SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING APPARATUS
The substrate processing method addresses the issue of pattern collapse by using a controlled drying process following phosphoric acid treatment and crude rinsing, ensuring the integrity of refined three-dimensional structures on substrates.
Patent Information
- Application Number
- JP2021083171
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-05-17
- Publication Date
- 2025-03-25
- Estimated Expiration
- 2041-05-17
AI Technical Summary
The challenge is to prevent the collapse of refined three-dimensional structures on substrates during drying, as batch processing can cause these structures to collapse due to dryness.
A substrate processing method involving a phosphoric acid treatment, followed by a crude rinsing step where the phosphoric acid is partially replaced with a rinse solution, and finally a sheet-feature drying step where substrates are dried individually, with temperature control and vapor atmosphere management to minimize pattern collapse.
This method effectively suppresses the collapse of three-dimensional structures by controlling the drying process and maintaining phosphoric acid within the patterns, ensuring high precision and reliability in substrate processing.
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Abstract
Description
[Technical field]
[0001] The present disclosure relates to a substrate processing method and a substrate processing apparatus. [Background technology]
[0002] Conventionally, a batch-type processing apparatus has been proposed that uses phosphoric acid to etch away silicon nitride films. The batch-type processing apparatus processes multiple substrates at once, and therefore can process the substrates with a high throughput. The processing apparatus performs a rinse process in which phosphoric acid adhering to the multiple substrates is replaced with a rinse liquid. The processing apparatus then performs a drying process in which the multiple substrates after the rinse process are dried at once.
[0003] The following Patent Documents 1 and 2 are cited as technologies related to the present application. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Special Publication No. 2016-502275 [Patent Document 2] JP 2020-141063 A Summary of the Invention [Problem to be solved by the invention]
[0005] However, in recent years, three-dimensional structures (eg, patterns) formed on substrates have become more precise, and performing drying treatment on a plurality of substrates at the same time may result in the collapse of the three-dimensional structures.
[0006] Therefore, an object of the present disclosure is to provide a technique that can prevent the collapse of a three-dimensional structure. [Means for solving the problem]
[0007] A first aspect of the substrate processing method includes a phosphoric acid treatment process in which a plurality of substrates are immersed in phosphoric acid in a treatment tank, a rough rinsing process process in which, after the phosphoric acid treatment process, a portion of the phosphoric acid adhering to the plurality of substrates is replaced with a first rinsing liquid to an extent that the phosphoric acid remains in patterns on the plurality of substrates, and a single-wafer drying process process in which, after the rough rinsing process process, the plurality of substrates are dried one by one.
[0008] A second aspect of the substrate processing method is the substrate processing method according to the first aspect, wherein the rough rinsing process is terminated when a concentration of the phosphoric acid in the pattern becomes 50% or more.
[0009] A third aspect of the substrate processing method is the substrate processing method according to the first or second aspect, wherein the rough rinsing process includes a temperature lowering process of lowering a temperature of the first rinsing liquid.
[0010] A fourth aspect of the substrate processing method is a substrate processing method according to any one of the first to third aspects, further comprising a rough drying process step between the rough rinsing process step and the single-wafer drying process step for removing at least a portion of liquid adhering to non-pattern areas of the plurality of substrates where the pattern is not formed.
[0011] A fifth aspect of the substrate processing method is the substrate processing method according to the fourth aspect, wherein in the rough drying process, the plurality of substrates are exposed to an atmosphere of vapor of a second rinsing liquid having a smaller latent heat of vaporization than the first rinsing liquid.
[0012] A sixth aspect of the substrate processing method is a substrate processing method according to any one of the first to fifth aspects, wherein the phosphoric acid treatment step includes a step of lowering the plurality of substrates to immerse them in the phosphoric acid in the treatment tank, and a step of raising the plurality of substrates at a first ascending speed to lift the plurality of substrates from the treatment tank, and the rough rinsing treatment step includes a step of lowering the plurality of substrates to immerse them in the first rinsing liquid, and a step of raising the plurality of substrates at a second ascending speed lower than the first ascending speed to lift the plurality of substrates from the first rinsing liquid.
[0013] A seventh aspect of the substrate processing method is a substrate processing method according to any one of the first to sixth aspects, comprising a first step of transporting the plurality of substrates to a first carrier after the rough rinsing processing step, a second step of transporting the first carrier to a load port of a single-wafer processing apparatus after the first step, a third step of transporting the plurality of substrates one by one from the first carrier of the load port to a single-wafer processing apparatus between the second step and the single-wafer drying processing step, and a fourth step of transporting substrates from the single-wafer processing apparatus to a second carrier of the load port after the single-wafer drying processing step.
[0014] An eighth aspect of the substrate processing method is a substrate processing method according to the seventh aspect, wherein the first carrier includes a water-absorbing member that contacts a portion of an outside pattern area of each of the plurality of substrates where the pattern is not formed.
[0015] A first aspect of the substrate processing apparatus includes a phosphoric acid processing unit having a processing tank and immersing a plurality of substrates in phosphoric acid in the processing tank, a rough rinsing processing unit that replaces a portion of the phosphoric acid adhering to the plurality of substrates with a rinsing liquid to such an extent that the phosphoric acid remains inside the patterns of the plurality of substrates, and a single wafer processing unit that dries the plurality of substrates one by one.
[0016] A second aspect of the substrate processing apparatus is a substrate processing apparatus according to the first aspect, further comprising a posture conversion unit that converts the posture of the plurality of substrates between a horizontal posture and an upright posture, the phosphoric acid processing unit immerses the plurality of substrates in an upright posture in the phosphoric acid in the processing tank, and the single substrate processing unit dries the substrates in a horizontal posture. Effect of the Invention
[0017] According to the first aspect of the substrate processing method and the first and second aspects of the substrate processing apparatus, since phosphoric acid is difficult to evaporate, it is possible to suppress drying of the substrate between the rough rinsing process and the single wafer drying process, and thus it is possible to suppress collapse of the pattern caused by drying.
[0018] According to the second aspect of the substrate processing method, drying of the substrate can be effectively suppressed.
[0019] According to the third aspect of the substrate processing method, since the temperature of the first rinse liquid is initially high, rapid cooling of the substrate can be suppressed, and damage to the substrate caused by rapid cooling can be suppressed. Furthermore, by lowering the temperature of the first rinse liquid, phosphoric acid in the pattern is less likely to be replaced by the first rinse liquid. Therefore, phosphoric acid is more likely to remain in the pattern.
[0020] According to the fourth aspect of the substrate processing method, the amount of liquid adhering to the area outside the pattern on the substrate can be reduced, and therefore, adhesion of the liquid to the substrate transport device can be suppressed.
[0021] According to the fifth aspect of the substrate processing method, the vapor of the second rinsing liquid acts on the region outside the pattern, so that the liquid adhering to the region outside the pattern can be replaced with the second rinsing liquid. Since the second rinsing liquid evaporates easily, the liquid in the region outside the pattern can be effectively removed. Furthermore, since it is difficult to replace phosphoric acid inside the pattern with the second rinsing liquid by the action of the vapor, the phosphoric acid inside the pattern can be left behind. Therefore, collapse of the pattern can be appropriately suppressed.
[0022] According to the sixth aspect of the substrate processing method, since the substrates are raised at the second lower raising speed, the amount of the first rinsing liquid adhering to the non-pattern area of each substrate after the rough rinsing process can be reduced, thereby suppressing the adhesion of the liquid to the substrate transport device.
[0023] According to a seventh aspect of the substrate processing method, since the first carrier stores the substrate after the rough rinsing process, the first carrier may get wet, but the substrate after the single-wafer drying process is stored in a second carrier separate from the first carrier, so that adhesion of liquid to the substrate after the single-wafer drying process can be prevented.
[0024] According to the eighth aspect of the substrate processing method, since the liquid adhering to the non-pattern area is absorbed, it is possible to prevent the liquid from adhering to the transfer device that transfers the substrate. [Brief description of the drawings]
[0025] [Figure 1] 1 is a plan view illustrating an example of a configuration of a substrate processing apparatus according to a first embodiment. [Diagram 2] 1 is a cross-sectional view partially and roughly illustrating an example of a three-dimensional structure of a substrate. [Diagram 3] FIG. 2 is a diagram illustrating an example of the configuration of a rough rinsing processing unit. [Figure 4] FIG. 2 is a diagram illustrating an example of a configuration of a single-wafer processing section. [Diagram 5] 5 is a flowchart showing an example of the operation of the substrate processing apparatus according to the first embodiment. [Figure 6] 1 is a graph showing a vapor pressure curve. [Figure 7] 10 is a flowchart showing a specific example of a rough rinsing process. [Figure 8] FIG. 11 is a diagram illustrating an example of the configuration of a rough rinsing processor according to a second embodiment. [Figure 9] FIG. 11 is a diagram illustrating an example of the configuration of a rough rinsing processor according to a second embodiment. [Figure 10] 13 is a flowchart showing an example of the operation of the substrate processing apparatus according to the third embodiment. [Figure 11] FIG. 2 is a front view illustrating an example of a configuration of a carrier. [Figure 12] FIG. 2 is an enlarged view illustrating an example of a portion of a configuration of a carrier. [Figure 13] FIG. 13 is an enlarged view illustrating an example of a part of another configuration of the carrier. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Hereinafter, an embodiment will be described with reference to the accompanying drawings. Note that the components described in the embodiment are merely examples, and are not intended to limit the scope of the present disclosure. In the drawings, the dimensions or numbers of each part may be exaggerated or simplified as necessary for ease of understanding.
[0027] Expressions indicating relative or absolute positional relationships (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.) not only strictly indicate the positional relationship, but also indicate a state in which the two are relatively displaced in terms of angle or distance within a range in which a tolerance or similar function is obtained, unless otherwise specified. Expressions indicating an equal state (e.g., "same," "equal," "homogeneous," etc.) not only strictly indicate a state in which the two are quantitatively equal, but also indicate a state in which there is a difference in which a tolerance or similar function is obtained, unless otherwise specified. Expressions indicating a shape (e.g., "square shape" or "cylindrical shape," etc.) not only strictly indicate the shape geometrically, but also indicate a shape having, for example, unevenness or chamfering, within a range in which a similar effect is obtained, unless otherwise specified. The expressions "comprise," "include," "have," "includes," "includes," or "has" a component are not exclusive expressions that exclude the presence of other components. The expression "at least one of A, B, and C" includes A only, B only, C only, any two of A, B, and C, and all of A, B, and C.
[0028] <First embodiment> <Overall configuration of substrate processing apparatus> 1 is a plan view illustrating an example of a configuration of a substrate processing apparatus 10. The substrate processing apparatus 10 is an apparatus for performing wet processing on a substrate W.
[0029] The substrate W is, for example, a semiconductor substrate, and a three-dimensional structure (hereinafter, referred to as a pattern) is formed on the main surface of the substrate W. As a more specific example, a three-dimensional structure in the middle of manufacturing a three-dimensional NAND (Not-AND) flash memory is formed on the main surface of the substrate W. FIG. 2 is a cross-sectional view partially and roughly showing an example of the three-dimensional structure of the substrate W. In the example of FIG. 2, the substrate W includes a support layer 93. The support layer 93 is, for example, a silicon layer. A laminated structure 90 is formed on the support layer 93. The laminated structure 90 includes a plurality of insulating films 91 and a plurality of sacrificial films 92. The insulating films 91 and the sacrificial films 92 are alternately laminated in the Z-axis direction. The insulating film 91 is, for example, a silicon dioxide film, and the sacrificial film 92 is, for example, a silicon nitride film. The insulating films 91 and the sacrificial films 92 have thicknesses of, for example, 1 nm or more and 50 nm or less. In addition, a trench 94 is formed in the laminated structure 90. The trench 94 penetrates the laminated structure 90 along the thickness direction of the substrate W. In addition, a pillar (not shown) is provided in the laminated structure 90. The pillars support the insulating film 91 when the sacrificial film 92 is removed. The width of the pillars (the width parallel to the main surface of the substrate W) is, for example, not less than 1 nm and not more than 50 nm.
[0030] In the present embodiment, a case where the substrate processing apparatus 10 etches the sacrificial film 92 will be described as a specific example, but the substrate processing apparatus 10 may perform other processes on the substrate W.
[0031] As shown in FIG. 1, a substrate processing apparatus 10 includes a batch-type first processing apparatus 20, a single-wafer-type second processing apparatus 50, and an inter-apparatus transfer section .
[0032] The first processing apparatus 20 includes a load port 21, a transport section 22, a phosphoric acid processing section 30, and a rough rinsing processing section 40. The load port 21 is an input / output port for transferring a plurality of substrates W to and from the outside. The plurality of substrates W are loaded into the load port 21 while being stored in a portable container (hereinafter referred to as a carrier) C1. In the carrier C1, the plurality of substrates W are stored, for example, in a horizontal position and aligned vertically. The horizontal position here means a position in which the thickness direction of the substrate W is aligned vertically. Here, the substrates W are stored in the carrier C1 with their surfaces facing vertically upward. The number of substrates W stored in the carrier C1 is not particularly limited, but is, for example, 25.
[0033] The carrier C1 may be a front opening unified pod (FOUP) that stores the substrate W in an enclosed space, a standard mechanical interface (SMIF) pod, or an open cassette (OC) that exposes the substrate W to the outside air.
[0034] In the example of Fig. 1, carrier C2 (corresponding to the first carrier) is also loaded into the load port 21. In the load port 21, carrier C1 and carrier C2 are arranged side by side in a horizontal first arrangement direction. Carrier C2 has a similar configuration to carrier C1. However, as described later, carrier C2 is used to transport multiple substrates W between the first processing apparatus 20 and the second processing apparatus 50.
[0035] In the example of FIG. 1, the first processing apparatus 20 includes a housing 29, in which at least a transfer section 22, a phosphoric acid processing section 30, and a rough rinsing processing section 40 are provided.
[0036] The transfer section 22 transfers a plurality of substrates W between the load port 21, the phosphoric acid treating section 30, and the rough rinsing treating section 40. In the example of FIG.
[0037] The transport robot 23 is provided so as to be movable along the first arrangement direction of the carriers C1 and C2 by a moving mechanism 232. The transport robot 23 can be stopped at a position facing each of the carriers C1 and C2. The moving mechanism 232 includes a mechanism such as a ball screw mechanism including a motor.
[0038] The transport robot 23 takes out a plurality of unprocessed substrates W from the carrier C1 of the load port 21, and transfers the plurality of substrates W to the attitude conversion unit 24. For example, the transport robot 23 includes a plurality of hands 231 and a hand moving mechanism (not shown). The hand moving mechanism has, for example, an arm mechanism including a motor, a lifting mechanism, and a rotating mechanism, and moves the hand 231 in the horizontal and vertical directions. The transport robot 23 takes out the plurality of substrates W from the carrier C1 by moving the plurality of hands 231 to a position facing the carrier C1. As a result, one substrate W is placed on each hand 231. Then, the transport robot 23 transfers the plurality of substrates W to the attitude conversion unit 24 by moving the hands 231 holding the substrates W.
[0039] The posture conversion unit 24 converts the posture of the multiple substrates W from a horizontal posture to an upright posture. The upright posture here means a posture in which the thickness direction of the substrate W is along the horizontal direction. The posture conversion unit 24 includes a holding member 241, a rotating member 242, and a rotation mechanism (not shown). The rotating member 242 is provided so as to be rotatable around a predetermined rotation axis Q2. The rotation axis Q2 is an axis extending along the horizontal direction. The holding member 241 is attached to the rotating member 242, and holds the multiple substrates W. The rotation mechanism includes a motor, and rotates the rotating member 242 90 degrees around the rotation axis Q2 between an upright rotation position and a horizontal rotation position. As a result, the posture of the multiple substrates W held by the holding member 241 is converted between the horizontal posture and the upright posture.
[0040] The holding member 241 has an elongated shape that is long in a predetermined longitudinal direction, and when the rotating member 242 is located at a horizontal rotation position, the longitudinal direction of the holding member 241 is aligned along the vertical direction. In the example of FIG. 1, four holding members 241 are provided. A plurality of grooves (not shown) are formed in the holding member 241 in a row in the longitudinal direction. The pitch of the grooves is equal to the pitch of the plurality of substrates W. The end of the substrate W is inserted into each groove of each holding member 241, whereby the holding member 241 supports each substrate W at four points. In the example of FIG. 1, the posture conversion unit 24 that holds the plurality of substrates W in a horizontal posture is indicated by a solid line.
[0041] When the rotating member 242 rotates from the horizontal rotation position to the upright rotation position, the longitudinal direction of the holding member 241 is aligned horizontally, and the posture of the substrates W is converted from the horizontal posture to the upright posture. In the example of Fig. 1, the posture conversion unit 24 that holds multiple substrates W in the upright posture is indicated by a two-dot chain line.
[0042] The transport robot 25 receives the substrates W from the attitude changing unit 24 and transports the substrates W to the phosphoric acid processing unit 30. In the example of FIG. 1, the transport robot 25 includes a pair of holding members 251, a base 252, and an opening / closing mechanism 253. The holding members 251 are displaceably attached to the base 252. The opening / closing mechanism 253 moves the holding members 251 between an open position and a closed position. The closed position is a position where the distance between the two holding members 251 is narrow, and the holding members 251 hold the substrates W. The open position is a position where the distance between the two holding members 251 is wide, and the holding members 251 release the holding of the substrates W. The opening / closing mechanism 253 includes, for example, a motor. The transport robot 25 is provided so as to be movable along a horizontal transport direction by a moving mechanism 254. Specifically, the moving mechanism 254 moves the base 252 along the transport direction. As a result, the holding member 251, the base 252, and the opening / closing mechanism 253 move together in the conveying direction. The moving mechanism 254 includes a mechanism such as a ball screw mechanism including a motor.
[0043] The phosphoric acid treating apparatus 30 is a batch-type treating apparatus which performs phosphoric acid treatment on a plurality of substrates W collectively. In the example of FIG. 1, the phosphoric acid treating apparatus 30 includes a treatment tank 31 and a lifter 32. The treatment tank 31 stores phosphoric acid. The lifter 32 raises and lowers the plurality of substrates W between a transfer position and a treatment position. The transfer position is a position vertically above the upper end of the treatment tank 31, where the plurality of substrates W are transferred between the lifter 32 and the transport robot 25. The treatment position is a position where the plurality of substrates W are immersed in phosphoric acid in the treatment tank 31.
[0044] The lifter 32 lowers the multiple substrates W to the processing position, so that the multiple substrates W are immersed in the phosphoric acid in the processing tank 31. This causes the phosphoric acid to act on the sacrificial film 92 through the trenches 94 of each substrate W, and etches and removes the sacrificial film 92. When the sacrificial film 92 is removed, the insulating film 91 is no longer supported by the sacrificial film 92, and therefore becomes more likely to collapse.
[0045] The transfer robot 25 receives the plurality of substrates W after the phosphoric acid treatment from the phosphoric acid treating unit 30, and transports the plurality of substrates W to the rough rinsing unit 40. In the example of FIG. 1, the rough rinsing unit 40 is provided at a position adjacent to the phosphoric acid treating unit 30 in the transport direction of the transfer robot 25.
[0046] The rough rinsing processor 40 performs a rough rinsing process on the substrates W that have been phosphoric acid treated by the phosphoric acid processor 30. The rough rinsing process is a process for replacing a part of the phosphoric acid attached to the substrates W with a first rinsing liquid to such an extent that phosphoric acid remains within the patterns of the substrates W (e.g., within the trenches 94 and between the insulating films 91). The first rinsing liquid is, for example, pure water.
[0047] 3 is a diagram illustrating an example of the configuration of the rough rinsing processor 40. In the example of FIG. 3, the rough rinsing processor 40 includes a processing tank 41, a lifter 42, a rinsing liquid supply unit 43, a discharge unit 44, and a chamber 49.
[0048] The processing tank 41 has a box shape that opens vertically upward, and stores a rinsing liquid. The processing tank 41 is provided in a chamber 49. An openable and closable lid (which may also be called a shutter) is provided at the top of the chamber 49. With the lid of the chamber 49 open, a plurality of substrates W are carried into the chamber 49 through the top opening, or are carried out from the inside of the chamber 49 through the top opening.
[0049] The lifter 42 raises and lowers the substrates W. In the example of FIG. 3, the lifter 42 includes a plurality of holding members 421 (three in the figure) that hold the substrates W in an upright position, a base 422 that supports the holding members 421, and a lifting mechanism 423 that raises and lowers the base 422. Each holding member 421 has an elongated shape that extends along the thickness direction of the substrate W (the direction perpendicular to the paper surface in FIG. 3), and its base end is attached to the base 422. Each holding member 421 has a plurality of grooves (not shown) formed side by side in its longitudinal direction. The pitch of the grooves is equal to the pitch of the substrates W. The ends of the substrates W are inserted into the grooves of the holding members 421, so that the holding members 421 hold the substrates W in an upright position. The base 422 has a plate-like shape and is provided with its thickness direction aligned with the longitudinal direction of the holding members 421. The lifting mechanism 423 lifts and lowers the base 422, thereby lifting and lowering the multiple substrates W held by the holding member 421. The lifting mechanism 423 includes, for example, a ball screw mechanism including a motor, a cam mechanism, or a mechanism such as an air cylinder. In the following, the main body of lifting and lowering by the lifting mechanism 423 may be described as a lifter 42.
[0050] The lifter 42 raises and lowers the multiple substrates W between a transfer position vertically above the processing tank 41 and a processing position within the processing tank 41. In the example of Fig. 3, the transfer position is a position vertically above the chamber 49, where the multiple substrates are transferred between the lifter 42 and the transport section 22. In the example of Fig. 3, the lifter 42 positioned at the transfer position is indicated by a two-dot chain line. The processing position is a position where the multiple substrates W are immersed in a processing liquid.
[0051] The rinsing liquid supply unit 43 supplies a first rinsing liquid to the processing tank 41. In the example of Fig. 3, the rinsing liquid supply unit 43 includes a nozzle 431, a liquid supply pipe 432, and a valve 433. In the example of Fig. 3, the nozzle 431 is provided at a lower part in the processing tank 41. The downstream end of the liquid supply pipe 432 is connected to the nozzle 431, and the upstream end of the liquid supply pipe 432 is connected to a rinsing liquid supply source. The rinsing liquid supply source has a tank (not shown) that stores the first rinsing liquid.
[0052] The valve 433 is disposed in the liquid supply pipe 432. When the valve 433 is opened, the first rinse liquid is supplied from a rinse liquid supply source through the liquid supply pipe 432 to the nozzle 431, and the first rinse liquid is discharged from the discharge port of the nozzle 431 into the processing tank 41. When the valve 433 is closed, the supply of the first rinse liquid to the processing tank 41 is terminated.
[0053] 3, a heater 434 is provided in the liquid supply pipe 432. The heater 434 heats the first rinse liquid. As a result, the heated first rinse liquid is supplied to the processing bath 41.
[0054] 3, the rough rinsing processing unit 40 is provided with an upflow tank 411. The upflow tank 411 is an outer tank that receives the first rinsing liquid that has overflowed from the upper end of the processing tank 41.
[0055] The drain unit 44 drains the first rinsing liquid from the processing tank 41 and the upflow tank 411. The drain unit 44 includes a drain pipe 441, a drain pipe 442, a valve 443, and a valve 444. An upstream end of the drain pipe 441 is connected to, for example, the bottom of the processing tank 41, and an upstream end of the drain pipe 442 is connected to, for example, the bottom of the upflow tank 411.
[0056] Valves 443 and 444 are respectively interposed in drain pipes 441 and 442. When valve 443 is opened, the first rinse liquid in processing tank 41 is discharged to the outside through drain pipe 441, and when valve 443 is closed, the discharge of the first rinse liquid in processing tank 41 is completed. When valve 444 is opened, the first rinse liquid in upflow tank 411 is discharged to the outside through drain pipe 442, and when valve 444 is closed, the discharge of the first rinse liquid in upflow tank 411 is completed.
[0057] The lifter 42 of the rough rinsing processing unit 40 can perform a rough rinsing process by immersing the plurality of substrates W after the phosphoric acid process in the first rinsing liquid in the processing bath 41 for a short period of time.
[0058] Furthermore, during the rough rinsing process, the valves 433 and 444 may be opened. In this way, the first rinsing liquid supplied into the processing tank 41 by the rinsing liquid supply unit 43 flows vertically upward in the processing tank 41. Then, the first rinsing liquid overflows from the upper part of the processing tank 41 and is discharged to the outside through the upflow tank 411 and the drain pipe 441. In this way, a liquid flow (so-called upflow) flowing vertically upward is formed in the processing tank 41. Therefore, adhesion of impurities to the substrate W can be suppressed.
[0059] The transfer robot 25 receives the multiple substrates W after the rough rinsing process from the rough rinsing processor 40, and transfers the multiple substrates W to the attitude changing unit 24. The attitude changing unit 24 changes the attitude of the substrates W from an upright attitude to a horizontal attitude. The transfer robot 23 receives the multiple substrates W in the horizontal attitude from the attitude changing unit 24, and transfers the multiple substrates W to the carrier C2 of the load port 21.
[0060] The inter-apparatus transfer section 70 takes out the carrier C2 after the rough rinsing process from the load port 21 of the first processing apparatus 20, and transfers the carrier C2 to the second processing apparatus 50. The inter-apparatus transfer section 70 includes a carrier holding section and a moving mechanism, both of which are not shown. The carrier holding section is a member that holds the carrier C2. A held member held by the carrier holding section is provided, for example, on the upper portion of the carrier C2, and the carrier holding section grips the non-held member. The moving mechanism includes, for example, a motor, and moves the carrier holding section between the first processing apparatus 20 and the second processing apparatus 50.
[0061] The second processing apparatus 50 includes a load port 51, an indexer robot 52, a transport robot 53, and a single wafer processing apparatus 60. The load port 51 is an input / output port for transferring a plurality of substrates W to and from the outside. The plurality of substrates W are stored in a carrier C2 and are transported to the load port 51 by an inter-apparatus transport section 70. In the example of FIG. 1, a carrier C3 (corresponding to a second carrier) is also transported to the load port 51. In the load port 51, the carriers C2 and C3 are arranged in a horizontal second arrangement direction. The carrier C3 has a similar configuration to the carriers C1 and C2. However, the carrier C3 is used to transport a plurality of substrates W from the second processing apparatus 50 to a downstream apparatus (not shown).
[0062] 1, the second processing apparatus 50 includes a housing 59. Inside the housing 59, at least an indexer robot 52, a transfer robot 53, and a single wafer processing apparatus 60 are provided.
[0063] The indexer robot 52 is provided so as to be movable along the second arrangement direction by a moving mechanism 522, and can be stopped at a position facing each of the carriers C2 and C3. The indexer robot 52 includes a hand 521 and a hand moving mechanism (not shown). The indexer robot 52 moves the hand 521 to transport the substrate W between the load port 51 and the transport robot 53.
[0064] The transport robot 53 transports the substrate W between the indexer robot 52 and the single wafer processing unit 60. In the example of Fig. 1, a plurality of single wafer processing units 60 are provided around the transport robot 53. Specifically, four single wafer processing units 60 are provided to surround the transport robot 53. The transport robot 53 includes a hand 531 and a hand moving mechanism 532. The transport robot 53 transports the substrate W between the indexer robot 52 and the single wafer processing unit 60 by moving the hand 531.
[0065] Each single wafer processing unit 60 dries at least one substrate W at a time. The drying process is not particularly limited, and may be, for example, spin drying. FIG. 4 is a diagram showing an example of the configuration of the single wafer processing unit 60. The single wafer processing unit 60 includes a substrate holding unit 61. The substrate holding unit 61 holds the substrate W in a horizontal position. In the example of FIG. 4, the substrate holding unit 61 includes a stage 611 and a plurality of chuck pins 612. The stage 611 has a disk shape and is provided vertically below the substrate W. The stage 611 is provided with its thickness direction aligned with the vertical direction.
[0066] The multiple chuck pins 612 are erected on the upper surface of the stage 611. Each of the multiple chuck pins 612 is provided so as to be displaceable between a chuck position in contact with the peripheral edge of the substrate W and a release position away from the peripheral edge of the substrate W. When the multiple chuck pins 612 move to their respective chuck positions, the multiple chuck pins 612 hold the substrate W. When the multiple chuck pins 612 move to their respective release positions, the hold of the substrate W is released.
[0067] In the example of FIG. 4, the substrate holder 61 further includes a rotation mechanism 613, which rotates the substrate W around a rotation axis Q1. The rotation axis Q1 is an axis that passes through the center of the substrate W and is along the Z-axis direction. For example, the rotation mechanism 613 includes a shaft 614 and a motor 616. The upper end of the shaft 614 is connected to the lower surface of the stage 611 and extends from the lower surface of the stage 611 along the rotation axis Q1. The motor 616 rotates the shaft 614 around the rotation axis Q1 to rotate the stage 611 and the multiple chuck pins 612 together. As a result, the substrate W held by the multiple chuck pins 612 rotates around the rotation axis Q1. Such a substrate holder 61 may be called a spin chuck.
[0068] The substrate holder 61 rotates the substrate W at high speed around the rotation axis Q1, thereby scattering liquid adhering to the substrate W from the periphery of the substrate W, thereby drying the substrate W (so-called spin drying).
[0069] 4, the single wafer processing unit 60 also includes a guard 62. The guard 62 has a cylindrical shape and surrounds the substrate W held by the substrate holding unit 61. The guard 62 receives liquid splashed from the periphery of the substrate W.
[0070] In the example of FIG. 4, the single wafer processing unit 60 also includes a nozzle 63. The nozzle 63 is used to supply a cleaning liquid and a rinsing liquid to the substrate W as a pre-processing before the drying process. The cleaning liquid includes, for example, SC-1 (ammonia-hydrogen peroxide mixture). The rinsing liquid includes, for example, at least one of pure water and isopropyl alcohol. The nozzle 63 is provided so as to be movable between a nozzle processing position and a nozzle standby position by a moving mechanism 64. The nozzle processing position is, for example, a position facing the center of the surface of the substrate W in the Z-axis direction, and the nozzle standby position is, for example, a position radially outward from the substrate W. The moving mechanism 64 has, for example, a mechanism such as a ball screw mechanism or an arm rotation mechanism. When the nozzle 63 is located at the nozzle processing position, the rinsing liquid is discharged onto the rotating substrate W. As a result, the cleaning liquid or rinsing liquid that has landed on the surface of the substrate W is subjected to centrifugal force and spreads over the entire surface of the substrate W, and is scattered outward from the periphery of the substrate W. As a result, the cleaning process and the rinsing process can be performed on the substrate W.
[0071] <An example of the operation of the substrate processing apparatus> 5 is a flow chart that outlines an example of a processing step for a substrate W. First, a carrier C1 that stores a plurality of unprocessed substrates W is loaded into the load port 21 of the first processing apparatus 20 by a transfer apparatus (not shown) (step S11: wafer loading step).
[0072] Next, the transfer unit 22 takes out the multiple substrates W from the carrier C1, converts the attitude of the substrates W from the horizontal attitude to an upright attitude, and transfers the multiple substrates W in the upright attitude to the phosphoric acid treating unit 30 (step S12: first batch transfer step). As a result, the multiple substrates W are handed over to the lifter 32 of the phosphoric acid treating unit 30.
[0073] Next, the phosphoric acid treatment unit 30 performs phosphoric acid treatment on the multiple substrates W collectively (step S13: phosphoric acid treatment step). Specifically, the lifter 32 lowers the multiple substrates W to the treatment position. As a result, the multiple substrates W are immersed in the phosphoric acid in the treatment tank 31. The concentration of the phosphoric acid is, for example, 80% or more, and as a more specific example, about 86%. Here, the temperature of the phosphoric acid is maintained at, for example, about 160 degrees. For example, a circulation pipe may be provided in the treatment tank 31, and a heater may be provided in the circulation pipe. The heater may heat the phosphoric acid flowing through the circulation pipe, thereby adjusting the temperature of the phosphoric acid in the treatment tank 31.
[0074] When the plurality of substrates W are immersed in the phosphoric acid in the processing tank 31, the phosphoric acid acts on the sacrificial film 92 through the trenches 94, and the sacrificial film 92 is etched away.
[0075] When the sacrificial film 92 has been sufficiently removed, the lifter 32 raises the substrates W to the delivery position, and lifts the substrates W out of the processing bath 31 .
[0076] Next, the transport unit 22 receives the plurality of substrates W after the phosphoric acid treatment from the lifter 32 of the phosphoric acid treating unit 30, and transports the plurality of substrates W to the rough rinsing processing unit 40 (step S14: second batch transport step). As a result, the plurality of substrates W are handed over to the lifter 42 of the rough rinsing processing unit 40.
[0077] Next, the rough rinsing processor 40 performs rough rinsing processing collectively on the plurality of substrates W (step S15: rough rinsing processing step). Specifically, first, the lifter 42 lowers the plurality of substrates W in an upright posture to the processing position. As a result, the plurality of substrates W are immersed in the first rinsing liquid in the processing bath 41.
[0078] As a result, phosphoric acid attached to the plurality of substrates W is gradually replaced with the first rinse liquid over time. More specifically, phosphoric acid inside the pattern of the substrate W (here, inside the trenches 94 and between the insulating films 91) gradually flows outward from the openings 941, and instead, the first rinse liquid enters the inside of the pattern. Thus, phosphoric acid inside the pattern is replaced with the first rinse liquid relatively slowly.
[0079] On the other hand, in the non-patterned area of each substrate W, the phosphoric acid is replaced with the first rinse liquid relatively quickly because the non-patterned area is flat. The non-patterned area includes the peripheral area of the front surface of the substrate W where no pattern is formed, and the back surface of the substrate W.
[0080] This rough rinsing process is completed when phosphoric acid remains inside the pattern. For example, the lifter 32 raises the substrates W to the transfer position with phosphoric acid remaining inside the pattern, and lifts the substrates W from the first rinsing liquid. This substantially completes the rough rinsing process. More specifically, the lifter 32 lifts the substrates W from the first rinsing liquid when a specified processing time has elapsed since the substrates W were immersed in the first rinsing liquid. The processing time is measured, for example, by a timer circuit (not shown). The processing time is set in advance to a time that allows phosphoric acid to remain sufficiently inside the pattern of the substrate W. The processing time that allows phosphoric acid to remain sufficiently inside the pattern means, for example, a state in which the concentration of phosphoric acid inside the pattern (for example, a mass concentration of 50% or more. In other words, the concentration of phosphoric acid in the pattern) is set in advance so that it does not fall below 50%. This processing time is set, for example, by simulation or experiment, and is set to about 2 to 5 minutes as a specific example.
[0081] As described above, a low concentration of phosphoric acid remains inside the pattern on the substrate W by the rough rinsing process.
[0082] As described above, the phosphoric acid treating section 30 immerses the plurality of substrates W in high-temperature phosphoric acid, so that the substrates W are at a high temperature after the phosphoric acid treating process. If the high-temperature substrates W are immersed in the low-temperature first rinse solution, the substrates W may be damaged due to rapid cooling.
[0083] Therefore, the rough rinsing processing unit 40 may adjust the temperature of the first rinsing liquid in the processing tank 41 to a temperature higher than room temperature and lower than the temperature of phosphoric acid in the phosphoric acid treatment, for example, to about 60° C. For example, a heater 434 may heat the first rinsing liquid flowing through the liquid supply pipe 432, and supply the heated first rinsing liquid into the processing tank 41. By controlling the heating of the heater 424, the temperature of the first rinsing liquid in the processing tank 41 can be adjusted.
[0084] According to this, since the temperature of the first rinsing liquid is higher than room temperature (for example, 25° C.), rapid cooling of the substrate W can be suppressed, and damage to the substrate W can be reduced.
[0085] Furthermore, in this rough rinsing process, the valves 433 and 444 may be opened. This causes the first rinsing liquid supplied from the nozzle 431 into the processing tank 41 to flow vertically upward in the processing tank 41, overflow from the upper part of the processing tank 41, be received in the upflow tank 411, and be discharged to the outside through the drain pipe 442. This forms a liquid flow (so-called upflow) that flows vertically from the lower side to the upper side in the processing tank 41. This makes it possible to prevent impurities in the first rinsing liquid from adhering to the substrate W.
[0086] Next, the transfer unit 22 receives the substrates W from the lifter 42 of the rough rinsing processing unit 40, converts the attitude of the substrates W from an upright attitude to a horizontal attitude, and transfers the substrates W in the horizontal attitude to the carrier C2 of the load port 21 (step S16: third batch transfer step: corresponding to the first step). Here, the substrates W are stored in the carrier C2 with their surfaces facing vertically upward.
[0087] Next, the inter-apparatus transfer section 70 takes out the carrier C2 from the load port 21 of the first processing apparatus 20, and transfers the carrier C2 to the load port 51 of the second processing apparatus 50 (step S20: inter-apparatus transfer step: corresponding to the second step).
[0088] Next, the indexer robot 52 and the transport robot 53 sequentially transport the substrate W from the carrier C2 of the load port 51 to each single wafer processing unit 60 (step S21: first single wafer transport step: corresponding to the third step). As a result, the substrate holder 61 of each single wafer processing unit 60 holds the substrate W in a horizontal position.
[0089] Next, the single wafer processing unit 60 performs cleaning and rinsing processing on the substrate W (step S22: cleaning and rinsing processing step). Specifically, the substrate holder 61 rotates the substrate W around the rotation axis Q1, and the moving mechanism 64 moves the nozzle 63 to the nozzle processing position. Then, the nozzle 63 ejects a first rinsing liquid (e.g., pure water) onto the upper surface of the substrate W while rotating. The first rinsing liquid that has landed on the upper surface of the substrate W receives centrifugal force accompanying the rotation of the substrate W, spreads over the upper surface of the substrate W, and scatters outward from the periphery of the substrate W. This allows the phosphoric acid remaining on the substrate W to be replaced with the first rinsing liquid. Next, the single wafer processing unit 60 may eject the cleaning liquid and the first rinsing liquid from the nozzle 63 in this order toward the substrate W, as necessary. Alternatively, the nozzle 63 may eject a second rinsing liquid (e.g., isopropyl alcohol) having a smaller latent heat of vaporization than the first rinsing liquid toward the substrate W.
[0090] Next, the single wafer processing unit 60 performs a drying process on the substrate W (step S23: single wafer drying process step). Specifically, the substrate holding unit 61 increases the rotation speed of the substrate W (so-called spin drying). This causes the substrate W to be dried. When the substrate W is sufficiently dried, the substrate holding unit 61 stops rotating the substrate W.
[0091] Next, the transfer robot 53 and the indexer robot 52 transfer the substrate W from the single wafer processing section 60 to the carrier C3 of the load port 51 (step S24: second single wafer transfer step: corresponding to the fourth step).
[0092] When the number of substrates W in the carrier C3 reaches a predetermined number (25 in this example), a transport device (not shown) removes the carrier C3 from the load port 51 and transports the carrier C3 to a processing device further downstream.
[0093] As described above, according to the substrate processing apparatus 10, the batch-type phosphoric acid processor 30 can collectively perform phosphoric acid processing on a plurality of substrates W (step S13). This allows the sacrificial films 92 of the plurality of substrates W to be etched away with high throughput. In particular, since removal of the sacrificial film 92 with phosphoric acid takes time, the batch-type processing in which a plurality of substrates W is processed collectively is advantageous.
[0094] Moreover, after the phosphoric acid treatment, a rough rinsing process is performed (step S15). Therefore, a low concentration of phosphoric acid is contained inside the pattern of the substrate W after the rough rinsing process. Since this phosphoric acid does not evaporate easily, drying of each substrate W can be suppressed in the period between the rough rinsing process (step S15) and the single-wafer processing (step S22). Therefore, collapse of the pattern of the substrate W due to drying (for example, collapse of the insulating film 91) can be suppressed or avoided.
[0095] FIG. 6 is a graph showing a vapor pressure curve of phosphoric acid. FIG. 6 shows the vapor pressure curves in graphs G1 to G5 according to temperature. Graphs G1 to G5 show the vapor pressure at temperatures of 25° C., 40° C., 60° C., 80° C., and 100° C., respectively. As can be seen from FIG. 6, the vapor pressure of phosphoric acid is lower than that of pure water (i.e., phosphoric acid with a concentration of 0%). In particular, when the concentration of phosphoric acid is 50% or more, the vapor pressure drops more rapidly with increasing concentration. In other words, when the concentration of phosphoric acid is 50% or more, phosphoric acid is significantly less likely to evaporate than when the concentration of phosphoric acid is less than 50%. Therefore, by setting the processing time of the rough rinsing process to a degree that the concentration of phosphoric acid in the pattern after the rough rinsing process is 50% or more, the drying of the substrate W after the rough rinsing process can be more appropriately suppressed.
[0096] The rough rinsing process (step S15) may be terminated when the concentration of phosphoric acid in the pattern is, for example, 60% or more, or 70% or more.
[0097] Furthermore, the substrates W after the rough rinsing process are dried one by one by the single wafer processing unit 60 (step S23). In the single wafer drying process, the substrates W are dried one by one, so that the substrates W can be dried with high drying performance. Therefore, the collapse of the pattern on the substrate W caused by the drying process can be suppressed or avoided.
[0098] Furthermore, the rough rinsing process can replace most or all of the phosphoric acid attached to the out-of-pattern region of the substrate W with the first rinsing liquid. This is because the out-of-pattern region is flatter than the region where the pattern is provided, and therefore the phosphoric acid in the out-of-pattern region is easily replaced with the first rinsing liquid even in the rough rinsing process. Therefore, in the rough rinsing process, most of the phosphoric acid in the out-of-pattern region can be replaced with the first rinsing liquid.
[0099] Incidentally, as described above, the substrate W after the rough rinsing process is successively held by the transport unit 22, the carrier C2, the indexer robot 52, and the transport robot 53. These hold a plurality of substrates W in contact with the non-patterned regions (e.g., the back surface of the substrate W). Since most or all of the phosphoric acid in the non-patterned regions can be replaced with the first rinsing liquid by the rough rinsing process, adhesion of phosphoric acid to these can be suppressed or avoided.
[0100] In the above example, the carrier C2 is loaded into the second processing apparatus 50. That is, the wet substrate W after the rough rinsing process is transported by the carrier C2. Therefore, liquid may adhere to the carrier C2 as well. Then, the substrate W that has been dried by the single wafer processing apparatus 60 is transported by the transport robot 53 and the indexer robot 52 to a carrier C3 different from the carrier C2. This makes it possible to prevent re-adhesion of liquid to the substrate W, which occurs when the dried substrate W is stored in the carrier C2.
[0101] <Transportation of Carrier C2> When the indexer robot 52 has removed all of the substrates W from the carrier C2, the inter-apparatus transport section 70 may remove the empty carrier C2 from the load port 51 and transport the carrier C2 to the load port 21 of the first processing apparatus 20. This allows the carrier C2 to be used again to transport a plurality of substrates W from the first processing apparatus 20 to the second processing apparatus 50. Although the inside of the carrier C2 may become wet from the previous transport of substrates W, no problem occurs because the plurality of substrates W processed by the first processing apparatus 20 are wet.
[0102] <Hand> The indexer robot 52 may include a plurality of hands 521. In this case, the indexer robot 52 may include a hand 521 for the outward path and a hand 521 for the return path. That is, the indexer robot 52 may transport the substrate W from the carrier C2 to the transport robot 53 with the hand 521 for the outward path, and transport the substrate W from the transport robot 53 to the carrier C3 with the hand 521 for the return path. With this, even if liquid from the substrate W adheres to the hand 521 for the outward path, it is possible to suppress or avoid the liquid from adhering to the substrate W that has been dried via the hand 521. The transport robot 53 may also include a hand 531 for the outward path and a hand 531 for the return path.
[0103] <Rough rinsing process (lowering the temperature of the first rinse solution)> Next, an example of temperature control in the rough rinsing process will be described. In the above example, the temperature of the first rinsing liquid in the rough rinsing process is set to a value (for example, about 60° C.) higher than room temperature and lower than the temperature of phosphoric acid in the phosphoric acid process. This prevents rapid cooling of the high-temperature substrate W after the phosphoric acid process, and prevents damage to the substrate W. However, the higher the temperature of the first rinsing liquid, the more quickly the phosphoric acid is replaced by the first rinsing liquid. Moreover, an excessive decrease in the concentration of phosphoric acid inside the pattern is undesirable in terms of preventing drying of the substrate W after the rough rinsing process.
[0104] Therefore, the substrate processing apparatus 10 may lower the temperature of the first rinsing liquid in the rough rinsing process, as described below.
[0105] 7 is a flow chart showing a specific example of the rough rinsing process. Initially, a rinsing liquid at a first temperature (e.g., 60° C.) is stored in the processing bath 41. Then, the lifter 42 lowers the substrates W to the processing position and immerses the substrates W in the processing bath 41 (step S151: immersion process). This essentially starts the rough rinsing process. Initially, the temperature of the first rinsing liquid is relatively high, so that rapid cooling of the substrates W can be suppressed, and damage to the substrates W can be suppressed.
[0106] For example, when a predetermined time has elapsed since step S151, the rough rinsing processing unit 40 lowers the temperature of the first rinsing liquid to a second temperature (e.g., 25° C.) (step S152: temperature lowering step). Specifically, the valve 433 opens while the heater 434 is in a stopped state. As a result, the first rinsing liquid at a lower temperature is supplied from the nozzle 431 to the processing tank 41, and the first rinsing liquid overflowing from the top of the processing tank 41 is discharged to the outside through the upflow tank 411 and the drain pipe 442. As a result, the temperature of the first rinsing liquid in the processing tank 41 is lowered.
[0107] Then, when a specified processing time has elapsed from step S151, the lifter 42 lifts the plurality of substrates W from the processing position to the delivery position (step S153: lifting step).
[0108] As described above, in the above example, the temperature of the first rinsing liquid is decreased during the rough rinsing process. Therefore, the rate of replacement of phosphoric acid with the first rinsing liquid can be decreased while suppressing damage to the substrate W caused by rapid cooling. Therefore, it is possible to suppress the concentration of phosphoric acid in the pattern from decreasing more than necessary.
[0109] <Rising speed> Next, a first ascending speed when the lifter 32 of the phosphoric acid treating unit 30 lifts up the substrates W from the treating tank 31, and a second ascending speed when the lifter 42 of the rough rinsing unit 40 lifts up the substrates W from the treating tank 41 will be described. The first ascending speed here is, for example, the maximum value (or steady value or target value) of the ascending speed of the substrates W by the lifter 32, and the second ascending speed is, for example, the maximum value (or steady value or target value) of the ascending speed of the substrates W by the lifter 42. This second ascending speed is preferably equal to or lower than the first ascending speed. For example, the first ascending speed is set to 25 mm / sec or higher, and the second ascending speed is set to 25 mm / sec or lower.
[0110] In this case, the multiple substrates W are lifted up at a low lifting speed from the first rinsing liquid in the processing bath 41. This makes it possible to reduce the amount of liquid (mainly the first rinsing liquid) adhering to the non-pattern region of each substrate W.
[0111] This makes it possible to prevent the liquid from adhering to the transfer part 22, the carrier C2, the indexer robot 52, and the transfer robot 53 due to holding the substrate W after the rough rinsing process.
[0112] <Second embodiment> The substrate processing apparatus 10 according to the second embodiment is similar to the substrate processing apparatus 10 according to the first embodiment, except for an example of the configuration of the rough rinsing processor 40. The rough rinsing processor 40 according to the second embodiment is also referred to as a rough rinsing processor 40A below.
[0113] 8 is a diagram showing an example of the configuration of the rough rinsing processing unit 40 A. The rough rinsing processing unit 40 A includes a tray 41A, a lifter 42A, a rinsing liquid supply unit 43A, and a discharge unit 44A.
[0114] The vat 41A has a box shape, and its internal space corresponds to a processing space for processing a plurality of substrates W. The vat 41B can also be said to be a processing space forming member (or a chamber) that forms the processing space.
[0115] The lifter 42A has a structure similar to that of the lifter 42, and raises and lowers the multiple substrates W between a transfer position and a processing position. The transfer position is a position vertically above the vat 41A, and is a position where the multiple substrates W are transferred to and from the transport part 22. The processing position is a position where the multiple substrates W are stored in the processing space.
[0116] The rinsing liquid supply unit 43A supplies a first rinsing liquid to the multiple substrates W positioned in the processing space. The rinsing liquid supply unit 43A includes a nozzle 431A, a liquid supply pipe 432A, and a valve 433A. The nozzle 431A is provided in the vat 41A and ejects the first rinsing liquid onto the multiple substrates W positioned in the processing space. The nozzle 431A may be a nozzle that ejects the first rinsing liquid in the form of a liquid column onto the multiple substrates W, a shower nozzle that ejects the first rinsing liquid in the form of a shower onto the multiple substrates W, or a mist nozzle that ejects the first rinsing liquid in the form of a mist onto the multiple substrates W.
[0117] In the example of Fig. 8, the nozzle 431A is provided vertically above the multiple substrates W located at the processing position. Also, in the example of Fig. 8, a pair of nozzles 431A is provided. The nozzles 431A are provided on opposite sides of the substrate W in a horizontal direction parallel to the main surface of the substrate W (left-right direction in Fig. 8). That is, one nozzle 431A is provided on one side of the substrate W, and the other nozzle 431A is provided on the other side of the substrate W. Also, on both sides of the substrate W, the multiple nozzles 431A may be arranged side by side in the thickness direction of the substrate W (direction perpendicular to the paper surface in Fig. 8).
[0118] The nozzle 431A is connected to a rinsing liquid supply source through a liquid supply pipe 432A. A valve 433A is provided in the liquid supply pipe 432A. When the valve 433A is opened, a first rinsing liquid is supplied from the rinsing liquid supply source to the nozzle 431A through the liquid supply pipe 432A and is discharged from the discharge port of the nozzle 431A toward the multiple substrates W. In this way, the first rinsing liquid is supplied to the multiple substrates W.
[0119] The first rinsing liquid flows down along both main surfaces (i.e., the front and back surfaces) of each substrate W. The liquid flowing down from each substrate W is discharged to the outside through a discharge unit 44A connected to the bottom of the vat 41A. The discharge unit 44A includes a discharge pipe and a valve, not shown.
[0120] In the example of FIG. 8, a heater 434A is provided in the liquid supply pipe 432A. The heater 434A heats the first rinse liquid. As a result, the heated first rinse liquid is discharged from the nozzle 431A. The heater 434A heats the first rinse liquid so that the temperature of the first rinse liquid discharged from the nozzle 431A is higher than room temperature and lower than the temperature of phosphoric acid in the phosphoric acid treatment, for example, about 60° C. This can prevent the substrate W from being rapidly cooled by the first rinse liquid, and can reduce damage to the substrate W.
[0121] When the nozzle 431A supplies the first rinsing liquid to the plurality of substrates W, the first rinsing liquid flows down along both main surfaces of each substrate W, and therefore, with the passage of time from the start of the supply, the phosphoric acid adhering to both main surfaces of the substrate W is gradually replaced with the first rinsing liquid. In other words, a rough rinsing process is performed.
[0122] Also in the second embodiment, the rough rinsing process is completed when a sufficient amount of phosphoric acid remains inside the pattern of the substrate W. Specifically, the rinsing liquid supply unit 43A completes the discharge of the first rinsing liquid from the nozzle 431A when a specified processing time has elapsed since the nozzle 431A started discharging the first rinsing liquid. This processing time is a time that allows a sufficient amount of phosphoric acid to remain inside the pattern, and is set to, for example, about 1 to 2 minutes.
[0123] As described above, in the second embodiment, the first rinsing liquid is discharged toward a plurality of substrates W, thereby performing the rough rinsing process.
[0124] As in the first embodiment, the rough rinsing unit 40A may lower the temperature of the first rinsing liquid during the rough rinsing process. For example, the heater 434A may lower the amount of heat generated or terminate its operation during the rough rinsing process.
[0125] <Third embodiment> The substrate processing apparatus 10 according to the third embodiment is similar to the substrate processing apparatus 10 according to the first embodiment, except for an example of the configuration of the rough rinsing processor 40. Hereinafter, the rough rinsing processor 40 according to the third embodiment will also be referred to as a rough rinsing processor 40B.
[0126] 9 shows an example of the configuration of the rough rinsing processor 40B. Compared to the rough rinsing processor 40 according to the first embodiment, the rough rinsing processor 40B further includes a vapor supply unit 46. The vapor supply unit 46 supplies vapor of a second rinsing liquid into the chamber 49. The second rinsing liquid is a liquid having a latent heat of vaporization smaller than that of the first rinsing liquid, and is, for example, an organic solvent, more specifically, isopropyl alcohol.
[0127] The steam supply unit 46 includes a nozzle 461, an air supply pipe 462, and a valve 463. The nozzle 461 is provided in the chamber 49 vertically above the upper end of the processing bath 41. In the example of Fig. 9, a pair of nozzles 461 are provided. The two nozzles 461 are provided at an interval from each other in a horizontal direction parallel to the main surface of the substrate W.
[0128] The air supply pipe 462 connects the nozzle 461 to a steam supply source. A valve 463 is provided in the air supply pipe 462. When the valve 463 is opened, the steam of the second rinsing liquid is supplied from the steam supply source to the nozzle 461 through the air supply pipe 462, and is discharged from the discharge port of the nozzle 461 into the upper space of the chamber 49 (i.e., the space vertically above the processing tank 41).
[0129] In the example of Fig. 9, the chamber 49 is provided with an exhaust unit 47. The exhaust unit 47 exhausts gas within the chamber 49. In the example of Fig. 9, the exhaust unit 47 includes an exhaust pipe 471 and a suction mechanism 472. An upstream end of the exhaust pipe 471 is connected to, for example, the bottom of the chamber 49. The suction mechanism 472 is provided in the exhaust pipe 471, and sucks gas within the chamber 49 through the exhaust pipe 471. The suction mechanism 472 is, for example, a pump.
[0130] 10 is a flowchart showing an example of the operation of the substrate processing apparatus 10 according to the third embodiment. In the third embodiment, compared to the first embodiment, a rough drying process (step S17: rough drying process step) is further performed after the rough rinsing process (step S15).
[0131] The rough drying process is a process for removing at least a part of the liquid adhering to the area outside the pattern of each substrate W. That is, this rough drying process does not attempt to remove phosphoric acid within the pattern of the substrate W, but mainly reduces the liquid adhering to the area outside the pattern.
[0132] As a specific example, the rough rinsing processing unit 40B exposes a plurality of substrates W after the rough rinsing processing to an atmosphere of vapor of the second rinsing liquid. First, the vapor supply unit 46 supplies the vapor of the second rinsing liquid to the upper space in the chamber 49. This allows the upper space to be filled with an atmosphere of vapor of the second rinsing liquid. The vapor supply unit 46 may start supplying the vapor of the second rinsing liquid before the start of the rough drying processing. More specifically, the vapor supply unit 46 may start supplying the vapor of the second rinsing liquid before or during the start of the rough rinsing processing (step S15). This allows an atmosphere of vapor of the second rinsing liquid to be formed in the space above the processing tank 41 during the rough rinsing processing.
[0133] Then, when the lifter 42 lifts the substrates W into the upper space, the substrates W can be exposed to an atmosphere of vapor of the second rinsing liquid. This essentially starts the rough drying process.
[0134] The vapor of the second rinsing liquid acts on the area outside the pattern of the substrate W, so that the liquid (mainly the first rinsing liquid) adhering to the area outside the pattern is replaced by the second rinsing liquid, and the liquid flows down from the substrate W and is removed from the substrate W. In addition, since the second rinsing liquid evaporates easily, the area outside the pattern can be dried more effectively. On the other hand, the action of the vapor of the second rinsing liquid makes it difficult for the phosphoric acid inside the pattern to be replaced by the second rinsing liquid, so that the phosphoric acid in the second pattern can be left behind. Therefore, collapse of the pattern of the substrate W after the rough drying process can be suppressed or avoided.
[0135] Then, for example, when a preset time has elapsed from the start of step S17, the vapor supply unit 46 stops supplying the vapor of the second rinsing liquid. Then, the lid of the chamber 49 opens, and the lifter 42 lifts the multiple substrates W to the transfer position.
[0136] Incidentally, before the lid of chamber 49 is opened, the vapor of the second rinsing liquid in chamber 49 may be exhausted by exhaust unit 47. In the case where rough rinsing processing unit 40B includes a nitrogen gas supply unit that supplies nitrogen gas into chamber 49, nitrogen gas may be supplied into chamber 49. This allows the vapor of the second rinsing liquid to be effectively exhausted from chamber 49.
[0137] Next, similarly to the first embodiment, the third batch transfer process (step S16) and subsequent processes are carried out.
[0138] As described above, in the third embodiment, the rough drying process is performed. In this rough drying process, while leaving phosphoric acid in the pattern, at least a part of the liquid adhering to the area outside the pattern of the substrate W is removed. Therefore, even if each of the transfer part 22, the carrier C2, the indexer robot 52, and the transfer robot 53 holds the substrate W, it is possible to prevent the liquid from adhering to the carrier C2 and the transfer device. Therefore, it is possible to prevent the carrier C2 and the transfer device from being contaminated by the liquid.
[0139] <Fourth embodiment> In the fourth embodiment, the carrier C2 will be described. Figures 11 and 12 are diagrams that show an example of the configuration of the carrier C2 according to the fourth embodiment. Figure 11 shows a front view of the carrier C2, and Figure 12 shows an enlarged view of an area R1 in Figure 11.
[0140] Carrier C2 includes an upper member 81, a lower member 82, and a sidewall 83. The upper member 81 and the lower member 82 have, for example, a plate-like shape and are provided with their thickness direction aligned along the vertical direction. The upper member 81 and the lower member 82 are provided facing each other in the vertical direction. The sidewall 83 is a member that connects the peripheral edges of the upper member 81 and the lower member 82. One side of carrier C2 (the front side of the paper) does not have a sidewall 83 and is open. The substrate W is inserted into and removed from carrier C2 through the opening of carrier C2.
[0141] As shown in Fig. 11, a plurality of protrusions 831 are provided on the inner wall surface of the side wall 83, lined up at intervals in the vertical direction. Each protrusion 831 protrudes inward from the side wall 83. Thus, a plurality of grooves 832 are formed on the inner wall surface of the side wall 83. Each groove 832 corresponds to a space between two adjacent protrusions 831. An end of the substrate W is inserted into each groove 832 and supported by the protrusions 831. Fig. 12 shows a region R1 in which the substrate W is stored in the carrier C2.
[0142] 12, a water-absorbent member 833 is provided on the lower surface (i.e., the upper surface of the protrusion 831) and side surfaces of the groove 832. The water-absorbent member 833 is a member having water-absorbency, and is made of a water-absorbent material such as nonwoven fabric or diatomaceous earth.
[0143] A part of the water absorbing member 833 provided on the lower surface of the groove 832 contacts the lower surface of the substrate W to support the substrate W. That is, the water absorbing member 833 contacts a part of the non-pattern area of each substrate W. Thus, liquid adhering to the lower surface of the substrate W is absorbed by the water absorbing member 833. In addition, a part of the water absorbing member 833 provided on the side surface of the groove 832 may contact the side surface of the substrate W. In this case, the liquid adhering to the side surface of the substrate W is also absorbed by the water absorbing member 833.
[0144] For comparison, consider a structure that does not include the water absorbing member 833. In this case, liquid adhering to the lower surface of the substrate W can flow to the protrusion 831, flow along the upper surface and inner circumferential edge of the protrusion 831, and fall onto the substrate W below. This can contaminate the substrate W below.
[0145] In contrast to this, in the fourth embodiment, since the water absorbing member 833 is provided, it is possible to suppress or avoid the movement of liquid via the protrusions 831. As a result, contamination of the substrate W can be suppressed or avoided.
[0146] 12, when the water absorbing member 833 is also provided on the side surface of the groove 832, when the liquid adhering to the side surface of the substrate W is absorbed by the water absorbing member 833, the liquid on the peripheral portion of the surface of the substrate W also moves toward the water absorbing member 833 due to surface tension and can be absorbed by the water absorbing member 833. Therefore, the liquid on the peripheral portion of the surface of the substrate W can also be reduced.
[0147] On the other hand, the water absorbing member 833 may cause phosphoric acid in the pattern on the surface of the substrate W to move to the peripheral edge side of the substrate W due to capillary action and be absorbed by the water absorbing member 833. This is undesirable because it may cause the pattern to collapse.
[0148] Fig. 13 is a diagram illustrating an example of another configuration of the carrier C2, and shows an enlarged view of region R1 in Fig. 11. In the example of Fig. 13, the water absorbing member 833 is provided so as to avoid the side surface of the groove 832. In other words, the water absorbing member 833 is not provided on the entire side surface of the groove 832, but is provided only on the lower surface of the groove 832. This makes it possible to more reliably prevent phosphoric acid in the pattern of the substrate W from being absorbed by the water absorbing member 833. As a result, it is possible to more reliably prevent the pattern from collapsing.
[0149] As described above, the substrate processing apparatus 10 and the substrate processing method have been described in detail, but the above description is merely an example in all respects, and the substrate processing apparatus 10 and the substrate processing method are not limited thereto. It is understood that countless modified examples not illustrated can be imagined without departing from the scope of this disclosure. The configurations described in the above embodiments and modified examples can be appropriately combined or omitted as long as they are not mutually contradictory.
[0150] For example, in the above example, the substrate processing apparatus 10 has the batch-type phosphoric acid processor 30 and the rough rinse processor 40 provided in the housing 29, and the single-wafer processor 60 provided in a housing 59 different from the housing 29. The inter-apparatus transport unit 70 transports the carrier C2 between the housing 29 and the housing 59. However, this is not necessarily limited to this. The batch-type phosphoric acid processor 30, the rough rinse processor 40, and the single-wafer processor 60 may be provided in a common housing. A transport unit for transporting the substrate W between the rough rinse processor 40 and the single-wafer processor 60 is provided in this housing, and a posture change unit (e.g., posture change unit 24) is provided in the transport unit. The substrate processing apparatus 10 in which the batch-type phosphoric acid processor 30, the rough rinse processor 40, and the single-wafer processor 60 are provided in such a single housing may also be called a hybrid processing apparatus.
[0151] In the above example, the substrate W is provided with the laminated structure 90 as a three-dimensional structure (pattern), but this is not necessarily limited to this. The three-dimensional structure includes at least one of a wiring pattern, an insulating film pattern, and a semiconductor pattern. For example, when the aspect ratio of the pattern is 10 or more and the pattern width is 50 nm or less, the pattern is likely to collapse. Therefore, in this case, the substrate processing apparatus 10 is particularly effective. [Explanation of symbols]
[0152] 10 Substrate processing equipment 24 Posture conversion unit 30 Phosphate treatment section 31 Treatment tank 40 Rough Rinse Processing Section 50 Single-wafer processing equipment (second processing equipment) 51 Loading Port 60 Single-wafer processing section 833 Water-absorbing material S13 Phosphate treatment process (step) S15 Rough rinsing process (step) S152 Temperature reduction step S16 1st process (step) S17 Rough drying process (step) S20 2nd process (step) S21 3rd process (step) S23 Single wafer drying process (step) S24 4th process (step) C2 1st Carrier (Carrier) C3 2nd Carrier (Carrier) W substrate
Claims
1. a phosphoric acid treatment step of immersing a plurality of substrates in phosphoric acid in a treatment tank; a rough rinsing process step of replacing a part of the phosphoric acid attached to the plurality of substrates with a first rinsing solution to such an extent that the phosphoric acid remains in the patterns of the plurality of substrates after the phosphoric acid treatment process; a single-wafer drying process step of drying the plurality of substrates one by one after the rough rinsing process step; A substrate processing method comprising:
2. 2. The substrate processing method according to claim 1, The substrate processing method, wherein the rough rinsing process is terminated when a concentration of the phosphoric acid in the pattern becomes 50% or more.
3. 3. The substrate processing method according to claim 1, further comprising the steps of: The substrate processing method, wherein the rough rinsing process step includes a temperature reducing step of reducing a temperature of the first rinsing liquid.
4. 4. A substrate processing method according to claim 1, further comprising the steps of: The substrate processing method further comprises a rough drying process step between the rough rinsing process step and the single wafer drying process step, for removing at least a portion of liquid adhering to non-pattern regions of the plurality of substrates where the pattern is not formed.
5. 5. The substrate processing method according to claim 4, further comprising the steps of: In the rough drying process, the plurality of substrates are exposed to an atmosphere of vapor of a second rinsing liquid having a smaller latent heat of vaporization than the first rinsing liquid.
6. 6. A substrate processing method according to claim 1, further comprising the steps of: The phosphoric acid treatment step includes: lowering the plurality of substrates to immerse them in the phosphoric acid in the treatment tank; lifting the substrates out of the processing bath by lifting the substrates at a first lifting speed; Including, The rough rinsing treatment step includes: lowering the plurality of substrates to immerse them in the first rinsing liquid; lifting the substrates out of the first rinse liquid by lifting the substrates at a second lifting speed that is equal to or lower than the first lifting speed; A method for processing a substrate, comprising:
7. 7. A substrate processing method according to claim 1, further comprising the steps of: a first step of transporting the plurality of substrates to a first carrier after the rough rinsing step; a second step of transporting the first carrier to a load port of a single wafer processing apparatus after the first step; a third step of transporting the plurality of substrates one by one from the first carrier of the load port to a single wafer processing unit between the second step and the single wafer drying processing step; a fourth step of transporting the substrate from the single-wafer processing section to a second carrier of the load port after the single-wafer drying processing step; A substrate processing method comprising:
8. 8. The substrate processing method according to claim 7, further comprising the steps of: A substrate processing method, wherein the first carrier includes a water absorbing member that contacts a portion of an outside-pattern area of each of the plurality of substrates where the pattern is not formed.
9. a phosphoric acid processing unit having a processing tank and immersing a plurality of substrates in phosphoric acid in the processing tank; a rough rinsing treatment section that replaces a part of the phosphoric acid attached to the plurality of substrates with a rinsing liquid to such an extent that the phosphoric acid remains inside the patterns of the plurality of substrates; a single-substrate processing section for drying the plurality of substrates one by one; The substrate processing apparatus includes:
10. The substrate processing apparatus according to claim 9, a posture changing unit that changes the postures of the plurality of substrates between a horizontal posture and an upright posture, The phosphoric acid treatment unit immerses the plurality of substrates in an upright position in the phosphoric acid in the treatment tank, The single wafer processing section is a substrate processing apparatus that dries substrates in a horizontal position.
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