JP2020136438A - Substrate treatment apparatus and substrate treatment method - Google Patents

Abstract

To suppress generation of particles derived from a drying liquid.SOLUTION: A substrate treatment apparatus includes: a substrate holding unit that holds a substrate; a rotation driving unit that rotationally drives the substrate holding unit; a rinse liquid supply unit; a drying liquid supply unit; an ultraviolet irradiation unit; and a control unit that controls the rotation driving unit, the rinse liquid supply unit, the drying liquid supply unit, and the ultraviolet irradiation unit. The control unit causes the rinse liquid supply unit to supply a rinse liquid to a rotating substrate; then causes the drying liquid supply unit to supply the drying liquid to a central portion of the substrate; after that, while causing the drying liquid supply unit to expand a drying region to be formed on the substrate from the central portion to a peripheral portion of the substrate, by causing the drying liquid supply unit to move a liquid landing position of the drying liquid from the central portion to the peripheral portion, causes the ultraviolet irradiation unit to irradiate the drying region on the substrate with ultraviolet rays. At this time, the ultraviolet irradiation unit moves the irradiation position with the ultraviolet ray from the central portion to the peripheral portion of the substrate, while keeping a distance from a rotation center of the substrate to the liquid landing position of the drying liquid larger than a distance from the rotation center of the substrate to the irradiation position with the ultraviolet ray.SELECTED DRAWING: Figure 2

Description

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

In the manufacture of semiconductor devices, substrates such as semiconductor wafers are subjected to various chemical treatments for etching, cleaning, and the like. The chemical treatment can be performed by a single-wafer processing apparatus equipped with a spin chuck that holds the substrate in a horizontal position and rotates it around the vertical axis, and a nozzle that supplies the chemical liquid to the rotating substrate. After the chemical treatment, the substrate is rinsed and dried. During the drying process, IPA (isopropyl alcohol) is supplied to the substrate as a drying liquid for improving the drying performance.

Japanese Unexamined Patent Publication No. 2013-115370

The present disclosure provides a technique for suppressing the generation of particles derived from a dry liquid.

The substrate processing apparatus according to one embodiment includes a substrate holding portion that holds a substrate, a rotational driving portion that rotationally drives the substrate holding portion, and a rinse liquid supply that supplies a rinse liquid to the substrate held by the substrate holding portion. The unit, the drying liquid supply unit that supplies the drying liquid to the substrate held by the substrate holding unit, the ultraviolet irradiation unit that irradiates the substrate held by the substrate holding unit with ultraviolet rays, the rotation driving unit, and the rinse. The control unit includes a liquid supply unit, a drying liquid supply unit, and a control unit that controls the ultraviolet irradiation unit. The control unit is such that the rinse liquid is supplied to a rotating substrate while being held by the substrate holding unit. After being supplied, the drying liquid is supplied to the central portion of the substrate by the drying liquid supply unit, and then the drying liquid is formed on the substrate by moving the landing position of the drying liquid from the central portion to the peripheral portion of the substrate. While expanding the region from the central portion to the peripheral portion, the ultraviolet irradiation portion irradiates the substrate with ultraviolet rays, and at this time, the distance from the rotation center of the substrate to the landing position of the drying liquid is the rotation center of the substrate. The ultraviolet irradiation position is moved from the central portion to the peripheral portion of the substrate while maintaining the distance from the ultraviolet ray irradiation position to be larger than the distance from the ultraviolet ray irradiation position.

According to the present disclosure, it is possible to suppress the generation of particles derived from the dry liquid.

It is a vertical sectional side view of the substrate processing apparatus which concerns on one Embodiment. It is a schematic vertical sectional view which shows the structure of the processing unit of the substrate processing apparatus of FIG. It is a schematic plan view which shows an example of the planar positional relationship between a wafer and a nozzle arm. It is a schematic plan view which shows another example of the planar positional relationship between a wafer and a nozzle arm. It is a figure which shows an example of the structure of the integrated UV lamp and a gas nozzle, the upper part is a schematic bottom view, and the lower part is a schematic cross-sectional view. FIG. 6 is a schematic bottom view showing another example of an integrated UV lamp and gas nozzle. FIG. 6 is a schematic bottom view showing another example of an integrated UV lamp and gas nozzle. It is a schematic side view explaining an example of the flow of the drying liquid replacement process and the drying process among the process of liquid treatment. It is the schematic perspective view explaining an example of the state in the middle of a drying process. It is a table explaining the test result.

An embodiment of the substrate processing apparatus will be described with reference to the accompanying drawings.

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, Y-axis, and Z-axis that are orthogonal to each other are defined, and the positive direction of the Z-axis is defined as the vertically upward direction.

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

The loading / unloading station 2 includes a carrier mounting section 11 and a transport section 12. A plurality of substrates, and in the present embodiment, a plurality of carriers C for accommodating a semiconductor wafer (hereinafter referred to as wafer W) in a horizontal state are mounted on the carrier mounting portion 11.

The transport section 12 is provided adjacent to the carrier mounting section 11, and includes a substrate transport device 13 and a delivery section 14 inside. The substrate transfer device 13 includes a wafer holding mechanism for holding the wafer W. Further, the substrate transfer device 13 can move in the horizontal direction and the vertical direction and can rotate around the vertical axis, and transfers the wafer W between the carrier C and the delivery portion 14 by using the wafer holding mechanism. Do.

The processing station 3 is provided adjacent to the transport 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 both sides of the transport unit 15.

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

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

Further, the substrate processing system 1 includes a control device 4. The control device 4 is, for example, a computer, and includes a control unit 18 and a storage unit 19. The storage unit 19 stores programs that control 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.

The program may be recorded on a storage medium that can be read by a computer, and may be installed from the storage medium in the storage unit 19 of the control device 4. Examples of storage media that can be read by a computer include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnet 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 mounted on the carrier mounting portion 11, and receives the taken out wafer W. Placed on Watanabe 14. The wafer W placed on the delivery section 14 is taken out from the delivery section 14 by the substrate transfer device 17 of the processing station 3 and carried into the processing unit 16.

The wafer W carried into the processing unit 16 is processed by the processing unit 16, then carried out 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 section 14 is returned to the carrier C of the carrier mounting section 11 by the substrate transfer device 13.

Next, the configuration of the processing unit 16 will be described with reference to FIG. The processing unit 16 has a chamber (unit casing) 20. An FFU (Fan Filter Unit) 21 is provided on the ceiling of the chamber 20. The FFU 21 forms a downflow of clean gas, eg, clean air, in the chamber 20.

A substrate holding rotating portion 30 called a spin chuck or the like is provided in the chamber 20. The substrate holding rotating portion 30 has a chuck 31 (board holding portion) and a rotating motor 32 (rotation driving unit) for rotating the chuck 31, and holds the wafer W, which is the substrate to be processed, in a horizontal posture. , Can be rotated around the vertical axis. The chuck 31 may be a vacuum chuck that attracts the lower surface of the wafer W, or may be a mechanical chuck that holds the peripheral edge portion of the wafer W by a plurality of gripping claws. The substrate holding rotating portion 30 is provided with an elevating mechanism (not shown), and the chuck 31 can be elevated by this elevating mechanism.

A first nozzle arm 41 is provided in the chamber 20. The nozzle holder 42 at the tip of the first nozzle arm 41 has a chemical solution nozzle 43A for discharging DHF (dilute hydrofluoric acid) as a chemical solution, a rinse nozzle 43B for discharging DIW (pure water) as a rinse solution, and drying. A drying liquid nozzle 43C that discharges IPA as a liquid is supported. The base end portion of the first nozzle arm 41 is attached to the first arm drive mechanism 45. The first arm drive mechanism 45 can raise and lower the first nozzle arm 41 in the vertical direction and can rotate around the vertical axis 46. The chemical solution nozzle 43A, the rinse nozzle 43B, and the drying solution nozzle 43C can move above the wafer W between a position directly above the center of the wafer W and a position directly above the peripheral edge of the wafer W. .. The “center portion of the wafer W” includes not only the exact center of rotation WC of the wafer W but also a region in the vicinity thereof. The "peripheral portion of the wafer W" includes not only the outer peripheral edge of the wafer W but also a region in the vicinity thereof. The above three nozzles 43A, 43B, and 43C can also be retracted to a retracted position (a position outside the liquid receiving cup described later) that is displaced from above the wafer W.

A second nozzle arm 51 is further provided in the chamber 20. The nozzle holder 52 at the tip of the second nozzle arm 51 is supported by a gas nozzle 53 that discharges nitrogen gas (N2 gas) as a dry gas and a UV lamp 54 that irradiates ultraviolet rays. The base end portion of the second nozzle arm 51 is attached to the second arm drive mechanism 55. The second arm drive mechanism 55 can raise and lower the second nozzle arm 51 in the vertical direction, and can rotate the second nozzle arm 51 around the vertical axis 56. The gas nozzle 53 and the UV lamp 54 can move above the wafer W between a position directly above the center of the wafer W and a position directly above the peripheral edge of the wafer W. Further, the gas nozzle 53 and the UV lamp 54 can be retracted to a retracted position (a position outside the liquid receiving cup, which will be described later), which is deviated from above the wafer W.

The planar positional relationship between the wafer W held by the substrate holding rotating portion 30 and the first nozzle arm 41 and the second nozzle arm 51 can be as shown in FIGS. 3A and 3B, for example. However, it is not limited to this. In FIG. 3A, the first nozzle arm 41 and the second nozzle arm 51 are arranged at point-symmetrical positions with the rotation center WC of the wafer W as the center of symmetry. In FIG. 3B, the first nozzle arm 41 and the second nozzle arm 51 are arranged in parallel (side by side). The first nozzle arm 41 and the second nozzle arm 51 rotate as shown by arrows 47 and 57.

A chemical solution supply mechanism 71 is connected to the chemical solution nozzle 43A. A rinse liquid supply mechanism 72 is connected to the rinse nozzle 43B. The drying liquid supply mechanism 73 is connected to the drying liquid nozzle 43C. A gas supply mechanism 74 is connected to the gas nozzle 53. In each supply mechanism (71, 72, 73, 74), the elements indicated by double circles in FIG. 3 are the supply sources (for example, factory power, tank, etc.) of each processing fluid (chemical solution, rinsing solution, drying solution, gas). (Cylinder, etc.), and the element schematically indicated by the white square with "X" in FIG. 3 is the flow control device. The flow control device includes, for example, an on-off valve, a flow meter, a flow control valve, and the like.

Depending on the type of chemical solution, the chemical solution and the rinse solution can be supplied from the same nozzle. For example, there is no particular problem even if DHF as a chemical solution and DIW as a rinsing solution are mixed, so that they can be supplied from the same nozzle. In this case, the chemical solution supply mechanism 71 and the rinse solution supply mechanism 72 are connected to the same nozzle.

The UV lamp 54 comprises, for example, an LED lamp and generates, for example, 172 nm ultraviolet light. A power feeding device 75 is connected to the UV lamp 54.

As shown in FIG. 4A, the gas nozzle 53 and the UV lamp 54 may be integrated. In the configuration example of FIG. 4, two semicircular slit-shaped gas discharge ports 53a surrounding the light emitting surface 54a of the UV lamp 54 are provided. One gas discharge port 53a is on the front side in the traveling direction (see arrow MV) when the gas nozzle 53 moves with the rotation of the second nozzle arm 51, and the other gas discharge port 53a is on the rear side in the traveling direction.

As shown in FIG. 4B, a plurality (many) gas discharge ports 53b arranged in the circumferential direction may surround the light emitting surface 54a of the UV lamp 54. As shown in FIG. 4C, a slit-shaped gas discharge port 53a extending linearly around the light emitting surface 54a of the UV lamp 54 may be provided. In the example of FIG. 4C, one gas discharge port 53c is on the front side in the traveling direction (see arrow MV) when the gas nozzle 53 moves with the rotation of the second nozzle arm 51, and the other gas discharge port 53c advances. It is on the rear side of the direction.

As shown in FIGS. 4A to 4C, the width DN of the arrangement area of the gas nozzle 53 measured in the direction orthogonal to the traveling direction MV when the gas nozzle 53 moves with the rotation of the second nozzle arm 51 is the width DN of the UV lamp 54. It is preferably larger than the width DL of the light emitting surface 54a. In the drying step described later, the width DN of the arrangement region of the gas nozzle 53 in front of the traveling direction when the gas nozzle 53 moves toward the peripheral edge of the wafer is made larger than the width DL of the light emitting surface of the UV lamp 54. , The undried dry solution (IPA) is reliably pushed away. Therefore, it is possible to irradiate the surface of the wafer W in a dry state with ultraviolet rays. In addition to this, by making the width DN of the arrangement region of the gas nozzle 53 rearward in the traveling direction larger than the width DL of the light emitting surface 54a of the UV lamp 54, the optical path of ultraviolet rays from the UV lamp 54 toward the surface of the wafer W becomes. It becomes substantially surrounded by the inert gas. As a result, the oxygen concentration in the optical path of ultraviolet rays can be lowered, and the generation of ozone can be suppressed. This effect is greater in the examples of FIGS. 4A and 4B, where the ultraviolet path is largely surrounded by the inert gas.

As shown in FIG. 2, a liquid receiving cup 60 is provided in the chamber 20 so as to surround the chuck 31 of the substrate holding rotating portion 30. The liquid receiving cup 60 collects the processing liquid scattered from the rotating wafer W.

A drainage port 61 and an exhaust port 62 are provided at the bottom of the liquid receiving cup 60. The processing liquid captured by the liquid receiving cup 60 flows to the outside of the processing unit 16 through the drainage port 61, is collected and reused, or is discarded in the factory drainage system. The atmosphere of the internal space of the liquid receiving cup 60 is discharged to the factory exhaust system having a decompressed atmosphere through the exhaust port 62 and the exhaust pipeline 63. The exhaust pipeline 63 may be provided with an ejector (not shown) for promoting exhaust and a valve (for example, a butterfly valve) for controlling the exhaust flow rate.

In FIG. 2, the internal structure of the liquid receiving cup 60 is shown in a significantly simplified manner. The liquid receiving cup 60 flows through the liquid receiving cup 60 through different routes through which different types of treatment liquids (for example, acidic chemicals, alkaline chemicals, organic chemicals) can be switched, and a plurality of different exhaust ports 62 and a plurality of exhausts are exhausted. It may be configured to be discharged to the outside of the processing unit 16 via the pipeline 63. Such a configuration is well known in the technical field of semiconductor manufacturing equipment, and the description thereof will be omitted.

The rinse nozzle 43B, the rinse liquid supply mechanism 72, the first nozzle arm 41 to which the rinse nozzle 43B is attached, and the first arm drive mechanism 45 supply the rinse liquid to a desired position on the surface of the wafer W at a desired flow rate. A rinse liquid supply unit that can be used is configured. The first nozzle arm 41 and the first arm drive mechanism 45 to which the drying liquid nozzle 43C, the drying liquid supply mechanism 73, and the drying liquid nozzle 43C are attached supply the drying liquid to a desired position on the surface of the wafer W at a desired flow rate. A dry liquid supply unit that can be used is configured. A gas supply capable of spraying dry gas at a desired position on the surface of the wafer W at a desired flow rate by the second nozzle arm 51 and the second arm drive mechanism 55 to which the gas nozzle 53, the gas supply mechanism 74, and the gas nozzle 53 are attached. The part is composed. Ultraviolet rays capable of irradiating a desired position on the surface of the wafer W with ultraviolet rays of a desired intensity by the second nozzle arm 51 and the second arm drive mechanism 55 to which the UV lamp 54, the power feeding device 75, and the UV lamp 54 are attached. The irradiation unit is configured.

Next, a series of liquid treatment steps performed on one wafer W by the substrate processing system 1 will be described. In the operation of the board processing system 1 described below, the control device 4 operates various components of the board processing system 1 (board holding rotating unit 30, first and second arm drive mechanisms 45, 55, flow control device, etc.). It is realized by controlling.

The arm of the substrate transfer device 17 holding the unprocessed wafer W enters the processing unit 16. At this time, the first and second nozzle arms 41 and 51 are in retracted positions away from above the liquid receiving cup 60. The arm of the substrate transfer device 17 passes the wafer W to the chuck 31 and exits from the processing unit 16.

Next, the substrate holding rotating portion 30 rotates the wafer W. The rotation of the wafer W continues until a series of processes for the wafer W are completed.

[Chemical solution treatment process]
First, the chemical solution nozzle 43A held at the tip of the first nozzle arm 41 is located directly above the central portion of the rotating wafer W, and the chemical solution (DHF in this example) is discharged toward the surface of the wafer W. The DHF that has landed on the central portion of the wafer W flows while spreading toward the peripheral portion of the wafer W due to centrifugal force, and the entire surface of the wafer W is covered with the liquid film of the DHF. The DHF is supplied to the surface of the wafer W for a predetermined time, whereby the surface of the wafer W is treated with a chemical solution (etching, cleaning, etc.).

[Rinse process]
Next, the discharge of DHF from the chemical solution nozzle 43A is stopped, the rinse nozzle 43B is located directly above the center of the rotating wafer W, and the rinse solution (DIW in this example) is directed toward the surface of the wafer W. Discharge. The discharge of DHF from the chemical solution nozzle 43A may be stopped after the discharge of DIW from the rinse nozzle 43B is started. The DIW that has landed on the central portion of the wafer W flows while spreading toward the peripheral portion of the wafer W due to centrifugal force, and the entire surface of the wafer W is covered with the liquid film of the DIW. The DIW is supplied to the surface of the wafer W for a predetermined time, whereby the DHF remaining on the surface of the wafer W, the reaction product produced in the chemical solution treatment step, and the like are washed away by the DIW.

[Dry solution replacement process]
The drying liquid replacement step will be described with reference to FIGS. 5 and 6. When the rinsing step is executed for a predetermined time, the discharge of DIW from the rinsing nozzle 43B is stopped, and the drying liquid nozzle 43C is located directly above the center of the rotating wafer W, and the drying liquid, in this example, is located. The IPA is discharged toward the surface of the wafer W. It is preferable to stop the discharge of DIW from the rinse nozzle 43B after the start of discharge of IPA from the drying liquid nozzle 43C. In other words, it is preferable that the end of the DIW discharge period from the rinse nozzle 43B and the start of the IPA discharge period from the drying solution nozzle 43C overlap to some extent in time. The IPA that has landed on the center of the wafer W flows while spreading toward the peripheral edge of the wafer W due to centrifugal force, whereby the DIW remaining on the surface of the wafer W is replaced by the IPA, and the entire surface of the wafer W is replaced. (Including the surface of the concave portion of the pattern) is covered with IPA (see FIG. 5 (A)).

[Drying process]
As shown in FIG. 5A, slightly before the end of the drying liquid replacement step, the gas nozzle 53 and the UV lamp 54 provided at the tip of the second nozzle arm 51 are set to be true near the center of the wafer W. It is moved to the upper position, that is, a position close to the drying liquid nozzle 43C. When the drying liquid replacement step is completed (that is, when the replacement from DIW to IPA is completed), the drying liquid nozzle 43C is positioned directly above the peripheral edge of the wafer W while continuing to discharge IPA from the drying liquid nozzle 43C. I will move it toward. As a result, the position of the liquid landing point PI on the surface of the wafer W of the IPA (that is, the supply position of the IPA on the surface of the wafer W) moves from the central portion of the wafer W toward the peripheral portion. Since no new IPA is supplied to the region (inner in the radial direction) closer to the rotation center WC of the wafer W than the liquidation point PI of the IPA on the surface of the wafer W, the region becomes dry. That is, an annular dry region AD is formed in the central portion of the wafer W. The annular region (radially outward) farther from the center of rotation of the wafer W than the liquidation point PI remains wet by the IPA. As the rinse nozzle 43B moves, the diameter of the circular dry region expands.

The gas nozzle 53 and the UV lamp 54 are positioned directly above the center of the wafer W in accordance with the movement of the drying liquid nozzle 43C from the position directly above the center of the wafer W (FIG. 5 (A) → FIG. 5 (FIG. 5). B)). Then, the discharge of N ₂ gas from the gas nozzle 53 and the irradiation of ultraviolet rays from the UV lamp 54 are started. The discharge of N ₂ gas from the gas nozzle 53 may be started shortly before the gas nozzle 53 is located directly above the center of the wafer W. By doing so, the central portion of the wafer W in a sufficiently dried state can be irradiated with ultraviolet rays.

Incidentally, (see also FIG. 6) below, for simplification of explanation, the irradiation position of the UV on the surface of the wafer W and PU, and position PG1, PG2 blowing N ₂ gas from the gas nozzle 53. Incidentally, blowing position of N ₂ gas from the gas nozzle 53, when viewed from the horizontal direction orthogonal to the traveling direction of the gas nozzle 53, the nozzle forward traveling direction of the blowing position PG1 than the irradiation position PU, the nozzle progression than the irradiation position PU The spraying position behind the direction is called PG2.

Next, the gas nozzle 53 and the UV lamp 54 are moved toward a position directly above the peripheral edge of the wafer W while continuing the discharge of the dry gas from the gas nozzle 53 and the irradiation of ultraviolet rays from the UV lamp 54. (FIG. 5 (C)). At this time, the distance from the rotation center WC of the wafer W to the UV irradiation position PU and _{N 2} gas blowing position PG1, PG2, while maintaining less than the distance from the rotation center WC of the wafer W to IPA Chakuekiten PI, The drying liquid nozzle 43C, the gas nozzle 53 and the UV lamp 54 are moved. By doing so, the surface of the wafer W immediately after the IPA is sufficiently dried is irradiated with ultraviolet rays.

At this time, the moving direction of the gas nozzle 53 and the UV lamp 54 is preferably a moving direction away from the drying liquid nozzle 43C, in other words, a direction substantially opposite to the moving direction of the drying liquid nozzle 43C. That is, for example, in the arrangement shown in FIGS. 3A and 3B, it is preferable that the gas nozzle 53, the UV lamp 54, and the drying liquid nozzle 43C both move away from the rotation center WC of the wafer W. By doing so, it is possible to prevent the splash of IPA (fine droplets generated when the IPA collides with the surface of the wafer W) from adhering to the gas nozzle 53 and the UV lamp 54. However, the gas nozzle 53 and the UV lamp 54 may be moved in the same direction as or substantially in the same direction as the drying liquid nozzle 43C.

When the IPA landing point PI reaches the peripheral edge of the wafer W, the discharge of IPA from the drying liquid nozzle 43C is stopped. Thereafter When the amount of UV that has been predetermined on the periphery by UV lamps 54 that has reached the upper peripheral portion of the wafer W is irradiated, the irradiation is stopped ultraviolet from N ₂ gas discharge and UV lamp 54 from the gas nozzle 53 Will be done. With the above, the drying step is completed.

As described above, a series of processes for one wafer W is completed. The processed wafer W is carried out from the processing unit 16 in the reverse procedure of the loading.

According to the above embodiment, the following advantageous effects can be obtained.

(1) Since the surface of the wafer W immediately after the IPA has evaporated is irradiated with ultraviolet rays, the generation of particles derived from high molecular weight organic impurities contained in the IPA can be significantly suppressed. When drying is performed using ordinary IPA, an increase in the amount of particles is observed with the passage of time from the end of drying. According to the research of the inventor, it was confirmed that IPA containing an increased amount of particles contained a relatively large amount of high molecular weight organic impurities (CxHy, C16 or more). It is considered that the polymer organic impurities remain on the surface of the wafer W after the evaporation of the IPA and are precipitated as particles by reacting with the moisture around the wafer W. According to the above embodiment, by irradiating the surface of the wafer W immediately after the IPA has evaporated with ultraviolet rays, the CC bonds of the high molecular weight organic impurities are broken and the molecular weight is reduced, so that the wafers do not precipitate as particles. Alternatively, it is considered that it becomes difficult to precipitate.

(2) Since an inert gas such as N ₂ gas is supplied around the UV lamp 54, the oxygen concentration around the UV lamp 54 is significantly reduced. Therefore, it is possible to prevent the generation of ozone that may be generated by irradiating oxygen with ultraviolet rays, and to prevent the surface of the wafer W (for example, the metal wiring layer exposed on the surface of the wafer W) from being oxidized by ozone. Can be done. Further, since the inert gas such as N ₂ gas is a low humidity gas containing almost no water, the humidity of the atmosphere near the boundary between the dry region and the non-dry region also decreases. For this reason, residual polymer organic impurities (those in which the CC bond is not divided) are less likely to precipitate as particles. Also, by the gas nozzle 53 while spraying from the gas nozzle 53 N ₂ gas on the surface of the wafer W moves toward the peripheral portion of the wafer W, IPA liquid film is extruded toward the peripheral portion of the wafer W, thereby the wafer It is possible to accelerate the drying of the surface of W.

The effect of (1) above, which is derived from the disruption of the CC bond of the polymer organic impurity, decreases as time passes after the evaporation of IPA. Therefore, for example, if the ultraviolet irradiation step is performed as a separate step after the completion of the drying step, the effect of suppressing particle precipitation is significantly reduced as compared with the above embodiment. Further, when an ultraviolet lamp capable of irradiating the entire surface of the wafer W at the same time is arranged above the wafer W in the chamber 20, it becomes difficult to suppress ozone generation in the above (2). In order to sufficiently suppress ozone generation, for example, it is necessary to create a high-concentration N ₂ gas atmosphere in the chamber 20, and the running cost of the substrate processing system 1 increases due to the consumption of a large amount of N ₂ gas.

In the above embodiment, the UV lamp 54 and the gas nozzle 53 are integrated, but the present invention is not limited to this, and the UV lamp 54 and the gas nozzle 53 may be separate parts.

Go after the above drying process is completed, again, while irradiating with UV by a UV lamp 54 while discharging the N ₂ gas from the gas nozzle 53, toward the gas nozzle 53 and the UV lamp 54 from the center of the wafer W to the peripheral portion You may perform the process of causing. As a result, the generation of particles derived from the drying liquid can be further suppressed.

It is preferable to supply the inert gas through the gas nozzle 53, but if the generation of ozone does not matter, the inert gas may not be supplied. Even when the effect of pushing out the IPA by the inert gas is not desired, the inert gas may not be supplied from the gas nozzle 53. That is, if only the particle suppressing effect among the effects of the above embodiment is desired, the surface of the wafer may be irradiated with ultraviolet rays immediately after the IPA (drying liquid) is dried.

The test results confirmed for the effects of the above embodiments will be briefly described. The lower part of the table of FIG. 7 is a schematic diagram (rough copy of the analyzer image) showing the distribution of particles having a size larger than 35 nm existing on the wafer W when the treatment is performed based on the above embodiment. As a comparative example, the upper part of the table of FIG. 7 shows a case where the procedure is performed under the same conditions as in the embodiment except that there is no ultraviolet irradiation. It can be seen that the particles are significantly reduced both immediately after the treatment and after being left for a certain period of time after the treatment. In addition, "ADDER" indicates the difference immediately after the treatment and after being left for a certain period of time after the treatment. The numerical values shown in each frame of the table indicate the number of particles having a size of 35 nm or more.

As can be seen from the above test results, the increase in particles from immediately after the treatment to after being left for a certain period of time after the treatment is larger in the central portion of the wafer W than in the peripheral portion. Therefore, it is preferable to either lengthen the ultraviolet irradiation time in the central portion of the wafer W peripheral portion and / or increase the ultraviolet intensity in the central portion of the wafer W peripheral portion. The ultraviolet irradiation time can be lengthened, for example, by lowering the moving speed of the UV lamp 54 from the center of the wafer W to the peripheral edge of the wafer W at the center of the wafer W.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The above embodiments may be omitted, replaced, or modified in various forms without departing from the scope of the appended claims and their gist.

W Substrate 4 Control unit 31 Substrate holding unit 32 Rotation drive unit 43B, 72, 41, 45 Rinse liquid supply unit 43C, 73, 41, 45 Dry liquid supply unit 54, 75, 51, 55 Ultraviolet irradiation unit

Claims (11)

The board holding part that holds the board and
A rotary drive unit that rotationally drives the substrate holding unit,
A rinse liquid supply unit that supplies the rinse liquid to the substrate held by the substrate holding unit, and a rinse liquid supply unit.
A drying liquid supply unit that supplies the drying liquid to the substrate held by the substrate holding unit, and a drying liquid supply unit.
An ultraviolet irradiation unit that irradiates the substrate held by the substrate holding unit with ultraviolet rays,
The rotation drive unit, the rinse liquid supply unit, the drying liquid supply unit, and a control unit for controlling the ultraviolet irradiation unit are provided.
The control unit supplies the rinse liquid to the rotating substrate held by the substrate holding unit by the rinse liquid supply unit, supplies the drying liquid to the central portion of the substrate by the drying liquid supply unit, and then supplies the drying liquid to the central portion of the substrate. By moving the landing position of the drying liquid from the central portion to the peripheral portion of the substrate, the dry region formed on the substrate is expanded from the central portion to the peripheral portion, and the ultraviolet irradiation portion applies ultraviolet rays to the dry region. At this time, the ultraviolet irradiation position is maintained from the center of the substrate while maintaining the distance from the center of rotation of the substrate to the landing position of the drying liquid larger than the distance from the center of rotation of the substrate to the irradiation position of ultraviolet rays. A substrate processing device that moves to the periphery. Further provided with an inert gas supply unit that supplies the inert gas to the substrate held by the substrate holding unit is provided.
The control unit is at least closer to the center of rotation of the substrate than the irradiation position of the ultraviolet rays when the ultraviolet irradiation unit irradiates the substrate with the ultraviolet rays while moving the irradiation position of the ultraviolet rays from the central portion to the peripheral portion of the substrate. While maintaining the state in which the inert gas is sprayed on the substrate portion, the inert gas is sprayed by the inert gas supply portion while moving the spraying position of the inert gas from the central portion to the peripheral portion of the substrate. The substrate processing apparatus according to claim 1. Further provided with an inert gas supply unit that supplies the inert gas to the substrate held by the substrate holding unit is provided.
When the control unit irradiates the substrate with ultraviolet rays while moving the irradiation position of the ultraviolet rays from the central portion to the peripheral portion of the substrate, the control unit is at least closer to the center of rotation of the substrate than the supply position of the drying liquid. While maintaining the state in which the inert gas is sprayed on the portion of the substrate that is close and farther from the center of rotation of the substrate than the irradiation position of ultraviolet rays, the position where the inert gas is sprayed is moved from the central portion to the peripheral portion of the substrate. The substrate processing apparatus according to claim 1 or 2, wherein the inert gas is blown by the inert gas supply unit. The substrate processing apparatus according to claim 1, wherein the wavelength of the ultraviolet rays emitted by the ultraviolet irradiation unit is 172 nm. The substrate processing apparatus according to claim 3, wherein the ultraviolet irradiation unit includes a UV lamp, and the inert gas supply unit includes an inert gas nozzle that surrounds the UV lamp. The substrate processing apparatus according to claim 5, wherein the UV lamp and the inert gas nozzle are integrated. The substrate processing apparatus according to claim 5, wherein the width of the arrangement region of the inert gas nozzle measured in a direction orthogonal to the moving direction of the UV lamp is larger than the width of the light emitting surface of the UV lamp. The ultraviolet irradiation unit includes a UV lamp, the inert gas supply unit has a first inert gas nozzle and a second inert gas nozzle, and the first inert gas nozzle and the second inert gas nozzle are at the center of the substrate. The substrate processing apparatus according to claim 3, which is provided at least in front of and behind the UV lamp when viewed in the moving direction of the UV lamp from the portion to the peripheral portion. Rotating the board in a horizontal position around the vertical axis,
Supplying the rinse liquid to the substrate and
By supplying a drying liquid to the substrate and replacing the rinsing liquid on the substrate with the drying liquid,
By moving the liquid landing position of the drying liquid on the substrate from the central portion of the substrate to the peripheral portion, and expanding the drying region of the substrate from the central portion to the peripheral portion.
When the liquid landing position of the drying liquid on the substrate is moved from the central portion to the peripheral portion of the substrate, the distance from the rotation center of the substrate to the liquid landing position of the drying liquid is the distance of the substrate. Irradiating the substrate with the ultraviolet rays while moving the irradiation position of the ultraviolet rays from the center portion to the peripheral portion of the substrate while maintaining the distance from the center of rotation to the irradiation position of the ultraviolet rays.
Substrate processing method including. When the substrate is irradiated with the ultraviolet rays while moving the irradiation position of the ultraviolet rays from the central portion to the peripheral portion of the substrate, the substrate is further provided with an inert gas, and the inert gas is supplied. This means that the inert gas is sprayed from the center to the periphery of the substrate while maintaining the state in which the inert gas is sprayed on the portion of the substrate that is closer to the rotation center of the substrate than the irradiation position of the ultraviolet rays. The substrate processing method according to claim 9, which is executed while being moved to a unit. When the substrate is irradiated with the ultraviolet rays while moving the irradiation position of the ultraviolet rays from the central portion to the peripheral portion of the substrate, the substrate is further provided with an inert gas, and the inert gas is supplied. In order to maintain the state in which the inert gas is sprayed on the portion of the substrate farther from the center of rotation of the substrate than at least the irradiation position of the ultraviolet rays, the position where the inert gas is sprayed is set from the center to the periphery of the substrate. The substrate processing method according to claim 9, which is executed while being moved to a unit.

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