattaching to the substrate W. Thereby, the intrusion of liquid droplets due to the negative pressure in the space formed between the atmosphere blocking plate 4 and the substrate W is effectively prevented.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, a band-shaped droplet group is generated by guiding the droplet generated in each of the plurality of droplet generation units 34 toward the nozzle opening. For example, as shown in FIG. Alternatively, the liquid droplets may be generated by causing nitrogen gas to collide with the chemical liquid discharged toward the nozzle opening to generate liquid droplets.

  FIG. 5 is a diagram showing the configuration of another two-fluid nozzle of the substrate cleaning apparatus according to the present invention. This two-fluid nozzle 5 is used in place of the two-fluid nozzle 3 employed in the previous embodiment. In this embodiment, the two-fluid nozzle 5 can generate chemical liquid droplets by causing nitrogen gas to collide with the chemical liquid discharged toward the opening 511 provided at the tip thereof. The two-fluid nozzle 5 includes a chemical liquid supply pipe 52 for supplying a chemical liquid and a gas supply pipe 53 for supplying nitrogen gas along the longitudinal direction R1 (first direction) in the nozzle body 51. In the chemical liquid supply pipe 52, a plurality of chemical liquid branch pipes 52a are provided in a row in the longitudinal direction, and each chemical liquid branch pipe 52a constitutes a chemical liquid discharge nozzle 522 having a chemical liquid discharge port 521 at its tip. For this reason, when the chemical liquid is supplied from the chemical liquid supply pipe 52 to each chemical liquid branch pipe 52 a, the chemical liquid is discharged toward the substrate W from each chemical liquid discharge port 521.

  The gas supply pipe 53 is provided with a plurality of gas branch pipes 53a in a row corresponding to the chemical solution branch pipes 52a in the longitudinal direction, and each gas branch pipe 53a communicates with the gas discharge nozzle 532. Yes. The gas discharge nozzle 532 defines a ring-shaped gas passage surrounding the chemical liquid discharge nozzle 522. The tip of each gas discharge nozzle 532 is tapered and the nozzle opening faces the surface of the substrate W. For this reason, when nitrogen gas is supplied from the gas supply pipe 53 to each gas branch pipe 53 a, the nitrogen gas is discharged toward the substrate W from the gas discharge port 531 of each gas discharge nozzle 532. The discharge trajectory of the nitrogen gas intersects with the discharge trajectory of the chemical liquid from the corresponding chemical liquid discharge port 521. That is, the liquid (chemical liquid) flow discharged from each chemical liquid discharge nozzle 522 is a gas (nitrogen gas) discharged from a gas discharge nozzle 532 provided so as to surround the chemical liquid discharge nozzle 522 corresponding to the chemical liquid discharge nozzle 522. ) Collide with the flow at the collision site G. The gas flow from each gas discharge port 531 is discharged so as to converge on the corresponding collision site G in the mixing region. This mixing region is an internal space at the tip of the nozzle body 51. For this reason, the chemical liquid is quickly made into droplets by the nitrogen gas from each gas discharge port 531 that collides with the chemical liquid in the immediate vicinity of the discharge direction of the chemical liquid from each chemical discharge port 521. As described above, the mixed region on the downstream side in the discharge direction of each chemical liquid discharge nozzle 522 and each gas discharge nozzle 532 is a liquid droplet generation unit 54 that generates liquid droplets, and the chemical liquid discharge nozzle 522 and the nozzle 522 Correspondingly, the gas discharge nozzles 532 are arranged in a row, so that a plurality of droplet generation units 54 are formed in a row. For this reason, a chemical liquid and nitrogen gas are discharged from each chemical liquid discharge nozzle 522 and each gas discharge nozzle 532, so that a strip-shaped droplet group can be generated. Thus, in this embodiment, the chemical liquid discharge nozzle 522 corresponds to the “liquid discharge means” of the present invention, and the gas discharge nozzle 532 corresponds to the “gas discharge means” of the present invention.

  Further, a blocking portion 55 corresponding to the “regulating means” of the present invention is provided at the nozzle tip portion so as to sandwich the strip droplet group from both sides along the arrangement direction R1 of the droplet generating portion 54. In addition, the other end of the blocking portion 55 that extends vertically, that is, the opening 511 provided at the tip of the nozzle opens in a slit shape toward the substrate W. For this reason, the droplets scattered from each of the plurality of droplet generation units 54 in a direction different from the arrangement direction R1 of the droplet generation units 54 are blocked by the blocking unit 55. For this reason, the width of the strip droplet group is regulated and uniformized in a direction R2 (second direction) substantially orthogonal to the arrangement direction D1 of the droplet generation unit 34. Also in this embodiment, the length of the blocking portion 55 in the direction orthogonal to the direction R1 and the direction R2, that is, the axial direction of the chemical liquid discharge nozzle 522, reliably regulates the width of the strip droplet group in the second direction. For this purpose, a sufficient length is taken and connected in the row direction. Therefore, even if the two-fluid nozzle having such a configuration is employed, the same effects as those of the previous embodiment can be obtained.

  Moreover, in the said embodiment, although the interruption | blocking parts 35 and 55 are each provided in the nozzle front-end | tip part as one component of the nozzle main bodies 31 and 51 as a control means, it is not limited to this. For example, the blocking portions 35 and 55 may be configured separately from the nozzle main bodies 31 and 51 and additionally attached to the nozzle tip.

  Further, in the above embodiment, by rotating the substrate W, the substrate W and the two-fluid nozzles 3 and (5) are relative to each other in a second direction different from the arrangement direction R1 (first direction) of the droplet generation units 34 and 54. Although it moves, it is not limited to this. For example, as shown in FIG. 6, the substrate W and the two-fluid nozzles 3 and (5) may be moved relative to each other in a predetermined direction to clean the substrate W. In FIG. 6, the two-fluid nozzles 3, (5) are fixed, and the substrate is placed in the longitudinal direction of the two-fluid nozzles 3, (5), that is, in the direction R2 substantially orthogonal to the arrangement direction R1 of the droplet generation units 34, 54. W is moved. For this reason, the width of the band-like droplet group discharged from the two-fluid nozzles 3 and (5) is regulated in the second direction and supplied to the substrate W. Therefore, the radiation range of the strip-shaped droplet group to the substrate W in the moving direction of the substrate W, that is, the cleaning direction of the substrate W is not unnecessarily widened, and particles are scattered on the substrate W due to the scattering of the droplets over a wide range. Reattachment can be prevented.

  In the above embodiment, the substrate W and the two-fluid nozzles 3 and 5 are relatively moved in the direction R2 substantially orthogonal to the arrangement direction R1 (first direction) of the droplet generation units 34 and 54. Without being limited, the relative movement direction (second direction) may be a direction different from the first direction.

  In the above embodiment, the plurality of droplet generation units 34 and 54 are arranged in a row on the nozzle bodies 31 and 51. However, the present invention is not limited to this, and the plurality of droplet generation units 34 and 54 have droplets. What is necessary is just to arrange | position so that supply to the board | substrate W may be continued in a strip | belt shape.

  In the above-described embodiment, the two-fluid nozzles 3 and 5 are arranged on the upper surface of the substrate W, and the band-like droplet group is supplied toward the upper surface of the substrate W to execute the cleaning of the substrate W. It is not limited. For example, the bottom surface of the substrate W may be cleaned by disposing the two-fluid nozzles 3 and 5 so as to face the lower surface of the substrate W and supplying a strip droplet group toward the lower surface of the substrate W.

  Further, in the above embodiment, each of the droplet generation units 34 and 54 receives the supply of the chemical solution and the nitrogen gas from the chemical solution supply pipes 32 and 52 and the gas supply pipes 33 and 53, respectively, and drops droplets under the same generation conditions. Although it is generated, it is not limited to this. For example, each of the droplet generation units 34 and 54 may be configured to be able to adjust the flow rate of the chemical solution and the flow rate / flow velocity of the nitrogen gas, or a part thereof. Thereby, a desired droplet diameter and droplet ejection speed can be obtained, and an optimum cleaning effect can be obtained according to the mode of cleaning. For example, when cleaning is performed by rotating the substrate W, the particle removal rate becomes smaller as the outer peripheral portion of the substrate W has a higher peripheral speed. Therefore, in order to make the removal rate comparable to the central portion of the substrate W, cleaning is performed. You need to lengthen the time. In this case, the removal rate in the radial direction of the substrate W can be made uniform by changing the droplet generation conditions in the droplet generation units 34 and 54 corresponding to the outer peripheral portion of the substrate W to increase the cleaning power. it can.

  In the above-described embodiment, for example, as shown in FIG. 3, the two-fluid nozzle 3 has an arrangement posture in which the chemical liquid (a group of liquid droplets) supplied toward the substrate W is substantially parallel to the normal direction of the substrate W. However, as shown in FIG. 7, the substrate W may be disposed so as to be inclined toward the upstream side in the relative movement direction.

  In the embodiment shown in FIG. 6, when the substrate W is fixed and the two-fluid nozzle 3 is moved in the direction R2, the two-fluid nozzle 3 is moved downstream in the moving direction, in other words, the unprocessed substrate W is not processed. You may arrange | position so that it may incline to the upstream which is an area | region. That is, since the chemical solution (band-shaped droplet group) is discharged to the upstream side of the substrate W with respect to the normal direction of the substrate W, the removed particles are mainly transported to the upstream side of the substrate W. The reattachment of particles to the downstream side of the substrate W can be reduced, and the particles existing on the upstream side of the substrate W are also removed again by the proceeding droplets.

  The present invention is applied to an apparatus for cleaning the surface of a general substrate including a semiconductor wafer, a glass substrate for a liquid crystal display device, a PDP (plasma display panel) substrate, or a glass substrate or a ceramic substrate for a magnetic disk. Can do.

1 is a schematic view showing a first embodiment of a substrate cleaning apparatus according to the present invention. It is a cross-sectional perspective view which shows the structure of the two-fluid nozzle used with the board | substrate cleaning apparatus of FIG. It is the figure which looked at the two-fluid nozzle used with the board | substrate washing | cleaning apparatus of FIG. 1 from the side. It is a figure which shows the structure of 2nd Embodiment of the board | substrate cleaning apparatus concerning this invention. It is a figure which shows the structure of the other 2 fluid nozzle of the board | substrate cleaning apparatus concerning this invention. It is a figure which shows other embodiment of the board | substrate cleaning apparatus concerning this invention. It is a figure which shows the modification of the two-fluid nozzle used with the board | substrate cleaning apparatus of FIG.

Explanation of symbols

3, 5 ... Two-fluid nozzle 4 ... Atmosphere blocker (atmosphere blocker)
14: Rotation drive mechanism (rotating means, relative moving means)
24 ... Chemical piping (liquid supply means)
25 ... Nitrogen gas piping (gas supply means)
34, 54 ... Droplet generating part 35, 55 ... Blocking part (regulating means)
522 ... Chemical liquid discharge nozzle (chemical liquid discharge means)
532 ... Gas discharge nozzle (gas discharge means)
Pa ... Rotation axis (center of rotation)
R1 ... first direction R2 ... second direction W ... substrate

Claims (9)

In a substrate cleaning apparatus for performing a cleaning process on the substrate by supplying liquid droplets generated by mixing liquid and gas to the surface of the substrate,
A plurality of droplet generation units that generate liquid droplets by mixing liquid and gas, and the plurality of droplet generation units are arranged in a row in the first direction to form the band-shaped droplet group A two-fluid nozzle that generates and supplies the strips to the substrate;
Liquid supply means for supplying the liquid to the plurality of droplet generation units;
A substrate cleaning apparatus, comprising: a gas supply unit configured to supply the gas to the plurality of droplet generation units. And further comprising relative movement means for relatively moving the substrate and the two-fluid nozzle in a second direction different from the first direction,
The substrate cleaning apparatus according to claim 1, wherein the two-fluid nozzle further includes a restricting unit that restricts a width of the strip droplet group in the second direction.   The restricting means restricts the width of the band-like droplet group in the second direction by blocking, in the second direction, droplets scattered in a direction different from the first direction from each of the plurality of droplet generating units. The substrate cleaning apparatus according to claim 2.   4. The substrate cleaning apparatus according to claim 1, further comprising an atmosphere blocking unit that is attached to the two-fluid nozzle and is spaced apart from the substrate while facing the substrate. 5. The relative movement means includes a rotation means for rotating the substrate,
5. The substrate cleaning apparatus according to claim 2, wherein a width of the strip-shaped droplet group in the first direction is at least larger than a distance from a rotation center of the substrate to an edge of the substrate.   The substrate cleaning apparatus according to claim 1, wherein the two-fluid nozzle is configured so that the droplet generation conditions can be changed for each droplet generation unit. The two-fluid nozzle includes a nozzle body having an opening at a tip portion thereof.
2. Each of the plurality of droplet generation units is disposed inside the nozzle body, and generates the strip droplet group by guiding the droplets generated in each droplet generation unit toward the opening. 7. The substrate cleaning apparatus according to any one of 6 to 6. The two-fluid nozzle includes a nozzle body having an opening at a tip portion thereof.
Each of the plurality of droplet generation units includes a liquid discharge unit that discharges liquid into the nozzle body, and a gas discharge unit that discharges gas in the vicinity of the liquid discharge unit. 7. The strip-shaped droplet group is generated by mixing the liquid discharged toward the opening and the gas discharged from the gas discharge unit to generate droplets. A substrate cleaning apparatus according to claim 1. The regulating means is disposed between the plurality of droplet generating units and the opening, and the strip-shaped liquid in the second direction until the generated strip-shaped droplet group is discharged from the opening. The substrate cleaning apparatus according to claim 7 or 8, wherein a droplet group width is regulated and supplied to the substrate.

Images