JP5018388B2 - Coating, developing device, coating, developing method and storage medium - Google Patents

Description

  The present invention relates to a coating, a developing apparatus, a coating, a developing method, and a storage medium that apply a resist to the surface of a substrate and develop the resist after exposure.

  In the photoresist process, which is one of the semiconductor manufacturing processes, for example, a chemically amplified resist is applied to the surface of a semiconductor wafer (hereinafter referred to as a wafer), the resist is exposed in a predetermined pattern, and a developer is supplied Thus, a resist mask is obtained by forming a resist pattern. Such processing is generally performed using a system in which an exposure apparatus is connected to a coating / developing apparatus for coating and developing a resist.

  In recent years, immersion exposure may be performed as the exposure process in order to achieve a finer resist pattern. Briefly describing the immersion exposure, as shown in FIG. 16A, a liquid film 103 made of a liquid that transmits light, such as pure water, is formed between the exposure lens 102 of the exposure means 101 and the wafer W, and As shown in FIG. 16B, the exposure unit 101 is moved in the horizontal direction, the exposure unit 101 is arranged at a position corresponding to the next transfer region (shot region) 104, and the light irradiation operation is repeated. In this exposure method, a predetermined circuit pattern is transferred to the resist film 105. In the figure, reference numerals 106 and 107 denote a liquid supply path and a drainage path for forming the liquid film 103, respectively. In the drawing, the transfer region 104 is shown larger than the actual size. Further, in order to protect the resist film before immersion exposure, a water-repellent protective film that is removed before or during development may be formed on the surface of the resist film.

  By the way, in the lithography process as described above, when a resist residue and a protective film are formed on the resist film surface after development, a residual defect occurs in which the protective film residue remains in addition to the resist film surface. There is. This residual defect largely depends on the pattern type to be formed in the resist film such as contact holes and line spaces and the opening ratio of the resist film, and also depends on the material constituting the resist film. Residual defects are likely to occur, and in particular, when the liquid immersion exposure is performed without forming the protective film, many residual defects are generated.

  Usually, after supplying a developing solution to a wafer, pure water is supplied to the wafer to wash away the developing solution, and then the wafer is rotated at a high speed around the vertical axis, and the pure water is shaken off to perform a drying process. . The residue defects can be reduced to some extent by optimizing the conditions such as the discharge amount, discharge time, and processing temperature of the cleaning process using pure water after development, but it is difficult to completely remove the defects. Thus, it is not preferable because it takes time to detect the optimum condition and to set the condition. Although Patent Document 1 describes a method for suppressing the dissolution of a resist into a liquid layer formed during immersion exposure, the above problem cannot be solved.

JP 2005-294520 A

  The present invention has been made to solve such a problem, and its purpose is to generate a residue defect in which a residue is left attached to the resist surface of a substrate coated with a resist and developed after exposure. An object of the present invention is to provide a coating, developing apparatus, coating, developing method and storage medium that can be suppressed.

The coating and developing apparatus of the present invention includes a coating module for coating a resist on the surface of a substrate,
After the resist coating, the developer is supplied to form a pattern in the resist by developing the pre Symbol resist exposure surface of the substrate, then the cleaning liquid supply to remove the developer from the substrate A developing module for performing a drying process on the substrate to remove the cleaning liquid from the substrate ;
A chemical nozzle that increases the hydrophilicity of the resist surface without altering the resist, and supplies a chemical to the substrate to remove residues attached to the resist after the drying treatment;
It is provided with.

  The chemical liquid nozzle may be provided in a chemical liquid rinsing module separate from the developing module, and the chemical liquid rinsing module may include a substrate holding unit that holds a substrate when supplying the chemical liquid, or the chemical liquid nozzle The developing module may be provided. Moreover, you may provide the chemical | medical solution removal means which removes a chemical | medical solution from a board | substrate, In that case, the said chemical | medical solution removal means is equipped with the drying means for drying the chemical | medical solution supplied to the board | substrate, for example. Further, for example, the drying unit is a unit that rotates a substrate holding unit that holds the substrate in order to spin dry the substrate. For example, the said chemical | medical solution is alcohol, In that case, the said chemical | medical solution may contain the acid.

  Further, for example, a chemical solution storage unit that stores the chemical solution, an acidity detection unit that detects acidity in the chemical solution stored in the chemical solution storage unit, and a detection value of the acidity of the acidity detection unit are set in advance. And a means for controlling the supply of the acidic solution to the chemical solution reservoir so as to exceed the acidity, and the chemical solution supplied to the substrate is collected, particles in the chemical solution are removed, and the chemical solution nozzle is provided. You may provide the chemical | medical solution reproduction | regeneration means to supply. For example, the exposure process is an immersion exposure process in which a liquid layer that transmits light is formed on the surface of the resist, and the resist is a resist used for the immersion exposure process. A heating module for heating the substrate supplied with the chemical solution and drying the resist swollen with the chemical solution may be provided. The chemical liquid nozzle may have a discharge port that is opened in a slit shape, or may have a plurality of discharge ports arranged in a lateral direction, and moves while moving from one end side to the other end side of the substrate. You may discharge a chemical | medical solution to a board | substrate. Furthermore, an angle formed by the discharge direction of the chemical liquid discharged from the chemical liquid nozzle onto the substrate and the substrate is, for example, 15 degrees.

The coating and developing method of the present invention includes a step of applying a resist to the surface of a substrate, an exposure step of exposing the resist, and supplying a developer to the surface of the exposed substrate to form a pattern on the resist. A step of supplying a cleaning solution to the substrate supplied with the developer and removing the developer, a step of drying the substrate to remove the cleaning solution, and a step of removing the resist from the surface of the resist without altering the resist. A step of supplying the chemical solution to the chemical nozzle from the chemical solution storage portion storing the chemical solution for enhancing the hydrophilicity and removing the residue attached to the resist after the drying treatment, and holding the chemical solution from the chemical solution nozzle to the substrate holding portion And a step of discharging onto the substrate.

  The said chemical | medical solution is alcohol, for example, and may contain the acid. A step of detecting the acidity in the chemical solution stored in the chemical solution storage unit; and a step of controlling the supply of the acidic solution to the chemical solution storage unit so that the detected value of the acidity exceeds a preset acidity value; , May be provided. You may provide the process which collect | recovers the chemical | medical solution supplied to the board | substrate, removes the particle | grains in a chemical | medical solution, and supplies it to a chemical | medical solution nozzle. A step of heating the substrate supplied with the chemical solution and drying the resist swollen with the chemical solution may be provided.

  The storage medium of the present invention comprises a coating module for coating a resist on a substrate, and a development module for developing the resist by supplying a developing solution to the surface of the exposed substrate after resist coating, A storage medium storing a computer program used in a developing device, comprising a group of steps for carrying out the above-described coating and developing methods.

  In the present invention, a chemical solution is supplied to a substrate after development to improve the hydrophilicity of the resist surface without altering the resist of the substrate and to remove residues attached to the resist after the development treatment. As shown in Examples described later, the hydrophilicity of the resist surface is increased, so that residues remaining on the resist surface after development are easily removed from the resist surface, and the occurrence of residue defects can be suppressed.

  An overall configuration of a system in which an exposure apparatus is connected to a coating and developing apparatus according to an embodiment of the present invention will be briefly described with reference to FIGS. In FIG. 1 and FIG. 2, B1 is a carrier block for carrying in / out a substrate C, for example, 25 carriers C that are hermetically stored, and a carrier carrying-in portion 12 having a placing portion 11 on which a plurality of carriers C can be placed side by side. In addition, an opening / closing part 13 provided on the wall surface in front of the mounting part 11 and a transfer means A1 for taking out the wafer W from the carrier C via the opening / closing part 13 are provided.

  A processing block B2 surrounded by a housing 14 is connected to the back side of the carrier block B1. As shown in FIG. 3, the processing block B2 includes a shelf unit U1, U2, U3 in which heating / cooling modules are arranged in order from the front side, and a main transfer for transferring a wafer W between processing modules to be described later. Means A2 and A3 are alternately arranged. That is, the shelf units U1, U2, U3 and the main transfer means A2, A3 are arranged in a line in the front-rear direction as viewed from the carrier block B1, and an opening for transferring a wafer (not shown) is formed at each connection portion. The wafer W can freely move in the processing block B2 from the shelf unit U1 on one end side to the shelf unit U3 on the other end side.

  The main transport means A2 and A3 include one surface portion on the shelf unit U1, U2 and U3 side arranged in the front-rear direction when viewed from the carrier block B1, and one surface portion on the right liquid processing module U4 and U5 side which will be described later. , Which is placed in a space surrounded by a partition wall 15 composed of a rear surface portion that forms one side of the left side, and performs a cycle transport that sequentially moves between a series of preset modules. As a result, the wafers move in order. In the figure, reference numerals 16 and 17 denote temperature / humidity adjustment modules equipped with a temperature control device for chemicals used in each module, a duct for temperature / humidity adjustment, and the like.

  For example, as shown in FIG. 2, the liquid processing modules U4 and U5 are provided with a coating module COT, a developing module DEV, and an antireflection film on a storage portion 18 that forms a space for supplying a chemical liquid such as a coating liquid (resist liquid) and a developing liquid. The forming module BARC and the acidic alcohol rinsing module 3 are stacked in a plurality of stages, for example, five stages. The application module COT is a module for applying a resist to the wafer W, and the antireflection film forming module BARC is a module for applying a chemical solution for forming an antireflection film to the wafer W. The development module DEV supplies the developer to the wafer W to perform development processing. The acidic alcohol rinse module 3 will be described later.

  In addition, the shelf units U1, U2, and U3 described above are configured such that various modules for performing pre-processing and post-processing of the processing performed in the liquid processing modules U4 and U5 are stacked in a plurality of stages, for example, 10 stages. A heating module LHP for heating (baking) the wafer W, a cooling module CPL for cooling the wafer W, and the like are included. In the figure, TRS is a delivery module. The TRS of the shelf unit U1 has a role of delivering the wafer W between the carrier block B1 and the processing block B2, and the delivery module TRS of the shelf unit U3 is connected to the processing block B2. It has a role of delivering the wafer W to / from B3. Further, the shelf unit U1 includes a plurality of hydrophobic treatment modules ADH for performing a hydrophobic treatment on the wafer W, and the shelf unit U3 includes a plurality of PEBs that are heating modules for heating the wafer W after exposure.

  An exposure apparatus B4 is connected to the back side of the shelf unit U3 in the processing block B2 through an interface block B3 including, for example, a first transfer chamber 21 and a second transfer chamber 22. The first transfer chamber 21 and the second transfer chamber 22 are provided with transfer means A4 and A5 for transferring the wafer W between the processing block B2 and the exposure apparatus B4, respectively. In the chamber 21, a buffer module BM and a shelf unit U6 are respectively provided on the left and right of the transfer means A4 toward the exposure apparatus B4. A pure water rinse module I is provided in the second transfer chamber 22.

  The wafer transfer means A4 and A5 are configured to be rotatable about the vertical axis, movable up and down, and movable back and forth, and the wafer transfer means A4 is further configured to be movable along the guide 23 in the lateral direction. The shelf unit U6 is configured by vertically stacking a delivery module and, for example, a high-accuracy temperature control module (ICPL) having a cooling plate. The pure water rinsing module I is configured in the same manner as a substrate holding portion of the rinsing module 3 described later, and includes a substrate holding portion that is rotatable around a vertical axis and a pure water that discharges pure water to the wafer W held by the substrate holding portion. A water nozzle is provided, and pure water is supplied to the wafer W after immersion exposure to clean the wafer W, and then the substrate holder is rotated to shake off the pure water and dry the wafer W.

  The wafer transfer means A4 can access the modules of the shelf units U3 and U6 and the buffer module BM, and the wafer transfer means A5 is used for each stage of the exposure apparatus B4 described later, each module of the shelf unit U6, and the pure water rinse module I. Can be accessed. The place where the wafer is delivered is called a module.

  As described in the background art section, the exposure apparatus B4 is an apparatus that performs immersion exposure by forming a liquid film of pure water on the resist film surface, for example, and the wafer W carried from the interface block B3 is placed thereon. A carry-in stage 24 and a carry-out stage 25 on which the wafer W delivered to the interface block B3 is placed are provided.

  Next, the acidic alcohol rinse module 3 will be described with reference to FIGS. 4 and 5. 4 and 5 are a longitudinal side view and a transverse plan view of the module 3, respectively. In the figure, reference numeral 31 denotes a housing, and a transport port 33 that can be opened and closed by a shutter 32 is provided on a side wall of the housing 31. In the figure, reference numeral 34 denotes a spin chuck that forms a substrate holding unit, and is configured to hold the wafer W horizontally by vacuum suction. The spin chuck 34 can be rotated around a vertical axis by a driving unit 35 and can be moved up and down to deliver the wafer W to and from the main transfer means A3. The drive unit 35 serves as a drying means for performing spin drying that rotates the wafer W through the spin chuck 34 to shake off the chemical solution attached to the wafer W and dry the wafer W.

  A cup 36 is provided around the spin chuck 34 so as to surround a side portion extending from the wafer W to the spin chuck 34. The bottom portion of the cup 36 is partitioned into an outer portion 37A and an inner portion 37B that communicate with each other, and a drain port 38a is opened on the bottom surface of the outer portion 37A. One end of a chemical drainage pipe 38 is opened to the drainage port 38a, and the other end of the drainage pipe 38 is connected to an acidic alcohol supply unit 5 described later. An exhaust port 39a is opened, for example, in an annular shape on the bottom surface of the inner portion 37B, and one end of an exhaust pipe 39 is connected to the exhaust port 39a so that the exhaust in the cup 36 can be performed.

  The acidic alcohol rinsing module 3 includes a chemical nozzle 41 that discharges an acidic alcohol L, which will be described later, onto the wafer W to clean (rinse) the wafer W. The nozzle 41 has a circular discharge port 42 that opens vertically downward. It has. The diameter of the discharge port 42 indicated by L1 in FIG. 4 is 3 mm, for example. One end of a chemical solution supply pipe 43 is connected to the chemical solution nozzle 41, and the other end of the chemical solution supply pipe 43 is connected to the acidic alcohol supply unit 5 via a liquid supply device system 44 including a valve and a mass flow controller. Yes. The liquid supply device system 44 receives a control signal from the control unit 100 described later, and controls supply / disconnection of the acidic alcohol L, which is a chemical solution, from the chemical solution nozzle 41 to the wafer W.

  As shown in FIG. 5, the chemical nozzle 41 is connected to a drive unit 46 via an arm 45, and the drive unit 46 is locked to a guide rail 47 that extends horizontally in the horizontal direction, and moves along the guide rail 47. To do. The chemical nozzle 41 can move from the standby area 48 of the chemical nozzle 41 provided outside the cup 36 to the central portion of the wafer W in accordance with the movement of the driving unit 46 and supply the chemical solution to the central portion of the wafer W. It is like that.

  As will be described later, since acid is contained in the acidic alcohol L supplied to the wafer W as a chemical solution, each part in the housing 31 is preferably made of a highly acid-resistant material. For example, the chemical nozzle 41 is made of a highly acid-resistant resin such as PFA (tetrafluoroethylene), and when the arm 45 is made of metal, it is preferably made of a highly acid-resistant ceramic or SUS.

  Then, the structure of the acidic alcohol supply part 5 connected to the acidic alcohol rinse module 3 is demonstrated, also referring FIG. As shown in FIG. 2, the acidic alcohol supply unit 5 is provided outside the casing 14 of the coating and developing apparatus, for example, and includes an alcohol regeneration unit 4, an acidic alcohol storage tank 51 and an acidic solution storage tank 71 that form sealed containers, respectively. It has. The acidic alcohol storage tank 51 stores, for example, acidic alcohol L composed of 4-methyl 2-pentanol which is alcohol and acid, and this acidic alcohol L increases the hydrophilicity of the surface without altering the resist. Thus, it has a role of removing residues adhering to the resist after development processing from the resist surface. Under the liquid surface of the acidic alcohol L stored in the acidic alcohol storage tank 51, the other end of the chemical liquid supply pipe 43 whose one end is connected to the chemical liquid nozzle 41 is immersed. Further, the other end of the drainage pipe 38 whose one end is connected to the cup 36 is connected to the acidic alcohol storage tank 51 via the alcohol regeneration unit 4.

  For example, the alcohol regeneration unit 4 includes a filter that removes particles such as organic substances insoluble in the acidic alcohol L contained in the acidic alcohol L. The acidic alcohol L that is supplied from the acidic alcohol storage tank 51 to the chemical nozzle 41 and discharged from the nozzle 41 toward the wafer W and flows into the drain pipe 38 from the cup 36 is contained in the alcohol regeneration unit 4. Are removed and supplied to the acidic alcohol storage tank 51 for storage. Further, the alcohol regeneration unit 4 may be configured to remove the particles by distilling the acidic alcohol L.

  One end of the pressurizing gas supply pipe 61 is opened in the space above the surface of the acidic alcohol L stored in the acidic alcohol storage tank 51, and the other end of the pressurizing gas supply pipe 61 is a valve, a mass flow controller, or the like. It is connected to a supply source 63 of Ar (argon) gas, which is an inert gas, via a gas supply device system 62 that includes the gas. The gas supply device system 62 receives a control signal from the control unit 100 to control the supply / disconnection of Ar gas from the gas supply source 63 to the acidic alcohol storage tank 51, and from the gas supply source 63 to the acidic alcohol storage tank 51. When the Ar gas is supplied, the inside of the tank 51 is pressurized and the acidic alcohol L flows into the chemical solution supply pipe 43. The flow rate of the acidic alcohol L is controlled by the liquid supply device system 44, and the chemical solution nozzle 41 is supplied. To the wafer W.

  The acidic alcohol storage tank 51 is provided with an acidity monitor 64 made up of, for example, an oxidation-reduction potential (ORP) measuring device, and the detection unit 65 provided in the acidity monitor 64 is immersed below the surface of the acidic alcohol L. The redox potential of the acidic alcohol L is measured. The acidity monitor 64 transmits a signal corresponding to the oxidation-reduction potential measured by the detection unit 65 to the control unit 100, and the control unit 100 calculates the pH value of the acidic alcohol L based on the oxidation-reduction potential, for example. The calculated pH value is displayed on a display screen (not shown).

  One end of the acidic solution supply pipe 66 is immersed under the surface of the acidic alcohol L, and the other end of the acidic solution supply pipe 61 is filled with the acidic solution E stored in the acidic solution storage tank 71 through the valve V1. It is immersed under the liquid level. The acidic solution E will be described later. The opening and closing of the valve V1 is controlled by the control unit 100.

  In the acidic solution storage tank 71, one end of a pressurizing gas supply pipe 72 is opened in a space above the surface of the acidic solution E, and the other end of the pressurizing gas supply pipe 72 is a gas including a valve, a mass flow controller, and the like. It is connected to a supply source 74 of Ar (argon) gas, which is an inert gas, via a supply device system 73. The gas supply device system 73 receives a control signal from the control unit 100 and controls the supply / disconnection of Ar gas from the gas supply source 74 to the acidic solution storage tank 71.

The acidic solution E stored in the acidic solution storage tank 71 has a role of increasing the acidity of the acidic alcohol L in the acidic alcohol storage tank 51. For example, triphenylsulfonium used as an acid generator in each ArF resist, for example. Salts ((C ₆ H ₅ ) ₃ S ⁺ CF ₃ SO ₃ ⁻ ), o-nitrobenzyl ester (NO ₂ (C ₆ H ₅ ) CH ₂ S ₂ Ar), and trifluoromethanesulfonic acid soluble in alcohol (CF ₃ SO ₃ H) formed by a chemical solution containing a like.

  Next, the control unit 100 will be described. The control unit 100 is composed of a computer, for example, and has a program storage unit (not shown). The program storage unit stores a program made of software, for example, in which instructions are set so as to perform coating and development processing, which will be described later, and the program is read by the control unit 100 to control the program. As will be described later, the unit 100 controls the operation of each transfer means, the supply of chemicals to the wafer W in each liquid processing module, heating, heating of the wafer W in the cooling module, cooling processing, and the like. This program is stored in the program storage unit while being stored in a storage medium such as a hard disk, a compact disk, a magnetic optical disk, or a memory card.

  The control unit 100 includes an input screen, and an operator of the coating and developing apparatus can set an upper limit value and a lower limit value of the pH value of the acidic alcohol L from the input screen. The control unit 100 is acidic. Based on the signal from the degree monitor 64, it is determined whether the pH value of the acidic alcohol L in the acidic alcohol storage tank 51 is within the upper limit value and the lower limit value. The upper limit value and the lower limit value of the pH value are increased, for example, in order to increase the hydrophilicity of the resist surface so that the residue is effectively removed and not affect the pattern formed on the resist film. pH 6 and pH 4 are set.

  When the control unit 100 determines that the pH value of the acidic alcohol L is larger than the set upper limit value, the control unit 100 opens the valve V1 and uses the acidic solution storage tank 71 with Ar gas via the gas supply device system 73. The pressure inside is increased and the acidic solution E in the acidic solution storage tank 71 is supplied into the acidic alcohol storage tank 51 so that the detected acidity falls within the range between the above upper limit value and the lower limit value. Control. When it is determined that the pH of the acidic alcohol L is lower than the lower limit set by the control unit 100, an alarm is generated by an alarm generation mechanism (not shown), for example.

  Further, the liquid treatment modules and the pure water rinse module I of the shelf units U4 and U5 will be further described. The coating module COT, the antireflection film forming module BARC, and the development module DEV are also similar in housing and rotation to the acidic alcohol rinse module 3. A flexible substrate holding part, a cup and a nozzle for discharging a chemical used in each module are provided. In addition to the nozzle for supplying the developer, the developing module DEV is provided with a nozzle for supplying pure water to supply the pure water to the wafer W after the developer is supplied and developed to wash away the developer. ing.

  Next, the operation of the above-described coating and developing apparatus will be described with reference to the flowchart of FIG. First, when the carrier C storing the wafer W from the outside is placed on the placement unit 11, the lid of the carrier C is removed together with the opening / closing unit 13, and the wafer W is taken out by the transfer means A 1 of the carrier block B 1. The wafer W is transferred to the main transfer means A2 of the processing block B2 via a transfer module (not shown) of the shelf unit U1, and transferred to the hydrophobic processing module ADH of the shelf unit U1 by the main transfer means A2. After being subjected to the hydrophobization process, the film is transferred to the cooling module CPL of the shelf unit U1 or U2 and cooled, and then transferred to the coating module COT, where a resist coating process is performed to form a resist film (step S1). ). In addition, as a pre-process of the resist coating process, an anti-reflection film forming process may be performed by the anti-reflection film forming unit BARC instead of performing the hydrophobizing process by the hydrophobizing module ADH.

  The wafer W on which the resist film is formed is heated by the heating module LHP forming one shelf of the shelf units U1 to U3, and further cooled by the cooling module CPL forming one shelf of the shelf units U1 to U3. It is carried into the interface block B3 via the delivery module TRS of the unit U3. In this interface block B3, the wafer W is transferred from the buffer module BM to the high precision temperature control unit ICPL of the shelf unit U6 by the transfer means A4, and the wafer W whose temperature has been adjusted by the ICPL is transferred to the exposure apparatus B4 by the transfer means A5. It is conveyed to 24. Thereafter, the wafer W is transferred to a predetermined location in the exposure apparatus B4, and the immersion exposure process is performed on the resist film as described in the background art section (step S2).

  The wafer W after the immersion exposure processing is placed on the carry-out stage 25, and is transferred to the pure water rinse module I by the transfer means A5, where pure water is supplied to the surface, and the wafer W is rinsed (cleaned). The liquid remaining on the surface of the wafer W used for immersion exposure is removed. Subsequently, the wafer W rotates around the vertical axis at a high speed via a substrate holding unit (not shown) of the pure water rinse module I, and the pure water is shaken off from the wafer W and the wafer W is dried (step S3). ). The dried wafer W is transferred to the heating module PEB of the shelf unit U3 by the transfer means A5 and A4 and subjected to a heating process (step S4). Thereafter, the wafer W is transferred to the developing module DEV by the main transfer means A3. The Then, after a developing solution is supplied to the wafer W by the developing module DEV to dissolve unnecessary portions of the resist film and form a resist pattern (step S5), pure water is supplied to the wafer W. After the developer is washed away by the pure water and the entire surface of the wafer W is rinsed, the wafer W rotates at high speed around the vertical axis via the substrate holding portion of the DEV, and the pure water is shaken off from the wafer W. W is dried (step S6).

  When the wafer W is dried, the wafer W is transferred to the acidic alcohol rinse module 3 by the main transfer means A3. Hereinafter, the operation of the chemical solution nozzle 41 of the acidic alcohol rinsing module 3 and the state of the surface of the wafer W will be described with reference to FIGS. As shown in FIG. 9A, the residue D generated from the resist film R by the development process is attached to the surface of the resist film R on which the resist pattern R1 is formed. When the central portion of the back surface of the wafer W is held by the spin chuck 34, the chemical solution nozzle 41 moves from the standby region 48 to the center of the wafer W (FIG. 8A), and as shown in FIG. The wafer 34 is rotated about the vertical axis by the chuck 34, and the acidic alcohol L whose pH value is controlled to 4 to 6 as described above is supplied from the chemical nozzle 41 to the wafer W, and the center of the wafer W is caused by centrifugal force. The entire surface of the wafer W is rinsed from the portion to the peripheral portion.

  The surface of the resist film R to which the acidic alcohol L is supplied changes so as to increase the hydrophilicity as shown in the examples described later, whereby the affinity with the residue D is lowered, and the residue D becomes a resist film. Dissociates from the surface of R (FIGS. 9B and 9C). When a predetermined time elapses after discharging the acidic alcohol L, the discharging of the acidic alcohol L is stopped while the rotation of the wafer W is continued, and the acidic alcohol L including the residue D is shown in FIG. Thus, the wafer W is shaken off and the wafer W is dried (step S7). When a predetermined time elapses after the supply of the acidic alcohol L is stopped, the rotation of the wafer W is stopped, and the wafer W is unloaded from the acidic alcohol rinse module 3 by the main transfer means A3, and the main transfer means A3, A2 and the shelf unit U1, It is delivered to the transport means A1 via the delivery module TRS of U2, and returned to the original carrier C on the mounting table 11 by the transport means A1.

  According to the coating and developing apparatus described above, after developing the wafer W on which the resist film that has been subjected to immersion exposure by the developing module DEV is developed, acidic alcohol is used as a chemical solution from the chemical solution nozzle 41 of the acidic alcohol rinse module 3 as the wafer W. The wafer W is rinsed. As will be described later in the examples, the hydrophilicity of the resist surface is increased by such treatment, and the residue is prevented from remaining on the resist film surface, and this residue defect can be suppressed. Since the acidic alcohol that does not alter the resist is used, the influence of the resist pattern shape is suppressed. Moreover, as shown in the Example mentioned later, although the alcohol which does not contain an acid may be used as a chemical | medical solution used for the acidic alcohol rinse module 3, by using acidic alcohol like the above-mentioned embodiment, a residue defect is suppressed more. be able to.

  Depending on the constituent material of the chemical solution used in the acidic alcohol rinsing module 3 and the constituent material of the resist film, the chemical solution soaks into the resist film, and the resist film swells to cause the resist film to swell. As shown in FIG. 10A, the line width (CD) of the resist pattern R1 may be smaller than the desired line width and the uniformity of each part of the pattern R1 may be lowered. In that case, as shown in FIG. As described above, after performing Steps S1 to S7, the wafer W is heated by the heating modules LHP of the shelf units U1 and U2 and annealed (Step S8), and then returned to the carrier C. It may be. If annealing is performed in this manner, the chemical solution that has permeated into the resist film is evaporated to dry the resist film R, and control is performed so that the CD of the resist pattern R1 becomes large as shown in FIG. The uniformity of each part of the pattern R1 can be improved and a good pattern shape can be obtained. In addition, you may perform the heat processing by the heating module LHP in order to prevent that the wall of the resist which comprises a pattern collapses (pattern collapse) by removing a chemical | medical solution and drying a resist film.

  Further, for example, after forming a resist film, before the immersion exposure, a protective film for protecting the resist film is formed on the resist film surface, and after the immersion exposure, the protective film is removed and then development processing is performed. Then, the above-described acidic alcohol rinsing treatment may be performed. The protective film may be removed by dissolving in a developer. As an alcohol material constituting the chemical solution of the acidic alcohol rinsing module 3, in addition to 4-methyl-2-pentanol, for example, an alcohol used as a solvent for a material for forming these protective films has little influence on the resist. Therefore, it is preferably used.

  Instead of providing the chemical nozzle 41 in a dedicated housing as in the above-described embodiment, the chemical nozzle 41 may be provided in the developing module DEV. FIG. 12 shows an example. In the figure, the same components as those of the acidic alcohol rinsing module 3 are denoted by the same reference numerals. In the figure, 76 is a developer discharge nozzle, and 77 in the figure is a developer supply source connected to the developer discharge nozzle 76. Similarly to the chemical nozzle 41, the developer discharge nozzle 76 moves from the outside of the cup 36 to the center of the wafer W, and can discharge the developer to the center. Such a developing module DEV may be formed, and the acidic alcohol rinsing process in step S7 may be performed after the developing process in step S5 without performing the rinsing with pure water and the drying process in step S6 described above. Even when the treatment is performed in such a procedure, the annealing treatment may be performed as necessary.

  The acidic alcohol supply unit 5 is provided outside the coating and developing apparatus in the above-described embodiment, but may be provided inside the coating and developing apparatus. The acidity monitor 64 is configured using a pH meter or the like that can directly measure the pH of the chemical solution in the acidic alcohol storage tank 51 instead of the oxidation-reduction potential measuring device, and corresponds to the pH measured from the pH meter. A signal to be transmitted may be transmitted to the control unit 100.

  The shape of the chemical nozzle of the chemical rinsing module is such that the chemical can be supplied with high uniformity to the resist, and its impact is reduced when the chemical is supplied to the wafer W as will be described later. Is preferably selected, and is not limited to the configuration including the circular discharge port described above. For example, as shown in FIG. 13A, a chemical nozzle 81 having a slit-like discharge port 82 opened at the lower end surface may be used. For example, in the chemical nozzle 81, as shown in FIGS. 13B and 13C, the discharge port 82 is arranged on the diameter of the wafer W, and the chemical liquid is discharged onto the diameter and the wafer W is rotated to rotate the entire wafer W. Supply chemicals to Alternatively, the chemical liquid nozzle 81 may be moved from one end side to the other end side of the wafer W to supply the chemical liquid. When the diameter of the wafer W is 20 mm, the size of the lower end surface of the nozzle 82 indicated by L2 and L3 in FIG. 13A and the size of the discharge port 82 in the length direction are, for example, 20 mm and 18 mm, respectively. is there.

  Instead of forming the discharge ports 82 in the form of slits in the chemical liquid nozzle 81, for example, a plurality of circular discharge ports 83 may be arranged along the length direction of the nozzles as shown in FIG. When the diameter of the wafer W is 20 mm, the size in the length direction of the lower end surface of the chemical liquid nozzle 81 indicated by L4 and L5 in FIG. 13D and the diameter of each discharge port 83 are 20 mm and 2 mm, for example. is there.

  By the way, when the chemical liquid is discharged onto the wafer W by the acidic alcohol rinsing module 3, the chemical liquid discharged onto the wafer W is scattered and adheres to a location away from the supplied position on the wafer W. In order to suppress a decrease in processing uniformity in the film and a decrease in defect removal performance and CD uniformity, it is preferable to suppress the impact of the chemical solution on the wafer W. In order to suppress such an impact, it is effective to appropriately set the discharge position and discharge direction of the chemical liquid from the chemical nozzle to the wafer W in addition to appropriately forming the shape of the nozzle as described above. FIG. 14A shows an example of a chemical nozzle configured so that the discharge position and the discharge direction can be freely set. The chemical nozzle 87 is configured in the same manner as the chemical nozzle 41, and is attached to and supported by the arm 45 via connection portions 85 and 86. The connecting portion 85 can freely set the height position from the wafer W at the tip of the arm 45.

  The connecting portion 86 can be slid at the position along the extending direction of the arm 45 with respect to the connecting portion 85, and the chemical solution nozzle 87 can be freely attached to the connecting portion 86 at an angle around the horizontal axis. Be able to. Accordingly, for example, as shown by a solid line in FIG. 14A, a chemical nozzle 87 is attached to the arm 45, and the angle θ formed by the surface of the wafer W and the discharge direction of the chemical shown by the chain line is reduced to suppress the impact. it can.

  Further, as shown in FIG. 14B, the connecting portion 86 is configured such that the angle of the connecting portion 85 can be freely set around the vertical axis with respect to the connecting portion 85, and along the forward or reverse direction of the rotation of the wafer W. It may be possible to supply a chemical solution. Further, for example, the chemical solution may be supplied through the driving unit 46 connected to the arm 45 while sliding the chemical nozzle 41 along the radial direction of the wafer W as shown in FIG.

  Further, for example, in the chemical liquid nozzle 81 provided with the slit-like discharge port 82 shown in FIG. 13A, the slit length L3 may be configured to be the same size as the diameter of the wafer W. Further, in the chemical liquid nozzle 81 having the plurality of discharge ports 83 shown in FIG. 13D, the distance L6 from the discharge port 83 at one end to the discharge port 83 at the other end in the nozzle length direction is the diameter of the wafer W. The chemical solution may be supplied to the entire diameter of the wafer W. Even when the nozzle 81 having the discharge port is used as described above, the chemical liquid can be supplied to the wafer W while rotating the wafer W as shown in FIGS. 13B and 13C. Further, by configuring the nozzle and the operating mechanism, it becomes possible to apply the untreated alcohol to the entire substrate at all times, so that the uniformity of the alcohol treatment can be improved.

  Further, each nozzle 81 in which the discharge port is formed as described above moves the chemical liquid nozzle 81 in a horizontal direction perpendicular to the length direction of the nozzle from one end of the wafer W to the other end while discharging the chemical liquid, for example. A scan operation may be performed to form a paddle (puddle) on the wafer W. By forming the paddle in this way, the uniformity of the alcohol treatment can be improved.

  By the way, when a chemical solution is discharged by a straight nozzle having a fine pore opening opening downward, the impact of the chemical solution is directly transmitted to the resist film, and mist scattering occurs, resulting in a decrease in processing uniformity. In order to suppress this, it is effective to use an arm and a chemical nozzle that can adjust the nozzle angle as shown in FIGS. 14 (a) to 14 (c). As described above, the angle θ formed by the discharge direction of the chemical liquid and the wafer W is preferably 15 °. By making θ = 15 ° as compared with the case of discharging the chemical solution vertically downward, the impact of the vertical component becomes about ¼, the occurrence of mist is suppressed, and the uniformity of the alcohol treatment can be improved. Also in this case, the uniformity of processing from the center portion to the peripheral portion of the wafer W can be improved by discharging the chemical liquid onto the wafer W while the nozzle 87 performs the scanning operation via the arm.

As Example 1, the wafer was coated and developed according to the above-described steps S1 to S7. However, as the chemical solution used for rinsing in the acidic alcohol rinse module 3, 4-methyl 2-pentanol which is alcohol was used, and no acid was added to the chemical solution. In Example 2, the wafer was coated and developed according to the above-described steps S1 to S7. In Example 2, 4-methyl 2-pentanol to which an acid was added was used as the chemical solution used for rinsing in the acidic alcohol rinsing module 3 in the same manner as in the above embodiment. As a comparative example, the wafer was coated and developed according to steps S1 to S6 described above, and step S7 was not performed.

  FIGS. 14A, 14B, and 14C show, in Example 1, Example 2 and Comparative Example, black portions where residual defects are generated in the wafer surface. In the wafer of the example, the occurrence of residual defects was reduced as compared with the wafer of the comparative example, and the effect of the present invention was shown. Further, in Example 2, the generation of residue defects was further reduced as compared with Example 1, and it was shown from this result that the residue defects can be more reliably reduced by adding an acid to the alcohol.

  Subsequently, the contact angle of the resist film on the surface of each wafer of Example 1, Example 2, and Comparative Example was measured. As shown in FIG. 15, in Example 1, Example 2, and Comparative Example, the contact angles are 74.8 °, 61.5 °, and 91.4 °, respectively, in the order of Comparative Example> Example 1> Example 2. Large contact angle. That is, the hydrophilicity increases in the order of Example 2> Example 1> Comparative Example. Therefore, it was shown that residual defects can be removed by increasing the hydrophilicity of the resist surface.

1 is a plan view of a coating and developing apparatus according to an embodiment of the present invention. It is a perspective view of the coating and developing apparatus. It is a side view of the said coating and developing apparatus. It is a vertical side view of the chemical | medical solution rinse module contained in the said application | coating and image development apparatus. It is a cross-sectional top view of the said chemical | medical solution rinse module. It is a block diagram of the acidic alcohol supply part connected to the said chemical | medical solution rinse module. It is a flowchart of the process performed by the said application | coating and developing apparatus. It is process drawing which showed the process in the said chemical | medical solution rinse module. It is explanatory drawing which showed the mode of the resist surface processed with the said chemical | medical solution rinse module. It is the flowchart which showed the other process performed by the said application | coating and image development apparatus. It is explanatory drawing which showed the surface of the wafer in the said other process. It is the vertical side view which showed the structure of the image development module in the said application | coating and image development apparatus. It is explanatory drawing which showed the other structure of the nozzle of the said chemical | medical solution rinse module. It is explanatory drawing which showed other structure of the nozzle of the said chemical | medical solution rinse module. It is explanatory drawing which shows the generation | occurrence | production situation of the residue defect of the wafer measured by the Example and the comparative example. It is a graph which shows the contact angle of the wafer measured by the Example and the comparative example. It is explanatory drawing of immersion exposure.

Explanation of symbols

B2 Processing block D Residual DEV Development module L Acidic alcohol 100 Control unit 3 Chemical solution rinsing module 4 Alcohol regeneration unit 41 Chemical solution nozzle 42 Discharge port 5 Acidic alcohol supply unit 51 Acidic alcohol storage tank 64 Acidity monitor 71 Acidic solution storage tank

Claims (23)

An application module for applying a resist to the surface of the substrate;
After the resist coating, the developer is supplied to form a pattern in the resist by developing the pre Symbol resist exposure surface of the substrate, then the cleaning liquid supply to remove the developer from the substrate A developing module for performing a drying process on the substrate to remove the cleaning liquid from the substrate ;
A chemical nozzle that increases the hydrophilicity of the resist surface without altering the resist, and supplies a chemical to the substrate to remove residues attached to the resist after the drying treatment;
A coating and developing apparatus characterized by comprising:   2. The chemical liquid nozzle is provided in a chemical liquid rinsing module separate from the developing module, and the chemical liquid rinsing module includes a substrate holding unit that holds a substrate when supplying the chemical liquid. The coating and developing apparatus described.   The coating and developing apparatus according to claim 1, wherein the chemical nozzle is provided in the developing module.   The coating and developing apparatus according to claim 1, further comprising a chemical solution removing unit that removes the chemical solution from the substrate.   5. The coating and developing apparatus according to claim 4, wherein the chemical solution removing unit includes a drying unit for drying the chemical solution supplied to the substrate.   6. The coating and developing apparatus according to claim 5, wherein the drying unit is a unit that rotates a substrate holding unit that holds the substrate in order to spin dry the substrate.   7. The coating and developing apparatus according to claim 1, wherein the chemical solution is alcohol.   8. The coating and developing apparatus according to claim 7, wherein the chemical solution is an alcohol containing an acid. A chemical solution storage unit for storing the chemical solution, an acidity detection unit for detecting the acidity in the chemical solution stored in the chemical solution storage unit,
Means for controlling the supply of the acidic solution to the chemical solution reservoir so that the detected value of the acidity of the acidity detector exceeds the preset acidity;
The coating and developing apparatus according to claim 1, further comprising:   The coating and developing according to any one of claims 1 to 9, further comprising a chemical solution regeneration unit that collects the chemical solution supplied to the substrate, removes particles in the chemical solution, and supplies the chemical solution to the chemical nozzle. apparatus.   2. The exposure process according to claim 1, wherein the exposure process is an immersion exposure process in which a liquid layer that transmits light is formed on the surface of the resist, and the resist is a resist used for the immersion exposure process. The coating and developing apparatus according to any one of 10.   12. A coating and developing apparatus according to claim 1, further comprising a heating module for heating the substrate supplied with the chemical solution and drying the resist swollen by the chemical solution. .   The coating / developing apparatus according to claim 1, wherein the chemical nozzle includes a discharge port opened in a slit shape, and discharges the chemical liquid in a radial direction of the substrate.   The coating / developing apparatus according to claim 1, wherein the chemical nozzle includes a plurality of discharge ports arranged in a lateral direction and discharges the chemical liquid in a radial direction of the substrate.   15. The coating / developing apparatus according to claim 1, wherein the chemical nozzle discharges the chemical liquid onto the substrate while moving from one end side to the other end side of the substrate.   16. The coating / developing apparatus according to claim 1, wherein an angle formed between a discharge direction of the chemical liquid discharged from the chemical liquid nozzle onto the substrate and the substrate is 15 degrees. Applying a resist to the surface of the substrate;
An exposure step of exposing the resist;
Supplying a developer to the surface of the exposed substrate to form a pattern on the resist;
Supplying a cleaning solution to the substrate supplied with the developing solution to remove the developing solution;
Drying the substrate to remove the cleaning liquid;
Improving the hydrophilicity of the surface of the resist without altering the resist, and supplying the chemical liquid to the chemical liquid nozzle from the chemical liquid storage section in which the chemical liquid for removing the residue attached to the resist after the drying treatment is stored;
Discharging the chemical liquid from the chemical liquid nozzle to the substrate held by the substrate holding portion;
A coating and developing method characterized by comprising:   18. The coating and developing method according to claim 17, wherein the chemical solution is alcohol.   19. The coating and developing method according to claim 18, wherein the chemical solution is an alcohol containing an acid. Detecting the acidity in the chemical stored in the chemical storage; and
Controlling the supply of the acidic solution to the drug solution reservoir so that the detected value of the acidity exceeds a preset acidity;
The coating and developing method according to claim 17, wherein the coating and developing method is provided. 21. The coating and developing method according to claim 17, further comprising a step of collecting the chemical solution supplied to the substrate, removing particles in the chemical solution, and supplying the chemical solution to the chemical nozzle.   The coating and developing method according to claim 17, further comprising a step of heating the substrate supplied with the chemical solution and drying the resist swollen by the chemical solution. A computer program used for a coating and developing apparatus, comprising: a coating module for coating a resist on a substrate; and a developing module for developing the resist by supplying a developing solution to the surface of the substrate that has been exposed after the resist coating. Is a storage medium storing
23. A storage medium for performing the surface exposure method according to any one of claims 17 to 22.

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