JP6538239B2 - Substrate processing method, substrate processing apparatus and recording medium - Google Patents

Description

  The present disclosure relates to a substrate processing method, a substrate processing apparatus, and a recording medium.

  Patent Document 1 discloses a developing method using a nozzle having a discharge port for a developing solution and a liquid contact surface formed around the discharge port. In this developing method, the developer is supplied from the discharge port to the surface of the substrate and the liquid contact surface is brought into contact with the developer while the substrate is rotated and the nozzle is disposed so that the liquid contact surface faces the surface of the substrate. A step of forming a liquid film of the developer on the substrate by moving the nozzle while making the process include.

JP, 2015-53467, A

  An object of the present disclosure is to provide a method, an apparatus, and a recording medium that can more reliably suppress the amount of progress of development depending on the position on the substrate.

  In the substrate processing method according to the present disclosure, the substrate is rotated at the first number of rotations, and the wetted surface formed around the discharge port of the nozzle is opposed to the surface of the substrate. A liquid film of the developer was formed on the surface of the substrate by supplying the developer and moving the nozzle while bringing the liquid contact surface into contact with the developer, and a liquid film was formed on the surface of the substrate After the substrate is rotated at a second rotation number lower than the first rotation number after the supply of the developer from the discharge port is stopped, and after the substrate is rotated at a second rotation number, the first rotation is performed. The liquid film on the surface of the substrate is obtained by rotating the substrate at a third rotation number higher than the number and rotating the substrate at a third rotation number and then setting the rotation number of the substrate equal to or less than the second rotation number. And holding.

  According to this substrate processing method, in the process of forming the liquid film, the liquid contact surface of the nozzle contacts the developer supplied from the discharge port of the nozzle to the surface of the substrate. The relative motion between the wetted surface and the surface of the substrate causes the developer to be agitated therebetween. For this reason, the uniformity of the progress rate of development between the liquid contact surface and the surface of the substrate is enhanced.

  After the liquid film is formed, the number of rotations of the substrate is reduced from the first number of rotations to the second number of rotations, and then raised to a third number of rotations higher than the first number of rotations. As the number of rotations of the substrate drops from the first number of rotations to the second number of rotations, the developing solution moves closer to the rotation center of the substrate, and the number of rotations of the substrate increases from the second number of rotations to the third number of rotations. The liquid spreads on the outer peripheral side of the substrate. By moving to the rotation center side of the substrate before spreading to the outer peripheral side of the substrate, the kinetic energy of the developer when spreading to the outer peripheral side of the substrate increases, so the developer on the rotation center side of the substrate is more reliably It spreads around the outer periphery of the substrate. Thereby, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be enhanced. For this reason, even after the formation of the liquid film, the uniformity of the development progress speed is enhanced.

  As described above, the uniformity of the development progress rate is enhanced both in the formation process of the liquid film and after the formation of the liquid film, so that it is possible to more reliably suppress the progress amount of development depending on the position on the substrate.

  When the liquid film is formed on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developing solution, the nozzle may be moved from the outer peripheral side of the substrate to the rotation center side. In this case, the supply of the developing solution on the rotation center side of the substrate is performed later than the supply of the developing solution on the outer peripheral side of the substrate, so immediately after the formation of the liquid film, the developing solution approaches the rotation center side of the substrate. The freshness of the Therefore, when the substrate is rotated at the third rotation number, the developer on the outer peripheral side with low freshness is replaced by the developer on the rotation center side with high freshness. Since the uniformity of the concentration of the developer tends to increase as the freshness of the developer increases, the developer in the liquid film is replaced by replacing the developer with a low degree of freshness with the developer with a high degree of freshness. The uniformity of the concentration is further enhanced. This makes it possible to further improve the uniformity of the development speed.

  The method may further include, after forming the liquid film on the surface of the substrate, separating the liquid contact surface from the surface of the substrate before the rotation of the substrate at the second rotation number is completed. In this case, the developing solution in the liquid film can be more reliably rotated on the side of the rotation center of the substrate by expanding the area between the liquid contact surface and the surface of the substrate before the rotation of the substrate at the second rotation number is completed Can be Therefore, when the substrate is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be further enhanced.

  The separation of the liquid contact surface from the surface of the substrate at a first speed is the separation of the liquid contact surface from the surface of the substrate to a first distance, and the separation of the liquid contact surface from the surface of the substrate to a first distance After holding the state, the liquid contact surface may be further separated at a second velocity lower than the first velocity. In this case, after the wetted surface is separated from the surface of the substrate to the first distance at a first velocity, the distance between the wetted surface and the surface of the substrate is maintained to allow the wetted surface and the liquid film to be separated. The contact surface is reduced. Thereafter, by further separating the liquid contact surface at a second speed lower than the first speed, the peeling of the developer when the liquid contact surface is separated from the liquid film is suppressed. From these facts, when the liquid contact surface is separated from the liquid film, the developer hardly remains on the liquid contact surface, so that the occurrence of liquid dripping from the liquid contact surface separated from the liquid film is suppressed. Therefore, when the substrate is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be further enhanced.

  The first distance may be a distance at which a liquid column is formed between the liquid film of the developer and the liquid contact surface. In this case, in the process of separating the liquid contact surface from the surface of the substrate to the first distance, the contact surface between the liquid contact surface and the liquid film is more reliably reduced in a state in which the developing solution is prevented from being broken. Therefore, when the liquid contact surface is separated from the liquid film, the developer can be more reliably prevented from remaining on the liquid contact surface.

  When the liquid film is formed on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developer, the moving speed of the nozzle may be changed midway. In this case, by changing the moving speed of the nozzle, the amount of the developer on the rotation center side of the liquid film can be more properly optimized. Therefore, when the substrate is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved. The "amount of developer" in the liquid film means the amount of developer per unit area of the liquid film. The same applies to the following.

  By moving the nozzle while bringing the liquid-contacted surface into contact with the developer, when the liquid film is formed on the surface of the substrate, the moving speed of the nozzle is reduced according to the discharge port approaching the rotation center of the substrate. May be In this case, immediately after the formation of the liquid film, the amount of the developer on the rotation center side of the liquid film is larger than the amount of the developer on the outer peripheral side of the liquid film. Therefore, when the substrate is rotated at the third rotation number, the developer on the rotation center side of the substrate is more reliably spread to the outer peripheral side of the substrate, so that the thickness of the liquid film and the concentration of the developer in the liquid film Uniformity can be more reliably improved.

  When the liquid film is formed on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developer, the discharge amount of the developer from the discharge port may be changed halfway. In this case, by changing the discharge amount of the developer from the discharge port, the amount of the developer on the rotation center side of the liquid film can be more properly optimized. Therefore, when the substrate is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved.

  When the liquid film is formed on the surface of the substrate by moving the nozzle while the liquid contact surface is in contact with the developing solution, the discharging port approaches the rotation center of the substrate and the developing solution from the discharging port is moved. The discharge amount may be increased. In this case, immediately after the formation of the liquid film, the amount of the developer on the rotation center side of the liquid film is larger than the amount of the developer on the outer peripheral side of the liquid film. Therefore, when the substrate is rotated at the third rotation number, the developer on the rotation center side of the substrate is more reliably spread to the outer peripheral side of the substrate, so that the thickness of the liquid film and the concentration of the developer in the liquid film Uniformity can be more reliably improved.

  When the liquid film is formed on the surface of the substrate by moving the nozzle while the liquid contact surface is in contact with the developing solution, the nozzle may be moved with the position where the discharge port deviates from the rotation center of the substrate as the end point. . In this case, the amount of developer on the side of the rotation center of the liquid film can be adjusted by the position at which the movement of the nozzle is stopped. For example, by stopping the movement of the nozzle before the discharge port reaches the rotation center of the substrate, the amount of the developer on the rotation center side of the liquid film can be reduced. On the other hand, by moving the nozzle until the discharge port passes the rotation center of the substrate, the amount of developer on the rotation center side of the liquid film can be increased. Therefore, the amount of the developer on the side of the rotation center of the liquid film can be more properly optimized by the position at which the movement of the nozzle is stopped. Therefore, when the substrate is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved.

  By moving the nozzle while bringing the liquid contact surface into contact with the developing solution, when forming a liquid film on the surface of the substrate, the discharge port deviates from the rotation center of the substrate and the rotation center of the substrate passes through the liquid contact surface. The nozzle may be moved with the position as an end point. In this case, even in the case where the movement of the nozzle is stopped at a position where the discharge port deviates from the rotation center of the substrate, the range in which the liquid contact surface of the nozzle faces extends over the entire surface of the substrate. Therefore, the developer can be applied more reliably to the rotation center of the substrate. Therefore, when the substrate is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved.

  When the liquid film is formed on the surface of the substrate by moving the nozzle while the liquid contact surface is in contact with the developing solution, the nozzle may be moved until the discharge port passes the rotation center of the substrate. In this case, immediately after the formation of the liquid film, the amount of the developer on the rotation center side of the liquid film is larger than the amount of the developer on the outer peripheral side of the liquid film. Therefore, when the substrate is rotated at the third rotation number, the developer on the rotation center side of the substrate is more reliably spread to the outer peripheral side of the substrate, so that the thickness of the liquid film and the concentration of the developer in the liquid film Uniformity can be more reliably improved.

  A substrate processing apparatus according to the present disclosure transports a nozzle including a rotation holding unit that holds and rotates a substrate, a discharge port for a developing solution, a wetted surface formed around the discharge port, and a nozzle. And a controller for controlling the rotation holding unit to rotate the substrate at the first number of rotations. The developer is supplied from the discharge port to the surface of the substrate in a state in which the liquid contact surface is opposed to the surface of the substrate, and the nozzle is moved while the liquid contact surface is in contact with the developer, whereby the substrate is on the surface. The first rotation is performed in a state where the supply of the developer from the discharge port is stopped after the developer supply portion is controlled to form a liquid film of the developer and the liquid film is formed on the surface of the substrate. The rotation holder is set to rotate the substrate at a second rotation speed lower than the number Controlling the rotation holding unit so as to rotate the substrate at a third rotation number higher than the first rotation number after rotating the substrate at the second rotation number, and controlling the substrate at the third rotation number Controlling the rotation holding unit to hold the liquid film on the surface of the substrate by setting the number of rotations of the substrate to be equal to or lower than the second number of rotations after rotating There is.

  A recording medium according to the present disclosure is a computer-readable recording medium in which a program for causing a substrate processing apparatus to execute the substrate processing method is recorded.

  According to the present disclosure, it can be more reliably suppressed that the amount of progress of development varies depending on the position on the substrate.

It is a perspective view which shows schematic structure of a substrate processing system. It is sectional drawing which follows the II-II line in FIG. It is sectional drawing which follows the III-III line in FIG. It is a schematic diagram which shows schematic structure of the image development unit. It is a perspective view which shows an example of a nozzle. 5 is a flowchart of a development processing procedure. It is a schematic diagram which shows the state of the board | substrate in formation of a liquid film. It is a schematic diagram which shows the state of the board | substrate in formation of a liquid film. It is a schematic diagram which shows the state of the board | substrate in adjustment of liquid concentration. It is a schematic diagram which shows the state of the nozzle at the time of separating from a liquid film. It is a schematic diagram which shows the state of the board | substrate in supply of a rinse agent.

  Hereinafter, embodiments will be described in detail with reference to the drawings. In the description, the same elements or elements having the same function are denoted by the same reference numerals, and redundant description will be omitted.

[Substrate processing system]
The substrate processing system 1 is a system for forming a photosensitive film, exposing the photosensitive film, and developing the photosensitive film on a substrate. The substrate to be processed is, for example, a semiconductor wafer W. The photosensitive film is, for example, a resist film. The substrate processing system 1 includes a coating / developing device 2 and an exposure device 3. The exposure apparatus 3 performs exposure processing of a resist film (photosensitive film) formed on a wafer W (substrate). Specifically, energy rays are irradiated to the exposure target portion of the resist film by a method such as immersion exposure. The coating / developing device 2 performs processing for forming a resist film on the surface of the wafer W (substrate) before exposure processing by the exposure device 3 and performs development processing for the resist film after exposure processing.

[Substrate processing apparatus]
Hereinafter, the configuration of the coating and developing apparatus 2 will be described as an example of the substrate processing apparatus. As shown in FIGS. 1 to 3, the coating and developing apparatus 2 includes a carrier block 4, a processing block 5, an interface block 6, and a controller 100.

  The carrier block 4 performs the introduction of the wafer W into the coating and developing apparatus 2 and the drawing of the wafer W from the coating and developing apparatus 2. For example, the carrier block 4 can support a plurality of carriers 11 for the wafer W, and incorporates the delivery arm A1. The carrier 11 accommodates, for example, a plurality of circular wafers W. The delivery arm A1 takes out the wafer W from the carrier 11 and delivers it to the processing block 5, receives the wafer W from the processing block 5, and returns the wafer W into the carrier 11.

  The processing block 5 has a plurality of processing modules 14, 15, 16, 17. As shown in FIGS. 2 and 3, the processing modules 14, 15, 16 and 17 include a plurality of liquid processing units U1, a plurality of heat processing units U2, and a transfer arm A3 for transferring the wafer W to these units. It has built-in. The processing module 17 further incorporates a direct transfer arm A6 that transfers the wafer W without passing through the liquid processing unit U1 and the thermal processing unit U2. The liquid processing unit U1 applies the processing liquid to the surface of the wafer W. The thermal processing unit U2 incorporates, for example, a heating plate and a cooling plate, heats the wafer W by the heating plate, cools the heated wafer W by the cooling plate, and performs heat treatment.

  The processing module 14 forms an underlayer film on the surface of the wafer W by the liquid processing unit U1 and the thermal processing unit U2. The liquid processing unit U1 of the processing module 14 applies the processing liquid for forming the lower layer film on the wafer W. The heat treatment unit U2 of the processing module 14 performs various heat treatments associated with the formation of the lower layer film.

  The processing module 15 forms a resist film on the lower layer film by the liquid processing unit U1 and the heat processing unit U2. The liquid processing unit U1 of the processing module 15 applies the processing liquid for resist film formation on the lower layer film. The thermal processing unit U2 of the processing module 15 performs various thermal processing associated with the formation of the resist film.

  The processing module 16 forms an upper film on the resist film by the liquid processing unit U1 and the heat processing unit U2. The liquid processing unit U1 of the processing module 16 applies a liquid for forming the upper layer film on the resist film. The heat treatment unit U2 of the processing module 16 performs various heat treatments associated with the formation of the upper layer film.

  The processing module 17 performs development processing of the exposed resist film by the liquid processing unit U1 and the heat processing unit U2. The liquid processing unit U1 of the processing module 17 applies a developing solution on the surface of the exposed wafer W, and then rinses the developing solution with a rinse liquid to perform a developing process on the resist film. The heat treatment unit U2 of the processing module 17 performs various heat treatments associated with the development process. Specific examples of the heat treatment include heat treatment (PEB: Post Exposure Bake) before development treatment, heat treatment (PB: Post Bake) after development treatment, and the like.

  A shelf unit U10 is provided on the side of the carrier block 4 in the processing block 5. The shelf unit U10 is divided into a plurality of cells lined up in the vertical direction. A lift arm A7 is provided in the vicinity of the shelf unit U10. The lift arm A7 lifts and lowers the wafer W between the cells of the shelf unit U10.

  A shelf unit U11 is provided on the interface block 6 side in the processing block 5. The shelf unit U11 is divided into a plurality of cells lined up in the vertical direction.

  The interface block 6 exchanges the wafer W with the exposure apparatus 3. For example, the interface block 6 incorporates the delivery arm A 8 and is connected to the exposure apparatus 3. The delivery arm A8 delivers the wafer W disposed in the shelf unit U11 to the exposure device 3, receives the wafer W from the exposure device 3, and returns the wafer W to the shelf unit U11.

  The controller 100 controls the coating / developing device 2 to execute the coating / developing process in the following procedure, for example. First, the controller 100 controls the transfer arm A1 to transfer the wafer W in the carrier 11 to the shelf unit U10, and controls the lift arm A7 to place the wafer W in the cell for the processing module 14.

  Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U10 to the liquid processing unit U1 and the heat treatment unit U2 in the processing module 14, and forms an underlayer film on the surface of the wafer W. Thus, the liquid processing unit U1 and the heat processing unit U2 are controlled. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W on which the lower layer film is formed to the shelf unit U10, and controls the lift arm A7 to place the wafer W in the cell for the processing module 15.

  Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U10 to the liquid processing unit U1 and the thermal processing unit U2 in the processing module 15, and forms a resist film on the lower layer film of the wafer W The liquid processing unit U1 and the heat processing unit U2 are controlled as follows. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W to the shelf unit U10, and controls the lift arm A7 to place the wafer W in the cell for the processing module 16.

  Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U10 to each unit in the processing module 16, and forms the upper layer film on the resist film of the wafer W. Control U1 and heat treatment unit U2. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W to the shelf unit U10, and controls the lift arm A7 to place the wafer W in the cell for the processing module 17.

  Next, the controller 100 directly controls the transfer arm A6 so as to transfer the wafer W of the shelf unit U10 to the shelf unit U11, and controls the delivery arm A8 so as to send out the wafer W to the exposure apparatus 3. Thereafter, the controller 100 controls the transfer arm A8 to receive the wafer W subjected to the exposure processing from the exposure apparatus 3 and return the wafer W to the shelf unit U11.

  Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U11 to each unit in the processing module 17, and performs the developing process on the resist film of the wafer W and the liquid processing unit U1 and The heat treatment unit U2 is controlled. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W to the shelf unit U10, and controls the lift arm A7 and the delivery arm A1 to return the wafer W into the carrier 11. Thus, the coating and developing process is completed.

  The specific configuration of the substrate processing apparatus is not limited to the configuration of the coating and developing apparatus 2 exemplified above. The substrate processing apparatus may be of any type as long as it includes the liquid processing unit U1 for development processing (the liquid processing unit U1 of the processing module 17) and the controller 100 capable of controlling this.

[Developing unit]
Subsequently, the liquid processing unit U1 of the processing module 17 will be described in detail. The processing module 17 has a developing unit 20 as the liquid processing unit U1. As shown in FIG. 4, the developing unit 20 has a rotation holding unit 30 and a developer supply unit 40.

The rotation holding unit 30 holds and rotates the substrate. For example, the rotation holding unit 30 has a holding mechanism 31 and a rotation mechanism 32. The holding mechanism 31 supports the central portion of the wafer W arranged horizontally, and holds the wafer W by, for example, vacuum suction or the like. The rotation mechanism 32 incorporates, for example, an electric motor or the like as a power source, and rotates the holding mechanism 31 around a vertical rotation center RC.
Thus, the wafer W rotates around the rotation center RC.

  The developer supply unit 40 supplies the developer to the surface Wa of the wafer W. The developer is a processing solution for removing a portion to be removed of the resist film after exposure. The removal target portion of the resist film is a portion soluble in the developer after the exposure processing. When the developer is positive, the portion exposed in the exposure process is soluble in the developer. When the developer is negative, the part not exposed in the exposure process is soluble in the developer. An alkaline solution is mentioned as a specific example of a positive type developing solution. An organic solvent is mentioned as a specific example of a negative developing solution.

  The developer supply unit 40 includes, for example, a nozzle 41, a tank 44, a pump 46, a valve 47, and a nozzle conveyance mechanism 48.

  The nozzle 41 discharges the developing solution toward the surface Wa of the wafer W. As shown in FIG. 5, the nozzle 41 includes a discharge port 42 for the developer and a liquid contact surface 43 formed around the discharge port 42. For example, the nozzle 41 has a circular liquid contact surface 43, and the discharge port 42 opens at the central portion of the liquid contact surface 43. The area of the liquid contact surface 43 is smaller than the area of the surface Wa of the wafer W. The area of the liquid contact surface 43 is, for example, 1 to 11%, and may be 1 to 3% of the area of the surface Wa of the wafer W.

  Returning to FIG. 4, the nozzle 41 is connected to the tank 44 via the conduit 45. The tank 44 contains a developer. The pump 46 and the valve 47 are provided in the conduit 45. The pump 46 is, for example, a bellows pump, and pumps the developer from the tank 44 to the nozzle 41. The valve 47 is, for example, an air operation valve, and adjusts the degree of opening in the conduit 45. By controlling the valve 47, it is possible to switch between the state in which the developer is discharged from the nozzle 41 and the state in which the developer is not discharged from the nozzle 41. In addition, by controlling at least one of the pump 46 and the valve 47, it is also possible to adjust the discharge amount of the developing solution from the nozzle 41.

  The nozzle conveyance mechanism 48 conveys the nozzle 41 by using, for example, an electric motor or the like as a power source. Specifically, the nozzle transfer mechanism 48 transfers the nozzle 41 so as to cross the upper side of the wafer W in a state where the liquid contact surface 43 of the nozzle 41 is directed downward.

  The nozzle transfer mechanism 48 may transfer the nozzles 41 along a path passing through the rotation center RC of the wafer W, or may transfer the nozzles 41 along a path shifted with respect to the rotation center RC. The nozzle transfer mechanism 48 may transfer the nozzles 41 along a straight path, or may transfer the nozzles 41 along a curved path.

  In addition to transporting the nozzle 41 as described above, the nozzle transport mechanism 48 may be configured to move the nozzle 41 up and down. In other words, the nozzle transfer mechanism 48 has a mechanism for transferring the nozzle 41 across the upper side of the wafer W using an electric motor or the like as a power source, and a mechanism for moving the nozzle 41 up and down using the electric motor or the like as a power source. You may

  The rinse liquid supply unit 50 supplies the rinse liquid to the surface Wa of the wafer W. The rinse liquid is a processing liquid for washing away the developer, and is, for example, pure water.

  The rinse liquid supply unit 50 includes, for example, a nozzle 51, a tank 52, a pump 54, a valve 55, and a nozzle conveyance mechanism 56.

  The nozzle 51 discharges the rinse liquid toward the surface Wa of the wafer W. The nozzle 51 is connected to the tank 52 via a conduit 53. The tank 52 contains a rinse solution. The pump 54 and the valve 55 are provided in the conduit 53. The pump 54 is, for example, a bellows pump, and pumps the rinse liquid from the tank 52 to the nozzle 51. The valve 55 is, for example, an air operation valve, and adjusts the degree of opening in the conduit 53. By controlling the valve 55, it is possible to switch between a state in which the rinse liquid is discharged from the nozzle 51 and a state in which the rinse liquid is not discharged from the nozzle 51. In addition, by controlling at least one of the pump 54 and the valve 55, it is also possible to adjust the discharge amount of the rinse liquid from the nozzle 51.

  The nozzle transfer mechanism 56 transfers the nozzle 51 using, for example, an electric motor or the like as a power source. Specifically, the nozzle transfer mechanism 56 transfers the nozzle 51 so as to cross over the wafer W in a state where the discharge port of the nozzle 51 is directed downward.

  The developing unit 20 configured in this way is controlled by the controller 100 described above. The controller 100 controls the rotation holding unit 30 so as to rotate the wafer W at the first rotation number, and supplies the developer from the discharge port 42 to the surface Wa in a state where the liquid contact surface 43 faces the surface Wa. By forming the liquid film of the developer on the surface Wa by moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, and after the liquid film is formed on the surface Wa, the discharge port 42 is formed. Controlling the rotation holding unit 30 so as to rotate the wafer W at a second rotation number lower than the first rotation number in a state where supply of the developer from the developer is stopped, and rotating the wafer W at the second rotation number After rotation, the rotation holding unit 30 is controlled to rotate the wafer W at a third rotation number higher than the first rotation number, and after rotating the wafer W at the third rotation number, the rotation of the wafer W is performed. By setting the number to the second rotation speed or less, on the surface Wa Is configured to perform the controlling the rotation holding portion 30 to hold the film.

  For example, the controller 100 has a liquid film formation control unit 111, a liquid film adjustment control unit 112, a liquid film holding control unit 113, and a cleaning control unit 114 as a functional configuration (hereinafter referred to as "functional module"). , And a drying control unit 115. The liquid film formation control unit 111 controls the rotation holding unit 30 and the developer supply unit 40 so as to form a liquid film of the developer on the surface Wa. The liquid film adjustment control unit 112 controls the rotation holding unit 30 so as to adjust the state of the liquid film formed on the surface Wa by changing the rotational speed of the wafer W. The liquid film holding control unit 113 controls the rotation holding unit 30 to hold the liquid film on the surface Wa by reducing the number of rotations of the wafer W. The cleaning control unit 114 controls the rotation holding unit 30 and the rinse solution supply unit 50 so as to wash away the developer by supplying the rinse solution onto the surface Wa while rotating the wafer W. The drying control unit 115 controls the rotation holding unit 30 to shake off the liquid on the surface Wa by rotating the wafer W.

  Such a controller 100 is configured by, for example, one or more control computers. In this case, each functional module of the controller 100 is configured by the cooperation of the processor and memory of the control computer. The program for causing the control computer to function as the controller 100 may be recorded in a computer readable recording medium. In this case, the recording medium records a program for causing the apparatus to execute a substrate processing method described later. Examples of the computer readable recording medium include a hard disk, a compact disk, a flash memory, a flexible disk, a memory card and the like.

  The hardware that configures each functional module of the controller 100 is not necessarily limited to the processor, the memory, and the like. For example, each element of the controller 100 may be configured by an electric circuit specialized for the function, or may be configured by an application specific integrated circuit (ASIC) in which the electric circuit is integrated.

[Development processing procedure]
Subsequently, as an example of the substrate processing method, a development processing procedure executed by the coating and developing apparatus 2 will be described. In the procedure described below, after the wafer W before development processing is carried into the developing unit 20 by the transfer arm A3 and held by the holding mechanism 31, the wafer W after development processing is out of the developing unit 20 by the transfer arm A3. It is the procedure until it is taken out to the This procedure is executed by the controller 100 controlling each part of the developing unit 20.

  As shown in FIG. 6, the controller 100 first executes steps S01 to S05 in order. In step S01, the rotation holding unit 30 starts the rotation of the wafer W, and controls the rotation holding unit 30 so that the number of rotations thereof becomes the first rotation speed ω1 (see FIG. 7A). The first rotation number ω1 is a rotation number at which the developer supplied onto the surface Wa is kept on the surface Wa without being shaken off by the centrifugal force. Such a first rotation speed ω1 can be set as appropriate by taking conditions in advance. The first rotation speed ω1 is, for example, 40 to 90 rpm, and may be 55 to 65 rpm.

  In step S02, the liquid film formation control unit 111 controls the developing solution supply unit 40 such that the nozzle 41 is disposed at the application start position of the developing solution. The liquid film formation control unit 111 controls the developing solution supply unit 40 so that the wetted surface 43 faces the area of the surface Wa to which the developing solution is first applied by transferring the nozzle 41 by the nozzle transfer mechanism 48. Do. The area of the surface Wa to which the developer is first applied may be an area on the outer periphery Wb side of the wafer W. The region on the outer periphery Wb side is a region eccentric to one point side on the outer periphery Wb in the surface Wa.

  In step S03, the liquid film formation control unit 111 controls the developer supply unit 40 so as to supply the developer DF from the tank 44 to the nozzle 41 and to start the discharge of the developer DF from the nozzle 41 (FIG. 7). See (a)).

  In step S04, by moving the nozzle 41 by the nozzle transport mechanism 48 while bringing the liquid contact surface 43 into contact with the developer DF, the liquid film formation control is performed so that the liquid film LF of the developer DF is formed on the surface Wa. The unit 111 controls the developer supply unit 40 (see FIGS. 7B and 7C). For example, the liquid film formation control unit 111 controls the developer supply unit 40 so as to move the nozzle 41 along a path crossing the upper side of the surface Wa. As a result, the developer DF is helically applied on the surface Wa, and the liquid film LF is formed.

  The liquid film formation control unit 111 may control the developer supply unit 40 so as to move the nozzle 41 from the outer periphery Wb side of the wafer W to the rotation center RC side.

  The liquid film formation control unit 111 may control the developer supply unit 40 to change the moving speed of the nozzle 41 while the nozzle 41 is moving. For example, the liquid film formation control unit 111 may control the developing solution supply unit 40 so as to reduce the moving speed of the nozzle 41 in accordance with the approach of the discharge port 42 to the rotation center RC.

  The liquid film formation control unit 111 may control the developing solution supply unit 40 so as to change the discharge amount of the developing solution DF from the discharge port 42 while the nozzle 41 is moving. For example, the liquid film formation control unit 111 may control the developer supply unit 40 to increase the discharge amount of the developer DF from the discharge port 42 in response to the discharge port 42 approaching the rotation center RC.

  The liquid film formation control unit 111 may control the developer supply unit 40 such that the nozzle 41 is moved with the position where the discharge port 42 coincides with the rotation center RC as the end point. That is, the liquid film formation control unit 111 may control the developing solution supply unit 40 so as to stop the movement of the nozzle 41 when the discharge port 42 is positioned on the rotation center RC.

  The liquid film formation control unit 111 may control the developer supply unit 40 such that the nozzle 41 is moved with the position where the discharge port 42 deviates from the rotation center RC as an end point. For example, the liquid film formation control unit 111 may stop the movement of the nozzle 41 before the discharge port 42 reaches the rotation center RC (see FIG. 8A), or the discharge port 42 passes the rotation center RC. You may move the nozzle 41 until it does (refer FIG.8 (b)). In any case, the liquid film formation control unit 111 may use the position where the rotation center RC passes through the liquid contact surface 43 as the end point while the discharge port 42 is shifted from the rotation center RC.

  In step S05, the liquid film formation control unit 111 controls the developer supply unit 40 so as to stop the discharge of the developer DF from the nozzle 41.

  Next, the controller 100 sequentially executes steps S06 to S09. In step S06, the liquid film adjustment control unit 112 controls the rotation holding unit 30 so as to change the rotation number of the wafer W from the first rotation number ω1 to the second rotation number ω2. The second rotation speed ω2 is lower than the first rotation speed ω1. The second rotation speed ω2 can be appropriately set by taking out the conditions in advance. The second rotation speed ω2 is, for example, 0 to 20 rpm, and may be 5 to 15 rpm. As exemplified here, the second rotation speed ω2 may be zero. That is, changing the first rotation speed ω1 to the second rotation speed ω2 also includes stopping the rotation of the wafer W.

  In step S07, liquid film adjustment control unit 112 maintains the state after execution of step S06 (state in which the number of rotations of wafer W is equal to second rotation number ω2) and waits for the first processing time to elapse. . The first processing time can be appropriately set by taking out the conditions in advance. The first treatment time is, for example, 1 to 2 seconds.

  In step S08, the liquid film adjustment control unit 112 controls the rotation holding unit 30 to change the rotation number of the wafer W from the second rotation number ω2 to the third rotation number ω3. The third rotation speed ω3 is higher than the first rotation speed ω1. More specifically, the third rotation speed ω3 is a rotation speed at which a part of the developer DF forming the liquid film LF is moved to the outer periphery Wb side of the wafer W by centrifugal force. Such a third rotation speed ω3 can be set as appropriate by taking conditions in advance. The third rotation speed ω3 is, for example, 90 to 200 rpm, and may be 80 to 120 rpm.

  In step S09, the liquid film adjustment control unit 112 maintains the state after execution of step S08 (the state in which the number of rotations of the wafer W is the third number of rotations ω3) and waits for the second processing time to elapse. . The second processing time can be appropriately set by taking out the conditions in advance. The second processing time is, for example, 1 to 2 seconds.

  Steps S06 to S09 improve the uniformity of the film thickness of the liquid film LF and the concentration of the developer DF in the liquid film LF. The concentration of the developer DF means the concentration of the component contributing to the development process in the developer DF.

  The phenomenon that occurs in the liquid film LF by the execution of the steps S06 to S09 will be described with reference to FIG. In the process of forming the liquid film LF, when moving the nozzle 41 from the outer periphery Wb side of the wafer W to the rotation center RC side as described above, the developer supplied on the outer periphery Wb side is the developer on the rotation center RC side Precede the supply of As a result, the developer DF supplied to the outer periphery Wb degrades earlier than the developer supplied to the rotation center RC. Therefore, immediately after the formation of the liquid film LF, the developer becomes closer to the rotation center RC. The freshness of the The deterioration of the developer means that the concentration of the developer is lowered due to the progress of the development process and the like, and the freshness of the developer means less deterioration of the developer.

  FIG. 9 is a diagram showing the developer DF in the liquid film LF divided into a fresh developer DF1 and a deteriorated developer DF2 in order to schematically show the state of the developer DF in the liquid film LF. is there. As shown in FIG. 9A, immediately after the formation of the liquid film LF, the freshness of the developer becomes higher as the rotation center RC is approached.

  When the first rotation speed ω1 is changed to the second rotation speed ω2 in the above-described steps S06 and S07, the developer DF approaches the rotation center RC as shown in FIG. 9B. Thus, the fresh developer DF1 gathers on the rotation center RC side. Thereafter, when the second rotation speed ω2 is changed to the third rotation speed ω3 in steps S08 and S09, as shown in FIGS. 9C and 9D, the developer DF spreads to the outer circumference Wb side, which is an excess. The developer DF is shaken off to the outer peripheral side. Along with this, the fresh developer DF1 spreads to the outer periphery Wb side, and the deteriorated developer DF2 is replaced with the fresh developer DF1. Thereby, the uniformity of the film thickness of the liquid film LF and the concentration of the developer DF in the liquid film LF are enhanced.

  Step S06 may be performed prior to step S05. Step S05 may be performed at least before completion of step S07. That is, at least a part of the period in which the wafer W is rotated at the second rotation speed ω2 may be after the supply of the developer DF1 is stopped.

  After execution of step S04, until the completion of step S07, liquid film adjustment control unit 112 controls developer supply unit 40 so that nozzle 41 is raised and liquid contact surface 43 is separated from wafer W. May be further performed. That is, after the liquid film LF is formed on the wafer W, the liquid contact surface 43 of the wafer W from the wafer W is completed before the completion of the rotation of the wafer W at the second rotation speed ω 2. It may further include spacing. The liquid separation surface 43 may be separated from the wafer W either before or after step S05, or may be performed before or after step S06.

  To separate the liquid contact surface 43 from the wafer W is to separate the liquid contact surface 43 from the surface Wa to the first distance D1 at the first velocity V1 (see FIG. 10A); And the separation of the liquid contact surface 43 at a second velocity V2 lower than the first velocity V1 (see FIG. 10B). May be. That is, when the liquid film adjustment control unit 112 separates the liquid contact surface 43 from the wafer W, the liquid film adjustment control unit 112 separates the liquid contact surface 43 from the surface Wa to the first distance D1 and holds the state. The developer supply unit 40 may be controlled to further separate the liquid contact surface 43 at a second speed V2 lower than the above.

  The first distance D1 may be a distance at which the liquid column LC is formed between the liquid film LF and the liquid contact surface 43 (see FIG. 10A). Such a distance can be appropriately set by taking out the conditions in advance.

  Returning to FIG. 6, the controller 100 next executes steps S10 and S11. In step S10, the liquid film holding control unit 113 controls the rotation holding unit 30 to hold the liquid film LF on the surface Wa by setting the number of rotations of the wafer W to the second number of rotations ω2 or less. As one example, the liquid film holding control unit 113 may control the rotation holding unit 30 so as to stop the rotation of the wafer W.

  In step S11, the liquid film holding control unit 113 maintains the state after execution of step S10 (state in which the number of rotations of the wafer W is less than or equal to the second number of rotations 2) and stands by for the third processing time. Do. During this time, development progresses further by the developer DF in the liquid film LF. The third processing time can be appropriately set by taking out the conditions in advance. The third processing time is, for example, 10 to 30 seconds, and may be 15 to 25 seconds.

  Next, the controller 100 sequentially executes steps S12 to S14. In step S12, the cleaning control unit 114 controls the rinse solution supply unit 50 so that the nozzle 51 is transferred by the nozzle transfer mechanism 56 and disposed on the rotation center RC of the wafer W.

  In step S13, the cleaning control unit 114 controls the rotation holding unit 30 and the rinse solution supply unit 50 so as to wash out the developer DF on the surface Wa. For example, the cleaning control unit 114 sends the rinse liquid CF from the tank 52 to the nozzle 51 while controlling the rotation holding unit 30 so as to rotate the wafer W at the fourth rotation speed ω4 higher than the third rotation speed ω3. The rinse liquid supply unit 50 is controlled to supply the central part of Wa (see FIG. 11A). The fourth rotation speed ω4 can be appropriately set by taking out the conditions in advance. The fourth rotation speed ω4 is, for example, 500 to 2,000 rpm. The rinse liquid CF supplied onto the surface Wa rinses the developer DF while spreading to the outer circumference Wb side by the centrifugal force (see FIG. 11B). Thereafter, the cleaning control unit 114 controls the rinse solution supply unit 50 to stop the supply of the rinse solution CF.

  In step S14, the drying control unit 115 controls the rotation holding unit 30 so as to remove the liquid on the surface Wa. For example, the drying control unit 115 controls the rotation holding unit 30 to rotate the wafer W at the fifth rotation speed ω5 that is higher than the fourth rotation speed ω4 (see FIG. 11C). The fifth rotation speed ω5 is, for example, 1500 to 3000 rpm. Thus, the developing procedure is completed.

[Effect of this embodiment]
In the developing processing procedure according to the present embodiment, the developing solution is supplied from the discharge port 42 to the surface Wa in a state where the wafer W is rotated at the first rotation number and the wetted surface 43 is opposed to the surface Wa. By moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the liquid, the liquid film of the developer is formed on the surface Wa, and after the liquid film is formed on the surface Wa, the development from the discharge port 42 is performed. After the wafer W is rotated at a second rotation speed lower than the first rotation speed with the liquid supply stopped, and after the wafer W is rotated at the second rotation speed, the first rotation speed is higher than the first rotation speed. The liquid film is held on the surface Wa by rotating the wafer W at three rotations and rotating the wafer W at the third rotation, and setting the number of rotations of the wafer W equal to or less than the second rotation. And including.

  According to this development processing procedure, in the process of forming the liquid film, the liquid contact surface 43 contacts the developer supplied from the discharge port 42 to the surface Wa. The relative motion between the liquid contact surface 43 and the surface Wa causes the developer to be stirred between them. For this reason, the uniformity of the development progress speed between the liquid contact surface 43 and the surface Wa is enhanced.

  After the formation of the liquid film, the number of rotations of the wafer W is reduced from the first number of rotations to the second number of rotations, and is then increased to a third number of rotations higher than the first number of rotations. As the rotation speed of the wafer W decreases from the first rotation speed to the second rotation speed, the developer moves closer to the rotation center RC of the wafer W, and the rotation speed of the wafer W increases from the second rotation speed to the third rotation speed. As a result, the developer spreads on the outer periphery Wb side of the wafer W. By moving to the rotation center RC side before spreading to the outer circumference Wb side, the kinetic energy of the developer when spreading to the outer circumference Wb side increases, so the developer on the rotation center RC side is more surely to the outer circumference Wb side Go around. As a result, the liquid film is held on the surface Wa in a state where the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film is enhanced. For this reason, even after the formation of the liquid film, the uniformity of the development progress speed is enhanced.

  As described above, the uniformity of the development progress rate is enhanced both in the formation process of the liquid film and after the formation of the liquid film, so that it is possible to more reliably suppress the progress amount of development depending on the position on the substrate.

  When the liquid film is formed on the surface Wa by moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developing solution, the nozzle 41 may be moved from the outer periphery Wb to the rotation center RC. In this case, the supply of the developer on the side of the rotation center RC is performed later than the supply of the developer on the side of the outer periphery Wb, so immediately after the formation of the liquid film, the developer has a high degree of freshness as it approaches the rotation center RC. It becomes a state. Therefore, when the wafer W is rotated at the third rotation number, the developer on the outer periphery Wb with low freshness is replaced by the developer on the rotation center RC with high freshness. Since the uniformity of the concentration of the developer tends to increase as the freshness of the developer increases, the developer in the liquid film is replaced by replacing the developer with a low degree of freshness with the developer with a high degree of freshness. The uniformity of the concentration is further enhanced. This makes it possible to further improve the uniformity of the development speed.

  After forming the liquid film on the surface Wa, the method may further include separating the liquid contact surface 43 from the surface Wa before the rotation of the wafer W at the second rotation number is completed. In this case, the developer in the liquid film can be more reliably rotated on the side of the rotation center RC by expanding the area between the liquid contact surface 43 and the surface Wa before the rotation of the wafer W at the second rotation number is completed. Can be Therefore, when the wafer W is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be further enhanced.

  The separation of the liquid contact surface 43 from the surface Wa is performed by separating the liquid contact surface 43 from the surface Wa to a first distance at a first speed, and the liquid contact surface 43 is separated from the surface Wa to a first distance After holding the state, the liquid contact surface 43 may be further separated at a second velocity lower than the first velocity. In this case, after the wetted surface 43 is separated from the surface Wa to the first distance at the first velocity, the wetted surface 43 and the liquid film are held by maintaining the distance between the wetted surface 43 and the surface Wa. Contact surface is reduced. Thereafter, by further separating the liquid contact surface 43 at a second speed lower than the first speed, the peeling of the developing solution when the liquid contact surface 43 is separated from the liquid film is suppressed. From these things, when the liquid contact surface 43 is separated from the liquid film, the developer does not easily remain on the liquid contact surface 43, so generation of liquid dripping from the liquid contact surface 43 separated from the liquid film is suppressed. . Therefore, when the wafer W is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be further enhanced.

  The first distance may be a distance at which a liquid column is formed between the liquid film of the developer and the liquid contact surface 43. In this case, in the process of separating the wetted surface 43 from the surface Wa to the first distance, the contact surface between the wetted surface 43 and the liquid film is reduced more reliably in a state in which the developing solution is prevented from being separated. Therefore, when the liquid contact surface 43 is separated from the liquid film, the developer can be more reliably prevented from remaining on the liquid contact surface 43.

  By moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, when forming a liquid film on the surface Wa, the moving speed of the nozzle 41 may be changed halfway. In this case, by changing the moving speed of the nozzle 41, the amount of the developer on the side of the rotation center RC of the liquid film can be more properly optimized. Therefore, when the wafer W is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved.

  By moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, when forming a liquid film on the surface Wa, the moving speed of the nozzle 41 is adjusted according to the discharge port 42 approaching the rotation center RC. It may be reduced. In this case, immediately after the formation of the liquid film, the amount of the developer on the rotation center RC side of the liquid film is larger than the amount of the developer on the outer periphery Wb side of the liquid film. Therefore, when the wafer W is rotated at the third rotation number, the developer on the rotation center RC side is more reliably spread to the outer periphery Wb side, so that the film thickness of the liquid film and the concentration of the developer in the liquid film are uniform. It is possible to increase the sex more reliably.

  When the liquid film is formed on the surface Wa by moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, the discharge amount of the developer from the discharge port 42 may be changed halfway. In this case, by changing the discharge amount of the developer from the discharge port 42, the amount of the developer on the side of the rotation center RC of the liquid film can be more properly optimized. Therefore, when the wafer W is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved.

  By moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, when forming a liquid film on the surface Wa, the development from the discharge port 42 according to the discharge port 42 approaching the rotation center RC. The discharge amount of the liquid may be increased. In this case, immediately after the formation of the liquid film, the amount of the developer on the rotation center RC side of the liquid film is larger than the amount of the developer on the outer periphery Wb side of the liquid film. Therefore, when the wafer W is rotated at the third rotation number, the developer on the rotation center RC side is more reliably spread to the outer periphery Wb side, so that the film thickness of the liquid film and the concentration of the developer in the liquid film are uniform. It is possible to increase the sex more reliably.

  By moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, when forming a liquid film on the surface Wa, the nozzle 41 is moved with the position at which the discharge port 42 deviates from the rotation center RC as the end point. It is also good. In this case, the amount of developer on the side of the rotation center RC of the liquid film can be adjusted by the position at which the movement of the nozzle 41 is stopped. For example, by stopping the movement of the nozzle 41 before the discharge port 42 reaches the rotation center of the wafer W, the amount of the developer on the rotation center RC side can be reduced. On the other hand, by moving the nozzle 41 until the discharge port 42 passes the rotation center RC, the amount of the developer on the rotation center RC side of the liquid film can be increased. Therefore, the amount of the developer on the side of the rotation center RC of the liquid film can be more properly optimized by the position at which the movement of the nozzle 41 is stopped. Therefore, when the wafer W is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved.

  By moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, when forming a liquid film on the surface Wa, the discharge port 42 deviates from the rotation center RC, and the rotation center RC contacts the liquid contact surface 43. The nozzle 41 may be moved with the passing position as an end point. In this case, even in the case where the movement of the nozzle 41 is stopped at the position where the discharge port 42 deviates from the rotation center RC, the range in which the liquid contact surface 43 of the nozzle 41 faces extends over the entire surface Wa. Therefore, the developer can be applied to the rotation center RC more reliably. Therefore, when the wafer W is rotated at the third rotation number, the uniformity of the film thickness of the liquid film and the concentration of the developer in the liquid film can be more reliably improved.

  When the liquid film is formed on the surface Wa by moving the nozzle 41 while bringing the liquid contact surface 43 into contact with the developer, the nozzle 41 may be moved until the discharge port 42 passes the rotation center RC. . In this case, immediately after the formation of the liquid film, the amount of the developer on the rotation center RC side of the liquid film is larger than the amount of the developer on the outer periphery Wb side of the liquid film. Therefore, when the wafer W is rotated at the third rotation number, the developer on the rotation center RC side is more reliably spread to the outer periphery Wb side, so that the film thickness of the liquid film and the concentration of the developer in the liquid film are uniform. It is possible to increase the sex more reliably.

  As mentioned above, although embodiment was described, this indication is not necessarily limited to embodiment mentioned above, A various change is possible in the range which does not deviate from the summary. For example, in the embodiment described above, the case where the nozzle 41 is moved from the outer periphery Wb side to the rotation center RC side when forming the liquid film on the surface Wa of the wafer W has been illustrated. When forming a liquid film on the surface Wa, the nozzle 41 may be moved from the rotation center RC side to the outer periphery Wb side.

  The substrate to be processed is not limited to a semiconductor wafer, and may be, for example, a glass substrate, a mask substrate, an FPD (Flat Panel Display), or the like.

  Then, although the Example and comparative example of development procedure are shown, this invention is not limited to the example shown here.

[Preparation of wafer sample]
A resist film was formed on a plurality of wafers W, and the resist film was subjected to exposure processing by the step-and-repeat method. The exposure conditions for each shot were set to form linear patterns of about 45 nm in width at equal intervals.

〔Example〕
The development process of the above-described embodiment was performed on the wafer W subjected to the exposure process, and a resist pattern was formed on the surface Wa of the wafer W.

Comparative Example 1
The resist pattern was formed on the surface Wa of the wafer W in the same manner as in Example 1 except that steps S06 and S07 described above were omitted. That is, in Comparative Example 1, after the formation of the liquid film, the number of rotations of the wafer W was not reduced to the second number of rotations.

Comparative Example 2
The resist pattern was formed on the surface Wa of the wafer W in the same manner as in Example 1 except that steps S06 to S09 described above were omitted. That is, in Comparative Example 2, after the liquid film was formed, the number of revolutions of wafer W was not reduced to the second number of revolutions, and the number of revolutions of wafer W was not increased to the third number of revolutions. .

[Evaluation of variation in line width between shots]
For the resist patterns produced in the example and the comparative examples 1 and 2, nine measurement points were set for each shot, and the line width was measured at each measurement point. Using a line width data group obtained by calculating the average value of line widths for each shot as a population, a standard deviation was calculated, and a triple value thereof was calculated as a first variation evaluation value.

[Evaluation of variation in line width within a shot]
For the resist patterns produced in the example and the comparative examples 1 and 2, nine measurement points were set for each shot, and the line width was measured at each measurement point. The standard deviation was calculated with all line width data obtained by this measurement as a population, and the triple was calculated as a second variation evaluation value.

[Comparison result of variation evaluation value]
The first variation evaluation value was about 40% smaller than the wafer W of Comparative Example 2 for the wafer W of Comparative Example 1. From this result, it was confirmed that the variation in the amount of progress of development can be suppressed by increasing the number of rotations of the wafer W to the third number of rotations after the formation of the liquid film to adjust the state of the liquid film.

  The first variation evaluation value was about 9% smaller than the wafer W of Comparative Example 1 for the wafer W of Example 1. From this result, it is confirmed that the variation in the amount of progress of development can be further suppressed by decreasing the rotational speed of the wafer W to the second rotational speed before increasing the rotational speed of the wafer W to the third rotational speed after forming the liquid film.

  The wafer W of Example 1 had a second variation evaluation value smaller than that of the wafer W of Comparative Example 1 by about 5%. From this result, it is confirmed that the variation in the amount of progress of development can be further suppressed by decreasing the rotation speed of the wafer W to the second rotation speed before raising the rotation speed of the wafer W to the third rotation speed after forming the liquid film. It was done.

  2: coating / developing apparatus (substrate processing apparatus), 30: rotation holding unit, 40: developer supply unit, 41: nozzle, 42: discharge port, 43: liquid contact surface, 48: nozzle conveyance mechanism, 100: controller, D1: first distance, DF: developer, LC: liquid column, LF: liquid film, RC: rotation center, V1: first speed, V2: second speed, W: wafer, Wa: surface, Wb: outer periphery, ω1 ... first rotation number, ω2 ... second rotation number, ω3 ... third rotation number.

Claims (14)

The substrate is rotated at a first rotation number, and a developer is supplied from the discharge port to the surface of the substrate, with the liquid contact surface formed around the discharge port of the nozzle facing the surface of the substrate. Forming a liquid film of the developer on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developer;
After the liquid film is formed on the surface of the substrate, in a state in which the supply of the developer from the discharge port is stopped, the number of rotations of the substrate is lower than the first number of rotations ; and be Rukoto,
Rotating the substrate at a third rotation number higher than the first rotation number after rotating the substrate at the second rotation number;
And holding the liquid film on the surface of the substrate by setting the number of rotations of the substrate equal to or less than the second number of rotations after rotating the substrate at the third number of rotations. Method.   When the liquid film is formed on the surface of the substrate, the nozzle is moved from the outer peripheral side of the substrate to the rotation center side by moving the nozzle while bringing the liquid contact surface into contact with the developer. The substrate processing method according to claim 1.   The method may further include separating the liquid contact surface from the surface of the substrate after forming the liquid film on the surface of the substrate and before completing the rotation of the substrate at the second number of rotations. The substrate processing method of 2. The separation of the liquid contact surface from the surface of the substrate is
Separating the wetted surface from the surface of the substrate to a first distance at a first velocity;
And, after the liquid contact surface is kept separated from the surface of the substrate by the first distance, further separating the liquid contact surface at a second speed lower than the first speed. The substrate processing method of 3.   The substrate processing method according to claim 4, wherein the first distance is a distance at which a liquid column is formed between a liquid film of the developer and the liquid contact surface.   The moving speed of the nozzle is changed midway when the liquid film is formed on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developer. 5. The substrate processing method according to any one of 5.   By moving the nozzle while bringing the liquid contact surface into contact with the developer, when the liquid film is formed on the surface of the substrate, the discharge port approaches the rotation center of the substrate. The substrate processing method according to claim 6, wherein the moving speed of the nozzle is reduced.   By moving the nozzle while bringing the liquid contact surface into contact with the developer, when forming the liquid film on the surface of the substrate, the discharge amount of the developer from the discharge port is changed halfway The substrate processing method according to any one of claims 2 to 7, wherein   By moving the nozzle while bringing the liquid contact surface into contact with the developer, when the liquid film is formed on the surface of the substrate, the discharge port approaches the rotation center of the substrate. The substrate processing method according to claim 8, wherein the discharge amount of the developer from the discharge port is increased.   When the liquid film is formed on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developing solution, the position at which the discharge port deviates from the rotation center of the substrate is taken as an end point. The substrate processing method according to any one of claims 2 to 9, wherein the nozzle is moved.   By moving the nozzle while bringing the liquid contact surface into contact with the developer, when the liquid film is formed on the surface of the substrate, the discharge port deviates from the rotation center of the substrate, and the substrate The substrate processing method according to claim 10, wherein the nozzle is moved with an end point at which the rotation center passes through the liquid contact surface.   When the liquid film is formed on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developer, the nozzle until the discharge port passes the rotation center of the substrate The substrate processing method according to claim 10 or 11, wherein A rotary holder that holds and rotates the substrate;
A nozzle including a discharge port for developing solution, a liquid contact surface formed around the discharge port, and a nozzle transfer mechanism for transferring the nozzle, and supplying the developing solution to the surface of the substrate The developer supply unit
And a controller,
The controller
The rotation holding unit is controlled to rotate the substrate at a first rotation number, and the developer is supplied from the discharge port to the surface of the substrate in a state where the liquid contact surface is opposed to the surface of the substrate. Controlling the developer supply unit to form a liquid film of the developer on the surface of the substrate by moving the nozzle while bringing the liquid contact surface into contact with the developer;
After the liquid film is formed on the surface of the substrate, in a state in which the supply of the developer from the discharge port is stopped, the number of rotations of the substrate is lower than the first number of rotations ; and controlling the rotation holding portion to be so that,
Controlling the rotation holding unit to rotate the substrate at a third rotation number higher than the first rotation number after rotating the substrate at the second rotation number;
After the substrate is rotated at the third rotation number, the rotation holding portion is set to hold the liquid film on the surface of the substrate by making the rotation number of the substrate equal to or less than the second rotation number. A substrate processing apparatus configured to perform controlling.   A computer readable recording medium having recorded thereon a program for causing a substrate processing apparatus to execute the substrate processing method according to any one of claims 1 to 12.

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