阅读说明：本技术 基板处理装置和基板处理方法 (Substrate processing apparatus and substrate processing method ) 是由 小佐井一树 篠原和义 于 2020-10-23 设计创作，主要内容包括：本发明提供一种基板处理装置和基板处理方法。提供一种能够抑制在对基板处理部进行了清洗处理之后液处理的性能恶化的技术。本公开的一形态的基板处理装置具备基板处理部、排液部以及控制部。基板处理部从处理液供给部向所载置的基板供给处理液而进行液处理。排液部具有与积存处理液的积存部连接的回收路径,对液处理使用后的处理液进行排液。控制部执行液处理的处理制程以及清洗基板处理部和排液部的清洗制程。另外,作为清洗制程,控制部在执行了从清洗液供给部供给清洗液而清洗基板处理部和排液部的清洗动作之后,执行从处理液供给部供给处理液而将附着于基板处理部和排液部的清洗液置换成处理液的恢复动作。(The invention provides a substrate processing apparatus and a substrate processing method. Provided is a technique capable of suppressing deterioration of liquid processing performance after a cleaning process is performed on a substrate processing section. A substrate processing apparatus according to one aspect of the present disclosure includes a substrate processing unit, a liquid discharge unit, and a control unit. The substrate processing unit performs liquid processing by supplying a processing liquid from a processing liquid supply unit to a substrate placed thereon. The liquid discharge unit has a recovery path connected to a reservoir for storing the treatment liquid, and discharges the treatment liquid used for liquid treatment. The control unit executes a treatment process for treating the liquid and a cleaning process for cleaning the substrate treating unit and the liquid discharge unit. In addition, as the cleaning process, the control unit performs a cleaning operation of supplying the cleaning liquid from the cleaning liquid supply unit to clean the substrate processing unit and the liquid discharge unit, and then performs a recovery operation of supplying the processing liquid from the processing liquid supply unit to replace the cleaning liquid adhering to the substrate processing unit and the liquid discharge unit with the processing liquid.)

1. A substrate processing apparatus, wherein,

the substrate processing apparatus includes:

a substrate processing unit for performing liquid processing by supplying a processing liquid from a processing liquid supply unit to a substrate placed thereon;

a liquid discharge unit having a recovery path connected to a reservoir for storing the treatment liquid, and discharging the treatment liquid used for the liquid treatment; and

a control unit for executing a treatment process of the liquid treatment and a cleaning process of cleaning the substrate treatment unit and the liquid discharge unit,

in the cleaning process, the control unit performs a cleaning operation of supplying a cleaning liquid from a cleaning liquid supply unit to clean the substrate processing unit and the liquid discharge unit, and then performs a recovery operation of supplying the processing liquid from the processing liquid supply unit to replace the cleaning liquid adhering to the substrate processing unit and the liquid discharge unit with the processing liquid.

2. The substrate processing apparatus according to claim 1,

the treatment process includes a treatment order of the substrate and a kind of the treatment liquid.

3. The substrate processing apparatus according to claim 2,

the cleaning process is selected based on the type of the treatment liquid included in the treatment process.

4. The substrate processing apparatus according to claim 3,

the cleaning process is selected based on the treatment process subsequent to the cleaning process.

5. The substrate processing apparatus according to any one of claims 1 to 4,

the liquid discharge portion has a discharge portion that discharges the processing liquid to the outside,

the control unit discharges the drain liquid flowing to the drain unit to the outside from the drain unit while the cleaning process is being performed.

6. The substrate processing apparatus according to any one of claims 1 to 5,

the liquid discharge portion has a concentration sensor that detects a concentration of the processing liquid,

the control unit terminates the recovery operation based on the concentration of the processing liquid detected by the concentration sensor.

7. The substrate processing apparatus according to any one of claims 1 to 6,

the substrate processing apparatus includes a gas supply unit for supplying a gas to the substrate processing unit and the liquid discharge unit,

the control unit performs a gas purge operation of supplying the gas to purge the cleaning liquid adhering to the substrate processing unit and the liquid discharge unit after performing the cleaning operation.

8. The substrate processing apparatus according to claim 7,

the control unit supplies the gas to a portion where the cleaning liquid is retained as the gas purge operation.

9. The substrate processing apparatus according to any one of claims 1 to 8,

the substrate processing apparatus includes a standby unit for the processing liquid supply unit to stand by,

the liquid discharge path of the standby part is connected with the liquid discharge path of the liquid discharge part,

the control unit executes the same cleaning process as the substrate processing unit for the standby unit.

10. The substrate processing apparatus according to any one of claims 1 to 9,

the substrate processing apparatus includes a back surface supply unit for discharging the processing liquid to the back surface side of the substrate,

the control unit executes the cleaning process on the back supply unit.

11. A method for processing a substrate, wherein,

the substrate processing method includes the steps of:

a liquid treatment step of performing a treatment process including: supplying a processing liquid from a processing liquid supply unit to a substrate placed on a substrate processing unit, and collecting the used processing liquid from a drain unit to a reservoir; and

a cleaning step of performing a cleaning process of: cleaning the processing liquid adhering to the substrate processing section and the liquid discharge section in the liquid processing step,

the cleaning step includes a cleaning operation of supplying a cleaning liquid to clean the substrate processing section and the liquid discharge section, and a recovery operation of supplying the processing liquid to replace the cleaning liquid adhering to the substrate processing section and the liquid discharge section with the processing liquid.

Technical Field

The disclosed embodiments relate to a substrate processing apparatus and a substrate processing method.

Background

Conventionally, a technique of subjecting a substrate such as a semiconductor wafer (hereinafter, also referred to as a wafer) to liquid treatment using BHF (buffered hydrofluoric acid) in a single-substrate treatment section has been known (see patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2014-41994

Disclosure of Invention

Problems to be solved by the invention

The present disclosure provides a technique capable of suppressing deterioration of performance of liquid processing after a cleaning process is performed on a substrate processing section.

Means for solving the problems

A substrate processing apparatus according to one aspect of the present disclosure includes a substrate processing unit, a liquid discharge unit, and a control unit. The substrate processing unit performs liquid processing by supplying a processing liquid from a processing liquid supply unit to a substrate placed thereon. The liquid discharge unit has a recovery path connected to a reservoir for storing the treatment liquid, and discharges the treatment liquid used for the liquid treatment. The control unit executes a treatment process of the liquid treatment and a cleaning process of cleaning the substrate treatment unit and the liquid discharge unit. In the cleaning process, the control unit may perform a cleaning operation of supplying a cleaning liquid from a cleaning liquid supply unit to clean the substrate processing unit and the liquid discharge unit, and then perform a recovery operation of supplying the processing liquid from the processing liquid supply unit to replace the cleaning liquid adhering to the substrate processing unit and the liquid discharge unit with the processing liquid.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present disclosure, it is possible to suppress deterioration of the performance of the liquid treatment after the cleaning treatment is performed on the substrate treatment section.

Drawings

Fig. 1 is a schematic diagram showing a schematic configuration of a substrate processing system according to an embodiment.

Fig. 2 is a schematic diagram showing a configuration example of a processing unit according to the embodiment.

Fig. 3 is a schematic view showing a piping structure of the substrate processing system according to the embodiment.

Fig. 4 is a schematic diagram showing a piping structure of the reservoir according to the embodiment.

Fig. 5 is a diagram for explaining a flow of processing in the substrate processing system according to the embodiment.

Fig. 6A is a diagram (1) showing an operation example of the cleaning operation and the recovery operation according to the embodiment.

Fig. 6B is a diagram (2) showing an operation example of the cleaning operation and the recovery operation according to the embodiment.

Fig. 6C is a diagram (fig. 3) showing an operation example of the cleaning operation and the recovery operation according to the embodiment.

Fig. 6D is a diagram (4) showing an operation example of the cleaning operation and the recovery operation according to the embodiment.

Fig. 6E is a diagram (fig. 5) showing an operation example of the cleaning operation and the recovery operation according to the embodiment.

Fig. 6F is a diagram (fig. 6) showing an operation example of the cleaning operation and the recovery operation according to the embodiment.

Fig. 6G is a diagram (fig. 7) showing an operation example of the cleaning operation and the recovery operation according to the embodiment.

Fig. 7 is a diagram showing a relationship between the time of the recovery operation and the amount of change in the etching rate in the subsequent processing step in the embodiment.

Fig. 8 is a diagram for explaining a flow of processing in the substrate processing system according to modification 1 of the embodiment.

Fig. 9 is a diagram for explaining a flow of processing in the substrate processing system according to modification 2 of the embodiment.

Fig. 10 is a flowchart showing a procedure of substrate processing performed by the substrate processing system according to the embodiment.

Description of the reference numerals

W, wafer (an example of a substrate); 1. a substrate processing system (an example of a substrate processing apparatus); 16. a processing unit; 18. a control unit; 30. a substrate processing unit; 41a to 41c, and a nozzle (an example of a treatment liquid supply unit); 50. a liquid discharge section; 59a to 59c, a liquid discharge path; 62a to 62c, a concentration sensor; 64a to 64c, a recovery path; 65a to 65c, a standby part; 70a to 70c, a reservoir; s1, S1a, S1b, and a treatment process; s2, a cleaning process; s3, cleaning; s4, restoring the action; and S5, performing gas purging.

Detailed Description

Hereinafter, embodiments of the substrate processing apparatus and the substrate processing method disclosed in the present application will be described in detail with reference to the drawings. The present disclosure is not limited to the embodiments described below. Note that the drawings are schematic, and the relationship between the sizes of the elements, the ratio of the elements, and the like may be different from those in reality. Also, there are cases where: the drawings also include portions having different dimensional relationships and proportions from each other.

Conventionally, a technique of performing liquid processing on a substrate such as a semiconductor wafer (hereinafter, also referred to as a wafer) by using BHF (buffered hydrofluoric acid) in a single-substrate processing unit is known. Further, BHF is HF (hydrofluoric acid) and NH₄F (ammonium fluoride).

In the liquid treatment by this BHF, the following problems may occur: BHF scattered during liquid processing and adhering to the substrate processing portion is crystallized, and the crystals adhere to the wafer as fine particles. Therefore, the crystallized BHF is periodically cleaned with a cleaning liquid such as DIW (deionized water), and the adhesion of particles due to BHF to the wafer is suppressed.

Further, BHF is a relatively expensive chemical solution, and therefore, there are cases where: the BHF used once for the liquid treatment is collected from the drainage portion into the reservoir, and the used BHF is reused for the liquid treatment.

However, since the cleaning liquid (DIW) adheres to and remains in the substrate processing portion and the drain portion after the cleaning process, the BHF concentration may be lowered when the BHF is collected into the reservoir portion together with the DIW. Further, when the concentration of BHF is decreased, the performance of the fluid treatment by BHF may be deteriorated.

Therefore, the following techniques are expected: the above-described problems can be overcome, and deterioration in performance of liquid treatment after the cleaning treatment is performed on the substrate treatment unit can be suppressed.

< overview of substrate processing System >

First, a schematic configuration of the substrate processing system 1 according to the embodiment will be described with reference to fig. 1. Fig. 1 is a diagram showing a schematic configuration of a substrate processing system 1 according to an embodiment. The substrate processing system 1 is an example of a substrate processing apparatus. Hereinafter, in order to clarify the positional relationship, an X axis, a Y axis, and a Z axis orthogonal to each other are defined, and the positive Z axis direction is set to be the vertically upward direction.

As shown in fig. 1, the substrate processing system 1 includes a loading/unloading station 2 and a processing station 3. The in-and-out station 2 is disposed adjacent to the processing station 3.

The carry-in/out station 2 includes a carrier placement unit 11 and a transport unit 12. A plurality of carriers C, which accommodate a plurality of substrates, in the embodiment, semiconductor wafers W (hereinafter referred to as wafers 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 transfer unit 14. The substrate transfer device 13 includes a wafer holding mechanism for holding the wafer W. The substrate transfer device 13 is movable in the horizontal direction and the vertical direction and rotatable about the vertical axis, and the substrate transfer device 13 transfers the wafer W between the carrier C and the transfer portion 14 by using the wafer holding mechanism.

The processing station 3 is disposed adjacent to the conveying section 12. The processing station 3 includes a conveying unit 15 and a plurality of processing units 16. The plurality of processing units 16 are arranged on both sides of the conveying unit 15.

The conveying unit 15 is internally provided with a substrate conveying device 17. The substrate transfer device 17 includes a wafer holding mechanism for holding the wafer W. The substrate transfer device 17 is movable in the horizontal direction and the vertical direction and rotatable about the vertical axis, and the substrate transfer device 17 transfers the wafer W between the interface 14 and the processing unit 16 using the wafer holding mechanism.

The processing unit 16 performs a predetermined substrate process on the wafer W conveyed by the substrate conveyor 17.

The substrate processing system 1 further includes a control device 4. The control device 4 is, for example, a computer, and includes a control unit 18 and a storage unit 19. The storage unit 19 stores a program for controlling various processes to be executed in the substrate processing system 1. The control unit 18 reads and executes the program stored in the storage unit 19 to control the operation of the substrate processing system 1.

The program may be a program recorded on a computer-readable storage medium, or may be a program loaded from the storage medium into the storage unit 19 of the control device 4. As a storage medium that can be read by a computer, there are, for example, a Hard Disk (HD), a Flexible Disk (FD), an optical disk (CD), a magneto-optical disk (MO), a memory card, and the like.

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

The wafer W sent into the processing unit 16 is processed by the processing unit 16, and then sent out from the processing unit 16 by the substrate transfer device 17 to be placed on the delivery part 14. Then, the processed wafer W placed on the transfer portion 14 is returned to the carrier C of the carrier placing portion 11 by the substrate transport apparatus 13.

< Structure of processing Unit >

Next, the structure of the processing unit 16 will be described with reference to fig. 2. Fig. 2 is a schematic diagram showing a specific configuration example of the processing unit 16. As shown in fig. 2, the processing unit 16 includes a chamber 20, a substrate processing unit 30, a liquid supply unit 40, and a liquid discharge unit 50.

The chamber 20 accommodates at least a part of the substrate processing unit 30, the liquid supply unit 40, and the liquid discharge unit 50. A FFU (Fan Filter Unit)21 is provided at the top of the chamber 20. FFU21 forms a downward flow within chamber 20.

FFU21 is connected to downflow gas supply 23 via valve 22. The FFU21 ejects a downflow gas (e.g., dry air) supplied from the downflow gas supply source 23 into the chamber 20.

The substrate processing unit 30 includes a rotation holding unit 31, a column unit 32, and a driving unit 33, and performs liquid processing on the wafer W placed thereon. The rotation holding portion 31 is provided substantially at the center of the chamber 20. A holding member 31a for holding the wafer W from the side surface is provided on the upper surface of the rotation holding portion 31. The wafer W is horizontally held by the holding member 31a in a state slightly separated from the upper surface of the rotation holding portion 31.

The support column portion 32 is a member extending in the vertical direction, and has a base end portion supported rotatably by the drive portion 33 and a distal end portion horizontally supporting the rotation holding portion 31. The driving unit 33 rotates the column portion 32 about the vertical axis.

The substrate processing unit 30 rotates the column part 32 using the driving unit 33, thereby rotating the rotation holding unit 31 supported by the column part 32, and thereby rotating the wafer W held by the rotation holding unit 31.

The liquid supply portion 40 includes a1 st liquid supply portion 40a and a 2 nd liquid supply portion 40 b. The 1 st liquid supply unit 40a supplies various processing liquids to the wafer W held by the substrate processing unit 30. The 1 st liquid supply unit 40a includes nozzles 41a to 41c, an arm 42a for horizontally supporting the nozzles 41a to 41c, and a rotary lifting mechanism 43a for rotating and lifting the arm 42 a.

The nozzles 41a to 41c are examples of the treatment liquid supply unit. The 1 st BHF having the 1 st hydrofluoric acid concentration is discharged from the nozzle 41a toward the surface of the wafer W. The 2 nd BHF having the 2 nd hydrofluoric acid concentration is discharged from the nozzle 41b toward the surface of the wafer W.

The 3 rd BHF having the 3 rd hydrofluoric acid concentration is discharged from the nozzle 41c toward the surface of the wafer W. The 1 st BHF to 3 rd BHF are examples of the treatment liquid. The piping structure of the substrate processing system 1 including the nozzles 41a to 41c will be described later.

The 2 nd liquid supply unit 40b supplies DIW to the wafer W held by the substrate processing unit 30. The 2 nd liquid supply unit 40b includes a nozzle 41d, an arm 42b horizontally supporting the nozzle 41d, and a turning and lifting mechanism 43b for turning and lifting the arm 42 b.

The DIW supplied through a DIW supply path, not shown, is discharged from the nozzle 41d toward the front surface of the wafer W. The DIW is an example of the cleaning liquid, and the nozzle 41d is an example of the cleaning liquid supply portion.

The 1 st and 2 nd rotary cups 34 and 35 that rotate integrally with the rotation holding portion 31 are provided at the peripheral edge portion of the rotation holding portion 31. As shown in fig. 2, the 2 nd rotor 35 is disposed inside the 1 st rotor 34.

The 1 st and 2 nd rotary cups 34 and 35 are formed in an annular shape as a whole. When the 1 st and 2 nd spin cups 34 and 35 are rotated together with the spin holder 31, the 1 st and 2 nd spin cups 34 and 35 guide the processing liquid scattered from the rotating wafer W to the drain 50.

The liquid discharge unit 50 includes a1 st cup 50a, a 2 nd cup 50b, a 3 rd cup 50c, and an antifogging cover 50e in this order from the inside near the rotation center of the wafer W held and rotated by the rotation holding unit 31. The liquid discharge portion 50 further includes a bottom portion 53, an inner wall portion 54d, liquid discharge paths 59a to 59c, and recovery paths 64a to 64c (see fig. 3).

The inner wall portion 54d is disposed on the inner peripheral side of the 1 st cup 50a, and is a cylindrical member centered on the rotation center of the wafer W. The 1 st to 3 rd cups 50a to 50c, the antifogging cover 50e and the inner wall portion 54d are provided on the bottom portion 53 of the liquid discharge portion 50.

The 1 st cup 50a includes a1 st peripheral wall portion 54a and a1 st liquid receiving portion 55 a. The 1 st peripheral wall portion 54a is provided standing from the bottom portion 53, and is formed in a cylindrical shape (for example, a cylindrical shape). A space is formed between the 1 st peripheral wall portion 54a and the inner wall portion 54d, and this space is defined as a1 st drain tank 58a for collecting and discharging the processing liquid and the like. The 1 st liquid receiving portion 55a is provided above the upper surface 54a1 of the 1 st peripheral wall portion 54 a.

The 1 st cup 50a includes a1 st elevation mechanism 56, and the 1 st liquid receiving portion 55a is configured to be able to be elevated by the 1 st elevation mechanism 56. Specifically, the 1 st elevation mechanism 56 includes a1 st support member 56a and a1 st elevation driving unit 56 b.

The 1 st support member 56a is a plurality of (for example, 3, only 1 shown in fig. 2) elongated members. The 1 st support member 56a is movably inserted through a through hole formed in the 1 st peripheral wall portion 54 a. For example, a columnar rod can be used as the 1 st support member 56a, but the present invention is not limited thereto.

The 1 st support member 56a is positioned so that the upper end is exposed from the upper surface 54a1 of the 1 st peripheral wall portion 54a, and is connected to the lower surface of the 1 st liquid receiving portion 55a to support the 1 st liquid receiving portion 55a from below. On the other hand, a1 st elevation drive unit 56b is connected to a lower end of the 1 st support member 56 a.

The 1 st elevation driving portion 56b elevates the 1 st supporting member 56a in, for example, the Z-axis direction, whereby the 1 st supporting member 56a elevates the 1 st liquid receiving portion 55a relative to the 1 st peripheral wall portion 54 a. Further, an air cylinder can be used as the 1 st elevation driving portion 56 b. The 1 st elevation driving unit 56b is controlled by the control device 4.

The 1 st liquid receiving portion 55a driven by the 1 st elevation driving portion 56b moves between a processing position at which the processing liquid scattered from the rotating wafer W is received and a retracted position retracted downward from the processing position.

Specifically, when the 1 st liquid bearing portion 55a is positioned at the processing position, an opening is formed inside the upper end of the 1 st liquid bearing portion 55a, and a flow path leading from the opening to the 1 st drain tank 58a is formed.

On the other hand, as shown in fig. 2, the inner wall portion 54d includes an extended portion 54d1 extending so as to be inclined toward the peripheral edge portion of the rotation holding portion 31. When the 1 st liquid receiving portion 55a is located at the retreat position, it abuts on the extension portion 54d1 of the inner wall portion 54d, and the opening on the inner side of the upper end is closed, thereby closing the flow path leading to the 1 st liquid discharge tank 58 a.

The 2 nd cup 50b has the same structure as the 1 st cup 50 a. Specifically, the 2 nd cup 50b includes a 2 nd peripheral wall portion 54b, a 2 nd liquid receiving portion 55b, and a 2 nd elevating mechanism 57, and the 2 nd cup 50b is disposed adjacent to the 1 st cup 50a on the 1 st peripheral wall portion 54a side of the 1 st cup 50 a.

The 2 nd peripheral wall portion 54b is provided standing on the outer peripheral side of the 1 st peripheral wall portion 54a at the bottom portion 53, and is formed in a cylindrical shape. A space formed between the 2 nd peripheral wall portion 54b and the 1 st peripheral wall portion 54a is a 2 nd drain tank 58b for collecting and discharging the processing liquid and the like.

The 2 nd liquid receiving portion 55b is located on the outer peripheral side of the 1 st liquid receiving portion 55a and is provided above the upper surface 54b1 of the 2 nd peripheral wall portion 54 b.

The 2 nd elevating mechanism 57 includes a 2 nd supporting member 57a and a 2 nd elevating driving portion 57 b. The 2 nd support member 57a is a plurality of (for example, 3 pieces, only 1 piece is shown in fig. 2) elongated members, and is inserted into a through hole formed in the 2 nd peripheral wall portion 54b so as to be movable. For example, a columnar rod can be used as the 2 nd support member 57a, but the present invention is not limited thereto.

The 2 nd support member 57a is positioned so that the upper end is exposed from the upper surface 54b1 of the 2 nd peripheral wall portion 54b, and is connected to the lower surface of the 2 nd liquid receiving portion 55b to support the 2 nd liquid receiving portion 55b from below. The upper surface 54b1 of the 2 nd peripheral wall portion 54b is positioned vertically below the upper surface 54a1 of the 1 st peripheral wall portion 54 a.

A 2 nd elevation driving part 57b is connected to a lower end of the 2 nd supporting member 57 a. The 2 nd elevation driving portion 57b elevates the 2 nd support member 57a in, for example, the Z-axis direction. Thereby, the 2 nd supporting member 57a raises and lowers the 2 nd liquid receiving portion 55b with respect to the 2 nd peripheral wall portion 54 b.

Further, an air cylinder can be used as the 2 nd elevation driving portion 57 b. The 2 nd elevation driving unit 57b is also controlled by the control device 4.

The 2 nd liquid receiving portion 55b also moves between the processing position and the retreat position. Specifically, when the 2 nd liquid receiving portion 55b is located at the processing position and the 1 st liquid receiving portion 55a is located at the retreat position, an opening is formed inside the upper end of the 2 nd liquid receiving portion 55b, and a flow path leading from the opening to the 2 nd drain tank 58b is formed.

On the other hand, as shown in fig. 2, when the 2 nd liquid receiving portion 55b is located at the retreat position, it abuts on the 1 st liquid receiving portion 55a, the opening on the inner side of the upper end is closed, and the flow path leading to the 2 nd drain groove 58b is closed. In the above description, the 2 nd liquid receiving portion 55b at the retracted position abuts on the 1 st liquid receiving portion 55a, but the present invention is not limited to this, and for example, the opening on the inner side of the upper end may be closed by abutting on the inner wall portion 54 d.

The 3 rd cup 50c includes a 3 rd peripheral wall portion 54c and a 3 rd liquid receiving portion 55c, and the 3 rd cup 50c is disposed adjacent to the 2 nd cup 50b on the opposite side of the 1 st cup 50 a. The 3 rd peripheral wall portion 54c is provided standing on the outer peripheral side of the 2 nd peripheral wall portion 54b at the bottom portion 53, and is formed in a cylindrical shape. A space between the 3 rd peripheral wall portion 54c and the 2 nd peripheral wall portion 54b is a 3 rd drain tank 58c for collecting and discharging the processing liquid and the like.

The 3 rd liquid receiving portion 55c is formed continuously with the upper end of the 3 rd peripheral wall portion 54 c. The 3 rd liquid receiving portion 55c is formed so as to surround the periphery of the wafer W held by the rotation holding portion 31 and extend above the 1 st and 2 nd liquid receiving portions 55a and 55 b.

As shown in FIG. 2, the 3 rd liquid receiving portion 55c has an opening formed inside the upper end of the 3 rd liquid receiving portion 55c when both the 1 st liquid receiving portion 55a and the 2 nd liquid receiving portion 55b are located at the retreat position, and forms a flow path leading from the opening to the 3 rd liquid discharge tank 58 c.

On the other hand, when the 2 nd liquid receiving portion 55b is located at the raised position, or when both the 1 st liquid receiving portion 55a and the 2 nd liquid receiving portion 55b are located at the raised position, the 3 rd liquid receiving portion 55c abuts on the 2 nd liquid receiving portion 55b, the opening on the inner side of the upper end is closed, and the flow path leading to the 3 rd liquid discharge tank 58c is closed.

The liquid discharge ports 51a to 51c are formed in the bottom portion 53 at positions corresponding to the 1 st to 3 rd cups 50a to 50c, more specifically, in the bottom portion 53 at positions corresponding to the 1 st to 3 rd liquid discharge grooves 58a to 58c, respectively, with a space therebetween in the circumferential direction of the liquid discharge portion 50.

The drain port 51a is connected to the drain path 59a, the drain port 51b is connected to the drain path 59b, and the drain port 51c is connected to the drain path 59 c. The piping structure of the substrate processing system 1 including the liquid discharge paths 59a to 59c will be described later.

When the substrate processing system 1 performs the substrate processing, the 1 st liquid receiving portion 55a of the 1 st cup 50a and the 2 nd liquid receiving portion 55b of the 2 nd cup 50b are moved up and down according to the kind of the processing liquid used in each of the substrate processing, and the liquid discharge ports 51a to 51c are switched.

For example, when the 1 st BHF is ejected onto the wafer W to process the wafer W, the controller 4 raises the 1 st cup 50a and the 2 nd cup 50 b. That is, the controller 4 raises the 1 st support member 56a and the 2 nd support member 57a via the 1 st elevation driving unit 56b and the 2 nd elevation driving unit 57b, and raises the 1 st liquid receiving unit 55a to the processing position, thereby forming a flow path leading from an opening inside the upper end of the 1 st liquid receiving unit 55a to the 1 st liquid discharge tank 58 a.

Thereby, the 1 st BHF supplied to the wafer W flows into the 1 st drain tank 58 a.

For example, when the 2 nd BHF is discharged to the wafer W and the wafer W is processed, the controller 4 raises only the 2 nd cup 50 b. That is, the controller 4 raises the 2 nd supporting member 57a via the 2 nd elevation driving unit 57b and raises the 2 nd liquid receiving unit 55b to the processing position, thereby forming a flow path leading from the opening on the inside of the upper end of the 2 nd liquid receiving unit 55b to the 2 nd liquid discharge tank 58 b.

Here, the 1 st cup 50a is in a descending state. Thereby, the 2 nd BHF supplied to the wafer W flows into the 2 nd drain tank 58 b.

For example, when the 3 rd BHF is discharged to the wafer W and the wafer W is processed, the controller 4 lowers the 1 st cup 50a and the 2 nd cup 50b (see fig. 2). That is, the controller 4 lowers the 1 st and 2 nd support members 56a and 57a and lowers the 1 st and 2 nd liquid receiving portions 55a and 55b to the retracted positions by the 1 st and 2 nd elevation drive portions 56b and 57 b.

In this way, a flow path leading from the opening on the inside of the upper end of the 3 rd liquid receiving portion 55c to the 3 rd liquid discharge groove 58c is formed. Thereby, the 3 rd BHF supplied to the wafer W flows into the 3 rd drain tank 58 c.

The antifogging cover 50e includes an outer peripheral tube portion 50e1 and an extension portion 50e2 extending from an upper end portion of the outer peripheral tube portion 50e1 toward the inside (in the radial direction) of the outer peripheral tube portion 54e and extending above the 3 rd cup 50 c. The antifogging cover 50e is configured to be movable up and down by an unshown lifting mechanism.

The control unit 18 (see fig. 1) can prevent the mist of the processing liquid scattered from the rotating wafer W from reaching the side wall of the chamber 20 by disposing the anti-mist cover 50e at a high position.

The bottom 53, the 1 st peripheral wall 54a, and the 2 nd peripheral wall 54b of the drain 50 are formed with exhaust ports 52a, 52b, and 52c, respectively. Further, the exhaust ports 52a, 52b, and 52c are connected to 1 exhaust pipe 60, and a valve 61 is interposed between the exhaust pipes 60. The atmosphere in the chamber 20 is exhausted through the exhaust ports 52a, 52b, and 52c and the exhaust pipe 60.

< piping structure of substrate processing System >

Next, the piping structure of the substrate processing system 1 will be described with reference to fig. 3 and 4. Fig. 3 is a schematic view showing a piping structure of the substrate processing system 1 according to the embodiment.

As shown in fig. 3, the drain path 59a connected to the drain port 51a (see fig. 2) of the processing unit 16 is connected to the switching valve 63a via the concentration sensor 62 a. The concentration sensor 62a can detect the concentration of hydrofluoric acid in the liquid flowing through the liquid discharge path 59 a.

The switching valve 63a is connected to a drain DR and a recovery path 64 a. The switching valve 63a is configured to be able to switch the pipe connected to the liquid discharge path 59a to the drain DR or the recovery path 64 a. The control unit 18 (see fig. 1) can switch the discharge path of the waste liquid flowing through the waste liquid path 59a to the discharge portion DR or the collection path 64a by controlling the switching valve 63 a.

The recovery path 64a is connected to a reservoir 70a for storing the 1 st BHF. That is, the controller 18 controls the switching valve 63a to communicate the drain path 59a with the collection path 64a, thereby collecting the 1 st BHF used by the processing unit 16 into the storage unit 70 a.

A supply passage 44a is connected to the reservoir 70a, and the supply passage 44a is connected to the nozzle 41a via a valve 45a and a flow rate adjuster 46 a. Thus, the controller 18 can discharge the 1 st BHF accumulated in the pool portion 70a from the nozzle 41a toward the wafer W. The reservoir 70a will be described in detail later.

Further, a standby portion 65a is provided below the standby position of the nozzle 41a in the chamber 20. The standby unit 65a receives the 1 st BHF discharged from the nozzle 41a during the dummy dispensing process for the purpose of removing air bubbles, foreign matter, and the like in each flow path connected to the nozzle 41a, and discharges the received 1 st BHF to the upstream side of the concentration sensor 62a in the liquid discharge path 59 a. That is, the drain path of the standby unit 65a is connected to the drain path 59 a.

The drain path 59b connected to the drain port 51b (see fig. 2) of the processing unit 16 is connected to the switching valve 63b via the concentration sensor 62 b. The concentration sensor 62b can detect the concentration of hydrofluoric acid in the liquid flowing through the liquid discharge path 59 b.

The switching valve 63b is connected to a drain DR and a recovery path 64 b. The switching valve 63b is configured to be able to switch the pipe connected to the drainage path 59b to the drain DR or the collection path 64 b. The control unit 18 can switch the discharge path of the waste liquid flowing through the waste liquid path 59b to the discharge portion DR or the collection path 64b by controlling the switching valve 63 b.

The recovery path 64b is connected to a reservoir 70b for storing the 2 nd BHF. That is, the controller 18 controls the switching valve 63b to communicate the drain path 59b with the collection path 64b, thereby collecting the 2 nd BHF used by the processing unit 16 into the storage unit 70 b.

The reservoir 70b is connected to a supply path 44b, and the supply path 44b is connected to the nozzle 41b via a valve 45b and a flow rate adjuster 46 b. Thus, the controller 18 can discharge the 2 nd BHF accumulated in the pool portion 70b from the nozzle 41b toward the wafer W.

Further, a standby portion 65b is provided below the standby position of the nozzle 41b in the chamber 20. The standby unit 65b receives the 2 nd BHF discharged from the nozzle 41b during the dummy dispensing process for the purpose of removing air bubbles, foreign substances, and the like in each flow path connected to the nozzle 41b, and discharges the received 2 nd BHF to the upstream side of the concentration sensor 62b in the liquid discharge path 59 b. That is, the drain path of the standby unit 65b is connected to the drain path 59 b.

The drain path 59c connected to the drain port 51c (see fig. 2) of the processing unit 16 is connected to the switching valve 63c via the concentration sensor 62 c. The concentration sensor 62c can detect the concentration of hydrofluoric acid in the liquid flowing through the liquid discharge path 59 c.

The switching valve 63c is connected to a drain DR and a recovery path 64 c. The switching valve 63c is configured to be able to switch the pipe connected to the liquid discharge path 59c to the drain DR or the collection path 64 c. The control unit 18 can switch the discharge path of the waste liquid flowing through the waste liquid path 59c to the discharge portion DR or the collection path 64c by controlling the switching valve 63 c.

The collection path 64c is connected to a reservoir 70c for storing the 3 rd BHF. That is, the controller 18 controls the switching valve 63c to communicate the drain path 59c with the collection path 64c, thereby collecting the 3 rd BHF used by the processing unit 16 into the storage unit 70 c.

A supply passage 44c is connected to the reservoir 70c, and the supply passage 44c is connected to the nozzle 41c via a valve 45c and a flow rate adjuster 46 c. Thus, the controller 18 can discharge the 3 rd BHF accumulated in the pool portion 70c from the nozzle 41c toward the wafer W.

Further, a standby portion 65c is provided below the standby position of the nozzle 41c in the chamber 20. The standby unit 65c receives the 3 rd BHF discharged from the nozzle 41c during the dummy dispensing process for the purpose of removing air bubbles, foreign substances, and the like in each flow path connected to the nozzle 41c, and discharges the received 3 rd BHF to the upstream side of the concentration sensor 62c in the liquid discharge path 59 c. That is, the drain path of the standby unit 65c is connected to the drain path 59 c.

Fig. 4 is a schematic diagram showing a piping structure of the reservoir 70a according to the embodiment. The piping configuration of the reservoir 70b and the piping configuration of the reservoir 70c are the same as those of the reservoir 70a described below, and therefore, the piping configuration of the reservoir 70b and the piping configuration of the reservoir 70c are not described.

The reservoir 70a includes a BHF supply path 71a, a tank 74a, and a circulation path 75 a. The BHF supply path 71a supplies the unused 1 st BHF to the canister 74 a.

The BHF supply path 71a has a BHF supply source 72a and a valve 73a in this order from the upstream side. The BHF supply source 72a is, for example, a tank for storing unused 1 st BHF.

The tank 74a accumulates the 1 st BHF supplied from the BHF supply path 71 a. The tank 74a stores the used 1 st BHF collected through the drainage path 59a and the collection path 64 a.

The circulation path 75a is a circulation path from the tank 74a and back to the tank 74 a. In the circulation path 75a, a pump 76a, a filter 77a, a heater 78a, a valve 79a, a switching valve 80a, a concentration sensor 81a, and a switching valve 82a are provided in this order from the upstream side with respect to the tank 74 a.

The pump 76a forms a circulating flow of the 1 st BHF out of the tank 74a, through the circulation path 75a, and back to the tank 74 a. The filter 77a removes contaminants such as particulates contained in the 1 st BHF circulating in the circulation path 75 a.

The heater 78a heats the 1 st BHF circulating in the circulation path 75 a. The concentration sensor 81a can detect the concentration of hydrofluoric acid in the 1 st BHF flowing through the circulation path 75 a.

Further, a DIW supply source 83a is connected to the upstream side of the switching valve 80a, and the downstream side of the switching valve 82a is connected to the drain DR. The controller 18 (see fig. 1) controls the switching valves 80a and 82a so that the DIW supply source 83a is connected to the drain DR via the concentration sensor 81a, thereby allowing the inside of the concentration sensor 81a to be cleaned by the DIW.

Therefore, according to the embodiment, the concentration sensor 81a can be calibrated by cleaning the inside of the concentration sensor 81a with DIW.

The tank 74a is connected to the drain portion DR via a valve 84a, and the circulation path 75a is connected to the drain portion DR via a valve 85 a. Thus, the control unit 18 can control the valves 84a and 85a to discharge the 1 st BHF in the tank 74a and the circulation path 75a to the discharge portion DR when replacing the 1 st BHF in the tank 74a and the circulation path 75 a.

In addition, the supply path 44a branches off from a portion of the circulation path 75a located between the heater 78a and the valve 79 a. The supply path 44a is interposed between the circulation path 75a and the nozzle 41a (see fig. 3), and supplies the 1 st BHF subjected to the filtration process and the temperature adjustment process in the circulation path 75a to the processing unit 16.

< substrate treatment >

Next, the details of each process in the substrate processing system 1 according to the embodiment will be described with reference to fig. 5 to 7. Fig. 5 is a diagram for explaining a flow of processing in the substrate processing system 1 according to the embodiment.

As shown in fig. 5, in the substrate processing system 1 of the embodiment, the liquid treatment using any one of the 1 st BHF to the 3 rd BHF is continuously performed on the wafer W in the processing unit 16 in the processing step S1 corresponding to the BHF used.

The processing process S1 according to the embodiment includes the processing procedure of the wafer W and the type of the processing liquid, and is stored in the storage unit 19 (see fig. 1) in advance. That is, the processing steps S1 according to the embodiments are prepared for different kinds of BHFs. This enables the processing unit 16 to perform the liquid processing optimized for each of the different kinds of BHFs.

In the example of fig. 5, the treatment process S1 of the liquid treatment performed before the target cleaning process S2 is referred to as a treatment process S1a, and the treatment process S1 of the liquid treatment performed after the target cleaning process S2 is referred to as a treatment process S1 b.

In the substrate processing system 1, the cleaning process S2 is performed in the processing unit 16 intermittently in the repeated processing process S1. The cleaning process S2 includes a cleaning action S3 and a recovery action S4.

The cleaning operation S3 is to clean the substrate processing unit 30 and the drain unit 50 by supplying DIW as a cleaning liquid from the cleaning liquid supply unit (for example, the nozzle 41 d). This makes it possible to remove crystals caused by BHF adhering to the substrate processing portion 30 and the drain portion 50 in the processing step S1a before the cleaning operation S3 is performed.

The recovery operation S4 is, for example, to supply BHF (hereinafter, also referred to as "BHF of subsequent step") used in the subsequent processing step S1b from the processing liquid supply unit (for example, the nozzles 41a to 41c) and replace DIW adhering to the substrate processing unit 30 and the drain unit 50 with BHF of subsequent step.

That is, in the embodiment, in the recovery operation S4, the BHF in the subsequent step is used to pre-wash the DIW remaining in the substrate processing section 30 and the liquid discharge section 50 after the cleaning operation S3. This can prevent the DIW remaining in the substrate processing unit 30 and the drain unit 50 after the cleaning operation S3 from being collected in the accumulating units 70a to 70 c.

Therefore, according to the embodiment, even when the BHF of the subsequent step is subjected to the liquid treatment while being recovered in the subsequent treatment step S1b, the concentration of the recovered BHF can be suppressed from decreasing, and therefore, the performance of the liquid treatment can be suppressed from deteriorating.

In the embodiment, the controller 18 preferably selects the cleaning process S2 based on the treatment process S1. For example, the controller 18 preferably selects the cleaning process S2 based on the type of BHF used in the processing process S1.

Next, details of the cleaning operation S3 and the recovery operation S4 will be described with reference to fig. 6A to 6G. Fig. 6A to 6G are diagrams (1 to 7 thereof) showing operation examples of the cleaning operation and the recovery operation according to the embodiment.

As shown in fig. 6A, the cleaning operation S3 is a process of cleaning the rotary holder 31, the holding member 31a, the 1 st rotating cup 34, and the 2 nd rotating cup 35, for example. In this case, for example, while the rotary holding portion 31 is rotated, the DIW is supplied from the nozzle 41d while the nozzle 41d is reciprocated between the central portion and the outer peripheral portion of the rotary holding portion 31.

This makes it possible to remove crystals adhering to the rotating and holding portion 31 and the holding member 31a, the 1 st and 2 nd spin cups 34, 35 arranged on the outer peripheral portion of the rotating and holding portion 31.

Similarly, the return operation S4 is a process of pre-washing the rotating and holding portion 31, the holding member 31a, the 1 st rotor 34, and the 2 nd rotor 35 by the BHF in the subsequent step, for example. In this case, for example, while the rotation holding portion 31 is rotated, any one of the nozzles 41a to 41c (see fig. 2) is reciprocated between the central portion and the outer peripheral portion of the rotation holding portion 31, and BHF of the subsequent step is supplied from the nozzle.

This allows the DIW adhering to the rotating and holding portion 31 and the holding members 31a, the 1 st and 2 nd rotor cups 34, 35 arranged on the outer peripheral portion of the rotating and holding portion 31 to be replaced with the BHF in the subsequent step.

As shown in fig. 6B, the cleaning operation S3 is a process of cleaning the 1 st to 3 rd drain tanks 58a to 58c, for example. In this case, the processing unit 16 includes a cleaning liquid supply unit 100 that supplies DIW as a cleaning liquid to the 1 st drain tank 58 a.

The cleaning liquid supply unit 100 includes a cleaning liquid supply path 100a, a DIW supply source 100b, a valve 100c, and a flow rate adjuster 100 d. One end of the cleaning liquid supply path 100a is connected to the DIW supply source 100b, and the other end is connected to the drain port 51a of the 1 st cup 50 a. The valve 100c and the flow rate adjuster 100d are provided in the cleaning liquid supply path 100a and controlled by the control device 4.

In the cleaning operation S3 shown in fig. 6B, DIW is supplied to the 1 st drain tank 58a by opening the valve 100c for a predetermined time. Thus, the DIW is stored in the 1 st drain groove 58a, and the DIW stored in the 1 st drain groove 58a overflows the 1 st peripheral wall portion 54a on the upper surface 54a1 to the 2 nd drain groove 58b, and is stored in the 2 nd drain groove 58 b.

The DIW accumulated in the 2 nd drain groove 58b overflows to the 3 rd drain groove 58c over the upper surface 54b1 of the 2 nd peripheral wall portion 54b, and the DIW is also accumulated in the 3 rd drain groove 58 c.

Then, the DIW is discharged from the respective drain ports 51a to 51 c. This enables the crystals adhering to the 1 st to 3 rd drain grooves 58a to 58c to be removed.

Similarly, the recovery operation S4 is a process of performing a pre-wash of the 1 st to 3 rd drain tanks 58a to 58c by using, for example, BHF in the subsequent step. In this case, the processing unit 16 includes a processing liquid supply portion 101 that supplies BHF of the subsequent step to the 1 st drain tank 58 a.

The processing liquid supply unit 101 includes a processing liquid supply path 101a, a switching valve 101b, and a flow rate adjuster 101 c. One end of the processing liquid supply path 101a is connected to the reservoirs 70a to 70c via the switching valve 101b, and the other end is connected to the drain port 51a of the 1 st cup 50 a. The switching valve 101b and the flow rate adjuster 101c are provided in the treatment liquid supply path 101a and controlled by the control device 4.

In the return operation S4 shown in fig. 6B, the switching valve 101B is controlled to connect any one of the reservoirs 70a to 70c for storing the BHF in the subsequent step to the 1 st drain tank 58a, and the BHF in the subsequent step is supplied to the 1 st drain tank 58 a.

Thus, the BHF of the subsequent step is accumulated in the 1 st drain groove 58a, and the BHF of the subsequent step accumulated in the 1 st drain groove 58a overflows the 2 nd drain groove 58b over the upper surface 54a1 of the 1 st peripheral wall portion 54a, so that the BHF of the subsequent step is accumulated in the 2 nd drain groove 58 b.

Further, the BHF of the subsequent step accumulated in the 2 nd drain groove 58b overflows to the 3 rd drain groove 58c over the upper surface 54b1 of the 2 nd peripheral wall portion 54b, and the BHF of the subsequent step is also accumulated in the 3 rd drain groove 58 c.

Then, BHF in the subsequent step is discharged from the liquid discharge ports 51a to 51 c. This allows the DIW attached to the 1 st to 3 rd drainage grooves 58a to 58c to be replaced with BHF in the subsequent step.

As shown in fig. 6C, an exhaust cup 50d may be disposed between the 3 rd cup 50C (see fig. 2) and the antifogging cover 50e in the chamber 20. The exhaust cup 50d includes an outer peripheral tube portion 50d1 and an extension portion 50d2 extending radially inward from an upper end portion of the outer peripheral tube portion 50d1 to the outer peripheral tube portion 50d 1. Further, the exhaust cup 50d is stationary.

In this case, the cleaning operation S3 is, for example, a process of cleaning the lower surface of the extension 50e2 of the antifogging cover 50e and the upper surface of the extension 50d2 of the exhaust cup 50 d. In this case, the processing unit 16 includes, for example, a cleaning liquid supply portion 110 that supplies a cleaning liquid to the lower surface of the protruding portion 50e2 of the antifogging cover 50 e.

The cleaning liquid supply unit 110 includes a cleaning liquid supply path 110a, a DIW supply source 110b, a valve 110c, and a flow rate adjuster 110 d. One end of the cleaning liquid supply path 110a is connected to the DIW supply source 110b, and the other end is connected to the nozzle 41e provided on the upper surface of the extension portion 50d2 of the exhaust cup 50 d. The valve 110c and the flow rate adjuster 110d are provided in the cleaning liquid supply path 110a and controlled by the control device 4.

In the cleaning operation S3 shown in fig. 6C, the DIW is supplied from the nozzle 41e, and is accumulated in the space between the extension 50e2 of the antifogging cover 50e and the extension 50d2 of the exhaust cup 50 d. Thereafter, the DIW is discharged from a liquid discharge path not shown. This can remove crystals adhering to the lower surface of the extension portion 50e2 of the antifogging cover 50e and the upper surface of the extension portion 50d2 of the exhaust cup 50 d.

Similarly, the return operation S4 is a process of pre-washing the lower surface of the extension portion 50e2 of the antifogging cover 50e and the upper surface of the extension portion 50d2 of the exhaust cup 50d by, for example, BHF in the subsequent step. In this case, the processing unit 16 includes a processing liquid supply portion 111 that supplies BHF of the subsequent step to the nozzle 41 e.

The processing liquid supply unit 111 includes a processing liquid supply path 111a, a switching valve 111b, and a flow rate adjuster 111 c. One end of the processing liquid supply path 111a is connected to the reservoirs 70a to 70c via the switching valve 111b, and the other end is connected to the nozzle 41 e. The switching valve 111b and the flow rate adjuster 111c are provided in the treatment liquid supply path 111a and controlled by the control device 4.

In the return operation S4 shown in fig. 6C, the switching valve 111b is controlled to connect any one of the reservoirs 70a to 70C for storing the BHF in the subsequent step to the nozzle 41e, and the BHF in the subsequent step is supplied to the nozzle 41 e.

This causes the BHF in the subsequent step to be accumulated in the space between the extension portion 50e2 of the antifogging cover 50e and the extension portion 50d2 of the exhaust cup 50 d. Thereafter, BHF in the subsequent step is discharged from a liquid discharge path not shown. This allows the BHF in the subsequent step to replace the DIW adhering to the lower surface of the extension portion 50e2 of the antifogging cover 50e and the upper surface of the extension portion 50d2 of the exhaust cup 50 d.

As shown in fig. 6D, the cleaning operation S3 is a process of cleaning the lower surface of the rotation holding portion 31 of the substrate processing unit 30, for example. In this case, the processing unit 16 includes a cleaning liquid supply unit 120 that supplies a cleaning liquid to the lower surface of the rotary holding unit 31.

The cleaning liquid supply unit 120 includes a nozzle 41 f. The nozzle 41f is provided at, for example, an upper end of the inner wall 54 d. The cleaning liquid supply unit 120 includes a cleaning liquid supply path 120a, a DIW supply source 120b, a valve 120c, and a flow rate adjuster 120 d.

The cleaning liquid supply path 120a has one end connected to the DIW supply source 120b and the other end connected to the nozzle 41 f. The valve 120c and the flow rate adjuster 120d are provided in the cleaning liquid supply path 120a and controlled by the control device 4.

In the cleaning operation S3 shown in fig. 6D, DIW is supplied from the nozzle 41f to the lower surface of the rotating rotary holding portion 31. This can remove crystals adhering to the lower surface of the rotary holding portion 31.

Similarly, the return operation S4 is a process of pre-washing the lower surface of the rotation holding portion 31 of the substrate processing portion 30 by BHF in the subsequent step, for example. In this case, the processing unit 16 includes a processing liquid supply unit 121 that supplies BHF of the subsequent step to the nozzle 41 f.

The processing liquid supply unit 121 includes a processing liquid supply path 121a, a switching valve 121b, and a flow rate adjuster 121 c. One end of the processing liquid supply path 121a is connected to the reservoirs 70a to 70c via the switching valve 121b, and the other end is connected to the nozzle 41 f. The switching valve 121b and the flow rate adjuster 121c are provided in the treatment liquid supply path 121a and controlled by the control device 4.

In the return operation S4 shown in fig. 6D, the switching valve 121b is controlled to connect any one of the reservoirs 70a to 70c for storing the BHF in the subsequent step to the nozzle 41f, and the BHF in the subsequent step is supplied to the nozzle 41 f. Subsequently, BHF of the subsequent step is supplied from the nozzle 41f to the lower surface of the rotating holding portion 31, and DIW adhering to the lower surface of the rotating holding portion 31 can be replaced with the BHF of the subsequent step.

As shown in fig. 6E, the cleaning operation S3 is a process of cleaning the standby units 65a to 65c disposed in the chamber 20, for example. In this case, the processing unit 16 includes a cleaning liquid supply unit 130 that supplies a cleaning liquid to the standby units 65a to 65 c. Hereinafter, operations performed by the standby unit 65a shown in fig. 6E will be described for ease of understanding.

The cleaning liquid supply unit 130 includes a cleaning liquid supply path 130a, a DIW supply source 130b, a valve 130c, and a flow rate adjuster 130 d. One end of the cleaning liquid supply path 130a is connected to the DIW supply source 130b, and the other end is connected to the standby unit 65 a. The valve 130c and the flow rate adjuster 130d are provided in the cleaning liquid supply path 130a and controlled by the control device 4.

In the cleaning operation S3 shown in fig. 6E, after the DIW has been accumulated in the standby unit 65a for a predetermined time, the DIW is discharged from the standby unit 65a to the drainage path 59a (see fig. 3). This can remove crystals that have adhered to the standby portion 65 a.

Similarly, the recovery operation S4 is a process of performing a pre-wash of the standby part 65a provided in the chamber 20 by, for example, BHF in the subsequent step. In this case, the processing unit 16 includes a processing liquid supply unit 131 that supplies BHF of the subsequent step to the standby unit 65 a.

The processing liquid supply unit 131 includes a processing liquid supply path 131a, a valve 131b, and a flow rate adjuster 131 c. One end of the treatment liquid supply path 131a is connected to the corresponding reservoir 70a via a valve 131b, and the other end is connected to the standby unit 65 a. The valve 131b and the flow rate adjuster 131c are provided in the processing liquid supply path 131a and controlled by the control device 4.

In a return operation S4 shown in fig. 6E, the valve 131b is controlled to connect the reservoir 70a for storing the BHF in the subsequent step and the standby portion 65a, and the BHF in the subsequent step is supplied to the standby portion 65 a.

Next, after the BHF of the subsequent step is accumulated in the standby portion 65a for a predetermined time, the BHF of the subsequent step is discharged from the standby portion 65a to the drainage path 59 a. This enables the DIW attached to the standby portion 65a to be replaced with BHF in the subsequent step.

As shown in fig. 6F, a back nozzle 47 for discharging a processing liquid or the like to the back surface of the wafer W may be disposed in the chamber 20. The back nozzle 47 is an example of a back supply unit. The back nozzle 47 is provided so as to face the back surface of the wafer W held by the holding member 31a, and discharges the processing liquid or the like in an upward direction.

The back surface nozzle 47 has a treatment liquid discharge port 47a for discharging the 1 st to 3 rd BHF as the treatment liquid and a cleaning liquid discharge port 47b for discharging DIW as the cleaning liquid. The back surface nozzle 47 is provided in the processing unit 16, and can perform liquid processing not only on the front surface of the wafer W but also on the back surface of the wafer W by using BHF.

The cleaning operation S3 shown in fig. 6F (a) is, for example, to supply the DIW from the nozzle 41d while reciprocating the nozzle 41d between the center portion and the outer peripheral portion of the back surface nozzle 47 in a state where the wafer W is not held by the holding member 31 a. This enables crystals adhering to the rear surface nozzle 47 to be removed.

Similarly, the recovery operation S4 shown in fig. 6F (b) is a process of pre-washing the back nozzle 47 with BHF in the subsequent step, for example. In this case, for example, in a state where the wafer W is not held by the holding member 31a, any one of the nozzles 41a to 41c (the nozzle 41a in the figure) is supplied from the nozzle to the BHF in the subsequent step while reciprocating between the center portion and the outer peripheral portion of the back surface nozzle 47. This enables the DIW attached to the back nozzle 47 to be replaced with BHF in the subsequent step.

The cleaning operation S3 and the recovery operation S4 of the back nozzle 47 are not limited to the example shown in fig. 6F. For example, as shown in fig. 6G (a), DIW as the cleaning liquid may be discharged from the cleaning liquid discharge port 47b and the DIW may be overflowed to the back surface nozzle 47, thereby performing the cleaning operation S3 of the back surface nozzle 47. This enables crystals adhering to the rear surface nozzle 47 to be removed.

Next, as shown in fig. 6G (b), the BHF of the subsequent step may be discharged from the treatment liquid discharge port 47a, and the BHF of the subsequent step may be overflowed to the back surface nozzle 47, thereby performing the recovery operation S4 of the back surface nozzle 47. This enables the DIW attached to the back nozzle 47 to be replaced with BHF in the subsequent step.

In addition, cleaning process S2 may be performed by combining cleaning operation S3 and recovery operation S4 shown in fig. 6F and cleaning operation S3 and recovery operation S4 shown in fig. 6G. For example, after the rinsing operation S3 in which DIW is supplied from the nozzle 41d, BHF of the subsequent step may be discharged from the treatment liquid discharge port 47a of the rear surface nozzle 47 to perform the recovery operation S4.

Similarly, after the cleaning operation S3 is performed by discharging DIW from the cleaning liquid discharge port 47b of the back nozzle 47, the BHF of the subsequent step may be supplied from any one of the nozzles 41a to 41c, and the recovery operation S4 may be performed.

In the cleaning operation S3 and the recovery operation S4 of each part described above, the controller 18 preferably controls the switching valves 63a to 63c (see fig. 3) to discharge the liquid discharged to the liquid discharge paths 59a to 59c from the drain DR to the outside.

Fig. 7 is a graph showing a relationship between the time of the recovery operation S4 and the amount of change in the etching rate in the subsequent treatment process S1b according to the embodiment. Fig. 7 shows the recovery operation S4 performed for the standby units 65a to 65c (see fig. 6E) and the recovery operation S4 performed for the 1 st to 3 rd drain tanks 58a to 58c (see fig. 6B), respectively.

As shown in fig. 7, it can be seen that: if the time for the recovery operation S4 is relatively short, the etching rate is greatly reduced in the subsequent processing step S1. This is because, when the time for the recovery operation S4 is relatively short, the DIW used in the cleaning operation S3 remains in the substrate processing portion 30 and the drain portion 50 relatively much, and therefore the BHF recovered in the subsequent processing step S1b is mixed with the DIW, and the concentration of the recycled BHF is reduced.

On the other hand, as shown in fig. 7, by extending the time of the recovery operation S4, the etching rate in the subsequent treatment process S1 can be maintained within an appropriate range.

That is, the drain liquid flowing through the drain paths 59a to 59c in the cleaning operation S3 and the recovery operation S4 is discharged to the outside from the drain portion DR, and thus the collection of the DIW as the cleaning liquid and the BHF containing the DIW into the storage portions 70a to 70c can be suppressed.

In the embodiment, the recovery operation S4 is performed for a time corresponding to the BHF in the subsequent step, whereby the etching rate in the subsequent processing step S1b can be maintained within an appropriate range even when the reused BHF is used.

As described above, according to the embodiment, since the concentration of the collected BHF can be suppressed from decreasing, the performance of the liquid treatment can be suppressed from deteriorating.

In addition, the above-mentioned "time recovery operation S4 according to the BHF of the subsequent step" is preferably included in the cleaning process S2 according to the type of the BHF included in the treatment process S1b of the subsequent step. That is, in the embodiment, the cleaning process S2 is preferably selected based on the treatment process S1b subsequent to the cleaning process S2.

For example, when the 1 st BHF is used in the treatment process S1b in the subsequent step, the controller 18 preferably reads out the cleaning process S2 used in the recovery operation S4 of the 1 st BHF from the storage unit 19. The read cleaning process S2 includes the execution time of the recovery action S4 corresponding to the 1 st BHF.

In this way, by selecting the cleaning process S2 based on the treatment process S1b in the subsequent step, the liquid treatment in the subsequent step can be started in a state where the substrate treatment portion 30 and the like are replaced with BHF used in the treatment process S1b in the subsequent step. Therefore, according to the embodiment, when the BHF used in the treatment step S1b is recovered and reused, the change in the concentration of the BHF can be suppressed, and therefore, the liquid treatment in the subsequent step can be stably performed.

In the embodiment, in the return operation S4, when BHF of the subsequent step is ejected from any one of the nozzles 41a to 41c for the pre-washing, the liquid treatment of the wafer W may be performed using the ejected BHF of the subsequent step.

Accordingly, the liquid processing of the wafer W can be executed in the process of the return operation S4, and therefore, the processing unit 16 can be returned to the liquid processing at an early stage.

< various modifications >

Next, various modifications of the embodiment will be described with reference to fig. 8 and 9. Fig. 8 is a diagram for explaining a flow of processing in the substrate processing system 1 according to modification 1 of the embodiment.

As shown in fig. 8, the cleaning process S2 of modification 1 differs from the embodiment in the following points: a gas purge operation S5 is performed between the cleaning operation S3 and the recovery operation S4. In the modification 1, the process unit 16 includes a gas supply unit (not shown) for purging gas to the substrate processing unit 30 and the drain unit 50.

In modification 1, after the controller 18 (see fig. 1) performs the cleaning operation S3, the following gas purging operation S5 is performed: the gas is supplied from the gas supply unit to purge the DIW adhering to the substrate processing unit 30 and the liquid discharge unit 50.

This can reduce DIW adhering to the substrate processing unit 30 and the liquid discharge unit 50 before the return operation S4. Therefore, according to the embodiment, since the time required for the return operation S4 can be shortened, the processing unit 16 can be returned to the liquid processing at an early stage.

In the gas purge operation S5, the controller 18 preferably supplies the gas to the portion where the DIW is accumulated. In particular, it is preferable that the gas purging operation S5 be performed in the vicinity of the movable portion (for example, the 1 st liquid receiving portion 55a, the 2 nd liquid receiving portion 55b, the 1 st supporting member 56a, the 2 nd supporting member 57a, and the like) in the process unit 16 because the DIW enters a narrow gap and is hardly replaced even when the prewashing is performed.

This can further reduce DIW adhering to the substrate processing unit 30 and the liquid discharge unit 50 before the return operation S4.

Fig. 9 is a diagram for explaining a flow of processing in the substrate processing system 1 according to modification 2 of the embodiment. In the cleaning process S2 of modification 2, the concentration of hydrofluoric acid in the liquid discharged to the liquid discharge paths 59a to 59c (see fig. 3) is detected by the concentration sensors 62a to 62c (see fig. 3) at the time of the return operation S4.

The control unit 18 performs a determination operation S6 of determining whether or not the concentration of hydrofluoric acid in the liquid discharged to the liquid discharge paths 59a to 59c is appropriate.

When the DIW in the substrate processing section 30 and the drain section 50 is replaced with the BHF in the subsequent step by the recovery operation S4 and the concentration of hydrofluoric acid in the drain liquid is appropriate, the controller 18 ends the recovery operation S4 and starts the next processing step S1 b.

At this time, the controller 18 controls the switching valves 63a to 63c (see fig. 3) to switch the discharge path of the waste liquid flowing through the waste liquid paths 59a to 59c to the recovery paths 64a to 64c (see fig. 3). This enables the processing step S1b to be executed while collecting BHF in the subsequent step.

On the other hand, if the DIW in the substrate processing section 30 and the drain section 50 is not sufficiently replaced and the concentration of the hydrofluoric acid in the drain liquid is not appropriate, the control section 18 continues the return operation S4.

At this time, the controller 18 controls the switching valves 63a to 63c to maintain the discharge path of the discharged liquid flowing through the discharge paths 59a to 59c by the drain DR. This can further suppress the collection of BHF mixed with DIW.

That is, in modification 2 shown in fig. 9, recovery operation S4 is executed while the concentration of hydrofluoric acid in the drain liquid flowing through the drain liquid paths 59a to 59c is detected by the concentration sensors 62a to 62c, whereby the BHF in which DIW is mixed can be further suppressed from being recovered.

This modification 2 is preferably applied to, for example, BHFs having a high hydrofluoric acid concentration among BHFs having various hydrofluoric acid concentrations, which are BHFs to be used in subsequent steps. In this BHF having a high hydrofluoric acid concentration, the etching rate greatly changes even when a slight amount of DIW is mixed. That is, the BHF having a high hydrofluoric acid concentration has higher sensitivity to DIW than the BHF having a low hydrofluoric acid concentration.

In this way, by applying the above-described determination operation S6 to BHF having a high sensitivity to DIW, the recovered liquid of the BHF can be prevented from being mixed with DIW, and therefore, the liquid treatment using the recovered liquid can be stably performed.

Further, when the BHF having a high hydrofluoric acid concentration is the BHF of the subsequent step, it is preferable to apply the gas purging operation S5 of modification 1 in addition to the determination operation S6 of modification 2. Thus, the amount of DIW that may be mixed into the BHF itself is reduced by the gas purging operation S5, and therefore, the liquid treatment using the recovered liquid can be performed more stably.

The substrate processing apparatus (substrate processing system 1) according to the embodiment includes a substrate processing unit 30, a liquid discharge unit 50, and a control unit 18. The substrate processing unit 30 performs liquid processing by supplying a processing liquid from a processing liquid supply unit to a substrate (wafer W) mounted thereon. The liquid discharge unit 50 has recovery paths 64a to 64c connected to reservoirs 70a to 70c for storing the treatment liquid, and discharges the treatment liquid used for the liquid treatment. The controller 18 performs a liquid treatment process S1 and a cleaning process S2 for cleaning the substrate treatment unit 30 and the drain unit 50. In addition, as the cleaning process S2, the controller 18 performs a cleaning operation S3 of supplying the cleaning liquid from the cleaning liquid supply unit to clean the substrate processing unit 30 and the drain unit 50, and then performs a recovery operation S4 of supplying the processing liquid from the processing liquid supply unit to replace the cleaning liquid adhering to the substrate processing unit 30 and the drain unit 50 with the processing liquid. This can suppress deterioration of the performance of the liquid treatment.

In the substrate processing apparatus (substrate processing system 1) according to the embodiment, the processing process S1 includes the order of processing the substrate (wafer W) and the type of the processing liquid. Thus, the liquid processing optimized for the different types of processing liquids can be performed by the processing unit 16.

In the substrate processing apparatus (substrate processing system 1) according to the embodiment, the cleaning process S2 is selected based on the type of the processing liquid included in the processing process S1. This enables stable liquid treatment in the subsequent step.

In the substrate processing apparatus (substrate processing system 1) according to the embodiment, the cleaning process S2 is selected based on the processing process S1b which is a subsequent step of the cleaning process S2. This enables stable liquid treatment in the subsequent step.

In the substrate processing apparatus (substrate processing system 1) according to the embodiment, the drain portion 50 includes a drain portion DR that discharges the processing liquid to the outside. The controller 18 discharges the drain liquid flowing through the drain paths 59a to 59c from the drain DR to the outside while the cleaning process S2 is being performed. This can suppress the collection of BHF mixed with DIW.

In the substrate processing apparatus (substrate processing system 1) according to the embodiment, the liquid discharge unit 50 includes concentration sensors 62a to 62c for detecting the concentration of the processing liquid. Then, the control unit 18 ends the return operation S4 based on the concentrations of the processing liquids detected by the concentration sensors 62a to 62 c. This can further suppress the collection of BHF mixed with DIW.

The substrate processing apparatus (substrate processing system 1) according to the embodiment includes a gas supply unit configured to supply a gas to the substrate processing unit 30 and the liquid discharge unit. After the cleaning operation S3, the controller 18 performs a gas purging operation S5 in which the cleaning liquid adhering to the substrate processing unit 30 and the liquid discharge unit 50 is purged by supplying the gas. This enables the processing unit 16 to be returned to the liquid processing earlier.

In the substrate processing apparatus (substrate processing system 1) according to the embodiment, the controller 18 supplies the gas to the portion where the cleaning liquid is retained as the gas purge operation S5. This can further reduce the amount of cleaning liquid adhering to the substrate processing unit 30 and the liquid discharge unit 50 before the return operation S4.

The substrate processing apparatus (substrate processing system 1) according to the embodiment includes standby units 65a to 65c for waiting for the processing liquid supply unit, and the drain paths of the standby units 65a to 65c are connected to the drain paths 59a to 59c of the drain unit 50. The control unit 18 performs a cleaning process S2 similar to the substrate processing unit 30 for the processing units 65a to 65 c. This can suppress the collection of BHF mixed with DIW adhering to the standby portions 65a to 65 c.

The substrate processing apparatus (substrate processing system 1) according to the embodiment includes a back surface supply unit (back surface nozzle 47) that discharges a processing liquid to the back surface side of the substrate (wafer W). Then, the control unit 18 performs a cleaning process S2 on the back surface supply unit (back surface nozzle 47). This can suppress the collection of BHF mixed with DIW adhering to the back nozzle 47.

< sequence of substrate treatment >

Next, the procedure of substrate processing according to the embodiment will be described with reference to fig. 10. Fig. 10 is a flowchart showing a procedure of substrate processing performed by the substrate processing system 1 according to the embodiment.

First, the control unit 18 performs a cleaning process selection process of selecting the cleaning process S2 based on the predetermined process S1b to be executed next (step S101). For example, the controller 18 selects BHF of a subsequent step included in the predetermined treatment process S1b to be executed next and a cleaning process S2 including BHF of the same kind.

When the selected cleaning process S2 is process a (step S102, process a), the control unit 18 performs a cleaning process based on the selected process a (step S103). The process a is, for example, a cleaning process S2 in the case where the BHF of the subsequent process is the 1 st BHF.

In addition, in step S103, DIW is supplied as a cleaning liquid from a cleaning liquid supply unit (for example, the nozzle 41d) and the substrate processing unit 30 and the drain unit 50 are cleaned by the DIW. In step S103, crystals caused by BHF adhering to the substrate processing portion 30 and the liquid discharge portion 50 can be removed.

Next, the control unit 18 performs the following recovery processing based on the selected process a: BHF of the subsequent step is supplied from the treatment liquid supply portion, and DIW adhering to the substrate treatment portion 30 and the drain portion 50 is replaced with BHF (step S104). This can prevent the DIW remaining in the substrate processing section 30 and the drain section 50 from being collected into the accumulating sections 70a to 70 c.

Then, the process of step S104 is performed at a time determined in advance in the process a, and when the process is completed, the control unit 18 terminates the series of processes.

On the other hand, when the cleaning process S2 selected in step S101 is the process B (step S102, process B), the control unit 18 performs a cleaning process based on the selected process B (step S105). The process B is, for example, a cleaning process S2 in the case where the BHF of the subsequent process is 2 nd BHF.

In addition, in step S105, DIW is supplied as a cleaning liquid from a cleaning liquid supply unit (for example, the nozzle 41d) and the substrate processing unit 30 and the drain unit 50 are cleaned by the DIW. In step S105, crystals caused by BHF adhering to the substrate processing portion 30 and the liquid discharge portion 50 can be removed.

Next, the controller 18 performs the following gas purge processing based on the selected process B: a gas is supplied from a gas supply unit provided in the process unit 16, and DIW adhering to the substrate processing unit 30 and the drain unit 50 is purged (step S106). This can reduce DIW adhering to the substrate processing section 30 and the drain section 50 before the recovery process to be performed next.

Next, the control unit 18 performs the following recovery processing based on the selected process B: BHF of the subsequent step is supplied from the treatment liquid supply portion, and DIW adhering to the substrate treatment portion 30 and the drain portion 50 is replaced with BHF (step S107). This can prevent the DIW remaining in the substrate processing section 30 and the drain section 50 from being collected into the accumulating sections 70a to 70 c.

Then, the process of step S107 is performed at a time determined in advance in the process B, and when the process is completed, the control unit 18 terminates the series of processes.

In addition, when the cleaning process S2 selected in step S101 is the process C (step S102, process C), the control unit 18 performs the cleaning process based on the selected process C (step S108). The process C is, for example, a cleaning process S2 in the case where the BHF of the subsequent process is the 3 rd BHF.

In addition, in step S108, DIW is supplied as a cleaning liquid from a cleaning liquid supply unit (for example, the nozzle 41d) and the substrate processing unit 30 and the drain unit 50 are cleaned by the DIW. In step S108, crystals caused by BHF adhering to the substrate processing portion 30 and the liquid discharge portion 50 can be removed.

Next, the controller 18 performs the following gas purge processing based on the selected process C: a gas is supplied from a gas supply unit provided in the process unit 16, and DIW adhering to the substrate processing unit 30 and the drain unit 50 is purged (step S109). This can reduce DIW adhering to the substrate processing section 30 and the drain section 50 before the recovery process to be performed next.

Next, the control unit 18 performs the following recovery processing based on the selected process C (step S110): BHF in the subsequent step is supplied from the treatment liquid supply portion, and DIW adhering to the substrate treatment portion 30 and the drain portion 50 is replaced with BHF. This can prevent the DIW remaining in the substrate processing section 30 and the drain section 50 from being collected into the accumulating sections 70a to 70 c.

Next, the control unit 18 determines whether or not the concentration of hydrofluoric acid in the liquid discharged to the liquid discharge paths 59a to 59c is appropriate (step S111).

When the concentration of the hydrofluoric acid in the discharged liquid is appropriate (yes in step S111), the control unit 18 ends the series of processing. On the other hand, when the hydrofluoric acid concentration in the discharged liquid is not appropriate (no in step S111), the control unit 18 continues the process of step S110.

As described above, in the substrate processing method according to the embodiment, the cleaning process S2 (process a to process C) is selected in accordance with the processing process S1b, and an optimum cleaning process according to the type of BHF used in the processing process S1b can be performed.

The substrate processing method of an embodiment includes a liquid processing step and a cleaning step. The liquid treatment process performs the following treatment process S1: the processing liquid is supplied from the processing liquid supply unit (nozzles 41a to 41c) to the substrate (wafer W) placed on the substrate processing unit 30, and the used processing liquid is collected from the drain unit 50 into the reservoirs 70a to 70 c. The cleaning step is performed as a cleaning step S2 of cleaning the processing liquid adhering to the substrate processing unit 30 and the drain unit 50 during the liquid processing step. The cleaning step includes a cleaning operation S3 of supplying the cleaning liquid to clean the substrate processing section 30 and the drain section, and a recovery operation S4 of supplying the processing liquid to replace the cleaning liquid adhering to the substrate processing section 30 and the drain section 50 with the processing liquid. This can suppress deterioration of the performance of the liquid treatment.

While the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit thereof. For example, in the above-described embodiment, the case where the cleaning liquid DIW and the treatment liquid BHF are used has been described, but the cleaning liquid and the treatment liquid according to the embodiment are not limited to this example.

The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. In fact, the above-described embodiments can be embodied in various forms. Further, the above-described embodiments may be omitted, replaced, or modified in various forms without departing from the scope of the appended claims and the gist thereof.