JP4402421B2 - Coating film forming method and coating film forming apparatus - Google Patents

Description

  The present invention relates to a coating film forming method and a coating film forming apparatus, and more particularly to a technique for forming a coating film on a substrate by discharging a fluid film material from a die as a sheet-like film.

  A technique for forming a coating film by applying a fluid film material such as resin on a substrate is used in various fields. For example, in a process for manufacturing a display product such as a plasma display panel, a step of forming various coating films on a substrate is required. As a method for forming a uniform coating film in a relatively wide area, a so-called die coat method is generally used. In this method, a coating film made of a film material discharged in a sheet form on a substrate while scanning a die having a function of discharging a fluid film material such as a resin as a sheet film on the substrate The work to form is performed.

For example, Patent Document 1 below discloses a coating film forming method for forming a uniform coating film without unevenness using a fluid film material having a high viscosity. In general, if there are steps, slopes, and irregularities on the surface of the substrate on which the coating film is to be formed, it becomes difficult to form a uniform coating film without unevenness. For this reason, in the coating film forming method disclosed in Patent Document 1 below, the height of the upper surface of the substrate on which the coating film is to be formed is measured in advance using a displacement meter, Based on this, a technique of applying a sheet-like film on the substrate while moving the die up and down is employed.
Japanese Patent Laid-Open No. 11-165111

  In the manufacturing process of industrial products, in order to control quality, an inspection process is usually performed for each lot. For this reason, when the process of forming a coating film on some base material is implemented, the thickness of the coating film actually formed is measured, and the process of inspecting whether the measurement result satisfies a predetermined standard is performed. Is preferred. Therefore, in the case of an apparatus provided with a displacement meter, such as the coating film forming apparatus disclosed in the above-mentioned Patent Publication 1, using this displacement meter, the height of the upper surface of the substrate before film formation, A method has been proposed in which the height of the upper surface of the coating film is measured and the thickness of the coating film is determined based on the difference between the two. If this method is used, not only the coating film can be formed, but also the thickness of the formed coating film can be measured. However, in plasma display panel parts and the like, the material of the substrate on which the film is to be formed differs greatly from the material of the coating film, so that it has been difficult to perform an appropriate film thickness measurement with the conventionally proposed methods. there were.

  Therefore, the present invention provides a coating film forming method and a coating film forming apparatus having a function of performing an appropriate film thickness measurement according to the material of the base material to be formed of the film and the material of the coating film itself. Objective.

(1) A first aspect of the present invention is a coating film forming method for forming a coating film on a substrate by discharging a sheet-like film from a die.
A stage of fixing a substrate on a stage and arranging a die having a function of discharging a fluid film material in a sheet shape above the substrate;
A base material measuring step for measuring the height on the measurement line along the moving direction of the upper surface of the base material while moving the base material or the die along the predetermined moving direction;
While the die is moved up and down according to the height measured in the base material measurement stage, the base material or the die is moved along the moving direction in a state where the fluid film material is discharged from the die into a sheet shape. According to the coating film forming step of forming a coating film by applying a sheet-like film on the upper surface of the substrate,
While moving the substrate or die along the moving direction, a coating film measurement stage for measuring the height on the measurement line of the coating film upper surface,
Based on the difference between the height measurement value in the base material measurement stage and the height measurement value in the coating film measurement stage, a film thickness calculation stage for calculating the thickness of the coating film in each part along the measurement line; ,
And do
In the substrate measurement stage and the coating film measurement stage, a smoothing process for spatially smoothing the obtained measurement values is performed, and the degree of smoothing is determined according to the substrate measurement stage and the coating film measurement. It is set to be different depending on the stage.

(2) According to a second aspect of the present invention, in the coating film forming method according to the first aspect described above,
The coating film formation stage and the coating film measurement stage are performed simultaneously by the same movement operation.

(3) According to a third aspect of the present invention, in the coating film forming method according to the first or second aspect described above,
Replacing the measurement values at individual measurement points along the measurement line with simple averages or weighted average values of measurement values at multiple measurement points included in a neighboring section with a predetermined width centered on the relevant point Thus, the smoothing process is executed, and the width of the neighboring section is set to be different between the smoothing process in the base material measurement stage and the smoothing process in the coating film measurement stage.

(4) According to a fourth aspect of the present invention, in the coating film forming method according to the first to third aspects described above,
The computer calculates the deviation between the preset reference film thickness and the film thickness obtained in the film thickness calculation stage, and if the obtained deviation exceeds a predetermined threshold value, the formed coating film is regarded as defective. A defect determination stage for executing the determination process is further added.

(5) According to a fifth aspect of the present invention, in the coating film forming method according to the first to fourth aspects described above,
Based on the film thickness obtained in the film thickness calculation stage , an image showing the cross-sectional shape of one or both of the coating start end and the coating end end of the coating film is created on the computer, and processing for presenting it is executed. An end shape presentation step is further added.

(6) A sixth aspect of the present invention is the coating film forming method according to the first to fifth aspects described above,
A substrate for a back plate of a plasma display panel, which has a two-layer structure of a glass layer serving as a base and a dielectric layer made of a glass paste containing a pigment, and in which electrodes are embedded at predetermined positions in the dielectric layer Is fixed on the stage as a base material, and a layer mainly composed of glass paste to be a rib layer is formed on the upper surface of the dielectric layer as a coating film,
The smoothing in the smoothing process in the base material measurement stage is set so that the degree of smoothing is higher than the smoothing in the smoothing process in the coating film measurement stage.

(7) The seventh aspect of the present invention is a coating film forming apparatus for forming a coating film on a substrate by discharging a sheet-like film from a die.
A stage for fixing the substrate;
A support provided above the stage;
A die attached to the support so as to be movable in the vertical direction and having a function of discharging the fluid film material in a sheet form,
Die moving means for moving the die up and down with respect to the support;
A displacement meter attached to the support and measuring the distance to the object placed on the stage;
Scanning means for scanning the die and the displacement meter with respect to the substrate on the stage by moving the stage or the support along a predetermined movement direction;
A control means for controlling the scanning means, the die, the die moving means, and taking in the measured value of the displacement meter,
In the control means,
A base material measurement unit that captures a distance measurement value to the top surface of the base material measured by the displacement meter while causing the scanning means to perform scanning;
A first smoothing processing unit for performing a first smoothing process for spatially smoothing a distance measurement value at each position along a predetermined measurement line captured by the base material measurement unit;
The die moving means is controlled in accordance with the distance measurement value smoothed by the first smoothing processing unit to cause the scanning means to perform scanning while moving the die up and down, and the fluid film material is formed into a sheet form from the die. In a discharged state, a coating film forming unit that forms a coating film by applying a sheet-like film on the upper surface of the substrate;
A coating film measuring unit that captures a distance measurement value to the top surface of the coating film measured by the displacement meter while causing the scanning unit to perform scanning;
A second smoothing processing unit for performing a second smoothing process for spatially smoothing the distance measurement value at each position along the measurement line captured by the coating film measuring unit;
Based on the difference between the distance measurement value after the smoothing processing by the first smoothing processing unit and the distance measurement value after the smoothing processing by the second smoothing processing unit, at each position along the measurement line A film thickness calculator for calculating the thickness of the coating film;
The smoothing degree in the first smoothing process and the second smoothing process can be set separately.

(8) An eighth aspect of the present invention is the coating film forming apparatus according to the seventh aspect described above,
The coating film forming unit and the coating film measuring unit cooperate with each other to cause the scanning unit to perform scanning, and the formation of the coating film by the coating film forming unit and the measurement by the coating film measuring unit are simultaneously performed by one scanning. It is what was done.

(9) A ninth aspect of the present invention provides the coating film forming apparatus according to the seventh or eighth aspect described above,
Replacing the measurement values at individual measurement points along the measurement line with simple averages or weighted average values of measurement values at multiple measurement points included in a neighboring section with a predetermined width centered on the relevant point Thus, the smoothing process is executed, and the first smoothing process and the second smoothing process can be set so that the widths of the neighboring sections are different.

(10) According to a tenth aspect of the present invention, in the coating film forming apparatus according to the seventh to ninth aspects described above,
A defect that determines the deviation between the preset reference film thickness and the film thickness calculated by the film thickness calculator, and determines that the formed coating film is defective when the calculated deviation exceeds a predetermined threshold value. The determination unit is further provided in the control means.

(11) An eleventh aspect of the present invention is the coating film forming apparatus according to the seventh to tenth aspects described above,
Based on the film thickness obtained by the film thickness calculation unit, an image showing the cross-sectional shape of one or both of the coating start end and the coating end end of the coating film is created, and an end shape presenting unit for presenting this is shown. Further, it is provided in the control means.

  (12) According to a twelfth aspect of the present invention, there is provided a program for causing a computer to function as control means in the coating film forming apparatus according to the seventh to eleventh aspects described above, and the program can be read by the computer. It can be recorded and distributed on a medium.

  According to the coating film forming method and the coating film forming apparatus according to the present invention, the step of measuring the height of the upper surface of the base material on which the film is to be formed and the step of measuring the height of the upper surface of the actually formed coating film And smoothing processing for spatially smoothing the obtained measurement values, and the degree of smoothing with respect to the measurement value on the upper surface of the substrate and the smoothing with respect to the measurement value on the upper surface of the coating film. Since the degree of conversion is set independently, smoothing processing according to each material is possible, and film formation is possible regardless of the material of the base material or the coating film itself. At the same time, an appropriate film thickness can be measured.

  Hereinafter, the present invention will be described based on the illustrated embodiments.

<<< Chapter 1: Physical Structure and Basic Operation of Coating Film Forming Apparatus >>>
First, the physical structure and basic operation of the coating film forming apparatus according to the basic embodiment of the present invention will be described. FIG. 1 is a perspective view showing a physical structure portion of the coating film forming apparatus. As illustrated, this apparatus is configured by arranging various physical components on a flat base plate 100. Here, for convenience of explanation, an XYZ three-dimensional coordinate system is defined as shown in the figure. The upper surface of the pedestal plate 100 is a surface included in the XY plane, and the Z axis is oriented in the vertical direction with respect to the upper surface of the pedestal plate 100.

  A stage 120 is disposed above the pedestal plate 100 so as to be movable in the X-axis direction. In the case of the illustrated embodiment, two transport rails 131 and 132 extending in a direction parallel to the X axis are provided on the upper surface of the pedestal plate 100, and a slider 133 attached to the lower surface of the stage 120. However, by sliding on the transport rails 131 and 132, the stage 120 can be moved in the X-axis direction. The stage 120 is a plate-like member on which an upper surface of the substrate S (a target on which a coating film is to be formed: a flat substrate in this example) can be mounted and is parallel to the XY plane. It is arranged to be. Therefore, the substrate S placed and fixed on the upper surface of the stage 120 can also be moved in the X-axis direction together with the stage 120 while being maintained in a horizontal state (a state parallel to the XY plane).

  A pair of side wall portions 111 and 112 are fixed to the upper surface of the pedestal plate 100, and a bridge support 113 is attached between the side wall portions 111 and 112. The bridge support 113 is provided so as to bridge the side wall portions 111 and 112 and has a structure straddling the stage 120. A die 140 is attached to one side (back of the figure) of the bridge support 113, and three sets of displacement meters 151 to 153 are attached to the other side (front of the figure). Although the displacement meters 151 to 153 are fixed to the bridge support 113, the die 140 is attached to the bridge support 113 so as to be movable in the vertical direction (Z-axis direction).

  As will be described later, the stage 120 is moved in the X-axis direction by scanning means (not shown). As a result, the base material S placed and fixed on the stage 120 moves in the X-axis direction so as to pass under the bridge support 113, so that the base 140 is displaced by the die 140 and the displacement meters 151 to 153. The upper surface of the material S is scanned. L1 to L3 indicated by alternate long and short dash lines on the substrate S are measurement lines to be measured by the displacement meters 151 to 153, respectively. Each of the displacement meters 151 to 153 is a component having a function of measuring a distance to an object existing immediately below, but in the process of moving the substrate S in the X-axis direction by a scanning unit, the displacement meter 151. ˜153 can sequentially measure and output the distance to each position along the measurement lines L1 to L3, respectively.

  2 is a side sectional view showing a state in which the main part of the apparatus shown in FIG. 1 is cut along the measurement line L1, and a coating film is formed on the upper surface of the substrate S placed on the stage 120. The process to do is shown. The die 140 is a structure that functions as a die for discharging the fluid film material M1 (for example, liquid resin). Actually, the fluid film material M1 is supplied into the die 140 from a pump (not shown), and the fluid film material M1 is discharged downward by the pressure applied from the pump. An elongated slit is formed in the lower surface of the die 140 in the Y-axis direction (perpendicular to the paper surface of FIG. 2), and the fluid film material M1 in the die 140 moves downward from the slit as a sheet-like film M2. Is discharged. That is, the sheet-like film M2 shown in FIG. 2 falls to the upper surface of the base material S while a sheet having a width in the depth direction in the figure is formed. In this state, when the stage 120 is gradually moved in the X-axis direction (the direction of the arrow X in FIG. 2), the discharged sheet-like film M2 is applied onto the upper surface of the substrate S as shown in the drawing. It is applied as M3. Here, a pump and a supply pipe for supplying the fluid film material M1 to the die 140 are not shown.

  Although the die 140 is attached to the bridge support 113, it is not fixed and is movable in the vertical direction (Z-axis direction indicated by the arrow Z in FIG. 2), as will be described later. In addition, the structure can be moved up and down by the die moving means. Although a specific mechanism of the die moving means is not shown here, any mechanism can be used as long as the die 140 can be moved in the vertical direction with respect to the bridge support 113. It doesn't matter. For example, a slide rail is provided on the side surface of the bridge support 113, a slider fitted to the slide rail is provided on the die 140 side, and a motor embedded in the bridge support 113 is used to make the die 140 side The slider may be driven up and down along the slide rail on the bridge support 113 side.

  On the other hand, the displacement meters 151 to 153 are components having a function of measuring a distance to an object placed on the stage 120, and are so-called gap sensors. In general, a laser displacement meter is preferably used as the sensor, but any sensor capable of measuring distance may be used. FIG. 2 shows an example in which the distance D to the upper surface of the coating film M3 existing immediately below the displacement meter 151 is measured. In practice, a laser light source, an optical system, a light receiving element, and the like are incorporated in the displacement meter 151, but these components are not shown here.

  As shown in the perspective view of FIG. 1, the displacement meters 151 to 153 are arranged above the measurement lines L1 to L3, respectively, and distance measurement is performed at each position on each measurement line L1 to L3. In the illustrated example, each of the displacement meters 151 to 153 has a function of measuring a distance immediately below, but the purpose of the displacement meters 151 to 153 is to measure lines L1 to L3 for the object on the stage 120, respectively. Therefore, it is not always necessary to measure the distance directly below, and a displacement meter that measures the distance in the diagonally downward direction may be used.

  The die 140 is movable in the vertical direction with respect to the bridge support body 113. Even when a step, an inclination, an unevenness, etc. exist on the upper surface of the base material S, it is possible to form a good film. It is to do. For example, consider the case where the upper surface of the substrate S is inclined as shown in the side sectional view of FIG. In this case, if the die 140 is fixed to the bridge support body 113, the height of the discharge port of the die 140 is always maintained at the level V1. Therefore, the distance d (so-called gap) between the discharge port and the upper surface of the substrate S differs depending on each part on the substrate S. Thus, when the distance d is different at each part on the substrate S, it is difficult to form a uniform coating film, which is not preferable. The fact that the die 140 can be moved up and down is a consideration for avoiding such adverse effects.

  That is, as shown in FIG. 3, when scanning is performed to move the stage 120 in the X-axis direction without discharging the fluid film material from the die 140, the measurement lines L <b> 1 to L <b> 1 are respectively measured by the displacement meters 151 to 153. The distance D to the upper surface of the base material S at the position along L3 can be measured. In the case of the illustrated example, the upper surface position of the base material S immediately below the displacement meter 151 is gradually lowered by scanning in the X-axis direction, so that the measured value of the distance D gradually increases. When the distance D in each part can be measured in this way, as shown in FIG. 4, this time, scanning is performed to move the stage 120 in the X-axis direction while discharging the fluid film material M1 from the die 140 as a sheet-like film M2. And a process of forming the coating film M3 on the upper surface of the substrate S is performed. However, at this time, the die 140 is moved in the vertical direction according to the distance D measured in the stage shown in FIG. Specifically, the measured value of the distance D obtained in the stage shown in FIG. 3 gradually increases with the scanning in the X-axis direction. Therefore, in the film formation stage shown in FIG. Along with scanning, the die 140 may be gradually moved downward. Then, the height of the discharge port of the die 140 can be changed as indicated by level V2, and the coating film is maintained in a state where the distance d between the discharge port and the upper surface of the substrate S is kept constant. M3 can be formed.

  3 and 4 are examples in the case where the upper surface of the substrate S is inclined. When a step or unevenness is generated on the upper surface of the substrate S, the die 140 is moved up and down according to the step or unevenness. By moving it, the distance d can be kept constant. In the illustrated example, the three displacement meters 151 to 153 can obtain measured values at positions on the three measurement lines L1 to L3. Therefore, for example, three measurement lines are used for movement control of the die 140. What is necessary is just to use the average value of the measured value on L1-L3. Alternatively, the left and right inclinations of the die 140 may be determined based on the measurement values on the three measurement lines L1 to L3. Of course, in the perspective view of FIG. 1, if the die 140 is composed of three independent parts such as a right part, a central part, and a left part, and each can be moved up and down independently, a displacement meter The vertical movement of the right part is controlled based on the measurement value by 151, the vertical movement of the central part is controlled based on the measurement value by the displacement meter 152, and the vertical movement of the left part is controlled based on the measurement value by the displacement meter 153. It becomes possible to do.

  In this way, the height of the upper surface of the substrate S is measured in the stage before film formation, and the film formation is performed while moving the die 140 up and down in accordance with the measured value in the film formation stage. For example, a coating film can be formed in a state where the distance d between the discharge port of the die 140 and the upper surface of the substrate S is kept constant, and a high-quality film having a uniform film thickness can be formed. The advantage of being able to do it is obtained.

  Another advantage of such a method is that the thickness of the formed coating film M3 can be measured using the displacement meters 151-153. The principle of thickness measurement will be described with reference to the side sectional views of FIGS.

  Now, as shown in FIG. 5, in the previous stage of film formation, height measurement at each position along the measurement line L1 on the upper surface of the substrate S (measurement of the distance D by the displacement meter 151) has been performed. Try. Here, the step of measuring the height of each position on the upper surface of the base material S will be referred to as a “base material measurement step”. The purpose of this base material measurement step is to measure the height of the upper surface of the base material S that is the target of film formation in advance, as described above, and to discharge the fluid film material M1 from the die 140. Without performing the process, the process of taking in the measurement value of the displacement meter 151 is performed while performing the scanning that gradually moves the base material S to the left (X-axis direction) in the drawing.

  If the measurement values are taken in at a constant cycle while scanning is performed at a constant speed, positions P1, P2, P3,..., Pi-1, Pi, Pi + 1,. A measured value D can be obtained for each Pn. Here, these measured values are represented as D (P1), D (P2), D (P3), ..., D (Pi-1), D (Pi), D (Pi + 1), ..., D (Pn). I will represent it. As in the example shown in FIG. 5, when the upper surface of the base material S is a completely horizontal surface, the measured values D are all equal. Since the inclination is generated or the uneven structure is present, the value of the measured value D changes for each position.

  Subsequently, as shown in FIG. 6, while the fluid film material M <b> 1 is discharged as a sheet-like film M <b> 2 from the die 140, scanning is performed to gradually move the base material S to the left (X-axis direction) in the figure. Thereby, the process which forms the coating film M3 on the upper surface of the base material S is performed. At the same time, if the measurement values of the displacement meter 151 are taken in at a constant cycle, positions Q1, Q2, Q3,..., Qi-1, on the coating film M3, which are arranged at regular intervals on the measurement line L1. Measured values D can be obtained for Qi, Qi + 1,. These measured values are expressed as D (Q1), D (Q2), D (Q3),..., D (Qi-1), D (Qi), D (Qi + 1),. To do. If the timing for taking in the measured values is adjusted well, the position Q1 can be directly above the position P1, and the i-th position Qi can be directly above the i-th position Pi. Here, the step of measuring the height of each position on the upper surface of the coating film M3 formed on the substrate S in this way is referred to as a “coating film measurement step”.

  Thus, when the measurement value at the base material measurement stage and the measurement value at the coating film measurement stage are obtained, the thickness of the coating film M3 at the position can be obtained by calculating the difference between the measurement values at the corresponding positions. it can. For example, if the film thickness at the position P1 is expressed as T (P1), it can be obtained by the calculation T (P1) = D (P1) −D (Q1). In general, the film thickness at the i-th position can be obtained by the calculation T (Pi) = D (Pi) −D (Qi).

  As described above, the method for obtaining the film thicknesses at the n positions P1 to Pn on the measurement line L1 using the displacement meter 151 has been described. However, using the displacement meters 152 and 153, individual film thicknesses on the measurement lines L2 and L3 are described. The film thickness at the position can also be obtained by a similar method. The film thickness value obtained in this way is a film thickness value at a specific position discretely distributed on the coating film M3 formed on the two-dimensional plane, but the distance measurement value capturing period can be set short, If the number of displacement meters to be installed is increased, the film thickness value can be obtained for each specific position with higher density.

<<< Chapter 2: Circumstances that prevent proper film thickness measurement >>>
As described above, the physical structure and the basic operation of the coating film forming apparatus according to the basic embodiment of the present invention have been described. However, in this case, the proper film thickness measurement cannot be performed only by the basic operation described above. The situation that exists will be described with a specific example.

  Here, as an example of such a case, consider a case where the above-described coating film forming apparatus is used in a manufacturing process of a back plate for a plasma display panel. A back plate for a general plasma display panel is a part having a structure as shown in a side sectional view of FIG. 7, and includes a glass layer 10 serving as a base, and a dielectric layer 11 formed of a glass paste containing a pigment. The electrode 12 embedded in the dielectric layer 11, the rib layer 13 formed at a predetermined interval on the upper surface of the dielectric layer 11, and the phosphor layer 14 formed between adjacent rib layers (usually R, The phosphors of the three primary colors G and B are arranged in this order). Here, the rib layer 13 is a layer containing glass paste as a main component, and functions to form boundary walls of individual pixels. Usually, the thickness is required to be 100 μm or more. Therefore, in order to form this rib layer 13, it is common to perform die coating using the coating film forming apparatus having the basic structure described above.

  That is, as shown in the side sectional view of FIG. 8, it has a two-layer structure of a glass layer 10 serving as a base and a dielectric layer 11 (electrode 12 is embedded) made of a glass paste containing a pigment. On the substrate, a layer 15 mainly composed of glass paste was formed as a coating film, and after solidifying the layer 15, a predetermined portion (portion for forming the phosphor layer 14) was removed by sandblasting and remained. A step of making the portion into the rib layer 13 is performed. In such a process, a substrate having a two-layer structure of the glass layer 10 and the dielectric layer 11 is placed and fixed on the stage 120 as the base material S, and the fluidity for forming the layer 15 from the die 140. The film material M1 is discharged. Therefore, in the case of the coating film forming apparatus having the structure shown in FIG. 1, first, in the base material measurement stage, a process of measuring the height of the upper surface of the dielectric layer 11 is executed, and subsequently, simultaneously with the coating film formation stage. The coating film measurement step is executed, the process of measuring the height of the upper surface of the layer 15 (coating film) just formed is executed, and the thickness of the layer 15 is obtained by calculating the difference between the measured values. become.

  However, when applied to such a case, proper film thickness measurement cannot be performed only by the basic operation described above. The root cause is that the fluidized layer 15 is applied to the upper surface of the dielectric layer 11 that has been solidified by the drying / firing process. As described above, the dielectric layer 11 is made of a glass paste containing a pigment, and has a form in which the pigment is scattered in a glass particle having a translucency of about several μm. In the process of forming the dielectric layer 11, first, a step of applying a glass paste layer containing a pigment on the glass layer 10 is performed. In the stage immediately after this coating process, the coating layer is in a fluid state and its surface is smooth. However, after that, through the drying and firing processes, the solvent and the like are volatilized, and fine irregularities are formed on the surface of the dielectric layer 11. As described above, fine irregularities of about several μm are formed on the upper surface of the solidified dielectric layer 11 and the main component is a glass paste, so that the dielectric layer 11 as a whole is translucent. It has unique properties. On the other hand, the layer 15 formed on the upper surface of the dielectric layer 11 is a fluid material when discharged from the die 140, and the upper surface is smoother than the upper surface of the dielectric layer 11. is there. However, since it is a film formed in a process of applying the sheet-like film M2 discharged from the die 140 to the upper surface of the dielectric layer 11, the end portions thereof, that is, the application start end and the application end end are Compared with other parts, the thickness is likely to fluctuate.

  For example, FIG. 9 is an enlarged side sectional view showing the shape of the end 15T (in this example, the coating start end) of the layer 15 formed on the dielectric layer 11. In this example, the end 15T is thicker than the other portions of the layer 15. Of course, depending on the case, the thickness of the end portion 15T may be thinner than the other portions. Similarly, the end of the coating tends to be fluctuated such that the thickness of the end becomes thicker or thinner than other parts. As described above, if the thickness of the end 15T of the layer 15 varies, the end 15T may be peeled off from the upper surface of the dielectric layer 11 during the subsequent firing. Therefore, as shown in FIG. 8, at the stage where the layer 15 is formed on the upper surface of the dielectric layer 11, an inspection is performed to confirm the uniformity of the film thickness of the layer 15, particularly the uniformity of the film thickness at the end portion. It is very important to do.

  As described above, the coating film forming apparatus shown in FIG. 1 has a function of forming the coating film M3 on the substrate S and measuring the film thickness of the formed coating film M3. However, when the coating film is formed by a combination of materials as shown in FIG. 8, an appropriate film thickness measurement cannot be performed only by the basic operation described above. The first reason is that, as described above, fine irregularities of about several μm are formed on the upper surface of the solidified dielectric layer 11, whereas the layer 15 having fluidity before solidification is formed. Since the upper surface is in a relatively smooth state, when the distance to the uneven surface on the upper surface of the dielectric layer 11 is faithfully measured in the base material measurement stage, very fine thickness fluctuations are detected. is there. Of course, in the sense that only the accuracy is required for the thickness measurement value, such a very small thickness variation detection shows an accurate measurement result. However, the rib 13 of the back plate for the plasma display panel is used. In consideration of the purpose of forming the film, it is not preferable to detect even such a very small thickness variation, and an appropriate film thickness measurement cannot be performed.

  And the 2nd reason is because the dielectric layer 11 is comprised with the glass paste containing a pigment as above-mentioned, and the measured value in a base-material measurement step does not necessarily become a correct measured value. That is, since the dielectric layer 11 has a special structure in which the glass paste portion has translucency but the pigment portion has light shielding properties, as a whole, It will exhibit a translucent nature. However, the result of distance measurement by a laser displacement meter or the like does not indicate the distance to the surface of the glass paste that transmits light, but indicates the distance to the pigment that reflects light. For example, if the pigment present at a specific measurement location irradiated with a laser is in a shallow position, the laser light will be reflected by the pigment in this shallow position, so that a relatively short distance can be obtained as a measurement result. Become. Conversely, if the pigment present at a specific measurement location irradiated with the laser is in a deep position, the laser light will be reflected by the pigment in this deep position, so a relatively long distance can be obtained as a measurement result. become. As described above, the measurement result of the distance by the displacement meter varies depending on the pigment distribution depth, and thus is not necessarily a correct measurement value.

  In the above, the case of forming the rib 13 of the back plate for the plasma display panel has been exemplified, but in short, the basic operation described above depends on the inherent properties of the material of the base material to be formed and the material of the coating film itself. In many cases, there are circumstances in which proper film thickness measurement cannot be performed. The present invention proposes a technique that enables an appropriate film thickness measurement even in such a situation.

<<< Chapter 3: Features of the Present Invention >>>
The coating film forming method based on the basic principle described in Chapter 1 is a method of forming a coating film on a substrate by discharging a sheet-like film from a die, and includes the following steps. First, the first stage is a preparatory stage in which the base 140 is fixed on the stage 120 and the die 140 having a function of discharging the fluid film material M1 in the form of a sheet is disposed above the base S. The second stage is a base material measurement stage in which the height on the measurement lines L1 to L3 along the X-axis direction on the upper surface of the base material S is measured while performing a scan for moving the stage 120 in the X-axis direction. is there. The following third stage is the stage 120 in a state where the fluid film material M1 is discharged from the die 140 into a sheet shape while moving the die 140 up and down according to the height measured in the base material measurement stage. Is a coating film forming stage in which scanning is performed in the X-axis direction to apply the sheet film M2 on the upper surface of the substrate S to form the coating film M3. Simultaneously with this coating film forming stage, a fourth stage, that is, a coating film measuring stage for measuring the height of the upper surface of the formed coating film M3 on the measurement lines L1 to L3 is executed. And as the last 5th step, based on the difference between the height measurement value in the substrate measurement step and the height measurement value in the coating film measurement step, the coating film M3 in each part along the measurement lines L1 to L3 The film thickness calculation stage for performing the calculation for determining the film thickness is executed.

  A feature of the present invention is that a smoothing process for spatially smoothing the obtained measurement values is performed in the base material measurement step and the coating film measurement step described above, and the degree of smoothing ( The spatial range to be smoothed) is set to be different between the base material measurement stage and the coating film measurement stage. Specifically, if the layer 15 as shown in FIG. 8 is formed and the film thickness is measured, the base material measurement step for measuring the height of the upper surface of the dielectric layer 11 is performed. Also in the coating film measurement stage in which the height of the upper surface of the formed layer 15 is measured, a smoothing process for spatially smoothing each measurement value is performed, and the smoothing in the former is more preferable. What is necessary is just to set so that the degree of smoothing may become higher than the smoothing in the latter (so that the spatial range used as smoothing object becomes wide). If the level of smoothing in the former, that is, the base material measurement stage for measuring the height of the upper surface of the dielectric layer 11 is increased, smoothing over a wider range can be performed, and the fineness due to surface irregularities can be reduced. Variations in thickness will be excluded, and variations that occur according to the distribution depth of the pigment will be averaged.

  Hereinafter, this feature will be described based on the illustrated embodiment. FIG. 10 is a block diagram showing the overall configuration of a coating film forming apparatus according to an embodiment of the present invention. This apparatus is an apparatus for forming a coating film on a substrate by discharging a sheet-like film from a die, and as shown, a support 110, a stage 120, a scanning means 130, a die 140, a displacement meter 150, It is comprised from each component of the die moving means 160 and the control means 170. FIG. The physical components shown in FIG. 1 are an example in which the support 110, the stage 120, the scanning means 130, the die 140, and the displacement meter 150 are realized with specific structures.

  The stage 120 is a component having a function of fixing the base material S that is a formation target of the coating film, and is the same component as the stage 120 shown in FIG. On the other hand, the support 110 is a component provided above the stage 120 and has a function of supporting the die 140 and the displacement meter 150, and corresponds to the bridge support 113 shown in FIG. The die 140 is the same component as the die 140 shown in FIG. 1. As described above, the die 140 is attached to the support 110 so as to be movable in the vertical direction. It is a component having a function of discharging in a shape. The die moving means 160 is a component that moves the die 140 in the vertical direction with respect to the support 110, although not shown as a specific component in FIG. The displacement meter 150 is a component that is attached to the support 110 and measures the distance to the object placed on the stage 120, and corresponds to the displacement meters 151 to 153 shown in FIG.

  The scanning unit 130 is a component that scans the die 140 and the displacement meter 150 with respect to the substrate S on the stage 120 by moving the stage 120 or the support 110 along a predetermined movement direction. In the embodiment shown in FIG. 1, conveyance rails 131 and 132 and a slider 133 used for moving the stage 120 in the X-axis direction, and a driving mechanism (not shown) correspond to the scanning unit 130. It turns out that. However, the scanning unit 130 does not necessarily perform scanning by moving the stage 120 side. Conversely, even if scanning is performed by moving the support 110 side (the die 140 and the displacement meter 150 side). It doesn't matter. In short, the scanning unit 130 has a function of scanning the die 140 and the displacement meter 150 with respect to the substrate S by relatively moving the die 140 and the displacement meter 150 and the substrate S on the stage 120. As long as the above can be fulfilled, it may be realized by any means.

  The control unit 170 is a component not shown in FIG. 1, but has a function of controlling the scanning unit 130, the die 140, and the die moving unit 160 and capturing the measurement value of the displacement meter 150. It plays a role of controlling the entire apparatus. Here, for convenience of explanation, the control means 170 is used as a base material measuring unit 171, a first smoothing processing unit 172, a coating film forming unit 173, a coating film measuring unit 174, a second smoothing processing unit 175, a film. Although it will be considered as a set of eight functional blocks including a thickness calculation unit 176, a defect determination unit 177, and an end shape presentation unit 178, this control means 170 is actually connected to a general-purpose computer such as a personal computer by a sequencer. It can be configured by connecting a circuit or the like and incorporating a dedicated program. In the block diagram of FIG. 10, solid arrows indicate that electrical signals are exchanged between the block components, and alternate long and short dash arrows indicate physical communication between the block components. This shows that a moving operation is performed.

  The base material measurement unit 171 causes the scanning unit 130 to perform scanning (in the case of FIG. 1, while gradually moving the stage 120 in the X-axis direction), and the upper surface of the base material S measured by the displacement meter 150. The process of taking the distance measurement value up to is performed. For example, in the case of the example shown in FIG. 5, the measurement values D (P1) and D (P2) are the measurement values for the measurement points P1, P2, P3,..., Pi-1, Pi, Pi + 1,. , D (P3), ..., D (Pi-1), D (Pi), D (Pi + 1), ..., D (Pn).

  The first smoothing processing unit 172 performs a first smoothing process for spatially smoothing the distance measurement value at each position along the predetermined measurement line captured by the base material measurement unit 171. carry out. Specifically, by replacing the measurement value at each measurement point along the measurement line with the average value of the measurement values at a plurality of measurement points included in a neighboring section having a predetermined width centered on the point. Smoothing processing can be executed. This is a smoothing process in which a so-called smoothing filter is applied to each measurement value.

  Here, a specific example of the smoothing process by such a method will be described with reference to FIG. Now, as shown in the upper part of FIG. 11, it is assumed that a series of measurement values has been taken in, and a new value DD (Pi) after the smoothing process is obtained for the i-th measurement value D (Pi) among them. Let's explain the principle we want. In this case, first, as a parameter indicating the degree of smoothing, the width of the neighboring section centered on the position of the measurement value D (Pi) is defined. In FIG. 11, a neighboring section having a width of “2j + 1” is defined. When such a width is defined, as shown in the figure, a total of (2j + 1) pieces from the (i−j) th measurement value D (Pi−j) to the (i + j) th measurement value D (Pi + j). The measured value is the measured value in the neighborhood section. Therefore, a simple average value Av (D (Pi−j) to D (Pi + j)) of the measurement values in these neighboring sections is obtained by calculation, and this is used as a new measurement value DD (Pi) after the smoothing process. .

  If the same process is performed for all the measurement values on the same measurement line, the first smoothing process in the first smoothing processing unit 172 for the measurement line is completed. When there are a plurality of measurement lines, the same smoothing process may be executed for each measurement line. For measurement values located near both left and right ends, a neighboring section having a width of “2j + 1” cannot be defined, but in that case, a neighboring section having as much width as possible may be defined. . For example, for the first measurement value D (P1), a total of (j + 1) measurement values from itself to the (1 + j) th measurement value D (P1 + j) are used as the measurement values in the neighboring section. The average value Av (D (P1) to D (P1 + j)) may be obtained by calculation and used as a new measured value DD (P1) after the smoothing process.

  In performing the smoothing process, instead of using the simple average value as described above, a weighted average value for obtaining an average after multiplying each measured value by a predetermined weight coefficient may be used. It doesn't matter. For example, FIG. 12 is a graph showing an example of a weight coefficient distribution used for obtaining such a weighted average value. This graph shows an example in which the distribution of weighting coefficients is Gaussian. The horizontal axis corresponds to the arrangement position of the individual measurement values, and the vertical axis represents the weighting factor by which the individual measurement values are multiplied. For example, the measurement value D (Pi) at the position Pi is multiplied by the largest coefficient ki, and the measurement value D (Pi−j) at the position Pi−j and the measurement value D (Pi + j) at the position Pi + j are the smallest. The coefficients ki−j and ki + j are multiplied.

  As described above, by performing the averaging process by the first smoothing processing unit 172, finally, the measurement points P1, P2, P3,..., Pi-1, Pi, Pi + 1,. Measured values DD (P1), DD (P2), DD (P3),..., DD (Pi-1), DD (Pi), DD (Pi + 1),. Pn) is obtained.

  The coating film forming unit 173 controls the die moving unit 160 according to the distance measurement values DD (P1), DD (P2), DD (P3),... Smoothed by the first smoothing processing unit 172. While the die 140 is moved up and down, the scanning unit 130 performs scanning (in the case of the example in FIG. 1, the stage 120 is gradually moved in the X-axis direction), and the fluid film material is discharged from the die 140 into a sheet shape. In this state, the coating film M3 is formed by applying the sheet-like film M2 on the upper surface of the substrate S. The manner in which the coating film M3 is formed is as shown in the side sectional view of FIG.

  The coating film measurement unit 174 performs processing for taking in a distance measurement value to the upper surface of the coating film M3 measured by the displacement meter 150 while causing the scanning unit 130 to perform scanning. For example, in the case of the example shown in FIG. 6, the measurement values D (Q1) and D (Q2) are the measurement values for the measurement points P1, P2, P3,..., Pi-1, Pi, Pi + 1,. , D (Q3), ..., D (Qi-1), D (Qi), D (Qi + 1), ..., D (Qn).

  The scanning for forming the coating film by the coating film forming unit 173 and the scanning for measuring the distance to the upper surface of the coating film by the coating film measuring unit 174 can be performed independently of each other. 6, if the displacement meters 151 to 153 are arranged on the left side (side toward the scanning direction) rather than the die 140, the coating film forming operation by the coating film forming unit 173 and the coating are performed. It is efficient because the distance measuring operation by the film measuring unit 174 can be performed simultaneously by the same moving operation. In practical use, the coating film forming unit 173 and the coating film measuring unit 174 cooperate with each other to cause the scanning unit 130 to perform scanning so that the coating film forming unit 173 forms the coating film and the coating film measuring unit 174. It is preferable that the measurement by is performed simultaneously by one scanning.

  The second smoothing processing unit 175 performs a second smoothing process for spatially smoothing the distance measurement value at each position along the predetermined measurement line taken in by the coating film measuring unit 174. carry out. In the second smoothing process, in the same manner as the first smoothing process described above, the measured values at the individual measurement points along the measurement line are included in the neighboring section having a predetermined width centered on the point. Can be executed by replacing the average value of the measurement values at a plurality of measurement points included in As a result, the measured values DD (Q1), DD (Q2), DD (Q3), ..., DD (Qi-1), DD (Qi), DD (Qi + 1), ..., DD (Qn) after the smoothing process. Will be obtained.

  However, in the first smoothing process executed by the first smoothing processing unit 172 and the second smoothing process executed by the second smoothing processing unit 175, the degree of smoothing is separately set. It is set so that optimum smoothing is performed according to the characteristics of the material constituting the substrate S and the characteristics of the material constituting the coating film M3. Specifically, if smoothing is performed by the method shown in FIG. 11, the width of the neighboring section defined by the first smoothing process, the width of the neighboring section defined by the second smoothing process, Can be set independently, and smoothing processing using different neighboring section widths is performed. In other words, the size of the smoothing filter used in the first smoothing process and the size of the smoothing filter used in the second smoothing process can be changed.

  For example, as shown in FIG. 8, if the layer 15 to be a rib layer is formed as a coating film on the upper surface of a dielectric layer 11 made of a glass paste containing a pigment, What is necessary is just to make it set the degree of smoothing in the base-material measurement step which measures the height of the upper surface of the layer 11 high. If it does so, the fine thickness fluctuation | variation by the unevenness | corrugation of the surface of the dielectric material layer 11 will be excluded, and the dispersion | variation which arises according to the distribution depth of a pigment will also be averaged. In other words, by performing a smoothing process using a relatively large size smoothing filter, a process of cutting high-frequency components of fluctuation is performed. On the other hand, if the degree of smoothing in the coating film measurement stage for measuring the height of the upper surface of the layer 15 is set low, a sudden film thickness variation occurs at the end 15T of the layer 15 as shown in FIG. Even in such a case, it is possible to prevent such film thickness fluctuations from being lost by smoothing, and to detect them appropriately. In other words, by performing a smoothing process using a smoothing filter having a relatively small size, a process for leaving a high-frequency component of fluctuation is performed. In the case of this example, the width of the neighboring section defined by the first smoothing process (the size of the smoothing filter) is eventually determined from the width of the neighboring section defined by the second smoothing process (the size of the smoothing filter). Can be set larger.

  For example, as shown in FIG. 11, when the neighborhood section is defined by an expression of width = 2j + 1, in the first smoothing process, j = 250 is set, and the measurement values distributed over a relatively wide range of 501 in total. In the second smoothing process, j = 2 may be set, and smoothing may be performed to obtain the average of the measured values distributed in a relatively narrow range of a total of five. . Then, the fluctuation component based on the unevenness of the surface of the dielectric layer 11 and the distribution depth of the pigment is removed by smoothing, but the sudden film thickness fluctuation generated at the end 15T of the layer 15 remains as it is. . Of course, in the second smoothing process, j = 0 may be set so that substantially no smoothing is performed. Thus, in the present invention, “the degree of smoothing” is used to mean “the lowest degree of smoothing” when no smoothing is performed. The meaning of “smoothing” is synonymous with “no smoothing”.

  The film thickness calculation unit 176 is based on the difference between the distance measurement value after the smoothing processing by the first smoothing processing unit 172 and the distance measurement value after the smoothing processing by the second smoothing processing unit 175. The calculation for obtaining the thickness of the coating film M3 at each position along each measurement line is performed. As described above with reference to FIG. 6, the film thickness value of each part is obtained by such calculation. If necessary, some of the determined film thickness values for representative locations may be displayed on the display screen.

  The above is the operation of coating film formation and film thickness measurement in the coating film forming apparatus shown in FIG. 10. This apparatus uses the results of film thickness measurement to call a defect determination stage and an end shape presentation stage. A function for performing additional processing is provided.

  The defect determination unit 177 calculates a deviation between the reference film thickness set in advance and the film thickness obtained by the film thickness calculation unit 176, and when the obtained deviation exceeds a predetermined threshold value, It is a component that performs a defect determination step of determining a film as defective. If the reference film thickness and threshold value are set in advance, if the difference between the film thickness value obtained by the film thickness calculation unit 176 and the reference film thickness exceeds the threshold value, a coating film is formed. Since it can be immediately determined that the lot is defective, the lot can be removed from the production line on the spot. When focusing on the film thickness variation at the end 15T as shown in FIG. 9, the maximum value of the film thickness of the portion included within a predetermined distance from the coating start end or the coating end end or A minimum value may be obtained, and pass / fail judgment may be made based on whether the maximum value or the difference between the minimum value and the reference film thickness exceeds a threshold value.

  On the other hand, the end shape presentation unit 178 creates an image showing the cross-sectional shape of one or both of the coating start end and the coating end end of the coating film M3 based on the film thickness obtained by the film thickness calculation unit 176. And it is a component which performs the edge part presentation stage which presents this. The end shape presentation unit 178 can create, for example, an image as shown in FIG. 9 and present it on the display screen. If an image showing the cross-sectional shape of the end portion 15T is presented, the operator can recognize the state of the end portion 15T while viewing the image, and can make a good / bad determination based on human judgment.

  FIG. 13 is a flowchart for explaining the operation procedure of the coating film forming apparatus shown in FIG. First, in step S <b> 1 corresponding to the preparation stage, a step of placing and fixing the base material S on the stage 120 and preparing the fluid film material M <b> 1 on the die 140 is performed. Subsequent steps S2 and S3 are procedures for measuring the base material. First, in step S2, the first scan is performed, and the distance measurement values D (P1), D (P2),..., D (Pn) indicating the height of the upper surface of the substrate S are the substrate measurement unit 171. Is taken in. In step S3, the first smoothing process is performed on the measurement values taken into the base material measurement unit 171, and the measurement values DD (P1), DD (P2),. DD (Pn) is obtained by the first smoothing processing unit 172.

  The next steps S4 and S5 are procedures for the coating film measurement stage, but step S4 also serves as a procedure for the coating film formation stage. That is, in step S4, the function of the coating film forming unit 173 causes the die 140 according to the measured values DD (P1), DD (P2),..., DD (Pn) after the smoothing process obtained in step S3. The second scan is carried out while moving up and down. At this time, the sheet-like film M2 is discharged from the die 140, and the coating film M3 is formed on the substrate S. At the same time, distance measurement values D (Q1), D (Q2),..., D (Qn) indicating the height of the upper surface of the formed coating film M3 are taken into the coating film measurement unit 174. In step S5, the second smoothing process is performed on the measurement values taken into the coating film measurement unit 174, and the measurement values DD (Q1), DD (Q2),. DD (Qn) is obtained by the second smoothing processing unit 175. As already described, the level of smoothing performed by the second smoothing processing unit 175 can be set to be different from the level of smoothing performed by the first smoothing processing unit 172. Depending on the individual case, the optimum degree of smoothing is set.

  The subsequent step S6 is a film thickness calculation stage procedure, and the film thickness T (Pi) at the i-th location Pi is determined by the calculation T (Pi) = DD (Pi) −DD (Qi). The final step S7 is a procedure of a defect determination stage and an end shape presentation stage, and defect determination and end shape presentation processing are executed based on the film thickness value obtained in step S6.

It is a perspective view which shows the physical structure part of the coating film forming apparatus which concerns on basic embodiment of this invention. It is a sectional side view which shows the state which cut | disconnected the principal part of the apparatus shown in FIG. 1 along the measurement line L1. When the upper surface of the base material S is inclined, it is a sectional side view showing that the distance d between the discharge port of the die 140 and the upper surface of the base material S varies depending on the position. When the upper surface of the base material S is inclined, it is a sectional side view showing that the distance d between the discharge port and the upper surface of the base material S can be kept constant by moving the die 140 up and down. It is a sectional side view which shows the principle of the process of the base-material measurement step performed with the apparatus shown in FIG. It is a sectional side view which shows the principle of the process of the coating film measurement step performed with the apparatus shown in FIG. It is side sectional drawing which shows the structure of the back plate for general plasma display panels. It is a sectional side view which shows the state in the middle of the manufacturing process of the backplate shown in FIG. FIG. 9 is an enlarged side cross-sectional view showing the shape of the end portion of the formed resin layer in the intermediate stage component shown in FIG. 8. It is a block diagram showing the whole composition of the coating film forming device concerning one embodiment of the present invention. It is a figure which shows a specific example of the smoothing process implemented in this invention. 12 is a graph illustrating an example of a weight coefficient distribution used in the smoothing process illustrated in FIG. 11. It is a flowchart explaining the operation | movement procedure of the coating film forming apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Glass layer 11 ... Dielectric layer 12 which consists of glass paste containing a pigment ... Electrode 13 ... Rib layer 14 ... Phosphor layer 15 ... Layer which has glass paste as a main component (coating film)
15T ... layer end portion 100 ... pedestal plate 110 ... support member 111, 112 ... side wall portion 113 ... bridge support member 120 ... stage 130 ... scanning means 131, 132 ... transport rail 133 ... slider 140 ... die 150 ... displacement meter 151 153 ... Displacement meter 160 ... Die moving means 170 ... Control means 171 ... Substrate measuring section 172 ... First smoothing processing section 173 ... Coating film forming section 174 ... Coating film measuring section 175 ... Second smoothing processing section 176 ... Film thickness calculation part 177 ... Defect determination part 178 ... End shape presentation part D ... Measurement distance DD by displacement meter ... Measurement value d after smoothing process ... Gap interval k ... Weighting factors L1 to L3 ... Measurement line M1 ... Flowable film material M2 ... sheet-like film M3 ... coating films P1 to Pn ... locations Q1 to Qn on measurement line L1 ... locations on coating film M3 ... base materials S1 to S7 ... each step V1, flow chart Level X indicating the position of the discharge opening of 2 ... die 140, Y, the coordinate axis of the Z ... three-dimensional coordinate system

Claims (12)

A method of forming a coating film on a substrate by discharging a sheet-like film from a die,
A stage of fixing a substrate on a stage and arranging a die having a function of discharging a fluid film material in a sheet shape above the substrate;
A base material measuring step of measuring the height on the measurement line along the moving direction of the upper surface of the base material while moving the base material or the die along a predetermined moving direction;
While the die is moved up and down according to the height measured in the base material measurement step, the base material or the die is moved in the moving direction while the fluid film material is discharged from the die into a sheet shape. A coating film forming step of applying a sheet-like film on the upper surface of the base material to form a coating film by moving along the substrate;
A coating film measuring step of measuring the height of the upper surface of the coating film on the measurement line while moving the substrate or the die along the moving direction;
A film that performs an operation for calculating the film thickness of the coating film in each part along the measurement line based on the difference between the height measurement value in the base material measurement stage and the height measurement value in the coating film measurement stage Thickness calculation stage,
Have
In the substrate measurement step and the coating film measurement step, a smoothing process for spatially smoothing the obtained measurement values is performed, and the degree of smoothing is determined as the substrate measurement step. A method for forming a coating film, wherein the coating film measurement step is set so as to be different. In the coating film formation method of Claim 1,
A coating film forming method, wherein the coating film forming stage and the coating film measuring stage are simultaneously performed by the same movement operation. In the coating film formation method of Claim 1 or 2,
Replacing the measurement values at individual measurement points along the measurement line with simple averages or weighted average values of measurement values at multiple measurement points included in a neighboring section with a predetermined width centered on the relevant point The coating film forming method is characterized in that the smoothing process is executed by the step, and the width of the neighboring section is set to be different between the smoothing process in the base material measurement stage and the smoothing process in the coating film measurement stage. In the coating film formation method in any one of Claims 1-3,
The computer calculates the deviation between the preset reference film thickness and the film thickness obtained in the film thickness calculation stage, and if the obtained deviation exceeds a predetermined threshold value, the formed coating film is regarded as defective. A coating film forming method, further comprising a defect determination step of executing a determination process. In the coating film formation method in any one of Claims 1-4,
Based on the film thickness obtained in the film thickness calculation stage , an image showing the cross-sectional shape of one or both of the coating start end and the coating end end of the coating film is created on the computer, and processing for presenting it is executed. The method for forming a coating film further comprises the step of presenting an end shape. In the coating film formation method in any one of Claims 1-5,
For a back panel of a plasma display panel having a two-layer structure of a glass layer as a base and a dielectric layer made of a glass paste containing a pigment, and electrodes are embedded at predetermined positions in the dielectric layer A substrate is fixed on a stage as a base material, and a layer mainly composed of a glass paste to be a rib layer is formed on the upper surface of the dielectric layer as a coating film,
Coating film formation characterized in that smoothing in the smoothing process in the base material measurement stage is set to have a higher degree of smoothing than in the smoothing process in the coating film measurement stage Method. An apparatus for forming a coating film on a substrate by discharging a sheet-like film from a die,
A stage for fixing the substrate;
A support provided above the stage;
A die attached to the support so as to be movable in the vertical direction, and having a function of discharging a fluid film material into a sheet,
Die moving means for moving the die up and down with respect to the support;
A displacement meter attached to the support and measuring a distance to an object placed on the stage;
Scanning means for scanning the die and the displacement meter with respect to the substrate on the stage by moving the stage or the support along a predetermined movement direction;
Control means for controlling the scanning means, the die, the die moving means, and taking in the measured value of the displacement meter;
The control means comprises
A base material measuring unit that captures a distance measurement value to the top surface of the base material measured by the displacement meter while causing the scanning unit to perform scanning;
A first smoothing processing unit for performing a first smoothing process for spatially smoothing a distance measurement value at each position along a predetermined measurement line captured by the base material measurement unit;
The die moving unit is controlled according to the distance measurement value smoothed by the first smoothing processing unit to cause the scanning unit to perform scanning while moving the die up and down, and from the die to the fluid film In a state where the material is discharged in the form of a sheet, a coating film forming unit that forms a coating film by applying a sheet-like film on the upper surface of the substrate;
A coating film measuring unit that captures a distance measurement value to the upper surface of the coating film measured by the displacement meter while causing the scanning unit to perform scanning;
A second smoothing processing unit for performing a second smoothing process for spatially smoothing a distance measurement value at each position along the measurement line captured by the coating film measuring unit;
Based on the difference between the distance measurement value after the smoothing processing by the first smoothing processing unit and the distance measurement value after the smoothing processing by the second smoothing processing unit, along the measurement line A film thickness calculator for calculating the thickness of the coating film at each position;
The coating film forming apparatus is characterized in that the degree of smoothing in the first smoothing process and the second smoothing process can be set separately. In the coating film forming apparatus according to claim 7,
The coating film forming unit and the coating film measuring unit cooperate to cause the scanning unit to perform scanning, and the coating film forming unit by the coating film forming unit and the measurement by the coating film measuring unit are simultaneously performed by one scanning. A coating film forming apparatus characterized in that it is configured as described above. The coating film forming apparatus according to claim 7 or 8,
Replacing the measurement values at individual measurement points along the measurement line with simple averages or weighted average values of measurement values at multiple measurement points included in a neighboring section with a predetermined width centered on the relevant point The coating film forming apparatus is characterized in that the smoothing process is executed by the first smoothing process and the second smoothing process so that the width of the neighboring section can be set differently. In the coating film formation apparatus in any one of Claims 7-9,
A defect that determines the deviation between the preset reference film thickness and the film thickness calculated by the film thickness calculator, and determines that the formed coating film is defective when the calculated deviation exceeds a predetermined threshold value. A coating film forming apparatus, further comprising a determination unit in the control means. In the coating film formation apparatus in any one of Claims 7-10,
Based on the film thickness obtained by the film thickness calculation unit, an image showing the cross-sectional shape of one or both of the coating start end and the coating end end of the coating film is created, and an end shape presenting unit for presenting this is shown. A coating film forming apparatus further provided in the control means.   The program for functioning a computer as a control means in the coating film forming apparatus in any one of Claims 7-11, or the computer-readable recording medium which recorded the said program.