JP2005268287A - Substrate processing process, equipment and system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent oxidation of a substrate due to dissolved oxygen in rinse liquid by suppressing increase in concentration of dissolved oxygen in rinse liquid after discharging rinse liquid from a nozzle toward the substrate, and to suppress adhesion of contaminant to the substrate. <P>SOLUTION: On the substrate processing system 100 side, pure water supplied from a pure water supply source 200 to a substrate processing system 100 contains nitrogen supersaturated by nitrogen dissolution units 58 and 78, thus producing rinse liquid containing nitrogen over solubility limit. Nitrogen is then degassed from rinse liquid thus produced by means of degassing units 59 and 79 such that nitrogen contained in the rinse liquid becomes below solubility limit thus producing degassed rinse liquid. The degassed rinse liquid is discharged from nozzles 6 and 25 and supplied to a substrate W which is thereby rinsed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention provides a rinsing process by supplying a rinsing liquid to various substrates (hereinafter simply referred to as “substrates”) such as semiconductor wafers, glass substrates for photomasks, glass substrates for liquid crystal displays, glass substrates for plasma displays, and substrates for optical disks. The present invention relates to a substrate processing method, a substrate processing apparatus, and a substrate processing system.

  The manufacturing process of an electronic component such as a semiconductor device or a liquid crystal display device includes a step of repeatedly forming a fine pattern by repeatedly performing processes such as film formation and etching on the surface of the substrate. Here, in order to perform fine processing satisfactorily, it is necessary to keep the substrate surface clean, and the substrate is subjected to a cleaning process as necessary (see Patent Document 1). In the invention described in Patent Document 1, after cleaning the substrate surface with a processing liquid suitable for cleaning processing, that is, the cleaning liquid, the processing liquid remaining on the substrate surface is rinsed and removed using pure water as a rinsing liquid. Yes. Further, after the rinsing process is completed, the rinsing liquid remaining on the substrate surface is shaken off and dried by rotating the substrate at a high speed.

Japanese Patent Laid-Open No. 5-29292 (paragraphs [0013] to [0015])

  However, when pure water is used as the rinsing liquid, the dissolved oxygen contained in the pure water oxidizes all or part of the substrate surface cleaned with the cleaning liquid, and an oxide film is formed on the substrate surface. There was a problem. Therefore, in order to solve this problem, a measure has been taken to reduce the dissolved oxygen concentration of pure water used as the rinse liquid.

  However, in the actual rinsing process, since the rinsing liquid is discharged from the rinsing nozzle toward the substrate surface, the rinsing liquid is exposed to the air as soon as it is discharged from the nozzle. For this reason, even if the dissolved oxygen concentration in the rinse liquid is lowered in advance, oxygen in the air dissolves in the rinse liquid immediately after discharge from the nozzle, and the dissolved oxygen concentration in the rinse liquid rapidly increases. Further, the penetration of oxygen present in the air into the rinsing liquid in this way continues not only immediately after discharge from the nozzle, but also continues at a predetermined rising speed thereafter. Therefore, it is important to reduce the amount of oxygen dissolved in the rinse liquid after being discharged from the nozzle. That is, reducing the dissolved oxygen concentration in the rinsing liquid during the period from the start of the rinsing process to the end of the drying process (for example, about 30 seconds) is accompanied with the rinsing process while the substrate surface is wet with the rinsing liquid. This is very important in preventing oxidation of the substrate surface. However, no effective countermeasures have been conventionally taken in this regard, leaving much room for improvement.

  In order to perform fine processing on the substrate satisfactorily, it is necessary not only to prevent oxidation of the substrate surface but also to prevent contaminants such as particles, metal impurities, and chemical impurities from adhering to the substrate surface. . This is because if these particles adhere to the substrate surface, it causes various defects such as pattern defects. Therefore, it is necessary to take into consideration not only the oxidation of the substrate surface but also the adhesion of particles and the like to the substrate surface, and take preventive measures.

  The present invention has been made in view of the above problems, and suppresses an increase in the dissolved oxygen concentration in the rinsing liquid after discharging the rinsing liquid from the nozzle toward the substrate, whereby the substrate due to the dissolved oxygen in the rinsing liquid. An object of the present invention is to provide a substrate processing method, a substrate processing apparatus, and a substrate processing system capable of preventing the oxidation of the substrate and suppressing the adhesion of contaminants to the substrate.

  In order to achieve the above object, a substrate processing method according to the present invention includes a wet processing step of supplying a processing liquid to a substrate to perform a predetermined wet processing, and adding nitrogen to pure water in a supersaturated manner. A rinsing liquid generating step for generating a rinsing liquid that exceeds the solubility limit, and a degassed rinsing liquid by degassing part of the nitrogen from the rinsing liquid so that the nitrogen contained in the rinsing liquid is below the solubility limit. A deaeration process to be generated, and a rinsing process of supplying a degassed rinse liquid to the substrate after the wet process process to subject the substrate to a rinse process using the degassed rinse liquid.

  According to such a structure, the process liquid adhering to the substrate surface is washed away by performing the rinse process with respect to the board | substrate with which the wet process by the process liquid was performed. Here, since the rinsing liquid (degassed rinsing liquid) used in the rinsing process is generated as follows, the generation of an oxide film on the substrate due to dissolved oxygen in the rinsing liquid is suppressed, and the substrate is supplied to the substrate. The adhesion of contaminants such as particles can be prevented. That is, in the rinse liquid generating step, a rinse liquid containing nitrogen exceeding the solubility limit is generated by adding nitrogen in a supersaturated state in pure water in advance. Thus, in the rinse liquid formed by adding nitrogen to pure water, the dissolved oxygen concentration is lowered by the addition of nitrogen. Moreover, pure water having a low dissolved oxygen concentration can be easily obtained by adding nitrogen to the pure water in a supersaturated manner. On the other hand, when nitrogen is added to supersaturation, a part of nitrogen contained in the rinse liquid becomes bubbles, and the rinsing process is performed with the rinse liquid containing the bubbles. Therefore, a problem that particles or the like adhere to the substrate surface may occur.

  Therefore, in the deaeration process following the rinse liquid generation process, a part of the nitrogen is degassed from the rinse liquid so that the nitrogen contained in the rinse liquid is below the solubility limit, thereby generating a degassed rinse liquid. The As a result, it is possible to prevent the nitrogen contained in the rinse liquid from forming bubbles and attaching particles or the like to the substrate surface.

  When this degassed rinsing liquid is supplied toward the substrate, the rinsing liquid is thereafter exposed to the air, leading to an increase in the dissolved oxygen concentration, but the rate of increase is suppressed by the addition of nitrogen. Therefore, by using such a rinsing liquid (degassed rinsing liquid), the dissolved oxygen concentration in the rinsing liquid rapidly increases during the period from when the rinsing liquid is discharged toward the substrate until it is removed from the substrate. The generation of an oxide film on the substrate due to dissolved oxygen in the rinse liquid can be prevented. In addition, since the nitrogen contained in the rinse liquid is deaerated so as to be below the solubility limit, the nitrogen in the rinse liquid becomes bubbles to prevent particles and the like from adhering to the substrate surface.

  Here, the rinsing step may be performed in an inert gas atmosphere. By doing so, the oxygen concentration in the rinse liquid (degassed rinse liquid) and the ambient atmosphere of the substrate is lowered. Therefore, oxygen itself that can be dissolved in the rinsing liquid is reduced, and it is possible to further suppress an increase in the dissolved oxygen concentration of the rinsing liquid during a period from when the rinsing liquid is discharged toward the substrate until it is removed from the substrate. it can.

  In order to achieve the above-described object, the substrate processing apparatus of the present invention includes a rinsing liquid generating means for adding nitrogen to pure water to generate a nitrogen-rich rinsing liquid, and a rinse generated by the rinsing liquid generating means. Degassing means for generating a degassed rinse liquid by degassing a part of nitrogen from the liquid, and supplying the degassed rinse liquid to the substrate by discharging the degassed rinse liquid from the nozzle toward the substrate And rinsing means for rinsing the substrate.

  According to such a structure, the dissolved oxygen concentration of a rinse liquid is reduced by the rinse liquid production | generation means producing | generating the rinse liquid in which nitrogen was abundantly added to the pure water. Then, a part of nitrogen is degassed from the generated rinse liquid by the degassing means, so that the rinse liquid is dissolved at a low dissolved oxygen concentration and does not form nitrogen bubbles (degassed rinse liquid). Will be generated. Then, this degassed rinse liquid is discharged toward the substrate, whereby the substrate is rinsed. At this time, the degassed rinse liquid is exposed to the air atmosphere, but as described above, the rate of increase in the dissolved oxygen concentration is suppressed by the addition of nitrogen. Therefore, the dissolved oxygen concentration of the rinsing liquid does not increase rapidly during the period from when the rinsing liquid is discharged from the nozzle toward the substrate until it is removed from the substrate. Generation of an oxide film can be prevented. In addition, since a part of nitrogen is degassed from the rinsing liquid, the nitrogen contained in the rinsing liquid becomes bubbles to prevent particles and the like from adhering to the substrate surface.

  In addition, an atmosphere blocking unit that is spaced from the substrate while facing the substrate to which the degassed rinse liquid is supplied, and an inert gas that supplies an inert gas to a space formed between the atmosphere blocking unit and the substrate You may make it further provide a supply means.

  By adopting such a configuration, the rinsing liquid (degassed rinsing liquid) and the atmosphere around the substrate are filled with an inert gas such as nitrogen, so that oxygen that can be dissolved in the rinsing liquid is reduced. be able to. As a result, it is possible to further suppress an increase in the dissolved oxygen concentration of the rinsing liquid during a period from when the rinsing liquid is discharged from the nozzle toward the substrate until it is removed from the substrate.

  Further, in order to achieve the above-described object, the substrate processing system of the present invention is provided separately from a pure water supply unit that supplies pure water and a pure water supply unit, and receives pure water supplied from the pure water supply unit. The substrate processing system includes a substrate processing unit that performs a rinsing process on the substrate, and the substrate processing unit generates nitrogen-rich rinse liquid by adding nitrogen to pure water supplied from the pure water supply unit. A rinsing liquid generating means, a degassing means for degassing a part of nitrogen from the rinsing liquid generated by the rinsing liquid generating means, and generating a degassed rinsing liquid; A rinsing means for supplying a degassed rinsing liquid to the substrate by discharging toward the substrate and rinsing the substrate is provided in the same unit body.

  In the substrate processing system configured as described above, pure water is supplied to the substrate processing unit from a pure water supply unit provided separately from the substrate processing unit, and the substrate is rinsed. As described above, even when pure water is supplied from a separately provided pure water supply unit, nitrogen is added to the pure water in the substrate processing unit to generate a nitrogen-rich rinse liquid. By degassing a part of nitrogen from the rinsing liquid, the substrate is supplied with a rinsing liquid (degassed rinsing liquid) that has a low dissolved oxygen concentration and is dissolved to the extent that nitrogen does not form bubbles. As a result, as described above, oxidation to the substrate by dissolved oxygen in the rinse liquid is prevented, and adhesion of particles and the like to the substrate surface is suppressed.

  The substrate processing unit also includes an atmosphere blocking unit that is spaced from the substrate while facing the substrate to which the rinsing liquid is supplied, and an inert gas that is supplied to the space formed between the atmosphere blocking unit and the substrate. An active gas supply means may be further provided in the unit main body.

  By adopting such a configuration, as described above, the rinse liquid (degassed rinse liquid) and the ambient atmosphere of the substrate are filled with an inert gas such as nitrogen, so that the rinse liquid is directed from the nozzle toward the substrate. Thus, it is possible to further suppress an increase in the dissolved oxygen concentration of the rinse liquid during the period from the discharge to the removal from the substrate.

  According to the present invention, a nitrogen-rich rinse liquid is generated by adding abundant nitrogen to pure water, and part of the nitrogen is degassed from the generated rinse liquid. For this reason, the substrate is rinsed with a rinsing liquid (degassed rinsing liquid) dissolved to such an extent that nitrogen does not form bubbles while having a low dissolved oxygen concentration. As a result, the dissolved oxygen concentration in the rinsing liquid does not rise rapidly during the period from when the rinsing liquid is discharged from the nozzle toward the substrate until the rinsing liquid is removed from the substrate. Can be prevented from being oxidized. In addition, since nitrogen contained in the rinse liquid does not become bubbles, adhesion of contaminants to the substrate is suppressed.

<First Embodiment>
FIG. 1 is a cross-sectional view showing a schematic configuration of the entire substrate processing system according to the first embodiment of the present invention. FIG. 2 is a block diagram showing a control configuration of the substrate processing system of FIG. The substrate processing system includes a substrate processing apparatus 100 and a pure water supply source 200 that is provided separately from the substrate processing apparatus 100 and supplies pure water to the apparatus 100. The substrate processing apparatus 100 supplies a treatment liquid such as hydrofluoric acid to the substrate W to perform a film removal process, performs a rinse process with a rinse liquid such as pure water after the film removal process, and then performs a drying process. The apparatus executes a series of these processes in the same apparatus main body 101. Here, in the rinsing process, pure water supplied from the pure water supply source 200 to the substrate processing apparatus 100 via the pipe 201 is used.

  In the substrate processing apparatus 100, as shown in FIG. 1, the substrate W can be held by the spin chuck 1. The spin chuck 1 includes a disk-shaped base member 2 that also functions as a blocking member on the back side of the substrate, and three or more holding members 3 provided on the upper surface thereof. Each of these holding members 3 includes a support portion 3a for placing and supporting the outer peripheral end portion of the substrate W from below, and a regulating portion 3b for regulating the position of the outer peripheral edge of the substrate W. These holding members 3 are provided in the vicinity of the outer peripheral end of the base member 2. In addition, each regulating portion 3b can take an operation state in which the substrate W is held in contact with the outer peripheral edge of the substrate W and a non-operation state in which the holding of the substrate W is released away from the outer peripheral edge of the substrate W. After the substrate W is loaded / unloaded to / from the support portion 3a by a transfer robot (not shown) in a non-acting state, the substrate W is placed on the support portion 3a with the surface facing up. The substrate W is held by the spin chuck 1 by switching each restricting portion 3b to the operating state. The operation of the holding member 3 (the restricting portion 3b) can be realized by, for example, a link mechanism disclosed in Japanese Patent Laid-Open No. 63-1553839.

  An upper end portion of the rotating shaft 4 is attached to the lower surface of the base member 2. A pulley 5a is fixed to the lower end portion of the rotating shaft 4, and a rotational driving force of the motor 5 is interposed between the pulley 5a and a pulley 5b fixed to the rotating shaft of the motor 5 via a belt 5c. It is configured to be transmitted to the rotating shaft 4. Therefore, the substrate W held on the spin chuck 1 is rotated around the center of the substrate W by driving the motor 5.

  A nozzle 6 is provided at the center of the base member 2. The nozzle 6 is connected to a liquid supply section 50 for supplying a processing liquid and a rinsing liquid to the back surface of the substrate via a pipe 7 inscribed along the central axis of the hollow rotating shaft 4 and the pipe 8. The configuration and operation of the liquid supply unit 50 will be described later.

  In addition, an opening 16 is provided in the center of the base member 2 coaxially with the nozzle 6. The opening 16 is connected to a gas supply unit 20 through a hollow part 17 provided in the rotary shaft 4 coaxially with the pipe 7 and a pipe 19 having an opening / closing valve 18 interposed therebetween. Therefore, by opening the on-off valve 18, an inert gas (for example, nitrogen gas) is supplied between the base member 2 that functions as the “atmosphere blocking means” of the present invention and the back surface of the substrate W. The space can be purged with an inert gas atmosphere.

  Above the spin chuck 1, a blocking member 21 that functions as the “atmosphere blocking means” of the present invention is provided. The blocking member 21 is attached to the lower end portion of the suspension arm 22 disposed in the vertical direction. In addition, a motor 23 is provided at the upper end of the suspension arm 22, and by driving the motor 23, the blocking member 21 is rotated about the suspension arm 22. The rotation axis 4 of the rotation axis 4 of the spin chuck 1 and the rotation axis of the suspension arm 22 coincide with each other and are held by the base member 2 and the blocking member 21 as the atmosphere blocking means and the spin chuck 1. The substrate W is rotated about the same axis. The motor 23 is configured to rotate the blocking member 21 in the same direction as the spin chuck 1 (the substrate W held by the spin chuck 1) and at substantially the same rotational speed.

  A nozzle 25 is provided at the center of the blocking member 21. The nozzle 25 is connected to a liquid supply unit 70 for supplying a processing liquid and a rinsing liquid to the substrate surface via a pipe 26 provided along the central axis of the hollow suspension arm 22 and a pipe 27. The configuration and operation of the liquid supply unit 70 will be described in detail later.

  In addition, an opening 35 is provided at the center of the blocking member 21 coaxially with the nozzle 25. The opening 35 is connected to a gas supply unit 39 through a hollow portion 36 provided in the suspension arm 22 coaxially with the tube 26 and a tube 38 having an opening / closing valve 37 interposed therebetween. Then, in the state where the blocking member 21 is disposed close to the surface of the substrate W held by the spin chuck 1, the on-off valve 37 is opened, so that an inert gas is interposed between the blocking member 21 and the surface of the substrate W. (For example, nitrogen gas) is supplied, and the space can be purged with an inert gas atmosphere. Thus, in this embodiment, the gas supply units 20 and 39 correspond to the “inert gas supply means” of the present invention.

  Next, the configuration of the liquid supply units 50 and 70 will be described. Since the liquid supply units 50 and 70 have the same configuration, the configuration of one liquid supply unit 50 will be described here, and the configuration of the other liquid supply unit 70 will be denoted by a corresponding reference numeral. Description is omitted. The liquid supply unit 50 includes a hydrofluoric acid supply source 51 that supplies hydrofluoric acid, a nitrogen dissolving unit 58, and a deaeration unit 59. A hydrofluoric acid supply source 51 is connected to the mixing unit 55 via a pipe 54 having an on-off valve 53 interposed therebetween, while a pure water supply source 200 provided separately from the substrate processing apparatus 100 is connected via the pipe 201. And connected to the inlet of the nitrogen dissolving unit 58. Further, the nitrogen dissolving unit 58 is provided with another inlet, and is connected to a nitrogen gas supply source (not shown). Then, nitrogen gas from the nitrogen gas supply source is dissolved in the supersaturated state with respect to the pure water from the pure water supply source 200 to generate nitrogen-rich pure water. Further, the nitrogen dissolving unit 58 is connected to the mixing unit 55 via a pipe 57 having a deaeration unit 59 and an opening / closing valve 56 interposed therebetween. For this reason, a part of nitrogen is degassed from the pure water enriched with nitrogen by the nitrogen dissolving unit 58, and the pure water whose nitrogen solubility is adjusted in this way can be supplied to the mixing unit 55 through the on-off valve 56. It has become.

  Then, a hydrofluoric acid solution or pure water is selectively directed from the mixing unit 55 to the pipe 8 toward the surface of the substrate W by switching the opening / closing valves 53 and 56 according to a control command from the control unit 80 for controlling the entire apparatus. Can be supplied. That is, when all the on-off valves 53 and 56 are opened, hydrofluoric acid and pure water are supplied to the mixing unit 55 to prepare a hydrofluoric acid aqueous solution having a predetermined concentration. Then, this hydrofluoric acid aqueous solution is discharged from the nozzle 6 toward the back surface of the substrate W through the tube 8, and the film adhering to the back surface of the substrate is removed by etching. When only the opening / closing valve 56 is opened, pure water is supplied from the nozzle 6 to the back surface of the substrate W through the pipe 8 to perform the rinsing process.

  Thus, on the back side of the substrate W, the liquid supply unit 50, the tube 8, and the nozzle 6 function as the “rinsing means” of the present invention, and the nitrogen dissolving unit 58 serves as the “rinsing liquid generating means” of the present invention. Further, the deaeration unit 59 functions as the “deaeration means” of the present invention. For the nitrogen dissolving unit 58, for example, a bubbling device using a tank or an existing device using a hollow fiber is used. As for the surface side of the substrate W, the liquid supply unit 70, the tube 27, and the nozzle 25 function as the “rinsing means” of the present invention, and the nitrogen dissolving unit 78 serves as the “rinsing liquid generating means” of the present invention. The deaeration unit 79 functions as the “deaeration means” of the present invention.

  A cup 40 is disposed around the spin chuck 1 to prevent the processing liquid from scattering around the spin chuck 1. The processing liquid collected in the cup 40 is drained out of the apparatus and stored in a tank (not shown) provided below the cup 40.

  Here, the pure water supply source 200 is connected to the nitrogen dissolution unit 58 and the deaeration unit 59 so that the pure water supplied from the pure water supply source 200 is dissolved in nitrogen, and then deaerated to the substrate W from the nozzles 6 and 25. The reason for the configuration is as follows. The pure water supplied from the pure water supply source 200 toward the substrate processing apparatus 100 is degassed by a degassing processing facility (not shown) adjacent to the factory where the substrate processing apparatus 100 is installed. The dissolved oxygen concentration in pure water is reduced. However, when the pure water supplied from the pure water supply source 200 is used as it is as the rinsing liquid (or the diluting liquid for diluting the hydrofluoric acid supplied from the hydrofluoric acid supply source 51), the nozzle in the substrate processing apparatus 100 is used. The pure water discharged from No. 6 is exposed to air, so that even if the dissolved oxygen concentration of pure water is reduced by degassing in advance, the oxygen in the air dissolves immediately after discharge, so that the pure water is dissolved. The oxygen concentration increases rapidly. As a result, the surface of the substrate W is oxidized while the surface of the substrate W is wet with pure water, that is, within a period (for example, about 30 seconds) from the start of the rinsing process to the end of the drying process. .

  Therefore, pure water supplied from the pure water supply source 200 is sent to the nitrogen dissolving unit 58, and nitrogen is added to the pure water by the nitrogen dissolving unit 58 in a supersaturated manner, so that pure water containing nitrogen exceeding the solubility limit is added. Is generated. Thereby, pure water having a low dissolved oxygen concentration can be easily obtained. In addition, the dissolved oxygen concentration is effectively prevented from increasing by dissolving nitrogen in pure water. On the other hand, when nitrogen is added to supersaturation, there is a problem that a part of nitrogen contained in pure water becomes bubbles and particles or the like adhere to the surface of the substrate W. For this reason, pure water added with nitrogen by the nitrogen dissolving unit 58 is sent to the deaeration unit 59, and a part of the nitrogen is supplied from the pure water so that the nitrogen contained in the pure water is below the solubility limit by the deaeration unit 59. Is degassing. Thereby, a part of nitrogen contained in the pure water becomes bubbles, and particles and the like are prevented from adhering to the surface of the substrate W.

  Next, the operation of the substrate processing system configured as described above will be described with reference to FIG. FIG. 3 is a flowchart showing the operation of the substrate processing system of FIG. In the substrate processing apparatus 100, after the unprocessed substrate W is transferred to the spin chuck 1 by the transfer robot and held by the holding member 3 (Step S <b> 1), each part of the apparatus is controlled as follows by the control unit 80 that controls the entire apparatus. The film removal process, the rinse process, and the drying process are performed in this order under control.

  In step S2, after the blocking member 21 is disposed close to the surface of the substrate W held by the spin chuck 1, the driving of the motor 5 is started with the substrate W sandwiched between the base member 2 and the blocking member 21. Then, the substrate W is rotated together with the spin chuck 1. In addition, all the on-off valves 53, 73, 56, and 76 are opened to supply hydrofluoric acid and pure water to the mixing units 55 and 75 to prepare a hydrofluoric acid aqueous solution having a predetermined concentration. To pump. Here, the pure water supplied to the mixing units 55 and 75 is added with nitrogen exceeding the solubility limit by the nitrogen dissolving units 58 and 78, and the nitrogen contained in the pure water is dissolved by the degassing units 59 and 79. Part of the nitrogen is degassed from the pure water so that it becomes:

  The hydrofluoric acid aqueous solution pumped to the nozzles 6 and 25 is discharged from the nozzles 6 and 25 and supply of the hydrofluoric acid aqueous solution to both surfaces of the substrate W is started (step S3). Thereby, the etching removal of the film adhering to both surfaces of the substrate W is started. Thus, in this embodiment, the film removal step corresponds to the “wet treatment step” of the present invention.

  When it is confirmed in step S4 that the film removal process is completed, all the on-off valves 53, 73, 56, and 76 are closed, and the supply of the hydrofluoric acid aqueous solution from the nozzles 6 and 25 to the substrate W is stopped. Is rotated at a high speed, and the hydrofluoric acid aqueous solution is shaken off to drain out of the apparatus.

  When the draining of the hydrofluoric acid aqueous solution is thus completed (step S5), the on-off valves 18 and 37 are opened, and an inert gas is supplied to the space between the substrate W and the base member 2 and the blocking member 21. After the atmosphere around the substrate W is changed to an inert gas atmosphere, the on-off valves 56 and 76 are opened for a predetermined time, and pure water is supplied as a rinsing liquid to both main surfaces of the substrate W to rinse the substrate W (“ Corresponding to a “rinsing step”) (step S6). Here, pure water supplied to the substrate W is preliminarily added with nitrogen by the nitrogen dissolving units 58 and 78 to generate pure water as a rinsing liquid containing nitrogen exceeding the solubility limit ( And a part of nitrogen is degassed from the pure water so that the nitrogen contained in the pure water is below the solubility limit by the degassing units 59 and 79 (“degassing process”). Equivalent). Therefore, it is suppressed that the dissolved oxygen concentration of pure water increases immediately after the discharge from the nozzles 6 and 25.

  After the rinsing process is completed by closing the on-off valves 56 and 76, the substrate W is continuously rotated until the substrate W is dried. After the drying of the substrate W is finished, the rotation of the substrate is stopped and the on-off valves 18 and 37 are closed. The supply of inert gas is stopped (step S7). Here, the pure water as the rinsing liquid is present in the substrate W until the subsequent drying process (step S7) is completed as well as during the rinsing process (step S6). It is necessary to consider the dissolved oxygen concentration of pure water during the period until the treatment is completed. However, even during this period, the increase in dissolved oxygen concentration of pure water is suppressed by dissolved nitrogen in pure water. As a result, from the start of the rinsing process to the completion of the drying process (for example, about 30 seconds), the dissolved oxygen in the pure water present on the substrate W remains at a low level. Generation of an oxide film on the substrate W can be prevented.

  Thus, when a series of substrate processing (film removal processing, rinsing processing and drying processing) is completed, the blocking member 21 is separated from the surface of the substrate W held by the spin chuck 1 and the substrate holding by the holding member 3 is released. Thereafter, the transfer robot carries the processed substrate W to the next substrate processing apparatus (step S8).

  As described above, according to this embodiment, prior to the rinsing process, nitrogen is supersaturated in pure water to generate a rinsing liquid containing nitrogen exceeding the solubility limit, and the generated rinsing liquid is further dissolved. Since a part of nitrogen is degassed from the rinse liquid so as to be below the limit to generate a degassed rinse liquid, the following effects can be obtained. That is, it is possible to easily reduce the dissolved oxygen concentration of pure water as a rinse liquid by adding nitrogen to the pure water in a supersaturated manner. In addition, the degassed rinse liquid is exposed to air as soon as it is discharged from the nozzles 6 and 25, leading to an increase in dissolved oxygen concentration, but the rising speed is suppressed by the dissolved nitrogen in the rinse liquid. As a result, since the dissolved oxygen concentration of the rinsing liquid is kept at a low level during the period from the start of the rinsing process to the end of the drying process (for example, about 30 seconds), the oxidation of the substrate W can be effectively prevented. it can. In addition, since a part of the nitrogen is degassed from the rinse liquid so that the nitrogen concentration in the rinse liquid is below the solubility limit, nitrogen in the rinse liquid supplied to the surface of the substrate W may become bubbles. In addition, adhesion of particles or the like to the substrate W is suppressed.

  In addition, since the atmosphere around the substrate W is an inert gas atmosphere during the rinsing process and the drying process, the amount of oxygen around the substrate W dissolved in the rinsing liquid can be reduced. Therefore, it is possible to further suppress an increase in the dissolved oxygen concentration of the rinsing liquid during the period from the start of the rinsing process to the end of the drying process. As a result, generation of an oxide film on the substrate W can be more effectively suppressed.

Second Embodiment
FIG. 4 is a partial configuration diagram showing a second embodiment of the substrate processing system according to the present invention. The second embodiment is greatly different from the first embodiment in that the first embodiment is a so-called single-wafer type in which the substrates W are processed one by one, whereas the second embodiment has a plurality of types. This is a so-called batch type in which the substrates W are collectively processed. In this batch-type substrate processing system, for example, an etching solution (hydrofluoric acid aqueous solution or the like) is used to perform a series of various processing (film removal processing, rinsing processing, drying processing using a processing solution) on a plurality of substrates W. The film removal processing tank for storing the processing liquid, etc., the film removal processing tank for performing the film removal processing on the substrate W, the rinsing processing tank for storing the pure water as the rinsing liquid, and rinsing the substrate W, and the substrate W by spin drying or the like A drying treatment tank for drying is provided. FIG. 4 shows a substrate processing system related to the rinsing process.

  The rinse treatment tank 91 shown in FIG. 4 performs a rinse process for washing away the treatment liquid adhering to the surface of the substrate W and the particles generated thereby after the film removal process is performed in the film removal treatment tank. Specifically, the plurality of substrates W processed in the film removal processing tank are transferred to the lifter device 92 that can be held by the three arms 92a, and the lifter device 92 is lowered in the rinsing processing tank 91. Is immersed in a rinse solution. Pure water, which is a rinsing liquid, was disposed in the rinsing tank 91 in parallel to the left and right at the bottom of the tank through the pipe 93 for supplying the rinsing liquid supplied from the bottom of the tank and the branch pipes 93a and 93b. The two rinse liquid supply portions 94a and 94b are respectively ejected toward the center side. Each of the pair of rinse liquid supply units 94a and 94b has a plurality of nozzles (not shown) for discharging the rinse liquid between the substrates W from the lower left and right sides of the plurality of substrates W immersed in the processing liquid. The rinsing liquid discharged from each nozzle between the nozzles rises while the rinsing liquid spouted from both the left and right sides forms an upward flow at the center of the tank, and the opening at the top of the tank It overflows from the part. Contaminants such as particles generated by the processing liquid due to the overflow are received in the overflow tanks 95a and 95b together with the processing liquid and pure water, and discharged out of the tank.

  Next, the configuration of the liquid supply unit 50 will be described. The configuration of the liquid supply unit 50 is basically the same as that of the previous embodiment, except that there is no hydrofluoric acid supply system that supplies hydrofluoric acid as a processing liquid (these are provided in the film removal processing tank). is there. That is, the pure water supply source 200 provided separately from the substrate processing apparatus 100 is connected to the nitrogen dissolving unit 58 via the pipe 201, and the deaeration unit 59 further includes the pipe 93 provided with the on-off valve 56, The rinsing liquid supply parts 94a and 94b are connected via the branch pipes 93a and 93b.

  The rinse treatment tank 91 is accommodated in a sealed structure 96, and a gas supply unit 20 is connected to the sealed structure 96 through a pipe 19 having an on-off valve 18 interposed therebetween. For this reason, by opening the on-off valve 18, an inert gas (such as nitrogen) is supplied into the sealed structure 96 to fill the vicinity of the rinsing treatment tank 91 with the inert gas, and from an exhaust port (not shown). It is configured to be purged.

  Also in the substrate processing system configured as described above, pure water which is a rinsing liquid is supplied to the plurality of substrates W immersed in the rinsing processing tank 91 in the same manner as in the first embodiment, and the same as in the first embodiment. The effect is obtained. That is, the pure water supplied from the pure water supply source 200 is supersaturated with nitrogen added by the nitrogen dissolving unit 58, and pure water is generated as a rinsing liquid containing nitrogen exceeding the solubility limit. For this reason, pure water having a low dissolved oxygen concentration can be easily obtained. Further, by dissolving nitrogen in pure water, an increase in the dissolved oxygen concentration of pure water, which is a rinse liquid, is effectively prevented. Moreover, since the pure water added with nitrogen is deaerated by the deaeration unit 59 so that the nitrogen contained in the pure water is below the solubility limit, it is included in the pure water discharged from the nozzle as the rinse liquid. Part of the generated nitrogen becomes bubbles, and particles and the like are prevented from adhering to the surface of the substrate W.

  In addition, since the vicinity of the periphery of the rinsing treatment tank 91 is an inert gas atmosphere, the amount of oxygen dissolved in the pure water that is the rinsing liquid is reduced to further suppress an increase in the dissolved oxygen concentration of the pure water, and the substrate W Oxidation of the substrate W associated with loading / unloading into the rinse treatment tank 91 can be prevented. Therefore, the oxidation of the substrate W can be further effectively prevented.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the first embodiment, a series of processing is performed on both surfaces of the substrate W, but the present invention can be applied to a substrate processing apparatus and a substrate processing system that perform substrate processing on only one surface.

  In the above embodiment, a hydrofluoric acid aqueous solution is supplied as a processing liquid to the substrate W to perform wet processing on the substrate. However, other processing liquids (for example, a cleaning liquid and a developer) are supplied to the substrate to obtain a predetermined process. The present invention can be applied to a substrate processing apparatus that performs wet processing (for example, cleaning processing and development processing). In short, the present invention can be applied to all substrate processing apparatuses and substrate processing systems that perform a rinsing process by supplying a rinsing liquid to a substrate.

  In the above embodiment, pure water is used as the rinse liquid, but ultrapure water may be used instead of pure water. Thereby, processing with higher cleanliness becomes possible.

  Further, in the above embodiment, pure water supplied from the pure water supply source 200 is introduced from the utility of the factory where the substrate processing apparatus 100 is installed to the nitrogen dissolving unit 58, (78) to add nitrogen. Further, a deaeration unit is additionally provided on the substrate processing apparatus 100 side, and pure water supplied from the utility of the factory is deaerated by the added deaeration unit, and then supplied to the nitrogen dissolution unit 58 (78). It may be. By configuring in this way, oxygen dissolved in pure water during the period from the pure water supply source 200 to the substrate processing apparatus 100 via the utility line of the factory is excluded, and the pure oxygen having a lower dissolved oxygen concentration. You can get water.

  Moreover, in the said embodiment, although the produced | generated rinse liquid is supplied to the board | substrate W as it is and the rinse process is performed, the rinse liquid which added the hydrofluoric acid so that the PH value of the produced | generated rinse liquid might be 6 or less The rinse process may be performed using By using such a rinsing liquid, it is possible to prevent the oxidation of the substrate W (generation of a watermark). In this case, a predetermined amount of hydrofluoric acid is added to the rinse liquid during the rinse treatment. For example, in the first embodiment, a predetermined amount of hydrofluoric acid is added to the rinse liquid by opening the on-off valve 56 and adjusting the on-off valve 53 during the rinsing process. Thereby, the rinse liquid can be controlled to a desired PH value. The PH value is not limited to the case where the pH value is controlled after the rinse liquid is generated (nitrogen is added to the pure water), but the PH value may be controlled in advance before adding nitrogen to the pure water. Further, the acid used for controlling the PH value of the rinse liquid is not limited to hydrofluoric acid, and for example, hydrochloric acid may be used.

  The present invention is applicable to a substrate processing apparatus and a substrate processing system that perform a rinsing process on a substrate using pure water as a rinsing liquid after supplying a processing liquid to the substrate and performing a predetermined wet process. ing.

1 is a longitudinal sectional view showing a schematic configuration of an entire substrate processing system according to a first embodiment of the present invention. It is a block diagram which shows the control structure of the substrate processing system of FIG. It is a flowchart which shows operation | movement of the substrate processing system of FIG. It is a partial block diagram which shows 2nd Embodiment of the substrate processing system concerning this invention.

Explanation of symbols

2. Base member (atmosphere blocking means)
6, 25 ... Nozzle (rinsing means)
8, 27 ... Tube (Rinsing means)
20, 39 ... Gas supply section (inert gas supply means)
21. Blocking member (atmosphere blocking means)
50, 70 ... Liquid supply section (rinsing means)
58, 78 ... Nitrogen dissolution unit (rinse solution generating means)
59, 79 ... Deaeration unit (deaeration means)
100: Substrate processing apparatus (substrate processing unit)
101... Device body (unit body)
200: Pure water supply source (pure water supply unit)
W ... Board

Claims (6)

A wet processing step of supplying a processing liquid to the substrate and applying a predetermined wet processing;
A rinsing liquid generating step for generating a rinsing liquid containing nitrogen exceeding the solubility limit by adding nitrogen to pure water in a supersaturated state;
A degassing step of generating a degassed rinse liquid by degassing a part of the nitrogen from the rinse liquid so that the nitrogen contained in the rinse liquid is not more than the solubility limit;
A substrate processing method comprising: a rinsing step of supplying the substrate with the degassed rinse liquid after the wet processing step, thereby rinsing the substrate with the degassed rinse solution. .   The substrate processing method according to claim 1, wherein the rinsing step is performed in an inert gas atmosphere. A rinse liquid generating means for generating nitrogen-rich rinse liquid by adding nitrogen to pure water;
Degassing means for degassing a part of nitrogen from the rinse liquid generated by the rinse liquid generating means to generate a degassed rinse liquid;
A substrate processing comprising: rinsing means for supplying the degassed rinse liquid to the substrate by discharging the degassed rinse liquid toward the substrate from the nozzle and rinsing the substrate. apparatus. An atmosphere blocking means spaced from the substrate while facing the substrate to which the degassed rinse liquid is supplied;
The substrate processing apparatus according to claim 3, further comprising an inert gas supply unit that supplies an inert gas to a space formed between the atmosphere blocking unit and the substrate. A substrate processing comprising: a pure water supply unit that supplies pure water; and a substrate processing unit that is provided separately from the pure water supply unit and that performs a rinsing process on the substrate using pure water supplied from the pure water supply unit. In the system,
The substrate processing unit includes:
Rinsing liquid generating means for generating nitrogen-rich rinse liquid by adding nitrogen to pure water supplied from the pure water supply unit;
Degassing means for degassing a part of nitrogen from the rinse liquid generated by the rinse liquid generating means to generate a degassed rinse liquid;
Rinsing means for supplying the degassed rinse liquid to the substrate by discharging the degassed rinse liquid from the nozzle toward the substrate and rinsing the substrate is provided in the same unit body. A substrate processing system.   The substrate processing unit includes an atmosphere blocking unit spaced from the substrate while facing the substrate to which the rinsing liquid is supplied, and an inert gas in a space formed between the atmosphere blocking unit and the substrate The substrate processing system according to claim 5, further comprising an inert gas supply means for supplying the inside of the unit main body.

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