JP2016149470A - Substrate processing apparatus, substrate processing method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve drying performance even in the case where drying treatments on both surfaces of a substrate are performed in parallel.SOLUTION: In a substrate processing device 1 and a substrate processing method of performing liquid processing on a wafer W by supplying a liquid to a substrate (wafer W), in the case where received setting information includes processing of performing drying on a top face and an undersurface of the wafer W in parallel, a control part 16 changes setting information of a supply amount of the drying gas to the top face of the wafer W by the drying gas supply mechanism 74 depending on a supply amount of a drying gas to the undersurface of the wafer W by a drying gas supply mechanism 72.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a technique for performing liquid processing by supplying a processing liquid to a substrate.

  In manufacturing a semiconductor device, a substrate such as a semiconductor wafer is held horizontally and rotated around a vertical axis, and a cleaning liquid (for example, a cleaning chemical or a rinsing liquid) is supplied to the lower surface of the substrate. A cleaning process may be applied. After the bottom surface cleaning process is completed, a drying process is performed. In the drying process, the substrate is spun off by rotating the substrate at a high speed. At this time, an inert gas such as nitrogen gas is supplied to the lower surface side of the substrate in order to promote drying and prevent the generation of a water mark. For example, Patent Document 1 discloses a substrate liquid processing apparatus for executing the above-described series of processes.

Japanese Patent No. 5005571

  When the bottom surface of the substrate is cleaned and dried, the top surface of the substrate may be cleaned and dried in parallel. Here, in the drying process for the lower surface, in order to improve the drying performance, the supply amount of the inert gas to the lower surface may be increased. However, if the top surface drying process is also performed in parallel, if the supply amount to the bottom surface is increased, the temperature of the substrate top surface also decreases due to the heat of vaporization due to drying, and the drying time of the substrate top surface may be extended. is there.

  The present invention is for solving the above-described problems, and an object of the present invention is to improve the drying performance when the drying processes on both sides of the substrate are performed in parallel.

  In order to solve the above-described problems, a substrate processing apparatus according to the present invention is a substrate processing apparatus that performs liquid processing on a substrate by supplying a liquid to the substrate, and the upper surface of the liquid processed substrate A first gas supply mechanism for supplying a drying gas; a second gas supply mechanism for supplying a drying gas to the lower surface of the liquid-treated substrate; and a first gas supply mechanism and a first gas supply mechanism based on the received setting information. A control unit that controls liquid processing using a two-gas supply mechanism, and when the setting information includes a process of drying the upper surface and the lower surface of the liquid processed substrate in parallel, the control unit includes: The setting information of the supply amount of the drying gas to the upper surface of the substrate by the first gas supply mechanism is changed according to the supply amount of the drying gas to the lower surface of the substrate by the second gas supply mechanism.

  According to the present invention, when the drying processes on both sides of the substrate are performed in parallel, the drying performance can be improved by shortening the drying time using an appropriate amount of drying gas.

1 is a diagram illustrating a schematic configuration of a substrate processing system according to a first embodiment. It is a schematic longitudinal cross-sectional view of the process unit contained in the substrate liquid processing apparatus of FIG. FIG. 3 is a diagram illustrating a configuration of a fluid supply mechanism for a lower surface of a wafer W. It is a figure which shows the structure of a fluid supply system. It is a figure explaining the operation | movement at the time of performing the cleaning process and the drying process in a substrate processing apparatus. It is a flowchart which shows control of the gas supply for a drying process. It is a figure which shows the experimental result of a drying process. It is a figure which shows the structure of the board | substrate holding part in 2nd Embodiment. It is a figure explaining board | substrate holding | maintenance operation | movement. It is a schematic diagram which shows the operation state of the washing process with a brush.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

(First embodiment)
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 wafers W (substrates) 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 substrate holding mechanism that holds the wafer W. Further, the substrate transfer device 13 can move in the horizontal direction and the vertical direction and turn around the vertical axis, and transfers the wafer W between the carrier C and the delivery unit 14 using the substrate 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 substrate 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 the substrate 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.

  Next, a schematic configuration of the processing unit 16 will be described with reference to FIGS.

  As shown in FIG. 2, the processing unit 16 is supplied to the chamber 20, a substrate holding and rotating mechanism 30 that holds and rotates the wafer W, a liquid discharge unit 40 that constitutes a processing liquid supply nozzle, and the wafer W. And a recovery cup 50 for recovering the subsequent processing liquid.

  The chamber 20 accommodates the substrate holding and rotating mechanism 30, the liquid discharge unit 40, and the recovery cup 50. An FFU (Fan Filter Unit) 21 is provided on the ceiling of the chamber 20. The FFU 21 forms a down flow in the chamber 20.

  The substrate holding and rotating mechanism 30 is configured as a mechanical chuck that holds the wafer W by a mechanical clamping mechanism. The substrate holding and rotating mechanism 30 includes a substrate holding unit 31, a rotation shaft 32, and a rotation motor (rotation drive unit) 33.

The substrate holding part 31 has a disk-shaped base plate (plate-like body) 31a and a plurality of holding members 31b provided on the peripheral edge of the base plate 31a. The holding member 31 b is formed on the upper part of the base plate 31 a and holds the periphery of the wafer W. Thus, a lower space 83 is formed between the lower surface of the wafer W and the upper surface of the base plate 31a. In the present embodiment, some of the plurality of holding members 31b are movable support members that move back and forth with respect to the wafer W to switch between gripping and releasing the wafer W, and the remaining holding members 31b are non-moving holding members. It is. The rotating shaft 32 is hollow and extends vertically downward from the center of the base plate 31a. The rotation motor 33 drives the rotation shaft 32 to rotate, whereby the wafer W held in a horizontal posture by the substrate holding unit 31 rotates around the vertical axis.

  The liquid ejection part 40 is formed as an elongated shaft-like member extending in the vertical direction. The liquid discharge part 40 has a hollow cylindrical shaft part 41 extending in the vertical direction and a head part 42. The shaft portion 41 is inserted into a cylindrical cavity 32 a inside the rotation shaft 32 of the substrate holding and rotating mechanism 30. The shaft portion 41 and the rotation shaft 32 are concentric. A space as a gas passage 80 having an annular cross section is formed between the outer peripheral surface of the shaft portion 41 and the inner peripheral surface of the rotating shaft 32.

  Inside the liquid ejection part 40 is a cylindrical cavity extending in the vertical direction. A processing liquid supply pipe 43 (see FIG. 3) is provided inside the cavity. The upper end of the processing liquid supply pipe 43 is opened at the top part 42 a of the head 42 of the liquid discharging part 40, and the processing liquid is discharged toward the center part of the lower surface of the wafer W held by the substrate holding and rotating mechanism 30. (See the black arrow in FIG. 3), the liquid discharge port 43a is obtained. Here, the top portion 42a is a thin ring-shaped planar region surrounding the liquid discharge port 43a, and is a portion connecting the liquid discharge port 43a and a curved portion 42d described later.

  A predetermined processing liquid for processing the lower surface of the wafer W is supplied from the processing liquid supply mechanism 71 to the processing liquid supply pipe 43. A detailed description of the configuration of the processing liquid supply mechanism 71 will be described later. In this embodiment, the processing liquid supply mechanism 71 supplies pure water (DIW), but a plurality of processing liquids, for example, a cleaning chemical (for example, DHF) and a rinsing liquid can be switched and supplied. It may be configured as follows. Nitrogen (N2) is supplied from the drying gas supply mechanism 72 (second gas supply mechanism) to the gas passage 80 as a drying gas for drying the lower surface of the wafer W. A detailed description of the configuration of the drying gas supply mechanism 72 will be given later.

  The periphery of the upper portion of the liquid ejection unit 40 (the head 42 and the vicinity thereof) is surrounded by a cavity 32a of the rotating shaft 32. There is an annular gap between the upper part of the liquid ejection part 40 and the surrounding member, and this gap forms a gas ejection path 81 through which a drying gas passes.

  A gas discharge port 31d is defined on the upper surface of the central portion of the base plate 31a by the outer peripheral edge 42b of the head portion 42 of the liquid discharge portion 40 (the end portion of the cover portion 42c) and the surface 31c of the substrate holding portion. Here, the outer peripheral edge 42b is a portion of the head 42 that is located on the outermost radial direction. The gas discharge port 31d is an annular discharge port that discharges the gas flowing through the annular gas discharge path 81 to a lower space 83 of the wafer W (a space between the wafer W and the base plate 31a).

  The collection cup 50 is disposed so as to surround the substrate holding portion 31 of the substrate holding and rotating mechanism 30 and collects the processing liquid scattered from the rotating wafer W. The recovery cup 50 has a stationary lower cup body 51 and an upper cup body 52 that can be raised and lowered between a raised position (position shown in FIG. 2) and a lowered position. The upper cup body 52 is moved up and down by the lifting mechanism 53. When the upper cup body 52 is in the lowered position, the upper end of the upper cup body 52 is located at a position lower than the wafer W held by the substrate holding and rotating mechanism 30. For this reason, when the upper cup body 52 is in the lowered position, the wafer W is moved between the substrate holding mechanism (arm) of the substrate transport apparatus 17 shown in FIG. Can be delivered.

  A discharge port 54 is formed at the bottom of the lower cup body 51. The collected processing liquid and the atmosphere in the recovery cup 50 are discharged from the recovery cup 50 through the discharge port 54. A discharge pipe 55 is connected to the discharge port 54, and the discharge pipe 55 is connected to a factory exhaust system (not shown) in a reduced pressure atmosphere.

  The downflow of clean air from the FFU 21 is drawn into the recovery cup 50 through the upper opening of the recovery cup 50 (upper cup body 52) and exhausted from the discharge port 54. For this reason, an air flow indicated by an arrow F is generated in the recovery cup 50.

  The processing unit 16 further includes at least one processing liquid supply nozzle 62 that supplies a processing liquid (cleaning chemical and rinsing liquid) to the upper surface of the wafer W held by the substrate holding and rotating mechanism 30. The processing unit 16 further includes a brush 63 for scrub cleaning the upper surface of the wafer W.

  A predetermined processing liquid for processing the upper surface of the wafer W is supplied from the processing liquid supply mechanism 73 to the processing liquid supply nozzle 62. The gas supply port 61 is provided above the rotation center of the wafer W, and N2 as a drying gas for performing a drying process is supplied from a drying gas supply mechanism 74 (first gas supply mechanism). A detailed description of the configuration of the processing liquid supply mechanism 73 and the drying gas supply mechanism 74 will be given later.

  FIG. 4 shows the configuration of a fluid supply system that supplies and discharges the processing liquid and drying gas of the substrate liquid processing apparatus in this embodiment.

  In the drying gas supply mechanism 72 of FIG. 4, a drying gas supply source 401 is a supply source of a drying gas (N2) used for the drying process. The drying gas supply line 402 is a supply path for supplying the drying gas from the drying gas supply source 401 to the chamber 20. The opening / closing valve 403 is interposed in the drying gas supply line 402 and controls the start and stop of the supply of the drying gas to the chamber 20. The flow rate controller 404 is provided in the drying gas supply line 402 and adjusts the flow rate of the drying gas supplied from the drying gas supply line 402 to the chamber 20.

  In the processing liquid supply mechanism 71 of FIG. 4, a processing liquid supply source 405 is a processing liquid supply source used for liquid processing, and is a supply source of pure water (DIW) that is the processing liquid of this embodiment. The processing liquid supply line 406 is a supply path for supplying the processing liquid from the processing liquid supply source 405 to the chamber 20. The opening / closing valve 407 is provided in the processing liquid supply line 406 and controls the start and stop of the supply of the processing liquid to the chamber 20. The flow rate adjuster 408 is provided in the processing liquid supply line 406 and adjusts the flow rate of the processing liquid supplied from the processing liquid supply source 405 to the processing liquid supply line 406.

  4 has the same configuration as the drying gas supply mechanism 72. In the drying gas supply mechanism 74, the drying gas supply source 409 includes the drying gas supply source 401 and the drying gas supply mechanism 401. The gas supply line 410 has the same function as the drying gas supply line 402, the open / close valve 411 has the open / close valve 403, and the flow rate regulator 412 has the same function.

  4, the processing liquid supply source 413 has the same function as the processing liquid supply source 405, and the processing liquid supply line 414 has the same function as the processing liquid supply line 406. The processing liquid supply source 415 is a supply source of DHF that is the processing liquid of the present embodiment. The processing liquid supply line 416 is a supply path for supplying the processing liquid from the processing liquid supply source 415 to the chamber 20. The switching valve 417 is connected to the processing liquid supply line 414 and the processing liquid supply line 416, and switches either DIW or DHF to be supplied to the chamber 20 and controls the start and stop of the supply. To do. The flow rate adjuster 418 is provided in the processing liquid supply line 414 and adjusts the flow rate of the processing liquid supplied from the processing liquid supply source 413 to the processing liquid supply line 414. The flow rate regulator 419 is interposed in the processing liquid supply line 416 and adjusts the flow rate of the processing liquid supplied from the processing liquid supply source 415 to the processing liquid supply line 416.

  Next, the operation | movement at the time of performing the washing | cleaning process and the drying process in the substrate processing apparatus of this embodiment is demonstrated using FIG.

  In this embodiment, processing is performed in parallel with the upper and lower surfaces of the wafer W having a radius of 150 mm. (1) Upper surface cleaning processing / lower surface cleaning processing, (2) Upper surface cleaning (rinsing) processing / lower surface cleaning The process is executed in the order of (3) upper surface drying process / lower surface drying process. Here, the description (A process / B process) indicates that the A process and the B process are performed in parallel, that is, at least a partial overlap period in the entire time for executing each process on the upper surface and the lower surface. (Time for processing the upper surface and the lower surface at the same time) is provided, and the mutual processing is executed. Note that the control unit 18 increases or decreases the amount of fluid supplied in order to increase or decrease the amount of fluid supplied, the processing liquid supply mechanism 71, the drying gas supply mechanism 72 (second gas supply mechanism), the processing liquid supply mechanism 73, and the drying gas supply mechanism 74. (The first gas supply mechanism) controls the on-off valve and the flow rate regulator.

  FIG. 5A is a schematic diagram showing an operation state of (1) upper surface cleaning process / lower surface cleaning process. In this operation, the wafer W is rotating at a predetermined rotation speed (for example, 1000 rpm). Here, with respect to the upper surface, DIW is supplied from the processing liquid supply nozzle 62 to the center of the wafer W, a liquid film is formed on the substrate surface, a brush 63 is brought into contact with the upper surface of the substrate, and scanning in the horizontal direction is performed. Physically clean the substrate surface. Here, chemical treatment with DHF may be performed without being limited to physical cleaning using the brush 63. On the other hand, the lower surface is cleaned by supplying DIW to the center of the wafer W from the processing liquid supply pipe 43.

  FIG. 5B is a schematic diagram showing an operation state of (2) top surface cleaning (rinsing) processing / bottom surface cleaning processing executed after the cleaning processing (1). In this operation, the wafer W is rotating at a predetermined rotation speed (for example, 1000 rpm). Here, with respect to the upper surface, cleaning by the brush 63 is stopped, and DIW is supplied from the processing liquid supply nozzle 62 to the center of the wafer W to perform cleaning (rinsing). On the other hand, the lower surface is cleaned by supplying DIW to the center of the wafer W from the processing liquid supply pipe 43.

FIG. 5C is a schematic diagram showing (3) upper surface drying process / lower surface drying process performed after the cleaning process (2). Here, regarding the upper surface, the drying gas (N2) is supplied from the gas supply port 61 to perform the drying process on the upper surface, and the drying gas (N2) is also supplied from the gas passage 80 to the lower surface. Then, the drying process is performed.
Next, FIG. 6 is a flowchart of a setting change operation of a recipe (setting information) for controlling the gas supply of the gas supply port 61 and the gas passage 80 when performing the upper surface drying process / the lower surface drying process. Will be described. The processing of this flowchart is achieved by the control unit 18 executing the substrate processing program stored in the storage unit 19.

  First, the control unit 18 receives a recipe (setting information: electronic data) that describes the contents of a series of cleaning processing and drying processing (for example, the type of processing liquid and drying gas, supply flow rate, supply timing, supply time, etc.). Then, the setting information of (3) upper surface drying process / lower surface drying process in the recipe is referred to (step S101). As a method of accepting the recipe, there is a method in which the user selects what is held in the system or receives it from an external host computer via a network.

  Next, in the information referred in step S101, it is determined whether the flow rate of the drying gas to be supplied from the drying gas supply mechanism 74 to the lower surface is equal to or higher than the first flow rate (step S102). When the flow rate of the drying gas to be supplied is equal to or higher than the first flow rate, the recipe (setting information) is changed so that the drying gas (N2) is supplied from the gas supply port 61 to the upper surface of the wafer W (step S103). ). For example, the gas supply is continuously performed during the period in which the drying gas is supplied to the lower surface.

  On the other hand, if the flow rate of the drying gas to be supplied is not equal to or higher than the first flow rate, the recipe (setting information) is changed so that only the drying gas is supplied to the lower surface without supplying the drying gas to the upper surface.

  The recipe (setting information) is changed as described above, and the operation of this flowchart is terminated. Thereafter, each mechanism of the substrate processing apparatus is controlled based on the changed recipe (setting information), and (3) the upper surface drying process / the lower surface drying process is actually executed.

  Next, the experimental results when (3) the upper surface drying process / the lower surface drying process are performed will be described with reference to FIG.

  FIG. 7 shows (3) in the top surface drying process / bottom surface drying process, the number of rotations of the wafer W is kept constant at 2500 rpm, and the flow rate of the drying gas (N2) supplied to the top surface and the bottom surface is changed. It is a figure which shows the change of the dry state with the time passage of an upper surface and a lower surface. Here, “◯” and “x” in the frame indicate whether or not the drying of one surface of the wafer W is completed, and the portion in which the color in the frame is gray is the wafer. The time slot | zone when drying of both surfaces of W is not completed is shown.

  First, the conventional method, that is, the case where the drying gas is supplied only to the lower surface of the wafer W will be described. When the drying gas is supplied to the lower surface of the wafer W at a flow rate of 40 L / min, the drying of the lower surface of the wafer W is completed when 10 seconds elapses, whereas the upper surface of the wafer W is dried when 12 seconds elapses. Completed. When viewed on both surfaces of the wafer W, the drying is completed when 12 seconds have elapsed, and the difference in drying time between the upper surface and the lower surface of the wafer W is only 2 seconds, and a decrease in the drying capacity is hardly observed.

  However, when a drying gas is supplied to the lower surface of the wafer W at a flow rate of 60 L / min, drying is completed when 7 seconds have elapsed on the lower surface of the wafer W, whereas when 15 seconds have elapsed on the upper surface of the wafer W. Drying is complete. The difference in drying time between the upper surface and the lower surface of the wafer W is as large as 9 sec. The drying of the upper surface of the wafer W is completed later than in the case of 40 L / min, even though the lower surface of the wafer W has been dried earlier than in the case of 40 L / min. As a whole, when 15 seconds passed, the drying was completed, and a significant decrease in the drying capacity was observed. This is considered to be caused by the fact that when the supply amount of the drying gas to the lower surface is increased, the temperature of the upper surface of the substrate is also lowered by the amount of heat of vaporization when the lower surface is dried.

  Next, the case where the drying gas is supplied to both the upper surface and the lower surface of the wafer W will be described. A drying gas is supplied to the lower surface of the wafer W at a flow rate of 40 L / min, and a drying gas is supplied to the upper surface of the wafer W at a flow rate of 8 L / min. In this case, the drying of the lower surface of the wafer W is completed when 10 sec elapses, whereas the drying of the upper surface of the wafer W is completed when 6 sec elapses 4 sec earlier. When viewed on both sides, the drying process is completed when 10 seconds have elapsed. Moreover, compared with the case where the drying gas is supplied only to the upper surface, the drying process is completed by 2 seconds earlier, and the drying capacity is improved.

  On the other hand, the drying gas is supplied to the lower surface of the wafer at a flow rate of 60 L / min, and the drying gas is supplied to the upper surface of the wafer W at a flow rate of 8 L / min. In this case, the drying of the lower surface of the wafer W is completed when 7 seconds have elapsed, while the drying of the upper surface of the wafer W is also completed when 7 seconds have elapsed. Even when viewed on both sides, the drying process is completed when 7 seconds have elapsed, and the drying process is completed 8 seconds earlier than when the drying gas is supplied only to the upper surface, improving the drying capacity. ing.

This is because the drying performance is improved by supplying the drying gas to the upper surface, and the decrease in the drying performance due to the decrease in the temperature of the upper surface of the substrate is compensated, and the decrease in the temperature of the upper surface of the substrate is suppressed. it is conceivable that.
As described above, when the drying gas is supplied to the upper surface at a flow rate of 8 L / min when the flow rate of the drying gas to the lower surface of the wafer W is 40 L / min and 60 L / min, the improvement in the drying performance is confirmed. did it. However, on the other hand, there is also a demand for saving the flow rate of the drying gas as a whole system, and the standard of the required drying time varies depending on the processing.

  Therefore, in the control shown in FIG. 6A in the present embodiment, the drying gas is supplied to the upper surface when the flow rate of the drying gas to be supplied to the lower surface is equal to or higher than the predetermined flow rate. . If the upper limit of the drying time required for the treatment is 12 sec and the experimental result of FIG. 7 is reflected, the “first flow rate” of FIG. 6A can be set to 50 L / min. At this time, when the flow rate of the drying gas to be supplied is, for example, 60 L / min, in step S103, the drying gas (N2) is controlled to be supplied to the upper surface of the wafer W. For example, when the gas flow rate is 40 L / min, the drying gas (N2) is not supplied. By performing the above control, it is possible to achieve improvement in drying performance while suppressing consumption of the drying gas.

  As described above, according to the present embodiment, after the received recipe (setting information) performs the liquid processing on the upper surface and the lower surface of the wafer W, the processing for drying the upper surface and the lower surface of the wafer W in parallel is performed. , The setting information of the supply amount of the drying gas to the upper surface of the wafer W is changed according to the supply amount of the drying gas to the lower surface of the wafer W. As a result, it is possible to suppress a decrease in the drying performance of the upper surface of the wafer W caused by the supply of the drying gas to the lower surface of the wafer W, and to improve the drying performance of both surfaces of the wafer W as a whole. In particular, when the gas supply amount to the lower surface is greater than or equal to the first supply amount, gas is supplied to the upper surface of the wafer W, and when the gas supply amount to the lower surface is less than the first supply amount, The supply was not performed. Thereby, when the drying process of both surfaces of the wafer W is performed in parallel, the drying performance of both surfaces of the wafer W can be improved. Further, since the drying gas is supplied only when necessary, the amount of the drying gas used can be suppressed. In the present embodiment, the N 2 gas common to the purge gas is used as the drying gas. However, it is more effective when a high-cost gas such as dry air is supplied to the upper surface. When the gas supply amount to the lower surface is less than the first supply amount, not only the gas supply to the upper surface of the wafer W is not performed at all, but even the supply amount in the received setting information is reduced. If it does, the effect as a saving of the gas for drying can be acquired.

(Modification of the first embodiment)
The application example of the present invention is not limited to the operation of FIG. For example, as shown in FIG. 6B, the supply amount of the drying gas to the lower surface may be divided into a plurality of stages, and the supply amount of the drying gas on the upper surface may be changed corresponding to each of the stages.

  In the flowchart of FIG. 6B, step S201 performs the same processing as step S101. In step S202, the flow rate of the drying gas on the lower surface is compared with the first flow rate and the second flow rate set in advance. Here, the first flow rate is set to 50 L / min, and the second flow rate is set to 70 L / min.

  In step S202, when the flow rate of the drying gas is less than the second flow rate and greater than or equal to the first flow rate (for example, 60 L / min), the process proceeds to step S204, and the same process as step S103 in FIG. That is, the recipe (setting information) is changed so that the drying gas (N2) is supplied to the upper surface of the wafer W at a flow rate of 8 L / min. In step S202, if it is less than the first flow rate, the recipe (setting information) is changed so as not to supply the drying gas (N2).

  In step S202, when the flow rate of the drying gas is equal to or higher than the second flow rate (for example, 80 L / min) due to a request for further shortening the drying time (4 sec), the drying performance due to heat of vaporization on the upper surface In order to suppress this, the recipe (setting information) is changed so that the drying gas (N2) is supplied to the upper surface of the wafer W at a flow rate of 16 L / min (step). S203).

  By performing the above control, it is possible to cope with a case where a rapid drying process is required while suppressing the consumption of the drying gas. In this example, the supply amount is controlled in three stages. However, the present invention is not limited to this, and more stages may be provided as necessary. Further, the supply amount of the drying gas does not have to be the same as that in the first embodiment, and may be arbitrarily set.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The problem and purpose of this embodiment are the same as those of the first embodiment in that the lowering of the processing performance of the upper surface due to the supply of gas to the lower surface is the same as that of the first embodiment. It is different in that it is not a treatment but a cleaning treatment.

  The second embodiment shown in FIGS. 8 to 10 is different from the first embodiment in the configuration of the substrate holder 31. Further, the collection cup 50 is fixed at the upper position shown in FIG. 2 without moving up and down. Other configurations are substantially the same as those of the first embodiment shown in FIGS.

  In the second embodiment shown in FIG. 8 to FIG. 10, the same parts as those in the first embodiment shown in FIG. 1 to FIG. In this embodiment, the drying gas supply mechanism 72 and the drying gas supply mechanism 74 supply N2 gas as in the first embodiment, but the supply amount is different from that in the first embodiment. Each functions as a mechanism for supplying a purge gas.

  As shown in FIG. 8A, the substrate holding portion 31 in the present embodiment has a configuration in which a guide portion 801 is added to the holding member 31b in the first embodiment. The guide portion 801 is disposed so as to surround the entire circumference of the wafer W except for a passing position of the holding member 31b and an elevating member 806 described later. As shown in FIG. 8B, the guide portion 801 has an upper flat portion 801A and an inclined surface 801B inclined toward the center of the base plate 31a. The outer peripheral edge of the inclined surface 801B (boundary between the upper flat portion 801A and the inclined surface 801B) is located along the circumference of the first circle larger than the diameter of the wafer W, and the inner peripheral edge of the inclined surface 801B is It is located along the circumference of a second circle that is concentric with the circle 1 and smaller than the diameter of the wafer W. For this reason, when the wafer W is placed on the base plate 31a, the wafer W is supported by its end being in contact with the inclined surface 801B. At this time, the wafer W is separated from the upper surface of the base plate 31a.

  As shown in FIG. 9A, the holding members 31b are arranged at, for example, three locations with a gap between the lower peripheral edges of the base plate 31a. The holding member 31b has a structure in which a holding pin 802 that holds the wafer W and an operation piece 803 that moves the holding pin 802 between a holding position and a release position of the wafer W are connected via a rotating shaft 804. It has become.

  At the upper end portion of the holding pin 802, a contact surface is formed to contact the side peripheral surface of the wafer W, and the holding pin 802 is disposed with the contact surface facing inward in the radial direction of the base plate 31a. Yes. A base end portion of the holding pin 802 is attached to the base plate 31a via a rotation shaft 804, and the operating piece 803 extends obliquely downward from the rotation shaft 804 toward the inside in the radial direction of the base plate 31a.

  The rotating shaft 804 is urged in a direction in which the upper end portion of the holding pin 802 moves toward the inside in the radial direction of the base plate 31a, and the urging force sandwiches the wafer W between the holding pin 802 and the base plate. The wafer W is held horizontally with a gap between the upper surface of 31a. An annular push-up plate 805 connected to an elevating mechanism is provided at a position below each operating piece 803. As shown in FIG. 9B, when the push-up plate 805 is raised and the operating piece 803 is pushed up, the holding pin 802 rotates around the rotation shaft 804, and the holding pin 802 is directed outward in the radial direction of the base plate 31a. Is moved, the holding of the wafer W is released.

  Further, as shown in FIG. 8A, on the lower side of the peripheral edge of the base plate 31a, for example, three elevating members 806 made of a bar-like member extending in the vertical direction are spaced apart from each other along the circumferential direction of the base plate 31a. Is opened and placed. A support member 807 that transfers the wafer W between the substrate transfer device 17 and the holding member 31 b is provided at the upper end portion of each elevating member 806 via a coupling portion 808.

  Each support member 807 is arranged so as to extend upward from the upper part of the elevating member 806, and on the upper surface of the support member 807, an inclined surface 809 gradually lowering from the radially outer side to the inner side of the base plate 31a, 810 is formed. These inclined surfaces 809 and 810 are composed of a guide surface 809 and a support surface 810 having different inclination angles.

  The guide surface 809 having a large inclination angle is located radially outward as viewed from the base plate 31 a and plays a role of guiding the wafer W toward the inside of the region surrounded by the three support members 807. Further, the support surface 810 that is arranged inside the guide surface 809 and has a small inclination angle has the wafer W on the support member 807 so that the wafer W placed on the support member 807 is supported substantially horizontally by its own weight. It plays a role of guiding the movement (see FIG. 9A).

  The lower part of each elevating member 806 is connected to, for example, a common connecting plate formed in an annular shape, and each supporting member 807 is simultaneously raised and lowered by an equal distance by moving the connecting plate up and down by an elevating mechanism. be able to.

  As shown in FIG. 8 (a), notches 811 are provided at the peripheral edge of the base plate 31a corresponding to the position of the elevating member 806, and the base plate 31a rotating around the vertical axis The notch portion 811 stops at a position where it is disposed on the upper side of the elevating member 806. Each lifting member 806 passes through the notch 811 to project the support member 807 from the lower side to the upper side of the base plate 31 a, and the support member 807 is moved to the position where the wafer W is transferred to and from the substrate transfer device 17. It can be raised (see FIG. 9A).

  As shown in FIG. 9A, when the substrate transfer device 17 has transferred the wafer W to be processed, the substrate transfer device 17 stops at a position above the base plate 31a. Next, the elevating mechanism operates to raise the three elevating members 806 simultaneously. The raising / lowering member 806 is disposed at a position where it does not interfere with the substrate transfer device 17. When the substrate transfer device 17 raises the support surface 810 of the support member 807 higher than the height position at which the wafer W is held, The wafer W is delivered from the substrate transfer device 17 to the support member 807. The substrate transfer apparatus 17 that has delivered the wafer W to the support member 807 is then retracted from the processing unit 16.

  When the wafer W is delivered to the support member 807, the support member 807 is lowered from the support member 807 to a position where the wafer W is delivered to the holding pins 802 of the holding unit 31b. At this time, the holding pins 802 are waiting in a state of moving to the release position, and when the support member 807 is lowered to the delivery position, the wafer W is placed on the wafer support portion 801 (FIG. 9B). . Next, the push-up plate 805 is lowered, and the holding pins 802 are moved from the release position to the wafer holding position (FIG. 9C). As a result, the wafer W is held by the three holding pins 802 so as to be sandwiched from the side, and is held by the holding unit 31b with a gap between the wafer W and the upper surface of the base plate 31a. The elevating member 806 is lowered until the upper end of the support member 807 is positioned below the surface of the base plate 31a.

  As described above, the wafer W transferred by the substrate transfer device 17 is received by the support member 807 raised by the elevating member 806, and the elevating member 806 is lowered to smoothly place the wafer W on the support member 807 on the holding pins 802. In addition, the wafer W can be reliably held by the holding portion 31b.

  In the present embodiment, a cleaning process of the wafer W performed by the processing unit 16 having the above configuration will be described.

  FIG. 10 is a schematic diagram illustrating an operation state of the cleaning process using the brush according to the present embodiment. In the present embodiment, the radius of the wafer W is 150 mm, and the wafer W rotates at a predetermined rotation speed (for example, 1000 rpm).

  With respect to the upper surface, DIW is supplied from the processing liquid supply nozzle 62 to the center of the wafer W to form a liquid film on the substrate surface, a brush 63 is brought into contact with the upper surface of the substrate, and a horizontal scan is performed along the upper surface of the wafer W. By doing so, the substrate surface is physically cleaned. FIG. 10A shows a state in which the brush 63 is in contact with the center position (radius = 0 mm) of the wafer W, which is the scan start position. Thereafter, the brush 63 is moved in the outer peripheral direction of the wafer W at a predetermined speed, and the brush 63 scans to the end (radius = 147 mm) of the cleaning target range of the wafer W as shown in FIG. Exit.

  Regarding the lower surface, a drying gas supply mechanism 72 (second gas supply mechanism) is used to prevent the DIW from flowing into the lower surface during the period when DIW is supplied to the center of the wafer W from the processing liquid supply nozzle 62 on the upper surface. ) Is supplied from the gas passage 80 toward the center of the lower surface of the wafer W. However, in the present embodiment, the supply amount from when the DIW is started to be supplied from the processing liquid supply nozzle 62 until the brush 63 reaches a predetermined intermediate position (position of FIG. 10B: radius = 130 mm) The supply amount from the predetermined intermediate position (position in FIG. 10B: radius = 130 mm) to the end of the cleaning range of the wafer W (position in FIG. 10C: radius = 147 mm) is reduced. To control. The reason will be described below.

  In this embodiment, when the wafer W is appropriately held by the substrate holding unit 31, the lower surface of the wafer W contacts the upper flat portion 801A over the entire circumference as shown in FIGS. 8 (a) and 8 (b). Will be in touch. At this time, since the upper surface and the lower surface of the wafer W are physically blocked by the end portion of the wafer W, the DIW supplied to the upper surface during the cleaning process is the same as the structure of the substrate holding unit 31 of the first embodiment. In comparison, it becomes difficult to wrap around the lower surface of the wafer W. However, since the cutout portion 811 corresponding to the position where the elevating member 806 is disposed does not have the upper flat portion 801A, it is necessary to supply a purge gas to prevent the DIW from wrapping around from this position.

  In the present embodiment, there are only three openings defined by the respective cutout portions 811 so that the space between the lower surface of the wafer W, the space surrounded by the base plate 31a and the wafer support portion 801, and the outside thereof can be vented. For this reason, when a purge gas of a predetermined supply amount or more is supplied, this space becomes a positive pressure, and a force for pushing the wafer W upward works. Since the gas passage 80 for supplying the purge gas is located at the center position of the lower surface of the wafer W far from these openings, the magnitude of the force becomes maximum at the center position of the wafer W. According to the experiments by the inventors, when the supply amount of the purge gas is about 80 L / min or less, the downward force due to the weight of the wafer W is larger than the force that pushes the wafer W upward. It was found to bend into a concave shape. On the other hand, when the supply amount of the purge gas is about 80 L / min or more, the force that pushes the wafer W upward increases, so that the wafer W is bent into a convex shape.

  On the other hand, when attention is paid to the brush 63 in the present embodiment, the lower surface thereof is a flat surface, and is in contact with the wafer W by applying contact pressure due to its own weight during the cleaning process. Therefore, with respect to the convex wafer W, the brush 63 is less likely to come into contact with the wafer W as the scanning position advances toward the periphery, and a sufficient cleaning effect cannot be obtained. According to the experiments by the inventors, when the supply amount of the purge gas is 100 L / min and the wafer W is bent into a convex shape and the brush 63 is scanned, the convex shape is used until the radius of the wafer W = 130 mm. A sufficient cleaning effect was obtained even with this wafer W, but a sufficient cleaning effect was not obtained at the outer periphery.

  Therefore, when scanning the range where the radius of the wafer W is 130 mm to 147 mm, it is better not to bend the wafer W into a convex shape. In other words, in this range, the wafer W is kept flat (the supply amount of purge gas) = 75 L / min) or the wafer W may be bent into a concave shape (purge gas supply amount = 50 L / min). According to the experiments by the inventors, the cleaning effect is increased when the wafer W is bent into a concave shape rather than kept flat. One reason for obtaining this result is that the inward inclination angle of the wafer W increases toward the end, and the lateral driving force by scanning increases the contact pressure between the brush 63 and the wafer W. This is thought to be due to its action.

  In this embodiment, even when the peripheral portion is cleaned, the supply amount of the purge gas when the wafer W is bent into the concave shape is set to 50 L / min in order to prevent a certain amount of cleaning liquid from flowing around. The present invention is not limited to this as long as the supply amount of the purge gas is reduced while avoiding the convex shape. For example, if the cleaning effect at the end is prioritized over the prevention of the cleaning liquid from flowing in, the supply amount of the purge gas may be stopped (0 L / min), and the wafer W may be bent more concavely. On the other hand, if priority is given to preventing the cleaning liquid from flowing around the edge, the supply amount of the purge gas may be set to about 75 L / min so as to keep the wafer W flat.

  As described above, according to the present embodiment, the wafer W is held by the substrate holding part 31 having the guide part 801 arranged so as to surround the entire circumference of the wafer W, and the cleaning liquid is applied to the upper surface. When cleaning is performed by scanning the brush 63 from the center position to the end of the wafer W while supplying it, the purge gas is supplied at a first supply amount (for example, 100 L / min) up to a predetermined intermediate position (130 mm). The purge gas is supplied at a second supply amount (for example, 50 L / min) smaller than the first supply amount outside the predetermined intermediate position (130 mm). Accordingly, it is possible to prevent the cleaning liquid from flowing into the lower surface of the wafer W while maintaining the cleaning effect of the brush on the entire wafer W. Note that after the operation in the present embodiment is completed, a drying process accompanied with the setting change executed in the first embodiment may be performed.

16 Processing Unit 18 Control Unit 72 Drying Gas Supply Mechanism 74 Drying Gas Supply Mechanism

Claims (11)

A substrate processing apparatus for liquid processing a substrate by supplying a liquid to the substrate,
A first gas supply mechanism for supplying a drying gas to the upper surface of the liquid-treated substrate;
A second gas supply mechanism for supplying a drying gas to the lower surface of the liquid-treated substrate;
A control unit that controls processing using the first gas supply mechanism and the second gas supply mechanism based on the received setting information;
When the setting information includes a process of drying the upper surface and the lower surface of the liquid-treated substrate in parallel, the controller controls the amount of drying gas supplied to the lower surface of the substrate by the second gas supply mechanism. In response, the substrate processing apparatus changes setting information of the amount of drying gas supplied to the upper surface of the substrate by the first gas supply mechanism.   When the gas supply amount by the second gas supply mechanism is greater than or equal to the first supply amount, the control unit supplies gas to the upper surface of the substrate by the first gas supply mechanism, and by the second gas supply mechanism When the gas supply amount is not equal to or greater than the first supply amount, the setting information is changed so that the gas supply amount to the upper surface of the substrate by the first gas supply mechanism is less than the supply amount in the received setting information. The substrate processing apparatus according to claim 1, wherein:   The control unit changes the setting information so that the gas supply to the upper surface of the substrate by the first gas supply mechanism is not performed when the gas supply amount by the second gas supply mechanism is not greater than or equal to the first supply amount. The substrate processing apparatus according to claim 2.   When the gas supply amount by the second gas supply mechanism is equal to or greater than the second supply amount, the control unit performs gas supply to the upper surface of the substrate by the first gas supply mechanism at a third supply amount, and When the gas supply amount by the two gas supply mechanism is less than the second supply amount and not less than the first supply amount, the gas supply to the upper surface of the substrate by the first gas supply mechanism is performed at the fourth supply amount, and the second supply amount 2. The setting information is changed so that the gas is not supplied to the upper surface of the substrate by the first gas supply mechanism when the gas supply amount by the gas supply mechanism is less than the first supply amount. 2. The substrate processing apparatus according to 1. The liquid process is a cleaning process for cleaning by moving a brush along the upper surface of the substrate to which the liquid is supplied,
The second gas supply mechanism supplies a purge gas toward the center of the lower surface of the substrate during the cleaning process,
The substrate processing apparatus according to claim 1, wherein the control unit changes a supply amount of a purge gas of the second gas supply mechanism according to a position of the brush on the substrate. A substrate processing method for liquid processing a substrate by supplying a liquid to the substrate,
When receiving the setting information for performing the drying process on the upper surface and the lower surface of the liquid-treated substrate in parallel, the drying is performed on the upper surface of the substrate in the setting information according to the supply amount of the drying gas to the lower surface of the substrate. The substrate processing method characterized by changing the supply amount of the working gas.   When the gas supply amount is equal to or higher than the first supply amount, gas is supplied to the upper surface of the substrate. When the gas supply amount is not equal to or higher than the first supply amount, the gas supply amount to the upper surface of the substrate is The substrate processing method according to claim 6, wherein the substrate processing method is changed so as to reduce the supply amount in the received setting information.   The substrate processing method according to claim 7, wherein when the gas supply amount is not equal to or greater than the first supply amount, the setting information is changed so as not to supply gas to the upper surface of the substrate.   When the gas supply amount is greater than or equal to the second supply amount, gas supply to the upper surface of the substrate is performed at a third supply amount, and when the gas supply amount is less than the second supply amount and greater than or equal to the first supply amount, The gas is supplied to the upper surface of the substrate at a third supply amount, and when the gas supply amount is less than the first supply amount, control is performed so as not to supply the gas to the upper surface of the substrate. Item 7. The substrate processing method according to Item 6. The liquid process is a cleaning process in which a brush is moved along the upper surface of the substrate supplied with the liquid, and a purge gas is supplied toward the center of the lower surface of the substrate during the cleaning process.
The substrate processing method according to claim 6, wherein the supply amount of the purge gas is changed according to the position of the brush on the substrate.   A storage medium storing a program for executing the substrate processing method according to claim 6.

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