JP3779302B2 - Coating apparatus and coating method - Google Patents

Description

  The present invention is for forming a thin film by applying a predetermined coating liquid such as photoresist on the surface of various substrates such as semiconductor wafers, circular substrates such as disks, glass substrates for liquid crystals, square substrates such as photomasks, etc. The present invention relates to a coating apparatus and a coating method.

  Conventionally, various substrates such as a glass substrate for liquid crystal are placed on a rotatable chuck, a resist solution is dropped from above the substrate, and then the substrate is rotated together with the chuck so that the resist solution is centrifugally applied to the surface of the substrate. Various coating apparatuses (spin coaters) are known which spread over the entire surface and form a thin film having a uniform film thickness of the coating liquid on the entire surface of the substrate (see Patent Document 1).

JP-A-5-96222

  However, in the conventional coating apparatus, the amount of the resist solution remaining on the substrate surface at the stage of forming the resist film is very small compared to the amount of the resist solution dropped on the substrate surface. That is, most of the dropped resist solution is scattered from the substrate surface by centrifugal force and does not contribute to the formation of the resist film, and much of the resist solution is wasted.

  In order to solve such a problem, for example, if the amount of the resist solution dropped on the substrate surface is reduced, another problem arises that the resist solution does not spread over the entire substrate surface and a uniform thin film cannot be formed.

  Furthermore, if the number of rotations of the chuck that rotates with the substrate is reduced, the amount of the resist solution scattered from the substrate surface by centrifugal force can be reduced, but the thickness of the resist film formed on the substrate surface can be increased. This results in non-uniformity and causes another problem that a resist thickness having a desired quality cannot be formed.

  Therefore, the present invention can reduce the consumption of a resist solution and other coating solutions used for forming a thin film, and can form a thin film having a desired film thickness that is uniform over the entire substrate surface. It is an object of the present invention to provide a coating apparatus and a coating method capable of performing the above.

  The coating apparatus according to claim 1 is a coating apparatus that forms a thin film on the surface of the substrate by supplying a predetermined coating solution to the surface of the substrate, and a holding means for holding the substrate, and a surface of the substrate held by the holding means. An elongated nozzle that supplies the coating liquid to the substrate, a loader that moves the elongated nozzle parallel to the surface of the substrate, a cleaning device that cleans the elongated nozzle, and a movement that allows the cleaning device to move in the longitudinal direction of the elongated nozzle. And a mechanism.

  In the coating apparatus according to the first aspect, the elongated nozzle is moved in parallel with the substrate by a loader, thereby applying to a predetermined region of the substrate. The elongated nozzle is cleaned by a cleaning device, and the coating liquid adhering to the elongated nozzle is cleaned. The cleaning device moves and moves in the longitudinal direction of the elongated nozzle by the moving mechanism.

  The coating apparatus according to claim 2 is characterized in that the cleaning device includes a roller for cleaning the elongated nozzle.

  In the coating apparatus of claim 2, the elongated nozzle is cleaned by the roller.

The coating apparatus according to claim 3 is a coating apparatus that forms a thin film on the surface of the substrate by supplying a predetermined coating solution to the surface of the substrate, and a holding means for holding the substrate, and a surface of the substrate held by the holding means. An elongated nozzle that supplies the coating liquid to the substrate, a loader that moves the elongated nozzle in parallel with the surface of the substrate, and a cleaning device that cleans the elongated nozzle, and the cleaning device is supplied with a rinse solvent. And a movement mechanism capable of moving the cleaning nozzle in the longitudinal direction of the elongated nozzle .

  In the coating apparatus according to the third aspect, the elongated nozzle is moved in parallel with the substrate by a loader, thereby applying to a predetermined region of the substrate. The elongated nozzle is cleaned by a cleaning nozzle supplied with a rinse solvent. The rinse solvent at the time of washing is drained by suction from the drain exhaust pipe.

The coating apparatus according to claim 4 is characterized in that the cleaning device further includes a drying nozzle to which N ₂ is supplied under pressure.

In the coating apparatus of claim 4, the elongated nozzle is dried with N ₂ from the drying nozzle after washing.

The coating apparatus according to claim 5 is characterized in that, in the cleaning apparatus, the rinse solvent cleaning nozzle and the N ₂ drying nozzle are combined.

In the coating apparatus of the fifth aspect, in the cleaning apparatus, the rinse solvent cleaning nozzle and the N ₂ drying nozzle are combined.

The coating method according to claim 6 is a coating method in which a predetermined coating solution is supplied to the surface of the substrate to form a thin film on the surface of the substrate, and is moved while supplying the coating solution to the elongated nozzle on the surface of the substrate. A coating liquid supply process for supplying a coating liquid to a predetermined area; and a cleaning process for supplying a rinse solvent from the cleaning nozzle to the elongated nozzle and cleaning the movable nozzle while moving the cleaning nozzle in the longitudinal direction of the elongated nozzle. It is characterized by providing.

In the coating method according to the sixth aspect , on the surface of the substrate, the coating liquid is supplied to a predetermined area by being moved while supplying the coating liquid to the elongated nozzle. The elongated nozzle is cleaned by being supplied with a rinsing solvent from a cleaning nozzle. The cleaning nozzle moves in the longitudinal direction of the elongated nozzle for cleaning.

The method of coating according to claim 7, pre-Symbol cleaning process, characterized in that it comprises a step of suction discharging the rinse solvent supplied.

The coating method according to claim 7, in washing step, rinsing solvent supplied is sucked drained.

The coating method according to claim 8 further includes a step of blowing the elongated nozzle to dry (drying).

In the coating method of claim 8 , the elongated nozzle is blown and dried.

The application method according to claim 9 is characterized in that the drying step includes a step of sucking and exhausting while blowing.

In the coating method according to the ninth aspect , suction and exhaust are performed while blowing in the drying step.

  In the coating apparatus according to the first aspect, waste of the coating liquid can be suppressed, and a cleaning apparatus for cleaning the portion of the elongated nozzle that contacts the coating liquid is further provided, so that a clean coating liquid can be always supplied. . Cleaning can be performed by moving the cleaning device in the longitudinal direction of the elongated nozzle by the moving mechanism.

  In the coating apparatus according to the second aspect, the elongated nozzle can be cleaned by the roller.

In the coating apparatus according to the third aspect, the waste of the coating liquid can be suppressed, and a cleaning apparatus for cleaning the portion of the elongated nozzle that contacts the coating liquid is further provided, so that a clean coating liquid can be always supplied. . The rinse solvent during cleaning can be sucked and discharged from the drain exhaust pipe. Further, the cleaning nozzle can be cleaned by moving in the longitudinal direction of the elongated nozzle by the moving mechanism.

In the coating apparatus according to the fourth aspect, after the long nozzle is washed, it can be dried by N ₂ from the drying nozzle.

In the coating apparatus according to the fifth aspect, the rinsing solvent cleaning nozzle and the N ₂ drying nozzle can be used in combination.

In the coating method according to claim 6 , waste of the coating liquid can be suppressed, and a portion in contact with the elongated nozzle coating liquid by supplying a rinsing solvent from the cleaning nozzle while moving the cleaning nozzle in the longitudinal direction of the elongated nozzle. As a result of washing, a clean coating solution can be supplied constantly.

The coating method according to claim 7, in washing processes, since the suction discharging the rinse solvent supplied, it is possible to always provide a clean coating solution.

In the application method of claim 8 , the elongated nozzle can be blown and dried.

In the coating method of claim 9 , suction and exhaust can be performed while blowing in the drying step.

  As shown in FIGS. 1 (a) and 1 (b), the coating apparatus of the first embodiment is a resist supply nozzle 4 that moves parallel to an edge 2a extending in the short direction of the glass substrate 2 for liquid crystal. A plate 6 serving as a resist expansion brush extending in parallel with the end side 2a, a plate loader 8 for moving the plate 6 in parallel with the end side 2b perpendicular to the end side 2a, and the liquid crystal glass substrate 2 And a chuck 9 that rotates together with the glass substrate 2 for liquid crystal after the supply / expansion of the resist.

  In this embodiment, since the liquid crystal glass substrate 2 to be held is a square shape, the upper surface of the chuck is also a square shape corresponding to the shape, and is configured to hold the entire substrate 2 as horizontally as possible. Yes. When holding a circular semiconductor wafer, a circular chuck may be used. Furthermore, it goes without saying that in order to hold the entire substrate as horizontally as possible, it is preferable to hold the vicinity of the edge by the chuck.

  The nozzle 4 can reciprocate in parallel with the end side 2 a in a section excluding both ends of one end side 2 a of the liquid crystal glass substrate 2. By discharging the resist solution 10 while moving the nozzle 4 in one direction, the resist solution 10 is dropped onto a region that is close to the end side 2a and extends along the end side 2a.

  The plate 6 can be reciprocated in the longitudinal direction of the end side 2b while maintaining a regular interval t with the liquid crystal glass substrate 2 so that the lower end thereof is parallel to the end side 2a. The plate 6 is moved close to the surface of the liquid crystal glass substrate 2 and moved in the longitudinal direction of the edge 2b, so that a predetermined area on the surface of the liquid crystal glass substrate 2 is applied prior to the entire surface application of the resist solution 10 to the substrate 2. That is, the resist solution 10 is extended to a surface region (hereinafter referred to as “pre-coating region”) that is maintained at a predetermined distance or more from the periphery on the liquid crystal glass substrate 2. In order to distinguish this process from the process of spreading the resist solution 10 over the entire substrate surface as will be described later, this process is referred to as “pre-coating”.

  The plate loader 8 reciprocates the plate 6 in the longitudinal direction of the end side 2 b of the liquid crystal glass substrate 2. Although not shown, the plate loader 8 can reciprocate in the vertical direction, and the distance t between the lower end of the plate 6 and the liquid crystal glass substrate 2 can be adjusted as appropriate.

  The chuck 9 rotates together with the liquid crystal glass substrate 2 on which the resist solution 10 has been pre-coated after the plate loader 8 has retracted from the vicinity of the liquid crystal glass substrate 2, and the resist solution 10 is applied to the entire surface of the liquid crystal glass substrate 2. Spread to.

  Hereinafter, based on FIG. 2, operation | movement of the coating device of 1st Example is demonstrated.

  As shown in FIG. 2A, the resist solution 10 is discharged from the nozzle 4 while scanning the nozzle 4 in the front-rear direction of the drawing (direction perpendicular to the paper surface). As a result, the resist solution 10 is dropped onto a region that is close to the edge 2a of the glass substrate 2 for liquid crystal and extends along the edge 2a.

  As shown in FIG. 2 (b), the plate 6 is brought close to the liquid crystal glass substrate 2, and the resist solution 10 dripped onto the liquid crystal glass substrate 2 is scraped out in the left direction of the drawing, A resist solution 10 is pre-applied to the pre-application area. The scanning speed of the plate 6 at this time needs to be appropriately changed according to the interval t between the lower end of the plate 6 and the glass substrate 2 for liquid crystal. The interval t needs to be as small as possible because it is necessary to apply the resist solution 10 as thinly as possible, but it is difficult to reduce the interval t to some extent due to the mechanism. Accordingly, the scanning speed of the plate 6 is increased as the interval t increases, and the resist solution 10 is spread while forming a sufficiently large resist pool 10a in front of the traveling direction of the plate 6, so that the resist solution 10 is spread sufficiently thinner than the interval t. be able to. In order to reduce the consumption of the resist solution 10, for example, the thickness of the resist solution 10 needs to be about 0.1 mm or less. In this case, the lower end of the plate 6 and the glass substrate 2 for liquid crystal are used. What is necessary is just to adjust the space | interval t to about 0.2-0.5 mm.

  As shown in FIG. 2C, after the plate 6 is moved to the left end of the liquid crystal glass substrate 2 in the drawing, the resist solution 10 is left for a while with the plate 6 fixed, and the surface of the resist solution 10 Wait for it to become flat due to its own weight (hereinafter referred to as “leveling process”). By this leveling process, the resist pool 10a formed at the lower end of the plate 6 is smoothed, and the next rescanning process in the opposite direction is ready.

  As shown in FIG. 2D, the plate 6 is reversely scanned to the right side of the drawing to further flatten the resist solution 10 on the liquid crystal glass substrate 2. This process and the leveling process in FIG. 2C are not necessarily required.

  FIG. 2E is a diagram showing a modification of the leveling process of FIG. If the plate 6 is moved so as to exceed the resist pool 10a, a quick leveling process can be performed, and the reverse scanning process of FIG. 2D is also effective.

  FIG. 3A is a plan view schematically showing the glass substrate 2 for liquid crystal on which the pre-application of the resist solution 10 has been performed. The peripheral edge 10b of the resist solution 10 applied to the pre-application area is kept at an equal distance a from the edges 2a, 2b of the liquid crystal glass substrate 2. By the pre-coating as shown in the figure, the peripheral edge 10b of the resist solution 10 is located at approximately the same distance from the end edges 2a, 2b of the liquid crystal glass substrate 2. By such a pre-coating step and a step of rotating the liquid crystal glass substrate 2 described later, the resist solution 10 can be spread almost uniformly to the edges 2 a and 2 b of the liquid crystal glass substrate 2. When the amount of the resist solution 10 dropped in order to suppress the consumption of the resist solution 10, the resist solution 10 becomes more difficult to spread uniformly as the interval a increases, and the resist solution 10 becomes thinner as the interval a decreases. Since it is necessary to apply, the interval a is appropriately set according to various standards such as the accuracy of the film thickness after application of the resist solution 10.

The distance a from the edges 2a, 2b of the liquid crystal glass substrate 2 to the peripheral edge 10b of the resist solution 10 is appropriately changed according to the size, the aspect ratio of the liquid crystal glass substrate 2, and the like. For example, when the pre-coating process is performed on the glass substrate for liquid crystal 2 having a size of 320 mm × 400 mm to 750 mm × 1000 mm, a is set in a range of 0 <a ≦ 60 mm under the first condition described below. Referring to FIG. 4, under the first condition, the acceleration is set to about 11.7 revolutions / second ² or more and the acceleration time is about 2.9 seconds or less in the accelerated spin process. In this spinning step, the rotation speed is 2000 rotations / minute and the rotation time is about 4.0 seconds. In the deceleration spin process, the deceleration is set to about 11.7 revolutions / second ² or more, and the deceleration time is set to about 2.9 seconds or less.

On the other hand, under a second condition different from the above, the acceleration is set to about 8.3 revolutions / second ² and the acceleration time is set to about 4.0 seconds in the acceleration spin process. In this spinning step, the rotation speed is 2000 rotations / minute and the rotation time is about 4.0 seconds. In the deceleration spin process, the deceleration is about 8.3 revolutions / second ² and the deceleration time is about 4.0 seconds.

  In a state where the pre-coating as described above is completed, the liquid crystal glass substrate 2 is rotated at a high speed together with the chuck 9 to spread the resist solution 10 over the entire surface of the liquid crystal glass substrate 2. In this state, the resist solution 10 on the liquid crystal glass substrate 2 is cured to form a resist film on the liquid crystal glass substrate 2.

  FIG.3 (b) is the top view which represented typically the glass substrate 2 for liquid crystals to which the different pre-application | coating was given from Fig.3 (a). In this case, the peripheral edge 10b of the resist solution 10 applied to the pre-application area and the edges 2a, 2b of the liquid crystal glass substrate 2 are similar. By the pre-coating as shown in the figure, the peripheral edge 10b of the resist solution 10 is located at an approximately equal distance from the end edges 2a and 2b of the liquid crystal glass substrate 2.

  Further, since the centrifugal force acting on the resist solution increases as the distance from the rotation center 2c of the liquid crystal glass substrate 2 becomes shorter, the width of the left and right uncoated areas is wider than the width of the upper and lower uncoated areas as shown in the figure. However, the consumption of the resist solution 10 can be reduced as a result.

  As described above, according to the coating apparatus of the first embodiment, the resist is applied to the pre-coating region having the peripheral edge 10b at substantially the same distance from the edges 2a, 2b of the liquid crystal glass substrate 2 toward the rotation center 2c. The liquid 10 is supplied to a substantially uniform thickness. Therefore, by rotating the liquid crystal glass substrate 2, the resist solution 10 pre-coated on the liquid crystal glass substrate 2 is spread evenly to the edges 2 a and 2 b, and the peripheral edge 10 b is almost on the outer periphery of the liquid crystal glass substrate 2. It can be reached at the same time. Therefore, the amount of the resist solution 10 scattered from the edges 2a and 2b of the liquid crystal glass substrate 2 by quickly stopping the rotation of the liquid crystal glass substrate 2 after the peripheral edge 10b reaches the outer periphery of the liquid crystal glass substrate 2. Thus, the waste of the resist solution can be suppressed, and a resist film having a uniform film thickness can be formed over the entire surface of the liquid crystal glass substrate 2. More specifically, the resist solution 10 used for the liquid crystal glass substrate 2 in the range of 320 mm × 400 mm to 750 mm × 1000 mm is about 20 cc in the conventional method, but can be reduced to about 10 cc in the embodiment.

  As shown in FIG. 5, the coating apparatus of the second embodiment includes an elongated nozzle 46 for supplying and expanding the resist. The loader that moves the elongated nozzle 46 parallel to the edge 2b of the liquid crystal glass substrate 2 and the chuck that holds and rotates the liquid crystal glass substrate 2 have the same configuration as in the first embodiment. Therefore, the description is omitted here.

  The elongated nozzle 46 includes a cavity 46a for storing the resist solution 10 and a slit 46b that is formed along the longitudinal direction of the elongated nozzle 46 and communicates with the cavity 46a. When the resist solution 10 is supplied under pressure from the resist supply pipe 46c, the resist solution 10 accumulated in the cavity 46a is discharged from between the slits 46b. Further, the elongated nozzle 46 can be reciprocated in the direction along the side edge 2b at an equal interval from the liquid crystal glass substrate 2 so that the lower end thereof is parallel to the side edge 2a of the liquid crystal glass substrate 2. It has become.

  Hereinafter, the operation of the coating apparatus of the second embodiment will be described. First, the liquid crystal glass substrate 2 is set on a chuck, and the elongated nozzle 46 is brought close to the edge 2 a of the liquid crystal glass substrate 2. Next, while supplying the resist solution 10 to the elongated nozzle 46, it is moved on the liquid crystal glass substrate 2 in a direction parallel to the edge 2b. Thus, the resist solution 10 is pre-applied to the pre-application region on the liquid crystal glass substrate 2 (see FIG. 6). The pre-application area at this time is the same as that shown in FIGS. 3 (a) and 3 (b). Next, the elongated nozzle 46 is retracted, the liquid crystal glass substrate 2 is rotated at a high speed together with the chuck 9, and the resist solution 10 is spread over the entire surface of the liquid crystal glass substrate 2. Thereafter, the resist solution 10 on the liquid crystal glass substrate 2 is cured to form a resist film on the liquid crystal glass substrate 2.

  In this case, the scanning speed of the elongated nozzle 46 needs to be slower than that of the plate 6 in FIG. The reason is that by moving the elongated nozzle 46 while maintaining the state where the meniscus of the resist solution 10 is formed at the lower end of the elongated nozzle 46, the resist solution 10 is not supplied, that is, a portion where the resist solution 10 is not supplied is generated. This is to prevent it from occurring. For example, in the case of a 360 mm × 465 mm liquid crystal glass substrate 2, the distance between the elongated nozzle 46 and the liquid crystal glass substrate 2 is maintained at about 0.2 mm to 0.5 mm, and the supply amount of the resist solution 10 is about 1 cc / second. By setting the scanning speed to about 42 mm / second, a uniform layer of the resist solution 10 having a thickness of about 0.1 mm can be pre-coated on the liquid crystal glass substrate 2.

  When the elongated nozzle 46 as shown in FIG. 6 is used, the arbitrary shape of the pre-coating region on the liquid crystal glass substrate 2 is increased. Since the resist solution is supplied from the elongate nozzle 46 itself, by adding an element such as rotation to the movement of the elongate nozzle 46, the position of the peripheral edge 10b is set at an approximately equidistant position from the edges 2a, 2b of the liquid crystal glass substrate 2. If necessary, the distance from the rotation center 2c of the liquid crystal glass substrate 2 to the end sides 2a, 2b is increased, and the distance between the end sides 2a, 2b and the peripheral edge 10b is slightly set in consideration of centrifugal force. The resist solution 10 can be supplied almost uniformly to the pre-coating regions of various shapes which are wide.

  In the first embodiment shown in FIGS. 1 to 4, the resist solution 10 is supplied along the short side 2 a of the rectangular liquid crystal glass substrate 2 to scan the plate 6 in the longitudinal direction of the substrate 2. In the second embodiment shown in FIGS. 5 and 6, the elongated nozzle 46 having a length corresponding to the edge 2 a in the short direction of the substrate 2 is scanned in the longitudinal direction of the substrate 2. Although the resist solution 10 is supplied to the substrate 2, the present invention is not limited to this. That is, in order to shorten the scan distance between the plate 6 and the elongated nozzle 46 and reduce the time required to supply the resist solution 10, it is better to set the scan direction to the short direction of the rectangular substrate 2. good.

  For example, when the resist solution 10 is supplied to the pre-coating region as shown in FIG. 7, the periphery 10b of the resist solution 10, that is, the outer periphery of the pre-coating region is the center of rotation from the edges 2a and 2b of the liquid crystal glass substrate 2. It is positioned exactly equidistant towards 2c.

  As shown in FIG. 8, the coating apparatus of the third embodiment is for applying a resist solution to a circular semiconductor wafer or the like. The coating apparatus includes a resist supply nozzle 84 that moves in the radial direction (radial direction) of the semiconductor wafer 82, a resist expansion plate 86 that extends along the radial diameter (radius) of the semiconductor wafer 82, and the semiconductor wafer. And a chuck (only the rotary shaft 89 is shown) that rotates with the semiconductor wafer 82 after the resist solution is supplied and expanded.

  Since the present embodiment is an apparatus for applying a resist solution to a circular semiconductor wafer, the upper surface of the chuck is circular as described above, and the entire wafer is horizontally supported by supporting it from below to the vicinity of the edge of the wafer. Configured to hold.

  As shown in FIG. 9A, the resist solution 10 is discharged from the nozzle 84 while moving the nozzle 84 linearly from the position close to the edge of the semiconductor wafer 82 toward the center. As a result, the resist solution 10 is dropped onto a substantially rectangular elongated region extending in the diameter direction of the semiconductor wafer 82. The moving direction of the nozzle 84 may be from the center of the semiconductor wafer 82 toward the edge.

  As shown in FIG. 9B, the plate 86 is moved onto the semiconductor wafer 82, brought close to the surface thereof, and the semiconductor wafer 82 together with the chuck is rotated at a low speed. When the semiconductor wafer 82 is rotated once or more, the resist solution 10 is pre-applied almost uniformly to the circular pre-application region on the semiconductor wafer 82. The rotation of the semiconductor wafer 82 at this time is maintained at a rotation speed of about 5 rotations / minute for 3.0 seconds after acceleration of about 0.5 seconds. The rotation speed and rotation time of the semiconductor wafer 82 are appropriately changed according to the distance between the lower end of the plate 86 and the semiconductor wafer 82, the amount of the resist solution 10 dropped, and the like.

  The steps shown in FIGS. 9A and 9B can be performed simultaneously. That is, by using the elongated nozzle 46 as shown in FIG. 5 instead of the plate 86 and rotating the semiconductor wafer 82 or the elongated nozzle 46 itself while dropping the resist solution 10 from the slit 46b, the semiconductor wafer 82 is rotated. The resist solution 10 is pre-applied almost flatly to the circular pre-application region. The pre-coating region has a peripheral edge at a substantially equidistant position from the edge of the semiconductor wafer 82 toward the center of rotation.

  Finally, the plate 86 is retracted from above the semiconductor wafer 82, and the semiconductor wafer 82 is rotated at a high speed. In this high-speed rotation, the rotation speed is increased by about 2.4 seconds, the rotation speed of about 1200 rotations / minute is maintained for 19.0 seconds, the rotation speed is decreased by about 2.4 seconds, and the rotation of the semiconductor wafer 82 is stopped. By this high speed rotation, the resist solution 10 is spread over the entire surface of the semiconductor wafer 82 and the spin coating process is completed.

  FIG. 10 is a graph showing the number of rotations of the chuck in the spin coating of the resist solution shown in FIG.

  In the coating apparatus according to the first to third embodiments described above, the resist solution 10 remains at the lower end of the plate 6 or the elongated nozzle 46 in which the resist solution 10 is expanded in the pre-coating process, and this is dried to generate particles. This may cause Therefore, it is necessary to clean the resist solution 10 adhering to the plate 6 and the elongated nozzle 46. Hereinafter, a cleaning apparatus for the resist solution 10 will be described.

  FIGS. 11A and 11B are a side view and a plan view, respectively, showing the plate 6 of the coating apparatus of the first embodiment and the cleaning apparatus 100 for cleaning the same. The cleaning apparatus 100 includes a pair of felt rollers 3 and 3 that removes the resist solution 10 attached to the lower end 6b of the plate 6 in the pre-coating process to prevent generation of particles, and both rollers 3 and 3. And a solvent pot 5 to be cleaned. The surface of the lower end portion 6b of the plate 6 that comes into contact with the resist solution 10 is formed of a smooth fluorine-based resin having high water repellency.

  The operation of the cleaning apparatus 100 will be described. First, the plate 6 is sandwiched between a pair of felt rollers 3 and 3 that rotate in opposite directions and moved from end to end of the plate 6 to wipe off the resist solution 10. Thereafter, the rollers 3 and 3 are rotated in the cleaning solvent pot 5 to elute the resist solution into the rinsing solvent, and are rotated outside the solvent pot 5 to shake off the rinsing solvent. Wash. When the rinse solvent in the solvent pot 5 becomes dirty, the rinse solvent is discharged from the drain and a new rinse solvent is replenished.

  However, with such a cleaning method, it is difficult to clean the plate 6 completely. In order to clean the plate 6, the rinsing solvent in the solvent pot 5 must be changed many times, and a large amount of rinsing solvent is required.

12 (a) and 12 (b) are a side view and a plan view showing a cleaning device obtained by improving the cleaning device of FIG. The cleaning device 200 includes a mini nozzle 7 having a large number of divided pore nozzles, an indirect pressure tank 17 made of stainless steel for supplying a rinse solvent for cleaning and N ₂ for blowing to the mini nozzle 7, and a mini nozzle. 7 includes a nozzle loader 37 that moves the plate 7 along the plate 6, and a solvent pot 47 that receives a rinse solvent that drops from the lower end 6 b of the plate 6 during cleaning.

  The mini nozzle 7 includes a pair of nozzle portions 7 a and 7 b that face each other with the plate 6 interposed therebetween. Each of the nozzle portions 7 a and 7 b includes about seven fine nozzles, and these fine nozzles are inclined obliquely so that the tip thereof faces the lower end portion 6 b of the plate 6. The nozzle portions 7 a and 7 b are fixed to each other by a fixing arm 7 c connected to the nozzle loader 37. The number of pore nozzles formed in each of the nozzle portions 7a and 7b was appropriately changed within the range of about 1 to 10 depending on the size of the plate 6 and the like.

The indirect pressure tank 17 is filled with a rinsing solvent (for example, ethyl lactate EL). This indirect pressurization tank 17 is connected to a pressurization N ₂ source via a regulator 57. The indirect pressurization tank 17 is connected to the mini nozzle 7 via an N ₂ valve V1 and an EL valve V2.

  The nozzle loader 37 reciprocates the pair of nozzle portions 7 a and 7 b in the longitudinal direction of the plate 6 via the fixed arm 7 c.

  The solvent pot 47 receives the rinse solvent dripped from the lower end portion 6 b of the plate 6. The rinse solvent accumulated in the solvent pot 47 is discharged from the drain.

Hereinafter, the operation of the cleaning apparatus of FIG. 12 will be described. First, after the resist solution is expanded by the plate 6, the plate loader 8 is operated to retract the plate 6 onto the solvent pot 47. Next, the valve V1 is connected to the indirect pressure tank 17 side, the valve V2 is opened, and the rinse solvent is pressurized and supplied from the indirect pressure tank 17 to the mini nozzle 7. In this state, the mini nozzle 7 is scanned in one direction to clean the lower end portion 6b of the plate 6 from both sides. That is, the resist solution adhering to the plate 6 is washed away cleanly by the rinse solvent ejected from the fine nozzle of the mini nozzle 7. Thereafter, the valve V1 is connected to the mini nozzle 7 side, the valve V2 is closed, and N ₂ is pressurized and supplied to the mini nozzle 7. In this state, the mini nozzle 7 is scanned in the reverse direction to dry the lower end 6b of the plate 6. Finally, the washed resist and rinse solvent are collected in the solvent pot 47. If the rinsing solvent is easy to dry, the N ₂ blowing step is not necessary.

  According to the cleaning apparatus of FIG. 12, since the rinse solvent is directly jetted onto the plate 6 to clean the plate 6, the cleaning effect can be enhanced and the amount of the rinse solvent used can be reduced. In addition, since there are no parts such as rollers that accumulate dirt, the number of replacement parts can be reduced and maintenance-free can be achieved.

FIGS. 13A and 13B are a plan view and a front view, respectively, showing another improved example of the cleaning device. This cleaning apparatus is an integrated type of cleaning and drying nozzles and a solvent pot, and is divided into a large number of divided fine nozzles 67a and sprayed from the fine nozzles 67a to the lower end portion of the plate 6 from the lower end portions. It comprises a large nozzle 67 having a solvent pot portion 67b for receiving the rinse solvent to be dropped. The large nozzle 67 is moved so as to wrap the plate 6 from the lower side of the plate 6, for example. Thereafter, a rinsing solvent is supplied to the large nozzle 67 while the large nozzle 67 and the plate 6 are relatively swung in the longitudinal direction, and the resist solution adhering to the plate 6 is washed away. The washed resist solution and the rinsing solvent are accumulated in the solvent pot portion 67b and discharged from the drain. Thereafter, N ₂ is pressurized and supplied to the large nozzle 67 while the large nozzle 67 and the plate 6 are relatively swung, and the rinse solvent on the plate 6 is dried.

In this case, an exhaust pipe can be connected to the side wall of the solvent pot portion 67b of the large nozzle 67 at an appropriate interval so that the rinse solvent does not scatter. Further, when the rinse solvent is easy to dry, the N ₂ blowing step is not necessary.

FIG. 14 is a plan view and a front view of still another improved example of the cleaning apparatus. This cleaning apparatus has an independent system for cleaning and drying nozzles. When supplying a rinsing solvent to the cleaning nozzle 77a, the rinsing solvent containing the resist solution is sucked and cleaned by a drain exhaust pipe 77c. when supplying N ₂ to use the nozzle 77a sucks the N ₂ containing rinsing solvent drainage exhaust pipe 77c.

  FIG. 15 is a cross-sectional view showing the elongated nozzle 46 of the coating apparatus of the second embodiment and a cleaning apparatus for cleaning the same. In this cleaning device, the lower end of the elongated nozzle 46 is cleaned with a pincushion type roller 43 with less dust generation.

  First, the bobbin roller 43 is brought into contact with the lower end of the elongated nozzle 46 while rotating. In this state, the pincushion roller 43 is moved relatively in the longitudinal direction of the elongated nozzle 46 to wipe off the resist solution at the lower end of the elongated nozzle 46. Thereafter, the pincushion roller 43 is washed by rotating the pincushion roller 43 in a solvent pot containing an appropriate rinsing solvent, and immediately after rotating it outside the solvent pot to shake off the rinse solvent. When the rinse solvent in the solvent pot 5 becomes dirty, it is replaced with a new rinse solvent.

  However, with such a cleaning method, it is difficult to clean the elongated nozzle 46 completely, and a large amount of rinse solvent is required. Further, since the slit 46b is formed at the lower end of the elongated nozzle 46, the lower end of the elongated nozzle 46 is difficult to remove and the resist solution near the slit 46b may be contaminated.

  FIGS. 16A and 16B are a front view and a side view, respectively, of a cleaning device obtained by improving the cleaning device of FIG. This cleaning apparatus includes a suction nozzle 87 having a cleaning nozzle 87a, a drying nozzle 87b, and a drainage exhaust pipe 87c. The suction nozzle 87 moves reciprocally in the longitudinal direction of the elongated nozzle 46 in the vicinity of the lower end of the elongated nozzle 46 by a moving mechanism (not shown).

First, after the pre-application of the resist solution by the elongated nozzle 46 is completed, a rinse solvent is supplied under pressure to the cleaning nozzle 87a. In this state, the rinsing solvent is sucked and drained while the suction nozzle 87 is scanned in one direction to clean the lower end of the elongated nozzle 46. As a result, the resist solution adhering to the elongated nozzle 46 is washed away with the rinse solvent. Thereafter, N ₂ is pressurized and supplied to the drying nozzle 87b. In this state, the lower end of the suction nozzle 87 scans in the opposite direction to the elongate nozzle 46 N ₂ blown with N ₂ was aspirated exhaust while to dry the lower end of the elongate nozzle 46.

  Note that the rinse solvent is not limited to one type. Therefore, a plurality of rinse solvents can be switched and supplied to the cleaning nozzle 87a, or a plurality of types of cleaning nozzles 87a can be provided to supply the plurality of rinse solvents simultaneously or individually. Further, the N2 blow from the drying nozzle 87 b may be only on the lowermost surface of the elongated nozzle 46. This is because the rinse solvent hardly accumulates in the other portions.

  According to the cleaning apparatus of FIG. 16, since the rinse solvent is directly jetted to the elongated nozzle 46 for cleaning, the cleaning effect can be enhanced and the amount of the rinse solvent used can be reduced. In addition, since there are no parts such as rollers that accumulate dirt, the number of replacement parts can be reduced and maintenance-free can be achieved.

In the cleaning apparatus shown in FIGS. 14 and 16, the cleaning rinse liquid and the drying N ₂ are configured to be supplied through separate pipes, whereby the rinse liquid and N ₂ are supplied. Cleaning and drying can be performed at the same time by moving the nozzle while supplying them simultaneously. However, when it is not necessary to perform cleaning and drying at the same time, the rinsing liquid and N ₂ are selectively supplied by using a nozzle for the rinsing liquid and a nozzle for N ₂ and providing a switching mechanism in the pipe. It can also be configured as follows.

  In the coating apparatus according to the embodiment described above, in a coating apparatus that supplies a predetermined coating solution to the surface of the substrate and rotates the substrate to form a thin film on the surface of the substrate, the substrate is held horizontally and held rotatably. The holding means, and a coating liquid supply means for supplying the coating liquid to a predetermined region having an outer circumference equidistant from the outer circumference on the surface of the substrate held by the holding means. Accordingly, the coating liquid supply means supplies the coating liquid to a predetermined area having an outer circumference equidistant from the outer circumference on the surface of the substrate held by the holding means. Therefore, by rotating the substrate supplied with the coating liquid, The coating liquid supplied to a predetermined area on the substrate surface can be spread almost uniformly to the edge of the substrate. That is, since the coating liquid is supplied to the predetermined area on the substrate surface prior to the rotation of the substrate, when the substrate is rotated after the coating liquid is supplied, the periphery of the coating area where the coating liquid exists is substantially uniform. spread. As a result, the amount of the coating liquid scattered from the edge of the substrate can be reduced, and waste of the coating liquid can be suppressed.

  In addition, the coating liquid supply means includes means for supplying the coating liquid to a predetermined region having an outer circumference equidistant from the outer periphery toward the rotation center of the holding means on the surface of the substrate held by the holding means. Therefore, the coating liquid supply means supplies the coating liquid to a predetermined area having an outer circumference equidistant from the outer periphery toward the rotation center of the holding means on the surface of the substrate held by the holding means. When the substrate is rotated, the peripheral edge of the coating region where the coating liquid exists is spread almost uniformly, and the coating liquid spreads over the entire surface of the substrate so as to reach the edge of the substrate almost simultaneously. As a result, the amount of the coating liquid scattered from the edge of the substrate can be reduced, and waste of the coating liquid can be suppressed.

  Further, the coating liquid supply means includes a coating liquid dropping means for dropping the coating liquid in a predetermined area on the substrate surface, and a coating liquid diffusion means for spreading the dropped coating liquid to the predetermined area on the substrate surface. Therefore, the coating liquid supply means has a coating liquid dropping means for dropping the coating liquid in a predetermined area on the substrate surface and a coating liquid diffusion means for spreading the dropped coating liquid on the predetermined area on the substrate surface. The liquid can be supplied to the predetermined area with a substantially uniform thickness, and the thickness of the coating liquid spreading over the entire substrate surface with the rotation of the substrate is kept substantially constant, and the film thickness is uniform over the entire substrate surface. A thin film can be formed.

  The coating liquid diffusing unit includes a coating liquid expanding mechanism that moves in parallel with the surface of the substrate held by the holding unit and expands the coating liquid dropped onto the substrate surface. Accordingly, the coating solution can be supplied in a more uniform thickness within this predetermined region, and the coating solution spreading over the entire substrate surface with the rotation of the substrate can be kept constant and the film thickness can be uniform over the entire substrate surface. A thin film can be formed.

  Further, there is further provided a cleaning means for cleaning a portion of the coating liquid expansion mechanism that comes into contact with the coating liquid. Therefore, it is possible to always supply a clean coating solution.

  Further, in a coating method in which a predetermined coating liquid is supplied to the surface of the substrate and a thin film is formed on the surface of the substrate by rotating the substrate, the coating liquid is applied to a predetermined area having an outer periphery equidistant from the outer periphery on the surface of the substrate. And a coating solution diffusion step of spreading the coating solution supplied to the predetermined area over the entire surface of the substrate by rotating the substrate supplied with the coating solution in a horizontal plane. Therefore, the coating liquid supplied to a predetermined area on the substrate surface can be spread almost uniformly to the edge of the substrate. That is, since the coating liquid is supplied to the predetermined area on the substrate surface prior to the rotation of the substrate, when the substrate is rotated after the coating liquid is supplied, the periphery of the coating area where the coating liquid exists is spread almost uniformly. . As a result, the amount of the coating liquid scattered from the edge of the substrate can be reduced, and waste of the coating liquid can be suppressed.

  The coating liquid supply step includes a step of supplying the coating liquid to a predetermined region having an outer periphery that is equidistant from the outer periphery toward the rotation center in the coating liquid diffusion step on the surface of the substrate. Therefore, when the substrate is rotated after supplying the coating solution, the peripheral edge of the coating region where the coating solution exists is spread almost uniformly, and the coating solution spreads over the entire substrate surface so as to reach the edge of the substrate almost simultaneously. As a result, the amount of the coating liquid scattered from the edge of the substrate can be reduced, and waste of the coating liquid can be suppressed.

  The coating liquid supply process includes a coating liquid dropping process for dropping the coating liquid in a predetermined area on the substrate surface, and a process for spreading the dropped coating liquid in a predetermined area on the substrate surface. Accordingly, the coating solution can be supplied in a substantially uniform thickness within the predetermined region, and the coating solution spreading over the entire surface of the substrate as the substrate rotates can be maintained at a substantially constant thickness, so that a uniform film can be formed over the entire substrate surface. A thin film having a thickness can be formed.

  The present invention is for forming a thin film by applying a predetermined coating liquid such as photoresist on the surface of various substrates such as semiconductor wafers, circular substrates such as disks, glass substrates for liquid crystals, square substrates such as photomasks, etc. It is useful for a coating apparatus and a coating method.

It is a figure which shows the structure of the coating device of 1st Example. It is a side view explaining the pre-coating operation | movement of the coating device of FIG. It is a top view which shows the area | region pre-applied by the coating device of FIG. It is a graph explaining operation | movement of the coating device of FIG. It is a perspective view explaining the structure of the coating device of 2nd Example. It is the elements on larger scale explaining the pre-coating operation | movement of the coating device of FIG. It is a top view which shows the modification of the area | region pre-applied by the coating device of FIG. It is a perspective view which shows the structure of the coating device of 3rd Example. It is a perspective view explaining the pre-coating operation | movement of the coating device of FIG. It is a graph explaining operation | movement of the coating device of FIG. It is the side view and top view which show the washing | cleaning apparatus for the plate 6 of FIG. FIG. 7 shows another cleaning device for the plate 6 of FIG. 1. FIG. 6 shows a further cleaning device for the plate 6 of FIG. 1. FIG. 6 shows a further cleaning device for the plate 6 of FIG. 1. It is sectional drawing which shows the washing | cleaning apparatus for the elongate nozzle 46 of FIG. FIG. 6 shows another cleaning device for the elongated nozzle 46 of FIG. 5.

Explanation of symbols

2 Glass substrate for liquid crystal 4 Nozzle 6 Plate 8 Plate loader 9 Chuck 43 Wound roller 46 Elongated nozzle 82 Semiconductor wafer 84 Nozzle 86 Plate 87 Suction nozzle 87a Cleaning nozzle 87b Drying nozzle 87c Drainage exhaust pipe

Claims (9)

In a coating apparatus that forms a thin film on the surface of a substrate by supplying a predetermined coating solution to the surface of the substrate,
Holding means for holding the substrate;
An elongated nozzle for supplying the coating liquid onto the surface of the substrate held by the holding means;
A loader that moves the elongated nozzle parallel to the surface of the substrate;
A cleaning device for cleaning the elongated nozzle;
A moving mechanism capable of moving the cleaning device in the longitudinal direction of the elongated nozzle;
A coating apparatus comprising:   The coating apparatus according to claim 1, wherein the cleaning device includes a roller for cleaning the elongated nozzle. In a coating apparatus that forms a thin film on the surface of a substrate by supplying a predetermined coating solution to the surface of the substrate,
Holding means for holding the substrate;
An elongated nozzle for supplying the coating liquid onto the surface of the substrate held by the holding means;
A loader that moves the elongated nozzle parallel to the surface of the substrate;
A cleaning device for cleaning the elongated nozzle;
With
The cleaning device includes a cleaning nozzle to which a rinsing solvent is supplied, a drainage exhaust pipe for sucking and draining the rinsing solvent, and a moving mechanism capable of moving the cleaning nozzle in the longitudinal direction of the elongated nozzle. A characteristic coating apparatus. The coating apparatus according to claim 3, wherein the cleaning device further includes a drying nozzle to which N ₂ is supplied under pressure. Wherein the cleaning apparatus, the coating apparatus according to claim 4, characterized in that the combined and the cleaning nozzle for rinsing solvent and N ₂ for drying nozzle. In the coating method of forming a thin film on the surface of the substrate by supplying a predetermined coating solution to the surface of the substrate,
On the surface of the substrate, while supplying the coating liquid to the elongated nozzle, the coating liquid is moved to supply the coating liquid to a predetermined region; and
A cleaning step of supplying a cleaning solvent from the cleaning nozzle to the elongated nozzle and cleaning the moving nozzle while moving the cleaning nozzle in the longitudinal direction of the elongated nozzle;
A coating method comprising: The coating method according to claim 6, wherein the cleaning step includes a step of sucking and draining the supplied rinse solvent . The coating method according to claim 6 or 7, further comprising a drying step of blowing and drying the elongated nozzle . The coating method according to claim 8, wherein the drying step includes a step of sucking and exhausting while blowing .

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