JP2007098326A - Coating film forming apparatus and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating film forming apparatus in which the distance between a slit like discharge port formed on a nozzle and a substrate to be treated is controlled to a prescribed interval regardless of the change of ambient temperature environment in the case of forming the film by discharging a treating liquid from the discharge port to the substrate, and to provide its control method. <P>SOLUTION: The coating film forming apparatus is provided with first and second ball screw shafts 61, 71 respectively erected on the left and light sides of a placing base 50 in the vertical direction, first and second elevating members 62, 72 each provided to vertically move along the ball screw shaft by the rotation of the first and second ball screw shafts 61, 71 around the vertical axis and supporting a nozzle 51 from both left and light sides, first and second distance detecting means 68, 78 provided in the nozzle 51 and respectively detecting the distance between one end side of the slit like discharge port 51a and the substrate G to be treated, and another end side and the substrate G and a control means 80 for controlling the rotation of the first and second ball screw shaft 61, 71. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coating film forming apparatus capable of correcting the position of a nozzle having a slit-like discharge port and a control method therefor.

  For example, in LCD manufacturing, a predetermined film is formed on an LCD substrate, which is a substrate to be processed, and then a photoresist film is applied to form a resist film, and the resist film is exposed in accordance with a circuit pattern. A circuit pattern is formed by a so-called photolithography technique of developing the film. In this photolithography technology, the LCD substrate, which is the substrate to be processed, undergoes a series of processes such as cleaning processing → dehydration baking → adhesion (hydrophobization) processing → resist coating → prebaking → exposure → development → post baking. A predetermined circuit pattern is formed on the resist layer.

  Conventionally, in such processing, processing units for performing each processing are arranged on both sides of the transport path in consideration of the process flow, and a substrate to be processed is carried into each processing unit by a central transport apparatus that can travel on the transport path. This is performed by a processing system in which one or a plurality of process blocks to be output are arranged. Since such a processing system is basically random access, the degree of freedom of processing is extremely high.

In such a processing system, as a method for forming a resist film by applying a resist solution to an LCD substrate, there is a method using a resist supply nozzle having slit-like discharge ports as shown in FIG.
In this method, the mounting table 201 on which the LCD substrate G is mounted and the resist supply nozzle 200 that applies the resist solution R to the substrate G in a strip shape are relatively moved in a direction perpendicular to the longitudinal direction of the nozzle 200. The coating process is performed. In this case, the resist supply nozzle 200 has a nozzle discharge port 200a in which a minute gap (slit) extending in the width direction of the substrate G is formed, and a resist solution discharged in a strip shape from the slit-shaped discharge port 200a. By supplying R to the entire surface of the substrate G, a resist film is formed.

  According to this method, since the resist solution R is discharged (supplied) from one side of the substrate G to the other side in a strip shape, the resist solution R is not wasted and averaged over the entire surface of the square substrate G. A resist film can be formed. Such a coating film forming method is disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 10-156255).

By the way, in the coating process using the nozzle having the slit-shaped discharge port as shown in FIG. 6, when performing the coating process on the substrate, the distance between the discharge port and the upper surface of the substrate is very short (for example, 50 μm).
For this reason, a mechanism capable of controlling the lift position with high accuracy is required as the nozzle lifting means for controlling the nozzle to descend from the standby position to the discharge position, and the rigidity can be maintained as having such a mechanism. And a ball screw mechanism having a high load bearing capacity is used.

  Here, FIG. 7 schematically shows a configuration example of a ball screw mechanism for moving the nozzle 200 up and down. A ball screw mechanism 210 provided on each of the left and right sides of the nozzle 200 has a ball screw shaft 210a having a spiral ball screw groove formed on the outer periphery and a nut structure that is screwed to the shaft 210a. The elevating member 210b can be moved up and down along with the motor 210c. The motor 210c rotates the ball screw shaft 210a around the vertical axis. The rotary encoder 210d detects the number of rotations of the motor 210c.

The left and right sides of the nozzle 200 are supported by an elevating member 210b, and the nozzle 200 moves up and down in conjunction with the elevating operation of the elevating member 210b. The motor 210c is driven and controlled by a control means (not shown), and the output from the rotary encoder 211 is converted into a distance dimension to control the up and down movement of the nozzle 200.
JP-A-10-156255

However, in the nozzle lifting / lowering means having the ball screw mechanism 210 as described above, the temperature of the ball screw shaft 210a gradually changes due to the heat radiation of the motor 210c and the change in ambient temperature accompanying the lifting / lowering operation of the nozzle, and the shaft expands Or there was a problem of shrinking. That is, when the shaft expands or contracts, the shaft length changes, and the position of the nozzle 200 cannot be set according to the processing recipe in which the distance between the discharge port 200a and the mounting table 201 is defined. It was.
In addition, the lengths of the two ball screw shafts 210a provided on the left and right sides of the nozzle 200 may be different. In this case, the distance between the slit-like discharge port 200a and the upper surface of the substrate G is one end side of the discharge port. There was a problem that the film thickness was different from the other end side.

Specifically, for example, if the temperature of the ball screw shaft changes from 20 ° C. to 25 ° C., the ball screw shaft made of iron material and having a length of 500 mm expands 11.8 × 10 ⁻⁶ times per 1 ° C. Therefore, the amount of change Δd of the distance d between the discharge port 200a and the upper surface of the substrate G is expressed by the following equation (1).

本来設定すべき所定の距離寸法ｄが５０μｍであるとすれば、この変化量は塗布処理に大きく影響することは明らかである。

If the predetermined distance dimension d to be originally set is 50 μm, it is clear that this amount of change greatly affects the coating process.

  Further, in order to verify this phenomenon, the applicant of the present application measured the temperature change of the ball screw shaft and the discharge position of the nozzle (distance between the discharge port and the upper surface of the substrate) and examined the relationship between them. The measurement results are shown in the graph of FIG. In this graph, the horizontal axis represents the number of times the nozzle is moved up and down per unit time, and the vertical axis represents the temperature of the ball screw shaft and the nozzle discharge position deviation amount (deviation amount with respect to a predetermined discharge position). As shown in this graph, it was confirmed that the discharge position of the nozzle fluctuated in proportion to the temperature change of the ball screw shaft.

  The present invention has been made under the circumstances as described above. When forming a film by discharging a processing liquid onto a substrate to be processed from a slit-like discharge port formed in a nozzle, the discharge port and the target are processed. An object of the present invention is to provide a coating film forming apparatus and a control method therefor that can set the distance to the substrate at a predetermined interval regardless of changes in the ambient temperature environment.

  In order to solve the above-described problems, a coating film forming apparatus according to the present invention includes a mounting table that holds a substrate to be processed in a horizontal posture and a slit-like discharge port that extends in the width direction of the substrate to be processed. In a coating film forming apparatus that includes a nozzle and applies a processing liquid to the substrate to be processed from a discharge port of the nozzle in a strip shape, the first and the second standing vertically on the left and right sides of the mounting table, respectively A first ball screw shaft and a first ball screw shaft that is provided to be movable up and down along the ball screw shaft by rotating around the vertical axis of the first and second ball screw shafts, and supports the nozzle from both the left and right sides. And a second elevating member, and first and second distance detecting means that are provided in the nozzle and detect distance dimensions from one end side and the other end side of the slit-like discharge port to the substrate to be processed, respectively. The first and second balls Control means for controlling the rotation of the same shaft, and the control means controls the rotation of the first and second ball screw shafts based on the detection results of the first and second distance detection means, respectively. And correcting the position of the nozzle with respect to the substrate to be processed.

  According to such a configuration, it is possible to detect whether there is a difference in distance from the substrate to be processed on both the left and right sides of the nozzle, and it is possible to perform position correction based on the detection result. Therefore, the treatment liquid can be applied so that the distance between the slit-like ejection port and the substrate to be processed is a predetermined distance and a desired film thickness.

  A first casing that houses the first ball screw shaft and the first lifting member; a second casing that houses the second ball screw shaft and the second lifting member; A first linear scale mechanism that is provided outside the casing and measures the moving distance on one end side of the nozzle, and a first linear scale mechanism that is provided outside the second casing and measures the moving distance on the other end side of the nozzle. Two linear scale mechanisms, and the control means controls the rotation of the first and second ball screw shafts based on the length measurement results of the first and second linear scale mechanisms, respectively. It is desirable to move the nozzle down from the nozzle standby position to the application execution position and perform position correction on the substrate to be processed.

  By separating the ball screw shaft and the linear scale mechanism by the casing in this way, the linear scale mechanism is not affected by the ambient temperature on the ball screw shaft side and does not expand or contract due to a temperature change. Therefore, the nozzle can be lowered to the application execution position by accurate measurement.

  A first motor that rotationally drives the first ball screw shaft; a second motor that rotationally drives the second ball screw shaft; and a first motor that detects the rotational speed of the first motor. A rotary encoder; a second rotary encoder that detects the number of rotations of the second motor; a first standby position detection means that detects a state where one end of the nozzle is positioned at a nozzle standby position; Second standby position detecting means for detecting a state where the end side is located at the nozzle standby position, and the control means is configured to return the first and second rotary encoders when returning the nozzle from the application execution position to the standby position. The nozzle is raised to a position where the counter output value of the nozzle reaches an initial value, and further, the nozzle is moved to a position where the first and second standby position means detect the nozzle, It is desirable to identify the aircraft position.

  When the nozzle is returned to the standby position after the processing liquid is applied to the substrate to be processed, the length of the ball screw shaft may have changed. Returning to the standby position using the linear scale mechanism based on the distance is not accurate. Therefore, as described above, the nozzle is returned to the accurate standby position by using the rotary encoder capable of specifying the position close to the nozzle standby position by the counter value and the standby position detection sensor capable of specifying the accurate standby position. Can do.

Moreover, it is desirable to provide a temperature adjusting means for controlling the temperature in the first and second casings.
By providing the temperature adjusting means in this way, the temperature change of the ball screw shaft can be suppressed, and the amount of expansion and contraction of the shaft can be reduced.

  In order to solve the above-described problems, a control method for a coating film forming apparatus according to the present invention includes a mounting table that holds a substrate to be processed in a horizontal posture, and a vertical position on each of the left and right sides of the mounting table. First and second ball screw shafts provided, and first and second elevating members that move up and down along the ball screw shafts by rotating around the vertical axes of the first and second ball screw shafts. A nozzle that is supported by the first and second elevating members from both left and right sides and has a slit-like discharge port extending in the width direction of the substrate to be processed; and a nozzle provided in the nozzle from the discharge port. A control method for a coating film forming apparatus, comprising first and second distance detecting means for detecting a distance dimension to a processing substrate, and applying a processing liquid in a strip shape from the nozzle outlet to the substrate to be processed. The first and second distance detection Means for detecting the distance dimensions between the one end side and the other end side of the slit-like discharge port and the substrate to be processed, and based on the detection results of the first and second distance detection means, The first and second ball screw shafts are each controlled in rotation, and the step of correcting the position of the nozzle with respect to the substrate to be processed is executed.

  In this way, it is possible to detect whether there is a difference in distance from the substrate to be processed on both the left and right sides of the nozzle, and it is possible to perform position correction based on the detection result. Therefore, the treatment liquid can be applied so that the distance between the slit-like ejection port and the substrate to be processed is a predetermined distance and a desired film thickness.

In addition, the coating film forming apparatus includes first and second linear scale mechanisms that measure the moving distances of the one end side and the other end side of the nozzle, respectively, and are detected by the first and second distance detecting means. Based on the result, in the step of correcting the position of the nozzle with respect to the substrate to be processed, rotation control of the first and second ball screw shafts is performed based on the length measurement results by the first and second linear scale mechanisms, respectively. Preferably, the nozzle is moved downward from the nozzle standby position to the application execution position.
In this way, the moving distance of the nozzle can be measured by the linear scale mechanism that is not affected by the expansion and contraction of the ball screw shaft, and the nozzle can be accurately lowered to the application execution position.

  The coating film forming apparatus includes: a first motor that rotationally drives the first ball screw shaft; a second motor that rotationally drives the second ball screw shaft; and the rotation of the first motor. A first rotary encoder that detects the number, a second rotary encoder that detects the rotation speed of the second motor, and a first standby position detection sensor that detects a state where one end of the nozzle is positioned at the standby position And a second standby position detection sensor that detects a state in which the other end side of the nozzle is positioned at the standby position, and after applying the coating process to the substrate to be processed, returning the nozzle from the application execution position to the standby position. The first and second rotary encoders raise the nozzle to a position where the counter output values become initial values, and the first and second standby position detecting means are Perform the step of moving said nozzle to a position for detecting the Le, it is desirable to identify nozzle standby position.

  As described above, the nozzle can be returned to the accurate standby position by using the rotary encoder capable of specifying the position near the standby position of the nozzle by the counter value and the standby position detecting means capable of specifying the accurate standby position. .

  According to the present invention, when forming a film by discharging the processing liquid onto the substrate to be processed from the slit-shaped discharge port formed in the nozzle, the distance between the discharge port and the substrate to be processed is changed to the ambient temperature environment. Regardless of this, it is possible to obtain a coating film forming apparatus and a control method therefor that can be set at a predetermined interval.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing the overall configuration of a resist coating and developing treatment apparatus including a resist coating apparatus as a coating film forming apparatus according to the present invention. First, the resist coating and developing apparatus 100 will be described.
The resist coating and developing processing apparatus 100 includes a cassette station 1 on which a plurality of cassettes C that accommodate a plurality of LCD substrates G (hereinafter referred to as substrates G) that are substrates to be processed are placed, and a resist that is a processing liquid on the substrate G. A processing station 2 having a plurality of processing units for performing a series of processing including liquid application and development, and an interface station 3 for transferring the substrate G to and from the exposure apparatus 4 are provided. .
The cassette station 1 and the interface station 3 are arranged at both ends of the processing station 2, respectively. In FIG. 1, the longitudinal direction of the resist coating and developing apparatus 100 is defined as the X direction, and the direction perpendicular to the X direction on the plane is defined as the Y direction.

  The cassette station 1 includes a transfer device 11 for carrying in and out the substrate G between the cassette C and the processing station 2. This transfer device 11 has a transfer arm 11a, and can move on a transfer path 10 provided along the Y direction which is the arrangement direction of the cassettes C. Between the cassette C and the processing station 2 by the transfer arm 11a. Then, the substrate G is carried in and out.

The processing station 2 has two parallel rows of transfer lines A and B for transferring the substrate G extending in the X direction, and scrub cleaning is performed from the cassette station 1 side to the interface station 3 along the transfer line A. A part of the processing unit (SCR) 21, the first heat treatment unit section 26, the resist coating processing unit 23, and the second heat treatment unit section 27 are arranged.
An excimer UV irradiation unit (e-UV) 22 is provided on a part of the scrub cleaning unit (SCR) 21.

  Further, a part of the second heat treatment unit section 27, the development processing unit (DEV) 24, and the i-line UV irradiation unit (i-UV) 25 from the interface station 3 side toward the cassette station 1 along the transfer line B. And the 3rd heat processing unit 28 is arranged.

  In the processing station 2, the processing units and the transfer devices are arranged so as to constitute the two rows of transfer lines A and B and basically in the order of processing. A space 40 is provided between them. And the shuttle 41 is provided so that this space part 40 can be reciprocated. The shuttle 41 is configured to hold the substrate G, and the substrate G can be transferred to and from the transfer lines A and B.

  In addition, the interface station 3 has a transfer device 42 for loading and unloading the substrate G between the processing station 2 and the exposure device 4, a buffer stage (BUF) 43 for arranging a buffer cassette, and a cooling function. An extension / cooling stage (EXT / COL) 44, which is a substrate transfer section, is provided, and an external apparatus block 45 in which a tiger (TITLER) and a peripheral exposure apparatus (EE) are vertically stacked is a transport apparatus 42. It is provided adjacent to. The transfer device 42 includes a transfer arm 42a, and the transfer arm 42a carries in and out the substrate G between the processing station 2 and the exposure device 4.

In the resist coating and developing apparatus 100 configured in this way, first, after the substrate G in the cassette C arranged in the cassette station 1 is carried into the processing station 2 by the transport apparatus 11, first, the excimer UV irradiation unit. A scrub pretreatment by (e-UV) 22 and a scrub cleaning treatment by a scrub cleaning unit (SCR) 21 are performed.
Next, the substrate G is carried into the heat treatment unit blocks (TB) 31 and 32 belonging to the first heat treatment unit section 26, and a series of heat treatments (dehydration baking treatment, hydrophobic treatment, etc.) are performed. The substrate is transferred in the first heat treatment unit section 26 by the transfer device 33.

Thereafter, the substrate G is carried into the resist coating processing unit 23 and subjected to a resist liquid film forming process. In this resist coating processing unit 23, first, a resist solution is applied to the substrate G in a resist coating apparatus (CT) 23a, and then a vacuum drying process is performed in a vacuum drying unit (VD) 23b.
The resist coating apparatus (CT) 23a included in the resist coating processing unit 23 is applied as a coating film forming apparatus according to the present invention, and will be described later in detail.
After the resist film forming process in the resist coating unit 23, the substrate G is carried into the heat treatment unit blocks (TB) 34 and 35 belonging to the second heat treatment unit section 27, and a series of heat treatments (such as pre-bake treatment) are performed. Is called. The substrate is transferred in the second heat treatment unit section 27 by the transfer device 36.

  Next, the substrate G is transferred to the extension / cooling stage (EXT / COL) 44 of the interface station 3 by the transfer device 36, and is transferred to the peripheral exposure device (EE) of the external device block 45 by the transfer device 42. Therefore, the substrate G is exposed to remove the peripheral resist, and is then transported to the exposure device 4 by the transport device 42, and the resist film on the substrate G is exposed to form a predetermined pattern. In some cases, the substrate G is accommodated in a buffer cassette on the buffer stage (BUF) 43 and then transferred to the exposure apparatus 4.

  After the exposure is completed, the substrate G is transported to the upper TITER of the external device block 45 by the transport device 42 of the interface station 3, and predetermined information is written on the substrate G. Thereafter, the substrate G is placed on an extension / cooling stage (EXT / COL) 44, and then transferred to the processing station 2 again. For example, the substrate G is transported to the development processing unit (DEV) 24 by a roller transport mechanism, where development processing is performed.

After completion of the development processing, the substrate G is carried from the development processing unit (DEV) 24 to the i-ray UV irradiation unit (i-UV) 25, and the substrate G is subjected to decoloring processing. Thereafter, the substrate G is carried into the third heat treatment unit section 28 and subjected to a series of heat treatments (post-bake treatment or the like) in the heat treatment unit blocks (TB) 37 and 38. Note that the substrate transport in the third heat treatment unit section 28 is performed by the transport device 39.
The substrate G is cooled to a predetermined temperature in the third heat treatment unit section 28 and then accommodated in a predetermined cassette C by the transfer device 11 of the cassette station 1.

Next, a resist coating apparatus (CT) 23a as a coating film forming apparatus according to the present invention will be described. FIG. 2 is a front view of the resist coating apparatus (CT) 23a. In FIG. 2, the horizontal direction is the X direction, the vertical direction is the Y direction, and the depth direction is the Z direction.
The resist coating apparatus (CT) 23a holds a substrate G in a horizontal position and can move horizontally in the Z direction, and a resist supply nozzle (hereinafter referred to as a nozzle) disposed above the table 50. ) 51 and nozzle moving means 52 that horizontally moves the nozzle 51 with respect to the substrate G in the Z direction and moves it up and down in the Y direction.

In this configuration, in the resist coating process on the substrate G placed on the placing table 50, the nozzle 51 is first aligned in the horizontal direction by the nozzle moving means 52. Specifically, the nozzle 51 is horizontally moved in the Z direction, and is moved above one end of the substrate G on the mounting table 50. Next, the nozzle 51 is moved downward from the nozzle standby position to the application execution position, and the distance dimension between the ejection port 51a and the surface of the substrate G is set to 50 μm, for example.
Then, the nozzle 51 is horizontally moved in the Z direction while discharging the resist solution in a strip shape from the discharge port 51a, and the substrate G and the nozzle 51 are relatively moved by horizontally moving the mounting table 50 in the direction opposite to the moving direction of the nozzle 51. The substrate is moved horizontally and a resist coating process on the substrate G is performed.

  Here, the raising / lowering movement control of the nozzle 51 by the nozzle moving means 52 will be described in detail. Of the nozzle moving means 52, the vertical movement is performed by the ball screw mechanisms 60 and 70. As shown in the figure, the ball screw mechanisms 60 and 70 are provided on the left and right sides of the mounting table 50, and are configured to support the nozzle 51 from both the left and right sides.

  The ball screw mechanisms 60 and 70 are erected in the Y-axis (vertical axis) direction, and ball screw shafts (first and second ball screw shafts) 61 and 71 each having a spiral ball screw groove formed on the outer periphery. And elevating members (first and second elevating members) 62 and 72 having a nut structure screwed onto the ball screw shafts 61 and 71, respectively. The elevating members 62 and 72 are moved up and down along the shafts 61 and 71 as the ball screw shafts 61 and 71 rotate around the Y axis (vertical axis), respectively. These elevating members 62 and 72 are connected to the left and right sides of the nozzle 51, respectively, and the nozzle 51 moves up and down in conjunction with the elevating operation of the elevating members 62 and 72.

  Furthermore, the ball screw mechanisms 60 and 70 detect motors (first and second motors) 63 and 73 for rotationally driving the ball screw shafts 61 and 71 and the number of rotations of the motors 63 and 73 (output by a counter). Rotary encoders (first and second rotary encoders) 64 and 74. The rotational speeds of the ball screw shafts 61 and 71 detected by the rotary encoders 64 and 74 are output to the control unit (control means) 80, and the control unit 80 determines the rotational speeds of the motors 63 and 73 (shafts 61 and 71). The moving distance of the elevating members 62 and 72 is converted and obtained.

The ball screw shaft 61 and the elevating member 62 are accommodated in a casing (first casing) 65, and the ball screw shaft 71 and the elevating member 72 are accommodated in a casing (second casing) 75. That is, the influence of the ambient temperature on the ball screw shafts 61 and 71 can be avoided.
Preferably, temperature adjusting means (not shown) for adjusting the temperature in the casings 65 and 75 is provided so that the shafts 61 and 71 do not expand or contract due to temperature changes in the casing.

In addition, linear scale mechanisms (first and second linear scale mechanisms) 67 and 77 are provided outside the casings 65 and 75 for measuring the vertical movement distance of the nozzle 51. The linear scale mechanisms 67 and 77 are linear scales 67a and 77a provided along the raising / lowering direction of the nozzle 51, and a scale head 67b provided on the nozzle 51 and moving up and down together with the nozzle 51 with respect to the linear scales 67a and 77a. 77b. For example, the linear scale mechanisms 67 and 77 are configured to measure the length of the glass scale formed on the linear scales 67a and 77a by reading the pitch with the optical sensors of the scale heads 67b and 77b.
That is, the moving distance of the nozzle 51 is measured by the scale heads 67b and 77b. The detection results by the scale heads 67 b and 77 b are output to the control unit 80.

  The nozzle 51 includes a distance sensor (first and second distance detection means) 68 that detects the distance between the left and right sides (one end side and the other end side) of the slit-like discharge port 51a and the upper surface of the substrate G, respectively. 78 are provided symmetrically. These distance sensors 68 and 78 detect when the nozzle 51 is located at the nozzle standby position, and output the result to the control unit 80. That is, the control unit 80 determines whether there is a deviation in the distance from the substrate G on the left and right sides of the nozzle 51 based on the detection results of the distance sensors 68 and 78.

Here, a correction amount calculation method when there is a deviation in the distance to the substrate G on both the left and right sides of the discharge port 51a at the nozzle standby position will be described with reference to FIGS. FIG. 3 is a diagram showing distance dimensions used until the correction amount is obtained, and FIG. 4 is a flowchart until the control unit 80 calculates the correction amount.
Note that the actual distance between the upper surface of the mounting table 50 and the discharge port 51a at the nozzle standby position may differ between the left and right sides of the nozzle 51, but both are set to a specified value of 1000 μm in the calculation. In addition, since the substrate G placed on the mounting table actually has an inclination on the surface and correction including the inclination is necessary, the inclination of the substrate G is schematically shown in FIG. . The distance sensors 68 and 78 are provided symmetrically about a center line (vertical line) M passing through the midpoint of the discharge port 51a of the nozzle 51.

First, the control unit 80 detects the distances S1 and S1 from the upper surface of the substrate G to the upper surfaces of the substrates G by detecting the distances S1 and S1 from the upper surfaces of the substrates G using the distance sensors 68 and 78, respectively. 3) (step S1 in FIG. 4).

Next, a distance a3 from the upper surface of the mounting table 50 to the upper surface of the substrate G on the center line M is obtained by Expression (4) (Step S2 in FIG. 4).

Then, differences a4 and a5 between a1, a2 and a3 are respectively calculated by equations (5) and (6) (step S3 in FIG. 4).

Next, a difference a6 between a3 and the liquid landing target distance R1 is obtained by Expression (7) (Step S4 in FIG. 4). The liquid landing target distance R1 is a distance from the mounting table 50 to the upper surface of the substrate G defined in the processing recipe.

The differences a4 and a5 are converted into the positions of the ball screw shafts 61 and 71 by the equations (8) and (9) to obtain a7 and a8, respectively (step S5 in FIG. 4).

Then, the movement correction amounts a9 and a10 of the elevating members 62 and 72 with respect to the left and right ball screw shafts 61 and 71 are obtained by equations (10) and (11) (step S6 in FIG. 4).

When the correction amounts a9 and a10 are obtained in this way, the control unit 80 applies the correction amounts a9 and a10 to the liquid landing target distance R1 set in the processing recipe, and executes the application of the nozzle 51 from the standby position. Move down to position.
Note that the linear scale mechanisms 67 and 77 are used instead of the rotary encoders 64 and 74 for detecting the movement distance of the nozzle 51 to the application execution position. This is because when the ball screw shafts 61 and 71 are expanded and contracted due to a temperature change, if the up and down movement control is performed based on the outputs of the rotary encoders 64 and 74, the ball screw shafts 61 and 71 cannot move to an accurate height position.

That is, the temperature environment is separated from the ball screw shafts 61 and 71 by the casings 65 and 75, and the movement distance is detected using the linear scale mechanisms 67 and 77 without expansion and contraction, so that the nozzle 51 can be accurately moved from the standby position. It is made so that you can get the distance.
As the nozzle 51 is lowered to the application execution position, the rotary encoders 64 and 74 count the rotation speeds of the motors 63 and 73, respectively, and the count value is used when the nozzle 51 is returned to the standby position.

  As described above, when the nozzle 51 is moved from the nozzle standby position to the application execution position, it is moved downward to the application execution position in consideration of the right / left position correction under the accurate length measurement by the linear scale mechanisms 67 and 77. Is made. As a result, the distance between the ejection port 51a and the upper surface of the substrate G substantially conforms to the processing recipe. Therefore, it is possible to apply the resist solution so that the distance between the slit-like ejection port 51a and the substrate G is a predetermined distance and a desired film thickness.

  Further, when the nozzle 51 is returned to the standby position after the resist solution is applied to the substrate G, the length of the ball screw shafts 61 and 71 may be further changed. Returning to the standby position using the linear scale mechanisms 67 and 77 based on the moving distance including the amount is not accurate. Therefore, the rotary encoders 64 and 74 that can specify the position close to the nozzle standby position by the counter value, and standby position detection sensors (first and second standby position detection means) 66 and 76 that can specify the accurate standby position are provided. Used. The standby position detection sensors 66 and 76 are provided at positions where the nozzle 51 can be accurately detected as shown in FIG. 2, that is, above the ball screw mechanisms 60 and 70, respectively.

Next, control for returning the nozzle 51 to the nozzle standby position will be described based on the flow of FIG.
First, the control unit 80 rotationally drives the motors 63 and 73 in each of the ball screw mechanisms 60 and 70 until the counter outputs of the rotary encoders 64 and 74 become initial values, and the ball screw shafts 61 and 71 rotate. The nozzle 51 is raised to the vicinity of the standby position (step S11 in FIG. 5).

  When the ball screw shafts 61 and 71 are expanded and contracted due to a temperature change, the nozzle 51 is not returned to the accurate standby position, so that the nozzle 51 is moved until the standby position detection sensors 66 and 76 detect the left and right sides of the nozzle 51, respectively. Move (step S12 in FIG. 5). Here, if the standby position detection sensors 66 and 76 are not detecting and reacting during the movement in step 11, they are further moved upward, and if there is already a detected reaction, they are moved downward.

  Both the left and right sides of the nozzle 51 are detected by the standby position detection sensors 66 and 76, and when the movement of the nozzle 51 is stopped by the ball screw mechanisms 60 and 70, the nozzle 51 is returned to an accurate standby position. Then, the counters of the rotary encoders 64 and 74 are reset and the count is in an initial state (step S13 in FIG. 5).

According to the above-described embodiment of the present invention, when the nozzle 51 is lowered from the nozzle standby position to the application execution position, the correction amount is calculated and then the nozzle movement control to which the correction amount is applied is performed. And since the linear scale mechanisms 67 and 77 which are separated from the ball screw mechanisms 60 and 70 and do not expand and contract are used for the detection of the movement amount, accurate movement control can be performed. Therefore, it is possible to apply the resist solution so that the distance between the slit-like ejection port 51a and the substrate G is a predetermined distance and a desired film thickness.
Further, in the return movement from the application execution position to the nozzle standby position, rotary encoders 64 and 74 that can specify a position close to the nozzle standby position by a counter value, and a standby position detection sensor 66 that can specify an accurate standby position, By performing movement control using 76, the nozzle 51 can be moved to an accurate nozzle standby position.

In the above embodiment, the LCD substrate is described as an example of the substrate to be processed. However, the present invention is not limited to the LCD substrate, and a semiconductor wafer, for example, may be applied as the substrate to be processed.
Further, in the configuration of the resist coating apparatus 23a shown in FIG. 2, the configuration in which the substrate G is placed on and placed on the mounting table 50 is shown. However, in the coating film forming apparatus according to the present invention, the configuration is It is not limited. That is, the position of the nozzle 51 can be corrected if the distance between the ejection port 51a and the upper surface of the substrate G can be detected. For example, the substrate G is floated on the mounting table 50 and held in a horizontal posture. It may be configured to.

  The present invention can be applied to a coating film forming apparatus that forms a coating film on an LCD substrate, a semiconductor wafer, or the like, and can be suitably used in the semiconductor manufacturing industry, the electronic device manufacturing industry, and the like.

FIG. 1 is a plan view showing the overall configuration of a resist coating and developing treatment apparatus including a resist coating apparatus as a coating film forming apparatus according to the present invention. FIG. 2 is a front view of the resist coating apparatus provided in the resist coating and developing apparatus of FIG. FIG. 3 is a schematic diagram showing each distance dimension used until the correction amount is obtained. FIG. 4 is a flowchart until the correction amount is calculated by the control unit. FIG. 5 is a flowchart showing the control of raising the nozzle to the nozzle standby position. FIG. 6 is a view for explaining a resist supply nozzle having a slit-like discharge port. FIG. 7 is a view for explaining a ball screw mechanism for moving the nozzle up and down. FIG. 8 is a graph as a measurement result showing the relationship between the temperature change of the ball screw shaft and the discharge position of the nozzle.

Explanation of symbols

23a Resist coating device (coating film forming device)
50 mounting table 51 resist supply nozzle (nozzle)
51a Discharge port 60 Ball screw mechanism 61 Ball screw shaft (first ball screw shaft)
62 Lifting member (first lifting member)
63 Motor (first motor)
64 Rotary encoder (first rotary encoder)
65 Casing (first casing)
66 Standby position detection sensor (first standby position detection means)
67 Linear scale mechanism (first linear scale mechanism)
68 Distance sensor (first distance detection means)
70 Ball screw mechanism 71 Ball screw shaft (second ball screw shaft)
72 Lifting member (second lifting member)
73 Motor (second motor)
74 Rotary encoder (second rotary encoder)
75 Casing (second casing)
76 Standby position detection sensor (second standby position detection means)
77 Linear scale mechanism (second linear scale mechanism)
78 Distance sensor (second distance detection means)
80 Control unit (control means)
G LCD substrate (substrate to be processed)
R resist solution (treatment solution)

Claims (7)

A mounting table for holding the substrate to be processed in a horizontal posture; and a nozzle having a slit-like discharge port extending in the width direction of the substrate to be processed; and processing from the nozzle discharge port to the substrate to be processed In a coating film forming apparatus for applying a liquid in a strip shape,
The first and second ball screw shafts erected in the vertical direction on the left and right sides of the mounting table, respectively, and the first and second ball screw shafts rotate around the vertical axis to move to the ball screw shaft. First and second elevating members that are provided so as to be movable up and down along the left and right sides, and provided on the nozzle, and are subjected to the processing from one end side and the other end side of the slit-like discharge port. First and second distance detecting means for detecting the distance dimension to the substrate, respectively, and control means for performing rotation control of the first and second ball screw shafts,
The control means performs rotation control of the first and second ball screw shafts based on the detection results of the first and second distance detection means, respectively, and corrects the position of the nozzle with respect to the substrate to be processed. A coating film forming apparatus. A first casing accommodating the first ball screw shaft and the first elevating member; a second casing accommodating the second ball screw shaft and the second elevating member; and the first casing outside. A first linear scale mechanism for measuring a moving distance on one end side of the nozzle, and a second linear scale mechanism provided on the outside of the second casing for measuring a moving distance on the other end side of the nozzle. With a linear scale mechanism,
The control means controls the rotation of the first and second ball screw shafts based on the length measurement results by the first and second linear scale mechanisms, and lowers the nozzle from the nozzle standby position to the application execution position. The coating film forming apparatus according to claim 1, wherein the coating film forming apparatus performs the position correction with respect to the substrate to be processed. A first motor that rotationally drives the first ball screw shaft; a second motor that rotationally drives the second ball screw shaft; and a first rotary encoder that detects the rotational speed of the first motor A second rotary encoder that detects the rotation speed of the second motor, a first standby position detection means that detects a state where one end side of the nozzle is located at a nozzle standby position, and the other end side of the nozzle is A second standby position detecting means for detecting a state located at the nozzle standby position,
When the control means returns the nozzle from the application execution position to the nozzle standby position, the control means raises the nozzle to a position where the counter output values of the first and second rotary encoders become initial values. 3. The coating film forming apparatus according to claim 1, wherein the nozzle standby position is specified by moving the nozzle to a position where the second standby position detection unit detects the nozzle. 4.   The coating film forming apparatus according to any one of claims 1 to 3, further comprising temperature adjusting means for controlling the temperature in the first and second casings. A mounting table for holding the substrate to be processed in a horizontal position; first and second ball screw shafts erected vertically on the left and right sides of the mounting table; and the first and second ball screw shafts The first and second elevating members that move up and down along the ball screw shaft by a rotational movement around the vertical axis, and the width of the substrate to be processed supported by the first and second elevating members from the left and right sides A nozzle formed with a slit-like discharge port extending in a direction, and first and second distance detection means provided in the nozzle for detecting a distance dimension from the discharge port to the substrate to be processed, A method for controlling a coating film forming apparatus for applying a processing liquid to a substrate to be processed in a strip shape from a discharge port of the nozzle,
Detecting the distance dimensions between the one end side and the other end side of the slit-like discharge port and the substrate to be processed by the first and second distance detecting means;
Based on the detection results of the first and second distance detecting means, the rotation control of the first and second ball screw shafts is performed, respectively, and the step of correcting the position of the nozzle with respect to the substrate to be processed is executed. A method for controlling a coating film forming apparatus. The coating film forming apparatus includes first and second linear scale mechanisms for measuring the movement distances on one end side and the other end side of the nozzle, respectively.
In the step of correcting the position of the nozzle with respect to the substrate to be processed based on the detection results of the first and second distance detection means,
The rotation control of the first and second ball screw shafts is performed based on the length measurement results by the first and second linear scale mechanisms, respectively, and the nozzle is moved downward from the nozzle standby position to the application execution position. A method for controlling a coating film forming apparatus according to claim 5. The coating film forming apparatus includes: a first motor that rotationally drives the first ball screw shaft; a second motor that rotationally drives the second ball screw shaft; and a rotational speed of the first motor. A first rotary encoder for detecting; a second rotary encoder for detecting the rotational speed of the second motor; and a first standby position detecting means for detecting a state in which one end of the nozzle is positioned at a nozzle standby position; A second standby position detection sensor for detecting a state in which the other end side of the nozzle is positioned at the nozzle standby position,
In the step of returning the nozzle from the application execution position to the nozzle standby position after the application process to the substrate to be processed,
Raising the nozzle to a position where the counter output values of the first and second rotary encoders become initial values;
The nozzle standby position is specified by executing the step of moving the nozzle to a position where the first and second standby position detecting means detect the nozzle. For controlling the applied coating film forming apparatus.

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