JP2007234813A - Method and device for processing substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processing method and a substrate processing device which are capable of preventing particles that are objects of counting by a particle counter from occurring on the surface of a substrate for a long time after processing is finished. <P>SOLUTION: SPM is supplied onto the surface of a substrate so as to remove a disused resist pattern from the surface of the substrate. Thereafter, pure water is supplied on the surface of the substrate so as to rinse out SPM from the surface of the substrate. Pure water attached to the substrate is removed once, and then pure water is supplied on the surface of the substrate. Even if a sulphuric acid component remains unremoved after SPM is removed by the use of pure water, the sulphuric acid component staying on the surface of the substrate is dried out when the pure water is removed once. The dried sulphuric acid component absorbs moisture quickly, so that the sulphuric acid component grows rapidly in grain diameter, and the sulphuric acid component becomes easy to separate from the surface of the substrate. Therefore, when pure water is supplied again onto the surface of the substrate, the sulphuric acid component staying on the surface of the substrate is easily eliminated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a substrate processing method and a substrate processing apparatus for processing a surface of various substrates such as a semiconductor wafer with a processing liquid prepared by mixing sulfuric acid and hydrogen peroxide solution.

  Semiconductor device manufacturing processes include a process of selectively etching an oxide film or the like formed on the surface of a semiconductor wafer (hereinafter simply referred to as “wafer”), and impurities such as phosphorus, arsenic, and boron on the surface of the wafer. A step of locally implanting (ions) is included. In these processes, a resist pattern made of an organic material such as a photosensitive resin is formed on the outermost surface of the wafer in order to prevent etching or ion implantation to an undesired portion, and a portion where etching or ion implantation is not desired is resist. Masked by. Since the resist formed on the wafer becomes unnecessary after the etching or ion implantation, a process for removing the unnecessary resist on the wafer is performed after the etching or ion implantation.

  As a method of this processing, there are a batch type in which a plurality of substrates are processed at once and a single wafer type in which substrates are processed one by one. Conventionally, the batch type has been the mainstream, but since the batch type requires a large processing tank that can accommodate a plurality of substrates, the substrates to be processed have recently been becoming larger. Thus, a single-wafer type that does not require such a large treatment tank has attracted attention.

In the single-wafer type resist removal process, for example, sulfuric acid and hydrogen peroxide are mixed in the center of the wafer surface while the wafer is rotated at a constant rotation speed around a rotation axis perpendicular to the center. SPM (sulfuric acid / hydrogen peroxide mixture) is prepared. The SPM supplied to the surface of the wafer receives centrifugal force from the rotation of the wafer, flows on the surface of the wafer from the central portion toward the peripheral edge, and quickly spreads over the entire surface of the wafer. The resist formed on the surface of the wafer is peeled off from the surface of the wafer by the strong oxidizing power of caroic acid (peroxomonosulfuric acid) contained in the SPM. When the supply of SPM is continued for a predetermined time, the supply of SPM is stopped, and pure water is supplied to the surface of the wafer, so that the SPM adhering to the wafer is washed away. Thereafter, the wafer is dried by being rotated at a high speed, and a series of resist removal processing is completed (see, for example, Patent Document 1).
JP 2005-93926 A

However, when the present inventor examined the number of particles adhering to the surface of the wafer immediately after the resist removal process was completed using a particle counter, the particles were hardly counted immediately after the process was completed, but several hours after the process was completed. It has been found that as the time elapses, a large number of particles are counted.
The cause of the generation of particles is not necessarily clear, but since the sulfuric acid contained in the SPM has a high viscosity, the sulfuric acid component remaining on the wafer surface cannot be completely removed by simply supplying pure water. However, it is assumed that moisture in the atmosphere may be absorbed and the surface of the wafer expands to a particle size to be counted by the particle counter.

  The present invention has been made under such a background, and an object of the present invention is to provide a substrate processing method that does not cause generation of particles to be counted by the particle counter on the surface of the substrate even after a lapse of time from the end of the processing. It is to provide a substrate processing apparatus.

  In order to achieve the above object, the invention according to claim 1 includes a treatment liquid supply step (S1) for supplying a treatment liquid prepared by mixing sulfuric acid and hydrogen peroxide solution on the surface of the substrate (W). The first rinsing liquid supply step (S2) for supplying a rinsing liquid to the surface of the substrate after the treatment liquid supplying step and the rinsing liquid adhering to the substrate after the first rinsing liquid supplying step are removed. After the first rinsing liquid removing step (S3), the second rinsing liquid supplying step (S4) for supplying the rinsing liquid to the surface of the substrate again after the first rinsing liquid removing step, and the second rinsing liquid supplying step. A substrate processing method characterized by including a second rinse liquid removing step (S5) for removing the rinse liquid adhering to the substrate later.

In addition, the alphanumeric characters in parentheses represent corresponding components in the embodiments described later. The same applies hereinafter.
In this method, first, a treatment liquid prepared by mixing sulfuric acid and hydrogen peroxide solution is supplied to the surface of a substrate. A treatment liquid prepared by mixing sulfuric acid and hydrogen peroxide water, that is, SPM contains caroic acid having strong oxidizing power. Therefore, when a resist is formed on the surface of the substrate, when the processing liquid is supplied to the surface of the substrate, the processing liquid and the resist react to peel the resist from the surface of the substrate. Next, the rinsing liquid is supplied to the surface of the substrate, so that the processing liquid adhering to the surface of the substrate is washed away. And after the rinse liquid adhering to a board | substrate is once removed, the rinse liquid is again supplied to the surface of the board | substrate.

  Once the rinse liquid adhering to the substrate is removed, even if the sulfuric acid component remains on the surface of the substrate, the remaining sulfuric acid component is dried. The dried sulfuric acid component rapidly absorbs moisture, so that the particle size grows at once and becomes easy to peel off from the surface of the substrate. Therefore, once the rinse liquid adhering to the substrate is removed and then the rinse liquid is supplied again to the surface of the substrate, the sulfuric acid component remaining on the surface of the substrate is easily removed. Therefore, even if the rinse liquid adhering to the substrate is removed again and the substrate is left to stand, there is no possibility that particles that are counted by the particle counter are generated on the surface of the substrate.

According to a second aspect of the present invention, in the substrate processing method according to the first aspect, the second rinsing liquid supply step is a step of supplying a rinsing liquid to which ultrasonic vibration is applied to the surface of the substrate. It is.
According to this method, peeling of the sulfuric acid component from the surface of the substrate can be promoted by the ultrasonic vibration applied to the rinsing liquid. For this reason, the sulfuric acid component remaining on the surface of the substrate can be eliminated more favorably, and the generation of particles that are counted by the particle counter can be further prevented.

According to a third aspect of the present invention, in the substrate processing according to the first or second aspect, the second rinsing liquid supply step is a step of supplying a mixed fluid of a rinsing liquid and a gas to the surface of the substrate. Is the method.
According to this method, since the mixed fluid generated by mixing the rinsing liquid and the gas has a large physical energy, the mixed fluid is supplied to the surface of the substrate. The peeling of components can be promoted. Therefore, the sulfuric acid component remaining on the surface of the substrate can be eliminated more favorably, and the generation of particles that are counted by the particle counter can be prevented even better.

The invention according to claim 4 is characterized in that, in the second rinsing liquid supply step, the rinsing liquid is supplied to the surface of the substrate at a flow rate larger than the supply flow rate of the rinsing liquid in the first rinsing liquid supply step. A substrate processing method according to any one of claims 1 to 3.
According to this method, since the rinsing liquid supplied to the surface of the substrate has a larger physical energy as the supply flow rate is larger, the rinsing liquid is supplied to the surface of the substrate at a higher flow rate. The remaining sulfuric acid component can be washed away more strongly. Therefore, the sulfuric acid component remaining on the surface of the substrate can be eliminated more favorably, and the generation of particles that are counted by the particle counter can be prevented even better.

A fifth aspect of the present invention is the substrate processing method according to any one of the first to fourth aspects, wherein an alkaline liquid is used as the rinse liquid in the second rinse liquid supply step.
According to this method, the sulfuric acid component remaining on the surface of the substrate is reacted with an alkaline solution used as a rinsing liquid to form a salt, and the salt is washed away from the surface of the substrate by rinsing the salt with the rinsing liquid. Can be eliminated more easily.

  The invention according to claim 6 is a substrate holding means (11, 41) for holding the substrate (W) substantially horizontally, a substrate rotating means (14, 43) for rotating the substrate held by the substrate holding means, A processing liquid supply means (12, 20, 21) for supplying a processing liquid prepared by mixing sulfuric acid and hydrogen peroxide solution on the surface of the substrate held by the substrate holding means, and held by the substrate holding means Rinsing liquid supply means (23, 24, 25, 26, 47, 48, 49, 50; 61, 62, 63, 64, 65) for supplying a rinsing liquid to the surface of the substrate, and a processing liquid on the surface of the substrate After the rinsing liquid is supplied in this order, the rinsing liquid adhering to the substrate is shaken off by the rotation of the substrate, and the rinsing liquid is supplied again to the surface of the substrate, and then the substrate is rotated by the rotation of the substrate. Adhering rinse liquid is shaken off As the substrate rotating means, characterized in that it comprises a said processing liquid supply means and control means for controlling the rinsing liquid supply means (60), a substrate processing apparatus.

  According to this configuration, an effect similar to the effect described in relation to claim 1 can be achieved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic plan view showing a layout of a substrate processing apparatus according to an embodiment of the present invention.
This substrate processing apparatus is a single-wafer type apparatus that processes wafers W as an example of a substrate one by one, and includes a processing unit PC and an indexer unit IND coupled to the processing unit PC.

The processing section PC includes a transport path TP, two SPM processing sections 1 facing each other across the transport path TP, and a rinse processing section facing each other across the transport path TP and adjacent to each SPM processing section 1 2 are arranged.
A transport robot TR is disposed on the transport path TP. The transfer robot TR can carry the wafer W into and out of the SPM processing unit 1 and the rinse processing unit 2.

On the opposite side of the indexer unit IND from the processing unit PC, there is provided a cassette mounting unit (not shown) in which a plurality of cassettes are arranged side by side. The cassette is used when the wafer W is transported in a factory where the substrate processing apparatus is installed, and can accommodate a plurality of wafers W stacked in multiple stages.
An indexer robot IR is arranged in the indexer unit IND. The indexer robot IR can access each cassette arranged on the cassette mounting portion, take out the wafer W from the cassette, and store the wafer W in the cassette. Further, the indexer robot IR can deliver the wafer W to and from the transfer robot TR.

FIG. 2 is a schematic side view showing the configuration of the SPM processing unit 1.
The SPM processing unit 1 includes a spin chuck 11 that holds the wafer W substantially horizontally, and sulfuric acid (H ₂ SO ₄ ) and hydrogen peroxide (H ₂ O) on the surface (upper surface) of the wafer W held by the spin chuck 11. ₂ ) and a blocking plate 13 for controlling the atmosphere in the vicinity of the surface of the wafer W held by the spin chuck 11.

The spin chuck 11 is provided at substantially equal angular intervals at a plurality of locations around the motor 14, a disc-shaped spin base 15 that is rotated around the vertical axis by the driving force of the motor 14, and the periphery of the spin base 15. And a plurality of clamping members 16 for clamping the wafer W in a substantially horizontal posture.
When the motor 14 is driven in a state where the wafer W is held by the plurality of holding members 16, the spin base 15 is rotated around the vertical axis by the driving force, and the wafer W is substantially horizontal with the spin base 15. It is rotated around the vertical axis while maintaining its posture.

The spin chuck 11 is not limited to such a configuration. For example, the back surface (non-device surface) of the wafer W is vacuum-sucked to hold the wafer W in a horizontal posture, and in that state. A vacuum chuck of a vacuum suction type that can rotate the wafer W held by rotating around a vertical axis may be employed.
The SPM nozzle 12 is attached to the tip of an arm 17 that extends substantially horizontally above the spin chuck 11. The arm 17 is supported by an arm support shaft 18 extending substantially vertically on the side of the spin chuck 11. Further, an SPM nozzle drive mechanism 19 is coupled to the arm support shaft 18, and the arm support shaft 18 can be rotated by the driving force of the SPM nozzle drive mechanism 19 to swing the arm 17. It is like that.

  An SPM supply pipe 20 is connected to the SPM nozzle 12, and SPM is supplied through the SPM supply pipe 20. The SPM flowing through the SPM supply pipe 20 may be created by mixing sulfuric acid and hydrogen peroxide solution in a pipe connected to the SPM supply pipe 20, or sulfuric acid and hydrogen peroxide solution may be stored in a tank. It may be created by mixing in and stored in the tank. An SPM valve 21 is interposed in the middle of the SPM supply pipe 20.

The blocking plate 13 is formed in a disc shape having a diameter substantially equal to or larger than that of the wafer W, and is disposed substantially horizontally above the spin chuck 11. On the upper surface of the blocking plate 13, a rotation shaft 22 centering on a vertical axis common to the spin base 15 is fixed. The rotating shaft 22 is formed in a hollow shape, and a pure water circulation pipe 23 is inserted into the hollow interior.
A pure water supply pipe 24 is connected to the pure water circulation pipe 23, and pure water is supplied through the pure water supply pipe 24. A pure water valve 25 is interposed in the middle of the pure water supply pipe 24. Moreover, the pure water circulation pipe 23 extends to the lower surface of the blocking plate 13, and the tip thereof forms a pure water nozzle 26 for discharging pure water.

A nitrogen gas flow passage 27 through which nitrogen gas flows is formed between the inner wall surface of the rotating shaft 22 and the pure water supply pipe 24. A nitrogen gas supply pipe 28 is connected to the nitrogen gas flow passage 27, and nitrogen gas is supplied through the nitrogen gas supply pipe 28. A nitrogen gas valve 29 is interposed in the middle of the nitrogen gas supply pipe 28.
The rotating shaft 22 is attached in a state where it is suspended from the vicinity of the tip of an arm 30 that extends substantially horizontally. The arm 30 is close to the surface of the wafer W held by the spin chuck 11 at a position (a position shown in FIG. 2) where the blocking plate 13 is largely separated above the spin chuck 11 with a minute gap. A blocking plate raising / lowering mechanism 31 for raising and lowering the position is coupled. Further, in relation to the arm 30, a blocking plate rotation drive mechanism 32 for rotating the blocking plate 13 in synchronization with the rotation of the wafer W by the spin chuck 11 is provided.

FIG. 3 is a schematic side view showing the configuration of the rinse treatment unit 2.
The rinse treatment unit 2 includes a spin chuck 41 that holds the wafer W substantially horizontally and a blocking plate 42 that controls the atmosphere near the surface of the wafer W held by the spin chuck 41.
The spin chuck 41 has the same configuration as that of the spin chuck 11 provided in the SPM processing unit 1. That is, the motor 43, the disk-shaped spin base 44 rotated around the vertical axis by the driving force of the motor 43, and a plurality of peripheral portions of the spin base 44 are provided at substantially equal angular intervals, and the wafer W is mounted. And a plurality of clamping members 45 for clamping in a substantially horizontal posture.

The spin chuck 41 also holds the wafer W in a horizontal posture by vacuum-sucking the back surface (non-device surface) of the wafer W, and further rotates around the vertical axis in that state. A vacuum suction type vacuum chuck capable of rotating the held wafer W may be employed.
The blocking plate 42 is formed in a disc shape having a diameter substantially equal to or larger than that of the wafer W, and is disposed substantially horizontally above the spin chuck 41. On the upper surface of the blocking plate 42, a rotation shaft 46 centered on a vertical axis common to the spin base 44 is fixed. The rotating shaft 46 is formed in a hollow shape, and a pure water circulation pipe 47 is inserted into the hollow portion.

A pure water supply pipe 48 is connected to the pure water distribution pipe 47, and pure water is supplied through the pure water supply pipe 48. A pure water valve 49 is interposed in the middle of the pure water supply pipe 48. Further, the pure water circulation pipe 47 extends to the lower surface of the blocking plate 42, and the tip thereof forms a pure water nozzle 50 for discharging pure water.
A nitrogen gas flow passage 51 through which nitrogen gas flows is formed between the inner wall surface of the rotating shaft 46 and the pure water supply pipe 48. A nitrogen gas supply pipe 52 is connected to the nitrogen gas flow passage 51, and nitrogen gas is supplied through the nitrogen gas supply pipe 52. A nitrogen gas valve 53 is interposed in the middle of the nitrogen gas supply pipe 52.

  The rotating shaft 46 is attached in a state where it is suspended from the vicinity of the tip of an arm 54 that extends substantially horizontally. The arm 54 is close to the surface of the wafer W held by the spin chuck 41 at a position where the blocking plate 42 is largely separated above the spin chuck 41 (position shown in FIG. 3) with a minute gap. A blocking plate raising / lowering mechanism 55 for raising and lowering the position is coupled. Further, in connection with the arm 54, a blocking plate rotation drive mechanism 56 is provided for rotating the blocking plate 42 in synchronization with the rotation of the wafer W by the spin chuck 41.

FIG. 4 is a block diagram showing an electrical configuration of the substrate processing apparatus.
This substrate processing apparatus includes a control device 60 including a microcomputer. The control device 60 controls driving of the motors 14 and 43, the SPM nozzle drive mechanism 19, the shield plate rotation drive mechanisms 32 and 56, and the shield plate lifting mechanisms 31 and 55 according to a predetermined program. Moreover, the opening and closing of the SPM valve 21, the pure water valves 25 and 49, and the nitrogen gas valves 29 and 53 are controlled.

FIG. 5 is a process diagram for explaining the flow of processing in this substrate processing apparatus.
When processing the wafer W, the indexer robot IR takes out the wafer W from the cassette. Then, the wafer W taken out from the cassette is transferred from the indexer robot IR to the transfer robot TR, and is transferred into the SPM processing unit 1 by the transfer robot TR.

In the SPM processing unit 1, first, the wafer W is delivered from the transfer robot TR to the spin chuck 11. At this time, the blocking plate 13 is retracted to a position far above the spin chuck 11 so as not to hinder the loading of the wafer W.
When the wafer W is held on the spin chuck 11, the motor 14 is driven and rotation of the wafer W is started. Further, the SPM nozzle drive mechanism 19 is driven, and the SPM nozzle 12 is disposed above the wafer W held by the spin chuck 11. Then, the SPM valve 21 is opened, and SPM is supplied from the SPM nozzle 12 to the surface of the rotating wafer W (SPM processing: step S1).

  At this time, the SPM nozzle 12 may be stopped above the wafer W, and SPM may be supplied from the SPM nozzle 12 to the central portion (near the rotation center) of the surface of the wafer W. In this case, the SPM supplied to the central portion of the surface of the wafer W receives centrifugal force due to the rotation of the wafer W, flows on the surface of the wafer W toward the periphery, and spreads over the entire surface of the wafer W. Further, the arm 17 may be swung within a predetermined angle range by the control of the SPM nozzle driving mechanism 19, and the SPM nozzle 12 may be reciprocated between the rotation center of the wafer W and the peripheral portion. In this case, the SPM supply position on the surface of the wafer W is reciprocated (scanned) while drawing an arc-shaped locus within a range from the rotation center of the wafer W to the peripheral edge of the wafer W, and the entire surface of the wafer W is scanned. SPM is supplied evenly and promptly. In either case, the SPM is supplied to the entire surface of the wafer W, and the resist is peeled from the entire surface of the wafer W by the strong oxidizing power of caloic acid contained in the SPM. Then, the peeled resist is washed away and removed by the flow of SPM.

When the supply of SPM is continued for a predetermined time (for example, 20 to 120 seconds), the SPM valve 21 is closed and the supply of SPM from the SPM nozzle 12 to the wafer W is stopped. When the supply of SPM is stopped, the SPM nozzle 12 is retracted to a position off the upper side of the wafer W.
Thereafter, the shield plate lifting mechanism 31 is driven to lower the shield plate 13 to a position close to the surface of the wafer W. Then, the pure water valve 25 is opened, and pure water is supplied from the pure water nozzle 26 to the center of the surface of the wafer W. At this time, the flow rate of pure water discharged from the pure water nozzle 26 is, for example, 2 liters per minute. Further, the wafer W is rotated at a rotational speed of 1000 rpm, for example, following the SPM processing step. Further, the blocking plate 13 is rotated in the same direction as the wafer W by the blocking plate rotation drive mechanism 32. The pure water supplied on the surface of the wafer W receives a centrifugal force due to the rotation of the wafer W and flows on the surface of the wafer W from the center toward the periphery. As a result, pure water quickly spreads over the entire surface of the wafer W, and SPM adhering to the surface of the wafer W is washed away by the pure water (first rinsing process: step S2).

  For example, after 60 seconds have elapsed after the start of the supply of pure water, the pure water valve 25 is closed. Thereafter, the shielding plate 13 is disposed close to the surface of the wafer W, and the nitrogen gas valve 29 is opened while being rotated in the same direction as the wafer W, so that nitrogen gas is supplied to the center of the surface of the wafer W. . Then, the rotational speed of the wafer W is increased to a predetermined spin dry rotational speed (for example, 2500 rpm), and pure water is supplied from the surface of the wafer W with the nitrogen gas filled between the wafer W and the shielding plate 13. A first spin dry process for shaking off with a centrifugal force is performed (step S3). This first spin dry process is continued for 30 seconds, for example.

After the first spin-drying process, the motor 14 is stopped, the shield plate lifting mechanism 31 is driven, and the shield plate 13 is retracted to a position far above the spin chuck 11. When the wafer W is stationary, the wafer W is unloaded from the SPM processing unit 1 by the transfer robot TR.
The wafer W that has undergone the processing in the SPM processing unit 1 is carried into the rinse processing unit 2 by the transfer robot TR.

In the rinse processing unit 2, first, the wafer W is delivered from the transfer robot TR to the spin chuck 41. At this time, the blocking plate 42 is retracted to a position far above the spin chuck 41 so as not to hinder the loading of the wafer W.
When the wafer W is held on the spin chuck 41, the motor 43 is driven to start the rotation of the wafer W. Further, the shield plate lifting mechanism 55 is driven, and the shield plate 42 is lowered to a position close to the surface of the wafer W. Then, the pure water valve 49 is opened, and pure water is supplied from the pure water nozzle 50 to the center of the surface of the wafer W. At this time, the flow rate of pure water discharged from the pure water nozzle 50 is, for example, 4 liters per minute. The wafer W is rotated at a rotational speed of 1000 rpm, for example. At this time, the blocking plate 42 is rotated in the same direction as the wafer W by the blocking plate rotation drive mechanism 56. The pure water supplied on the surface of the wafer W receives a centrifugal force due to the rotation of the wafer W and flows on the surface of the wafer W from the center toward the periphery. Thereby, pure water quickly spreads over the entire surface of the wafer W, and the surface of the wafer W is washed with pure water (second rinsing process: step S4).

  For example, after 60 seconds have elapsed after the start of the supply of pure water, the pure water valve 49 is closed. Then, the shielding plate 42 is disposed close to the surface of the wafer W, and the nitrogen gas valve 53 is opened while being rotated in the same direction as the wafer W, so that nitrogen gas is supplied to the center of the surface of the wafer W. . Then, the rotational speed of the wafer W is increased to a predetermined spin dry rotational speed (for example, 2500 rpm), and pure water is supplied from the surface of the wafer W with the nitrogen gas filled between the wafer W and the shielding plate 42. A second spin dry process for shaking off by centrifugal force is performed (step S5). This second spin dry process is continued for 30 seconds, for example.

After the second spin dry process, the motor 43 is stopped, the blocking plate lifting mechanism 55 is driven, and the blocking plate 42 is retracted to a position far apart above the spin chuck 11. When the wafer W is stationary, the wafer W is unloaded from the rinse processing unit 2 by the transfer robot TR.
The wafer W that has been processed by the rinse processing unit 2 is transferred from the transfer robot TR to the indexer robot IR, and is stored in one of the cassettes by the indexer robot IR.

  As described above, in this substrate processing apparatus, first, the wafer W is loaded into the SPM processing unit 1 and the SPM is supplied to the surface of the wafer W in the SPM processing unit 1. The resist is removed. Thereafter, the first rinsing process is performed, and pure water is supplied to the surface of the wafer W, so that the SPM adhering to the surface of the wafer W is washed away. Then, after the pure water adhering to the wafer W is once removed by the first spin dry processing, the wafer W is transferred from the SPM processing unit 1 to the rinsing processing unit 2, and in the rinsing processing unit 2, Pure water is again supplied to the surface.

  Even if the sulfuric acid component remains on the surface of the wafer W after the first rinsing process, the remaining sulfuric acid component is dried by the first spin dry process. The dried sulfuric acid component rapidly absorbs moisture, so that the particle size grows at once and becomes easy to peel off from the surface of the wafer W. For this reason, when pure water is supplied to the surface of the wafer W by the rinsing unit 2, the sulfuric acid component remaining on the surface of the wafer W is easily removed. Therefore, even if the pure water adhering to the wafer W is removed again and the wafer W is left standing, there is no possibility that particles to be counted by the particle counter are generated on the surface of the wafer W.

  The flow rate of pure water supplied to the wafer W by the rinse treatment unit 2 is larger than the flow rate of pure water (2 liters per minute) supplied to the wafer W by the SPM processing unit 1 (4 liters per minute). Is set to Since the pure water supplied to the surface of the wafer W has a larger physical energy as the supply flow rate is larger, the sulfuric acid component remaining on the surface of the wafer W is made stronger by supplying the pure water at a higher flow rate. Can be swept away. As a result, the sulfuric acid component remaining on the surface of the wafer W can be eliminated more favorably, and the generation of particles that are counted by the particle counter can be prevented even better.

FIG. 6 is a schematic side view showing another configuration of the rinse treatment unit 2. In FIG. 6, portions corresponding to the above-described portions are denoted by the same reference numerals as those portions. Further, in the following, detailed description of each part given the same reference numeral is omitted.
In the configuration shown in FIG. 6, a two-fluid nozzle 61 for supplying a mixed fluid of pure water and nitrogen gas to the surface of the wafer W is disposed above the spin chuck 41.

  The two-fluid nozzle 61 is connected to a pure water supply pipe 62 to which pure water is supplied and a nitrogen gas supply pipe 63 to which nitrogen gas is supplied. A pure water valve 64 is interposed in the middle of the pure water supply pipe 62. On the other hand, a nitrogen gas valve 65 is interposed in the middle of the nitrogen gas supply pipe 63. When the pure water valve 64 and the nitrogen gas valve 65 are opened, pure water and nitrogen gas flow through the pure water supply pipe 62 and the nitrogen gas supply pipe 63, respectively, and are supplied to the two-fluid nozzle 61. Then, pure water and nitrogen gas are mixed by the two-fluid nozzle 61, and the pure water becomes fine droplets, and these droplets become jets, and the wafer W held on the spin chuck 41 from the two-fluid nozzle 61. Supplied on the surface.

  The two-fluid nozzle 61 is attached to the tip of an arm 66 that extends substantially horizontally above the spin chuck 41. The arm 66 is supported by an arm support shaft 67 extending substantially vertically on the side of the spin chuck 41. Further, a two-fluid nozzle drive mechanism 68 is coupled to the arm support shaft 67, and the control device 60 controls the drive of the two-fluid nozzle drive mechanism 68 to rotate the arm support shaft 67, thereby 66 can be swung.

  In the rinse processing unit 2 having such a configuration, when the wafer W is delivered from the transfer robot TR to the spin chuck 41, the motor 43 is driven and rotation of the wafer W is started. Further, the two-fluid nozzle driving mechanism 68 is driven, and the two-fluid nozzle 61 is disposed above the wafer W held by the spin chuck 41. Then, the pure water valve 64 and the nitrogen gas valve 65 are opened, and a jet of pure water droplets is supplied from the two-fluid nozzle 61 to the surface of the rotating wafer W. On the other hand, the two-fluid nozzle driving mechanism 68 may swing the arm 66 within a predetermined angle range so that the two-fluid nozzle 61 is reciprocated between the rotation center of the wafer W and the peripheral portion. . As a result, the pure water supply position on the surface of the wafer W is reciprocated (scanned) while drawing an arc-shaped trajectory within the range from the rotation center of the wafer W to the peripheral edge of the wafer W. Pure water is supplied evenly throughout the area.

  After the jet of pure water droplets starts to be supplied to the surface of the wafer W, for example, when 60 seconds have elapsed, the pure water valve 64 and the nitrogen gas valve 65 are closed. Then, the two-fluid nozzle 61 is retracted to a position off the upper side of the wafer W. Thereafter, the rotation speed of the wafer W is increased to a predetermined spin dry rotation speed (for example, 2500 rpm), and a second spin dry process for removing pure water from the surface of the wafer W by centrifugal force is performed for, for example, 30 seconds. You can continue. After the second spin dry process, when the motor 43 is stopped and the wafer W is stationary, the wafer W is unloaded from the rinse processing unit 2.

  Since the jet of pure water droplets has a large physical energy, peeling of the sulfuric acid component from the surface of the wafer W can be promoted by supplying the jet to the surface of the wafer W. As a result, the sulfuric acid component remaining on the surface of the wafer W can be eliminated more favorably, and the generation of particles that are counted by the particle counter can be prevented even better.

  As mentioned above, although embodiment of this invention was described, this invention can also be implemented with another form. In the above-described embodiment, the rinse liquid is supplied from the pure water nozzle 26 (or 50) formed on the lower surface of the blocking plate 13 (or 42). However, the nozzle for supplying the rinse liquid is on the spin chuck side. Alternatively, the rinse liquid may be supplied to the wafer W from the nozzle.

  Further, for example, in the rinse treatment unit 2 shown in FIG. 3, an ultrasonic vibrator is provided in association with the blocking plate 42, and ultrasonic vibration is imparted to the pure water supplied from the pure water nozzle 50 to the surface of the wafer W. May be. Further, a nozzle for supplying pure water to the surface of the wafer W may be provided separately from the blocking plate 42. In this case, an ultrasonic vibrator is provided in association with the nozzle, and the nozzle Ultrasonic vibration may be applied to the pure water supplied to the surface of the wafer W.

When the ultrasonic vibration is applied to the pure water, the ultrasonic vibration can promote the separation of the sulfuric acid component from the surface of the wafer W. Therefore, the sulfuric acid component remaining on the surface of the wafer W can be more favorably removed, and the generation of particles that are counted by the particle counter can be further prevented.
Further, in the rinsing processing unit 2 shown in FIG. 6, a blocking plate for controlling the atmosphere near the surface of the wafer W held by the spin chuck 41 is additionally provided. During the second spin dry process, the blocking plate is provided. May be arranged close to the surface of the wafer W held by the spin chuck 41.

Furthermore, in the rinsing unit 2, pure water is supplied to the surface of the wafer W. However, in addition to pure water, an alkaline liquid may be supplied to the surface of the wafer W as a rinsing liquid. Examples of the alkaline liquid include, for example, ammonia hydrogen peroxide (SC1: NH ₄ OH + H ₂ O ₂ + H ₂ O) and cathodic water containing hydroxide ions (liquid generated at the cathode by electrolysis of pure water). can do. When an alkaline liquid is used, the sulfuric acid component remaining on the surface of the wafer W is reacted with the alkaline liquid to produce a salt, and the salt is pushed away with the alkaline liquid, thereby removing the sulfuric acid component from the surface of the wafer W. It can be easily eliminated.

  In the above-described embodiment, the SPM processing unit 1 performs the SPM processing, the first rinsing processing, and the first spin dry processing on the wafer W, and then loads the wafer W into the rinsing processing unit 2 and rinses the wafer W. In the processing unit 2, the second rinsing process and the second spin dry process are performed on the wafer W. After the first spin dry process is performed, the wafer W is not unloaded from the SPM processing unit 1, and the SPM process, A series of processes including the first rinse process, the first spin dry process, the second rinse process, and the second spin dry process may be completed in the SPM processing unit 1. In addition, the SPM processing unit 1 is disposed instead of the rinse processing unit 2, and after the first spin dry process is performed in the SPM processing unit 1, the wafer W is loaded into the SPM processing unit 1 of another chamber, and the wafer W A second rinse process and a second spin dry process may be performed.

Furthermore, although a single wafer type configuration for processing wafers W one by one is taken as an example, the present invention is a batch type configuration for processing a plurality of wafers W at once (for example, an SPM storing SPM). A storage tank, a rinsing liquid storage tank for storing a rinsing liquid, and a drying tank for drying the wafer W, and a structure in which the wafer W is immersed in each tank can also be applied.
The substrate to be processed is not limited to the wafer W, but may be other compound semiconductor wafers, glass substrates for liquid crystal display devices, glass substrates for plasma display panels, glass substrates for photomasks, and magnetic / optical disk substrates. It may be a type of substrate.

  In addition, various design changes can be made within the scope of matters described in the claims.

1 is a schematic plan view showing a layout of a substrate processing apparatus according to an embodiment of the present invention. It is a schematic side view which shows the structure of the SPM process part with which the said substrate processing apparatus is equipped. It is an illustration side view which shows the structure of the rinse process part with which the said substrate processing apparatus is equipped. It is a block diagram which shows the electric constitution of the said substrate processing apparatus. It is process drawing for demonstrating the flow of the process in the said substrate processing apparatus. It is an illustration side view showing other composition of a rinse treating part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Spin chuck 12 SPM nozzle 14 Motor 23 Pure water distribution pipe 24 Pure water supply pipe 25 Pure water valve 26 Pure water nozzle 41 Spin chuck 43 Motor 47 Pure water distribution pipe 48 Pure water supply pipe 49 Pure water valve 50 Pure water nozzle 60 Control device 61 Two-fluid nozzle 62 Pure water supply pipe 63 Nitrogen gas supply pipe 64 Pure water valve 65 Nitrogen gas valve W Wafer

Claims (6)

A treatment liquid supply step for supplying a treatment liquid prepared by mixing sulfuric acid and hydrogen peroxide solution on the surface of the substrate;
A first rinsing liquid supplying step for supplying a rinsing liquid to the surface of the substrate after the treatment liquid supplying step;
A first rinsing liquid removing step for removing the rinsing liquid adhering to the substrate after the first rinsing liquid supplying step;
A second rinsing liquid supply step for supplying the rinsing liquid to the surface of the substrate again after the first rinsing liquid removing step;
A substrate processing method comprising: a second rinsing liquid removing step of removing a rinsing liquid adhering to the substrate after the second rinsing liquid supplying step.   The substrate processing method according to claim 1, wherein the second rinsing liquid supplying step is a step of supplying a rinsing liquid to which ultrasonic vibration is applied to the surface of the substrate.   The substrate processing method according to claim 1, wherein the second rinsing liquid supply step is a step of supplying a mixed fluid of a rinsing liquid and a gas to the surface of the substrate.   The rinsing liquid is supplied to the surface of the substrate at a flow rate larger than the supply flow rate of the rinsing liquid in the first rinsing liquid supply step in the second rinsing liquid supply step. A substrate processing method according to claim 1.   5. The substrate processing method according to claim 1, wherein an alkaline liquid is used as the rinse liquid in the second rinse liquid supply step. Substrate holding means for holding the substrate substantially horizontally;
Substrate rotating means for rotating the substrate held by the substrate holding means;
A treatment liquid supply means for supplying a treatment liquid prepared by mixing sulfuric acid and hydrogen peroxide solution on the surface of the substrate held by the substrate holding means;
Rinsing liquid supply means for supplying a rinsing liquid to the surface of the substrate held by the substrate holding means;
After the processing liquid and the rinsing liquid are supplied to the surface of the substrate in this order, the rinsing liquid attached to the substrate is shaken off by the rotation of the substrate, and the rinsing liquid is supplied again to the surface of the substrate, and then the substrate Substrate processing means comprising: the substrate rotation means, the processing liquid supply means, and a control means for controlling the rinse liquid supply means so that the rinse liquid adhering to the substrate is shaken off by the rotation of the substrate. apparatus.

Images