JP2009231618A - Development apparatus and development method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a development apparatus and a development method capable of suppressing a cost increase and preventing a development failure from occurring. <P>SOLUTION: At the periods of points in time t1-t4 in a solution layer formation process, a solution layer of a developer is formed on a substrate. Then, the rotational speed of the substrate is held at a low speed of 50 rpm temporarily, and then the rotation of the substrate is stopped. In this manner, by temporarily holding the rotational speed of the substrate W in an extremely low state before the rotation of the substrate stops, its state is maintained stably with the developer solution layer extended thinly on the substrate. At the same time, the rotation of the substrate can be stopped. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a developing device and a developing method for developing a substrate.

  Conventionally, a developing device is used for developing a resist film formed on a substrate. For example, a developing device includes a spin chuck that holds a substrate horizontally and rotates around a vertical axis, and a nozzle that supplies a developer to the substrate. During the development process, the nozzle moves from the outside of the substrate to above the center of the substrate while discharging the developer while the substrate is rotated by the spin chuck (see, for example, Patent Document 1).

In this case, the developer is supplied to the entire surface of the substrate, and a liquid layer of the developer is formed so as to cover the resist film on the substrate. In this state, the dissolution reaction of the resist film on the substrate proceeds. Thereafter, the developer and the dissolved resist film on the substrate are removed, and the development process is completed.
Japanese Patent Laid-Open No. 2005-210059

  When performing the development process as described above, if the resist film has high water repellency, the developer is repelled on the resist film. For this reason, it becomes difficult to form a liquid layer of the developer well. As a result, a desired portion of the resist film cannot be reliably dissolved, and development failure occurs.

  Note that a liquid layer can be formed by increasing the discharge flow rate of the formed developer, but the cost increases and development unevenness is likely to occur.

  An object of the present invention is to provide a developing device and a developing method capable of preventing the occurrence of development failure while suppressing an increase in cost.

  (1) A developing device according to a first aspect of the present invention is a rotation holding means for holding a substrate substantially horizontally and rotating it around an axis perpendicular to the substrate, and a developer liquid on the substrate rotated by the rotation holding means. A rotation layer holding unit that rotates the substrate at a first rotation speed when the liquid layer of the developer is formed by the liquid layer forming unit, and the substrate is formed after the liquid layer of the developer is formed. The rotational speed is gradually lowered from the first rotational speed.

  In this developing device, the substrate rotates while being held substantially horizontally by the rotation holding means. A liquid layer of the developer is formed on the substrate by the liquid layer forming means while the substrate is rotated at the first rotation speed. In this case, by forming the developer liquid layer while the substrate is rotated, the developer liquid layer can be thinly extended by centrifugal force.

  After the liquid layer of the developer is formed, the rotation speed of the substrate decreases stepwise from the first rotation speed. In this case, the rotation speed of the substrate can be lowered while stably maintaining the state in which the developer layer is thinly stretched on the substrate. When the rotation speed of the substrate is lowered, the amount of the developer that is shaken off by the centrifugal force is reduced, and the supply amount of the developer can be reduced or the supply of the developer can be stopped. As a result, it is possible to prevent development failure while suppressing an increase in cost.

  (2) The liquid layer forming means may continuously supply the developing solution from the central portion of the substrate to the peripheral portion, and then continuously supply the developing solution from the peripheral portion of the substrate to the central portion.

  In this case, the developer is continuously supplied from the center of the substrate to the peripheral portion, whereby the developer is supplied to the entire surface of the substrate, and the surface of the substrate is sufficiently wetted. Subsequently, the developer is continuously supplied from the peripheral portion to the central portion of the substrate by the developer supplying means, thereby forming a liquid layer of the developer on the substrate.

  As described above, by sufficiently moistening the surface of the substrate with the developer before forming the liquid layer of the developer, the developer is less likely to be repelled on the substrate even when the surface of the substrate has high water repellency. Thereby, the liquid layer of the developer can be reliably formed with a small amount of the developer. Therefore, it is possible to further suppress the increase in cost, and it is possible to more reliably prevent the development failure.

  Further, since the supply position of the developer moves between the central portion and the peripheral portion of the substrate, the reaction of the resist film is biased compared to the case where the developer is continuously supplied to a specific region on the substrate. Is prevented from proceeding. Thereby, development unevenness is suppressed and line width uniformity is improved.

  (3) The rotation holding means rotates the substrate at a second rotation speed higher than the first rotation speed during a period in which the developing solution is continuously supplied from the center portion to the peripheral edge portion of the substrate by the liquid layer forming means. The substrate may be rotated at the first rotation speed during a period in which the developer is continuously supplied from the peripheral edge portion to the central portion of the substrate by the liquid layer forming means.

  In this case, the surface of the substrate can be quickly wetted with the developing solution by continuously supplying the developing solution from the central portion to the peripheral portion of the substrate while the rotation speed of the substrate is relatively high. In addition, by supplying the developer continuously from the peripheral edge to the center of the substrate at a relatively low rotational speed of the substrate, the developer liquid layer can be reliably formed on the substrate in a state where the centrifugal force is small. Can be formed.

  (4) The rotation holding means has a fourth rotation speed higher than the first rotation speed from the third rotation speed lower than the first rotation speed before forming the liquid layer of the developer by the liquid layer forming means. The liquid layer forming means may supply the developing solution to the central portion of the substrate in a state where the substrate rotates at the third rotation speed.

  In this case, when the substrate rotates at the third rotation speed, a large centrifugal force does not act on the developer supplied on the substrate. Therefore, the developer is held in a region near the center of the substrate. When the rotation speed of the substrate increases from the third rotation speed to the fourth rotation speed, the developer held at the center of the substrate instantaneously spreads over the entire substrate by centrifugal force.

  As a result, the surface of the substrate can be wetted with the developer, and the liquid layer of the developer can be reliably formed with a small amount of developer. Therefore, it is possible to further suppress the increase in cost, and it is possible to more reliably prevent the development failure.

  (5) A developing method according to the second invention includes a step of rotating the substrate around an axis perpendicular to the substrate while holding the substrate substantially horizontal, and a liquid layer of the developer on the substrate rotating at the first rotational speed. And a step of lowering the rotation speed of the substrate stepwise from the first rotation speed after forming the liquid layer of the developer.

  In this developing method, the liquid layer of the developer is formed on the substrate while the substrate is rotated substantially at the first rotation speed while being held substantially horizontally. In this case, by forming the developer liquid layer while the substrate is rotated, the developer liquid layer can be thinly extended by centrifugal force.

  After the liquid layer of the developer is formed, the rotation speed of the substrate decreases stepwise from the first rotation speed. In this case, the rotation speed of the substrate can be lowered while stably maintaining the state in which the developer layer is thinly stretched on the substrate. When the rotation speed of the substrate is lowered, the amount of the developer that is shaken off by the centrifugal force is reduced, and the supply amount of the developer can be reduced or the supply of the developer can be stopped. As a result, it is possible to prevent development failure while suppressing an increase in cost.

  According to the present invention, the rotational speed of the substrate can be lowered while stably maintaining the state in which the developer layer is thinly stretched on the substrate. Thereby, the occurrence of development failure can be prevented, the amount of the developer used can be reduced, and the increase in cost can be suppressed.

  Hereinafter, a developing device and a developing method according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the substrate refers to a semiconductor substrate, a liquid crystal display substrate, a plasma display substrate, a photomask glass substrate, an optical disk substrate, a magnetic disk substrate, a magneto-optical disk substrate, a photomask substrate, and the like. Say.

(1) Configuration of Developing Device FIG. 1 is a plan view showing the configuration of the developing device, and FIG. 2 is a cross-sectional view taken along the line QQ of the developing device in FIG.

  As shown in FIGS. 1 and 2, the developing device 100 includes a spin chuck 10 that sucks and holds the substrate W in a horizontal posture. The spin chuck 10 is fixed to the distal end portion of the rotating shaft 12 of the motor 11 (FIG. 2), and is configured to be rotatable around a vertical axis. A circular inner cup 13 is provided around the spin chuck 10 so as to be movable up and down so as to surround the substrate W. A square outer cup 14 is provided around the inner cup 13.

  As shown in FIG. 1, a standby pod 15 is provided on the side of the outer cup 14. A guide rail 16 is provided so as to extend in parallel with the outer cup 14 and the standby pod 15. An arm drive unit 17 is provided so as to be movable along the guide rail 16. A nozzle arm 18 that extends in a direction perpendicular to the guide rail 16 in the horizontal plane is attached to the arm drive unit 17. The nozzle arm 18 is driven by the arm drive unit 17 and moves in the direction along the guide rail 16 and moves up and down in the vertical direction.

  A rinsing liquid discharge nozzle 19 that discharges pure water as a rinsing liquid for cleaning is provided in a region opposite to the guide rail 16 with respect to the spin chuck 10 so as to be rotatable in the direction of the arrow R1.

  As shown in FIG. 2, a developer nozzle 21 having a plurality (five in this example) of developer discharge ports 22 is provided at the tip of the nozzle arm 18. At the time of developing the substrate W, the nozzle arm 18 is driven to move the developer nozzle 21 from the standby pod 15 to above the substrate W.

  The developer nozzle 21 is connected to a developer supply source G1 through a supply pipe 31. A valve V <b> 1 is inserted in the supply pipe 31. By opening the valve V1, the developer is supplied from the developer supply source G1 to the developer nozzle 21.

  The rinsing liquid discharge nozzle 19 is connected to the rinsing liquid supply source G <b> 2 via the supply pipe 35. A valve V2 is interposed in the supply pipe 35. By opening the valve V2, the rinse liquid is supplied from the rinse liquid supply source G2 to the rinse liquid discharge nozzle 19.

  FIG. 3 is a schematic perspective view of the developer nozzle 21. As shown in FIG. 3, the developer nozzle 21 is provided with five developer discharge ports 22 directed vertically downward along the width direction (direction parallel to the guide rail 16 in FIG. 1) at equal intervals. ing. The developer supplied to the developer nozzle 21 is discharged from the developer discharge port 22. Each developer discharge port 22 is disposed so as to pass above the central portion of the substrate W held by the spin chuck 10 as the developer nozzle 21 moves.

  FIG. 4 is a block diagram illustrating a control system of the developing device 100. As shown in FIG. 4, the developing device 100 includes a control unit 50. The operations of the spin chuck 10, the motor 11, the arm drive unit 17, the rinse liquid discharge nozzle 19, and the valves V <b> 1 and V <b> 2 are controlled by the control unit 50.

(2) Operation of Developing Device Next, the operation of the developing device 100 will be described. FIG. 5 is a timing chart showing changes in the rotation speed of the substrate W, the flow rate of the developing solution, and the flow rate of the rinsing liquid during the developing process of the substrate W. In the present embodiment, the development process is divided into a liquid layer formation process, a development process, and a cleaning process. Note that the development processing described below is performed after the resist film formed on the substrate W is subjected to exposure processing.

  As shown in FIG. 5, the rotation of the substrate W is started by the spin chuck 10 at the time t <b> 1 of the liquid layer forming process. At the subsequent time t2, discharge of the developer from the developer nozzle 21 is started. In the period from time t1 to time t3, the rotation speed of the substrate W is maintained at, for example, 1000 rpm.

  At time t3, the rotation speed of the substrate W decreases to, for example, 200 rpm, and at time t4, the rotation speed of the substrate W decreases, for example, to 50 rpm. At time t5, the rotation of the substrate W is stopped. At time t6, the discharge of the developer from the developer nozzle 21 is stopped. In the period from time t2 to time t6, the developer nozzle 21 moves between the upper part of the center of the substrate W and the upper part of the peripheral edge while discharging the developer. The discharge flow rate of the developer is maintained at 400 ml / min, for example.

  In this liquid layer forming step, a liquid layer of a developer is formed so as to cover the resist film on the substrate W. Details of the liquid layer forming step will be described later.

  During the period from time t6 to time t7 of the development process, the discharge of the developer and the rotation of the substrate W are maintained in a stopped state. During this period, the dissolution reaction of the portion excluding the pattern portion of the resist film proceeds by the developer held on the substrate W.

  During the period from the time t7 to t8 of the cleaning process, the spin chuck 10 rotates the substrate W at, for example, 700 rpm, and the rinse liquid is discharged from the rinse liquid discharge nozzle 19 onto the substrate W. Thereby, the developer and the dissolved resist on the substrate W are washed away. Subsequently, the substrate W rotates at a high speed of, for example, 2000 rpm during a period from time t8 to time t9. The rinsing liquid adhering to the substrate W is shaken off by the centrifugal force accompanying the rotation, and the substrate W is dried. Thereby, the development processing of the substrate W is completed.

(3) Liquid Layer Forming Step Next, details of the operation of the developing device 100 in the liquid layer forming step will be described with reference to FIGS. 5 and 6. FIG. 6 is a schematic plan view and a side view for explaining the operation of the developing device 100 in the liquid layer forming step.

  At time t2 in FIG. 5, the discharge of the developer starts in a state where the developer nozzle 21 is located above the central portion of the substrate W as shown in FIGS. 6 (a) and 6 (b). Then, during the period from the time point t2 to the time point t3 in FIG. 5, as shown in FIG. 6C and FIG. Move to the top of the section. As a result, the developer is supplied to the entire surface of the substrate W.

  In the period from time t3 to time t4 in FIG. 5, the rotation speed of the substrate W decreases, and as shown in FIGS. 6E and 6F, the developer nozzle 21 discharges the developer and the substrate. It moves from above the periphery of W to above the center. In this case, the amount of the developer that is shaken off to the outside of the substrate W is reduced, and the supplied developer is held on the substrate W. Thereby, a liquid layer of the developer is formed on the substrate W.

  Here, during the period from the time point t2 to the time point t4, the developer nozzle 21 moves so that the developer discharge port 22 does not protrude outward from the region above the substrate W. In this case, the developer is not supplied so as to cross the outer peripheral end of the substrate W. Thereby, scattering of the developer can be suppressed. Therefore, it is possible to prevent the developer from adhering to each part in the developing device 100.

  For example, when the diameter of the substrate W is 300 mm, the developer nozzle 21 moves from above the central portion of the substrate W to above the peripheral portion in 1 to 3 seconds, for example, above the peripheral portion of the substrate W. For example, from 1 to 5 seconds above the center.

  The moving speed of the developer nozzle 21 may be constant, or may change according to the moving direction or position. For example, the moving speed of the developing solution nozzle 21 near the upper part of the peripheral edge of the substrate W may be lower than the moving speed of the developing solution nozzle 21 near the upper part of the central portion of the substrate W. In this case, the developer can be sufficiently supplied also to the peripheral area of the substrate W having a large area.

  FIG. 7 is a perspective view and a side view showing the process of forming a developer liquid layer. As shown in FIGS. 7A and 7B, the developing solution nozzle 21 discharges the developing solution while the substrate W rotates, and from above the peripheral portion of the substrate W to above the central portion of the substrate W. By moving toward the center, the developer is supplied spirally from the peripheral edge of the substrate W toward the center. As a result, a liquid layer of the developer is formed from the peripheral edge of the substrate W toward the center.

  In this case, by forming the developer liquid layer while the substrate W is rotated, the developer liquid layer can be thinly extended by centrifugal force. Therefore, the amount of the developer used can be suppressed as compared with the case where the developer layer is formed with the substrate W fixed.

  After the liquid layer of the developer is formed on the substrate W, the rotation speed of the substrate W decreases to 50 rpm at time t4 in FIG. Then, the rotation of the substrate W is stopped at time t5 in FIG. 5, and the discharge of the developer from the developer nozzle 21 is stopped at time t6.

  In the present embodiment, after forming the liquid layer of the developer, the rotation speed of the substrate W is temporarily held at a low speed of 50 rpm, and then the rotation of the substrate W is stopped. Thus, by temporarily holding the rotation speed of the substrate W in a very low state before the rotation of the substrate W is stopped, the state in which the liquid layer of the developer is thinly stretched on the substrate W can be stabilized. The rotation of the substrate W can be stopped while maintaining it. Thereby, the development of the resist film can be reliably advanced in a state where the supply of the developing solution to the substrate W is stopped. Therefore, it is possible to reduce the usage amount of the developing solution and reduce the cost, and it is possible to reliably prevent development failure.

  In the present embodiment, the developer is supplied to the entire surface of the substrate W during the period from time t2 to time t3 before the liquid layer is formed. Thereby, the entire surface of the substrate W becomes wet with the developer, and the wettability of the surface of the substrate W is improved. Therefore, even when the surface of the substrate W (resist film surface) has high water repellency, the developer is less likely to be repelled on the substrate W. Thereby, a liquid layer can be reliably formed with a small amount of developer. Therefore, it is possible to further reduce the cost and more reliably prevent the development failure.

  Further, by supplying the developer to the substrate W while the developer nozzle 21 moves, it is possible to prevent the reaction of the resist film from proceeding unevenly in a specific region on the substrate W. Thereby, development unevenness is suppressed and CD (line width) uniformity is improved.

  Note that the rotation speed of the substrate W and the flow rate of the developer are not limited to the above example, and may be appropriately changed according to various conditions such as the size of the substrate W or water repellency.

  For example, it is preferable to adjust the rotation speed of the substrate W in the range of 500 rpm to 2000 rpm in the period from time t1 to time t3. The rotation speed of the substrate W in the period from the time point t1 to t3 corresponds to the second or fourth rotation speed in the claims. If the rotation speed of the substrate W is too high, most of the developer supplied to the substrate W is shaken off by the centrifugal force, and the surface of the substrate W cannot be sufficiently wetted with the developer. On the other hand, if the rotation speed of the substrate W is too low, the developer cannot be spread on the substrate W appropriately.

  In the period from time t3 to time t4, it is preferable to adjust the rotation speed of the substrate W in a range of 100 rpm to 500 rpm. The rotation speed of the substrate W in the period from the time point t3 to t4 corresponds to the first rotation speed in the claims. If the rotation speed of the substrate W is too high, the developer cannot be held on the substrate W. On the other hand, if the rotation speed of the substrate W is too low, the time efficiency deteriorates.

  In the period from time t4 to time t5, it is preferable to adjust the rotation speed of the substrate W in the range of 10 rpm to 100 rpm. If the rotation speed of the substrate W is too high, the rotation of the substrate W cannot be stopped while the developer layer is stably held on the substrate W. On the other hand, if the rotation speed of the substrate W is too low, the developer layer cannot be maintained in a thinly stretched state, and the developer may collect in a partial region on the substrate W due to surface tension. .

  The flow rate of the developer is preferably adjusted in the range of 300 ml / min to 600 ml / min. Further, the flow rate of the developer may be changed according to the moving direction or position of the developer nozzle 21.

  In the above-described embodiment, the rotational speed of the substrate W is decreased from 50 rpm to 0 rpm at time t5. However, the substrate W after time t5 depends on the film quality and the like of the resist film formed on the substrate W. May be once increased in the range of 50 to 200 rpm and then decreased to 0 rpm.

(4) Other Operation Example in Liquid Layer Formation Step Next, another operation example of the developing device 100 in the liquid layer formation step will be described. FIG. 8 is a timing chart showing changes in the rotation speed of the substrate W, the flow rate of the developing solution, and the flow rate of the rinsing liquid in the liquid layer forming step of this example.

  This example differs from the example shown in FIG. 5 in the following points. As shown in FIG. 8, in this example, first, at time t <b> 11, the substrate W starts rotating at a low speed of 20 rpm, and the developer nozzle 21 starts to discharge the developer above the central portion of the substrate W. Thereafter, the rotation speed of the substrate W increases to 1000 rpm, and the developer nozzle 21 starts moving while discharging the developer. Then, the same operation as in the above example is performed. The rotation speed of the substrate W in the period from the time point t11 to t1 corresponds to the third rotation speed in the claims.

  FIG. 9 is a plan view and a side view showing the state of the developer supplied on the substrate W. FIG. In the period from time t11 to time t1 in FIG. 8, the rotational speed of the substrate W is low, so that centrifugal force does not act on the developer supplied to the substrate W. For this reason, as shown in FIGS. 9A and 9B, the developer supplied to the central portion of the substrate W does not spread to the peripheral portion of the substrate W, and is within a substantially constant region due to surface tension. Held in.

  When the rotation speed of the substrate W increases at the time point t1 in FIG. 8, the developer held on the central portion of the substrate W is applied to the substrate W by centrifugal force as shown in FIGS. 9 (c) and 9 (d). It spreads instantaneously to the whole.

  As described above, since the developer can be spread on the entire surface of the substrate W in advance at the time t1, the entire surface of the substrate W can be wetted with the developer efficiently and reliably. Therefore, the liquid layer can be more reliably formed with a small amount of developer.

  In this example, the developer is continuously discharged during the period from time t11 to time t6. However, the discharge of the developer may be temporarily stopped after a predetermined amount of developer is discharged from time t11.

(5) Still another example of operation In the above example, the developer nozzle 21 moves between the upper portion of the substrate W and the upper peripheral portion while discharging the developer in the liquid layer forming step. However, the developer nozzle 21 may discharge the developer continuously above the central portion of the substrate W.

  In the development process, the rotation of the substrate W may be maintained at a low speed of, for example, less than 200 rpm without stopping the rotation of the substrate W. Even in this case, the state in which the developer layer is thinly extended on the substrate W can be stably maintained by lowering the rotation speed of the substrate W stepwise.

(6) Correspondence between each constituent element of claim and each element of the embodiment Hereinafter, an example of correspondence between each constituent element of the claim and each element of the embodiment will be described. It is not limited to.

  In the above embodiment, the spin chuck 10 and the motor 11 are examples of rotation holding means, and the developer nozzle 21 is an example of developer supply means.

  As each constituent element in the claims, various other elements having configurations or functions described in the claims can be used.

  The present invention can be effectively used for processing various substrates.

It is a top view which shows the structure of a developing device. FIG. 2 is a cross-sectional view taken along line QQ of the developing device in FIG. 1. It is a schematic perspective view of a developing solution nozzle. It is a block diagram which shows the control system of a developing device. FIG. 10 is a timing chart showing changes in the rotation speed of the substrate, the flow rate of the developing solution, and the flow rate of the rinsing liquid during the substrate development process. It is the typical top view and side view for demonstrating operation | movement of the image development apparatus in a liquid layer formation process. It is the perspective view and side view which show the formation process of the liquid layer of a developing solution. It is a timing diagram which shows the change of the rotational speed of the board | substrate in the other example of a liquid layer formation process, the flow volume of a developing solution, and the flow volume of a rinse liquid. It is the top view and side view which show the state of the developing solution supplied on the board | substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Spin chuck 11 Motor 16 Guide rail 17 Arm drive part 18 Nozzle arm 19 Rinse liquid discharge nozzle 21 Developer liquid nozzle 22 Developer discharge port 100 Developing device W Substrate

Claims (5)

Rotation holding means for rotating around an axis perpendicular to the substrate while holding the substrate substantially horizontally;
A liquid layer forming means for forming a liquid layer of the developer on the substrate rotated by the rotation holding means,
The rotation holding unit rotates the substrate at a first rotation speed when the liquid layer of the developer is formed by the liquid layer forming unit, and the rotation speed of the substrate is changed to the first rotation speed after the formation of the liquid layer of the developer. The developing device is lowered step by step. 2. The liquid layer forming means, wherein after the developer is continuously supplied from the central portion of the substrate to the peripheral portion, the developer is continuously supplied from the peripheral portion of the substrate to the central portion. Development device. The rotation holding unit rotates the substrate at a second rotation speed higher than the first rotation speed during a period in which the developing solution is continuously supplied from the central portion to the peripheral portion of the substrate by the liquid layer forming unit. 3. The developing device according to claim 2, wherein the substrate is rotated at the first rotation speed during a period in which the developer is continuously supplied from the peripheral portion to the central portion of the substrate by the liquid layer forming means. The rotation holding unit is configured to rotate the substrate from a third rotation speed lower than the first rotation speed to a fourth rotation speed equal to or higher than the first rotation speed before forming the developer liquid layer by the liquid layer forming means. Rise to
The developing device according to claim 1, wherein the liquid layer forming unit supplies a developing solution to a central portion of the substrate in a state where the substrate rotates at the third rotation speed. Rotating around an axis perpendicular to the substrate while holding the substrate substantially horizontal;
Forming a developer layer on a substrate rotating at a first rotational speed;
And a step of lowering the rotation speed of the substrate stepwise from the first rotation speed after forming the liquid layer of the developer.

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