JP2018093146A - Substrate processing device, substrate processing method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate processing device arranged so that after supply of a rinse liquid to a lower face of a substrate being rotated, the liquid can be removed from a constituent part of the substrate processing device, which is located under the substrate, without exerting an adverse effect on a lower face of the substrate.SOLUTION: A substrate processing method comprises the steps of: supplying a rinse liquid to a lower face of a substrate (W) which is held and being rotated by substrate-holding rotating parts (3, 4) from a rinse liquid supplying part (20); then, supplying a dry gas from a gas supply part (21) with a liquid film of the rinse liquid retained all over the lower face of the rotating substrate to remove the liquid deposited on top end parts of a shaft member (5), e.g. a head part and lift pins (19, 19a); and then, removing the liquid film of the rinse liquid remaining on the lower face of the rotating substrate.SELECTED DRAWING: Figure 12

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for performing liquid processing on a lower surface of a substrate such as a semiconductor wafer.

  In a semiconductor device manufacturing process, a process of supplying a processing liquid to a substrate such as a semiconductor wafer and performing liquid processing such as cleaning and etching is frequently used. For example, as described in Patent Document 1, such a liquid process is performed by supplying a processing liquid to the front surface and / or back surface of the wafer while rotating the substrate by a spin chuck (substrate holding and rotating mechanism). The substrate processing apparatus is used.

  The apparatus described in Patent Document 1 has a non-rotating nozzle member provided below the wafer W near the rotation center of the spin chuck. When the wafer W is processed, the chemical liquid and the rinse liquid are sequentially discharged from the processing liquid discharge nozzle provided in the nozzle member, and after the discharge of the rinse liquid is completed, the wafer is shaken and dried. Since the nozzle member does not rotate even during the shake-off drying, the liquid, particularly the rinsing liquid, which has adhered to the surface of the nozzle member before the shake-off drying tends to remain as it is. Such residual rinse liquid may adversely affect the processing of the next wafer.

  In order to solve the above problem, in Patent Document 1, the drying gas is supplied along the surface of the nozzle member from the second discharge port provided in the gas discharge nozzle that discharges the drying gas from the first discharge port toward the wafer. The residual rinse liquid is blown off by spraying. However, in the technique of Patent Document 1, it has been found that if the wafer dries before the components of the substrate processing apparatus, the residual rinse liquid blown off from the components reattaches to the lower surface of the wafer. In this regard, there is room for further improvement in the technique of Patent Document 1.

JP 2010-186859 A

  An object of the present invention is to provide a technique for preventing liquid removed from components below a substrate from re-adhering to the substrate after supplying a rinse liquid to the lower surface of the rotating substrate.

  According to an embodiment of the present invention, a substrate support element that supports a substrate, and a rotating plate that is provided with the substrate support element and faces the substrate below the substrate, the substrate support element by the previous substrate support element. Is held by the substrate holding rotating unit, a substrate holding rotating unit that holds the substrate in a horizontal posture and rotates around a vertical axis, a shaft member having an upper end inserted in a hole provided in a central portion of the rotating plate, and the substrate holding rotating unit. A rinsing liquid supply unit for supplying a rinsing liquid to the lower surface of the substrate; a gas supply unit for supplying a drying gas to a space held by the substrate holding and rotating unit facing the lower surface of the substrate; and the substrate processing apparatus. A controller that controls the operation of the substrate, wherein the controller supplies the rinse liquid from the rinse liquid supply unit to the lower surface of the substrate held and rotated by the substrate holding and rotating unit, and then rotates. While maintaining the liquid film of the rinsing liquid over the entire lower surface of the substrate, the drying gas is supplied from the gas supply unit to remove the liquid adhering to the upper end portion of the shaft member, and then the lower surface of the rotating substrate There is provided a substrate processing apparatus that controls to remove the rinsing liquid remaining in the processing liquid.

  According to another embodiment of the present invention, there is provided a substrate processing method executed by a substrate processing apparatus, wherein the substrate processing apparatus is provided with a substrate support element that supports a substrate, and the substrate support element is provided. A rotation plate facing the substrate below the substrate, and a substrate holding rotation unit that holds the substrate in a horizontal posture by the substrate support element and rotates about the vertical axis, and is provided at the center of the rotation plate. A shaft member having an upper end inserted into the hole, a rinse liquid supply unit for supplying a rinse liquid to the lower surface of the substrate held by the substrate holding rotary unit, and the substrate held by the substrate holding rotary unit A gas supply unit that supplies a drying gas to a space that faces the lower surface of the substrate, and the substrate is rotated from the rinse liquid supply unit to the lower surface of the substrate that is held and rotated by the substrate holding and rotating unit. A liquid that is attached to the upper end of the shaft member by supplying a drying gas from the gas supply unit while maintaining a liquid film of the rinse liquid over the entire lower surface of the rotating substrate. There is provided a substrate processing method including removing a film of rinsing liquid remaining on the lower surface of the rotating substrate.

  According to still another embodiment of the present invention, when executed by a computer forming a control unit for controlling the operation of the substrate processing apparatus, the computer controls the substrate processing apparatus to perform the substrate processing method described above. There is provided a storage medium in which a program for executing is recorded.

  According to the embodiment of the present invention, the liquid adhered to the upper end portion of the shaft member is removed by the drying gas supplied from the gas supply unit in a state where the liquid film of the rinsing liquid is maintained over the entire lower surface of the substrate. Therefore, it is possible to prevent the liquid removed from the substrate lower component from reattaching to the substrate.

It is sectional drawing which shows schematic structure of the substrate processing apparatus which concerns on one Embodiment of this invention. It is sectional drawing of the nozzle member used for the substrate processing apparatus of FIG. It is a top view of the nozzle member used for the substrate processing apparatus of FIG. It is a figure which shows the state at the time of receiving a wafer in the substrate processing apparatus of FIG. In the substrate processing apparatus of FIG. 1, it is a figure which shows a state when implementing the chemical | medical solution washing | cleaning process. In the substrate processing apparatus of FIG. 1, it is a figure which shows a state when implementing the 1st step of the rinse process. In the substrate processing apparatus of FIG. 1, it is a figure which shows a state when implementing the 2nd step of a rinse process. In the substrate processing apparatus of FIG. 1, it is a figure which shows a state when the splash rinse process is implemented. FIG. 2 is a diagram showing a state when the first stage of a droplet removing process is performed in the substrate processing apparatus of FIG. 1. FIG. 2 is a diagram showing a state when a second stage of a droplet removing process is performed in the substrate processing apparatus of FIG. 1. FIG. 8 is a diagram showing a state when the third stage of the droplet removing process is performed in the substrate processing apparatus of FIG. 1. FIG. 8 is a diagram showing a state when the fourth stage of the droplet removing process is performed in the substrate processing apparatus of FIG. 1. In the substrate processing apparatus of FIG. 1, it is a figure which shows a state when the last rinse process is implemented. In the substrate processing apparatus of FIG. 1, it is a figure which shows a state when implementing the 1st step of a drying process. In the substrate processing apparatus of FIG. 1, it is a figure which shows a state when implementing the 2nd step of a drying process.

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

  The substrate processing apparatus 1 includes a chamber (not shown), a base plate 2 serving as a base of the chamber, a spin chuck (substrate holding mechanism) 3 provided in the chamber, a rotating mechanism 4 that rotates the spin chuck 3, The nozzle member 5 that discharges the processing liquid and the drying gas, the processing liquid supply mechanism 6 that supplies the processing liquid to the nozzle member 5, the gas supply mechanism 7 that supplies the drying gas to the nozzle member 5, and the waste liquid are received. A liquid receiving cup 8, a processing fluid supply mechanism 9 for supplying a processing fluid to the surface of the wafer W, and a control unit 10 are provided.

  The spin chuck 3 is provided on the rotary plate 11, the rotary shaft 12 connected to the center of the rotary plate 11, and the surface of the rotary plate 11, and the support pins 13 a that support the wafer W while floating from the rotary plate 11. And a guide ring 13 that is provided in an annular shape on the periphery of the rotary plate 11 and guides the wafer W. The spin chuck 3 holds a wafer W, which is a substrate to be processed, in a horizontal posture with the back surface facing downward. In this specification, the back surface of the wafer W means a surface on which a device of the wafer W is not formed, and the front surface of the wafer W means a surface on which a device of the wafer W is formed.

  The spin chuck 3 used in the present embodiment holds the wafer W by the differential pressure generated between the upper surface and the lower surface of the wafer W by rotating the wafer W while the wafer W is supported by the support pins 13a. It is configured. Instead of this type of spin chuck 3, a so-called mechanical chuck type spin chuck provided with a plurality of movable holding claws for clamping the peripheral edge of the wafer W can be used.

  The rotating mechanism 4 includes a motor 14, a pulley 15 provided at the rotating shaft of the motor 14 and the lower end of the rotating shaft 12, and a belt 16 that is stretched between the pulleys 15.

  The rotating shaft 12 has a cylindrical shape (hollow) and extends downward through the base plate 2. A funnel-shaped hole 11 a concentric with the hole 12 a communicating with the hole 12 a in the rotating shaft 12 is formed at the center of the rotating plate 11.

  As shown in FIGS. 2 and 3, the nozzle member 5 includes a head portion 19 and a shaft portion 18 that is continuous below the head portion 19 and extends vertically downward. The nozzle member 5 can be raised and lowered, but cannot rotate. When processing the wafer W, the shaft portion 18 is positioned inside the hole 12a in the rotating shaft 12, and the head portion 19 is positioned in the hole 11a.

  Inside the shaft portion 18 and the head portion 19, a processing liquid passage 18 a and a gas passage 18 b extend in the vertical direction. A processing liquid discharge nozzle 20 that discharges the processing liquid is provided at a position corresponding to the processing liquid passage 18a on the upper surface of the head portion 19, and a gas that discharges a drying gas is provided at a position corresponding to the gas passage 18b. A discharge nozzle 21 is provided.

  The processing liquid is supplied from the processing liquid supply mechanism 6 to the processing liquid passage 18a, and the drying gas is supplied from the gas supply mechanism 7 to the gas passage 18b.

  The processing liquid supply mechanism 6 has a processing liquid supply pipe 60 connected to the processing liquid flow path 18a. The treatment liquid supply pipe 60 is connected to a chemical liquid supply source 61a and a chemical liquid pipe 61c provided with an on-off valve 61b, and pure water connected to a pure water supply source 62a and provided with an on-off valve 62b. The pipe 62c and a valve drain pipe 63c to which the on-off valve 63b is connected are connected. The on-off valves 61b, 62b, and 63b may be integrated collective valves or may be three separate valves. Examples of the chemical used here include dilute hydrofluoric acid (DHF), which is an acid chemical, and ammonia perwater (SC1), which is an alkaline chemical.

  An opening / closing valve 64 is interposed in the processing liquid supply pipe 60. A flow control valve may be provided on the upstream side of the on-off valve 64 of the processing liquid supply pipe 60. A nozzle drain pipe 66 branches from the processing liquid supply pipe 60 at a branch point 65 set upstream of the on-off valve 64 of the processing liquid supply pipe 60. An opening / closing valve 67 is interposed in the nozzle drain pipe 66.

  The gas supply mechanism 7 has a gas supply pipe 71 whose downstream end is connected to the gas flow path 18 b and whose upstream end is connected to the gas supply source 70. An opening / closing valve 72 is interposed in the gas supply pipe 71. A flow control valve may be provided in the gas supply pipe 71.

  The processing liquid discharge nozzle 20 has a processing liquid discharge port 20a through which the processing liquid supplied from the processing liquid flow path 18a is discharged upward. The gas discharge nozzle 21 has one first gas discharge port 21 a that discharges a drying gas, for example, nitrogen gas, supplied from the gas flow path 18 b upward, and a drying gas on the upper surface of the head portion 19. And a plurality of (eight in the illustrated example) second gas discharge ports 21b that discharge radially in the horizontal direction.

  Three lift pins 19 a are provided on the upper surface of the head portion 19 of the nozzle member 5. A cylinder mechanism 23 is connected to the lower end portion of the nozzle member 5 via a connecting member 22. By raising the nozzle member 5 by the cylinder mechanism 23, the wafer W can be lifted via the lift pins 19a.

  The liquid receiving cup 8 surrounds the peripheral edge of the wafer W held on the rotating plate 11 and receives the processing liquid scattered from the wafer W. A drain port 8a is formed at the bottom of the liquid receiving cup 8, and a drain pipe 32 extends downward from the drain port 8a.

   The processing fluid supply mechanism 9 includes at least one processing fluid nozzle 33 and a processing fluid pipe 34 that supplies the processing fluid from the processing fluid supply source 35 to the processing fluid nozzle 33. The processing fluid supplied to the surface of the wafer W by the processing fluid supply mechanism 9 includes a chemical solution such as DHF and SC1, a rinsing solution such as pure water or functional water, a two-fluid solution of misted rinsing solution and gas, IPA Examples thereof include a drying solvent such as nitrogen gas and a drying gas such as nitrogen gas. The processing fluid nozzle 33 can be scannable. When pure water and chemical liquid are supplied to the processing fluid nozzle 33, they can be supplied from the chemical liquid supply source 61a and the pure water supply source 62a.

  As schematically illustrated in FIG. 1, the control unit 10 includes a controller 41, a user interface 42, and a storage unit 43. The controller 41 includes a microprocessor (computer), and controls each component of the substrate processing apparatus 1, such as the on-off valves 26, 29, 31, 36, the motor 14, the cylinder mechanism 23, and the like.

  The user interface 42 is connected to the controller 41 and includes a keyboard on which an operator inputs commands and the like to manage the substrate processing apparatus 1, a display that visualizes and displays the operating status of the substrate processing apparatus 1, and the like.

  The storage unit 43 is also connected to the controller 41, and a program for controlling the control target of each component of the substrate processing apparatus 1 and a program for causing the substrate processing apparatus 1 to perform a predetermined process, that is, a processing recipe, are included therein. Stored. The processing recipe is stored in a storage medium (not shown) in the storage unit 43. The storage medium may be a fixed medium such as a hard disk or a portable medium such as a CDROM, DVD, or flash memory. Moreover, you may make it transmit a recipe suitably from another apparatus via a dedicated line, for example.

  The controller 41 performs a predetermined process under the control of the controller 41 by calling and executing a predetermined process recipe from the storage unit 43 according to an instruction from the user interface 42 or the like as necessary.

  Next, a procedure for performing liquid processing on the wafer W by the substrate processing apparatus 1 will be described.

  First, a transfer arm (not shown) holding the wafer W enters the chamber, passes the wafer W to the lift pins 19a of the head portion 19 of the nozzle member 5 at the raised position, and then exits the chamber. This state is shown in FIG. Next, the nozzle member 5 is lowered, and in the process, the wafer W is transferred to the support pins 13 a while being positioned by the guide ring 13. This state is shown in FIG.

  Next, the rotation mechanism 4 is activated to start the rotation of the wafer W. The rotation of the wafer W is continued until a series of processing on the wafer W is completed.

[Chemical cleaning process]
Next, as shown in FIG. 5, the on-off valves 61b, 64 are opened with the on-off valves 62b, 63b, 67, 72 closed. As a result, the chemical liquid, here DHF, is discharged from the processing liquid discharge port 20 a provided in the processing liquid discharge nozzle 20 of the nozzle member 5 toward the center of the back surface (lower surface) of the wafer W. The DHF flows while spreading from the center to the periphery of the wafer W, and a DHF liquid film is formed on the entire back surface of the wafer W. Thereby, the back surface of the wafer W is cleaned with a chemical solution. The number of rotations of the wafer W at this time is, for example, about 1600 rpm.

  In FIG. 5 to FIG. 15, the closed on-off valve is painted black, and the arrow indicates the flowing (moving) fluid.

[First stage of rinsing process]
Next, while maintaining the rotation speed of the wafer W, the on-off valve 61b is closed and the on-off valve 62b is opened as shown in FIG. Thereby, pure water (DIW) as a rinsing liquid is discharged from the processing liquid discharge port 20a toward the center of the back surface (lower surface) of the wafer W. The DIW flows while spreading from the center of the wafer W toward the peripheral edge, and a liquid film of DIW is formed on the back surface of the wafer W. As a result, the DHF remaining on the back surface of the wafer W and the reaction product due to the chemical cleaning are washed away by the DIW.

[Second stage of rinsing process]
Next, the rotational speed of the wafer W is reduced to, for example, about 1200 rpm, and the on-off valve 63b is opened as shown in FIG. Thereby, a part of DIW supplied from the pure water supply source 62a flows into the valve drain pipe 63c, and the DHF remaining in the processing liquid supply pipe 60 near the on-off valves 61b, 62b, 63b is substantially reduced. Completely removed. Also at this time, DIW is continuously discharged from the processing liquid discharge port 20a toward the back surface of the wafer W.

[Splash rinse process]
Next, in a state where the rotational speed of the wafer W is maintained and DIW is discharged from the discharge port 20a toward the back surface of the wafer W, the on-off valve 63b is closed as shown in FIG. The on-off valve 72 of 71 is opened. Thereby, nitrogen gas is injected from the 1st gas discharge port 21a of the gas discharge nozzle 21, and the 2nd gas discharge port 21b. Nitrogen gas injected from one of the eight second gas discharge ports 21b directly collides with the flow of DIW discharged from the discharge port 20a and before reaching the wafer W, thereby causing a mist of DIW ( Microdroplets) are formed. The mist of DIW drifts in the space between the back surface of the wafer W and the upper surface of the rotating plate 11 and falls on the upper surface of the head portion 19 of the nozzle member 5 and the surface of the lift pins 19a, thereby cleaning these members. At this time, the DIW mist falls on the upper surface of the rotating plate 11 and the surface of the support pin 13a, and these members are also cleaned.

  During the splash rinsing process, the back surface of the wafer W is wet by the DIW mist drifting in the space between the back surface of the wafer W and the top surface of the rotating plate 11, so that the back surface of the wafer W is not dried. In addition, when the upper surface of the head part 19 and the surface of the lift pin 19a are not dirty (for example, when it is only wet with DIW), this splash rinsing process may be omitted.

[First stage of the droplet removing process (gas blowing stage)]
Next, while maintaining the rotation speed of the wafer W and with the nitrogen gas being injected from the gas discharge nozzle 21, as shown in FIG. 9, the on-off valve 62b is closed and DIW is discharged from the discharge port 20a. To stop. Thereby, the liquid adhering to the upper surface of the head part 19 of the nozzle member 5 and the lift pin 19a by the nitrogen gas sprayed from the second gas discharge port 21b of the gas discharge nozzle 21, here, this is a splash rinse process. The attached DIW droplets are blown away.

  If the first stage of the droplet removing process is continued for a long time, the centrifugal force acting on the DIW existing at the center of the back surface of the wafer W and the nitrogen gas blown from the first gas discharge port 21a to the center of the back surface of the wafer W will be described. Due to the influence, the central portion of the rear surface of the wafer W is dried (that is, the liquid film of DIW covering the central portion of the rear surface of the wafer W disappears), and the rear surface of the wafer W may be exposed. If the DIW mist blown off from the head portion 19 and the lift pins 19a adheres to the exposed central portion of the back surface of the wafer W, there is a risk of forming particles. For this reason, the first stage of the droplet removing process is completed in a relatively short time, for example, about 2 seconds, and the process proceeds to the second stage of the droplet removing process.

[Second Stage of Droplet Removal Process (Liquid Film Recovery Stage)]
Next, while maintaining the rotation speed of the wafer W, as shown in FIG. 10, the on-off valve 72 of the gas supply pipe 71 is closed to stop the injection of nitrogen gas from the gas discharge nozzle 21, and the on-off valve 62b is turned on. Open and discharge DIW from the discharge port 20a again. As a result, the thickness of the DIW liquid film on the back surface of the wafer W, which has become thin at the end of the first stage of the droplet removal process, increases again. In the second stage of the droplet removal process, the thickness of the liquid film is restored to the extent that the DIW liquid film on the back surface of the wafer W is not lost in the third and fourth stages of the subsequent droplet removal process. What is necessary is just to perform time required for making it, for example, about 1-2 seconds.

[The third stage of the droplet removal process (nozzle drain stage)]
Next, with the rotation speed of the wafer W maintained and the injection of nitrogen gas from the gas discharge nozzle 21 stopped, as shown in FIG. 11, the on-off valve 62b is closed and the discharge port 20a is closed. Stop DIW discharge. At approximately the same time as closing the on-off valve 62b (may be slightly more or less), the on-off valve 67 of the nozzle drain pipe 66 is opened. As a result, DIW filling the processing liquid flow path 18a and the processing liquid supply pipe 60 flows into the nozzle drain pipe 66 located at a low position due to the influence of gravity, and as a result, the processing liquid flow path near the discharge port 20a. There will be no DIW in 18a.

  If DIW is present in the vicinity of the discharge port 20a, the DIW in the vicinity of the discharge port 20a is sucked out by nitrogen gas injected from the second gas discharge port 21b in the fourth stage of the next droplet removal process. As a result, the mist is formed, drifts in the vicinity of the head portion 19, and may adhere to the upper surface of the head portion 19 of the nozzle member 5 and the lift pin 19a. By performing the third stage of the droplet removing process, such a phenomenon can be prevented. The third stage of the droplet removing process may be performed for a time as short as possible, for example, about 1 second, as long as the above phenomenon can be prevented from the viewpoint of preventing the central portion of the back surface of the wafer W from drying.

[Fourth Stage of Droplet Removal Process (Gas Blow Stage)]
Next, as shown in FIG. 12, the opening / closing valve 67 of the nozzle drain pipe 66 and the opening / closing of the processing liquid supply pipe 60 are maintained while maintaining the rotational speed of the wafer W and stopping the DIW discharge from the discharge port 20a. The valve 64 is closed, and the open / close valve 72 of the gas supply pipe 71 is opened to inject nitrogen gas from the first gas discharge port 21 a and the second gas discharge port 21 b of the gas discharge nozzle 21. As a result, similarly to the first stage of the droplet removing process, the nitrogen gas injected from the second gas discharge port 21b of the gas discharge nozzle 21 adheres to the upper surface of the head portion 19 of the nozzle member 5 and the lift pin 19a. The DIW mist is blown away. Similar to the first stage of the droplet removing process, the fourth stage of the droplet removing process is completed in a relatively short time, for example, about 2 seconds, in order to prevent the central portion of the back surface of the wafer W from drying.

  By closing the on-off valve 64 of the processing liquid supply pipe 60 in the fourth stage of the droplet removing process, DIW remaining in the processing liquid supply pipe 60 is jetted from the second gas discharge port 21b. It is possible to prevent the nitrogen gas from being drawn out and flowing out from the discharge port 20a.

[Repeating Step 2 to Step 4 of Droplet Removal Process]
Thereafter, the second to fourth stages of the droplet removing process described above are sequentially repeated until the mist of DIW adhering to the upper surface of the head portion 19 of the nozzle member 5 and the lift pin 19a is sufficiently removed. To do. When shifting from the fourth stage to the second stage, the on-off valve 64 of the processing liquid supply pipe 60 is opened.

[Final rinse process]
If the DIW mist adhering to the upper surface of the head portion 19 and the lift pins 19a is sufficiently removed after the completion of the fourth stage of the Nth (N is a natural number) droplet removing process, the rotational speed of the wafer W 13, the on-off valve 72 of the gas supply pipe 71 is closed to stop the injection of nitrogen gas from the gas discharge nozzle 21, and the on-off valve 64 and the on-off valve 62b are opened to open the discharge port, as shown in FIG. DIW is discharged again from 20a, and the final rinsing process on the back surface of the wafer W is performed. As a result, even if particles rolled up by nitrogen gas blowing in the droplet removing process are present in the liquid film on the back surface of the wafer W, such particles can be removed. The execution time of the final rinsing step is arbitrary, but is about 9 seconds, for example.

[First stage of drying process (shaking off drying stage)]
Next, the number of rotations of the wafer W is increased to about 2200 rpm, for example, so that the drying can be efficiently performed, and the injection of nitrogen gas from the gas discharge nozzle 21 is stopped. As shown in FIG. 4, the on-off valve 62b is closed to stop the DIW discharge from the discharge port 20a. The first stage of the drying process is performed for about 15 seconds, for example. During the first stage of the drying process, the on-off valve 67 of the nozzle drain pipe 66 is opened, and DIW does not exist in the processing liquid passage 18a near the discharge port 20a, as in the third stage of the droplet removing process. Like that.

[Second stage of drying process (gas blowing stage)]
In the first stage of the drying process, first, a substantially circular dry area DA (also referred to as a “dry core”) in which a DIW liquid film does not exist at the center of the back surface of the wafer W is generated. W gradually spread toward the periphery. After the dry region is generated at the center of the back surface of the wafer W at the earliest, preferably after the DIW liquid film disappears from the entire back surface of the wafer W, the on-off valve 72 of the gas supply pipe 71 is opened to open the first of the gas discharge nozzle 21. Nitrogen gas is injected from the gas discharge port 21a and the second gas discharge port 21b. Thereby, the space near the back surface of the wafer W becomes a low humidity and low oxygen concentration atmosphere, and the drying of the wafer W (removal of moisture remaining on the wafer surface) is promoted. At this time as well, it is preferable to close the on-off valve 64 of the treatment liquid supply pipe 60 in the same manner as the fourth stage of the droplet removing process in order to prevent the DIW from flowing out from the discharge port 20a.

  Note that when nitrogen gas is jetted with the DIW liquid film remaining in the center of the back surface of the wafer, the DIW on the back surface of the wafer W becomes droplets by nitrogen gas blown to the wafer W from the first gas discharge port 21a. And the liquid droplets adhered to the upper surface of the head portion 19 and the lift pins 19a of the nozzle member 5 and the liquid droplets adhering to the upper surface of the head portion 19 and the lift pins 19a may be returned to the wafer W and contaminate the wafer W. There is. Therefore, at the earliest start of the nitrogen gas injection, the DIW liquid film starts from the region on the back surface of the wafer W where the nitrogen gas injected from the gas discharge nozzle 21, particularly the first gas discharge port 21 a collides vigorously. It is preferable to carry out after disappearance.

  Considering the above, the first stage of the drying process is performed for about 15 seconds, for example. In addition, although the execution time of the 2nd step of a drying process is arbitrary, it is about 10 second, for example. After the completion of the second stage of the drying process, the rotation of the wafer W is stopped, thereby completing a series of processes for one wafer.

  Although detailed description is omitted in this specification, it is also possible to perform the cleaning process on the front surface of the wafer W in parallel with the cleaning process on the back surface of the wafer W using the processing fluid supply mechanism 9. .

  According to the above embodiment, in the liquid film removing step, the nozzle which is a component below the substrate by the drying gas supplied from the gas discharge nozzle 21 in a state where the liquid film of the rinse liquid is maintained over the entire lower surface of the wafer W. Since the liquid adhering to the upper surface of the head portion 19 of the member 5 and the lift pins 19a is removed, it is possible to prevent the liquid removed from the components below the substrate from reattaching to the wafer W.

  In the above embodiment, the number of the second gas discharge ports 21b of the gas discharge nozzle 21 is eight. However, if the upper surface of the head portion 19 of the nozzle member 5 and the droplets of the lift pins 19a can be removed effectively, The number is not limited.

  In the above embodiment, the first gas ejection port 21a that ejects nitrogen gas toward the center of the back surface of the wafer W and the second gas ejection port 21b that ejects nitrogen gas along the upper surface of the head portion 19 are the same gas. Although it was provided in the discharge nozzle 21, it is not limited to this. The first gas discharge port 21a and the second gas discharge port 21b may be provided in separate nozzle bodies.

In the above embodiment, the drying gas is supplied from the common gas supply mechanism 7 to the first gas discharge port 21a and the second gas discharge port 21b. However, the present invention is not limited to this. You may provide two independent gas supply mechanisms which supply gas separately to the 1st gas discharge port 21a and the 2nd gas discharge port 21b. In this way, the following requirements can be satisfied.
(1) In the splash rinsing process, it is not necessary to inject gas from the first gas discharge port 21a. In the drying process, gas injection from the second gas discharge port 21b is not necessary. It is preferable from the viewpoint of running cost reduction to suppress unnecessary gas consumption.
(2) In the first stage and the fourth stage of the droplet removal process, it is preferable that the central portion of the back surface of the wafer W is not dried at an early stage. Therefore, gas is not injected from the first gas discharge port 21a. Better.

  In the above embodiment, the substrate to be processed is a semiconductor wafer. However, if the substrate is a substrate whose lower surface (downward surface) is processed while being rotated around the vertical axis in a horizontal posture, other substrates such as a glass substrate and a ceramic substrate are used. A substrate made of a material may be used. Further, the surface to be faced down during processing may be the front surface (surface on which a device is formed) or the back surface of the wafer W.

  The rinse liquid used for the treatment is not limited to pure water (deionized water (DIW)), but may be functional water (for example, carbon dioxide gas or hydrogen dissolved in DIW).

  The liquid removed from the upper surface of the head portion 19 of the nozzle member 5 and the lift pins 19a in the fourth stage (gas blowing stage) of the droplet removing process is DIW adhered in the splash rinse process, but is not limited thereto. Instead, it may contain a liquid adhering before the execution of the splash rinse step.

W substrate (semiconductor wafer)
3,4 Substrate holding rotating part (spin chuck and rotating mechanism)
5 Shaft member (nozzle member)
10 Control Unit 11 Rotating Plate 13a Substrate Support Element (Support Pin)
19, 19a Substrate lower component, non-rotating member (head and lift pin)
20 Rinse solution supply unit (treatment solution discharge nozzle)
21 Gas supply part (gas discharge nozzle)
21a First discharge port 21b Second discharge port 23 Lifting mechanism (cylinder mechanism)

Claims (13)

A substrate supporting element that supports the substrate; and a rotating plate that is provided with the substrate supporting element and faces the substrate below the substrate, and holds the substrate in a horizontal posture by the previous substrate supporting element and around the vertical axis A substrate holding and rotating unit that rotates
A shaft member having an upper end inserted into a hole provided in the center of the rotating plate;
A rinsing liquid supply unit for supplying a rinsing liquid to the lower surface of the substrate held by the substrate holding rotating unit;
A gas supply unit that supplies a drying gas to a space that is held by the substrate holding rotation unit and that faces the lower surface of the substrate;
A control unit for controlling the operation of the substrate processing apparatus,
The control unit supplies the rinse liquid from the rinse liquid supply unit to the lower surface of the substrate held and rotated by the substrate holding rotation unit, and then forms a liquid film of the rinse liquid over the entire lower surface of the rotating substrate. While maintaining, the drying gas is supplied from the gas supply unit to remove the liquid adhering to the upper end portion of the shaft member, and then the rinsing liquid of the processing liquid remaining on the lower surface of the rotating substrate is removed. A substrate processing apparatus to be controlled.   When the controller removes the liquid film of the rinsing liquid remaining on the lower surface of the substrate, the rinsing liquid remaining in at least the central portion of the lower surface of the substrate without supplying the drying gas from the gas supply unit. The substrate processing apparatus according to claim 1, wherein the liquid film is removed, and thereafter, the drying gas is controlled to be supplied from the gas supply unit.   Supplying the drying gas from the gas supply unit while maintaining a liquid film of the rinse liquid over the entire lower surface of the substrate supplies the rinse liquid from the rinse liquid supply unit to the lower surface of the substrate, and then the rinse The drying gas is supplied from the gas supply unit in a state where the supply of the liquid is stopped, and then the rinsing liquid is supplied from the rinsing liquid supply unit before the liquid film of the rinsing liquid disappears on at least a part of the lower surface of the substrate. The substrate processing apparatus according to claim 1, comprising supplying.   A rinsing liquid nozzle that constitutes the rinsing liquid supply part and a gas nozzle that constitutes the gas supply part are provided at the upper end part of the shaft member, and the liquid adhered to the upper surface of the upper end part of the shaft member by the gas nozzle is provided. The substrate processing apparatus according to claim 1, which is removed.   The gas nozzle is for drying in a direction along the upper surface of the upper end portion of the shaft member, and a first discharge port for injecting a drying gas toward the central portion of the lower surface of the substrate held by the substrate holding rotating unit. 5. The substrate according to claim 4, further comprising: a second ejection port that ejects gas, wherein the liquid adhering to the upper surface of the upper end portion of the shaft member is removed by the drying gas ejected from the second ejection port. Processing equipment. A lifting mechanism for lifting and lowering the shaft member;
A lift pin that supports the substrate when the substrate is carried into the substrate holding rotation unit is provided at an upper end portion of the shaft member, and removing the liquid adhering to the lower component of the substrate is a function of the lift pin. The substrate processing apparatus according to claim 1, comprising removing the attached liquid. A substrate processing method executed by a substrate processing apparatus, wherein the substrate processing apparatus comprises:
A substrate supporting element that supports the substrate; and a rotating plate that is provided with the substrate supporting element and faces the substrate below the substrate, and holds the substrate in a horizontal posture by the previous substrate supporting element and around the vertical axis A substrate holding and rotating unit that rotates
A shaft member having an upper end inserted into a hole provided in the center of the rotating plate;
A rinsing liquid supply unit for supplying a rinsing liquid to the lower surface of the substrate held by the substrate holding rotating unit;
A gas supply unit that supplies a drying gas to a space that is held by the substrate holding rotation unit and that faces the lower surface of the substrate;
In what has
Supplying a rinsing liquid from the rinsing liquid supply section to the lower surface of the substrate held and rotated by the substrate holding rotation section;
Thereafter, supplying a drying gas from the gas supply unit while maintaining a liquid film of the rinsing liquid over the entire lower surface of the rotating substrate, and removing the liquid adhering to the upper end of the shaft member;
Thereafter, removing the liquid film of the rinsing liquid remaining on the lower surface of the rotating substrate, the substrate processing method.   When removing the liquid film of the rinsing liquid remaining on the lower surface of the substrate, the liquid film of the rinsing liquid remaining on at least the central portion of the lower surface of the substrate is removed without supplying the drying gas from the gas supply unit. Then, the substrate processing method according to claim 7, wherein the drying gas is supplied from the gas supply unit.   Supplying the drying gas from the gas supply unit while maintaining a liquid film of the rinse liquid over the entire lower surface of the substrate supplies the rinse liquid from the rinse liquid supply unit to the lower surface of the substrate, and then the rinse The drying gas is supplied from the gas supply unit in a state where the supply of the liquid is stopped, and then the rinsing liquid is supplied from the rinsing liquid supply unit before the liquid film of the rinsing liquid disappears on at least a part of the lower surface of the substrate. The substrate processing method according to claim 7, comprising supplying.   A rinsing liquid nozzle that constitutes the rinsing liquid supply part and a gas nozzle that constitutes the gas supply part are provided at the upper end part of the shaft member, and the liquid adhered to the upper surface of the upper end part of the shaft member by the gas nozzle is provided. The substrate processing method of Claim 9 which removes.   The gas nozzle is for drying in a direction along the upper surface of the upper end portion of the shaft member, and a first discharge port for injecting a drying gas toward the central portion of the lower surface of the substrate held by the substrate holding rotating unit. 11. The substrate according to claim 10, further comprising: a second ejection port that ejects gas, wherein the liquid adhering to the upper surface of the upper end portion of the shaft member is removed by the drying gas ejected from the second ejection port. Processing method. The substrate processing apparatus further comprises an elevating mechanism for elevating the shaft member,
A lift pin that supports the substrate when the substrate is carried into the substrate holding rotation unit is provided at an upper end portion of the shaft member, and removing the liquid adhering to the lower component of the substrate is a function of the lift pin. The substrate processing method according to claim 7, comprising removing the attached liquid.   The substrate processing according to any one of claims 7 to 12, wherein when executed by a computer constituting a control unit for controlling the operation of the substrate processing apparatus, the computer controls the substrate processing apparatus. A storage medium on which a program for executing the method is recorded.

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