JP2011210889A - Resist coating method and resist coating device, and photomask blank and method of manufacturing photomask using the resist coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist coating method and a resist coating device that speedily and uniform dry a resist coating surface by a nozzle having capillary clearance, and a photomask blank and a method of manufacturing a photomask using the resist coating method.SOLUTION: The present invention relates to: the resist coating method and the resist coating device; and the photomask blank and the method of manufacturing the photomask using the resist coating method, wherein the resist coating method in which a substrate 10 disposed with a surface 10a to be coated down is coated with a resist liquid includes guiding a resist liquid held in a liquid tank to the surface 10a to be coated by capillarity of the nozzle 24 to bring the surface 10a to be coated into contact with the liquid, relatively moving the nozzle 24 and substrate 10 in a horizontal direction to coat the surface 10a to be coated with the resist liquid 110, supplying an air current parallel with the coated surface 10a in a fixed direction at a substantially constant relative flow velocity to bring the air current into contact with the coated surface 10, and thereby drying the resist liquid 110.

Description

  The present invention relates to a resist coating method and a resist coating apparatus, and a photomask blank and a photomask manufacturing method using the resist coating method, and in particular, a resist coating method and a resist coating apparatus applicable to a relatively large substrate, The present invention also relates to a photomask blank and a photomask manufacturing method using the resist coating method.

  Conventionally, as a coating device (coater) for applying a coating solution such as a photoresist to a substrate such as a photomask blank substrate or a silicon wafer, the coating solution is dropped on the center of the substrate, and then the substrate is rotated at a high speed to perform centrifugation. A spin coater has been used in which a coating solution is extended by the action of a force to form a coating film on a substrate surface.

  However, the above-described spin coater has a problem in that a rise called resist fringe occurs at the peripheral edge of the substrate. In particular, in a liquid crystal display device or a photomask for manufacturing a liquid crystal display device, it is necessary to apply a resist to a large substrate (for example, at least a rectangular substrate having a side of 300 mm or more). It has been difficult to apply a resist to such a large substrate. Therefore, development of a technique for applying a uniform resist film to a large substrate has been desired along with the recent increase in pattern accuracy and the increase in substrate size.

  In order to solve such a problem, a coating apparatus called a CAP coater (capillary coater) is provided as an apparatus using a technique for coating a uniform resist film on a large substrate. In this CAP coater, a nozzle having a capillary gap is submerged in a liquid tank in which a coating liquid is stored, and the nozzle is raised to the vicinity of the surface to be coated of the substrate held in a downward direction so that the capillary gap Then, the coating liquid is contacted, and then the nozzle is relatively scanned over the surface to be coated to form a coating film.

In order to obtain a uniform resist film using such a CAP coater, it is important to uniformly dry the applied resist film together with uniform application using a nozzle having a capillary gap.
In order to realize this, for example, in a clean room where a downflow is configured, a coating film drying method for drying a coating film while suppressing the downflow from wrapping around the coating surface has been proposed (references). 1).
Also, in the CAP coater, after the resist is applied to the surface to be coated while moving the substrate, a drying method is proposed in which the resist film is moved back in the direction opposite to the direction moved during coating, and the resist film is dried during this movement. (See cited document 2).

JP 2003-112099 JP 2004-311884 A

In the drying method described in Patent Document 1, it is possible to suppress the influence of downflow as clean room equipment on the resist coating apparatus installed in a clean room, but to dry the coated surface quickly and uniformly. Insufficient and further improvements were desired.
The drying method described in Patent Document 2 contributes to uniform drying of the resist film applied to the surface to be coated, but the contact direction with the atmospheric gas on the surface to be coated is reversed by moving the substrate back. For this reason, and the movement distance of the substrate is limited, it is insufficient to quickly and uniformly dry the surface to be coated, and further improvement has been desired.

  Accordingly, an object of the present invention is to solve the above-described problems, and to provide a resist coating method and a resist coating that can more quickly and uniformly dry a coated surface on which a resist solution is coated with a nozzle having a capillary gap. The present invention provides an apparatus, and a photomask blank and a photomask manufacturing method using the resist coating method.

  In order to solve the above problems, one embodiment of a resist coating method according to the present invention is a method of coating a resist solution on a substrate with a surface to be coated facing downward, which is stored in a liquid tank. A resist solution is guided to the surface to be coated by capillary action of a nozzle to be in contact with the surface to be coated, and the nozzle and the substrate are moved relative to each other in the horizontal direction to apply the resist solution to the surface to be coated. The coating was performed by supplying an air flow parallel to the coated surface at a substantially constant relative flow velocity in a certain direction with respect to the coated surface, and bringing the air flow into contact with the coated resist solution. The resist solution is dried.

As the resist used in this embodiment, a known negative or positive resist can be used. The viscosity of the resist to be used is preferably in the range of 3 to 20 cps (centipoise), and more preferably in the range of 5 to 15 cps.
Although this embodiment can be applied to any substrate, it can be applied to a substrate having a side of 300 mm or more, including a photomask for manufacturing a liquid crystal display device, and particularly to a substrate having a side exceeding 1000 mm. Applicable.

  “Relatively moving the nozzle and the substrate in the horizontal direction” includes moving the nozzle, moving the substrate, and moving both. The case where the direction in which the application progresses and the direction in which the airflow advances are the same direction are also included.

  The “substantially constant relative flow velocity” means an air flow velocity that does not cause fluctuations in the relative flow velocity that affects the progress of drying of the coated surface. As the “almost constant relative flow rate”, the change in the relative flow rate is preferably within 10%, more preferably within 5%.

When coating is performed while moving the substrate, if the airflow has already been supplied and the movement of the substrate is completed at the end of coating, then at that point, with respect to any position within the coated surface of the substrate The relative flow velocity of the supplied air flow with respect to the application surface changes.
However, if the change in the relative flow rate is sufficiently small, for example, if the fluctuation is within 10% of the relative flow rate during the coating process, the relative flow rate is almost constant and the coated surface can be dried uniformly. Is possible. In addition, as the air flow, clean dry air or inert gas that has passed through a filter can be used.

  In this embodiment, as long as the traveling direction of the airflow is parallel to the surface to be coated, the relationship between the direction in which the coating proceeds and the traveling direction of the airflow can be arbitrarily set, and includes the case where they are in the same direction. Also included are cases of different directions.

  According to the present embodiment, the applied resist solution is dried by bringing an air flow parallel to the application surface with a substantially constant relative flow velocity in a fixed direction into contact with the applied resist solution, so that the applied resist solution is dried quickly and uniformly. Dry. As a result, unevenness appearing on the surface to be coated (spots with different hues visible to the naked eye) can be substantially eliminated, and variation in the in-plane distribution of the resist film thickness value is greatly reduced compared to the conventional case (for example, Halved).

  In another embodiment of the resist coating method according to the present invention, the airflow is further rectified by a rectifying plate disposed opposite to the coated surface, and an airflow parallel to the coated surface is supplied. To do.

  According to this embodiment, by rectifying the airflow with the current plate, the airflow parallel to the coated surface can be reliably supplied, and rapid and uniform drying of the coated surface can be promoted.

  Another embodiment of the resist coating method according to the present invention is further characterized in that, in the surface to be coated, the direction in which the coating proceeds and the direction in which the airflow travels are the same direction.

In this specification, “direction” and “direction” are distinguished from each other by the following definitions. Taking a vector as an example, `` direction '' means the traffic on the line connecting the starting point and the ending point without considering the vector arrow, and `` direction '' means the progress from the starting point to the ending point considering the vector arrow. Means. In other words, “the direction in which the application proceeds and the direction in which the air flow advances are the same” includes both the direction in which the application advances and the direction of the air flow in the same direction as well as in opposite directions.
In this embodiment, since the direction of application and the direction of airflow are the same, uniform drying can be achieved in the width direction of the substrate. Therefore, uniform drying of the coated surface can be realized efficiently.

  In another embodiment of the resist coating method according to the present invention, the substrate is further moved in a horizontal direction so that a resist solution is applied to the coated surface and the substrate is opposed to the moving direction. The air flow is brought into contact with the applied resist solution.

  According to this embodiment, the application can be performed by moving the substrate side without moving the liquid tank or nozzle in which the resist solution is stored. Therefore, there is no possibility that the liquid level of the resist solution in the liquid tank is disturbed and the coating behavior is disturbed by the capillary phenomenon. Furthermore, since the airflow is brought into contact with the resist solution applied in the direction opposite to the direction in which the substrate moves, the coated surface can be dried more effectively. In this case, the direction in which the application proceeds and the direction in which the air flow proceeds are the same. That is, the portion where the coating has been performed first comes into contact with the airflow first.

  Another embodiment of the resist coating method according to the present invention is further characterized in that the supply of the airflow is started before the application to the coated surface is completed.

  Since the drying starts substantially from the time when the resist solution is applied to the surface to be coated, as in this embodiment, by supplying the airflow before the coating on the surface to be coated is completed, it is possible to quickly and uniformly Can dry the coated surface.

  Another embodiment of the resist coating method according to the present invention is further characterized in that the supply of the airflow is started before the coating on the coated surface is started.

  According to this embodiment, since the supply of the airflow is started before the application to the surface to be applied is started, the resist solution is contacted with the airflow immediately after being applied to the surface to be applied, and the drying is performed quickly. Thus, uniform drying of the coated surface can be realized more reliably.

  Another embodiment of the resist coating method according to the present invention is further characterized in that a flow velocity of the airflow is 10 times or more with respect to a speed of the relative movement of the nozzle and the substrate.

  According to this embodiment, since the flow velocity of the airflow is 10 times or more than the relative movement speed of the nozzle and the substrate, it corresponds to the airflow having the “substantially constant relative flow velocity” and is always applied. The inside can be dried uniformly.

  Another embodiment of the resist coating method according to the present invention is further characterized in that the flow velocity of the air flow is 0.05 to 1.5 m / sec.

  By setting the flow velocity of the air flow within the range of this embodiment, the inside of the coated surface can be quickly and uniformly dried.

  One embodiment of a photomask blank manufacturing method according to the present invention is a photomask blank manufacturing method including a step of applying a resist to a photomask blank substrate having an optical film formed on a transparent substrate, A resist is applied by any of the above resist application methods.

  Here, a transparent substrate made of quartz glass or the like can be used, and the optical film includes a light shielding film, a semi-transparent film, a phase shift film, an antireflection film laminated thereon, and the like. In this embodiment, a photomask blank that exhibits the same effects as described above and is optically excellent can be obtained.

  Another embodiment of the method for producing a photomask blank according to the present invention is a method for producing a photomask by patterning a transfer pattern according to an electronic device to be obtained on an optical film on a transparent substrate. The photomask blank described above is used.

  According to this embodiment, an optically excellent photomask blank on which a desired transfer pattern is formed can be obtained.

  Another embodiment of the method for manufacturing a photomask blank according to the present invention is a method for manufacturing a photomask in which a plurality of optical films formed on a transparent substrate are patterned, and a resist is applied. Performing a drawing and development process on the resist to pattern the first optical film to form a photomask intermediate having a first transfer pattern; and applying a resist to the photomask intermediate Applying, patterning and developing on the resist, and patterning the second optical film to form a photomask having a second transfer pattern or a photomask intermediate. Any of the above resist coating methods is used for coating the resist.

  In the photomask manufacturing process, discharge may occur due to a potential difference caused by static electricity, and electrostatic damage may occur in which the optical film melts due to energy at that time. For example, when patterning a plurality of optical films, at the time of the second patterning, discharge may occur between the patterns of the already patterned optical films, and the pattern shape may be broken. In particular, when a pattern with a sharp tip is approaching, electrostatic breakdown is likely to occur. However, in the present embodiment, electrostatic breakdown can be prevented in advance by supplying an air flow having an appropriate humidity (for example, humidity 40 to 70%).

  One embodiment of a resist solution coating apparatus according to the present invention is a resist coating device for applying a resist solution to a substrate with a surface to be coated facing downward, a liquid tank for storing the resist solution, and the liquid A coating means having a nozzle that guides the resist solution stored in the tank to the coated surface of the substrate by capillary action, and moving at least one of the nozzle and the substrate to make the two relative to each other in the horizontal direction. A moving means for moving, an air flow generating source for generating an air flow, and a guide surface arranged to face the coated surface at a predetermined separation distance, and rectifies the air flow into a flow parallel to the coated surface. A drying mechanism provided with a current plate, and in a state where the resist solution is in contact with the surface to be coated by capillary action by the coating means, the nozzle and the substrate are horizontally moved by the moving means. The resist solution is applied to the surface to be coated by moving the surface, and an air flow parallel to the surface to be coated is supplied to the surface to be coated at a substantially constant relative flow velocity in a certain direction by the drying means. The applied resist solution is dried by bringing the airflow into contact with the applied resist solution.

  Here, “moving at least one of the nozzle and the substrate to relatively move both in the horizontal direction” includes moving the nozzle, moving the substrate, and moving both. It is. Moreover, if the traveling direction of the airflow is parallel to the surface to be coated, the relationship between the direction in which the coating proceeds and the traveling direction of the airflow can be arbitrarily set. That is, the direction in which the application proceeds and the direction in which the air flow proceeds are included in the same direction or in different directions.

  In the manufacture of a photomask for manufacturing a liquid crystal display device and the like, frequent size changes often occur depending on the final product, but in this embodiment, even if the size of the photomask to be manufactured is changed, It has the advantage of not requiring major changes. In other words, in the application to the substrate whose size is within the nozzle width, even if the size of the substrate is changed, it is not necessary to replace the nozzle itself, and it is not necessary to replace the air flow source or the current plate for the drying means.

  If the coating apparatus of this embodiment is used, the applied resist solution is dried by bringing an air flow parallel to the coated surface with a substantially constant relative flow velocity in a fixed direction into contact with the applied resist solution. Quick and uniform drying can be achieved. As a result, unevenness appearing on the surface to be coated (spots with different hues visible to the naked eye) can be substantially eliminated, and variation in the in-plane distribution of the resist film thickness value is greatly reduced compared to the conventional case (for example, Halved).

  Another embodiment of the resist solution coating apparatus according to the present invention is further characterized in that the separation distance is adjustable, and the separation distance is adjusted according to a flow velocity of the airflow.

If the distance between the coated surface and the guide surface of the rectifying plate is too large, the air flow rectifying effect will be diminished, while if it is too close, the unevenness of the guide surface of the rectifying plate (surface smoothness due to scratches, resist adhesion, etc.) Inconveniences such as non-uniformity). In particular, when the flow velocity of the airflow is high, the risk of picking up the non-uniformity factor of the guide surface sensitively increases.
Therefore, as in this embodiment, by adjusting the separation distance according to the flow rate of the airflow, even if the resist coating process is continued for a long time, the rapid and uniform drying of the coated surface can be stably maintained. Can do.

  In another embodiment of the resist solution coating apparatus according to the present invention, the nozzle and the substrate are relatively moved in the horizontal direction by moving the substrate in the horizontal direction by the moving means, and the air flow is generated. The source moves together with the substrate.

  According to this embodiment, according to this embodiment, the application can be performed by moving the substrate side without moving the liquid tank or nozzle in which the resist solution is stored. Therefore, there is no possibility that the liquid level of the resist solution in the liquid tank is disturbed and the coating behavior is disturbed by the capillary phenomenon. Furthermore, since application and drying can be performed without changing the relative position between the coated surface of the substrate and the air flow generation source, a constant air flow can always be brought into contact with the resist solution coated on the coated surface. .

  As described above, in the present invention, the applied resist solution is dried by contacting the applied resist solution with an air flow parallel to the application surface having a substantially constant relative flow velocity in a fixed direction. Rapid and uniform drying can be realized, whereby unevenness appearing on the surface to be coated can be substantially eliminated, and variation in the in-plane distribution of the resist film thickness value can be greatly reduced.

1 is a schematic side view showing an embodiment of a resist coating apparatus according to the present invention. It is a schematic front view which shows one Embodiment of the coating device of the resist which concerns on this invention. It is a schematic side view which shows one Embodiment of the application | coating means of the resist which concerns on this invention. It is a schematic diagram which shows one Embodiment of the drying means which concerns on this invention. It is a schematic diagram which shows other embodiment of the baffle plate which concerns on this invention. It is a schematic diagram which shows other embodiment of the drying means which concerns on this invention. It is a schematic diagram which shows other embodiment of the drying means which concerns on this invention. It is a schematic diagram showing an embodiment of a manufacturing method of a photomask (a photomask having a film configuration in which a semi-transparent film is an upper layer) in which a plurality of optical films are formed on a transparent substrate. It is a schematic diagram which shows embodiment of the manufacturing method of the photomask (The photomask of the film | membrane structure which has a semi-transparent film in the lower layer) in which the some optical film was formed on the transparent substrate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, an embodiment of a resist coating method and a resist coating apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic side view of a coating apparatus 1 according to this embodiment, and FIG. 2 is a schematic front view as viewed from the left side of FIG. FIG. 3 is a schematic cross-sectional view showing the coating means 2 which is a main component device of the coating apparatus 1.

  As shown in FIG. 1, a coating apparatus 1 includes a coating unit 2 provided on a base frame 11, a suction unit 3 provided on a moving frame 12, and a moving unit 4 that moves the moving frame 12 in a horizontal plane. A holding means 5 that detachably holds the substrate 10 and is attached to the suction means 3, a drying means 100 that supplies an air flow to dry the coated surface of the substrate 10 coated with the resist solution, and a control (not shown) Department.

The coating means 2 is for applying a resist solution to the substrate 10 with the surface to be coated facing downward. The coating means 2 is provided at substantially the center of a rectangular box-shaped base frame 11. is there.
Specifically, as shown in FIG. 3, a motor-driven lift unit 22 that lifts and lowers the support plate 21, a nozzle 24 having a capillary gap 23, and an upper end portion of the support plate 21 are fixed. A liquid tank 25 that is stored in a state where it is immersed in the coating liquid 20, and an air cylinder drive type nozzle lifting / lowering unit 26 that projects the nozzle 24 to a predetermined height from the liquid tank 25, and further measures the thickness of the substrate 10. As a measuring means, a linear gauge 9 is provided on the side of the liquid tank 25. A more detailed description will be given later with reference to FIG.

  A known negative or positive resist can be used as the resist applied in this embodiment, and the viscosity of the resist used is preferably 3 to 20 cps (centipoise), and more preferably 5 to 15 cps. In the present embodiment, the coating apparatus 1 is used for applying the dyst liquid. However, the present invention is not limited to this, and the coating hand apparatus 1 can be applied to application of any other coating liquid.

The moving frame 12 is formed integrally with a pair of opposing side plates and a top plate that connects the side plates, so that the positional accuracy between the substrate 10 and the coating means 2 is not distorted due to insufficient rigidity. It has sufficient mechanical strength.
The moving frame 12 is connected to the base frame 11 via the linear way 41 so as to be movable in the horizontal direction.
Further, the moving frame 12 is provided with an adsorbing means 3 comprising an adsorbing plate having a plurality of adsorbing holes (not shown) formed at substantially the center of the top plate. Further, one side plate of the moving frame 12 is provided with a projecting portion 13 formed with a nut into which a ball screw 42 described later is screwed.

The moving means 4 includes a linear way 41 that moves while guiding the side plate of the moving frame 12, a ball screw 42 that is screwed into a nut of the moving unit 13, and a motor 43 that rotates the ball screw 42.
When the motor 43 is rotated by an instruction from the control unit, the ball screw 42 rotates, and the moving unit 13 can be horizontally moved by a predetermined distance in a direction corresponding to the rotation direction of the ball screw 42.

The holding means 5 includes four holding members 55 that hold the peripheral portions of the four corners of the substrate 10. These holding members 55 are fixed to the holding plate 61 for each holding member 55.
Here, it is preferable to provide a pressing means (not shown) so that the substrate 10 set on the holding member 55 is not detached from the holding member 55. For example, the presser means is configured such that the presser plate moves up and down and swings in the horizontal direction. As a result, the substrate 10 set on the holding member 55 is inclined and pressed in the direction of the holding member 55.

Two holding plates 61 are arranged on the rails 63 arranged in parallel with each other in the Y direction (see FIG. 1) via the linear way 62, and the two holding plates 61 on the back side are arranged. Can be moved in the Y direction by a driving means (not shown) using a ball screw and a motor. Thereby, when the vertical dimension of the board | substrate 10 differs, the holding plate 61 can be moved to a Y direction by the said drive means, and it can oppose easily to the board | substrate 10 from which a vertical dimension differs.
Moreover, the rail 63 is attached to the rotating plate 65 at both ends via a linear way 64 arranged in parallel and facing in the X direction (see FIG. 2), and uses a ball screw and a motor. It can be moved in the X direction by a driving means (not shown). Thereby, when the horizontal dimension of the board | substrate 10 differs, the holding plate 61 can be moved to the X direction by the said drive means, and it can face easily the board | substrate 10 from which a horizontal dimension differs.

  The rotating plate 65 has a front end rotatably connected to a base plate 69 via a rotating shaft 66, and a rear end positioned horizontally by a stopper 68 protruding from the base plate 69. It is supported by. The rotation plate 65 is rotated by a predetermined angle by a rotation cylinder 67. The rotating cylinder 67 has a rod end rotatably connected to the rotating plate 65, and an end of the cylinder body is rotatably connected to the base plate 69.

  The base plate 69 has guide bars 71 projecting from the holding means frame 70 at the four corners of the lower surface, and can be moved in the vertical direction by lifting means 73 such as an air cylinder provided on the bottom frame 72. it can.

  The drying means 100 includes a blower unit 102 and a current plate 104 installed on the base frame 11 via a base member 106. The airflow discharged from the blower unit 102 and guided by the rectifying plate 104 flows from the right to the left in FIG. 1 substantially parallel to the Y direction. By this air flow, the coated surface of the substrate 10 coated with the resist solution by the coating means 2 can be quickly and uniformly dried. A more detailed description will be given later with reference to FIG.

<Description of outline of operation of coating apparatus 1>
Next, an outline of the operation of the coating apparatus 1 having the above configuration will be described with reference to FIG.
First, in the coating apparatus 1, the base plate 69 is not lifted by the lifting / lowering means 73, the rotating plate 65 is supported horizontally, the moving frame 12 is at the processing end position, and the coating means 2 is not lifted. The state is the initial state.
The holding member 55 is adjusted in advance according to the vertical dimension and the horizontal dimension of the substrate 10. In this adjustment, the holding member 55 can be easily positioned according to the lateral dimension of the substrate 10 by moving the rail 63 in the X direction. Further, by moving the two holding plates 61 on the back side in the Y direction, the holding member 55 can be easily positioned according to the vertical dimension of the substrate 10.

  Next, the rotating plate 65 is moved to the set position while being rotated by the rotating cylinder 67 so as to get up to the near side (counterclockwise in FIG. 1). Then, when an operator working on the front side of the coating apparatus 1 sets the substrate 10 on the holding member 55 with the surface to be coated facing the coating apparatus 1, the pressing means presses the substrate 10 against the holding member 55. . Thereby, the coating apparatus 1 can prevent the malfunction that the board | substrate 10 set to the holding member 55 of the state inclined diagonally remove | deviates from the holding member 55, and falls.

Next, the rotation plate 65 is rotated by the rotation cylinder 67 so as to fall to the back side (clockwise in FIG. 1), and the back end of the rotation plate 65 abuts against the stopper 68 and becomes horizontal. Supported. And if the board | substrate 10 is supported horizontally, the holding means will release the holding of the board | substrate 10. FIG.
Thereby, the board | substrate 10 will be in the state placed horizontally at the mounting position. Note that the presser unit in the state where the presser is released is lower than the upper surface of the substrate 10, and therefore does not come into contact with the suction unit 3 even if the substrate 10 is raised.

Next, the moving frame 12 is moved from the processing end position to the mounting position by the moving means 4 so that the suction position of the suction means 3 is positioned on the substrate 10. At this time, the coating means 2 is in a lowered state.
Subsequently, the lifting / lowering means 73 raises the base plate 69 until the upper surface of the substrate 10 contacts the suction means 3.

Next, when the suction means 3 is sucked from the suction holes (not shown), the substrate 10 is sucked by the suction means 3, and then the elevating means 73 is lowered.
Next, as the moving frame 12 moves to the processing position side, the coating unit 2 rises to a predetermined position and coats the coating liquid on the surface to be coated of the substrate 10. At this time, the coating means 2 brings the coating liquid raised to the tip of the nozzle by capillary action into contact with the surface to be coated, and then adjusts the nozzle position so that the desired coating thickness is obtained, and this vertical clearance is set. When the moving frame 12 passes through the processing position in the maintained state, a coating film having a uniform film thickness can be formed on the substrate 10.

At this time, an air flow is supplied by the drying means 100, and the coated surface of the substrate 10 coated with the resist solution by the coating means 2 is quickly and uniformly dried. In addition, about the supply start time of airflow, it is preferable to start before ending application | coating, and it is still more preferable to start before starting application | coating.
In addition, when the supply of airflow is started before the start of coating, it is also possible to supply the airflow before the liquid contact, or after the liquid contact (for example, the nozzle is lowered after the liquid contact to apply the liquid It is also possible to start the air flow when a suitable application gap is created.

  When the moving frame 12 moves to the processing end position, the coating unit 2 descends, reverses the moving direction of the moving frame 12, and moves from the processing end position to the mounting position in the Y direction. It should be noted that the supply of airflow can be stopped once the drying has progressed to a point where the in-plane distribution of the resist applied by the surrounding environment is not affected. Specifically, the supply of airflow can be stopped about 5 to 15 minutes after the start of application.

Then, the lifting and lowering means 73 raises the base plate 69 until the holding member 55 comes into contact with the substrate 10. When the holding member 55 comes into contact with the substrate 10, the suction means 3 stops the suction, and the substrate is detached by air blow. The substrate 10 is placed on the holding member 55.
In addition, in the case where charges are accumulated in the substrate 10, if the holding member 55 is made of an insulating material, when the substrate 10 is placed on the holding member 55, at the contact portion between the substrate 10 and the holding member 55. There is a possibility of causing electrostatic breakdown. In order to prevent such electrostatic breakdown, it is preferable to use a conductive material such as metal as the holding member 55.

Subsequently, after the lifting / lowering means 73 lowers and stops the base plate 69, the pressing means presses the substrate 10 against the holding member 55, and then rotates the rotating plate 65 to the front side.
Next, when the rotation of the rotation plate 65 is stopped, the pressing means is released, and the operator can easily remove the substrate 10 on which the coating film is formed from the holding member 55.

  As described above, according to the coating apparatus 1 of the present embodiment, even when the coating liquid is applied from below with the surface to be coated of the substrate 10 facing downward, an error in the vertical direction is caused on the moving means 4 side. Since no reversing means is provided and the positional accuracy in the vertical direction between the substrate 10 and the nozzles of the coating means 2 can be increased, a coating film having a uniform thickness can be formed on the substrate 10. Furthermore, the surface to be coated of the substrate 10 is quickly and uniformly dried by supplying the airflow by the drying means 100, so that the quality is greatly improved compared to the conventional one in terms of unevenness in appearance performance and variations in resist film thickness. .

As can be seen from FIG. 1, when the substrate 10 is set, the holding means 5 is rotated and inclined, so that the operator does not have to invert the substrate 10 by 180 degrees, and the inclined angle. The substrate 10 can be easily set or removed from the holding member 55 by the amount.
Further, the holding means 5 includes a rail 63 movably attached to the rotating plate 65 via a linear way 64, a holding plate 61 movably attached to the rail via a linear way 62, and the holding Since the holding member 55 attached to the plate 61 is provided, the position of the holding member 55 can be quickly and easily changed with respect to the substrates 10 of different sizes, and the productivity in switching the models is improved. be able to.

Although this embodiment can be applied to a substrate having an arbitrary size, it is preferably applied to a photomask for manufacturing a liquid crystal display device using a positive resist, particularly a substrate having a size of 300 mm or more on a side and having a width of 1000 mm. It can be applied to a substrate exceeding this.
In manufacturing a photomask for manufacturing such a liquid crystal display device, frequent size changes often occur depending on the final product, but in this embodiment, even if the size of the photomask to be manufactured is changed, the device It has the advantage of not requiring the major changes above. That is, in the application to the substrate 10 whose size is within the width of the nozzle 24, even if the size of the substrate 10 is changed, it is not necessary to replace the nozzle 24 itself. There is no need to replace any.

<Description of Embodiment of Application Unit 2>
Next, an embodiment of the application unit 2 will be described in more detail with reference to FIG. As described above, the coating means 2 is fixed to the motor-driven lift unit 22 that lifts and lowers the support plate 21, the nozzle 24 having the capillary gap 23, and the upper end of the support plate 21. A liquid tank 25 that is stored in a state immersed in the liquid tank 20, an air cylinder drive type nozzle elevating part 26 that causes the nozzle 24 to protrude from the liquid tank 25 to a predetermined height, and a linear gauge 9 that measures the thickness of the substrate 10. Prepare.

The elevating unit 22 includes an elevating mechanism that can finely adjust the height of the support plate 21 by a motor (not shown) controlled by the control means. That is, the elevating unit 22 serves as elevating means for elevating and lowering the nozzle 24 while controlling the gap between the nozzle 24 and the surface to be coated of the substrate 10.
Moreover, the nozzle raising / lowering part 26 raises the nozzle 24 only a fixed distance from the state accommodated in the liquid tank 25 to the state which protrudes a front-end | tip part by the air cylinder (not shown) controlled by a control means. Elevating mechanism is provided.

  Here, the liquid tank 25 is fixed to the upper part of the support plate 21, and the linear gauge 9 is fixed to the side surface of the liquid tank 25. Further, the nozzle 24 is connected to the liquid tank 25 by the nozzle elevating part 26. As a result, it rises by a certain distance. Therefore, when the elevating part 22 controls the height of the support plate 21, the heights of the linear gauge 9, the liquid tank 25, and the protruding nozzle 24 are simultaneously controlled.

  By the above control, the coating means 2 brings the coating liquid raised to the tip of the nozzle by capillary action into contact with the surface to be coated, and then adjusts the nozzle position so as to obtain a desired coating thickness. When the moving frame 12 passes through the processing position while maintaining the clearance, a coating film having a uniform film thickness can be formed on the substrate 10.

  The resist used in the present embodiment can be a known negative or positive resist, and the viscosity of the resist is preferably in the range of 3 to 20 CPS (centipoise), and in the range of 5 to 15 CPS. More preferably.

<Description of Embodiment of Drying Unit 100>
Next, one embodiment of the drying means 100 according to the present invention will be described in detail with reference to FIG. FIG. 4 is a schematic diagram showing the main components of the coating apparatus 1 related to the drying means 100. FIG. 4 (a) shows a side surface of the drying means 100, and FIG. 4 (b) shows FIG. It represents a plane viewed from above in a). However, in FIG. 4B, the description of the suction means 3 and the substrate 10 is omitted.

  FIG. 4 shows the nozzle 24 of the coating means 2 for guiding the resist solution stored in the liquid tank to the coated surface of the substrate 10 by capillary action, the suction means 3 moved in the horizontal direction by the moving means 4, and the suction means. The substrate 10 held in a state in which the surface to be coated is directed downward by the suction force 3, the air flow generation source 102 that generates an air flow, and the guide surface 104 a are arranged to face the surface to be coated 10 a at a separation distance t, A rectifying plate 104 that rectifies the flow parallel to the coated surface 10a is shown. Here, the drying mechanism 100 is mainly configured by an air flow generation source 102 and a rectifying plate 104.

In a state where the resist solution is in contact with the coated surface 10a by capillary action by the nozzle 24 of the coating means 2, the suction means 3 that has sucked the substrate 10 is moved horizontally by the moving means 4, and the nozzle 24 and the substrate 10 are moved. Is moved relative to the horizontal direction. Thereby, the resist solution 110 can be applied to the coated surface 10a. At this time, by the drying means 100, an airflow is applied to the surface 10a to be coated at an almost constant relative flow velocity in a certain direction and parallel to the surface 10a to be coated (see the arrow in FIG. 4). The applied resist solution 110 can be dried by contacting the resist solution 110.
The nozzle 24 of the coating means 2 is installed at the center of the base frame 11, and the drying mechanism 100 is connected to the end of the base frame 11 via the base member 106. Although the substrate 10 moves, the positional relationship between the coating unit 2 and the drying unit 100 does not change.

  The air flow generation source 102 mainly includes a drive unit 102a and a blower nozzle 102b. A fan with a filter (not shown) driven by an electric motor is disposed inside the driving unit 102a, and the airflow that has passed through the filter by the rotation of the fan is discharged from the air blowing opening of the air blowing nozzle 102b, and the application unit 2 To the nozzle 24 side. The clean airflow that has passed through this filter is indicated by the arrows in FIG. As a fan used for the drive unit 102a, any type of fan including a sirocco fan and a turbo fan can be used.

  In the present embodiment, the blow nozzle 102b is divided into four chambers in a direction orthogonal to the flow of the air flow, and by providing a damper or the like in each chamber, the air velocity of the air flow in each chamber can be adjusted. . Furthermore, it is also possible to provide a blower unit having an individual fan for each chamber so that the air velocity of the airflow of each blower unit can be adjusted. In addition, the number which divides the ventilation nozzle 102b is not restricted to four, It can divide into arbitrary numbers, The integral ventilation nozzle 102b can also be used without dividing.

  The airflow to be supplied can be supplied by sucking and discharging the gas filled in the clean room by the fan of the drive unit 102a, or by supplying the gas from another gas supply source to the fan of the drive unit 102a. It can also be supplied by discharging. Moreover, a heating means can be provided to keep the airflow at a predetermined temperature, and a moisturizing means can be provided to keep the airflow at a predetermined humidity. The airflow humidity will be described later.

  The guide surface 104a of the rectifying plate 104 is disposed to face the application surface 10a with a separation distance t, and the guide surface 104a has a smooth surface property. As shown in FIG. 4, the rectifying plate 104 is disposed so as to continuously guide the airflow from the lower side from the blower nozzle 102 b to the position of the nozzle 24 of the applying means 2.

  The guide surface 104a of the rectifying plate 104 and the coated surface 10a are “facing each other” when the guide surface 104a and the coated surface 10a as shown in FIG. 4 are disposed in parallel (this embodiment). 5), for example, as shown in FIG. 5, a wedge-shaped airflow in which the distance between the guide surface 104a and the coated surface 10a is wide on the airflow generation source 102 side and narrowed on the nozzle 24 side. The case where the flow path is formed is also included. Even in this case, the distance between the guide surface 104a and the coated surface 10a is the same in the direction orthogonal to the flow of the air flow, and an air flow parallel to the coated surface 10a can be supplied. .

  Although the kinetic energy of the airflow decreases as the distance from the airflow generation source 102 increases, the reduction of the airflow velocity can be compensated by the arrangement of the rectifying plate 104 as shown in FIG. As the current plate 104 and the material, any material including resin and metal can be used.

  If the separation distance t between the coated surface 10a and the guide surface 104a of the rectifying plate 104 is too large, the air flow rectifying effect is weakened. On the other hand, if the separation distance t is too close, the unevenness factor of the guide surface 104a of the rectifying plate 104 is sensitively picked up. This causes inconvenience. In particular, when the flow velocity of the airflow is high, the risk of picking up the non-uniformity factor of the guide surface sensitively increases. Therefore, it is preferable that the separation distance t can be adjusted according to the flow velocity of the airflow. By doing in this way, the optimal airflow which implement | achieves quick and uniform drying of the to-be-coated surface can be obtained. Also, for example, when the substrate is a photomask or photomask blank substrate, there are many types of plate thickness depending on the product, and in order to form optimum rectification for each substrate of different plate thickness, the height of the rectifier plate is It is preferably variable.

For example, the guide surface 104a of the rectifying plate 104 may be stained or scratched with resist during use. If the guide surface 104a is too close, the unevenness (for example, unevenness of several tens to several hundreds μm) may occur. There is a risk of reflection on the resist coating surface. Further, when the air flow generation source 102 has a plurality of fans for each room in the direction orthogonal to the air flow, the air flow near the boundary may be disturbed. Therefore, the influence can be reduced by adjusting the separation distance t according to each situation.
In addition, when the surface property of the guide surface 104a becomes non-uniform in the direction orthogonal to the air flow, the air velocity of the air flow should be adjusted for each room in the direction orthogonal to the air flow. You can also.

  The specific dimension of the separation distance t is preferably 1 to 50%, more preferably 10 to 50% with respect to the second speed value of the relative speed of the surface to be coated 10a and the airflow. For example, when the relative velocity between the surface to be coated 10a and the airflow is 0.1 to 1 m / second, the separation distance t is preferably selected within a range of 10 to 50 mm. The flow rate of the airflow will be described in detail in the description of the resist coating method below.

  In the present embodiment, as shown in FIG. 4A, eaves portions 108 are provided at both ends of the suction means 3 so that the downflow in the clean room is caught and the supplied airflow is not affected. Yes. However, the eaves portion 108 is not necessarily a member to be provided.

In the present embodiment, in the coated surface 10a, the direction in which the application proceeds and the direction in which the air flow proceeds are the same direction. In particular, in this embodiment, the substrate 10 coated with the resist by the nozzle 24 of the coating unit 2 is moved horizontally from left to right in the drawing by the moving unit 4 with the coated surface 10a facing downward. At this time, if an airflow is already supplied, the airflow flowing from the right to the left in the drawing contacts the resist solution 110 applied to the application surface 10a in parallel. Is dried quickly and evenly.
At this time, the substrate 10 is dried at a relative flow rate obtained by adding the moving speed of the substrate 10 and the flow rate of the airflow. When the airflow reaches the nozzle 24 of the coating means 2, the flow is divided into left and right and leaves the region where the substrate 10 is present.

  The coating surface 10a is dried by the airflow until the substrate 10 reaches the processing end position and stops, and further, the substrate 10 moves in the opposite direction and reaches the mounting position. When the moving means 4 (substrate 10) moves in the opposite direction, the substrate 10 is dried at a relative flow rate obtained by subtracting the moving speed of the substrate 10 from the flow rate of the airflow. When drying by such an air current causes the drying to proceed to a point where the in-plane distribution of the applied resist is not affected by the surrounding environment, the supply of the air current can be stopped. Specifically, the supply of the air current can be stopped about 5 to 15 minutes after the start of coating, and then the substrate 10 can be detached from the coating apparatus 1.

  According to this embodiment, since the width dimension of the blowing nozzle 102b and the current plate 104 of the drying means 100 is equal to or larger than the width dimension of the nozzle 24, each member of the drying means 100 is changed even if the size of the substrate to which the resist is applied is changed. There is no need to replace.

<Description of Other Embodiments of Drying Unit 100>
In the embodiment shown in FIG. 4, the resist is applied and dried by moving the substrate 10 in a state where the positional relationship between the airflow generation source 102 and the nozzle 24 does not change. However, the present invention is not limited to this. Absent. For example, the airflow generation source 102 can be installed on the substrate 10 side. In this case, by moving the substrate 10 in the horizontal direction by the moving means 4, the nozzle 24 and the substrate 10 are relatively moved in the horizontal direction, and the airflow generation source 102 moves integrally with the substrate 10. However, the current plate 104 is continuously installed from the nozzle 24.
In this case, it is possible to perform coating and drying without changing the relative position between the coated surface 10a of the substrate 10 and the air flow source 102, and a resist solution in which a stable air flow is always applied to the coated surface 10a. Can be contacted.

In the embodiment shown in FIG. 4, the direction in which the application proceeds and the direction in which the air flow proceeds are the same direction, but the present invention is not limited to this. For example, as shown in FIG. 6, it is conceivable that the flow of airflow is orthogonal to the traveling direction of the substrate 10, and as shown in FIG. An oblique case is also conceivable.
In the case shown in FIG. 6, the airflow does not collide with the nozzle 24, and in the case shown in FIG. 7, the airflow changes its direction without causing a frontal collision with the nozzle 24, so that the airflow flows more smoothly.
In any case, when an air flow is introduced from the side of the substrate 10, there is a difference in conditions in the width direction of the substrate 10, which is considered suitable for the application of a relatively narrow substrate.

<Description of Embodiment of Resist Coating Method Using Drying Means 100>
Next, an embodiment of a resist coating method using the drying means 100 will be described with reference to FIG.
In this resist coating method, the resist solution stored in the liquid tank 25 is guided to the coated surface 10a by the capillary action of the nozzle 24 by the coating means 2, and is brought into contact with the coated surface. By relatively moving the substrate 10 in the horizontal direction, the resist solution 110 is applied to the application surface 10a. At this time, the drying means 100 supplies an air flow parallel to the surface to be coated at a substantially constant relative flow velocity in a certain direction with respect to the surface to be coated 10 b, thereby bringing the air flow into contact with the coated resist solution 110. Then, the applied resist solution 110 is dried.

  When the drying proceeds to a point where the in-plane distribution of the resist applied by the surrounding environment is not affected, the supply of airflow is stopped. For example, the supply of airflow can be stopped about 5 to 15 minutes after the start of application, and then the substrate 10 can be removed from the application apparatus 1.

  In particular, by rectifying the airflow with the rectifying plate 104 having the guide surface 104a parallel to the coated surface 10a, a smooth airflow parallel to the coated surface 10a can be supplied. As a result, the surface to be coated can be quickly and uniformly dried. As a result, unevenness in appearance performance (spots with different hues that can be visually confirmed) is almost eliminated, and the in-plane distribution of the resist film thickness value is obtained. Compared with a conventional drying method (for example, the drying method shown in FIG. 6 of Patent Document 2), the amount can be reduced by almost half.

  Here, the direction in which the application progresses and the direction in which the airflow advances can take any direction, but it is preferable that the direction in which the application advances and the direction in which the airflow advances are the same. In this case, as shown in FIG. 4, when the resist solution is applied to the application surface 10a by moving the substrate 10 in the horizontal direction, the airflow is applied in the direction opposite to the direction in which the substrate 10 moves. This is brought into contact with the resist solution 110.

In this case, since the coating is performed by moving the substrate 10 side without moving the liquid tank 25 and the nozzle 24 in which the resist liquid is stored, the liquid level of the resist liquid in the liquid tank 25 is disturbed, There is no risk of the coating behavior being disturbed by capillary action. Furthermore, since the airflow is brought into contact with the resist solution 110 applied in the direction opposite to the direction in which the substrate 10 moves, the coated surface 10a can be dried more effectively.
However, the present invention is not limited to this, and an airflow can be brought into contact with the coated resist solution 110 in the same direction as the moving direction of the substrate 10.

The timing for starting the supply of airflow is preferably started before the application to the coated surface 10a is completed, and more preferably started before the application to the coated surface 10a is started.
Although the drying starts substantially from the time when the resist solution is applied to the coated surface 10a, the supply of the airflow is started before the application to the coated surface 10a is completed. Drying can be realized. Further, in the case where the supply of the airflow is started before the application to the coated surface 10a is started, the drying is performed in contact with the airflow immediately after the resist solution is applied to the coated surface 10a. And uniform drying of the coated surface can be realized more reliably.

  When the supply of the airflow is started before the application to the coated surface 10a is started, it is possible to supply the airflow before the liquid contact, or after the liquid contact (for example, the nozzle after the liquid contact) It is also possible to start the air flow at the point of lowering and creating a coating gap suitable for coating.

The flow rate of the airflow to be supplied is preferably 10 times or more, more preferably 50 times or more the relative movement speed of the nozzle and the substrate.
By taking such a flow rate, an air flow having a substantially constant relative flow rate can be supplied regardless of the relative movement between the substrate 10 and the nozzle 24, so that the coated surface 10a can be dried uniformly. Can do.
Here, the relative movement speed of the nozzle and the substrate is preferably in the range of 0.05 to 1 m / min, and more preferably in the range of 0.1 to 0.5 m / min. The flow rate of the airflow is preferably 0.05 to 1.5 m / sec, and more preferably 0.1 to 1.5 m / sec.

<Description of Embodiment for Manufacturing Photomask Blank and Photomask>
A photomask blank can also be manufactured by apply | coating a resist to the photomask blank board | substrate with which the optical film was formed on the transparent substrate with said resist application method. In the present embodiment, a transparent substrate made of quartz glass or the like can be used, and the optical film includes a light shielding film, a semi-transparent film, a phase shift film, an antireflection film laminated thereon, and the like. Further, by using this photomask blank, a photomask can be manufactured by patterning a transfer pattern corresponding to the electronic device to be obtained on the optical film on the transparent substrate.

<Description of Embodiment for Manufacturing Photomask Formed with Multiple Optical Films>
Next, with reference to FIGS. 8 and 9, a description will be given of a case where a photomask having a plurality of optical films formed on a transparent substrate is manufactured by applying the above resist coating method.
8 and 9, as an example of a photomask on which a plurality of optical films are formed, there is a manufacturing method of a photomask on which a semi-transparent film (HTL: Half Tone Layer) is formed in addition to a light shielding film. It is shown. This photomask can express a gray portion by adding a semi-transparent film to express the gray portion. For example, the number of steps can be reduced in manufacturing a liquid crystal display device.

  FIG. 8 shows a manufacturing process of a photomask having a film configuration in which a semi-transparent film (HTL) is formed later and, as a result, the semi-transparent film is an upper layer. FIG. 9 shows a semi-transparent film. (HTL) is formed first, and as a result, a manufacturing process of a photomask having a film structure in which a semi-transparent film is disposed below is shown.

In the manufacturing process of the photomask having the film configuration shown in FIG. 8, the first time is applied to the transparent substrate (see FIG. 8A) in which the Cr-based light shielding film (CR) and the antireflection film (AR) are laminated in this order from the lower layer. A resist film is formed to form a resist film, and pattern exposure and development are performed on the resist film to form a first resist pattern (see FIG. 8B). Thereafter, by etching using this resist pattern as a mask, the Cr-based light shielding film (CR) and the antireflection film (AR) are patterned, and a semi-transparent film (HTL) is laminated thereon to form a photomask intermediate. It forms (refer FIG.8 (c)).
Next, a second resist coating is performed on the photomask intermediate to form a resist film, and pattern exposure and development are performed on the resist film to form a second resist pattern (see FIG. 8D). . Then, by etching using this resist pattern as a mask, a photomask or photomask intermediate in which the semi-transparent film (HTL), the light shielding film (CR), and the antireflection film (AR) are patterned can be formed. (See FIG. 8 (e)).

In the manufacturing process of the photomask having the film configuration shown in FIG. 9, a transparent substrate (FIG. 9 (FIG. 9 (A)) is laminated in the order of a semi-transparent film (HTL), a Cr-based light-shielding film (CR), and an antireflection film (AR). a)), a first resist coating is performed to form a resist film, and pattern exposure and development are performed on the resist film to form a first resist pattern (see FIG. 9B). Thereafter, by etching using this resist pattern as a mask, a photomask intermediate in which the semi-transparent film (HTL), the Cr-based light shielding film (CR), and the antireflection film (AR) are patterned is formed (FIG. 9 ( c)).
Next, a second resist coating is performed on the photomask intermediate to form a resist film, and pattern exposure and development are performed on the resist film to form a second resist pattern (see FIG. 9D). . Thereafter, by etching using this resist pattern as a mask, a photomask or photomask intermediate in which a semi-transparent film (HTL), a Cr-based light shielding film (CR), and an antireflection film (AR) are patterned is formed. (See FIG. 9E).

In any of the manufacturing methods shown in FIGS. 8 and 9, the coating method using the drying means 100 is applied in resist coating.
Here, in a photomask, discharge may occur due to a potential difference due to static electricity, and the optical film may be damaged due to the energy at that time. In particular, a plurality of optical films formed on a substrate may be patterned. In doing so, during the second patterning, a discharge may occur between patterns of optical films such as light-shielding films that have already been patterned, and the pattern shape may be damaged. In particular, when a pattern with a sharp tip is approaching, electrostatic breakdown is likely to occur. In FIG. 8C and FIG. 9C, there is a possibility that discharge occurs between the Cr-based light shielding film (CR) patterns adjacent to each other with a space therebetween, resulting in electrostatic breakdown.

  At this time, since the air flow parallel to the substrate can be supplied by the drying means 100, the air current is supplied to the Cr-based light-shielding film (CR) by supplying an air flow having an appropriate humidity (for example, humidity 40 to 70%). Therefore, electrostatic breakdown can be prevented in advance. In the clean room, the atmosphere itself is already controlled to the humidity. However, as described above, humidification means may be provided in order to give the airflow an appropriate humidity.

  Embodiments of the resist coating method and the resist coating apparatus, and the photomask blank and the photomask manufacturing method using the resist coating method according to the present invention are not limited to the above-described embodiments, but various other implementations. Forms are included in the present invention.

DESCRIPTION OF SYMBOLS 1 Application | coating apparatus 2 Application | coating means 3 Adsorption means 4 Moving means 5 Holding means 9 Linear gauge 10 Substrate 10a Coating surface 11 Base frame 12 Moving frame 13 Moving part 20 Coating liquid 21 Support plate 22 Elevating part 23 Capillary gap 24 Nozzle 25 Liquid tank 26 Nozzle Elevator 41 Linear Way 42 Ball Screw 43 Motor 55 Holding Member 61 Holding Plate 62 Linear Way 63 Rail 64 Linear Way 65 Rotating Plate 66 Rotating Shaft 67 Rotating Cylinder 68 Stopper 69 Base Plate 70 Holding Means Frame 71 Guide Rod 72 Bottom frame 73 Elevating means 91 Measuring terminal 100 Drying means 102 Air flow generation source 102a Drive unit 102b Blow nozzle 104 Current plate 104a Guide surface 106 Base member 108 Eaves part 110 Resist solution

Claims (14)

A method of applying a resist solution to a substrate with a surface to be coated facing downward,
The resist solution stored in the liquid tank is guided to the surface to be coated by capillary action of a nozzle to come into contact with the surface to be coated, and the nozzle and the substrate are moved relative to each other in the horizontal direction to thereby apply the surface to be coated. Apply a resist solution on the surface,
The coated resist solution is supplied by supplying an air flow parallel to the coated surface at a substantially constant relative flow rate in a certain direction with respect to the coated surface, and bringing the air flow into contact with the coated resist solution. A resist coating method, characterized by performing drying.   2. The resist coating method according to claim 1, wherein the air flow is rectified by a rectifying plate disposed to face the coated surface, and an air flow parallel to the coated surface is supplied.   3. The resist coating method according to claim 1, wherein, in the surface to be coated, a direction in which coating proceeds and a direction in which the air flow proceeds are the same direction.   By moving the substrate in the horizontal direction, the resist solution is applied to the surface to be coated, and the airflow is brought into contact with the applied resist solution in a direction opposite to the moving direction of the substrate. The resist coating method according to claim 3, wherein the resist coating method is characterized.   5. The resist coating method according to claim 1, wherein the supply of the airflow is started before the coating on the coated surface is completed.   The resist coating method according to claim 5, wherein the supply of the airflow is started before the application to the surface to be coated is started.   The resist coating method according to any one of claims 1 to 6, wherein a flow velocity of the airflow is 10 times or more with respect to a speed of the relative movement of the nozzle and the substrate.   The resist coating method according to claim 1, wherein a flow rate of the airflow is 0.05 to 1.5 m / sec.   It is a photomask blank manufacturing method including the process of apply | coating a resist to the photomask blank board | substrate with which the optical film was formed on the transparent substrate, Comprising: By the resist coating method of any one of Claims 1-8 A method for producing a photomask blank, comprising applying a resist.   A method of manufacturing a photomask by patterning a transfer pattern corresponding to an electronic device to be obtained on an optical film on a transparent substrate, wherein the photomask blank according to claim 9 is used. , Photomask manufacturing method. A method of manufacturing a photomask in which a plurality of optical films formed on a transparent substrate are respectively patterned,
Applying a resist, patterning the first optical film by performing a drawing and developing process on the resist, and forming a photomask intermediate having a first transfer pattern;
A photomask or photomask intermediate having a second transfer pattern by applying a resist to the photomask intermediate, patterning the resist, and developing the resist to pattern the second optical film. Forming a step;
Including
A method for producing a photomask, wherein the resist coating method according to any one of claims 1 to 8 is used for coating the resist. A resist coating apparatus for applying a resist solution to a substrate with a surface to be coated facing downward,
A coating means comprising: a liquid tank for storing a resist liquid; and a nozzle for guiding the resist liquid stored in the liquid tank to a surface to be coated of the substrate by capillary action;
Moving means for relatively moving both of the nozzle and the substrate in a horizontal direction by moving at least one of the nozzle and the substrate;
An airflow generation source for generating an airflow, and a rectifying plate that has a guide surface arranged to face the coated surface at a predetermined separation distance and rectifies the airflow into a flow parallel to the coated surface. A drying mechanism;
With
In the state where the resist solution is in contact with the coated surface by capillary action by the coating means,
The moving means applies the resist solution to the surface to be coated by relatively moving the nozzle and the substrate in a horizontal direction,
The drying means supplies an air flow parallel to the coated surface at a substantially constant relative flow velocity in a fixed direction with respect to the coated surface, and bringing the air flow into contact with the coated resist solution, A coating apparatus for drying a coated resist solution.
Resist coating device.   The coating apparatus according to claim 12, wherein the separation distance is adjustable, and the separation distance is adjusted according to a flow velocity of the airflow.   13. The substrate is moved in the horizontal direction by the moving means, whereby the nozzle and the substrate are relatively moved in the horizontal direction, and the air flow source is moved integrally with the substrate. Or the resist coating apparatus according to 13.