JP2010062500A - Device and method for forming film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for forming a film capable of further preventing a variation of a film thickness between the center and the periphery of a substrate. <P>SOLUTION: In this device for forming a film, when a spray nozzle 6 sprays liquid to a glass substrate 4, a control part 9 moves the spray nozzle 6 while accelerating it from a circumferential part A to the center B of the glass substrate 4. When the spray nozzle 6 reaches the center B, the control part 9 moves the spray nozzle 6 at a uniform velocity in the center B of the glass substrate 4. From the center B to a circumferential part C, the control part 9 reduces the moving velocity of the spray nozzle 6 from the uniform velocity in the center B. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a film forming apparatus and a film forming method for forming a thin film by spraying a chemical solution onto a substrate.

  Conventionally, a film forming apparatus and a method for forming a thin film with a uniform film thickness on a substrate by spraying a chemical on the substrate have been disclosed.

  Patent Document 1 discloses a method of forming a thin film having a certain thickness by controlling the distance between a nozzle and a substrate. That is, in Patent Document 1, when the nozzle approaches the peripheral edge from the outside of the substrate, the distance between the nozzle and the surface of the substrate is reduced, and the nozzle approaches the peripheral edge from the inside of the substrate and retracts to the outside of the substrate. When going, it is operated to keep the distance away. Japanese Patent Application Laid-Open No. H10-228688 also discloses control for applying the nozzle so that the nozzle moving speed is higher at the peripheral portion than at the central portion of the substrate. As described above, Patent Document 1 describes a method of making the film thickness uniform by suppressing the bulge of the thin film at the peripheral edge of the substrate by increasing the distance between the substrate surface and the nozzle or by increasing the moving speed. ing.

  Patent Document 2 describes a manufacturing method for forming a uniform film thickness on a glass substrate by moving a spray gun at a predetermined speed.

Patent Document 3 describes a method of making the film thickness uniform by controlling the drive motor of the paint pump so that the coating film thickness becomes uniform according to the moving speed of the spray gun.
JP 2003-320299 A JP 2007-95362 A JP-A-1-41386

  Although the method disclosed in Patent Document 1 can suppress the bulge of the thin film at the peripheral edge of the substrate, further improvement in the variation in the thickness of the thin film other than the peripheral edge has been desired. In addition, the method disclosed in Patent Document 2 is desired to further improve the variation in the thickness of the thin film generated when the dryness of the chemical applied on the substrate is different between the end portion and the central portion of the substrate. It was. Furthermore, the method disclosed in Patent Document 3 may reduce the production efficiency when using an air spray that takes time to stabilize the discharge amount when the discharge amount is varied.

  In view of the above, an object of the present invention is to provide a film forming apparatus and a film forming method capable of further suppressing variations in film thickness between the central portion and the peripheral portion of a substrate.

In order to achieve the above object, the film forming apparatus of the present invention comprises:
In a film forming apparatus having a spray nozzle for injecting liquid onto a substrate and a moving means for moving at least one of the spray nozzle and the substrate in a predetermined direction, the spray nozzle moves when injecting liquid onto the substrate. The means moves at least one of the spray nozzle and the substrate so that the relative speed of the spray nozzle to the substrate is constant in the central portion of the substrate, which is a region not including the edge of the substrate, Including at least one of the spray nozzle and the substrate so that the spray nozzle accelerates relative to the substrate from the peripheral portion to the central portion of the substrate, which is an area adjacent to the central portion. From the central part to the peripheral part, move at least one of the spray nozzle and the substrate so that the spray nozzle decelerates relative to the substrate. It is characterized in.

  According to the present invention, it is possible to further suppress variations in film thickness between the central portion and the peripheral portion of the substrate.

  Embodiments of the present invention will be described below with reference to the drawings.

  Fig.1 (a) is a top view of the film-forming apparatus of this embodiment, FIG.1 (b) is an arrow line view of the DD line | wire direction shown to Fig.1 (a).

  The film forming apparatus is an apparatus for applying a resist to the glass substrate 4, and includes a substrate stage 5, a spray nozzle 6, and an XY orthogonal robot 10 in the chamber 1.

  In the film forming apparatus of this embodiment, film formation is performed in the chamber 1 so that the resist applied to the glass substrate 4 does not scatter outside the apparatus. A HEPA (High Efficiency Particulate Air) filter 2 is arranged at the upper part of the chamber 1 and an exhaust port 3 is provided at the lower part to form a laminar flow from the upper side of the chamber to the lower side so as not to disturb the air flow in the chamber 1. I am letting. This prevents dust from adhering to the glass substrate 4, prevents re-adhesion of the mist-like resist after spraying, or disturbs the flow of the sprayed resist so that the surface of the thin film becomes mottled or the film thickness becomes uneven. Is prevented. Furthermore, the ventilation by the laminar flow suppresses the concentration of the organic solvent in the chamber 1 below the explosion limit.

  The substrate stage 5 fixes the glass substrate 4 placed with the resist application surface facing upward by vacuum suction. Further, the substrate stage 5 can be rotated 90 degrees around the central axis perpendicular to the surface on which the glass substrate 4 is placed by the rotation driving unit 11. Since the substrate stage 5 is rotatable around the central axis O, the spray nozzle 6 can be scanned from both the vertical and horizontal directions of the glass substrate 4. Therefore, for example, when the scanning body of the spray nozzle 6 is limited because the structure is formed on the surface of the glass substrate 4, the scanning direction can be changed.

  The spray nozzle 6 sprays a chemical solution supplied from a chemical solution storage tank (not shown) onto the glass substrate 4 and is mounted on the XY orthogonal robot 10. The XY orthogonal robot 10 that is a nozzle moving means has an X-axis actuator 7 and two Y-axis actuators 8 extending in a direction orthogonal to the X-axis actuator 7, and is driven and controlled by the control unit 9. Each Y-axis actuator 8 is arranged on both outer sides of the substrate stage 5, and an X-axis actuator 7 is stretched over these two Y-axis actuators 8.

  The spray nozzle 6 is mounted on the X-axis actuator 7 and can reciprocate in the longitudinal direction of the X-axis actuator 7. The X-axis actuator 7 is mounted so as to be able to reciprocate in the longitudinal direction of the Y-axis actuator 8. Although FIG. 1 shows an example in which only one spray nozzle 6 is mounted on the X-axis actuator 7, a configuration having a plurality of spray nozzles 6 may be used in order to improve productivity.

  The film forming apparatus ejects a chemical solution from the spray nozzle 6 to form a thin film on the glass substrate 4, and the spray nozzle 6 moves while drawing the coating locus J shown in FIG. . The spray nozzle 6 is driven as follows to draw a coating locus J. The spray nozzle 6 is reciprocated in the longitudinal direction of the X-axis actuator 7, and the X-axis actuator 7 is moved by a predetermined pitch in the longitudinal direction of the Y-axis actuator 8, which is a direction intersecting the longitudinal direction of the X-axis actuator 7. This operation is repeated. As a result, the resist is applied while drawing the application locus J shown in FIG. At the time of substrate application, as will be described later, the spray nozzle 6 reciprocates in the longitudinal direction of the X-axis actuator 7 while being controlled for acceleration / deceleration or constant speed.

  The control unit 9 controls the operation of the XY orthogonal robot 10 and performs movement of the X-axis actuator 7 and the spray nozzle 6, particularly speed control.

  Here, speed control of the spray nozzle 6 by the control unit 9 will be described with reference to FIGS.

  FIG. 2 is a graph showing the relationship between the moving distance of the spray nozzle 6 and the scanning speed of the spray nozzle 6. FIG. 3 is a graph showing the relationship between the X direction of the glass substrate 4 (see FIG. 1) and the film thickness of the thin film formed on the glass substrate 4. In addition, the center part B shown in FIG. 3 refers to the area | region which does not include the edge part 4b of the glass substrate 4, and the peripheral parts A and C refer to the area | region which adjoins the center part B and includes the edge part 4b. To do.

  When a large glass substrate is scanned with a spray nozzle at a constant speed to apply a resist, the resist deposition efficiency varies due to the difference in the dryness of the resist between the peripheral portion and the central portion. As a result, as shown in FIG. 3, it is known that the peripheral portions A and C are thinner by about 20% than the film thickness T1 of the central portion B (t3 in FIG. 3).

  Therefore, the control unit 9 of the present embodiment performs control as shown in the graph of FIG. Hereinafter, this control by the control unit 9 will be described. In addition, the spray nozzle 6 shall move from the left side in FIG. 2 to the right side. Moreover, the scanning area | region of the spray nozzle 6 shall start from the outer side of the edge part 4b of the glass substrate 4, and shall stop at the position which came out on the outer side from the edge part 4b, after passing on the glass substrate 4. FIG.

  The control unit 9 outputs a signal to the X-axis actuator 7 so as to start driving the spray nozzle 6 in a stopped state outside the end 4 b of the glass substrate 4. As a result, the X-axis actuator 7 starts scanning the spray nozzle 6.

  In the peripheral portion A (acceleration region), the control unit 9 outputs a signal to the X-axis actuator 7 so as to accelerate the spray nozzle 6 to a predetermined speed. That is, the spray nozzle 6 is scanned so that the spray nozzle 6 is relatively accelerated with respect to the glass substrate 4, and is accelerated to a predetermined speed. The predetermined speed is a speed at which the spray nozzle 6 is scanned in the central portion B.

  When the spray nozzle 6 passes through the peripheral portion A while accelerating and reaches the central portion B, the constant velocity control of the spray nozzle 6 is started. That is, the control unit 9 outputs a signal for stopping acceleration control to the X-axis actuator 7 and outputs a signal so that the spray nozzle 6 is driven and scanned at a constant speed. Thereby, in the center part B (constant speed area | region), the spray nozzle 6 is scanned so that the relative speed with respect to the glass substrate 4 may become fixed.

  When the spray nozzle 6 is scanned at a constant speed, passes through the central part B, and reaches the peripheral part C, deceleration control of the spray nozzle 6 is started. In other words, the control unit 9 outputs a signal for stopping the constant velocity control to the X-axis actuator 7 and outputs a signal so as to drive and scan the spray nozzle 6 while decelerating. Thereby, in the peripheral part C (deceleration area | region), the spray nozzle 6 is scanned, decelerating relatively with respect to the glass substrate 4. FIG.

  When the spray nozzle 6 moves outside the peripheral portion C (deceleration region), the control unit 9 outputs a signal to the X-axis actuator 7 so as to stop driving. Thereby, the spray nozzle 6 stops. Thus, the forward scanning of the reciprocating scanning of the spray nozzle 6 by the X-axis actuator 7 is completed.

  After the spray nozzle 6 stops, the control unit 9 outputs a signal to the Y-axis actuator 8 so as to move the X-axis actuator 7 by a predetermined amount in the longitudinal direction of the Y-axis actuator 8.

  After the X-axis actuator 7 has moved by a predetermined amount, the spray scan of the spray nozzle 6 by the X-axis actuator 7 is performed. The control in this case is the same as the forward scanning described above except that the peripheral portion C is an acceleration region and the peripheral portion A is a deceleration region, and detailed description thereof is omitted.

  As described above, in the film forming apparatus of the present embodiment, the moving speed of the spray nozzle 6 is slower in the acceleration region and the deceleration region than in the constant velocity region. As a result, the resist coating amount at the peripheral portions A and C is larger than the resist coating amount at the central portion B. For this reason, the uniformity of the film thickness after drying the resist is improved from the state of t3 in FIG. 3 to t2.

  Also in the Y direction, in order to increase the coating amount of the peripheral portions A and C, the uniformity of the film thickness can be obtained by setting the speed of the constant velocity region to be slow for several lines from the start of scanning and several lines before the end of scanning improves.

  As described above, according to the present embodiment, the spray nozzle 6 is accelerated and decelerated in the peripheral portions A and C, and the resist spray is performed while moving at a constant speed in the central portion B, whereby a uniform film is formed on the glass substrate 4. A thick thin film can be formed.

  In the above description, the method of moving the spray nozzle 6 with respect to the glass substrate 4 at an acceleration / deceleration or at an equal speed has been described. However, the present invention is not limited to this. That is, the film forming apparatus according to the present embodiment may have a stage moving unit that moves the substrate stage 5 and moves the substrate stage 5. In this case, the control unit 9 controls the moving speed at which the stage moving unit moves the substrate stage to move the substrate stage 5 relative to the spray nozzle 6. That is, when the spray nozzle 6 is at a position corresponding to the peripheral portion A, the substrate stage 5 is moved while being accelerated. The control unit 9 moves the substrate stage 5 at a constant speed when the spray nozzle 6 is at a position corresponding to the central portion B, and moves the substrate stage when the spray nozzle 6 is at a position corresponding to the peripheral portion C. The stage 5 is moved while decelerating. In the present invention, both the spray nozzle 6 and the substrate stage 5 may be relatively moved to perform similar control.

  Examples of the present invention will be described below.

  In this example, a film was formed by applying a resist to a glass substrate 4 for FPD having a size of 1300 mm × 800 mm using the film forming apparatus shown in FIG.

  As the spray nozzle 6, a two-fluid spray was used, and the resist was atomized and applied to the substrate surface.

The scanning distance in the X direction was 1300 mm, the distance in the X direction of the peripheral part A was about 250 mm, the central part B was about 800 mm, and the peripheral part C was about 250 mm. In the control unit 9, the acceleration and deceleration at the peripheral parts A and C were set to 320 mm / s ² , and the scanning speed at the central part B was set to 400 mm / sec. Then, each time one line scan was performed, the resist was applied to the entire surface of the substrate by scanning the nozzles 6 alternately left and right while moving the pitch.

  After coating, the resist film thickness was about 2000 nm at the position t3 in FIG. 3 and about 2250 nm at the position T1. This measurement result is obtained by measuring the film thickness from a position of 20 mm from the end of the substrate because the uniformity of the thin film is about 20 mm from the end of the substrate.

  As described above, it was confirmed that the uniformity of the film thickness of the substrate was improved.

It is the top view and DD line arrow figure of the film-forming apparatus of this invention. It is a graph which shows the relationship between the movement distance of a spray nozzle, and the scanning speed of a spray nozzle. It is a graph which shows the relationship between the X direction of a glass substrate, and the film thickness of the thin film formed on the glass substrate.

Explanation of symbols

4 Glass substrate 6 Spray nozzle 7 X-axis actuator 8 Y-axis actuator 9 Control unit 10 XY orthogonal robot A, C Peripheral part B Central part

Claims (6)

In a film forming apparatus comprising: a spray nozzle that ejects liquid onto a substrate; and a moving unit that moves at least one of the spray nozzle and the substrate in a predetermined direction.
When the spray nozzle ejects liquid onto the substrate, the moving means is
In the central portion of the substrate, which is a region not including the end portion of the substrate, at least one of the spray nozzle and the substrate is moved so that the relative speed of the spray nozzle with respect to the substrate is constant,
From the peripheral part of the substrate, which is an area including the end part and adjacent to the central part, to the central part, the spray nozzle and the spray nozzle are accelerated so that the spray nozzle is relatively accelerated with respect to the substrate. Move at least one of the substrates,
From the central part to the peripheral part, at least one of the spray nozzle and the substrate is moved so that the spray nozzle is relatively decelerated with respect to the substrate. .   The moving means includes nozzle moving means for moving the spray nozzle in a predetermined direction, stage moving means for moving a substrate stage on which the substrate is placed, speed control of the nozzle moving means and the stage moving means. The film-forming apparatus of Claim 1 which has a control part to perform.   The film forming apparatus according to claim 1, wherein the moving unit moves at least one of the spray nozzle and the substrate at a predetermined pitch in a direction intersecting the predetermined direction.   4. The apparatus according to claim 2, further comprising a chamber covering at least the spray nozzle, the nozzle moving means, and the substrate stage, wherein a filter is disposed at an upper portion of the chamber, and an exhaust port is formed at a lower portion of the chamber. 2. The film forming apparatus according to 1.   5. The film forming apparatus according to claim 2, further comprising a rotation driving unit configured to rotate the substrate stage about a central axis perpendicular to a surface on which the substrate is placed. In the film forming method of forming a thin film on the substrate by ejecting liquid from the spray nozzle while moving at least one of the spray nozzle and the substrate,
In the central portion of the substrate, which is a region not including the end portion of the substrate, at least one of the spray nozzle and the substrate is moved so that the relative speed of the spray nozzle with respect to the substrate is constant,
From the peripheral part of the substrate, which is an area including the end part and adjacent to the central part, to the central part, the spray nozzle and the spray nozzle are accelerated so that the spray nozzle is relatively accelerated with respect to the substrate. Move at least one of the substrates,
From the central portion to the peripheral portion, at least one of the spray nozzle and the substrate is moved so that the spray nozzle is relatively decelerated with respect to the substrate. .

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