Developing method and developing apparatus

Abstract

A developing process method and a developing process apparatus are involved. The number of defects when forming a resist film with a large contact angle with water is reduced. The developing process method develops a resist film on a substrate, including: step (A), supplying a developing solution to the substrate to develop the resist film and form a resist pattern; step (B), supplying an aqueous cleaning solution to the developed substrate and cleaning the substrate with the aqueous cleaning solution; step (C), coating an aqueous solution of a water-soluble polymer on the substrate that has been cleaned with the aqueous cleaning solution to form a hydrophilic layer having hydrophilicity on the substrate surface; and step (D), cleaning the substrate on which the hydrophilic layer has been formed with a rinsing solution. The above step (B) includes step (a) of accelerating the rotation speed of the substrate and step (b) of decelerating the rotation speed of the substrate after step (a) until the start of step (C). The deceleration rate in step (b) is less than the acceleration rate in step (a).

Description

Technical Field

[0001] The present disclosure relates to a development processing method and a development processing apparatus. Background Art

[0002] In Patent Document 1, in order to prevent pattern collapse when forming a resist pattern of lines / spaces, the following method is disclosed: two or more types of rinsing liquids are used in the rinsing step during resist pattern development. In the method disclosed in Patent Document 1, in the rinsing liquid used in the first half of the rinsing step, the surface of the resist exposed to the developer treatment is exposed to promote the modification of the resist surface, and the contact angle between the rinsing liquid used in the second half of the step and the resist surface is adjusted to a desired angle.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Laid-Open No. 5-29936 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] The technology of the present disclosure can reduce the number of defects when forming a resist film having a large contact angle with respect to a rinsing liquid.

[0008] Solutions for Solving the Problems

[0009] One aspect of the present disclosure is a development processing method for developing a resist film on a substrate, the development processing method including the following steps: Step (A), supplying a developer to the substrate to develop the resist film to form a resist pattern; Step (B), supplying an aqueous cleaning liquid to the developed substrate and cleaning the substrate with the aqueous cleaning liquid; Step (C), coating an aqueous solution of a water-soluble polymer on the substrate that has been cleaned with the aqueous cleaning liquid to form a hydrophilic layer having hydrophilicity on the surface of the substrate; and Step (D), cleaning the substrate having the hydrophilic layer formed thereon with a rinsing liquid. The step (B) includes the following steps: Step (a), accelerating the rotation speed of the substrate; and Step (b), after the step (a), until the start of the step (C), decelerating the rotation speed of the substrate, and the deceleration rate in the step (b) is less than the acceleration rate in the step (a).

[0010] Effects of the Invention

[0011] According to the present disclosure, the number of defects when forming a resist film having a large contact angle with respect to a rinsing liquid can be reduced. Brief Description of the Drawings

[0012] Figure 1 Longitudinal cross-sectional view showing an outline of the configuration of the developing processing apparatus according to the first embodiment.

[0013] Figure 2 Transverse cross-sectional view showing an outline of the configuration of the developing processing apparatus according to the first embodiment.

[0014] Figure 3 Showing Figure 1 Flowchart showing an example of the developing process in the developing processing apparatus.

[0015] Figure 4 Graph showing the rotational speed of the wafer at each time point in the cleaning process and the subsequent developing process.

[0016] Figure 5 Partially enlarged cross-sectional view showing the appearance of the wafer during the developing process.

[0017] Figure 6 Cross-sectional view showing the appearance of the wafer in the drying process described later in the developing process.

[0018] Figure 7 Graph for explaining the effects of the first embodiment.

[0019] Figure 8 Transverse cross-sectional view showing an outline of the configuration of the developing processing apparatus according to the second embodiment.

[0020] Figure 9 Showing Figure 8 Graph showing the rotational speed of the wafer at each time point in the cleaning process and the subsequent developing process in the developing processing apparatus.

[0021] Explanation of Reference Signs

[0022] 1, 1a Developing processing apparatus

[0023] 20 Rotating chuck

[0024] 21 Chuck driving unit

[0025] 33 Developing solution supply nozzle

[0026] 36 DIW supply nozzle

[0027] 37 Aqueous solution supply nozzle

[0028] 38 Mixed solution supply nozzle

[0029] 40 Nozzle driving unit

[0030] 200 Control unit

[0031] F1 Hydrophilic layer

[0032] R resist pattern

[0033] W wafer Detailed implementation mode

[0034] In the lithography process of the manufacturing process of semiconductor devices and the like, in order to form a specified resist pattern on a semiconductor wafer (hereinafter referred to as "wafer"), a series of processes are carried out. The above series of processes include, for example: a resist coating process of supplying a resist solution to the wafer to form a resist film; an exposure process of exposing the resist film; a development process of supplying a developer to the exposed resist film to develop it, and the like.

[0035] In the above development process, for example, a developer is supplied to the wafer, a liquid film of the developer is formed on the wafer surface, and the wafer is developed. Then, a cleaning liquid such as pure water is supplied to the wafer, and the wafer is rotated at high speed to be cleaned. Through this cleaning, the dissolution products generated in the developer on the wafer during development are removed.

[0036] However, in recent years, with the progress of exposure technology and the like, the miniaturization of semiconductor devices has further advanced, and fine and high aspect ratio resist patterns have emerged. In fine resist patterns and resist patterns with a high aspect ratio, problems occur if the cleaning liquid remains on the wafer during the above development. For example, in the case where the resist pattern is a line / space pattern, when the cleaning liquid remains between the patterns, so-called pattern collapse occurs due to the remaining cleaning liquid.

[0037] In Patent Document 1, in order to prevent the occurrence of pattern collapse of the line / space pattern as described above, the following solution is disclosed: two or more types of rinsing liquids are used in the rinsing process of cleaning with a rinsing liquid during resist pattern development. In the method disclosed in Patent Document 1, in the rinsing liquid used in the first half process of the rinsing process, the resist surface that has been treated with the developer is exposed, the modification of the resist surface is promoted, and the contact angle between the rinsing liquid used in the second half process and the resist surface is adjusted to a desired angle.

[0038] It should be noted that the stress σ generated in the rinsing liquid remaining between the patterns, that is, the force in the direction parallel to the substrate generated by the cleaning liquid remaining between the patterns in the pattern, and the contact angle θ of the resist film with respect to the rinsing liquid and the surface tension γ of the cleaning liquid are in the following relationship.

[0039] σ∝γcosθ…(Equation 1)

[0040] Therefore, as a material of the resist film, a material with high water repellency is sometimes used.

[0041] However, the technology of Patent Document 1 is a technology related to a resist film with a contact angle of 0° with respect to water as a rinsing liquid, that is, a resist film with low water repellency.

[0042] In addition, even when using a highly water-repellent resist film, if miniaturization is advanced, pattern collapse occurs when there is a developing solution remaining between the patterns of a line / space pattern during development.

[0043] Furthermore, if the developing solution remains between the patterns, that is, on the wafer, the dissolution products contained in the developing solution also remain on the wafer. The dissolution products remaining on the wafer cause defects. Defects resulting from the dissolution products remaining on the wafer are a common problem even when the resist pattern is other than a line / space pattern (for example, in the case of a hole pattern or a pillar pattern), and moreover, regardless of the pattern density, that is, regardless of the number of concave and convex portions of the patterns in a certain area, it becomes a problem.

[0044] Therefore, the technology of the present disclosure reduces the number of defects when using a highly water-repellent resist film, that is, reduces the number of defects when forming a resist film having a large contact angle with respect to the developing solution.

[0045] Hereinafter, the developing process method and the developing process apparatus of the present embodiment will be described with reference to the accompanying drawings. It should be noted that in this specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and thus redundant description is omitted.

[0046] (First Embodiment)

[0047] Figure 1 and Figure 2 are a longitudinal sectional view and a transverse sectional view showing an outline of the configuration of the developing process apparatus 1 of the first embodiment.

[0048] The developing process apparatus 1 has a processing container 10 capable of sealing the inside, as Figure 1 shown. A carry-in / carry-out port (not shown) for the wafer W as a substrate is formed on the side surface of the processing container 10.

[0049] Inside the processing container 10, a rotating chuck 20 for holding the wafer W and rotating it around a vertical axis is provided. The rotating chuck 20 is freely configured to rotate at various speeds by a chuck driving unit 21 (for example, an engine or the like) as a rotating mechanism. In addition, a lifting driving mechanism such as a cylinder (not shown) is provided on the chuck driving unit 21, and the rotating chuck 20 is freely configured to be lifted by the lifting driving mechanism.

[0050] A cup 22 is provided so as to surround the periphery of the wafer W held by the rotating chuck 20. The cup 22 is used to block the liquid scattered or dropped from the wafer W and recover it.

[0051] As Figure 2 shown, on the negative X-direction side ( Figure 2 the downward direction) of the cup 22, a portion is formed along the Y-direction ( Figure 2rails 30A and 30B extending in the left-right direction (in the left-right direction of the figure). The rails 30A and 30B are formed, for example, from the outside on the negative Y-direction side (the left direction in the figure) of the cup 22 to the outside on the positive Y-direction side (the right direction in the figure) of the cup 22. Arms 31 and 32 corresponding to the rails 30A and 30B are respectively installed. Figure 2 to the outside on the positive Y-direction side ( Figure 2 the right direction in the figure) of the cup 22.

[0052] The developing solution supply nozzle 33 for supplying the developing solution is supported by the first arm 31. The first arm 31 is freely movable on the rail 30A by a nozzle driving unit 34 serving as a moving mechanism. Thus, the developing solution supply nozzle 33 can move from a standby unit 35 provided outside on the negative Y-direction side of the cup 22 to above the central portion of the wafer W in the cup 22. In addition, by the nozzle driving unit 34, the first arm 31 is freely movable up and down, and the height of the developing solution supply nozzle 33 can be adjusted. As the developing solution, for example, tetramethylammonium hydroxide (TMAH) is used.

[0053] The DIW supply nozzle 36, the aqueous solution supply nozzle 37, the mixed solution supply nozzle 38, and the gas supply nozzle 39 are supported by the second arm 32.

[0054] The second arm 32 is freely movable on the rail 30B by a nozzle driving unit 40 serving as a moving mechanism. Thus, the nozzles 36 to 39 can move from a standby unit 41 provided outside on the positive Y-direction side of the cup 22 to above the central portion of the wafer W in the cup 22. In addition, by the nozzle driving unit 40, the second arm 32 is freely movable up and down, and the heights of the nozzles 36 to 39 can be adjusted.

[0055] The DIW supply nozzle 36 supplies DIW (Deionized Water). DIW is used as an aqueous cleaning solution and a rinsing solution. That is, the DIW supply nozzle 36 functions as a cleaning solution supply nozzle and a rinsing solution supply nozzle.

[0056] The aqueous solution supply nozzle 37 supplies an aqueous solution of a water-soluble polymer. The aqueous solution of the water-soluble polymer is used to reduce the contact angle of the resist pattern formed by developing the resist film with the developing solution with respect to water.

[0057] The water-soluble polymer contained in the aqueous solution of the water-soluble polymer is, for example, a homopolymer or copolymer of a monomer containing a hydrophilic group, or a polycondensate having a hydrophilic group. Specific examples of the water-soluble polymer include: acrylic acid, methacrylic acid, fluoroacrylic acid, perfluoroalkyl acid, vinyl alcohol, vinylpyrrolidone, acrylate, methacrylate, polyvinyl alcohol (including partially saponified products), polyacrylic acid, polymethacrylic acid, polyvinyl methyl ether, polyvinylpyrrolidone, polyethylene glycol, polyvinyl acetal (including partially acetalized products), polyethyleneimine, polyethylene oxide, styrene-maleic anhydride copolymer, polyvinylamine, polyallylamine, oxazoline group-containing water-soluble resin, water-soluble melamine resin, water-soluble urea resin, alkyd resin or sulfonamide, and salts formed therefrom. Moreover, polyglycerol can also be used as the water-soluble polymer. These water-soluble polymers can be used alone or in combination of two or more. The concentration of the water-soluble polymer in the above aqueous solution is preferably less than 10%, more preferably less than 5%.

[0058] A surfactant can be added to the above aqueous solution. Specific examples of the surfactant include: sorbitan monooleate, glycerol α-monoleate, polyethylene glycol sorbitan fatty acid ester, polyethylene glycol linear alkyl ether, polyethylene glycol phenyl ether linear alkyl addition type, branched alkyl addition type, acetylene glycol, anionic sodium laurate, sodium stearate, sodium oleate, sodium dodecyl sulfate or sodium dodecylbenzenesulfonate. These surfactants can be used alone or in combination of two or more. The concentration of the surfactant in the above aqueous solution is preferably less than 5%.

[0059] Furthermore, the above aqueous solution is preferably acidic. Specifically, the pH of the above aqueous solution is preferably 3 to 6.

[0060] The mixed liquid supply nozzle 38 supplies a mixed liquid of a surfactant solution and pure water. The above mixed liquid is used as a rinsing liquid. That is, the mixed liquid supply nozzle 38 functions as a rinsing liquid supply nozzle. Since the mixed liquid used as this rinsing liquid contains a surfactant, the contact angle with the wafer W is smaller than that of an aqueous rinsing liquid. Specific examples of the surfactant melted in the surfactant solution are the same as those above. It should be noted that hereinafter, the mixed liquid of a surfactant solution and pure water may sometimes be referred to as a "surfactant-containing rinsing liquid".

[0061] The gas supply nozzle 39 supplies a gas. Specifically, the gas supply nozzle 39 supplies a gas (such as N2 gas) to the wafer W when drying the rinsing liquid on the wafer W.

[0062] A liquid supply mechanism 100 for supplying corresponding liquids to each nozzle is connected to the developing solution supply nozzle 33, the DIW supply nozzle 36, the aqueous solution supply nozzle 37, and the mixed solution supply nozzle 38. The liquid supply mechanism 100 has, for each nozzle: a pump (not shown) for pumping each liquid, a supply valve (not shown) for switching the supply and supply stop of each liquid, and the like.

[0063] In addition, a gas supply mechanism 110 for supplying gas to the gas supply nozzle 39 is connected thereto. The gas supply mechanism 110 has: a supply valve (not shown) for switching the supply and supply stop of the gas, and the like.

[0064] In the above-described developing processing apparatus 1, as Figure 1 shown, a control unit 200 is provided. The control unit 200 is, for example, a computer including a CPU, a memory, and the like, and has a program storage unit (not shown). A program for controlling various processes in the developing processing apparatus 1 is stored in the program storage unit. In addition, a program for controlling the nozzle driving units 34, 40, the liquid supply mechanism 100, the gas supply mechanism 110, etc., to implement the developing process described later is also stored in the program storage unit. It should be noted that the above program is recorded on a computer-readable storage medium and can be installed in the control unit 200 from this storage medium. Part or all of the program can be implemented in a dedicated hard wafer (circuit board).

[0065] Here, an example of the developing process in the developing processing apparatus 1 is described using Figures 3 to 5 for illustration. Figure 3 is a flowchart showing an example of the developing process. Figure 4 is a diagram showing the rotation speed of the wafer W (hereinafter referred to as "wafer rotation speed") at each moment during the developing process, showing the cleaning process and thereafter described later. Figure 5 is a partially enlarged cross-sectional view showing the state of the wafer W during the developing process. Figure 6 is a cross-sectional view showing the state of the wafer W during the drying process described later in the developing process.

[0066] Note that in the following description, a lower layer film such as SiARC (Silicon-containing Anti-Reflective Coating) is formed on the surface of the wafer W loaded into the processing container 10, and a resist film is pre-formed on the lower layer film. In addition, the exposure process of the resist film and the subsequent heat treatment are completed. In the above exposure process, exposure for forming a line / space pattern is performed. Note that the contact angle of the resist film formed on the lower layer film of the wafer W with respect to water is large. In addition, the flow rate of each liquid in each of the following processes is as follows: 350 ml / min for DIW, 80 ml / min for the aqueous solution of the water-soluble polymer and the mixed solution. Note that the flow rate of DIW can be 250 to 450 ml / min, and the flow rate of the aqueous solution of the water-soluble polymer and the mixed solution can be 50 ml / min to 100 ml / min, preferably 75 - 90 ml / min.

[0067] (Step S1: Developing solution pooling formation process)

[0068] In the developing process, first, as Figure 3 shown, developing solution pooling is formed over the entire surface of the wafer W (Step S1). Specifically, the wafer W is loaded into the processing container 10 and placed and adsorbed on the rotating chuck 20. Then, the developing solution supply nozzle 33 moves above the wafer W, and the developing solution is discharged in a band shape from the developing solution supply nozzle 33. For example, when the wafer W rotates once, developing solution pooling is formed over the entire surface of the wafer W.

[0069] (Step S2: Static developing process)

[0070] After forming the developing solution pooling, the supply of the developing solution is stopped, and static developing is performed for a preset time while the wafer W is stationary (Step S2). Through this process, the developing of the resist film on the wafer W proceeds, and as Figure 5 (A) of shows, a resist pattern R is formed on the lower layer film U of the wafer W. Note that in this static developing, the DIW supply nozzle 36 moves above the central portion of the wafer W instead of the developing solution supply nozzle 33 retracting outside the cup 22.

[0071] (Step S3: Cleaning process)

[0072] After static developing, the wafer W is rotated, and for this wafer W, DIW as an aqueous cleaning liquid is supplied from the DIW supply nozzle 36, and the wafer W is cleaned (Step S3). Through this process, the developing solution and the dissolution products are removed. In addition, as Figure 5 (A) of and Figure 5As shown in (B), the film D of the developing solution on the resist pattern R is replaced by DIW, and a state where the film E of DIW is formed is obtained, and the liquid-based covering state can be maintained. The cleaning process of this step S3 is as Figure 4 shown, and includes the following acceleration process (step S3a) and deceleration process (step S3b).

[0073] (Step S3a: Acceleration process)

[0074] In the cleaning process, first, DIW is supplied to the rotating wafer W, and in the supply of this DIW, the rotation speed of the wafer is accelerated to a preset rotation speed (step S3a). Specifically, as Figure 4 shown, just after the supply of DIW starts, the rotation speed of the wafer is maintained at a low rotation speed (for example, 50 to 200 rpm), and then it is accelerated to a preset high rotation speed HRS1 (for example, 700 rpm or more and 1800 rpm or less). Thereby, DIW is uniformly spread in-plane on the wafer W. Then, after the acceleration, the rotation speed of the wafer is maintained at the above high rotation speed for a preset time. Thereby, the developing solution and the dissolution products on the wafer W are effectively discharged. It should be noted that in this example, the acceleration in the acceleration process is constant.

[0075] (Step S3b: Deceleration process)

[0076] After the acceleration process of step S3a, during the period until the hydrophilic layer formation process of step S4 immediately following the cleaning process of step S3 starts, the rotation speed of the wafer is decelerated (step S3b). In the acceleration process of step S3a immediately before the deceleration process starts, in order to discharge the developing solution and the like, the rotation speed of the wafer needs to be high. In contrast, in the hydrophilic layer formation process of step S4 immediately after the deceleration process ends, as will be described later, in order to form a film of an aqueous solution of a water-soluble polymer uniformly in-plane, the rotation speed of the wafer immediately after the hydrophilic layer formation process starts needs to be low. Therefore, this deceleration process is provided, and after the acceleration process of step S3a ends, it is decelerated to a preset low rotation speed (for example, 50 to 200 rpm) at the start of the hydrophilic layer formation process of step S4. It should be noted that in this example, the deceleration in the deceleration process is constant.

[0077] In addition, the deceleration in the deceleration process of step S3b is less than the acceleration in the acceleration process of step S3a, specifically, it is set to 200 rpm / s or less. This is to prevent a portion not covered by the film E of DIW from being generated at the peripheral portion of the wafer W.

[0078] When the deceleration process ends, after stopping the supply of DIW from the DIW supply nozzle 36, the aqueous solution supply nozzle 37 moves above the central portion of the wafer W.

[0079] (Step S4: Hydrophilic Layer Formation Process)

[0080] After the cleaning process, for the rotating wafer W, an aqueous solution of a water-soluble polymer (hereinafter sometimes simply referred to as "polymer aqueous solution") is applied, and a hydrophilic layer is formed on the surface of the wafer W including the surface with the resist pattern (Step S4). The hydrophilic layer formation process of this Step S4 is as Figure 4 shown, and includes an aqueous solution supply process (Step S4a) and a rotation maintenance process (Step S4b).

[0081] In addition, the time from the stop of the supply of DIW in the cleaning process of Step S3 to the start of the supply of the polymer aqueous solution in the process of this Step S4 is, for example, 0.7 seconds or less.

[0082] (Step S4a: Aqueous Solution Supply Process)

[0083] In the hydrophilic layer formation process, first, the polymer aqueous solution is supplied from the aqueous solution supply nozzle 37 to the rotating wafer W. In other words, while supplying the polymer aqueous solution to the wafer W, the wafer W is rotated. Through this process, the film E of DIW on the resist pattern R is replaced by the polymer aqueous solution, and as Figure 5 (C) shows, it becomes a state where a film F of the polymer aqueous solution is formed.

[0084] In this process, immediately after the supply of the polymer aqueous solution starts, the rotational speed of the wafer is maintained at a low rotational speed (for example, 50 to 200 rpm), and then accelerated to a preset high rotational speed (for example, 1000 to 2000 rpm). Thereby, the polymer aqueous solution spreads uniformly in-plane on the wafer W, and a film of this liquid is formed uniformly in-plane. After the above acceleration, the supply of the polymer aqueous solution from the aqueous solution supply nozzle 37 is stopped.

[0085] It should be noted that the supply time Tw1 of DIW in the cleaning process of Step S3 is longer than the supply time Tp of the polymer aqueous solution in this aqueous solution supply process.

[0086] (Step S4b: Rotation Maintenance Process)

[0087] After the aqueous solution supply process of Step S4a, the wafer is rotated for a preset time (Step S4b) in a state where the polymer aqueous solution is not supplied. Through this process, as Figure 5 (D) shows, a hydrophilic layer F1 is formed on the surface of the wafer W including the surface with the resist pattern R.

[0088] In this process, the rotation speed of the wafer is maintained, for example, at the above-described high rotation speed (e.g., 1000 to 2000 rpm) in the aqueous solution supply process of step S4a. Therefore, the liquid film at the peripheral portion of the wafer is attracted to the central portion of the wafer, and it is possible to prevent the recession where the peripheral portion of the wafer is exposed.

[0089] Then, the execution time of the rotation maintenance process is set to be longer than the execution time of the aqueous solution supply process of step S4a. In addition, the execution time of the rotation maintenance process is, for example, 6 seconds or more.

[0090] It should be noted that in the rotation maintenance process, the DIW supply nozzle 36 moves above the central portion of the wafer W.

[0091] (Step S5: Rinse process)

[0092] After the hydrophilic layer formation process, for the rotating wafer W, a rinse liquid is supplied, and the wafer W is cleaned (step S5). The rinse process of this step S5 is as Figure 4 shown, and includes a rinse liquid supply process (step S5a) and a drying process (step S5b). Then, the rinse liquid supply process includes: a first rinse liquid supply process (step S5a1) and a second rinse liquid supply process (step S5a2), and the drying process includes a first drying process (step S5b1) and a second drying process (step S5b2).

[0093] (Step S5a: Rinse liquid supply process)

[0094] The rinse liquid supply process of step S5a is a process of rotating the wafer W while supplying a rinse liquid to the wafer W on which the hydrophilic layer is formed.

[0095] (Step S5a1: First rinse liquid supply process)

[0096] Then, in the first rinse liquid supply process of step S5a1, which is the initial process of the rinse liquid supply process, for the rotating wafer W, DIW as the first rinse liquid is supplied from the DIW supply nozzle 36 (step S5a1). Through this process, the polymer aqueous solution on the resist pattern R is displaced by the DIW, as Figure 5As shown in (E), it becomes a state where the film G with DIW is formed. In this first rinse liquid supply process, in order to discharge the polymer aqueous solution, etc., a relatively high wafer rotation speed is required. On the other hand, in the second rinse liquid supply process of step S5a2 immediately after this process, in order to form a film of the rinse liquid containing a surfactant uniformly in-plane, the wafer rotation speed immediately after the start of the second rinse liquid supply process (that is, immediately after the supply of the rinse liquid containing a surfactant starts) needs to be low. Specifically, it is necessary to make the wafer rotation speed immediately after the start of the second rinse liquid supply process a speed lower than the maximum rotation speed in the first drying process (500 rpm or more and 1000 rpm or less). Therefore, in the first rinse liquid supply process, after maintaining the wafer rotation speed at a preset high rotation speed (for example, 1000 to 1500 rpm) for a preset time, deceleration is performed. Specifically, the wafer rotation speed is decelerated until the end of the first rinse liquid supply process to a preset low rotation speed LRS (500 rpm or more and 1000 rpm or less) lower than the maximum rotation speed HRS2 in the first drying process at the start of the second rinse liquid supply process. After this deceleration, the supply of DIW from the DIW supply nozzle 36 is stopped, and instead, the mixed liquid supply nozzle 38 moves above the central portion of the wafer W.

[0097] It should be noted that in this first rinse liquid supply process, a hydrophilic layer has already been formed on the surface of the resist pattern R. Therefore, the deceleration rate of the wafer rotation speed can be made greater than that in the deceleration process of step S3b, that is, the wafer rotation speed can be rapidly decreased. Thus, by making the deceleration rate of the wafer rotation speed in the second rinse liquid supply process greater than that in the deceleration process of step S3b, the time required for the first rinse liquid supply process can be shortened.

[0098] (Step S5a2: Second rinse liquid supply process)

[0099] After the first rinse liquid supply process, for the rotating wafer W, a rinse liquid containing a surfactant as the second rinse liquid is supplied from the mixed liquid supply nozzle 38 (step S5a2). Through this process, the aqueous solution of DIW on the resist pattern R is replaced with the rinse liquid containing a surfactant, as Figure 5As shown in (F), it becomes a state where the film H of the rinse liquid is formed. In this process, regarding the rotation speed of the wafer W, immediately after the supply of the rinse liquid containing the surfactant starts, it is set to a low rotation speed LRS (for example, 500 rpm or more and 1000 rpm or less), and then, after accelerating to a preset high rotation speed (for example, 1000 rpm), it is maintained at this high rotation speed for a preset time. As a result, the rinse liquid containing the surfactant spreads uniformly in-plane on the wafer W, and the film of the rinse liquid is formed uniformly in-plane. After the above film formation, the supply from the mixed liquid supply nozzle 38 is stopped, and instead of this nozzle 38, the gas supply nozzle 39 moves above the central portion of the wafer W.

[0100] It should be noted that the supply time Tw2 of DIW in the first rinse liquid supply process is longer than the supply time Tr of the rinse liquid containing the surfactant in the second rinse liquid supply process.

[0101] (Step S5b: Drying process)

[0102] The drying process of step S5b is a process of rotating the wafer in a state where no rinse liquid is supplied after the rinse liquid supply process of step S5a. Through this process, the rinse liquid on the wafer W is dried, and as Figure 5 shown in (G), the resist pattern R is exposed.

[0103] (Step S5b1: First drying process)

[0104] Then, in the first drying process of step S5b1, which is the initial process of the drying process, as Figure 6 shown in (A), in the central portion of the wafer W, while supplying gas to form a recess M in the above-mentioned film of the rinse liquid, the rotation speed of the wafer is accelerated to expand the recess M. The recess M becomes the starting point of drying. In this process, regarding the rotation speed of the wafer, for example, it is accelerated to the highest rotation speed HRS2 in this process, and then, it is maintained at this highest rotation speed HRS2 for a preset time. The above-mentioned highest rotation speed is, for example, 700 rpm or more and 1800 rpm or less, and more preferably 800 rpm or more and 1500 rpm or less. In addition, in this process, the rotation speed of the wafer can be accelerated to the above-mentioned highest rotation speed HRS2 at a constant acceleration, or can be accelerated step by step.

[0105] It should be noted that at the end of the first drying process, the gas supply is stopped, and the gas supply nozzle 39 retracts outside the cup 22. In addition, the position of the gas supply nozzle 39 in this process is fixed above the central portion of the wafer W.

[0106] (Step S5b2: Second drying process)

[0107] After the first drying process, as Figure 6As shown in (B), as the recess M expands, the rotation speed of the wafer is decelerated to a preset rotation speed RS (step S5b2). In this process, the rotation speed of the wafer is preferably decelerated to a preset rotation speed of, for example, 600 rpm or more. The above preset rotation speed is preferably 1500 rpm or less. After deceleration, the rotation speed of the wafer is maintained at this rotation speed RS for a preset time, and then the rotation of the wafer W is stopped.

[0108] It should be noted that the deceleration of the rotation speed of the wafer in the second drying process can be performed at a constant deceleration rate or stepwise.

[0109] After the rinsing process of step S5, the wafer W is taken out of the processing container 10, and the development process is completed.

[0110] As described above, the development process method of the present embodiment includes the following processes: a process of supplying a developer to the wafer W to develop the resist film and form a resist pattern; a process of supplying DIW to the developed wafer and cleaning the wafer W with DIW; a process of coating an aqueous polymer solution on the wafer W that has been cleaned with DIW to form a hydrophilic layer on the surface of the wafer W; and a process of cleaning the wafer W on which the hydrophilic layer has been formed with a rinsing liquid. According to this development process method, when a resist film with a large contact angle with water is formed on the wafer W, a hydrophilic layer is also formed on the wafer W, and the contact angle of the wafer W with water becomes lower. Therefore, it becomes difficult to remove the rinsing liquid when the wafer is rotated and dried, that is, the rinsing liquid tends to remain on the wafer W. Therefore, it is not easy to generate pattern collapse caused by the rinsing liquid remaining on the wafer W and defects caused by the dissolved products contained in the remaining rinsing liquid.

[0111] Here, different from the present embodiment, the deceleration process of step S3b is not performed, and the rotation speed of the wafer at the start of the hydrophilic layer formation process of step S4 remains at a high rotation speed state. In the above case, since the pattern surface has a high contact angle, etc., and the aqueous polymer solution is difficult to spread over the entire area of the wafer surface during the hydrophilic layer formation process of step S4, unevenness occurs in the formation state of the hydrophilic layer formed by the aqueous polymer solution. In contrast, in the present embodiment, the deceleration process of step S3b is performed, and at the start of the hydrophilic layer formation process of step S4, the rotation speed of the wafer W is decelerated from the above high rotation speed. Therefore, the aqueous polymer solution can be temporarily accumulated in the central portion of the wafer W, and then the rotation speed is increased, so that the aqueous polymer solution can be spread over the entire surface of the wafer W. Therefore, the formation state of the hydrophilic layer can be made uniform within the wafer surface.

[0112] In addition, different from this embodiment, the deceleration in the deceleration process of step S3b is made equal to the acceleration in the acceleration process of step S3a. In the above case, due to the rapid deceleration and the surface tension of the DIW, the DIW up to the crystal circumference on the film will concentrate toward the center of the wafer, and a portion not covered by the DIW will be generated at the crystal circumference. Thus, when the polymer aqueous solution is coated in the hydrophilic film forming process of step S4 following the DIW, the aqueous solution does not sufficiently spread to the crystal circumference, resulting in unevenness in the formation state of the hydrophilic layer. In contrast, in this embodiment, the deceleration in the deceleration process of step S3b is made smaller than the acceleration in the acceleration process of step S3a. Therefore, when the polymer aqueous solution is coated following the DIW, the entire wafer W is covered by the DIW, and thus, the formation state of the hydrophilic layer can be made uniform within the wafer surface.

[0113] That is, according to this embodiment, a state in which the wafer W is uniformly covered with the DIW is formed in advance, and the coating of the polymer aqueous solution is gradually started on the wafer W rotating at a low rotational speed. Therefore, the hydrophilic layer can be formed more uniformly within the wafer surface, and the liquid removal during rinsing can be suppressed. As a result, defects can be reduced.

[0114] Furthermore, in view of the coverage under the DIW, the deceleration in the deceleration process of step S3b is reduced in advance. Different from this embodiment, the acceleration in the acceleration process of step S3a is made equal to or less than the deceleration. In the above case, the processing efficiency (the discharge efficiency of the soluble product and the replacement efficiency from the film of the developer to the film of the DIW) in the cleaning process of step S3 is reduced, and the time required for the above cleaning process becomes longer. In this embodiment, the acceleration in the acceleration process of step S3a is greater than the deceleration in the deceleration process of step S3b. Therefore, it is possible to balance the maintenance of the coverage state under the DIW and the prevention of prolongation of the time of the cleaning process of step S3.

[0115] In addition, in this embodiment, the drying process of step S5b includes the following first drying process: In the central portion of the wafer W, while supplying gas to form a recess in the film of the rinsing liquid, the rotational speed of the wafer is accelerated, and the recess is expanded. In addition, the drying process of step S5b includes the following second drying process: While maintaining the supply of gas, the rotational speed of the wafer is decelerated as the recess expands. By forming a recess in the central portion of the wafer W, the amount of the rinsing liquid in the central portion of the wafer W where the centrifugal force is small is reduced. In addition, when the wafer W is dried by rotating and discharging the rinsing liquid thereafter, the recess becomes the starting point of drying, and it is easy to apply centrifugal force, and the liquid becomes easy to be discharged. Therefore, the risk of liquid residue can be reduced.

[0116] In addition, in the case of a line / space pattern, by forming the concave portion, a large difference in the remaining rinse liquid can be prevented between the spaces sandwiching the line pattern. The state of generating the "large difference" refers to the following state: for example, as shown in Figure 7 , a large amount of rinse liquid L remains in the space P2 adjacent to one side surface of the line pattern P1 with the line / space pattern, while no rinse liquid remains in the space P3 adjacent to the other side surface. If the "large difference in the remaining rinse liquid between the spaces sandwiching the line pattern" is generated, the surface tension acting on the line pattern will cause a large difference between one side surface and the other side surface of the line pattern, which becomes a cause of pattern collapse. According to the present embodiment, as described above, the large difference in the remaining rinse liquid can be prevented, so that the large difference in the surface tension can be prevented, and the occurrence of pattern collapse can be prevented.

[0117] Furthermore, in the present embodiment, after the concave portion expands outward to a certain extent, in order not to make the centrifugal force of the pattern near the interface between the concave portion and its outside excessive, the rotation speed is decelerated, so that pattern collapse is not likely to occur.

[0118] It should be noted that after the concave portion is formed by supplying gas, the concave portion can be expanded by rotating the wafer W in a state where the supply of gas is stopped.

[0119] It should be noted that the flow rate of the gas in the first drying step and the second drying step is preferably not so large as to blow off the surfactant-containing rinse liquid in the portion blown by the gas and expose the resist pattern. This is because when the exposure flow rate is higher, a large difference in the remaining rinse liquid is generated near the interface of the concave portion, and pattern collapse is likely to occur. In addition, there is a risk of pattern collapse under the pressure of the gas itself.

[0120] In addition, in the present embodiment, the maximum rotation speed HRS2 of the wafer W in the first drying step is 700 rpm or more and 1800 rpm or less.

[0121] The inventors of the present invention changed the conditions of the maximum rotation speed HRS2 of the wafer W in the first drying process and repeated the development process. In the development process performed, other processing conditions were set to the conditions within the range described above regarding the present embodiment. According to the research results of the inventors of the present invention, when the maximum rotation speed is lower than 700 rpm, many defects are generated in the entire wafer. If it exceeds 1800 rpm, there are few defects in the central portion of the wafer, but many defects are generated in the peripheral portion of the wafer. In contrast, when the maximum rotation speed is 700 rpm or more and 1800 rpm or less, there are few defects at least in the central portion of the wafer W where recesses are formed on the film of the rinsing liquid by gas supply. As a reason for the generation of many defects in the entire wafer when it is lower than 700 rpm, it is considered that: since the rotation speed of the wafer is low, the centrifugal force of the rinsing liquid acting on the wafer W is small, and this rinsing liquid remains on the wafer in a large amount. In addition, as a reason for the generation of many defects in the peripheral portion of the wafer when it exceeds 1800 rpm, it is considered that liquid removal of the rinsing liquid occurs in the peripheral portion of the wafer, and this rinsing liquid remains on the peripheral portion of the wafer.

[0122] Furthermore, in the present embodiment, in the second drying process, the rotation speed of the wafer is decelerated from the above-described maximum rotation speed in the first drying process to a preset speed of 600 rpm or more (hereinafter, the finally achieved wafer rotation speed).

[0123] The inventors of the present invention changed the finally achieved wafer rotation speed in order to study the range of the finally achieved wafer rotation speed in the second drying process and repeated the development process. In the development process performed, the maximum rotation speed in the first drying process was set to 1800 rpm, and other processing conditions were set to the conditions within the range described above regarding the present embodiment. According to the research results of the inventors of the present invention, when the finally achieved wafer rotation speed in the second drying process is lower than 600 rpm, many defects are generated in the entire wafer. If it is 600 rpm or more, there are few defects. In the case of being lower than 600 rpm, as a reason for the generation of many defects in the entire wafer, it is considered that the reason is that in the second drying process, although the boundary of the recess formed in the film of the rinsing liquid extends to the outside, if the rotation speed of the wafer is low, the centrifugal force acting on the rinsing liquid is small, and therefore, this rinsing liquid remains on the wafer W in a large amount.

[0124] It should be noted that the reason for decelerating the rotation speed of the wafer from the maximum rotation speed in the first drying process in the second drying process is that, without deceleration, liquid removal of the rinsing liquid occurs in the peripheral portion of the wafer, and this rinsing liquid remains on the peripheral portion of the wafer and becomes the cause of defects. It should be noted that the finally achieved wafer rotation speed in the second drying process is preferably 1500 rpm or less. According to the research results of the inventors of the present invention, this is because if the finally achieved wafer rotation speed exceeds 1500 rpm, many defects are generated in the outer peripheral portion of the wafer.

[0125] Furthermore, the developing process method of the present embodiment includes the following steps: a first rinsing liquid supply step of rotating the wafer W while supplying DIW to the wafer W formed with a hydrophilic layer; and a second rinsing liquid supply step of rotating the wafer W while supplying a rinsing liquid containing a surfactant to the wafer after the first rinsing liquid supply step. Moreover, in the first rinsing liquid supply step, after rotating the wafer W at a preset rotation speed, the rotation speed of the wafer W is decelerated until the end of the first rinsing liquid step, and set to a preset low rotation speed at the start of the second rinsing liquid supply step, which is lower than the maximum rotation speed in the first drying step. Thus, it is possible to maintain the coverage state of DIW unchanged and switch to the supply of a rinsing liquid containing a surfactant with a low surface tension.

[0126] The preset low rotation speed at the start of the second rinsing liquid supply step described above is, for example, 500 rpm or more and 1000 rpm or less.

[0127] The inventors repeated the developing process while changing the above-mentioned low rotation speed in order to study the range of the preset low rotation speed at the start of the second rinsing liquid supply step. In the developing process performed, other processing conditions were set to the conditions within the scope of the above description related to the present embodiment. Among them, in the second rinsing liquid supply step, the rotation speed of the wafer was kept constant without acceleration. According to the research results of the inventors, if the rotation speed in the second rinsing liquid supply step is 500 - 1000 rpm, there are few defects. When it is lower than 500 rpm, more defects are generated, but it is considered that the reason is that the rotation speed of the wafer is low, so the rinsing liquid containing a surfactant does not expand throughout the wafer surface. In addition, when it exceeds 1000 rpm, more defects are generated, but it is considered that the reason is that the rotation speed of the wafer is high, so liquid removal of the rinsing liquid occurs at the wafer peripheral edge portion, and the rinsing liquid remains on the wafer peripheral edge portion.

[0128] It should be noted that the rotation speed of the wafer in the second rinsing liquid supply step is more preferably always 1000 rpm or less. This is because, according to the evaluation of the inventors, when the second rinsing liquid expands on the wafer W, if the rotation speed of the wafer is too large, it is determined to be a poor coverage due to liquid removal, while if it is 100 rpm or less, there is no such poor coverage situation, and the processing can be carried out without problems.

[0129] In addition, in the present embodiment, the hydrophilic layer forming step of step S4 includes the following steps: an aqueous solution supply step of rotating the wafer W while supplying a polymer aqueous solution to the wafer W cleaned with DIW; and a rotation maintenance step of rotating the wafer W in a state where the polymer aqueous solution is not supplied after the aqueous solution supply step.

[0130] When forming a hydrophilic layer, if the supply of the polymer aqueous solution is continued for a long time, the absolute amount of the water-soluble polymer increases, and there is a risk that the water-soluble polymer remains as a residue. However, when the supply of the water-soluble polymer is stopped until the rotation of the wafer W stops, a retreat occurs, and the in-plane uniformity of the coverage by the polymer aqueous solution is impaired. In contrast, in the present embodiment, after the supply of the polymer aqueous solution is stopped, the rotation of the wafer W is continued. Therefore, the risk of the above-mentioned residue can be reduced, and in addition, the occurrence of retreat can be prevented, and the hydrophilic layer can be formed uniformly in the wafer plane.

[0131] Furthermore, in order to improve the cleanability, the rinsing liquid containing a surfactant is often adjusted to be acidic. Correspondingly, the polymer aqueous solution is sometimes adjusted to be acidic. However, in the above case, if the supply of the polymer aqueous solution is continued, there is also a concern that the pattern refinement progresses. As in the present embodiment, by stopping the supply of the polymer aqueous solution, this pattern refinement can also be prevented.

[0132] In addition, in the present embodiment, the supply time Tw1 of DIW in the cleaning step of step S3 is longer than the supply time Tp of the polymer aqueous solution in the aqueous solution supply step of step S4a. The DIW in the cleaning step of step S3 is used to discharge the developer and dissolution products, and as a result, the above discharge is also considered using the polymer aqueous solution. However, in the above case, the supply of the polymer aqueous solution becomes excessive, and sometimes the same residue risk as described above and pattern refinement when the polymer aqueous solution is acidic occur. In contrast, in the present embodiment, the supply time Tw1 of DIW is extended in advance, and the above discharge is performed using DIW. Therefore, it is not necessary to extend the supply time Tp of the polymer aqueous solution, and the risk of the above residue does not increase. In addition, by extending the supply time of DIW, a liquid film of DIW with low reactivity with other liquids can cover the entire wafer for the next process.

[0133] It should be noted that in the present embodiment, the supply time Tw2 of DIW in the first rinsing liquid supply step is longer than the supply time Tr of the rinsing liquid containing a surfactant in the second rinsing liquid supply step. If the supply time Tr of the rinsing liquid containing a surfactant is long, the supply of the rinsing liquid becomes excessive, and pattern refinement sometimes occurs when the rinsing liquid is acidic. According to the present embodiment, this pattern refinement can be prevented.

[0134] In addition, in the present embodiment, the time from the stop of the supply of DIW in the cleaning step of step S3 to the start of the supply of the polymer aqueous solution in the hydrophilic layer forming step of step S4 (hereinafter, sometimes referred to as "switching time to the aqueous solution") is set to 0.7 seconds or less.

[0135] Furthermore, the time from when the supply of DIW in the first rinse liquid supply step is stopped to when the supply of the surfactant-containing rinse liquid in the second rinse liquid supply step is started (hereinafter, “rinsing liquid switching time”) is also preferably set to 0.7 seconds or less.

[0136] In order to study the range of the above-mentioned rinsing liquid switching time, the inventors of the present invention changed the above-mentioned rinsing liquid switching time and repeated the development process. In the development process performed, other processing conditions were set to the conditions within the above-mentioned description range related to the present embodiment. According to the research results of the inventors of the present invention, if the above-mentioned rinsing liquid switching time is less than 0.7 seconds, there are fewer defects. When it exceeds 0.7 seconds, more defects are generated in the peripheral portion of the wafer, but it is believed that the reason is that the above-mentioned rinsing liquid switching time is long, so the DIW at the peripheral portion of the wafer is dried, and the rinsing liquid containing a surfactant does not extend to the peripheral portion of the wafer.

[0137] The research results of the rinse liquid switching time can also be applied to the switching time of the aqueous solution. This is because, regardless of the case of switching the rinse liquid or the aqueous solution, the liquid used before the switch is common to DIW, and the rotation speed of the wafer W after the switch is the same.

[0138] In the present embodiment, the maximum rotation speed of the wafer W in the acceleration step of step S3 a of the cleaning step of step S3 is set to be greater than or equal to 700 rpm and less than or equal to 1800 rpm.

[0139] In order to study the range of the maximum rotational speed of wafer W in the acceleration process of step S3a, the inventors of the present invention changed the above-mentioned maximum rotational speed and repeated the development process. In the development process performed, other processing conditions are set to the conditions within the above description range related to the present embodiment. According to the research results of the inventors of the present invention, if the maximum rotational speed in the acceleration process is greater than 700rpm and less than 1800rpm, there will be fewer defects. In the case of less than 700rpm, more defects are generated, but it is believed that the reason is that the wafer rotation speed is low, so the centrifugal force acting on DIW, etc. is small, and the dissolved product cannot be discharged. In addition, in the case of exceeding 1800rpm, more defects are generated, but it is believed that the reason is that the wafer rotation speed is high, so a portion not covered with DIW is generated at the peripheral portion of the wafer, and a hydrophilic layer cannot be formed uniformly in the surface.

[0140] (Second embodiment)

[0141] Figure 8 It is a cross-sectional view schematically showing the structure of a developing processing apparatus 1 a according to the second embodiment.

[0142] Figure 8 The developing device 1a is omitted Figure 2The mixed - liquid supply nozzle 38 of the developing processing apparatus 1 of the first - grade first embodiment. In the developing processing apparatus 1 of the first embodiment, two types of rinsing liquids, DIW and a rinsing liquid containing a surfactant, are used. However, in the developing processing apparatus 1a, only one type of rinsing liquid, DIW, is used.

[0143] Next, an example of the developing process in the developing processing apparatus 1a will be described using Figure 9 as an illustration. Figure 9 It is a graph showing the wafer rotation speed at each time point in the cleaning process and the subsequent developing process.

[0144] It should be noted that hereinafter, only the parts of the developing process in the developing processing apparatus 1a that are different from Figure 2 the developing process in the developing processing apparatus 1, etc., will be described. Specifically, only the rinsing process will be described.

[0145] In the developing process of the developing processing apparatus 1a, after sequentially performing the developing - liquid pooling formation process of the aforementioned step S1, the stationary developing process of step S2, the cleaning process of step S3, and the hydrophilic - layer formation process of step S4, the following rinsing process (step S10) is performed.

[0146] (Step S10: Rinsing process)

[0147] In the rinsing process of step S10, after the hydrophilic - layer formation process of step S4, a rinsing liquid is supplied to the rotating wafer W to clean the wafer W. This rinsing process, as Figure 9 shown, includes a rinsing - liquid supply process (step S10a) and a drying process (step S10b). Moreover, the drying process includes a first drying process (step S10b1) and a second drying process (step S10b2).

[0148] (Step S10a: Rinsing - liquid supply process)

[0149] The rinsing - liquid supply process of step S10a is a process of supplying a rinsing liquid to the wafer W having a hydrophilic layer formed thereon while rotating the wafer W. Specifically, for the rotating wafer W, DIW as the rinsing liquid is supplied from the DIW supply nozzle 36. In this process, the wafer rotation speed is maintained at, for example, the same speed as in the rotation - maintaining process of step S4b (e.g., 1000 - 2000 rpm). After a preset time has elapsed since the start of the rinsing - liquid supply, the supply of the rinsing liquid from the DIW supply nozzle 36 is stopped, and instead, the gas supply nozzle 39 moves above the central part of the wafer W.

[0150] (Step S10b: Drying process)

[0151] The drying process of step S10b is a process of rotating the wafer in a state where no rinsing liquid is supplied after the rinsing liquid supply process of step S10a. Through this process, the rinsing liquid on the wafer W is dried.

[0152] (Step S10b1: First drying process)

[0153] Then, in the first drying process of step S10b1, which is the initial process of the drying process, similar to the first drying process of the aforementioned step S5b1, in the central portion of the wafer W, while supplying gas to form a concave portion in the DIW film and accelerating the rotation speed of the wafer, the concave portion is expanded (step S10b1). In this process, for the rotation speed of the wafer, for example, it is accelerated from the rotation speed of the wafer in the rinsing liquid supply process (e.g., 1000 - 2000 rpm) to the highest rotation speed HRS2 in this process (e.g., 1500 rpm or more), and then, it is maintained at this highest rotation speed HRS2 for a preset time. It should be noted that in this process, the rotation speed of the wafer can be accelerated to the highest rotation speed HRS2 at a constant acceleration or can be accelerated step by step.

[0154] It should be noted that at the end of the first drying process, the gas supply is stopped, and the gas supply nozzle 39 retracts outside the cup 22. In addition, the position of the gas supply nozzle 39 in this process is fixed above the central portion of the wafer W.

[0155] (Step S10b2: Second drying process)

[0156] After the first drying process, similar to the second drying process of the aforementioned step S5b2, as the concave portion of the DIW film formed on the wafer W expands, the rotation speed of the wafer is decelerated to a preset rotation speed RS (step S10b2). In this process, the rotation speed of the wafer is preferably decelerated to 800 rpm or more and 1800 rpm or less, and more preferably decelerated to 800 rpm or more and 1500 rpm or less. After deceleration, the rotation speed of the wafer is maintained at this rotation speed RS for a preset time, and then, the rotation of the wafer W is stopped.

[0157] It should be noted that the deceleration of the rotation speed of the wafer in the second drying process is carried out at a constant deceleration or can be carried out step by step.

[0158] In this embodiment, the supply of the rinsing liquid containing a surfactant is not carried out, but similar to the first embodiment, when a resist film with a large contact angle with water is formed on the wafer W, a hydrophilic layer can also be formed on the wafer W, and the contact angle of the wafer W with water becomes lower. Therefore, in this embodiment, it also becomes less likely to generate liquid removal of the rinsing liquid when rotating and drying the wafer, and it is less likely to generate defects.

[0159] In addition, in this embodiment, the deceleration process of step S3b is also performed, and the deceleration in this process is made smaller than the acceleration in the acceleration process of step S3a. Therefore, a hydrophilic layer is formed more uniformly within the wafer surface, and liquid removal during rinsing can be suppressed. As a result, defects can be reduced.

[0160] In addition, in this embodiment, the drying process of step S10, which is the same as the drying process of step S5b, is performed. Therefore, the risk of the generation of a large amount of remaining rinse liquid can be reduced. Furthermore, when the resist pattern is a line / space pattern, the occurrence of pattern collapse can be prevented. Additionally, in this embodiment, after the concave portion expands outward to a certain extent, the rotation speed is decelerated so that the force on the pattern near the interface between the concave portion and its outside does not become excessive, and thus pattern collapse is not likely to occur.

[0161] In the above description, the resist pattern is a line / space pattern. However, the above embodiments can also be applied to other resist patterns such as hole patterns.

[0162] In addition, in the above, as the developing method, the following stationary developing method is adopted: After forming a pool of the developing solution, the supply of the developing solution and the rotation of the wafer W are stopped. The technology of the present disclosure can also be applied to a rotating developing method (also referred to as non-pool developing) in which the wafer W is rotated while continuously supplying the developing solution.

[0163] It should be noted that in the above description, DIW is used as the aqueous cleaning liquid and the first rinse liquid, i.e., the aqueous rinse liquid. However, as the aqueous cleaning liquid and the aqueous rinse liquid, pure water can be used, and in addition, those obtained by adding some other substances to pure water can also be used as long as the main component is water (for example, the water content is 50% by mass or more).

[0164] The embodiments disclosed this time are examples in all aspects and should be considered not to be restrictive. The above embodiments can be omitted, replaced, and changed in various forms without departing from the appended claims and their gist.

[0165] It should be noted that the following configurations also fall within the protection scope of the present disclosure.

[0166] (1) A developing method, which is a developing method for developing a resist film on a substrate, and includes the following steps:

[0167] Step (A), supplying a developing solution to the aforementioned substrate to develop the aforementioned resist film and form a resist pattern;

[0168] Step (B), supplying an aqueous cleaning liquid to the developed aforementioned substrate and cleaning the substrate with the aqueous cleaning liquid;

[0169] Step (C): applying an aqueous solution of a water-soluble polymer onto the substrate cleaned with the aqueous cleaning liquid described above to form a hydrophilic layer having hydrophilicity on the surface of the substrate; and,

[0170] Step (D): cleaning the substrate having the hydrophilic layer formed thereon with a rinsing liquid,

[0171] The aforementioned step (B) includes the following steps:

[0172] Step (a): accelerating the rotation speed of the aforementioned substrate; and,

[0173] Step (b): after the aforementioned step (a) and until the start of the aforementioned step (C), decelerating the rotation speed of the aforementioned substrate,

[0174] The deceleration rate in the aforementioned step (b) is less than the acceleration rate in the aforementioned step (a).

[0175] According to the above (1), when forming a resist film with a large water contact angle on the substrate and rotating the substrate to discharge and dry the rinsing liquid, it becomes less likely to generate drainage of the rinsing liquid, that is, the rinsing liquid is less likely to remain on the substrate. Therefore, it is less likely to generate defects caused by the rinsing liquid remaining on the substrate.

[0176] In addition, a hydrophilic layer can be formed more uniformly within the substrate surface, and drainage during rinsing can be suppressed. As a result, defects can be reduced.

[0177] (2) The developing method according to the above (1), wherein,

[0178] The aforementioned step (D) includes the following steps:

[0179] Step (c): while supplying the aforementioned rinsing liquid to the substrate having the hydrophilic layer formed thereon, rotating the substrate; and,

[0180] Step (d): after the aforementioned step (c), rotating and drying the aforementioned substrate in a state where the aforementioned rinsing liquid is not supplied,

[0181] The aforementioned step (d) includes the following steps:

[0182] Step (m): while supplying gas to the center of the substrate to form a concave portion in the film of the aforementioned rinsing liquid, accelerating the rotation speed of the aforementioned substrate to expand the aforementioned concave portion; and,

[0183] Step (n): after the aforementioned step (m), decelerating the rotation speed of the aforementioned substrate as the aforementioned concave portion expands.

[0184] According to the above (2), the risk of the generation of a large amount of residual rinse liquid can be reduced. Furthermore, in the case where the resist pattern is a line / space pattern, the occurrence of pattern collapse can be prevented. Additionally, according to the above (2), after the concave portion expands outward to a certain extent, the rotation speed is decelerated so that the force on the pattern near the interface between the concave portion and its outside does not become excessive, and thus pattern collapse is not likely to occur.

[0185] (3) The developing method according to the above (2), wherein

[0186] the maximum rotation speed of the above-mentioned substrate in the above-mentioned step (m) is 700 rpm or more and 1800 rpm or less,

[0187] the above-mentioned step (n) is as follows: the rotation speed of the above-mentioned substrate is decelerated from the maximum rotation speed of the above-mentioned substrate in the above-mentioned step (m) to a preset rotation speed of 600 rpm or more.

[0188] (4) The developing method according to the above (2) or (3), wherein

[0189] the above-mentioned step (c) in the above-mentioned step (D) includes the following steps:

[0190] Step (x), while supplying an aqueous rinse liquid to the substrate on which the above-mentioned hydrophilic layer is formed, rotating the substrate; and,

[0191] Step (y), after the above-mentioned step (x), while supplying a rinse liquid containing a surfactant to the above-mentioned substrate, rotating the substrate,

[0192] in the above-mentioned step (x), the above-mentioned substrate is rotated at a preset rotation speed, then the rotation speed of the above-mentioned substrate is decelerated until the end of the above-mentioned step (x), and the rotation speed at the start of the above-mentioned step (y) is set to be lower than the maximum rotation speed in the above-mentioned step (m).

[0193] According to the above (4), the supply can be switched to a rinse liquid containing a surfactant with a low surface tension while maintaining the covering state under the aqueous rinse liquid unchanged.

[0194] (5) The developing method according to any one of the above (1) to (4), wherein

[0195] the above-mentioned step (C) includes the following steps:

[0196] Step (e), while supplying an aqueous solution of the above-mentioned water-soluble polymer to the above-mentioned substrate cleaned with the above-mentioned aqueous cleaning liquid, rotating the substrate; and,

[0197] Step (f), after the above-mentioned step (e), rotating the above-mentioned substrate in a state where the aqueous solution of the above-mentioned water-soluble polymer is not supplied.

[0198] According to the foregoing (5), the risk of the water-soluble polymer remaining as a residue can be reduced. In addition, in order to prevent the occurrence of retreat, a hydrophilic layer can be uniformly formed within the substrate surface. Furthermore, pattern refinement when adjusting the aqueous solution of the water-soluble polymer to be acidic can be prevented.

[0199] (6) The developing method according to any one of the foregoing (1) to (5), wherein the supply time of the aqueous cleaning liquid in the foregoing step (B) is longer than the supply time of the aqueous solution of the water-soluble polymer in the foregoing step (C).

[0200] According to the foregoing (6), the risk of the water-soluble polymer remaining as a residue and the risk of pattern refinement when the aqueous solution of the water-soluble polymer becomes acidic do not increase. In addition, by extending the supply time of the aqueous cleaning liquid, the entire substrate can be covered with a liquid film of the aqueous cleaning liquid having low reactivity with other liquids for the subsequent process.

[0201] (7) The developing method according to any one of the foregoing (1) to (6), wherein the time from the stop of the supply of the aqueous cleaning liquid in the foregoing step (B) to the start of the supply of the aqueous solution of the water-soluble polymer in the foregoing step (C) is 0.7 seconds or less.

[0202] (8) The developing method according to any one of the foregoing (1) to (7), wherein the maximum rotation speed of the foregoing substrate in the foregoing (a) step of the foregoing step (B) is 700 rpm or more and 1800 rpm or less.

[0203] (9) A developing apparatus for developing a resist film on a substrate, the developing apparatus comprising:

[0204] A substrate holding part for holding the foregoing substrate;

[0205] A rotation mechanism for rotating the foregoing substrate holding part;

[0206] A developing solution supply nozzle for supplying a developing solution to the foregoing substrate held by the foregoing substrate holding part;

[0207] An aqueous cleaning liquid supply nozzle for supplying an aqueous cleaning liquid to the foregoing substrate held by the foregoing substrate holding part;

[0208] An aqueous solution supply nozzle for supplying an aqueous solution of a water-soluble polymer to the foregoing substrate held by the foregoing substrate holding part;

[0209] A rinsing liquid supply nozzle for supplying a rinsing liquid to the foregoing substrate held by the foregoing substrate holding part;

[0210] A moving mechanism for moving the aforementioned developer supply nozzle, the aforementioned aqueous cleaning liquid supply nozzle, the aforementioned aqueous solution supply nozzle, and the aforementioned rinsing liquid supply nozzle; and,

[0211] A control unit configured to control the aforementioned rotation mechanism, the supply from the aforementioned developer supply nozzle, the supply from the aforementioned aqueous cleaning liquid supply nozzle, the supply from the aforementioned aqueous solution supply nozzle, the supply from the aforementioned rinsing liquid supply nozzle, and the aforementioned moving mechanism,

[0212] The aforementioned control unit is configured to perform control in the following manner:

[0213] Execute

[0214] Process (A): Supply a developer to the aforementioned substrate to develop the aforementioned resist film and form a resist pattern;

[0215] Process (B): Supply an aqueous cleaning liquid to the developed aforementioned substrate and clean the substrate with the aqueous cleaning liquid;

[0216] Process (C): Coat an aqueous solution of a water-soluble polymer on the aforementioned substrate that has been cleaned with the aforementioned aqueous cleaning liquid, and form a hydrophilic layer having hydrophilicity on the surface of the aforementioned substrate; and,

[0217] Process (D): Clean the substrate on which the aforementioned hydrophilic layer has been formed with a rinsing liquid,

[0218] In the aforementioned process (B), execute

[0219] Process (a): Accelerate the rotation speed of the aforementioned substrate; and,

[0220] Process (b): After the aforementioned process (a) and until the start of the aforementioned process (C), decelerate the rotation speed of the aforementioned substrate,

[0221] Make the deceleration rate in the aforementioned process (b) less than the acceleration rate in the aforementioned process (a).

[0222] (10) The developing processing apparatus according to the aforementioned (9), wherein,

[0223] There is a gas supply nozzle for supplying gas to the aforementioned substrate held by the aforementioned substrate holding portion,

[0224] The aforementioned moving mechanism moves the aforementioned gas supply nozzle,

[0225] The aforementioned control unit is configured to control the supply from the aforementioned gas supply nozzle, and

[0226] Is configured to perform control in the following manner:

[0227] In the aforementioned process (D), execute

[0228] Step (c), while supplying the rinsing liquid to the substrate having the hydrophilic layer formed thereon, rotating the substrate; and,

[0229] Step (d), after the step (c), rotating and drying the substrate without supplying the rinsing liquid,

[0230] In the step (d), the following is performed

[0231] Step (m), while supplying gas to the center of the substrate to form a recess in the film of the rinsing liquid, accelerating the rotational speed of the substrate to expand the recess; and,

[0232] Step (n), after the step (m), decelerating the rotational speed of the substrate as the recess expands.

[0233] (11) The developing processing apparatus according to the above (10), wherein,

[0234] The control unit is configured to perform control in the following manner:

[0235] In the step (c) of the step (D), the following is performed

[0236] Step (x), while supplying an aqueous rinsing liquid to the substrate having the hydrophilic layer formed thereon, rotating the substrate; and,

[0237] Step (y), after the step (x), while supplying a rinsing liquid containing a surfactant to the substrate, rotating the substrate,

[0238] In the step (x), the substrate is rotated at a preset rotational speed, then the rotational speed of the substrate is decelerated until the end of the step (x), and the rotational speed at the start of the step (y) is set to be lower than the maximum rotational speed in the step (m).

Claims

1. A developing process, which is a developing process for developing a resist film on a substrate, and includes the following steps: Step (A), supplying a developing solution to the substrate to develop the resist film and form a resist pattern; Step (B), supplying an aqueous cleaning solution to the developed substrate and cleaning the substrate with the aqueous cleaning solution; Step (C), coating an aqueous solution of a water-soluble polymer on the substrate cleaned with the aqueous cleaning solution to form a hydrophilic layer having hydrophilicity on the surface of the substrate; and, Step (D), cleaning the substrate having the hydrophilic layer formed thereon with a rinsing solution, The step (B) includes the following steps: Step (a), accelerating the rotation speed of the substrate; and, Step (b), after the step (a) and until the start of the step (C), decelerating the rotation speed of the substrate, The deceleration rate in the step (b) is less than the acceleration rate in the step (a), The step (D) includes the following steps: Step (c), rotating the substrate while supplying the rinsing solution to the substrate having the hydrophilic layer formed thereon; and, Step (d), after the step (c), rotating and drying the substrate in a state where the rinsing solution is not supplied, The step (d) includes the following steps: Step (m), accelerating the rotation speed of the substrate while supplying gas to the center of the substrate to form a recess in the film of the rinsing solution and expanding the recess; and, Step (n), after the step (m), decelerating the rotation speed of the substrate as the recess expands.

2. The developing process according to claim 1, wherein, The maximum rotation speed of the substrate in the step (m) is 700 rpm or more and 1800 rpm or less, The step (n) is as follows: decelerating the rotation speed of the substrate from the maximum rotation speed of the substrate in the step (m) to a preset rotation speed of 600 rpm or more.

3. The developing process according to claim 1, wherein, The step (c) of the step (D) includes the following steps: Step (x), rotating the substrate while supplying an aqueous rinsing solution to the substrate having the hydrophilic layer formed thereon; and, Step (y), after the step (x), rotating the substrate while supplying a rinsing solution containing a surfactant to the substrate, In the step (x), the substrate is rotated at a preset rotation speed, and then the rotation speed of the substrate is decelerated until the end of the step (x), and the rotation speed at the start of the step (y) is set to be lower than the maximum rotation speed in the step (m).

4. The developing process according to claim 2, wherein, The step (c) of the step (D) includes the following steps: Step (x), rotating the substrate while supplying an aqueous rinsing solution to the substrate having the hydrophilic layer formed thereon; and, Step (y), after the step (x), rotating the substrate while supplying a rinsing solution containing a surfactant to the substrate, In the process (x), the substrate is rotated at a preset rotational speed, and then the rotational speed of the substrate is decelerated until the end of the process (x), and the rotational speed at the start of the process (y) is set to be lower than the maximum rotational speed in the process (m).

5. The developing method according to claim 1, wherein the process (C) includes the following processes: Process (e), while supplying an aqueous solution of the water-soluble polymer to the substrate cleaned with the aqueous cleaning liquid, rotating the substrate; and, Process (f), after the process (e), rotating the substrate in a state where the aqueous solution of the water-soluble polymer is not supplied.

6. A developing method, which is a developing method for developing a resist film on a substrate, and includes the following processes: Process (A), supplying a developer to the substrate to develop the resist film and form a resist pattern; Process (B), supplying an aqueous cleaning liquid to the developed substrate and cleaning the substrate with the aqueous cleaning liquid; Process (C), coating an aqueous solution of a water-soluble polymer on the substrate cleaned with the aqueous cleaning liquid to form a hydrophilic layer having hydrophilicity on the surface of the substrate; and, Process (D), cleaning the substrate formed with the hydrophilic layer with a rinsing liquid, the process (B) includes the following processes: Process (a), accelerating the rotational speed of the substrate; and, Process (b), after the process (a), until the start of the process (C), decelerating the rotational speed of the substrate, the deceleration rate in the process (b) is less than the acceleration rate in the process (a), the process (C) includes the following processes: Process (e), while supplying an aqueous solution of the water-soluble polymer to the substrate cleaned with the aqueous cleaning liquid, rotating the substrate; and, Process (f), after the process (e), rotating the substrate in a state where the aqueous solution of the water-soluble polymer is not supplied.

7. The developing method according to any one of claims 1 to 6, wherein the supply time of the aqueous cleaning liquid in the process (B) is longer than the supply time of the aqueous solution of the water-soluble polymer in the process (C).

8. The developing method according to any one of claims 1 to 6, wherein the time from the stop of the supply of the aqueous cleaning liquid in the process (B) to the start of the supply of the aqueous solution of the water-soluble polymer in the process (C) is 0.7 seconds or less.

9. The developing method according to any one of claims 1 to 6, wherein the maximum rotational speed of the substrate in the process (a) of the process (B) is 700 rpm or more and 1800 rpm or less.

10. A developing apparatus, which is a developing apparatus for developing a resist film on a substrate, and includes: a substrate holding unit for holding the substrate; a rotation mechanism for rotating the substrate holding unit; a developer supply nozzle for supplying a developer to the substrate held by the substrate holding unit; A water-based cleaning liquid supply nozzle for supplying a water-based cleaning liquid to the substrate held by the substrate holding unit; An aqueous solution supply nozzle for supplying an aqueous solution of a water-soluble polymer to the substrate held by the substrate holding unit; A rinse liquid supply nozzle for supplying a rinse liquid to the substrate held by the substrate holding unit; A moving mechanism for moving the developer supply nozzle, the water-based cleaning liquid supply nozzle, the aqueous solution supply nozzle, and the rinse liquid supply nozzle; And, A control unit configured to control the rotation mechanism, the supply from the developer supply nozzle, the supply from the water-based cleaning liquid supply nozzle, the supply from the aqueous solution supply nozzle, the supply from the rinse liquid supply nozzle, and the moving mechanism, The control unit is configured to perform the following control: Execute Process (A), supplying a developer to the substrate to develop the resist film to form a resist pattern; Process (B), supplying a water-based cleaning liquid to the developed substrate and cleaning the substrate with the water-based cleaning liquid; Process (C), coating an aqueous solution of a water-soluble polymer on the substrate cleaned with the water-based cleaning liquid to form a hydrophilic layer having hydrophilicity on the surface of the substrate; and, Process (D), cleaning the substrate having the hydrophilic layer formed thereon with a rinse liquid, In the process (B), execute Process (a), accelerating the rotation speed of the substrate; And, Process (b), after the process (a) and until the start of the process (C), decelerating the rotation speed of the substrate, Making the deceleration rate in the process (b) less than the acceleration rate in the process (a), The developing processing apparatus has a gas supply nozzle for supplying a gas to the substrate held by the substrate holding unit, The moving mechanism moves the gas supply nozzle, The control unit is configured to control the supply from the gas supply nozzle, and Is configured to perform the following control: In the process (D), execute Process (c), rotating the substrate while supplying the rinse liquid to the substrate having the hydrophilic layer formed thereon; And, Process (d), after the process (c), rotating the substrate in a state where the rinse liquid is not supplied and drying it, In the process (d), execute Process (m), while supplying gas to the center of the substrate to form a recess in the film of the rinse liquid, accelerating the rotation speed of the substrate to expand the recess; and, Process (n), after the process (m), decelerating the rotation speed of the substrate as the recess expands.

11. A developing processing apparatus for developing a resist film on a substrate, comprising: A substrate holding unit for holding the substrate; A rotation mechanism for rotating the substrate holding unit; A developer supply nozzle for supplying a developer to the substrate held by the substrate holding unit; A water-based cleaning liquid supply nozzle for supplying a water-based cleaning liquid to the substrate held by the substrate holding unit; An aqueous solution supply nozzle for supplying an aqueous solution of a water-soluble polymer to the substrate held by the substrate holding unit; A rinse liquid supply nozzle for supplying a rinse liquid to the substrate held by the substrate holding unit; A moving mechanism for moving the developer supply nozzle, the aqueous cleaning liquid supply nozzle, the aqueous solution supply nozzle, and the rinse liquid supply nozzle; and, A control unit configured to control the rotation mechanism, the supply from the developer supply nozzle, the supply from the aqueous cleaning liquid supply nozzle, the supply from the aqueous solution supply nozzle, the supply from the rinse liquid supply nozzle, and the moving mechanism; The control unit is configured to perform control in the following manner: Execute Process (A): Supply a developer to the substrate to develop the resist film and form a resist pattern; Process (B): Supply an aqueous cleaning liquid to the developed substrate and clean the substrate with the aqueous cleaning liquid; Process (C): Coat an aqueous solution of a water-soluble polymer on the substrate cleaned with the aqueous cleaning liquid to form a hydrophilic layer having hydrophilicity on the surface of the substrate; and, Process (D): Clean the substrate having the hydrophilic layer formed thereon with a rinse liquid; In the process (B), execute Process (a): Accelerate the rotation speed of the substrate; and, Process (b): After the process (a) and until the start of the process (C), decelerate the rotation speed of the substrate, Make the deceleration rate in the process (b) less than the acceleration rate in the process (a); In the process (C), execute Process (e): Rotate the substrate while supplying the aqueous solution of the water-soluble polymer to the substrate cleaned with the aqueous cleaning liquid; and, Process (f): After the process (e), rotate the substrate in a state where the aqueous solution of the water-soluble polymer is not supplied.

12. The developing processing apparatus according to claim 10, wherein The control unit is configured to perform control in the following manner: In the process (c) of the process (D), execute Process (x): Rotate the substrate while supplying an aqueous rinse liquid to the substrate having the hydrophilic layer formed thereon; and, Process (y): After the process (x), rotate the substrate while supplying a rinse liquid containing a surfactant to the substrate, In the process (x), rotate the substrate at a preset rotation speed, then decelerate the rotation speed of the substrate until the end of the process (x), and set the rotation speed at the start of the process (y) to be lower than the maximum rotation speed in the process (m).

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