JP2019033157A - Substrate processing method, storage medium, and substrate processing device - Google Patents

Abstract

To provide a substrate processing method capable of suppressing generation of particles at a peripheral portion of a substrate.SOLUTION: In a substrate processing method according to the present invention, firstly, a substrate W is held horizontally. Subsequently, rotation of the substrate W having been held is started. After that, a first process liquid for hydrophobizing the substrate W, the first process liquid containing hydrofluoric acid, is supplied on a film formed at a peripheral portion of the substrate W that is rotating thereby to remove the film, and a second process liquid for hydrophilizing the substrate W is supplied to the first process liquid on the substrate W.SELECTED DRAWING: Figure 5E

Description

  The present invention relates to a substrate processing method, a storage medium, and a substrate processing apparatus.

  In a manufacturing process of a semiconductor device in which a laminated structure of integrated circuits is formed on the surface of a semiconductor wafer (hereinafter referred to as a wafer) as a substrate, a natural oxide film formed on the peripheral edge (edge region) of the wafer is treated with hydrofluoric acid. It is performed to remove with a chemical solution such as (see, for example, Patent Document 1).

JP 2011-66194 A

  By the way, when the natural oxide film is removed with hydrofluoric acid, the chemical solution touches the silicon wafer. Normally, the surface of the wafer is hydrophilic due to a hydroxyl group (—OH), but this hydroxyl group is changed to a hydrogen termination (—H) by hydrofluoric acid. This makes the surface of the wafer hydrophobic. When hydrofluoric acid is supplied to the hydrophobized surface, the hydrofluoric acid scatters (splashes) to the inner peripheral side from the supply position, and can become a particle source. In particular, in recent years, the particle inspection target has become smaller in size, and the particle inspection range has been expanded in the radial direction, and particle countermeasures are urgently needed.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a substrate processing method, a storage medium, and a substrate processing apparatus capable of suppressing the generation of particles at the peripheral edge of the substrate. .

One embodiment of the present invention
A substrate processing method for removing a film formed on a peripheral portion of a substrate,
Holding step for holding the substrate horizontally;
A rotation start step for starting rotation of the held substrate;
A first treatment liquid containing hydrofluoric acid for hydrophobizing the substrate is supplied to the film formed on the peripheral edge of the rotating substrate to remove the film, and the first treatment on the substrate. A substrate treatment method comprising: a treatment liquid supply step of supplying a second treatment solution for hydrophilizing the substrate to the solution;
I will provide a.

One embodiment of the present invention
When executed by a computer for controlling the operation of the substrate processing apparatus, the computer controls the substrate processing apparatus to execute the substrate processing method according to any one of claims 1 to 6. A storage medium on which the program is recorded,
I will provide a.

Other embodiments of the invention include:
A substrate processing apparatus for removing a film formed on a peripheral portion of a substrate,
A holding unit for holding the substrate horizontally;
A rotation drive unit for rotating the holding unit;
A first processing liquid supply including a first processing liquid nozzle that supplies a first processing liquid containing hydrofluoric acid that hydrophobizes the substrate to the film formed on the peripheral edge of the substrate held by the holding unit. And
A second processing liquid supply unit including a second processing liquid nozzle for supplying a second processing liquid for hydrophilizing the substrate to the first processing liquid on the substrate;
A control unit,
The control unit drives the rotation driving unit to start rotation of the substrate held by the holding unit, and then supplies the first processing liquid from the first processing liquid nozzle to the rotating substrate. A substrate processing apparatus for controlling the rotation driving unit, the first processing liquid supply unit, and the second processing liquid supply unit so as to supply the second processing liquid from the second processing liquid nozzle;
I will provide a.

  According to the present invention, generation of particles at the peripheral edge of the substrate can be suppressed.

FIG. 1 is a diagram showing a schematic configuration of a substrate processing system in the present embodiment. FIG. 2 is a schematic longitudinal sectional view of the substrate processing apparatus in the present embodiment. FIG. 3 is a schematic plan view showing each nozzle of FIG. FIG. 4 is a control block diagram of the substrate processing apparatus shown in FIG. FIG. 5A is a schematic plan view for explaining a rotation start step in the substrate processing method in the present embodiment. FIG. 5B is a schematic plan view for explaining a discharge start process of hydrofluoric acid and SC1, following the rotation start process shown in FIG. 5A. FIG. 5C is a schematic plan view for explaining a second treatment liquid nozzle advancement step subsequent to the discharge start step shown in FIG. 5B. FIG. 5D is a schematic plan view for explaining a first process liquid nozzle advancement process subsequent to the second process liquid nozzle advancement process illustrated in FIG. 5C. FIG. 5E is a schematic plan view for explaining a natural oxide film removal step subsequent to the first treatment liquid nozzle advancement step shown in FIG. 5D. FIG. 5F is a schematic plan view for explaining a first treatment liquid nozzle retreating step subsequent to the natural oxide film removing step shown in FIG. 5E. FIG. 5G is a schematic plan view for explaining a second process liquid nozzle retracting process subsequent to the first process liquid nozzle retracting process shown in FIG. 5F. FIG. 6A is a schematic plan view for explaining a DIW discharge start process subsequent to the second treatment liquid nozzle receding process shown in FIG. 5G. FIG. 6B is a schematic plan view for explaining a DIW nozzle advancement step subsequent to the discharge start step shown in FIG. 6A. FIG. 6C is a schematic plan view for explaining a rinsing process subsequent to the DIW nozzle advancement process shown in FIG. 6B. FIG. 6D is a schematic plan view for explaining a DIW nozzle retracting step subsequent to the rinsing process shown in FIG. 6C. FIG. 7 is a schematic plan view for explaining a wafer drying process subsequent to the DIW nozzle retracting process shown in FIG. 6D. FIG. 8 is a schematic plan view for explaining a modification of the natural oxide film removing step shown in FIG. 5E.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a substrate processing method, a storage medium, and a substrate processing apparatus of the present invention will be described with reference to the drawings. In addition, the structure shown in drawing attached to this specification may contain the part from which size and the scale etc. were changed from those of the real thing for convenience of illustration and understanding.

  FIG. 1 is a diagram showing a schematic configuration of a substrate processing system according to the present embodiment. In the following, in order to clarify the positional relationship, the X axis, the Y axis, and the Z axis that are orthogonal to each other are defined, and the positive direction of the Z axis is the vertically upward direction.

  As shown in FIG. 1, the substrate processing system 1 includes a carry-in / out station 2 and a processing station 3. The carry-in / out station 2 and the processing station 3 are provided adjacent to each other.

  The carry-in / out station 2 includes a carrier placement unit 11 and a transport unit 12. A plurality of carriers C that accommodate a plurality of substrates, in this embodiment a semiconductor wafer (hereinafter referred to as a wafer W) in a horizontal state, are placed on the carrier placement unit 11.

  The transport unit 12 is provided adjacent to the carrier placement unit 11 and includes a substrate transport device 13 and a delivery unit 14 inside. The substrate transfer device 13 includes a wafer holding mechanism that holds the wafer W. Further, the substrate transfer device 13 can move in the horizontal direction and the vertical direction and can turn around the vertical axis, and transfers the wafer W between the carrier C and the delivery unit 14 using the wafer holding mechanism. Do.

  The processing station 3 is provided adjacent to the transfer unit 12. The processing station 3 includes a transport unit 15 and a plurality of processing units 16. The plurality of processing units 16 are provided side by side on the transport unit 15.

  The transport unit 15 includes a substrate transport device 17 inside. The substrate transfer device 17 includes a wafer holding mechanism that holds the wafer W. Further, the substrate transfer device 17 can move in the horizontal direction and the vertical direction and can turn around the vertical axis, and transfers the wafer W between the delivery unit 14 and the processing unit 16 using a wafer holding mechanism. I do.

  The processing unit 16 performs predetermined substrate processing on the wafer W transferred by the substrate transfer device 17.

  Further, the substrate processing system 1 includes a control device 4. The control device 4 is a computer, for example, and includes a control unit 18 and a storage unit 19. The storage unit 19 stores a program for controlling various processes executed in the substrate processing system 1. The control unit 18 controls the operation of the substrate processing system 1 by reading and executing the program stored in the storage unit 19.

  Such a program may be recorded on a computer-readable storage medium, and may be installed in the storage unit 19 of the control device 4 from the storage medium. Examples of the computer-readable storage medium include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical disk (MO), and a memory card.

  In the substrate processing system 1 configured as described above, first, the substrate transfer device 13 of the loading / unloading station 2 takes out the wafer W from the carrier C placed on the carrier placement unit 11 and receives the taken-out wafer W. Place on the transfer section 14. The wafer W placed on the delivery unit 14 is taken out from the delivery unit 14 by the substrate transfer device 17 of the processing station 3 and carried into the processing unit 16.

  The wafer W loaded into the processing unit 16 is processed by the processing unit 16, then unloaded from the processing unit 16 by the substrate transfer device 17, and placed on the delivery unit 14. Then, the processed wafer W placed on the delivery unit 14 is returned to the carrier C of the carrier platform 11 by the substrate transfer device 13.

  The processing unit 16 shown in FIG. 1 includes the substrate processing apparatus 30 shown in FIG. Here, the substrate processing apparatus 30 in the present embodiment is an apparatus for removing a natural oxide film formed on the peripheral portion of the wafer W.

  As shown in FIG. 2, the substrate processing apparatus 30 includes a holding unit 31 that horizontally holds a substrate W such as a silicon semiconductor wafer (hereinafter also referred to as a wafer W), and a rotating shaft 32 that extends downward from the holding unit 31. And a rotation drive unit 33 that rotates the holding unit 31 via the rotation shaft 32. The holding unit 31 holds the wafer W placed on the holding unit 31 by, for example, vacuum suction.

  As shown in FIG. 1, the rotating shaft 32 extends in the vertical direction. The rotation drive unit 33 includes a pulley 34 provided at the lower end of the rotation shaft 32, a motor 35, a pulley 36 provided on the rotation shaft of the motor 35, and a drive belt wound around the pulley 34 and the pulley 36. 37. With such a configuration, the rotational driving force of the motor 35 is transmitted to the rotary shaft 32 via the drive belt 37. The rotating shaft 32 is rotatably held in the chamber 39 via a bearing 38.

  The holding unit 31 is accommodated in the chamber 39. In the upper part (ceiling part) of the chamber 39, an upper opening 40 through which a gas such as N 2 gas (nitrogen gas) passes through the wafer W in a down flow is formed. In addition, a lower opening 41 is formed in the lower portion (bottom portion) of the chamber 39 for discharging the gas sent from the upper opening 40 by a down flow from the chamber 39. Further, a side opening 42 for carrying the wafer W into the chamber 39 and carrying the wafer W out of the chamber 39 is formed at the side of the chamber 39. The side opening 42 is provided with a shutter 43 that can be opened and closed.

  As shown in FIGS. 2 and 3, a first processing liquid nozzle 51 for supplying hydrofluoric acid to the peripheral portion of the wafer W held by the holding unit 31 is provided in the chamber 39. The first processing liquid nozzle 51 is configured to discharge hydrofluoric acid at a predetermined angle with respect to the surface of the wafer W. More specifically, although the illustration is simplified in FIG. 2, in a longitudinal sectional view, the discharge angle of hydrofluoric acid is inclined at a predetermined angle with respect to the horizontal line, and the discharged hydrofluoric acid is vertical. It is discharged obliquely toward the downstream side in the rotation direction of the wafer W from below. Further, in a plan view, hydrofluoric acid discharged from the first processing liquid nozzle 51 is discharged obliquely toward the downstream side in the rotation direction of the wafer W from the outside in the radial direction of the wafer W. Similar to the first processing liquid nozzle 51, a second processing liquid nozzle 61 and a DIW nozzle 71 are also provided. As shown in FIG. 3, the second processing liquid nozzle 61 and the DIW nozzle 71 are arranged at different positions in the circumferential direction of the wafer W with respect to the first processing liquid nozzle 51.

  As shown in FIG. 2, the first processing liquid nozzle 51 supplies hydrofluoric acid (HF, first processing liquid) to the peripheral edge of the wafer W held by the holding unit 31. More specifically, a first processing liquid supply source 53 is connected to the first processing liquid nozzle 51 via a first processing liquid supply pipe 52, and the first processing liquid supply source 53 connects the first processing liquid supply source 53. Hydrofluoric acid is supplied to the first processing liquid nozzle 51 via the supply pipe 52. The first processing liquid supply pipe 52 is provided with a first processing liquid valve 54 that controls the presence or absence and supply amount of hydrofluoric acid to the first processing liquid nozzle 51. The first processing liquid nozzle 51, the first processing liquid supply pipe 52, the first processing liquid supply source 53, and the first processing liquid valve 54 supply hydrofluoric acid to the peripheral portion of the wafer W held by the holding unit 31. A first treatment liquid supply unit 50 is configured.

  The second processing liquid nozzle 61 supplies SC1 (a mixed liquid of ammonia and hydrogen peroxide, a second processing liquid) to the peripheral edge of the wafer W held by the holding section 31. More specifically, a second processing liquid supply source 63 is connected to the second processing liquid nozzle 61 via a second processing liquid supply pipe 62, and the second processing liquid supply source 63 connects to the second processing liquid supply source 63. SC1 is supplied to the second processing liquid nozzle 61 through the supply pipe 62. The second processing liquid supply pipe 62 is provided with a second processing liquid valve 64 that controls whether or not SC1 is supplied to the second processing liquid nozzle 61 and the supply amount. The SC1 is supplied to the peripheral portion of the wafer W held by the holding unit 31 by the second processing liquid nozzle 61, the second processing liquid supply pipe 62, the second processing liquid supply source 63, and the second processing liquid valve 64. A second processing liquid supply unit 60 is configured.

  The DIW nozzle 71 supplies DIW (deionized water) to the peripheral portion of the wafer W held by the holding unit 31. More specifically, a DIW supply source 73 is connected to the DIW nozzle 71 via a DIW supply pipe 72, and DIW is supplied from the DIW supply source 73 to the DIW nozzle 71 via the DIW supply pipe 72. It is like that. The DIW supply pipe 72 is provided with a DIW valve 74 that controls whether or not DIW is supplied to the DIW nozzle 71 and the supply amount. The DIW nozzle 71, the DIW supply pipe 72, the DIW supply source 73, and the DIW valve 74 constitute a DIW supply unit 70 that supplies DIW to the peripheral edge of the wafer W held by the holding unit 31.

  As shown in FIG. 3, the first processing liquid nozzle 51 is connected to a first processing liquid nozzle driving unit 55. The first processing liquid nozzle drive unit 55 moves the first processing liquid nozzle 51 between a first forward position P1 for supplying hydrofluoric acid to the peripheral edge of the wafer W and a first backward position Q1 retracted from the wafer W. The first processing liquid nozzle 51 is moved forward and backward. The first processing liquid nozzle 51 moves in the radial direction of the wafer W between the first forward position P1 and the first backward position Q1. The first advance position P1 is set to a position where hydrofluoric acid can be supplied so that the peripheral edge (region extending from the outer edge to a predetermined width) of the natural oxide film formed on the surface of the wafer W can be removed. The first retreat position Q1 is set to a position where the hydrofluoric acid discharged from the first processing liquid nozzle 51 does not reach the surface of the wafer W.

  The second processing liquid nozzle 61 is connected to the second processing liquid nozzle driving unit 65. The second processing liquid nozzle driving unit 65 causes the second processing liquid nozzle 61 to move between the second forward position P2 for supplying SC1 to the peripheral edge of the wafer W and the second backward position Q2 retracted from the wafer W. The second treatment liquid nozzle 61 is moved forward and backward. The second processing liquid nozzle 61 moves in the radial direction of the wafer W between the second forward position P2 and the second backward position Q2. The second advance position P2 is set to a position where SC1 can be supplied to the hydrofluoric acid remaining on the surface of the wafer W and before drying. More specifically, the second advance position P2 is such that the SC1 supply position to the wafer W is located closer to the downstream side in the rotation direction of the wafer W than the hydrofluoric acid supply position to the wafer W. Is in position. The second forward position P2 is such that the SC1 supply position to the wafer W is closer to the center O of the wafer W than the hydrofluoric acid supply position to the wafer W. That is, the distance from the center O of the wafer W to the SC1 supply position is shorter than the distance from the center O to the hydrofluoric acid supply position. The second retracted position Q2 is set at a position where SC1 discharged from the second processing liquid nozzle 61 does not reach the surface of the wafer W.

  The DIW nozzle 71 is connected to the DIW nozzle driving unit 75. The DIW nozzle driving unit 75 moves the DIW nozzle 71 forward and between the third forward position P3 for supplying DIW to the peripheral edge of the wafer W and the third backward position Q3 retracted from the wafer W. Retreat. The DIW nozzle 71 moves in the radial direction of the wafer W between the third forward position P3 and the third backward position Q3. The third forward position P3 is set to a position where DIW can be supplied so that the hydrofluoric acid and SC1 remaining on the surface of the wafer W can be washed away. More specifically, the third forward position P3 is such that the DIW supply position to the wafer W is closer to the center O of the wafer W than the SC1 supply position to the wafer W. That is, the distance from the center O of the wafer W to the DIW supply position is shorter than the distance from the center O to the SC1 supply position. The third retracted position Q3 is set to a position where the DIW from which DIW is discharged from the DIW nozzle 71 does not reach the surface of the wafer W.

  As shown in FIG. 4, each component of the substrate processing apparatus 30 is controlled by the control unit 18 of the control apparatus 4 described above. Specifically, the holding unit 31, the rotation driving unit 33, the first processing liquid supply unit 50, the second processing liquid supply unit 60, and the DIW supply unit 70 are connected to the control unit 18, respectively. The control unit 18 is connected to a first processing liquid nozzle driving unit 55, a second processing liquid nozzle driving unit 65, and a DIW nozzle driving unit 75. The control unit 18 controls each component by sending a control signal to each component connected to the control unit 18. Specific contents of control of each component by the control unit 18 will be described later.

  Next, the operation of the substrate processing apparatus 30 as described above (method for processing the wafer W) will be described with reference to the explanatory diagrams shown in FIGS. 5A to 5G, FIGS. 6A to 6D, and FIG. The operation of the substrate processing apparatus 30 as described below is performed by the control unit 18 controlling each component of the substrate processing apparatus 30 according to a program (recipe) stored in the storage medium.

[Holding process]
First, the wafer W is held horizontally. More specifically, the wafer W is transferred from the outside of the substrate processing apparatus 30 into the chamber 39 through the side opening 42 of the chamber 39 by the substrate transfer apparatus 17 shown in FIG. Specifically, the wafer W is placed on the holding unit 31 in the chamber 39 by the substrate transfer device 17. Here, a hydrophilic natural oxide film is formed on the surface of the wafer W placed on the holding unit 31.

[Rotation start process]
Next, as shown in FIG. 5A, rotation of the wafer W held by the holding unit 31 is started. More specifically, the rotation drive part 33 (refer FIG. 2) is driven, and the rotating shaft 32 is rotated centering | focusing on the axis line extended in a perpendicular direction. As a result, the wafer W held by the holding unit 31 is rotated in the horizontal plane. At this time, the rotational shaft 32 is rotated by applying the rotational driving force of the motor 35 to the rotational shaft 32 via the pulley 36, the drive belt 37 and the pulley 34. Here, for example, the rotation speed of the wafer W is set to 1800 rpm.

[Processing liquid supply process]
Next, hydrofluoric acid and SC1 are supplied to the peripheral edge of the wafer W. That is, hydrofluoric acid that hydrophobizes the surface of the wafer W is supplied from the first processing liquid nozzle 51 to the natural oxide film formed on the peripheral edge of the rotating wafer W, and the natural oxide film is removed. Further, SC1 for hydrophilizing the wafer W is supplied from the second processing liquid nozzle 61 to hydrofluoric acid on the surface of the wafer W.

<Discharge start process>
In this processing liquid supply step, first, the first processing liquid valve 54 (see FIG. 2) is opened, and hydrofluoric acid is discharged from the first processing liquid nozzle 51 located at the first retracted position Q1, as shown in FIG. 5B. Is done. Further, the second processing liquid valve 64 is opened, and SC1 is discharged from the second processing liquid nozzle 61 located at the second retracted position Q2. While the first treatment liquid nozzle 51 is maintained at the first retracted position Q1 and the second process liquid nozzle 61 is maintained at the second retracted position Q2, hydrofluoric acid and SC1 are discharged for a predetermined time. Thus, even when the discharge amounts of hydrofluoric acid and SC1 are small, the discharge amounts of hydrofluoric acid and SC1 can be stabilized. For example, hydrofluoric acid and SC1 continue to be discharged at a discharge rate of 15 mL / min for 3 seconds, respectively.

<Second treatment liquid nozzle advance step>
Next, as shown in FIG. 5C, the second processing liquid nozzle driving unit 65 (see FIG. 3) is driven, and the second processing liquid nozzle 61 advances from the second retracted position Q2 to the second advanced position P2. For example, the second treatment liquid nozzle 61 moves forward from the second backward position Q2 to the second forward position P2 in 0.5 seconds. During this time, SC1 continues to be discharged from the second processing liquid nozzle 61, and the supply of SC1 to the peripheral edge of the wafer W is started by the advancement of the second processing liquid nozzle 61 to the second advance position P2.

<First treatment liquid nozzle advance step>
Next, as shown in FIG. 5D, the first processing liquid nozzle drive unit 55 (see FIG. 3) is driven, and the first processing liquid nozzle 51 advances from the first retracted position Q1 to the first forward position P1. For example, the first treatment liquid nozzle 51 moves forward from the first reverse position Q1 to the first forward position P1 in 0.5 seconds. During this time, hydrofluoric acid continues to be discharged from the first processing liquid nozzle 51, and the supply of hydrofluoric acid to the peripheral portion of the wafer W is started by the first processing liquid nozzle 51 moving forward to the first advance position P1. To do. In this way, the first process liquid nozzle advance process is performed after the second process liquid nozzle advance process, and after the supply of SC1 to the wafer W is started, hydrofluoric acid is supplied to the wafer W.

<Natural oxide film removal process>
Next, as shown in FIG. 5E, the first processing liquid nozzle 51 is maintained at the first forward position P1 and the second processing liquid nozzle 61 is maintained at the second forward position P2 for a predetermined time. Then, hydrofluoric acid is continuously supplied from the first processing liquid nozzle 51 to the natural oxide film formed on the peripheral edge of the rotating wafer W for a predetermined time. The hydrofluoric acid supply position from the first treatment liquid nozzle 51 located at the first advance position P1 is a position where a region extending from the outer edge to a predetermined width can be removed from the natural oxide film on the wafer W. . As a result, the region of the natural oxide film is removed by etching with hydrofluoric acid, and the surface of the peripheral portion of the wafer W is exposed. For example, hydrofluoric acid continues to be discharged from the first treatment liquid nozzle 51 located at the first advance position P1 for 60 seconds. The hydrofluoric acid discharged to the peripheral edge of the wafer W receives centrifugal force due to the rotation of the wafer W, flows from the position where hydrofluoric acid is supplied to the wafer W to the outer peripheral side, and is discharged from the outer edge of the wafer W. In the natural oxide film removal step, the rotational speed of the wafer W is preferably high to some extent, for example, as described above at 1800 rpm, in order to improve the removal accuracy of the natural oxide film. Thus, centrifugal force can be applied to the hydrofluoric acid supplied to the wafer W, and the hydrofluoric acid on the surface of the wafer W can be prevented from advancing to the inner peripheral side. In this case, the positional accuracy of the outer edge after etching of the natural oxide film remaining on the surface of the wafer W can be improved.

  By the way, the supply position of SC1 from the second processing liquid nozzle 61 located at the second forward movement position P2 is set according to the rotation speed of the wafer W and the discharge amount of hydrofluoric acid from the first processing liquid nozzle 51. . For example, as the rotational speed of the wafer W decreases, the SC1 supply position is preferably closer to the hydrofluoric acid supply position from the first processing liquid nozzle 51 located at the first advance position P1. Further, as the discharge amount of hydrofluoric acid decreases, the SC1 supply position is preferably closer to the hydrofluoric acid supply position. In this way, the second processing liquid nozzle 61 located at the second advance position P2 can supply SC1 to the hydrofluoric acid remaining on the surface of the wafer W and before drying. For this reason, it can suppress that the surface of the wafer W is hydrophobized, and can make the surface of the wafer W hydrophilic by touching SC1. The SC1 discharged to the peripheral edge of the wafer W receives centrifugal force due to the rotation of the wafer W, flows from the supply position of the SC1 to the wafer W to the outer peripheral side, and is discharged from the outer edge of the wafer W.

<First treatment liquid nozzle receding step>
Next, as shown in FIG. 5F, the first processing liquid nozzle driving unit 55 is driven, and the first processing liquid nozzle 51 is moved backward from the first forward position P1 to the first backward position Q1. For example, the first treatment liquid nozzle 51 moves backward from the first forward position P1 to the first backward position Q1 in 0.5 seconds. During this time, hydrofluoric acid continues to be discharged from the first processing liquid nozzle 51, but the supply of hydrofluoric acid to the peripheral edge of the wafer W ends with the retreat of the first processing liquid nozzle 51.

<Second treatment liquid nozzle receding step>
Next, as shown in FIG. 5G, the second processing liquid nozzle drive unit 65 is driven, and the second processing liquid nozzle 61 moves backward from the second forward position P2 to the second backward position Q2. For example, the second processing liquid nozzle 61 moves backward from the second forward position P2 to the second backward position Q2 in 0.5 seconds. During this time, SC1 continues to be discharged from the second processing liquid nozzle 61, but the supply of SC1 to the peripheral edge of the wafer W is completed as the second processing liquid nozzle 61 moves backward. In this way, the second process liquid nozzle retracting process is performed after the first process liquid nozzle retracting process, and after the supply of hydrofluoric acid to the wafer W is completed, the supply of SC1 to the wafer W is terminated. .

<Discharge stop process>
Thereafter, the first processing liquid valve 54 is closed, and the discharge of hydrofluoric acid from the first processing liquid nozzle 51 located at the first retracted position Q1 is stopped. Further, the second processing liquid valve 64 is closed, and the discharge of SC1 from the second processing liquid nozzle 61 located at the second retreat position Q2 is stopped. In this way, the treatment liquid supply process is completed.

[Rinse supply process]
After the processing liquid supply step described above, DIW as a rinsing liquid is supplied to the peripheral portion of the wafer W. In the rinsing liquid supply step, the rotation speed of the wafer W is lowered. Here, for example, the rotation speed of the wafer W is set to 600 rpm.

<Discharge start process>
First, the DIW valve 74 is opened, and DIW is discharged from the DIW nozzle 71 located at the third retracted position Q3 as shown in FIG. 6A. While the DIW nozzle 71 is maintained at the third retracted position Q3, DIW is discharged for a predetermined time. As a result, even if the DIW discharge amount is small, the DIW discharge amount can be stabilized. For example, DIW continues to be discharged at a discharge rate of 15 mL / min for 1 second.

<DIW nozzle advancement process>
Next, as shown in FIG. 6B, the DIW nozzle driving unit 75 is driven, and the DIW nozzle 71 moves forward from the third backward position Q3 to the third forward position P3. For example, the DIW nozzle 71 advances from the third backward position Q3 to the third forward position P3 in 1 second. During this time, DIW continues to be discharged from the DIW nozzle 71, and the DIW nozzle 71 that has advanced to the third forward position P3 starts to supply DIW to the peripheral edge of the wafer W.

<Rinsing process>
Next, as shown in FIG. 6C, the DIW nozzle 71 is maintained at the third forward position P3 for a predetermined time. The third advance position P3 of the DIW nozzle 71 is such that the supply position of DIW to the wafer W is closer to the center O of the wafer W than the supply position of SC1 to the wafer W. As a result, the wafer W is rinsed, and the hydrofluoric acid and SC1 remaining on the surface of the wafer W can be washed away. In the rinsing liquid supply step, since the first processing liquid nozzle 51 and the second processing liquid nozzle 61 are retracted, the third forward position P3 of the DIW nozzle 71 in the circumferential direction is limited to the position shown in FIG. 6C. There is nothing.

  In the rinsing process, DIW is continuously supplied from the DIW nozzle 71 to the peripheral edge of the rotating wafer W for a predetermined time. For example, DIW continues to be ejected from the DIW nozzle 71 located at the third forward position P3 for 15 seconds. The DIW discharged to the peripheral edge of the wafer W receives centrifugal force due to the rotation of the wafer W, flows from the supply position of the DIW to the wafer W to the outer peripheral side, and is discharged from the outer edge of the wafer W.

<DIW nozzle retracting process>
Next, as shown in FIG. 6D, the DIW nozzle driving unit 75 is driven, and the DIW nozzle 71 moves backward from the third forward position P3 to the third backward position Q3. For example, the DIW nozzle 71 moves backward from the third forward position P3 to the third backward position Q3 in 1 second. During this time, DIW continues to be discharged from the DIW nozzle 71, but as the DIW nozzle 71 moves backward, the supply of DIW to the peripheral edge of the wafer W is completed.

<Discharge stop process>
Thereafter, the DIW valve 74 is closed, and the discharge of DIW from the DIW nozzle 71 located at the third reverse position Q3 is stopped. In this way, the rinse liquid supply process is completed.

[Drying process]
After the rinsing liquid supply process described above, the wafer W is dried by increasing the number of rotations of the wafer W as shown in FIG. For example, the rotation speed of the wafer W is set to 2500 rpm. As a result, the DIW remaining on the surface of the wafer W receives centrifugal force due to the rotation of the wafer W, flows from the supply position of the DIW to the wafer W toward the outer periphery, and is discharged from the outer edge of the wafer W. For this reason, DIW is removed from the surface of the wafer W, and the surface of the wafer W is dried.

  As described above, according to the present embodiment, hydrofluoric acid is supplied to the natural oxide film formed on the peripheral portion of the rotating wafer W to remove the natural oxide film, and the hydrofluoric acid on the surface of the wafer W is also removed. SC1 is supplied. Thus, before the hydrofluoric acid on the surface of the wafer W is dried, SC1 can be supplied to the hydrofluoric acid remaining on the surface, and the surface of the wafer W can be hydrophilized. That is, it is possible to suppress the hydrofluoric acid on the surface of the wafer W from being dried and making the surface hydrophobic. For this reason, it can suppress that hydrofluoric acid and SC1 supplied to the peripheral part of the wafer W scatter to an inner peripheral side, and can suppress that a particle source is formed. As a result, generation of particles at the peripheral edge of the wafer W can be suppressed.

  Further, according to the present embodiment, the supply position of SC1 to the surface of wafer W is closer to the center O of the surface of wafer W than the supply position of hydrofluoric acid to the surface of wafer W. Thus, SC1 can be supplied to a region on the inner peripheral side of hydrofluoric acid in the radial direction of the wafer W. For this reason, it can suppress that SC1 is no longer supplied to the hydrofluoric acid supplied to the surface of the wafer W, and can further suppress that the hydrofluoric acid on the surface of the wafer W dries out, and the surface is further improved. It can be made hydrophilic.

  Further, according to the present embodiment, hydrofluoric acid is supplied to the surface of the wafer W after the supply of SC1 to the surface of the wafer W is started. This can prevent hydrofluoric acid from being supplied before SC1 is supplied to the surface of the wafer W. For this reason, it can suppress further that the hydrofluoric acid on the surface of the wafer W dries, and can make the surface further hydrophilic.

  Further, according to the present embodiment, after the supply of hydrofluoric acid to the surface of wafer W is completed, the supply of SC1 to wafer W is completed. This can prevent SC1 from being supplied to the hydrofluoric acid supplied to the surface of the wafer W. For this reason, it can suppress further that the hydrofluoric acid on the surface of the wafer W dries, and can make the surface further hydrophilic.

  Furthermore, according to the present embodiment, SC1 is supplied to hydrofluoric acid on the surface of wafer W. Thus, the surface of the wafer W exposed by removing the natural oxide film can be hydrophilized by SC1. Further, since the viscosity of SC1 is low, the discharge amount can be stabilized even if the discharge amount from the second processing liquid nozzle 61 is reduced in order to supply SC1 to a limited region called the peripheral portion of the wafer W. it can. Furthermore, since SC1 has a low viscosity, it can be easily washed away by DIW and has low toxicity. For this reason, the handleability of a 2nd process liquid can be improved.

  In the above-described embodiment, an example in which hydrofluoric acid is used as the first processing liquid for hydrophobizing the surface of the wafer W has been described. However, the present invention is not limited to this, and the first treatment liquid may be, for example, a dilute hydrofluoric acid aqueous solution (DHF) that is an aqueous solution containing hydrofluoric acid.

  In the above-described embodiment, the example in which SC1 is used as the second processing liquid supplied to the hydrofluoric acid on the surface of the wafer W has been described. However, the second treatment liquid is not limited to this, and may be any liquid that has an oxidizing power and does not have an etching action on the silicon wafer W. For example, nitric acid or sulfuric acid Etc. can also be used. Alternatively, DIW can be used as the second treatment liquid. In this case, before the hydrofluoric acid on the surface of the wafer W is dried, DIW can be supplied to the hydrofluoric acid remaining on the surface, and the surface of the wafer W can be prevented from drying. For this reason, it can suppress that hydrofluoric acid and SC1 supplied to the peripheral part of the wafer W scatter to an inner peripheral side, and can suppress that a particle source is formed. Further, DIW is weaker than SC1, but has an oxidizing power, so that the surface of the wafer W can be made hydrophilic. When DIW is used for the second processing liquid, after the first processing liquid nozzle retreating process, the second processing liquid nozzle 61 is not retreated, and the DIW is continuously supplied and maintained at the second advance position P2. The rinsing liquid supply process can also be performed, and the process can be simplified. As the second treatment liquid, ozone water can be used instead of DIW.

  Furthermore, in the present embodiment described above, DIW may be supplied to the peripheral portion of the wafer W as shown in FIG.

  In this case, for example, in the discharge start process of the process liquid supply process, DIW is discharged from the DIW nozzle 71, and before the second process liquid nozzle advance process, the DIW nozzle 71 is moved from the third retracted position Q3 to the third advance position P3. Move forward. During this time, DIW is continuously discharged from the DIW nozzle 71. As a result, the hydrofluoric acid discharged from the first processing liquid nozzle 51 can be supplied to the DIW liquid film supplied onto the surface of the wafer W, and the hydrofluoric acid supplied to the peripheral portion of the wafer W can be reduced. It is possible to suppress scattering to the inner peripheral side and to prevent the particle source from being formed. As shown in FIG. 8, it is preferable that the DIW supply position is arranged in the vicinity of the upstream side in the rotation direction of the wafer W with respect to the hydrofluoric acid supply position in plan view.

  Then, after the second treatment liquid nozzle retreating step, the rinsing liquid supply step can be performed by maintaining the third advance position P3 and continuing to supply DIW without retreating the DIW nozzle 71. It can be simplified.

  The present invention is not limited to the above-described embodiments and modifications as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments and modifications. You may delete a some component from all the components shown by embodiment and a modification. Furthermore, constituent elements over different embodiments and modifications may be combined as appropriate.

18 Control unit 30 Substrate processing apparatus 31 Holding unit 33 Rotation driving unit 50 First processing liquid supply unit 51 First processing liquid nozzle 55 First processing liquid nozzle driving unit 60 Second processing liquid supply unit 61 Second processing liquid nozzle 65 First 2 treatment liquid nozzle drive unit 70 DIW supply unit 71 DIW nozzle P1 first forward position P2 second forward position Q1 first backward position Q2 second backward position W wafer

Claims (14)

A substrate processing method for removing a film formed on a peripheral portion of a substrate,
Holding step for holding the substrate horizontally;
A rotation start step for starting rotation of the held substrate;
A first treatment liquid containing hydrofluoric acid for hydrophobizing the substrate is supplied to the film formed on the peripheral edge of the rotating substrate to remove the film, and the first treatment on the substrate. A substrate processing method comprising: a processing liquid supply step for supplying a second processing liquid for hydrophilizing the substrate to the liquid.   2. The substrate according to claim 1, wherein, in the treatment liquid supply step, a supply position of the second treatment liquid to the substrate is closer to a center of the substrate than a supply position of the first treatment liquid to the substrate. Processing method.   3. The substrate processing method according to claim 1, wherein, in the processing liquid supply step, the first processing liquid is supplied to the substrate after the supply of the second processing liquid to the substrate is started.   The said process liquid supply process WHEREIN: After ending supply of the said 1st process liquid to the said board | substrate, supply of the said 2nd process liquid to the said board | substrate is complete | finished. Substrate processing method.   5. The substrate processing method according to claim 1, wherein DIW is supplied to the peripheral portion of the substrate in the processing liquid supply step.   The substrate processing method according to claim 1, wherein the second processing liquid includes SC1.   When executed by a computer for controlling the operation of the substrate processing apparatus, the computer controls the substrate processing apparatus to execute the substrate processing method according to any one of claims 1 to 6. A storage medium on which a program is recorded. A substrate processing apparatus for removing a film formed on a peripheral portion of a substrate,
A holding unit for holding the substrate horizontally;
A rotation drive unit for rotating the holding unit;
A first processing liquid supply including a first processing liquid nozzle that supplies a first processing liquid containing hydrofluoric acid that hydrophobizes the substrate to the film formed on the peripheral edge of the substrate held by the holding unit. And
A second processing liquid supply unit including a second processing liquid nozzle for supplying a second processing liquid for hydrophilizing the substrate to the first processing liquid on the substrate;
A control unit,
The control unit drives the rotation driving unit to start rotation of the substrate held by the holding unit, and then supplies the first processing liquid from the first processing liquid nozzle to the rotating substrate. A substrate processing apparatus for controlling the rotation drive unit, the first processing liquid supply unit, and the second processing liquid supply unit so that the second processing liquid is supplied from the second processing liquid nozzle.   The supply position of the second treatment liquid from the second treatment liquid nozzle to the substrate is closer to the center of the substrate than the supply position of the first treatment liquid from the first treatment liquid nozzle to the substrate, The substrate processing apparatus according to claim 8.   The controller is configured to supply the first processing liquid from the first processing liquid nozzle to the substrate after starting the supply of the second processing liquid from the second processing liquid nozzle to the substrate. The substrate processing apparatus according to claim 8, wherein the substrate processing apparatus controls the first processing liquid supply unit and the second processing liquid supply unit.   The control unit finishes the supply of the second processing liquid from the second processing liquid nozzle to the substrate after finishing the supply of the first processing liquid from the first processing liquid nozzle to the substrate. The substrate processing apparatus according to claim 8, wherein the first processing liquid supply unit and the second processing liquid supply unit are controlled. A first processing liquid nozzle driving unit for moving the first processing liquid nozzle forward and backward between a first forward position for supplying the first processing liquid to the substrate and a first backward position retracted from the substrate;
A second processing liquid nozzle driving unit for moving the second processing liquid nozzle forward and backward between a second forward position for supplying the second processing liquid to the substrate and a second backward position retracted from the substrate; In addition,
The controller advances the second processing liquid nozzle to the second forward position while discharging the second processing liquid, and then moves the first processing liquid nozzle to the first while discharging the first processing liquid. The first processing liquid supply unit, the second processing liquid supply unit, the first processing liquid nozzle driving unit, and the second processing liquid nozzle driving unit are controlled to advance to one advance position. The substrate processing apparatus according to claim 11.   The control unit retreats the first treatment liquid nozzle to the first retracted position while discharging the first treatment liquid, and then moves the second treatment liquid nozzle to the first while discharging the second treatment liquid. 13. The first processing liquid supply unit, the second processing liquid supply unit, the first processing liquid nozzle driving unit, and the second processing liquid nozzle driving unit are controlled so as to be moved back to a retreat position. The substrate processing apparatus as described.   The substrate processing apparatus according to claim 8, further comprising a DIW supply unit including a DIW nozzle that supplies DIW to the peripheral portion of the substrate held by the holding unit.

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