JP2003320299A - Thin film coating method and control unit thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin film coating method which coats a substrate by lowering the spray density of a chemical liquid due to a nozzle in the peripheral edge of the substrate to apply a thin film uniform in thickness to the entire surface of the substrate, and to provide a control unit thereof. <P>SOLUTION: In a method for coating the surface of the substrate 2 with the thin film by relatively moving a nozzle 1 for spraying the chemical liquid and the substrate 2, the spray density to the surface of the substrate 2 of the chemical liquid is made low in the peripheral edges 2a-2d of the substrate 2 as compared with the center of the substrate 2. By this constitution, the build-up of the thin film from the peripheral edge end 2a of the substrate 2 to the peripheral edge and part 2d thereof is suppressed, and the film thickness of the thin film can be made uniform over the entire surface of the substrate 2. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film coating method for spraying a thin film by spraying a liquid chemical on a substrate and a control apparatus therefor. The present invention relates to a thin film coating method and a control apparatus for the thin film coating method, which enables coating of a thin film having a uniform film thickness over the entire surface of a substrate.

[0002]

2. Description of the Related Art As a conventional thin film coating method, after dropping a desired amount of a chemical solution on a flat substrate surface, the substrate is rotated at a predetermined rotation speed and centrifugal force is used to spread the chemical solution on the entire surface of the substrate. While applying, the excess chemical was removed outside the substrate. There is also a method of spraying a chemical solution with a nozzle that moves two-dimensionally at a constant speed to apply a thin film on the substrate surface.

[0003]

However, in the conventional thin film coating method as described above, although there are differences in degree,
In either case, there is a problem that the film thickness becomes thick at the peripheral edge of the substrate due to the surface tension of the chemical solution. In the chemical spray method,
It is conceivable that the rebound of the chemical solution at the edge of the substrate increases the film thickness at the edge of the substrate.

As described above, the phenomenon that the film thickness becomes thick at the peripheral portion of the substrate is a problem in a liquid crystal display panel or the like in which it is necessary to form a fine electrode pattern in the peripheral portion of the substrate in order to secure the connection with the external drive circuit. Was becoming. That is, if the film thickness of the resist mask for forming the electrodes becomes thicker at the peripheral portion of the substrate, the adhesiveness between the exposure mask and the resist cannot be ensured, and it becomes difficult to form a resist mask with high accuracy. Therefore, when the electrodes are etched by using the resist mask as a mask, the electrodes are partially lost, or adjacent electrodes are short-circuited with each other.

In view of the above, the present invention addresses such a problem and applies a thin chemical solution to the peripheral edge of the substrate at a low spray density so that a thin film having a uniform thickness can be applied over the entire surface of the substrate. It is an object of the present invention to provide a thin film coating method and a control device for the thin film coating method.

[0006]

In order to achieve the above object, a thin film coating method according to the present invention is a method of coating a thin film on the surface of a substrate by moving a nozzle for spraying a chemical solution and a substrate relative to each other. The spray density of the chemical solution on the substrate surface is applied so that the spray density is lower in the peripheral portion than in the central portion of the substrate.

By such a method, the chemical liquid is sprayed relative to the substrate while spraying the chemical liquid by the nozzle so that the spray density of the chemical liquid on the substrate surface is lower in the peripheral portion of the substrate than in the central portion. As a result, the swelling due to the surface tension of the chemical liquid at the peripheral edge portion of the substrate is offset by lowering the spray density of the chemical liquid on the substrate surface and making the film thickness uniform.

Further, when the thin film is applied to the surface of the substrate, the distance between the nozzle and the surface of the substrate is set so that it is separated in the peripheral portion as compared with the central portion of the substrate. As a result, the distance between the nozzle and the substrate surface is increased in the peripheral portion compared to the central portion of the substrate, and the spray density of the chemical solution on the substrate surface is lowered.

As the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate, the distance between the nozzle and the surface of the substrate is gradually reduced, and the nozzle is provided above the substrate. When the distance between the substrate surface and the substrate surface reaches a predetermined value, the distance is maintained and moved by a predetermined distance, and as the nozzle approaches the other end of the peripheral edge of the substrate, The nozzles are retracted outside the substrate while gradually separating the nozzle intervals. As a result, the distance between the nozzle and the substrate surface is maintained at a predetermined value in the upper region of the substrate surface, and the distance is gradually increased outward from the peripheral portion of the substrate.

Further, the thin film is coated on the surface of the substrate by moving the nozzle at a peripheral portion of the substrate at a higher moving speed than at the central portion of the substrate. Thereby, the moving speed of the nozzle is increased in the peripheral portion of the substrate as compared with the central portion of the substrate, and the spray density of the chemical solution onto the substrate surface is lowered.

Then, as the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate, the moving speed of the nozzle is gradually decreased, and the moving speed of the nozzle in the upper region of the substrate surface. When the nozzle reaches a predetermined speed, the moving speed is maintained and moved by a predetermined distance, and the moving speed of the nozzle is gradually increased as the nozzle approaches the other end of the peripheral portion of the substrate. The nozzle is retracted to the outside of the substrate. As a result, the moving speed of the nozzle is maintained at a predetermined value in the upper region of the substrate surface, and gradually increased from the peripheral portion of the substrate outward.

Further, the thin film coating on the surface of the substrate is
While the nozzle reciprocally scans along the substrate surface,
The thin film is applied over the entire surface of the substrate by moving in a direction orthogonal to the scanning direction. As a result, the nozzle is reciprocally scanned along the surface of the substrate, and is further moved in the direction orthogonal to the scanning direction to apply a thin film over the entire surface of the substrate.

Further, the thin film coating control apparatus according to the present invention is
A nozzle that sprays a chemical liquid can be moved three-dimensionally.The size of the installed substrate and the moving distance of the nozzle from the moving distance of the nozzle to the edge of the substrate and the approach distance of the nozzle to the substrate surface are calculated. A control unit that issues a control command for controlling the approaching state of the nozzle to the substrate surface based on the calculation result, and a three-dimensional drive operation of the nozzle, and based on the control command of the calculation unit. As the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate, the distance between the nozzle and the substrate surface is gradually reduced, and the distance between the nozzle and the substrate surface in the upper region of the substrate. Reaches a predetermined value, the distance is maintained and moved by a predetermined distance, and as the nozzle approaches the other end of the peripheral portion of the substrate, the distance between the nozzle and the substrate surface is changed to the next value. A drive control unit for controlling so as to retract the nozzle outside the substrate while releasing the those equipped with.

With such a configuration, the size of the substrate and the moving distance of the nozzle set by the calculating unit are calculated from the moving distance of the nozzle to the substrate end and the approach distance of the nozzle to the substrate surface, and based on the calculation result. Issuing a control command to control the approaching state of the nozzle to the substrate surface, the drive control unit controls the three-dimensional drive operation of the nozzle, the nozzle based on the control command of the calculation unit, the nozzle of the substrate The distance between the nozzle and the surface of the substrate gradually becomes closer to the one end of the peripheral portion of the substrate from the outside, and the distance between the nozzle and the surface of the substrate reaches a predetermined value in the upper region of the substrate. Then, the substrate is moved by a predetermined distance while maintaining the distance, and as the nozzle approaches the other end of the peripheral portion of the substrate, the distance between the nozzle and the substrate surface is gradually increased and the substrate is gradually separated. Controls to retract the nozzle.

Further, the thin film coating control apparatus according to the present invention is
A nozzle that sprays a chemical liquid is two-dimensionally movable.The size of the installed substrate and the distance of movement of the nozzle to the edge of the substrate and the distance of the nozzle approaching the substrate surface are calculated. A control unit that issues a control command for controlling the approaching state of the nozzle to the substrate surface based on the calculation result, and a two-dimensional drive operation of the nozzle, and based on the control command of the calculation unit. As the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate, the moving speed of the nozzle is gradually decreased so that the moving speed of the nozzle reaches a predetermined speed in the upper region of the substrate surface. When it reaches, it is moved by a predetermined distance while maintaining its moving speed, and as the nozzle approaches the other end of the peripheral portion of the substrate, the moving speed of the nozzle is gradually increased to the outside of the substrate. Above nozzle A drive control unit for controlling so as to retract, in which with a.

With such a configuration, the size of the substrate and the moving distance of the nozzle installed by the calculating unit are calculated from the moving distance of the nozzle to the substrate end and the approach distance of the nozzle to the substrate surface, and based on the calculation result. A control command is issued to control the approaching state of the nozzle to the substrate surface, the two-dimensional driving operation of the nozzle is controlled by the control unit, and the nozzle is moved outside the substrate based on the control command of the calculation unit. When the moving speed of the nozzle gradually decreases toward one end of the peripheral edge of the substrate from one side, and the moving speed of the nozzle reaches a predetermined speed in the upper region of the substrate surface, the moving speed is changed. The nozzle is held and moved by a predetermined distance, and as the nozzle approaches the other end of the peripheral portion of the substrate, the moving speed of the nozzle is gradually increased to retract the nozzle out of the substrate. Control To.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a schematic perspective view showing an embodiment of a thin film coating method according to the present invention. In this thin film coating method, the nozzle 1 for spraying the chemical liquid and the substrate 2 are moved relative to each other so that the spray density of the chemical liquid is lower near the peripheral edge portions 2a to 2d than the central portion of the substrate 2. It was done like this.

First, as shown in FIG. 2, the nozzle 1 is sprayed with a chemical solution, and along the surface of the substrate 2, X in FIG.
Move in the direction. At this time, as the nozzle 1 approaches the end portion 2a of the substrate 2 from the outside of the substrate 2, the nozzle 1 descends so that the distance to the surface of the substrate 2 gradually approaches. Due to such an operation of the nozzle 1, the spray density of the chemical liquid in the vicinity of the end 2a of the substrate 2 gradually increases as the nozzle 1 approaches the substrate 2.

Then, when the distance between the nozzle 1 and the surface of the substrate 2 reaches z ₁ which is a predetermined value, the nozzle 1 stops descending, and while continuing the z ₁ value, the nozzle 1 continues to move in parallel along the surface of the substrate 2. . In this case, the spray density of the drug solution is constant.

Next, the nozzle 1 has a dimension x of the substrate 2 in the X direction.
After the parallel movement is performed by a distance substantially equal to ₁ , the distance gradually rises as the other end 2b of the substrate 2 is approached, and the distance from the surface of the substrate 2 is increased. Then, the substrate 2 is evacuated to the outside as it is, moved by a preset movement distance x ₂ and stopped. By such operation of the nozzle 1, the substrate 2
The spray density of the chemical solution in the vicinity of the end 2b of the
Becomes gradually lower as it is separated from the substrate 2.

Further, as shown in FIG.
When one scan in the direction is completed, the image is sent in the Y direction by a predetermined distance, and the scan in the opposite direction is performed in the X direction as described above. Then, while repeating this, the nozzle 1 moves in the Y direction to apply the thin film 3 over the entire surface of the substrate 2.

At this time, the nozzle 1 operates as shown in FIG. 3 for moving in the Y direction in FIG. That is, as the edge 2c of the substrate 2 is approached from the outside of the substrate 2, its height is lowered each time it is fed, and the distance between the nozzle 1 and the surface of the substrate 2 is shortened. At this time as well, the spray density of the chemical liquid gradually increases as the nozzle 1 approaches the end portion 2c of the substrate 2 as described above.

Then, the nozzle 1 is fed while maintaining a predetermined distance z ₁ value on the surface of the substrate 2. At this time, since the distance between the nozzle 1 and the substrate 2 is kept constant, the spray density of the chemical solution becomes constant.

Then, after moving a distance substantially equal to the y-direction dimension y ₁ of the substrate 2, as it approaches the other end 2d of the substrate 2, this time it rises every time it is fed, and the surface of the substrate 2 rises. Go away with. Then, it is retracted to the outside of the substrate 2 as it is, and moved by a preset movement distance y ₂ to Y.
Stop feeding in the direction. At this time as well, similar to the above,
As the nozzle 1 is separated from the end portion 2d of the substrate 2, the spray density of the chemical solution gradually decreases.

Thus, when the nozzle 1 approaches the peripheral edge portions 2a to 2d from the outside of the substrate 2 while spraying the chemical liquid, the nozzle 1 is operated so as to reduce the distance between the nozzle 1 and the surface of the substrate 2 When approaching the end portions 2a to 2d from the inside of the substrate and retracting to the outside of the substrate 2, the thin film is applied by operating the nozzle 1 and the surface of the substrate 2 at a distance. In the peripheral portion of the substrate 2, the spray density of the chemical liquid per unit area becomes low, and the increase in the film thickness at the peripheral edge portions 2a to 2d of the substrate 2 due to the surface tension of the chemical liquid and the rebound of the chemical liquid cancels out and becomes thicker A thin film having a constant film thickness can be applied also to the peripheral portion.

FIG. 4 is a block diagram showing an embodiment of a thin film coating control apparatus according to the present invention. The thin film coating control device 4 is used to carry out the above-described thin film coating method, and is configured to include an input unit 5, a calculation unit 6, and a drive control unit 7.

The input unit 5 is a unit for inputting various control data, and includes a board size input unit 8 and an X movement distance input unit 9.
And a Y movement distance input unit 10, a feed number input unit 11,
It has a Z value input unit 12. The board size input unit 8 calculates the X-direction dimension and the Y-direction dimension of the board by the X-movement distance input unit 9
Is the moving distance of the nozzle 1 in the X direction, the Y moving distance input unit 10 is the moving distance of the nozzle 1 in the Y direction, the feed number input unit 11 is the feed number of the Y direction, and the Z value input unit 12 Is a portion for inputting the height of the nozzle 1 on the surface of the substrate 2, and these are performed by operating a keyboard according to an instruction on a display screen (not shown).

Further, the calculation unit 6 calculates the size of the installed substrate 2 and the moving distance of the nozzle 1 from the moving distance of the nozzle 1 to the edge of the substrate and the approach distance of the nozzle 1 to the surface of the substrate 2, and the calculation result is obtained. Nozzle 1 for substrate 2 surface based on
Control command for controlling the approaching state of
It has an arithmetic unit 13, a Y arithmetic unit 14, and a Z arithmetic unit 15.

The X calculation unit 13 calculates and controls based on the input information of the board size input unit 8 and the X movement distance input unit 9 of the input unit 5 and the position information from the encoder 19 of the X-axis motor 16 described later. When the input data of the X movement distance input unit 9 and the movement distance of the nozzle 1 in the X direction based on the position information obtained from the encoder 19 match, the X axis motor 16 is stopped, and , When the Y-direction is fed once, the information is obtained from the Y calculation unit 14 and a control command for reversing the X-axis motor 16 is given by an X-described later.
The signal is sent to the drive control unit 22. Furthermore, X
The calculation unit 13 is based on the input information of the substrate size input unit 8 and the input information of the X movement distance input unit 9 from the X direction movement start point A of the nozzle 1 shown in FIG. The distance from the end 2b of the nozzle 2 to the X-direction movement end point B of the nozzle 1 is calculated, and based on the preset moving speed of the nozzle 1 in the X-direction, from the starting point A to the substrate end 2a or the substrate end 2b. The moving time of the nozzle 1 to the end point B is obtained, and this moving time information is transmitted to the Z calculation unit 15.

Further, the Y calculation unit 14 has a function of Y of the input unit 5.
Control information is obtained by calculating based on the input information of the moving distance input unit 10, the feed number input unit 11, the board size input unit 8 and the position information from the encoder 20 of the Y-axis motor 17, which will be described later. When the input data of the distance input unit 10 and the movement distance of the nozzle 1 in the Y direction based on the position information obtained from the encoder 20 match, the Y-axis motor 1
7, the feeding operation is stopped, and the feeding number input unit 11
Based on the input information of (1) and the information of the board size input section 8, a single feed width in the Y direction is calculated, and a control command thereof is issued to a Y drive control section 23 described later. Furthermore, the Y calculation unit 1
4 is based on the input information of the substrate size input unit 8 and the input information of the Y movement distance input unit 10 from the Y direction feed start position C of the nozzle 1 shown in FIG. 3 to the end 2c of the substrate 2 or the substrate 2 The distance from the end 2d of the nozzle 1 to the Y-direction feed end position D of the nozzle 1 is calculated, and based on the feed width, the number of feeds in the Y direction is calculated, and the feed count information is calculated. The information is transmitted to the Z calculator 15 described later.

Then, the Z calculation unit 15 detects the position information in the Z direction of the nozzle 1 obtained from the encoder 21 of the Z axis motor 18 described later, the information obtained from the X calculation unit 13 and the Y calculation unit 14, and the input unit 5 described above. Of the Z value input unit 12 to perform control to obtain control information.
The descending or ascending distance of the nozzle 1 in the Z direction is calculated from the input information, and the descending or ascending speed of the nozzle 1 in the Z direction is calculated based on the distance information and the moving time information obtained from the X calculator 13. The speed control command is calculated and the position information of the nozzle 1 from the encoder 21 and the Z value input unit 12 are calculated.
When the set value in 3 is matched, a control command to stop the Z-axis motor 18 is issued to the Z drive control unit 24 described later. Furthermore, the Z calculation unit 15 is connected to the Y calculation unit 14
A control for calculating the height from the surface of the nozzle 1 and the substrate 2 for each Y-direction feed based on the feed number information obtained from the above, and controlling the height of the nozzle 1 based on the position information of the encoder 21. A command is issued to the Z drive control unit 24 described later.

The drive control unit 7 controls the three-dimensional drive operation of the nozzle 1, and the nozzle 1 receives the substrate 2 from the outside of the substrate 2 based on a control command from the arithmetic unit 6. The nozzle 1 is made to approach the surface of the substrate 2 as it approaches one end of the peripheral edge of the substrate 2, and the nozzle 1 moves in parallel along the surface of the substrate 2 and approaches the other end of the substrate 2. Accordingly, the nozzle 1 is controlled so as to be separated from the surface of the substrate 2 so as to retract the nozzle 1 to the outside of the substrate 2, and an X-axis motor 16 for moving the nozzle 1 in the X direction. , Y-axis motor 1 to move in Y direction
7 and a Z-axis motor 18 for moving in the Z direction, and each of the motors 16-18 is provided with encoders 19, 20, 21 for measuring the moving distance.

A rotary encoder, a linear encoder, or the like can be applied to the encoders 19 to 21, and each motor 1
The position information of the nozzle 1 based on the driving of 6 to 18 is obtained by the encoders 19 to 21 and sent to the arithmetic unit 6. Further, the X drive control unit 22, the Y drive control unit 23, and the Z drive control unit 24 operate based on the control command from the calculation unit 6 to drive the respective motors 16 to 18 to make the nozzle 1 have a predetermined three-dimensional shape. I am trying to make it work.

Next, the operation of the thin film coating control apparatus 4 thus constructed will be described with reference to the flow charts of FIGS. 5 and 6. FIG. 5 shows the procedure of the movement operation of the nozzle 1 in the X direction. First, the substrate size in the X direction,
Control data such as X movement distance and Z value are input (step S1). Data input is performed by the board size input unit 8, the X movement distance input unit 9, and the Z value input unit 1 of the input unit 5 shown in FIG.
It is performed by the operation of 2. At this time, in the X calculation unit 13, the input substrate size x ₁ in the X direction and the nozzle 1 are input.
Is calculated based on the data of the moving distance x _{2 in} the X direction, and (x ₂ −x ₁ ) / 2, which is the distance from the moving start point A of the nozzle 1 to the end 2 a of the substrate 2 shown in FIG. To be
Further, the movement time from the movement start point A of the nozzle 1 to the substrate end portion 2a is calculated by the preset movement speed of the nozzle 1 in the X direction. Further, in the Z calculator 19, the input Z
The descending distance of the nozzle 1 (z ₂ −z ₁ ) is obtained from the value z ₁ and the height z ₂ of the movement start point A of the nozzle 1, and the distance from the movement start point A of the nozzle 1 to the substrate end 2a is obtained. The moving time information of is obtained from the X calculation unit 13, and the descending speed of the nozzle 1 is calculated and set. As a result, the nozzle 1 is placed in the standby state (step S2).

Next, a start switch (not shown) is turned on.
(Step S3). As a result, the injection of the chemical liquid from the nozzle 1 starts (step S4). At the same time, the forward rotation of the X-axis motor 16 is turned on (step S5), and the movement of the nozzle 1 in the X direction is started at a predetermined speed. Further, the normal rotation of the Z-axis motor 18 is also turned on (step S6), and the nozzle 1 descends at the set speed (step S7).

Then, in step S8, the Z calculator 15 determines whether or not the height Z of the nozzle 1 has reached the first input set value z ₁ based on the position information of the encoder 21. Here, in the case of “No” determination, step S
7, the nozzle 1 continues to descend until Z = z ₁ . When Z = z ₁ (Yes determination), the process proceeds to step S9, the Z calculation unit 15 issues a stop command to the Z drive control unit 24, and the Z axis motor 18 is turned off.

After that, the nozzle 1 maintains the height z ₁ and continues to move along the surface of the substrate 2 as shown in FIG.
And the moving distance in the X direction is (x ₁ + x ₂ ) /
2, that is, whether or not the edge 2b of the substrate 2 has been reached is determined by the X calculator 13 based on the position information of the encoder 19 (step S10). Here, in the case of the “No” determination, the movement of the nozzle 1 continues until the “Yes” determination is obtained.

If "Yes" is determined in step S10, the process proceeds to step S11, and the information is the Z calculation unit 1
5, the Z drive control unit 24 is further controlled, and the reverse rotation of the Z axis motor 18 is turned ON. Then, the nozzle 1 starts rising (step S12). Next, step S13
Then, the Z calculation unit 15 determines whether or not the nozzle 1 reaches the uppermost portion based on the position information of the encoder 21,
The nozzle 1 continues to rise until the “No” determination changes to the “Yes” determination. Here, when the determination is “Yes”, the Z calculation unit 15 issues a stop command to the Z drive control unit 24, and the Z axis motor 18 is turned off. At the same time, the encoder 19
The position of the nozzle 1 in the X direction based on the position information
It is determined by the calculation unit 13 that the above-mentioned position information is preset to X.
When the movement distance x _{2 in the} direction coincides, a stop command for the X-axis motor 16 is issued to the X-drive control unit 22 and the X-axis motor 16 is set to 0.
FF. Further, the chemical injection is also turned off (step S14).

By inputting a value smaller than x ₁ as the value of the substrate size in step S1, the X-direction position reaching the lowest point z ₁ of the nozzle 1 and the X-direction position at which the nozzle 1 starts to rise are entered. It can be located inside the ends 2a and 2b of the substrate 2. Therefore, it is not always necessary to input the actual substrate size as the input value of the substrate size, and it can be experimentally determined from the relationship with the coating film thickness at the edge of the substrate.

Next, the procedure of the movement operation of the nozzle 1 in the Y direction will be described with reference to FIG. First, in step S20, control data such as the substrate size in the Y direction, the Y movement distance, the number of feeds, and the Z value are input. Data is input by operating the board size input unit 8, the Y movement distance input unit 10, the feed number input unit 11, and the Z value input unit 12 of the input unit 5 shown in FIG. At this time, in the Y calculation unit 14,
Calculation is performed based on the input data of the substrate size y _{1 in} the Y direction and the movement distance y ₂ of the nozzle 1 in the Y direction, and the end portion 2 of the substrate 2 from the feed start position C of the nozzle 1 shown in FIG.
(y ₂ −y ₁ ) / 2, which is the distance to c, is obtained. Further, one feeding width is calculated from the moving distance y ₂ in the Y direction and the number of feedings, and based on this, how many feedings are performed from the feeding starting position C to the substrate end portion 2c. It is calculated (step S21). Further, in the Z calculation unit 15,
It is the descending distance of the nozzle 1 according to the input Z value z ₁ and the height z ₂ of the feed start position C of the nozzle 1 (z ₂ −z ₁ ).
Is obtained, the number of times of feeding from the feeding start position C of the nozzle 1 to the substrate end portion 2c is obtained from the Y calculation unit 14,
The height Z of the nozzle 1 with respect to the surface of the substrate 2 is calculated and set for each Y-direction feed. If this is expressed by a general formula, the number of feeds from the feed start position C to the substrate end 2c is n, and the height Z of the nozzle 1 for the i-th feed is: Becomes Here, n is a positive integer and i is 0 to n.

In step S22, the first application of the chemical liquid in the X direction is performed. At this time, the Y-axis motor 17 is off
The height of the nozzle 1 is calculated and set by the Z calculator 15 based on the equation (1). Specifically, since the feed in the Y direction is not performed, i = 0, and the height Z of the nozzle 1 is Z.
Is z2.

Next, the Y drive control unit 23 operates based on the control command from the Y calculation unit 14 to turn on the forward rotation of the Y-axis motor 17 (step S23), and the nozzle 1 for the first time in the Y direction is moved. It is sent (step S24). At this time, the Z calculation unit 15 obtains the information on the number of feeds in the Y direction from the Y calculation 14 and determines whether i = n based on the equation (1) (step S25). Here, in the case of “No” determination, the process returns to step S22, and the height of the nozzle 1 based on the equation (1) is set by obtaining the position information of the encoder 21 and controlling the Z drive control unit 24, and then continuing. The chemical solution is applied in the X direction. Then, steps S22 to S25 are repeated until i = n.

In step S25, "Yes" determination
If it becomes, the process proceeds to step S26 and the Y calculation unit 14
The Y drive control unit 23 is controlled based on the control command of
The motor 17 turns forward rotation and the nozzle 1 feeds once in the Y direction.
(Step S27). Here, the encoder 20
The nozzle 1 is fed by a predetermined feed width based on the position information.
Then, the Y operation unit 14 issues a stop command to the Y drive control unit 23.
The Y-axis motor 17 is turned off. On the other hand, nozzle 1
The height Z of the Z is based on the position information of the encoder 21.
The Z drive controller 24 is controlled by the calculator 15 to control the Z axis motor.
Drive 18 and z ₁Set to the value. In this state, in the X direction
The chemical solution is applied (step S28). And the
In step S29, the movement distance of the nozzle 1 in the Y direction is (y₁+
y₂) / 2 is the position information of the encoder 20
The Y calculation unit 14 makes a determination based on the above. That is, the nozzle 1
Is determined whether or not it has reached the end 2d of the substrate 2.
Here, in the case of “No” determination, the process returns to step S26.
, Steps S26 to S29 until a “Yes” determination is made.
Is repeated. Then, when the result is “Yes”, the step
Go to step S30.

In step S30, the Y-axis motor 17 is turned on.
The FF is performed, and the height Z of the nozzle 1 at each time of the feeding in the Y direction when the nozzle 1 is raised is performed in the same manner as in step S22.
Is calculated and set by the Z calculator 15 in FIG. When this is expressed by a general formula, the number of times of feeding from the substrate end 2d to the feeding end position D is n, and the height Z of the nozzle 1 for the i-th feeding is: Becomes Here, n is a positive integer and i is 0 to n.

Since i = 0 in step S30,
From the formula (2), the height Z of the nozzle 1 is z ₁And Z = z₁
The final chemical solution application in the X direction is performed. And
When the application of the chemical solution is completed, the Y-axis motor 17 rotates in the normal direction (
Step S31), and the nozzle 1 is sent (step S32).

Next, in step S33, the Z calculation unit 15 determines whether or not i = n based on the information on the number of feeds from the Y calculation unit 14. Here, in the case of the "No" determination, the process returns to step S30, and steps S30 to S33 are repeated until the "Yes" determination is made. Go up. When the determination is “Yes”, the Y-axis motor 17
Is turned off, the feeding operation of the nozzle 1 in the Y direction is completed (step S34), and the nozzle 1 reaches the uppermost portion (see FIG. 3).

As in the movement operation of the nozzle 1 in the X direction, by inputting a value smaller than y ₁ as the substrate size value in step S20, the lowest direction z ₁ of the nozzle 1 in the Y direction is reached. The position and the position in the Y direction at which the rising of the nozzle 1 is started can be a position inside the end portions 2c and 2d of the substrate 2. Therefore, it is not always necessary to input the actual substrate size as the input value of the substrate size, and it can be experimentally determined from the relationship with the coating film thickness at the edge of the substrate.

By combining the moving operation of the nozzle 1 in the X direction shown in FIG. 5 and the feeding operation in the Y direction shown in FIG. 6, it is possible to apply a uniform thin film over the entire surface of the substrate 2. Become.

In this way, the thin film coating control device 4 is
As shown in FIG. 1, the peripheral portion of the substrate is controlled so that the nozzle 1 and the surface of the substrate 2 are separated from each other so that the chemical liquid is sprayed. The spray density can be reduced, and the thin film can be applied by offsetting the increase in the film thickness at the peripheral edge portions 2a to 2d of the substrate 2 due to the surface tension of the chemical liquid. Therefore, it is possible to form a uniform thin film over the entire surface of the substrate.

As a device for causing the nozzle 1 to perform a three-dimensional operation, for example, an arm type robot shown in FIG. 7 or a device shown in FIG.
A three-dimensional drive device as shown in can be applied. The arm type robot shown in FIG. 7 performs a two-dimensional operation in the XY plane (a plane including the X axis and a plane perpendicular to the paper surface) by the rotational movement of the arms 25, 26, and 27, and the lifting shaft 28 moves the nozzle 1 in the Z direction. To move to. Arms 25, 26, 2
The nozzle 1 can be moved linearly by independently controlling the rotation angle and the rotation direction of 7.
Further, the moving speed of the nozzle 1 can also be controlled by controlling the rotation speeds of the arms 25, 26, 27.

Further, the three-dimensional drive device of FIG. 8 has a Y-axis drive section 30 which moves along a Y-axis direction guide shaft 29 arranged in parallel, and a Z which stands on the Y-axis drive section 30. A Z-axis drive unit 32 that moves along the axial guide shaft 31, a X-direction guide shaft 33 that connects the Z-axis drive unit 32 that is arranged facing each other, and an X that moves along the guide shaft 33. The X-axis drive unit 34 is provided with the nozzle 1.

The three-dimensional driving device shown in FIG. 8 has only the function of moving in the Z-axis direction, and moves the substrate (not shown) arranged facing the nozzle 1 in the X-direction and the Y-direction. You can also Alternatively, only the movement in the X direction may be performed on the substrate side.

Further, the method of applying the chemical solution so that the spray density of the chemical solution is lower in the vicinity of the peripheral edge than in the central part of the substrate is not limited to the above-mentioned method. In comparison, the coating may be applied faster at the peripheral portion. Specifically, the moving speed of the nozzle is gradually reduced as the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate, and the moving speed of the nozzle in the upper region of the substrate surface. When the nozzle reaches a predetermined speed, the moving speed is maintained and moved by a predetermined distance, and the moving speed of the nozzle is gradually increased as the nozzle approaches the other end of the peripheral portion of the substrate. The object of the present invention can also be achieved by retracting the nozzle outside the substrate. In this case, unlike the above-described embodiment, the nozzle and the substrate are held at a constant distance during the thin film coating period.

Further, the thin film coating control device used in the above thin film coating method is capable of moving the nozzle for spraying the chemical liquid two-dimensionally, and it is determined by the size of the installed substrate and the moving distance of the nozzle. An arithmetic unit for calculating a moving distance of the nozzle to the substrate end and an approaching distance of the nozzle to the substrate surface, and issuing a control command for controlling the approaching state of the nozzle to the substrate surface based on the arithmetic result; While controlling the two-dimensional driving operation, the moving speed of the nozzle is gradually increased as the nozzle approaches the one end of the peripheral portion of the substrate from the outside of the substrate based on the control command of the computing unit. When the moving speed of the nozzle reaches a predetermined speed in the upper region of the substrate surface, the moving speed is maintained and the nozzle is moved by a predetermined distance, and the nozzle moves to the other end of the peripheral edge of the substrate. Approaching With the can to gradually increase the moving speed of the nozzle is realized by configuration and a drive control unit for controlling so as to retract the nozzle outside the substrate.

[0055]

Since the present invention is constructed as described above,
According to the thin film coating method of the first aspect, the chemical liquid is sprayed relative to the substrate while spraying the chemical liquid with the nozzle so that the spray density of the chemical liquid on the substrate surface is lower in the peripheral portion of the substrate than in the central portion. To do. Thereby, the swelling due to the surface tension of the chemical liquid at the peripheral edge portion of the substrate can be offset by lowering the spray density of the chemical liquid on the substrate surface, and the film thickness can be made uniform. As a result, fine patterns can be formed on the peripheral portion of the substrate with good yield.

According to the second or third aspect of the invention, the spray density of the chemical solution on the substrate surface is lowered by separating the nozzle and the substrate surface at the peripheral edge portion compared to the central portion of the substrate. be able to. Therefore, it is possible to suppress the rise of the film thickness at the peripheral edge portion of the substrate and apply a thin film uniformly.

Further, according to the invention of claim 4 or 5, by increasing the moving speed of the nozzle at the peripheral portion of the substrate as compared with the central portion of the substrate, the spray density of the chemical liquid on the substrate surface can be lowered. it can. Therefore, also by this, it is possible to suppress the swelling of the film thickness at the peripheral edge portion of the substrate and apply the thin film uniformly.

Further, according to the invention of claim 6, the nozzle can be reciprocally scanned along the surface of the substrate and further moved in a direction orthogonal to the scanning direction. Therefore, a thin film can be applied over the entire surface of the substrate.

Further, according to the thin film coating control apparatus of the seventh aspect, the size of the substrate installed in the arithmetic unit, the moving distance of the nozzle from the moving distance of the nozzle to the end of the substrate, and the approach distance of the nozzle to the substrate surface can be calculated. The control unit controls the two-dimensional driving operation of the nozzle by a control command for controlling the approaching state of the nozzle to the substrate surface based on the calculation result and the control command of the calculation unit. Based on the above, as the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate, the moving speed of the nozzle is gradually decreased, and the moving speed of the nozzle is set to a predetermined value in the upper region of the substrate surface. When the speed is reached, the moving speed is maintained and moved by a predetermined distance, and the moving speed of the nozzle is gradually increased as the nozzle approaches the other end of the peripheral edge of the substrate. Outside above It can be controlled to retract the Le. Thereby, the swelling due to the surface tension of the chemical liquid at the peripheral edge portion of the substrate can be offset by lowering the spray density of the chemical liquid on the substrate surface, and the film thickness can be made uniform.

Further, according to the thin film coating control apparatus of the eighth aspect, the size of the substrate installed in the arithmetic unit, the moving distance of the nozzle from the moving distance of the nozzle to the end of the substrate, and the approach distance of the nozzle to the substrate surface are calculated. Then, a control command for controlling the approaching state of the nozzle to the substrate surface is issued based on the calculation result, and the control unit controls the two-dimensional driving operation of the nozzle, and based on the control command of the calculation unit. As the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate, the moving speed of the nozzle is gradually decreased, and the moving speed of the nozzle is a predetermined speed in the upper region of the substrate surface. When the nozzle reaches the other end of the peripheral edge of the substrate, the moving speed of the nozzle is gradually increased as the nozzle approaches the other end of the peripheral edge of the substrate. In the above noz It can be controlled to retract the. Also by this, the swelling due to the surface tension of the chemical liquid at the peripheral edge portion of the substrate can be offset by lowering the spray density of the chemical liquid on the substrate surface, and the film thickness can be made uniform.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a thin film coating method according to the present invention.

2 is a view taken along the line OO in FIG.

FIG. 3 is a view taken along the line P-P in FIG.

FIG. 4 is a block diagram showing a schematic configuration of a thin film coating control apparatus according to the present invention.

FIG. 5 is a flowchart illustrating a movement operation of the nozzle shown in FIG.

FIG. 6 is a flowchart illustrating a movement operation of the nozzle shown in FIG.

FIG. 7 is a schematic front view showing an example in which a nozzle is mounted on an arm type robot.

FIG. 8 is a schematic perspective view showing an example in which a nozzle is mounted on a three-dimensional driving device.

[Explanation of symbols]

1 ... Nozzle 2 ... Substrate 2a to 2d ... ends 4 ... Thin film coating controller 6 ... Calculation unit 7 ... Drive control unit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Keiichi Fujimori             1-10-7 East Gotanda, Shinagawa-ku, Tokyo A             IOS Gotanda Building Fujimori Institute of Technology Co., Ltd.             Inside the laboratory F term (reference) 2H025 AB17 EA04                 4D075 AA01 AA36 AA37 AA43 AA82                       AA85 CA47 DA06 DB13 DB14                       DC18 DC22 EA05 EA45                 4F035 AA03 BA22 BB06 BB32 BC02                 5F046 JA02 JA20

Claims (8)

[Claims] 1. A method of relatively moving a nozzle for spraying a chemical solution and a substrate to apply a thin film to the surface of the substrate, wherein the spray density of the chemical solution on the substrate surface is more peripheral than that of the central portion of the substrate. A thin film coating method, characterized in that the coating is performed so that it becomes lower in the area. 2. The coating method according to claim 1, wherein the thin film is applied to the surface of the substrate such that the distance between the nozzle and the surface of the substrate is greater in the peripheral portion than in the central portion of the substrate. Thin film coating method. 3. As the nozzle approaches the one end of the peripheral portion of the substrate from the outside of the substrate, the distance between the nozzle and the surface of the substrate is gradually reduced, and the nozzle is provided in an upper region of the substrate. When the distance between the substrate surface and the substrate surface reaches a predetermined value, the distance is maintained and moved by a predetermined distance, and as the nozzle approaches the other end of the peripheral portion of the substrate, The thin film coating method according to claim 2, wherein the nozzles are retracted to the outside of the substrate while gradually separating the nozzle intervals. 4. The thin film coating method according to claim 1, wherein the moving speed of the nozzle when coating the thin film on the surface of the substrate is faster at the peripheral portion than at the central portion of the substrate. Method. 5. The moving speed of the nozzle is gradually reduced as the nozzle approaches the one end portion of the peripheral portion of the substrate from the outside of the substrate, and the moving speed of the nozzle is increased in an area above the substrate surface. When it reaches a predetermined speed, the moving speed of the nozzle is maintained and moved by a predetermined distance, and the moving speed of the nozzle is gradually increased as the nozzle approaches the other end of the peripheral edge of the substrate. The thin film coating method according to claim 4, wherein the nozzle is retracted outside the substrate. 6. The thin film coating on the surface of the substrate is such that the nozzle reciprocally scans along the surface of the substrate and moves in a direction orthogonal to the scanning direction to form a thin film over the entire surface of the substrate. Coating is performed, The thin film coating method of any one of Claims 1-5 characterized by the above-mentioned. 7. A thin film coating control device capable of three-dimensionally moving a nozzle for spraying a chemical liquid, wherein the size of the installed substrate, the moving distance of the nozzle from the moving distance of the nozzle to the end of the substrate, and the substrate surface. A computing unit that computes the approach distance of the nozzle with respect to, and issues a control command to control the approaching state of the nozzle to the substrate surface based on the computation result, and controls the three-dimensional driving operation of the nozzle, and As the nozzle approaches the one end of the peripheral edge of the substrate from the outside of the substrate based on the control command of the arithmetic unit, the distance between the nozzle and the substrate surface is gradually made closer to the upper region of the substrate. When the distance between the nozzle and the substrate surface reaches a predetermined value, the distance is maintained and moved by a predetermined distance, and as the nozzle approaches the other end of the peripheral portion of the substrate, the substrate surface Thin coating control apparatus characterized by comprising a drive control unit for controlling so as to retract the nozzle to the substrate outside while releasing gradually the distance of the nozzle against. 8. A thin film coating control device capable of moving a nozzle for spraying a chemical liquid two-dimensionally, the size of a substrate on which it is installed, the distance of movement of the nozzle from the distance of movement of the nozzle to the edge of the substrate, and the surface of the substrate. A calculation unit that calculates the approach distance of the nozzle with respect to, and issues a control command that controls the approach state of the nozzle to the substrate surface based on the calculation result, and controls the two-dimensional drive operation of the nozzle, As the nozzle approaches the one end of the peripheral portion of the substrate from the outside of the substrate based on the control command of the arithmetic unit, the moving speed of the nozzle is gradually reduced, and the nozzle is provided in the upper region of the substrate surface. When the moving speed of reaches a predetermined speed, hold that moving speed and move it for a predetermined distance,
A drive control unit that controls the nozzle so that the nozzle moves out of the substrate by gradually increasing the moving speed of the nozzle as the nozzle approaches the other end of the peripheral edge of the substrate. A thin film coating control device characterized by the above.