JP5195010B2 - Coating apparatus, coating method, and storage medium - Google Patents

Description

The present invention relates to a coating apparatus and a coating method for coating a substrate with a coating liquid.

  In the semiconductor manufacturing process, there is a step of applying a coating solution onto a substrate, and as a method of applying, for example, a spin coating method can be mentioned. In this spin coating method, a substrate such as a semiconductor wafer or a glass substrate for LCD is adsorbed to a spin chuck which is a substrate holding unit, and a coating solution is supplied to the center of the substrate and rotated at a high speed to apply the coating solution to the substrate. It is a technique to spread on the surface. As the coating solution, a resist solution is typical, and in addition, a chemical solution for an insulating film containing a silicon oxide precursor is used.

As shown in FIG. 9, the coating apparatus used in the spin coating method is provided with a spin chuck 11 in a cup 10 having a waste liquid path 15 and an exhaust path 16 at the bottom, and a wafer W as a substrate on the spin chuck 11. The liquid rebound preventing portion 2 is formed in an annular shape so as to face and oppose the peripheral edge of the back surface of the cup 10, and the mist that is shaken off when the wafer W is rotated by the spin chuck 11 is sucked by the exhaust passage 15. The liquid is drawn downward and discharged from the waste liquid passage 15. A space closer to the spin chuck 11 than the rebound prevention part 2 is partitioned from the outside by a partition part 22 continuous to the prevention part 2. Also, clean air is supplied to the lower side from a fan filter unit (FFU) 33 provided on the upper side of the coating apparatus. Therefore, the mist of the coating liquid shaken off by the centrifugal force due to the rotation of the wafer W is: The air is carried downward by a clean air stream formed in the cup 10 by suction of the exhaust passage 15, separated into gas and liquid, and discharged from the waste liquid passage 15.

  By the way, the bounce prevention unit 2 is provided so that the coating liquid colliding with the inner wall of the cup 10 does not bounce back to the back side of the substrate. Also, the space 23 on the inner side (spin chuck 11 side) has a negative pressure, so that the dispersed fine particles (mist) of the coating liquid are drawn into the reduced pressure space 23 and adhere to the back surface of the wafer W to become particles. In order to remove the particles, a process of supplying a solvent (back rinse) to the back surface of the wafer W from a nozzle provided on the back surface side of the wafer W is performed following spin coating. Since the amount used is several tens of ml, this back rinse is the process that consumes the most solvent in the liquid treatment including a series of coating treatment or development. For this reason, the total amount of the solvent used every month becomes a considerable amount, and it is desired to reduce the amount of the solvent used for the back rinse.

On the other hand, in Patent Document 1, a gap is formed in a partition portion around the spin chuck shaft and a shutter for opening and closing the gap is provided. An apparatus is described that eliminates the condition and reduces the adhesion of particles to the substrate. However, since the degree of negative pressure changes depending on the number of rotations of the substrate, for example, when the number of rotations is low, the degree of negative pressure is small, so if the shutter is opened widely, more gas than necessary will be released from the outside of the cup through the gap. It flows into the cup and affects the descending airflow, disturbing the airflow on the surface of the substrate, and as a result, the in-plane uniformity of the liquid film formed on the substrate may be impaired. Conversely, when the rotational speed is high, the degree of negative pressure is large, so if the shutter opening is small, the inflow of gas is small, so the negative pressure state is not eliminated and particle reduction is effective. It's hard to say.

JP-A-5-6855

  An object of the present invention is to provide a coating apparatus and a coating method that can reduce the adhesion of particles to the back surface of a substrate when a coating solution is applied to the substrate by a spin coating method, thereby reducing the amount of solvent used. It is to provide.

The coating apparatus of the present invention includes a cup placed in an atmosphere in which a downward airflow is formed, and an exhaust path connected to the lower portion of the cup for sucking and exhausting the atmosphere in the cup, and surrounded by the cup. The substrate is held horizontally on the substrate holding portion, and the coating liquid is supplied to the central portion of the substrate, and the substrate is rotated about the vertical axis through the substrate holding portion to spread the coating liquid on the surface of the substrate. In the device
In order to suppress the splash of the liquid to the back side of the substrate, it is provided in close proximity to the peripheral portion of the back surface of the substrate, and is formed in an annular shape in the circumferential direction of the substrate so as to protrude to the back side of the substrate A rebound prevention part,
A partition plate that is provided so as to continuously surround the rotating shaft of the substrate holding portion from the splash-preventing portion toward the center of the substrate, and forms a space partitioned from the lower external space of the cup on the back surface side of the substrate When,
This is more formed along the circumferential direction of the cup partition plate, an opening which communicates the lower side outer space on the back side of the space and the cup of the substrate surrounded by the partition plate,
An opening amount adjusting means comprising a shutter provided on the lower surface side of the partition plate in order to adjust each opening amount of the plurality of openings;
An exhaust amount adjusting means provided in the exhaust passage for adjusting the exhaust amount of the exhaust passage;
A control unit for controlling the opening amount adjusting means and the exhaust amount adjusting means according to the number of rotations of the substrate,
The control unit stores data corresponding to the opening amount of the opening and data corresponding to the exhaust amount for each rotation number of the substrate, and data corresponding to the rotation number of the substrate from the storage unit. And means for reading out and outputting each control signal of the opening amount adjusting means and the exhaust amount adjusting means.

In the coating method of the present invention, the substrate holding portion surrounded by the cup and the back surface of the substrate held by the substrate holding portion are opposed to the back surface peripheral portion of the substrate in order to suppress the splashing of the liquid. And a bounce prevention portion formed in an annular shape in the circumferential direction of the substrate so as to protrude to the back side of the substrate, and surrounding the rotation axis of the substrate holding portion continuously from the bounce prevention portion toward the center of the substrate provided to the partition plate forming a partitioned space relative to the lower side outer space of the cup on the back side of the substrate, a plurality of formed along the circumferential direction of the cup in the partition plate, surrounded by partition plate And an opening comprising a shutter provided on the lower surface side of the partition plate in order to adjust each opening amount of the plurality of openings. and amount adjusting means, the lower portion of the cup Is connected, using a coating apparatus equipped with an exhaust passage for sucking in the cup atmosphere,
Forming a downdraft in the atmosphere in which the cup is placed;
Holding the substrate horizontally on the substrate holding portion;
Supplying the coating solution to the center of the substrate and rotating the substrate around the vertical axis via the substrate holding unit to spread the coating solution on the surface of the substrate;
Data corresponding to the opening amount corresponding to the number of rotations of the substrate is referred to a storage unit storing data corresponding to the opening amount of the opening and data corresponding to the exhaust amount for each number of rotations of the substrate, and Reading data corresponding to the displacement from a storage unit by a computer;
And a step of controlling the opening amount and the exhaust amount based on the read data .

Still another invention is a storage medium for storing a computer program used in a coating apparatus that coats a rotating substrate with a coating liquid.
The computer program includes a group of steps for carrying out the coating method of the present invention.

  According to the present invention, by adjusting the opening amount of the opening of the partition that partitions the space on the back surface side of the substrate based on the rotation speed of the substrate, the suction is performed from the outside of the cup to the negative pressure space on the back surface of the substrate. Since the amount of gas is controlled, it is possible to reduce particles generated when the mist of the coating solution is drawn to the back side of the substrate. As a result, the amount of particles adhering to the back surface of the substrate can be reduced, and the amount of back rinse used can be reduced. Furthermore, since the adjustment of the exhaust amount in the exhaust path is also performed in conjunction with the adjustment of the opening amount, the turbulence of the air current around the substrate based on the intake of gas from the outside into the negative pressure space on the back surface side of the substrate is prevented. The film thickness profile of the film formed on the substrate is suppressed, and the variation in the film thickness profile between the substrates is small, so that stable processing can be performed.

FIG. 1 is a longitudinal sectional view showing an embodiment of a coating apparatus according to the present invention. This coating apparatus includes a spin chuck 11 that is a substrate holding unit that holds a wafer W as a substrate horizontally and vacuum-sucks it, and can be moved up and down by a rotation driving unit 12 via a shaft 11a, and a vertical axis. It can be rotated around. A cup 10 is provided so as to surround the wafer W on the spin chuck, and an opening 18 is formed on the upper portion of the cup 10 in a circular shape that is slightly larger than the wafer W so that the wafer W can be delivered. . An annular recess 19 is formed at the periphery of the opening 18 by being horizontally cut away from the inner peripheral surface thereof. The bottom surface 13 of the recess 19 is formed on the spin chuck 11. The height is set substantially the same as the held wafer W. The bottom surface 13 has a role of controlling the airflow generated by the rotating wafer W and making the resist film thickness at the peripheral edge of the wafer W uniform. Further, a communication passage 13a is formed vertically and downward from the bottom surface 13, and is connected to a liquid receiving portion 14 described later.

Further, the bottom of the cup 10 is configured as a liquid receiving part 14, and a waste liquid path 15 for discharging the waste liquid is connected to the liquid receiving part 14. Further, exhaust pipes 16a and 16b forming two exhaust passages are provided so as to enter the center side of the cup 10 from the liquid receiving portion 14, and gas-liquid separation is performed by the entry portions. The two exhaust pipes 16a and 16b merge downstream and are connected via a damper 17 to an exhaust duct in the factory (not shown). Therefore, the gas in the cup 10 is sucked by opening the damper 17, and the exhaust amount can be controlled by adjusting the opening degree.

Inside the cup 10, a guide portion 2 is provided in the vicinity of the peripheral edge of the back surface of the wafer W held by the spin chuck 11. The guide portion 2 is formed in a mountain shape by the inner inclined surface 21 and the outer inclined surface 26 and is formed in an annular shape along the circumferential direction of the wafer W, and constitutes a rebound preventing portion. Furthermore, a vertical wall 24 extending vertically and downward is provided at the outer end of the guide portion 2 so as to enter the liquid receiving portion 14. The guide unit 2 is for guiding the coating liquid shaken off from the wafer W to the liquid receiving unit 14 through the surface thereof and preventing the coating liquid from rebounding to the back surface of the wafer W. A horizontal surface 22 is provided inside the inclined surface 21 of the guide portion 2, and the inclined surface 21 and the horizontal surface 22 constitute a partition portion. A space partitioned from the lower external space of the cup 10 is formed on the back side of the wafer W by this partitioning portion. That is, an annular space surrounded by the inclined surface 21, the horizontal surface 22, the wafer W and the spin chuck 11 becomes the back side space 23 of the wafer W. Since the shaft portion 11 a of the spin chuck 11 passes therethrough, a slight gap is formed between the outer periphery of the spin chuck 11 and the horizontal plane 22. The back side space 23 is a space in which the atmosphere is decompressed by the rotation of the wafer W and the suction effect of the exhaust pipes 16a and 16b. Since the guide unit 2 corresponds to a bounce prevention unit, the part forming the space (back side space 23) partitioned on the back side of the wafer W can be regarded as including a bounce prevention unit. Since there is no hindrance in the explanation, it is assumed that the inclined surface 21 continuing to the upper end portion of the guide portion 2 and the horizontal surface 22 subsequent thereto correspond to the partition portion. Further, a back rinse nozzle 40 is provided in the vicinity of the outer edge of the horizontal surface 22, and the tip portion thereof is configured to face the outer peripheral edge of the wafer W. The back rinse nozzle 40 is connected to a back rinse supply source via a supply path (not shown).

The cup 10 is housed in a housing 30, and a transport port 31 for the wafer W is provided in the housing 30, and the wafer W can be transferred via the transport port 31 by a transport mechanism (not shown). It has become. In the figure, reference numeral 31 a denotes a shutter that opens and closes the transport port 31. The shutter 31a is closed except when the wafer W is carried into and out of the housing 30 by the transfer mechanism. In addition, a fan filter unit (FFU) 33 is provided on the upper portion of the housing 30, and the FFU 33 has a role of supplying clean gas, for example, clean air, flowing in through the gas supply path 32 to the housing 30 as a downward flow. . In the figure, the fan provided in the FFU 33 is omitted. A suction exhaust path 35 for exhausting the gas in the casing 30 is provided at the bottom of the casing 30. The downward flow from the FFU 33 and the suction by the exhaust pipes 16a and 16b combine to form a downward air flow in the opening 18 of the cup 10.

In the housing 30, a solvent nozzle 41 for discharging a solvent, a coating nozzle 42 for discharging a coating liquid, and a rinsing nozzle 43 for discharging a rinsing liquid are provided above the cup 10, and the nozzles 41, 42, 43 are Connected to the solvent supply source 51, the coating liquid supply source 52, and the rinsing liquid supply source 53 through supply pipes 41a, 42a, and 43a, respectively, and a predetermined position above the wafer W and a standby position on the side of the cup 10 It is configured to be moved by a transfer arm (not shown).

  An opening 25 penetrating downward is formed in the horizontal surface 22 of the guide member 2. For example, as shown in FIG. 2, the opening 25 is formed as a slit formed in an arc shape along a circle centered on the rotation center of the spin chuck 11, and is formed in the circle around the shaft portion 11 a of the spin chuck 11. Four places are provided at equal intervals along. The opening 25 serves to relieve the degree of negative pressure by allowing the gas from the lower space of the cup 10 to flow into the space 23 through the opening 25 when the back side space 23 is in a negative pressure state. It has something. Further, a replaceable filter 26 is detachably provided so that the inflowing gas does not contain dust or the like. Further, four shutter holding bases 63 are provided below the four openings 25, and the shutters 6 are respectively held on the holding bases 63, and the opening amount of the opening 25 is adjusted by the shutter 6. It is configured to be. Reference numeral 61 denotes a support rod, and 62 denotes a drive unit 62. The shutter 6 has an arc shape and a belt shape, and is configured to be slightly larger than the opening 25 so as to cover the opening 25 from below. The driving unit 62 can horizontally move the shutter 6 in the radial direction of the wafer W via the support rod 61, and the shutter 6 can adjust the opening amount of the opening 25 by this operation.

  Next, FIG. 3 schematically illustrates the control unit 7. The control unit 7 is configured by a computer and includes a data bus 70. In this computer, a computer program for performing the operation of the coating apparatus according to the embodiment of the present invention is installed via a storage medium such as a flexible disk, a hard disk, an MD, a memory card, and a compact disk. The data bus 70 includes a CPU 71, a program 72 stored in the storage unit 72a, a storage unit 73, a spin chuck motor 12, a shutter drive unit 62, a damper drive unit 76, a resist supply system 77, and a side rinse supply system 78. Etc. are connected. The resist supply system 77 and the side rinse supply system 78 are configured by valves and pumps for adjusting the liquid amount. The storage unit 73 stores data on the opening amount of the opening portion 25 and the gas exhaust amount for each rotation number of the wafer W or each coating recipe. For example, when the program 72 acquires the rotation speed data of the wafer W, the opening amount of the opening 25 and the data of the exhaust amount of gas can be acquired accordingly, and each data is transferred via the data bus 70 to the shutter drive unit 62 and The structure which can output to the drive part 76 for dampers, respectively is taken.

Next, the operation of the above embodiment will be described. The wafer W is loaded into the housing 30 using a transfer mechanism (not shown), and the spin chuck 11 is raised by, for example, the rotation drive unit 12, and the wafer W is placed on the spin chuck 11 and vacuum-sucked. Thereafter, the spin chuck 11 is lowered and the wafer W is accommodated in the cup 10. For example, three elevating pins may be provided so as to penetrate the horizontal plane 22, and the wafer W may be transferred by the three elevating pins. On the other hand, in the housing 30 and downdraft is formed as described above, at time t ₁ as shown in FIG. 4 (a), the wafer W for instance at a speed of 2000 (rpm) by the spin chuck 11 Rotate. Then, the above-mentioned descending air current spreads spirally toward the peripheral edge by the centrifugal force of the rotating wafer W. Then, the solvent nozzle 41 is moved from the standby position to the upper center of the wafer W by using a moving mechanism (not shown), the thinner is supplied from the solvent nozzle 41 to the wafer W, the surface of the wafer W is wetted with the thinner, and the resist solution extends. Prepare an easy environment (pre-wet). Then, pause the rotation of the wafer W at time t _2, the moving coating nozzle 42 with retracting the solvent nozzle 41 to the standby position to the top center of the wafer W.

The rotational speed was increased to 1500 (rpm) at time t ₃ to maintain this state for example 1,5 seconds, supplying the resist liquid from the coating nozzle 42 to the central portion of the wafer W therebetween. As shown in FIG. 5A, the resist solution R is extended outward by the centrifugal force generated by the rotation of the wafer W, and the excess resist solution R is shaken off from the surface of the wafer W. The resist solution R thus shaken off rides on the above-described descending airflow and flows between the communication path 13 a and the cup 10 and the guide member 2, is temporarily stored in the liquid receiving part 14, and from the waste liquid path 15. It is discharged to the outside of the cup 10. Then, the coating nozzle 42 that has finished coating the resist solution R is retracted to the standby position. After maintaining the rotational speed 1500 (rpm), dropped at time _{t 4} the rotational speed of the wafer W to 1190 (rpm), to form a dried resist solution R of the surface for 20 seconds the wafer W with the resist film.

Thereafter, Drop at time _{t 5} the rotational speed of the wafer W to 1000 (rpm), the side rinse nozzle 43 is moved onto the peripheral portion of the wafer W, the wafer W from the nozzle 43 as shown in FIG. 5 (b) The solvent which is the rinsing liquid is discharged toward the peripheral edge of the surface, the peripheral edge of the liquid film of the resist solution is cut with a predetermined width, and the solvent which is the rinsing liquid is removed from the back rinse nozzle 40 on the peripheral edge of the back surface of the wafer W. , And the resist solution that wraps around the back side of the wafer W is removed. Then, continuing to rotate the wafer W, after drying for 20 seconds a resist solution, and stops the rotation at time t _6, the wafer W is subjected to the transport mechanism in the reverse order to that at the time of loading of the aforementioned wafer W Passed out and carried out from the housing 30.
On the other hand, the control unit 7 reads out data corresponding to the opening degree of the shutter 6 and the damper 17 corresponding to the number of rotations of the wafer W from the storage unit 73, and based on this data, reads the data to the driving units 62 and 76 of the shutter 6 and the damper 17. Each outputs a control signal. Thereby, the opening degree of the shutter 6 and the damper 17 is controlled according to the rotation speed of the wafer W. The control unit 7 reads the time chart of the rotation number from the storage unit 73 according to the recipe when controlling the rotation number of the wafer W. Therefore, based on the read rotation number, the shutter 6 and the damper 17 are read from the storage unit 73. Although data corresponding to the opening degree may be read out, a detection unit for detecting the rotation speed of the spin chuck 11 is provided, and data corresponding to the opening degree is read out based on a detection value of the rotation speed from the detection unit. You may go.

An example of the operation of the shutter 6 and the damper 17 is shown in FIGS. 4B and 4C, respectively. From time t ₁ to t ₂ , the rotational speed is as high as 2000 (rpm), so the gas near the wafer W is shaken off outward by the centrifugal force due to the rotation, and the degree of negative pressure in the back space 23 is large. Accordingly, in response to this, the shutter 6 is opened wide, for example, the slit width of the opening 25 is set to 4 mm, and the amount of gas sucked into the decompressed back side space 23 is controlled. For this reason, the atmosphere of the back side space 23 is relaxed in the degree of negative pressure by the flowing gas. Further, the damper 17 opens widely so as to be able to suck the airflow shaken outward by the rotation of the wafer W and the above-described descending airflow, and is adjusted to an opening degree of 90%, for example.

Since the rotation of the wafer W is stopped from time t ₂ to t _3, the atmosphere in the back side space 23 is atmospheric pressure, the shutter 6 is closed, and the damper 17 is opened at, for example, an opening of 50%. Yes. Next, since the rotation speed of the wafer W is 1500 (rpm) from time t ₃ to t _4, the atmosphere in the back space 23 becomes negative pressure. For example, the slit width is 3 mm and the opening degree of the damper 17 is 75%. is adjusted, the same way from time _{t 4} to _{t 5} for the rotation speed of the wafer W is 1190 (rpm), for example, the slit width is 2.4 mm, the opening degree of the damper 17 is adjusted to 67%. Further, since from time _{t 5} to _{t 6} the rotational speed of the wafer W is 1000 (rpm), for example, the slit width is 2.0 mm, the opening degree of the damper 17 is adjusted to 58%, followed by a time _{t 6} Thereafter, since the wafer W is unloaded from the cup 10, the shutter 6 is closed and the opening degree of the damper 17 is controlled to 50% to suck down airflow inside the cup 10.

  Next, the gas flow inside the cup 10 will be described with reference to FIG. FIG. 6A shows a state where the shutter 6 is half open. In this case, the rotational speed of the wafer W is 1000 (rpm) from the time chart of FIG. 4, the slit width is 2 mm, and the opening degree of the damper 17 is 58%. The gas (air) D descending into the cup 10 spreads outward while being swirled by the rotation of the wafer W. The gas (air) G present in the back space 23 is pushed outward by the rotation of the wafer W, flows downward along with the gas D constituting the descending airflow, and is discharged from the exhaust pipe 16a. For this reason, the atmosphere of the back side space 23 will become a negative pressure, but an amount of gas U corresponding to the amount of the gas G discharged from the back side space 23 passes through the opening 25 from the lower external space of the cup 10. It flows into the space 23 and the negative pressure state is relaxed.

  FIG. 6B is a diagram showing a state where the shutter 6 is fully opened. At this time, the rotational speed of the wafer W is 2000 (rpm) from the time chart of FIG. 4, the slit width is 4 mm, and the opening degree of the damper 17 is 90%. Since the gas D has a high rotation speed of the wafer W, the gas D spreads outward while winding a stronger vortex than previously described, and the gas G existing in the back side space 23 is pushed outward more than in the previous case. The gas D flows downward along the cup 10 and is discharged from the exhaust pipe 16a. Then, the amount of gas G discharged from the backside space 23 increases as compared with the case where the rotation speed is 1000 (rpm), and the atmosphere of the space 23 tends to become a large negative pressure, but the slit width is wide as 4 mm. Therefore, the gas U corresponding to the amount of the gas G discharged from the back space 23 flows into the space 23 from the opening 25, and the negative pressure state is relaxed. At this time, the total amount of the gas U flowing into the cup 10 is larger than in the previous case, but the opening degree of the damper 17 in the exhaust passages 16a and 16b is set to be larger than that when the rotation speed of the wafer W is 1000 (rpm). Since the size is increased, the amount of gas drawn into the exhaust passages 16a and 16b from the periphery of the wafer W is substantially equal, and therefore, the airflow state on the surface of the wafer W is the same. Note that the numerical value of the opening degree of the damper 17 is a numerical value for convenience, and the amount of gas drawn into the exhaust passages 16a and 16b regardless of the rotation speed of the wafer W (regardless of the size of the slit width of the opening 25). Are set to match.

  On the other hand, FIG. 7 is a view showing the air flow inside the cup 10 when the opening degree of the damper 17 is fixed to 90% without interlocking the opening and closing of the shutter 6 and the damper 17. In this case, for example, when the rotation number of the wafer W is high and the opening degree of the shutter 6 is large, the amount of the gas G in the back side space 23 that is swung outward by the rotation of the wafer W is large. Is sucked from the exhaust pipe 16a. This is the same case as in FIG. However, when the rotation speed of the wafer W is low and the opening degree of the shutter 6 is small, the amount of the gas G in the back side space 23 that is swung outward by the rotation of the wafer W is higher than that when the rotation speed of the wafer W is high. A small amount of the gas G and the gas D are sucked from the exhaust pipe 16a. Accordingly, in this case, the suction effect works excessively on the gas D. As a result, the airflow near the surface of the wafer W is disturbed, which may affect the in-plane profile of the resist film thickness.

  According to the embodiment of the present invention described above, the opening and closing of the shutter 6 is controlled based on the number of rotations of the wafer W, and the amount of gas flowing into the space 23 is controlled by the degree to which the back space 23 of the wafer W is depressurized. The amount can be adjusted. Accordingly, since the air flow from the peripheral edge of the wafer W toward the space 23 is suppressed or no air flow is generated, the amount of particles adhering to the wafer W can be reduced, and as a result, the amount of back rinse used is reduced. It becomes possible to do. Further, by controlling the opening and closing of the shutter 6 and the damper 17 in conjunction with each other, the change in the airflow on the surface of the wafer W according to the opening degree of the shutter 6 can be suppressed, so that the airflow during the process is stabilized, resulting in a result. As described above, changing the opening degree of the opening 25 by the shutter 6 has little influence on the profile of the film thickness of the resist film, and stable processing can be performed. Since it is sufficient to adjust the damper 17 only in the process related to the film thickness profile, it is not necessary to adjust when the wafer W is pre-wet.

  Moreover, the shutter 6 can also take the structure which adjusts the opening amount of the opening part 25 by moving up and down. In this case, as shown in FIG. 8A, the shutter 6 has an elevating unit 64 instead of the driving unit 62, and the support bar 61 is inserted into the elevating unit 64. The elevating part 64 can move the shutter 6 up and down by raising and lowering the inserted support rod 63. This moving state is schematically shown in FIG.

It is a longitudinal cross-sectional view which shows the coating device which concerns on embodiment of this invention. It is a perspective view which shows typically the shutter which adjusts the opening part formed in the horizontal surface, and its opening amount. It is a block diagram which shows a control part. In embodiment of this invention, it is the figure which showed an example of the rotation speed of a wafer, opening amount, and the time chart of exhaust_gas | exhaustion amount. It is explanatory drawing which showed typically the mode of application | coating of the resist liquid to a wafer, and supply of a side rinse. It is explanatory drawing which showed typically the flow of the airflow inside a cup. It is explanatory drawing which showed typically the flow of the airflow inside a cup when not interlock | cooperating the motion of a shutter and a damper. It is explanatory drawing which shows other embodiment of a shutter typically. The schematic sectional drawing of the conventional coating device is shown.

Explanation of symbols

W Wafer 10 Cup 11 Spin chuck 12 Rotation drive part 16a, b Exhaust pipe 17 Damper 2 Guide part 23 Back side space 25 Opening part 34 Gas supply part 42 Application nozzle 6 Shutter 7 Control part R Resist solution

Claims (4)

A cup placed in an atmosphere where a downdraft is formed, and an exhaust passage connected to the lower portion of the cup for sucking and exhausting the atmosphere in the cup, and a substrate holding portion surrounded by the cup In a coating apparatus that spreads the coating liquid on the surface of the substrate by supplying the coating liquid to the central portion of the substrate and rotating the substrate around the vertical axis via the substrate holding section,
In order to suppress the splash of the liquid to the back side of the substrate, it is provided in close proximity to the peripheral portion of the back surface of the substrate, and is formed in an annular shape in the circumferential direction of the substrate so as to protrude to the back side of the substrate A rebound prevention part,
A partition plate that is provided so as to continuously surround the rotating shaft of the substrate holding portion from the splash-preventing portion toward the center of the substrate, and forms a space partitioned from the lower external space of the cup on the back surface side of the substrate When,
A plurality of openings formed in the partition plate along the circumferential direction of the cup, and an opening that communicates the space on the back side of the substrate surrounded by the partition plate and the external space below the cup;
An opening amount adjusting means comprising a shutter provided on the lower surface side of the partition plate in order to adjust each opening amount of the plurality of openings;
An exhaust amount adjusting means provided in the exhaust passage for adjusting the exhaust amount of the exhaust passage;
A control unit for controlling the opening amount adjusting means and the exhaust amount adjusting means according to the number of rotations of the substrate,
The control unit stores data corresponding to the opening amount of the opening and data corresponding to the exhaust amount for each rotation number of the substrate, and data corresponding to the rotation number of the substrate from the storage unit. Means for reading out and outputting respective control signals of the opening amount adjusting means and the exhaust amount adjusting means.   The coating apparatus according to claim 1, wherein a filter for removing particles is detachably provided in each of the plurality of openings. A substrate holding unit surrounded by a cup and a back surface of the substrate provided to face the back surface peripheral edge of the substrate in order to suppress splashing of liquid to the back surface side of the substrate held by the substrate holding unit. A rebound preventing portion that protrudes sideways and annularly formed in the circumferential direction of the substrate, and is provided so as to surround the rotation axis of the substrate holding portion continuously from the rebound preventing portion toward the center of the substrate, A partition plate that forms a space partitioned with respect to the external space below the cup on the back surface side of the cup, and a space on the back surface side of the substrate that is formed in the partition plate along the circumferential direction of the cup and is surrounded by the partition plate An opening communicating with the lower external space of the cup, an opening amount adjusting means comprising a shutter provided on the lower surface side of the partition plate for adjusting each opening amount of the plurality of opening portions, Connected to the bottom Using a coating apparatus equipped with an exhaust passage for sucking the internal atmosphere,
Forming a downdraft in the atmosphere in which the cup is placed;
Holding the substrate horizontally on the substrate holding portion;
Supplying the coating solution to the center of the substrate and rotating the substrate around the vertical axis via the substrate holding unit to spread the coating solution on the surface of the substrate;
Data corresponding to the opening amount corresponding to the number of rotations of the substrate is referred to a storage unit storing data corresponding to the opening amount of the opening and data corresponding to the exhaust amount for each number of rotations of the substrate, and Reading data corresponding to the displacement from a storage unit by a computer;
And a step of controlling the opening amount and the exhaust amount based on the read data. A storage medium for storing a computer program used in a coating apparatus for coating a rotating substrate with a coating liquid,
A storage medium, wherein the computer program includes a group of steps for carrying out the coating method according to claim 3 .

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