JP2022138108A - Discharge pressure evaluation method, discharge pressure evaluation program, recording medium and substrate processing apparatus - Google Patents

Abstract

To evaluate a discharge pressure imparted to process liquid for discharging the process liquid from a nozzle in a rational time according to propriety of the discharge pressure.SOLUTION: There are provided N pieces of first to N-th evaluation stages for evaluating a discharge pressure with mutually different evaluation items. When it is determined that the discharge pressure is proper in evaluation with an evaluation item according to an I-th evaluation stage, evaluation of the discharge pressure with the evaluation item according to (I+1)-th evaluation stage is executed, on the other hand, when it is determined that the discharge pressure is improper in the evaluation with the evaluation item according to the I-th evaluation stage, evaluation of the discharge pressure with evaluation stages subsequent to the I-th evaluation stage is not executed (in other words, the evaluation is omitted).SELECTED DRAWING: Figure 21

Description

The present invention relates to a technique for ejecting a treatment liquid from a nozzle by applying ejection pressure to the treatment liquid. Examples of objects onto which the treatment liquid is discharged from the nozzles include semiconductor substrates, photomask substrates, liquid crystal display substrates, organic EL display substrates, plasma display substrates, FED (Field Emission Display) substrates, and optical disk substrates. Substrates, substrates for magnetic disks, substrates for magneto-optical disks, etc. are included.

As disclosed in Patent Documents 1 and 2, when a processing liquid ejected from a nozzle is applied to a substrate, the ejection pressure applied to the processing liquid greatly affects the thickness of the processing liquid applied to the substrate. Therefore, in Patent Document 1, the waveform of the discharge pressure is divided into a plurality of sections, and whether or not the discharge pressure is within the allowable range is evaluated based on the gradient of the waveform in each section. Further, in Japanese Patent Laid-Open No. 2002-200010, optimization of parameters related to the discharge pressure is attempted for each region such as the rising region and the steady discharge region.

JP 2011-005465 A Japanese Patent Application Laid-Open No. 2020-040046

That is, in Patent Documents 1 and 2, by evaluating the waveform of the discharge pressure in each of a plurality of sections or regions, the discharge pressure can be evaluated with high accuracy. On the other hand, evaluating such a large number of evaluation items causes an increase in the time required to evaluate the discharge pressure. In particular, it was not always rational to evaluate all evaluation items over a long period of time with respect to an inappropriate discharge pressure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is possible to evaluate the ejection pressure applied to the processing liquid for ejecting the processing liquid from the nozzle in a reasonable time according to the appropriateness of the ejection pressure. intended to

The ejection pressure evaluation method according to the present invention evaluates the ejection pressure of an ejection device that applies an ejection pressure to a treatment liquid and ejects the treatment liquid from a nozzle using different evaluation items. is an integer of 2 or more) evaluation stage, a step of evaluating the discharge pressure by the evaluation item related to the first evaluation stage, and the I-th (I is an integer of 1 or more and less than N ), when the discharge pressure is determined to be appropriate in the evaluation by the evaluation items related to the evaluation stage of (I+1), the discharge pressure is evaluated by the evaluation items related to the (I+1)th evaluation stage, while the I-th evaluation stage is performed. and a step of not performing the evaluation of the discharge pressure in the subsequent evaluation stages after the I-th evaluation stage when the discharge pressure is determined to be inappropriate in the evaluation of the evaluation item.

The ejection pressure evaluation program according to the present invention evaluates the ejection pressure of an ejection device that applies an ejection pressure to a treatment liquid and ejects the treatment liquid from a nozzle using different evaluation items. is an integer of 2 or more) evaluation stage, a step of evaluating the discharge pressure by the evaluation item related to the first evaluation stage, and the I-th (I is an integer of 1 or more and less than N ), when the discharge pressure is determined to be appropriate in the evaluation by the evaluation items related to the evaluation stage of (I+1), the discharge pressure is evaluated by the evaluation items related to the (I+1)th evaluation stage, while the I-th evaluation stage is performed. If the discharge pressure is determined to be inappropriate in the evaluation by the evaluation items, the computer is caused to execute a step of not executing the evaluation of the discharge pressure in the evaluation stages after the I-th evaluation stage.

A recording medium according to the present invention records the ejection pressure evaluation program described above so that it can be read by a computer.

A substrate processing apparatus according to the present invention includes a nozzle, a pressure applying unit that applies a discharge pressure to a processing liquid to discharge the processing liquid to the nozzle, a measurement unit that measures the discharge pressure, and a nozzle that applies the discharge pressure to the processing liquid. a control unit that stores execution details in N evaluation stages from the first to Nth (N is an integer equal to or greater than 2) for evaluating the ejection pressure in the ejection device that ejects the treatment liquid from each other with mutually different evaluation items; , the control unit evaluates the discharge pressure by the evaluation item related to the first evaluation stage among the N evaluation stages, and the I-th (I is 1 or more and less than N) among the N evaluation stages If the discharge pressure is determined to be appropriate in the evaluation by the evaluation items related to the evaluation stage of (integer), the discharge pressure is evaluated by the evaluation items related to the (I+1)th evaluation stage. If the discharge pressure is determined to be inappropriate in the evaluation of the evaluation item, the evaluation of the discharge pressure is not performed in the subsequent evaluation stages after the I-th evaluation stage.

In the present invention (ejection pressure evaluation method, ejection pressure evaluation program, recording medium, and substrate processing apparatus) configured as described above, N evaluations from the first to the Nth are performed to evaluate the ejection pressure using different evaluation items. A stage is provided and the evaluation stages from 1 to N can be performed in sequence. However, when the discharge pressure is determined to be appropriate in the evaluation by the evaluation items related to the I-th evaluation stage, the discharge pressure is evaluated by the evaluation items related to the (I+1)th evaluation stage. If the discharge pressure is determined to be inappropriate in the evaluation by the evaluation item related to the evaluation stage, the evaluation of the discharge pressure in the evaluation stages after the I-th evaluation stage is not executed. In other words, when the ejection pressure is evaluated in order by the 1st to Nth evaluation stages, if the ejection pressure is determined to be inappropriate in any of the evaluation stages, the subsequent evaluation stages are not evaluated. As a result, it is possible to evaluate the ejection pressure applied to the treatment liquid for ejecting the treatment liquid from the nozzles in a reasonable amount of time according to the appropriateness of the ejection pressure.

Further, the discharge pressure evaluation method may be configured such that different evaluation values are given to the discharge pressure according to the difference in the number of evaluation steps in which the discharge pressure is evaluated among the N evaluation steps. With such a configuration, a discharge pressure with a greater number of evaluation stages executed can be given a better evaluation value, and an appropriate evaluation value can be given to the discharge pressure according to the appropriateness of the discharge pressure.

In addition, during the evaluation target period including at least the main period from when the treatment liquid is started to be discharged from the nozzle to when the discharge pressure rises to a predetermined pressure and when the discharge pressure starts to decrease from the predetermined pressure, the discharge pressure is A step of extracting a feature amount of the time change of the ejection pressure over the entire evaluation target period as an overall feature amount based on the measurement result, and a step of evaluating the time change of the ejection pressure based on the overall feature amount. , the discharge pressure evaluation method may be configured so that the first evaluation stage has an evaluation item for evaluating the discharge pressure. In such a configuration, measurement is performed during an evaluation period that includes at least a major period from when the treatment liquid is started to be discharged from the nozzle to when the discharge pressure rises to a predetermined pressure and when the discharge pressure starts to decrease from the predetermined pressure. Based on the measured value of the ejection pressure, the characteristic amount of the temporal change of the ejection pressure in the entire evaluation target period is extracted as the overall characteristic amount, and the temporal change of the ejection pressure is evaluated based on the overall characteristic amount. This makes it possible to reflect in the evaluation of the ejection pressure whether or not the ejection pressure is appropriate for the entire period that affects the thickness of the treatment liquid applied to the substrate (in other words, the evaluation target period).

The evaluation target period is the main period, and the ejection pressure evaluation method is configured so that the main feature amount, which is the feature amount of the temporal change in the ejection pressure in the entire main period, is extracted as the overall feature amount. good too. With such a configuration, when the main period has a particularly large effect on the thickness of the treatment liquid applied to the substrate (in other words, when the period after the main period has a small effect), It is possible to reflect the suitability of the discharge pressure in the evaluation of the discharge pressure.

In addition, the main feature amount constitutes the discharge pressure evaluation method so as to indicate the difference between the main approximate waveform that approximates the time change of the discharge pressure over the entire main period and the time change of the discharge pressure over the main period. may With such a configuration, it is possible to appropriately evaluate the ejection pressure during the entire main period based on the approximate waveform for the time change of the ejection pressure during the entire main period.

In addition, the main approximation waveform is a linear approximation of the time change in the ejection pressure that increases with the passage of time after the start of ejection of the treatment liquid from the nozzle. a rising approximate straight line that increases linearly with increasing pressure, a starting time approximate straight line indicating the discharge start pressure provided between the start point of ejection of the treatment liquid from the nozzle and the rising approximate straight line, and the rising approximate straight line reaching a steady pressure. The discharge pressure evaluation method may be configured so as to have a steady straight line that indicates the steady pressure provided from the beginning to the end of the main period. With such a configuration, it is possible to approximate the time change of the discharge pressure over the entire main period and appropriately evaluate the discharge pressure over the entire period.

The evaluation target period is the first period from the start of ejection of the treatment liquid from the nozzles to the end of ejection of the treatment liquid from the nozzles. The ejection pressure evaluation method may be configured such that the first feature amount, which is the feature amount, is extracted as the overall feature amount. With such a configuration, the ejection pressure affects the thickness of the treatment liquid applied to the substrate throughout the first period from the start of ejection of the treatment liquid from the nozzle to the end of ejection of the treatment liquid from the nozzle. In addition, it is possible to reflect the appropriateness of the discharge pressure in the entire first period in the evaluation of the discharge pressure.

Further, the first feature value is the discharge pressure evaluation value so as to indicate the difference between the first approximate waveform that approximates the time change of the discharge pressure over the entire first period and the time change of the discharge pressure over the first period. A method may be configured. With such a configuration, it is possible to appropriately evaluate the ejection pressure over the entire period from the start to the end of ejection of the treatment liquid from the nozzles, based on the approximate waveform of the change in the ejection pressure over time.

The first approximation waveform is obtained by linearly approximating the change in the ejection pressure that increases with the passage of time after the ejection of the treatment liquid from the nozzle is started, from the ejection start pressure to the steady pressure higher than the ejection start pressure. A rise approximation line that increases linearly with the passage of time, a start time approximation line indicating the discharge start pressure provided between the start point of discharge of the processing liquid from the nozzle and the rise approximation line, and a process from the nozzle. By linearly approximating the time change of the discharge pressure that decreases with the passage of time before the end of the liquid discharge, the fall approximation that linearly decreases with the passage of time from the steady pressure to the discharge end pressure that is smaller than the steady pressure. A straight line, an approximation at the end of the ejection end pressure provided between the approximation falling line and the end point of ejection of the processing liquid from the nozzle, and the approximation at the rise and the approximation at the fall are connected to each other. Then, the discharge pressure evaluation method may be configured so as to have a steady straight line indicating the steady pressure. With such a configuration, the change in the ejection pressure over time from the start to the end of ejection of the treatment liquid from the nozzles can be approximated by a trapezoidal waveform, and the ejection pressure in the entire period can be appropriately evaluated.

a step of extracting, as a second feature amount, a characteristic amount of a temporal change in the discharge pressure in a second period shorter than the evaluation period; and evaluating the temporal change in the discharge pressure based on the second characteristic amount. The discharge pressure evaluation method may be configured such that the second evaluation stage of the N evaluation stages has an evaluation item of evaluating the discharge pressure by performing the steps of: With such a configuration, the ejection pressure can be evaluated with high accuracy based on the temporal change in the ejection pressure during a period shorter than the entire period from the start to the end of ejection of the treatment liquid from the nozzles.

Further, a predetermined rising initial period from the start of ejection of the treatment liquid from the nozzles is set as the second period. The discharge pressure evaluation method may be configured such that a feature quantity indicating the difference between the regression curve of the change and the time change of the discharge pressure in the initial rising period is extracted as the second feature quantity. With such a configuration, it is possible to evaluate the ejection pressure taking into consideration the time change in the ejection pressure immediately after the treatment liquid starts to flow from the nozzles.

Further, the ejection pressure evaluation method may be configured such that the rising period from the start of ejection of the treatment liquid from the nozzle until the ejection pressure increases to a predetermined pressure is set as the second period. With such a configuration, the ejection pressure can be evaluated in consideration of the time change of the ejection pressure during the rising period.

Specifically, the ejection pressure evaluation method may be configured such that the length of the rising period is extracted as the second feature amount. With such a configuration, the discharge pressure can be evaluated in consideration of the rising speed of the discharge pressure.

Further, the ejection pressure evaluation method may be configured such that the number of times the one-time differentiation of the ejection pressure change with time intersects a predetermined threshold value during the rising period is extracted as the second feature amount. With such a configuration, the ejection pressure can be evaluated in consideration of the smoothness of the time change of the ejection pressure during the rising period.

Further, the ejection pressure evaluation method may be configured such that the number of times the absolute value of the second derivative of the time variation of the ejection pressure intersects a predetermined threshold value during the rising period is extracted as the second feature amount. With such a configuration, the ejection pressure can be evaluated in consideration of the smoothness of the time change of the ejection pressure during the rising period.

Further, in the rise period, a time period during which the second derivative of the time change of the ejection pressure is greater than a predetermined positive threshold, and a predetermined negative value in which the second derivative of the time change of the ejection pressure has the same absolute value as the positive threshold value. The discharge pressure evaluation method may be configured such that the ratio of the time when the is smaller than the threshold of is extracted as the second feature amount. With such a configuration, the ejection pressure can be evaluated by taking into account the difference in the time change of the ejection pressure between the initial stage and the final stage of the rising period.

A predetermined final rise period until the discharge pressure increases to a predetermined pressure is set as the second period. is extracted as the second feature value, and the approximate waveform at the end of the rise linearly approximates the time change of the discharge pressure, which increases over time in a pressure range smaller than the predetermined pressure. The final rise approximation line that overlaps the approximation curve obtained by and linearly increases with time until the steady pressure, which is the average value of the time change of the discharge pressure in the steady period after the final rise period, and the final rise approximation The discharge pressure evaluation method may be configured to have an extended straight line indicating the steady pressure, which is extended from the straight line to the end of the rising final period. With such a configuration, it is possible to evaluate the discharge pressure taking into account the degree of stall of the discharge pressure at the end of the rising period.

Further, the initial vibration period from the time when the discharge pressure reaches the maximum value to the time when the second derivative of the time change of the discharge pressure crosses zero twice is set as the second period. and the average value of the ejection pressure in a predetermined steady period after the initial oscillation period, and the difference between the smaller one of the average values of the ejection pressure and the maximum value of the ejection pressure is extracted as the second feature amount. A pressure assessment method may be configured. With such a configuration, the discharge pressure can be evaluated in consideration of the overshoot of the discharge pressure.

A predetermined transition period from the time when the discharge pressure exceeds the predetermined pressure is set as the second period, and the difference in the discharge pressure during the transition period with respect to the average value of the discharge pressure during the predetermined steady period after the transition period is calculated. The ejection pressure evaluation method may be configured such that the indicated feature amount is extracted as the second feature amount. With such a configuration, it is possible to evaluate the discharge pressure in consideration of the stability of the discharge pressure after the discharge pressure reaches the predetermined pressure.

A constant pressure period from when the ejection pressure exceeds the predetermined pressure to when the ejection pressure starts to decrease toward the end of ejection of the treatment liquid from the nozzle is set as the second period. The ejection pressure evaluation method may be configured such that the feature quantity indicating the difference between the maximum value and the minimum value of the pressure is extracted as the second feature quantity. With such a configuration, the ejection pressure can be evaluated with consideration given to the stability of the ejection pressure during the constant pressure period of the ejection pressure.

Further, in the ejection pressure evaluation method in which N is 3 or more, a step of extracting, as a third feature amount, a characteristic amount of a temporal change in the ejection pressure in a third period shorter than the evaluation period among the evaluation period. , and evaluating the time change of the ejection pressure based on the third feature amount, so that the third evaluation stage of the N evaluation stages has an evaluation item for evaluating the ejection pressure. , may constitute a discharge pressure evaluation method. With such a configuration, the ejection pressure can be evaluated with high accuracy based on the temporal change in the ejection pressure during a period shorter than the entire period from the start to the end of ejection of the treatment liquid from the nozzles.

Further, a pressure increase period is set as a third period in which the ejection pressure increases with time from the lower reference value to the upper reference value larger than the lower reference value after the start of ejection of the treatment liquid from the nozzles. One measured value of the discharge pressure between the reference value and the upper reference value, by linear regression with respect to the change in discharge pressure over time in the interval between the lower reference value and the one measured value Root-mean-square error between the obtained approximation line and discharge pressure time change, and the approximation line obtained by linear regression against the time change of discharge pressure in the interval between one measured value and the upper reference value and discharge pressure time Find the one measurement value that minimizes the sum of the change and the root mean square error, and the slope of the straight line between the lower reference value and the one measurement value, and the difference between the one measurement value and the upper reference value The discharge pressure evaluation method may be configured such that the ratio of the slope of the straight line of is extracted as the third feature amount. With such a configuration, the ejection pressure can be evaluated in consideration of the linearity of the increase in the ejection pressure.

Further, a predetermined final rise period until the discharge pressure increases to a predetermined pressure is set as a third period, and a final rise approximate waveform that approximates the time change of the discharge pressure in the final rise period and the discharge pressure in the final rise period. is extracted as a third feature value, and the approximate waveform at the end of rising is a linear approximation of the time change of the discharge pressure, which increases over time in a pressure range smaller than the predetermined pressure. It overlaps with the approximated curve obtained by , and increases linearly up to a predetermined pressure with the passage of time. A pressure assessment method may be configured. With such a configuration, it is possible to evaluate the discharge pressure taking into account the degree of stall of the discharge pressure at the end of the rising period.

Further, the initial oscillation period from the time when the discharge pressure reaches the maximum value to the time when the second derivative of the time variation of the discharge pressure crosses zero twice is set as the third period. , the sum of the value obtained by subtracting the steady pressure, which is the average value of the discharge pressure in a predetermined steady period after the initial vibration period, and the value obtained by subtracting the minimum value of the discharge pressure in the initial vibration period from the steady pressure is the third The discharge pressure evaluation method may be configured so as to be extracted as a feature amount. With such a configuration, the discharge pressure can be evaluated in consideration of the overshoot of the discharge pressure.

As described above, according to the present invention, the ejection pressure applied to the processing liquid for ejecting the processing liquid from the nozzle can be evaluated in a reasonable amount of time according to the appropriateness of the ejection pressure.

FIG. 1 is a diagram schematically showing the overall configuration of a coating apparatus that is an embodiment of a substrate processing apparatus according to the present invention. FIG. 4 is a diagram showing the configuration of a coating liquid supply mechanism; FIG. 2 is a block diagram showing an example of the configuration of a control unit; FIG. 4 is a flowchart showing an example of a discharge pressure evaluation method executed based on a discharge pressure evaluation program; FIG. 4 is a diagram for explaining each period used for evaluating the discharge pressure; The figure which shows typically an example of the calculation which a pressure evaluation part performs with respect to the time change of discharge pressure. FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in ejection pressure based on the feature amount Fv1; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv2; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv3; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal changes in discharge pressure based on the feature amount Fv4; FIG. 10 is a diagram showing an example of temporal change in discharge pressure determined to be inappropriate by evaluation based on the feature quantity Fv4; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv5; FIG. 10 is a diagram showing an example of temporal changes in ejection pressure determined to be inappropriate by evaluation based on the feature quantity Fv5; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv6; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv7; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv8; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in ejection pressure based on the feature amount Fv9; FIG. 10 is a diagram for explaining evaluation items for evaluating temporal change in ejection pressure based on the feature amount Fv10; FIG. 11 is a diagram for explaining evaluation items for evaluating a change in ejection pressure over time based on a feature amount Fv11; FIG. 10 is a diagram for explaining evaluation items for evaluating a change in discharge pressure over time based on a feature amount Fv12; FIG. 10 is a diagram for explaining evaluation items for evaluating a change in discharge pressure over time based on a feature amount Fv13; FIG. 10 is a diagram for explaining evaluation items for evaluating a change in discharge pressure over time based on a feature amount Fv14; 4 is a flowchart showing details of measurement result evaluation; FIG. 22 is a diagram schematically showing an example of operations performed according to the flowchart of FIG. 21; FIG. 10 is a diagram for explaining each period used in a modified example of evaluation items of discharge pressure; FIG. 11 is a diagram for explaining a modification of evaluation items for evaluating temporal change in discharge pressure based on feature quantity Fv1_1;

FIG. 1 is a diagram schematically showing the overall configuration of a coating apparatus, which is an embodiment of a substrate processing apparatus according to the present invention. This coating apparatus 1 is a slit coater that applies a coating liquid to the upper surface Sf of a substrate S that is conveyed horizontally from the left hand side to the right hand side in FIG. In the following figures, in order to clarify the arrangement relationship of each part of the apparatus, the transport direction of the substrate S is referred to as "X direction", and the horizontal direction from the left hand side to the right hand side in FIG. 1 is referred to as "+X direction". , the opposite direction is called the “−X direction”. In addition, in the horizontal direction Y perpendicular to the X direction, the front side of the apparatus is referred to as "-Y direction" and the back side of the apparatus is referred to as "+Y direction". Furthermore, the upward direction and the downward direction in the vertical direction Z are referred to as "+Z direction" and "−Z direction", respectively.

In the coating apparatus 1, the input conveyor 100, the input transfer section 2, the floating stage section 3, the output transfer section 4, and the output conveyor 110 are arranged close to each other in this order along the transport direction Dt (+X direction) of the substrate S. As will be described in detail below, these form a transport path for the substrate S extending in a substantially horizontal direction. In the following description, when the positional relationship is shown in relation to the transport direction Dt of the substrate S, "upstream side in the transport direction Dt of the substrate S" is simply referred to as "upstream side" and "downstream in the transport direction Dt of the substrate S". side" may be abbreviated simply as "downstream side". In this example, the (-X) side corresponds to the "upstream side" and the (+X) side corresponds to the "downstream side" relative to a certain reference position.

A substrate S to be processed is carried into the input conveyor 100 from the left hand side of FIG. The input conveyor 100 includes a roller conveyor 101 and a rotation drive mechanism 102 that rotates the roller conveyor 101. By rotating the roller conveyor 101, the substrate S is conveyed horizontally in the downstream direction, that is, in the (+X) direction. The input transfer section 2 includes a roller conveyor 21 and a rotation/elevation drive mechanism 22 having a function of rotating and elevating the roller conveyor 21 . As the roller conveyor 21 rotates, the substrate S is further transported in the (+X) direction. Further, the position of the substrate S in the vertical direction Z is changed as the roller conveyor 21 moves up and down. The substrate S is transferred from the input conveyor 100 to the levitation stage section 3 by the input transfer section 2 configured as described above.

The levitation stage unit 3 includes a flat stage divided into three along the substrate transport direction Dt. That is, the levitation stage section 3 has an entrance levitation stage 31, a coating stage 32 and an exit levitation stage 33, and the upper surfaces of these stages form part of the same plane. Further, the levitation stage section 3 has a lift pin drive mechanism 34 , a levitation control mechanism 35 and an elevation drive mechanism 36 . The lift pin driving mechanism 34 can raise and lower the lift pins provided on the entrance lifting stage 31 . The levitation control mechanism 35 can supply compressed air for levitating the substrate S to each stage of the levitation stage section 3 . The elevation driving mechanism 36 can raise and lower the exit floating stage 33 .

On the upper surface of each of the entrance levitation stage 31 and the exit levitation stage 33, a large number of ejection holes for ejecting compressed air supplied from the levitation control mechanism 35 are provided in a matrix. The substrate S floats. In this way, the substrate S is supported in a horizontal position with the lower surface Sb of the substrate S separated from the upper surface of the stage. The distance between the lower surface Sb of the substrate S and the upper surface of the stage, that is, the floating amount, can be, for example, 10 micrometers to 500 micrometers.

On the other hand, on the upper surface of the coating stage 32, ejection holes for ejecting compressed air and suction holes for sucking air between the lower surface Sb of the substrate S and the upper surface of the stage are alternately arranged. The distance between the lower surface Sb of the substrate S and the upper surface of the coating stage 32 is precisely controlled by the levitation control mechanism 35 controlling the amount of compressed air ejected from the ejection holes and the amount of suction from the suction holes. As a result, the position in the vertical direction Z of the upper surface Sf of the substrate S passing above the coating stage 32 is controlled to a specified value. As a specific configuration of the levitation stage section 3, for example, one described in Japanese Patent No. 5346643 can be applied. The amount of floating on the coating stage 32 is calculated by the control unit 9 based on the results of detection by sensors 61 and 62, which will be described in detail later, and can be adjusted with high precision by airflow control.

The substrate S carried into the levitation stage section 3 via the input transfer section 2 is given a propulsive force in the (+X) direction by the rotation of the roller conveyor 21 and conveyed onto the entrance levitation stage 31 . The entrance floating stage 31, coating stage 32, and exit floating stage 33 support the substrate S in a floating state, but do not have the function of moving the substrate S in the horizontal direction. The substrate S is transported in the levitation stage section 3 by the substrate transport section 5 arranged below the entrance levitation stage 31 , coating stage 32 and exit levitation stage 33 .

The substrate transfer unit 5 includes a chuck mechanism 51 that supports the substrate S from below by partially abutting on the peripheral portion of the lower surface of the substrate S, and a suction pad (not shown) provided on a suction member at the upper end of the chuck mechanism 51. A suction/travel control mechanism 52 having a function of applying a negative pressure to hold the substrate S by suction and a function of reciprocating the chuck mechanism 51 in the X direction is provided. When the chuck mechanism 51 holds the substrate S, the lower surface Sb of the substrate S is positioned higher than the upper surface of each stage of the floating stage section 3 . Therefore, the substrate S maintains its horizontal posture as a whole by the buoyancy applied from the levitation stage section 3 while the chuck mechanism 51 sucks and holds the peripheral portion. A thickness measuring sensor 61 is arranged near the roller conveyor 21 in order to detect the position of the upper surface of the substrate S in the vertical direction Z when the lower surface Sb of the substrate S is partially held by the chuck mechanism 51 . ing. A chuck (not shown) that does not hold the substrate S is positioned directly below the sensor 61, so that the sensor 61 can detect the upper surface of the attracting member, that is, the position of the attracting surface in the vertical direction Z. ing.

The chuck mechanism 51 holds the substrate S transported from the input transfer unit 2 to the levitation stage unit 3 . is transported to above the outlet floating stage 33 via above the coating stage 32 from the outlet. The transported substrate S is delivered to the output transfer section 4 arranged on the (+X) side of the exit floating stage 33 .

The output transfer section 4 includes a roller conveyor 41 and a rotation/elevation drive mechanism 42 having a function of rotating and elevating the roller conveyor 41 . As the roller conveyor 41 rotates, a driving force in the (+X) direction is applied to the substrate S, and the substrate S is further transported along the transport direction Dt. Further, the position of the substrate S in the vertical direction Z is changed as the roller conveyor 41 moves up and down. The substrate S is transferred from above the exit floating stage 33 to the output conveyor 110 by the output transfer section 4 .

The output conveyor 110 includes a roller conveyor 111 and a rotation driving mechanism 112 that rotates the conveyor. paid out to The input conveyor 100 and the output conveyor 110 may be provided as a part of the configuration of the coating device 1, or may be separate from the coating device 1. FIG. Further, for example, a substrate dispensing mechanism of another unit provided on the upstream side of the coating apparatus 1 may be used as the input conveyor 100 . Alternatively, a substrate receiving mechanism of another unit provided downstream of the coating apparatus 1 may be used as the output conveyor 110 .

A coating mechanism 7 for coating the upper surface Sf of the substrate S with a coating liquid is arranged on the transport path of the substrate S transported in this way. The coating mechanism 7 has a slit nozzle (hereinafter simply referred to as "nozzle") 71 having a slit-shaped ejection port. Although not shown, a positioning mechanism is connected to the nozzle 71, and the nozzle 71 is positioned above the application stage 32 by the positioning mechanism (the position indicated by the solid line in FIG. 1) or a position described later. Positioned in maintenance position. Further, a coating liquid supply mechanism 8 is connected to the nozzle 71 , the coating liquid is supplied from the coating liquid supply mechanism 8 , and the coating liquid is discharged from an ejection port that opens downward at the bottom of the nozzle.

FIG. 2 is a diagram showing the configuration of the coating liquid supply mechanism. As shown in FIG. 2, the coating liquid supply mechanism 8 uses a pump 81 as a feed source for feeding the coating liquid to the nozzle 71. The pump 81 feeds the coating liquid by volume change. As the pump 81, for example, a bellows type pump described in JP-A-10-61558 can be used. This pump 81 has a flexible tube 811 that can be elastically expanded and contracted in the radial direction. One end of this flexible tube 811 is connected to the application liquid replenishment unit 83 via a pipe 82 , and the other end is connected to the nozzle 71 via a pipe 84 .

A bellows 812 that is elastically deformable in the axial direction is arranged outside the flexible tube 811 . The bellows 812 has a small bellows portion 813 and a large bellows portion 814, and a pump chamber 815 between the flexible tube 811 and the bellows 812 contains an incompressible medium. A working disk portion 816 is provided between the small bellows portion 813 and the large bellows portion 814 . A driving portion 817 is connected to the operating disk portion 816 . When the driving portion 817 operates in response to a command from the control unit 9, the working disk portion 816 is axially displaced in a predetermined movement pattern (a pattern indicating changes in speed of the working disk portion 816 over time), and the bellows 812 change the volume inside the . As a result, the flexible tube 13 expands and contracts in the radial direction to perform a pumping operation, and feeds the coating liquid appropriately replenished from the coating liquid replenishing unit 83 toward the nozzle 71 . Therefore, the movement pattern of the working disk portion 816 is closely related to the ejection characteristics (change in ejection pressure over time) of the coating liquid ejected from the nozzles 71, and predetermined ejection characteristics can be obtained according to the movement pattern.

The coating liquid replenishment unit 83 has a storage tank 831 that stores the coating liquid. This storage tank 831 is connected to the pump 81 through a pipe 82 . An on-off valve 833 is inserted in the pipe 82 . The on-off valve 833 is opened in response to a replenishment command from the control unit 9 to allow the flexible tube 811 of the pump 81 to be replenished with the application liquid in the storage tank 831 . Conversely, it is closed in response to a replenishment stop command from the control unit 9 to restrict replenishment of the application liquid from the storage tank 831 to the flexible tube 811 of the pump 81 .

An on-off valve 85 is inserted in a pipe 84 connected to the output side of the pump 81 (left hand side in the figure), and is opened and closed according to an open/close command from the control unit 9 . As a result, it is possible to switch between feeding the coating liquid to the nozzle 71 and stopping the liquid feeding. A pressure gauge 86 is attached to the pipe 84 to detect the pressure (discharge pressure) of the coating liquid sent to the nozzle 71 and output the detection result (pressure value) to the control unit 9 .

As shown in FIG. 2, the nozzle 71 to which the coating liquid is supplied from the coating liquid supply mechanism 8 is provided with a flying height detection sensor 62 for detecting the flying height of the substrate S in a non-contact manner. is set up. With this sensor 62, it is possible to measure the separation distance between the floating substrate S and the upper surface of the stage surface of the coating stage 32, and the control unit 9 controls the positioning mechanism (not shown) according to the detected value. By doing so, the position where the nozzle 71 descends is adjusted. As the sensor 62, an optical sensor, an ultrasonic sensor, or the like can be used.

In order to perform predetermined maintenance on the nozzle 71, the coating mechanism 7 is provided with a nozzle cleaning standby unit 72, as shown in FIG. The nozzle cleaning standby unit 72 mainly has a roller 721, a cleaning section 722, a roller butt 723, and the like. Then, nozzle cleaning and liquid pool formation are carried out by these steps, and the ejection openings of the nozzles 71 are adjusted to a state suitable for the next coating process. In addition, the nozzle 71 is positioned at the position where the nozzle cleaning standby unit 72 is provided, that is, the maintenance position, and pseudo ejection is performed by ejecting the coating liquid from the nozzle 71 in order to evaluate the ejection pressure applied to the coating liquid.

Furthermore, the coating device 1 is provided with a control unit 9 (FIG. 3) for controlling the operation of each part of the device. FIG. 3 is a block diagram showing an example of the configuration of the control unit. As shown in FIG. 3 , the control unit 9 is a computer having a computing section 91 , a storage section 93 and a UI (User Interface) 95 . The calculation unit 91 is a processor configured by a CPU (Central Processing Unit) or the like, and by executing a discharge pressure evaluation program 97, a measurement execution unit 911 that executes measurement of the discharge pressure and an evaluation of the measured discharge pressure. A pressure evaluation unit 913 is constructed. The storage unit 93 is a storage device such as a HDD (Hard Disk Drive) or an SDD (Solid State Drive), and stores the above-described discharge pressure evaluation program 97 and the discharge pressure measurement measured when the discharge pressure evaluation program 97 is executed. store data 99; This ejection pressure evaluation program 97 is provided, for example, by a recording medium M provided separately from the control unit 9 . This recording medium M records an ejection pressure evaluation program 97 so that it can be read by a computer (control unit 9). Such a recording medium M includes, for example, a USB (Universal Serial Bus) memory, a memory card, or a storage device of an external server computer. In addition, the UI 95 has a display for displaying information to the user and an input device for receiving input operations by the user. As the control unit 9 having such a configuration, for example, various desktop, laptop, or tablet computers can be used.

FIG. 4 is a flow chart showing an example of a discharge pressure evaluation method executed based on a discharge pressure evaluation program. In step 101, the measurement execution unit 911 causes the application liquid to be ejected from the nozzles 71 by moving the operating disk unit 816 based on the movement pattern defined by the ejection pressure evaluation program 97 (pseudo ejection). As a result, when the working disk portion 816 is accelerated from zero speed to a predetermined target speed, it moves at a constant speed at the target speed, and then decelerates from the target speed to zero speed. However, as shown in Patent Document 2, the speed (parameter) of the working disk portion 816 is Adjusted and movement patterns are set.

Specifically, the discharge pressure is in the following order ・The discharge pressure increases from the initial pressure Pi to a target pressure Pt that is higher than the initial pressure Pi ・The discharge pressure stabilizes at the target pressure Pt ・The discharge pressure is reduced to the target pressure A movement pattern of the working disk portion 816 is defined in the discharge pressure evaluation program 97 so as to decrease from Pt to the initial pressure Pi.

Furthermore, in step S101, in parallel with the ejection of the coating liquid from the nozzles 71 accompanying the movement of the working disk portion 816, the measurement execution section 911 periodically measures the ejection pressure measured by the pressure gauge 86 at a predetermined sampling period. to get to. In this way, during the ejection period Tt (FIG. 5) during which the coating liquid is ejected from the nozzle 71, the measurement result of the ejection pressure applied to the coating liquid is acquired and stored in the storage unit 93 as the ejection pressure measurement data 99. . The discharge pressure measurement data 99 shows the time and the value of the discharge pressure measured at that time in association with each other.

In step S102, the pressure evaluation unit 913 evaluates the temporal change in the discharge pressure indicated by the discharge pressure measurement data 99 according to predetermined evaluation items. As will be described later, this evaluation item extracts a predetermined characteristic amount from the temporal change in the discharge pressure indicated by the discharge pressure measurement data 99, and evaluates the temporal change in the discharge pressure based on this characteristic amount. Next, each evaluation item for evaluating the time change of the discharge pressure indicated by the discharge pressure measurement data 99 will be described in detail.

FIG. 5 is a diagram for explaining each period used for evaluating the ejection pressure. In FIG. 5, the change in the discharge pressure over time is schematically shown in a graph in which the horizontal axis represents time and the vertical axis represents the discharge pressure. Note that the notation of such a graph is the same in each figure shown later. In the example of FIG. 5, the ejection pressure measurement data is obtained from before the ejection of the coating liquid from the nozzle 71 is started to after the ejection of the coating liquid from the nozzle 71 is finished (that is, before and after the ejection period Tt). 99 is obtained. In this example, the ejection pressure at the time ta when the ejection of the coating liquid from the nozzle 71 is started and the ejection pressure at the time te when the ejection of the coating liquid from the nozzle 71 is finished become the initial pressure Pi. there is However, the pressures at the start and end of ejection do not always match the initial pressure Pi.

As shown in FIG. 5, the ejection period Tt can be divided into four periods Ta, Tb, Tc, and Td. Details of the rising period Ta, the transition period Tb, the steady period Tc, and the falling period Td are as follows.

In the rising period Ta, the discharge pressure increases from the time ta when the coating liquid supply mechanism 8 starts discharging the coating liquid from the nozzle 71 (that is, the time ta when the coating liquid supply mechanism 8 starts moving the working disk portion 816). This is the period until the time tb when the target pressure Pt is reached. That is, when the ejection of the coating liquid from the nozzle 71 is started at time ta, the ejection pressure increases from the initial pressure Pi to the target pressure Pt from time ta to time tb.

The transition period Tb is a period from time tb to time tc when a predetermined vibration attenuation period elapses. This vibration damping period is a period required for the temporal change of the ejection pressure to stabilize, and is set by the user's input operation to the UI 95 and stored in the storage unit 93 .

The steady period Tc is from time tc to time td at which the coating liquid supply mechanism 8 starts reducing the discharge pressure (that is, time td at which the coating liquid supply mechanism 8 starts decelerating the operating disk portion 816 from the target speed). is the period of That is, the coating liquid supply mechanism 8 moves the working disk portion 816 at a constant speed from time tc to time td, and starts decelerating the working disk portion 816 at time td. Note that the discharge pressure basically stabilizes at the target pressure Pt during the steady period Tc. However, even during the steady period Tc, the time change of the discharge pressure includes minute vibrations, and the discharge pressure becomes higher or lower than the target pressure Pt.

Further, the constant pressure period Tbc is composed of the transition period Tb and the steady period Tc. That is, the constant pressure period Tbc is a period from time tb to time td.

The falling period Td is from time td to time te when the coating liquid supply mechanism 8 finishes discharging the coating liquid from the nozzle 71 (that is, time te when the coating liquid supply mechanism 8 stops the operation disk portion 816). period. That is, the ejection pressure decreases to the initial pressure Pi between time td and time te, and ejection of the coating liquid from the nozzle 71 stops at time te.

FIG. 6 is a diagram schematically showing an example of calculations executed by the pressure evaluation unit with respect to the time change of the discharge pressure. As shown in FIG. 6, the pressure evaluation unit 913 differentiates the time change of the discharge pressure with respect to time, thereby calculating a first derivative D1 of the time change of the discharge pressure. Further, the pressure evaluation unit 913 differentiates the first derivative D1 of the time change of the discharge pressure with respect to time, thereby calculating the second time derivative D2 of the time change of the discharge pressure. Further, the pressure evaluation unit 913 uses the following formulas: MAE (α, β)=(1/n)·(Σ|α−β|)
RMSE(α,β)=((1/n)·(Σ(α−β) ² )) ^1/2
Mean absolute error MAE and root mean square error RMSE are calculated based on n=number of data.

FIG. 7 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the feature amount Fv1. Evaluation items in FIG. absolute error), the time change of the discharge pressure indicated by the discharge pressure measurement data 99 is evaluated.

Specifically, linear regression analysis is performed on the change in discharge pressure over time between a predetermined lower reference pressure and a predetermined upper reference pressure that is greater than the lower reference pressure in the rising period Ta. , a rising regression line Lr_R is calculated. This rising regression line Lr_R linearly increases from the initial pressure Pi to the steady pressure Pm between time t11 and time t12.

Similarly, during the fall period Td, linear regression analysis is performed on the change in the discharge pressure over time between the upper reference pressure and the lower reference pressure to calculate the fall regression line Lr_F. This falling regression line Lr_F linearly decreases from the steady pressure Pm to the initial pressure Pi between time t13 and time t14.

The lower reference pressure and the upper reference pressure are higher than the initial pressure Pi and lower than the target pressure Pt. In this example, the lower reference pressure is a pressure obtained by adding 20% of the absolute value of the difference between the initial pressure Pi and the target pressure Pt to the initial pressure Pi, and the upper reference pressure is the initial pressure Pi and the target pressure Pt. This pressure is obtained by adding 80% of the absolute value of the difference from the pressure Pt to the initial pressure Pi.

In addition, a starting approximate straight line Lr_s is set for the section from time ta to time t11. The approximate straight line Lr_s at the start is a straight line with zero slope indicating the initial pressure Pi. In other words, the approximate straight line Lr_s at the start is a straight line that connects the start point of the ejection of the coating liquid from the nozzle 71 (time ta) to the start point of the rising regression line Lr_R. Depending on the state (inclination) of the regression line, the time t11 may come before the time ta, and the time t12 may come after the time tb. As a result, when t11<ta, the starting approximation line Lr_s is omitted.

In addition, an end time approximate straight line Lr_e is set for the section from time t14 to time te. This end time approximation line Lr_e is a straight line with a zero gradient indicating the initial pressure Pi. In other words, the end approximate straight line Lr_e is a straight line that connects the end point of the falling regression line Lr_F to the end point of ejection of the coating liquid from the nozzle 71 (time te). If te<t14, the termination approximation line Lr_e is omitted.

Furthermore, a steady straight line Lr_m is set for the section from time t12 to time t13. The steady straight line Lr_m is a straight line with zero slope indicating the steady pressure Pm. That is, the steady straight line Lr_m is a straight line indicating the steady pressure Pm that connects the end point (time t12) of the rising regression line Lr_R and the starting point (time t13) of the falling regression line Lr_F.

In this way, an approximate waveform WF1 composed of the start approximate straight line Lr_s, rising regression line Lr_R, steady straight line Lr_m, falling regression straight line Lr_F, and end approximate straight line Lr_e arranged in time series is calculated. Then, the pressure evaluation unit 913 calculates the average absolute error MAE (ideal trapezoidal absolute error) between the ejection pressure measurement data 99 and the approximate waveform WF1 in the entire ejection period Tt from the time ta to the time te as the characteristic quantity Fv1. Calculate as Further, the pressure evaluation unit 913 normalizes the feature amount Fv1 to a range of 0 or more and 2 or less based on a predetermined threshold Th1 (for example, 0.05). Specifically, if Fv1<Th1, then Fv1=0
If Fv1≧Th1, then Fv1=(Fv1+1−Th1)×c1
Based on, the feature quantity Fv1 is converted into a normalized feature quantity Fv1 (that is, the evaluation value V1). Here, the coefficient c1 is a normalization coefficient, and is set in advance to a value (for example, 15) that allows the feature quantity Fv1 to fall within a range of 2 or less.

According to the evaluation based on the feature value Fv1 in FIG. 7, when the time variation of the ejection pressure over the entire ejection period Tt deviates greatly from the ideal shape (that is, the trapezoidal shape), a large score is obtained for this ejection pressure. (i.e. bad rating).

FIG. 8 is a diagram for explaining evaluation items for evaluating the time change of the ejection pressure based on the feature amount Fv2. The evaluation item in FIG. 8 evaluates the smoothness of the rise of the discharge pressure. Specifically, curve regression analysis is performed on the change in discharge pressure over time between the lower reference pressure P2_l and the upper reference pressure P2_u, which is greater than the lower reference pressure P2_l, during the rising period Ta. A rising regression curve Nr is calculated. This curvilinear regression analysis is performed by a quadratic curve.

The lower reference pressure P2_l is set to the initial pressure Pi. On the other hand, the upper reference pressure P2_u is higher than the lower reference pressure P2_l and lower than the target pressure Pt. In this example, the upper reference pressure P2_u is a pressure obtained by adding 20% of the absolute value of the difference between the initial pressure Pi and the target pressure Pt to the initial pressure Pi. The rising regression curve Nr increases from the lower reference pressure P2_l (initial pressure Pi) to the upper reference pressure P2_u between time t21 and time t22. Note that the time t21 coincides with the time ta, and the time t22 is after the time ta and before the time tb.

Thus, the waveform WF2 composed of the rising regression curve Nr is calculated. Then, the pressure evaluation unit 913 calculates the root-mean-square error RMSE between the discharge pressure measurement data 99 and the waveform WF2 as the feature quantity Fv2 in the initial rise period Ta_s from time t21 to time t22. Further, the pressure evaluation unit 913 normalizes the feature amount Fv2 to a range of 0 or more and 2 or less based on a predetermined threshold Th2 (for example, 0.05). Specifically, if Fv2<Th2, then Fv2=0
If Fv2≧Th2 then Fv2=2
Based on, the feature quantity Fv2 is converted into a normalized feature quantity Fv2 (that is, the evaluation value V2).

According to the evaluation based on the feature value Fv2 in FIG. can give a high score (i.e. a bad rating). A curve that can be used for curve regression analysis is not limited to a quadratic curve, and another curve such as an exponential function may be used.

FIG. 9 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the feature amount Fv3. The evaluation item in FIG. 9 evaluates whether the rising period Ta is within a certain period. Specifically, the pressure evaluation unit 913 calculates the length of the rising period Ta from time ta to time tb required for the discharge pressure to increase from the initial pressure Pi to the target pressure Pt (=tb-ta) as the feature quantity Fv3. Calculate as Further, the pressure evaluation unit 913 normalizes the feature amount Fv3 to a range of 0 or more and 1 or less based on a predetermined threshold Th3 (for example, 350 ms). Specifically, if Fv3<Th3, then Fv3=0
If Fv3≧Th3 then Fv2=1
Based on, the feature amount Fv3 is converted into a normalized feature amount Fv3 (that is, the evaluation value V3).

According to the evaluation based on the feature value Fv3 in FIG. 9, a high score (that is, a bad evaluation) can be given to the discharge pressure that takes time to rise to the target pressure Pt.

FIG. 10A is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv4, and FIG. 10B is an example of the temporal change in discharge pressure determined to be inappropriate by the evaluation based on the feature amount Fv4. It is a figure which shows. The evaluation item in FIG. 10A evaluates the presence or absence of abnormality in the rise of the discharge pressure. Specifically, the pressure evaluation unit 913 calculates the first derivative D1 of the time change of the ejection pressure for the rising period Ta from the time ta to the time tb to obtain the first derivative waveform WF4.

Then, the pressure evaluation unit 913 obtains the number of times the one-time differential waveform WF4 intersects a predetermined threshold value Th4 in the rising period Ta as the feature amount Fv4. In the example of FIG. 10A, the once-differentiated waveform WF4 and the threshold Th4 (for example, 0.002) intersect at times t41 and t42, respectively, and the number of intersections (feature Fv4) is two. Further, the pressure evaluation unit 913 normalizes the feature amount Fv4 to a range of 0 or more and 1 or less. Specifically, if Fv4≦2, then Fv4=0
If Fv4>2 then Fv4=1
Based on, the feature quantity Fv4 is converted into a normalized feature quantity Fv4 (that is, the evaluation value V4).

According to the evaluation based on the feature value Fv4 in FIG. 10A, when there is a step in the time change of the ejection pressure in the rising period Ta (for example, as shown in FIG. 10B), a high score (that is, , bad evaluation).

FIG. 11A is a diagram for explaining evaluation items for evaluating changes in discharge pressure over time based on the feature amount Fv5, and FIG. 11B is an example of changes over time in discharge pressure determined to be inappropriate by the evaluation based on the feature amount Fv5. It is a figure which shows. The evaluation item in FIG. 11A evaluates the presence or absence of abnormality in the rise of the discharge pressure. Specifically, the pressure evaluation unit 913 calculates the second derivative D2 of the time change of the ejection pressure for the rising period Ta from the time ta to the time tb to obtain the second derivative waveform WF5.

Then, the pressure evaluation unit 913 obtains the number of times the absolute value of the twice-differentiated waveform WF5 intersects a predetermined threshold value Th5 in the rising period Ta as the feature amount Fv5. In the example of FIG. 11A, the absolute value of the twice-differentiated waveform WF5 and the threshold Th5 (for example, 0.0002) intersect at times t51, t52, t53, and t54, respectively, and the number of intersections (feature Fv5) is 4 times. Further, the pressure evaluation unit 913 normalizes the feature amount Fv5 to a range of 0 or more and 1 or less. Specifically, if Fv5=4, then Fv5=0
If Fv5≠4 then Fv5=1
Based on, the feature quantity Fv5 is converted into a normalized feature quantity Fv5 (that is, the evaluation value V5).

According to the evaluation based on the feature value Fv5 in FIG. 11A, when there is a step in the time change of the ejection pressure in the rising period Ta (for example, as shown in FIG. 11B), a high score (that is, , bad evaluation).

FIG. 12 is a diagram for explaining the evaluation items for evaluating the time change of the discharge pressure based on the characteristic quantity Fv6. The evaluation item in FIG. 12 evaluates whether or not the rise of the discharge pressure stalls in the second half. Specifically, the pressure evaluation unit 913 calculates the second derivative D2 of the time change of the discharge pressure for the rising period Ta from the time ta to the time tb to obtain the second derivative waveform WF6.

Then, in the rise period Ta, the pressure evaluation unit 913 determines the time T_1st when the twice-differentiated waveform WF6 is greater than a predetermined positive threshold (Th5), and the time T_1st when the twice-differentiated waveform WF6 exceeds a predetermined negative threshold (-Th5). A smaller time T_2nd is obtained. Here, the positive threshold and the negative threshold have the same absolute value (Th5) and different signs. The absolute value (Th5) of the positive and negative thresholds is equal to the threshold Th5 used in the evaluation using the feature quantity Fv5. Then, the pressure evaluation unit 913 obtains the ratio of these times (=T_1st/T_2nd) as the feature amount Fv6. Further, the pressure evaluation unit 913 uses the following formula Fv6=|1−Fv6|
Based on, the feature quantity Fv6 is transformed.

Further, the pressure evaluation unit 913 normalizes the feature amount Fv6 thus converted to a range of 0 or more and 2 or less using a predetermined threshold value Th6 (for example, 0.2). Specifically, if Fv6<Th6, then Fv6=0
If Fv6≧Th6 then Fv6=f(Fv6)
f(γ)=4×γ−0.8
Based on, the feature quantity Fv6 is converted into a normalized feature quantity Fv6 (that is, the evaluation value V6). Note that the function f(γ) with γ as a variable is not limited to this example, and can be arbitrarily changed.

The transport speed of the substrate S to be coated with the coating liquid reaches the target speed without stalling even in the second half of the acceleration period. Therefore, it is preferable that the ejection pressure applied to the coating liquid also reaches the target pressure Pt without stalling during the rising period Ta. On the other hand, according to the evaluation based on the feature value Fv6 in FIG. 12, when the discharge pressure stalls in the rising period Ta, a high score (that is, a bad evaluation) can be given to this discharge pressure.

FIG. 13 is a diagram for explaining the evaluation items for evaluating the time change of the discharge pressure based on the feature amount Fv7. The evaluation item in FIG. 13 evaluates the sharpness of the time change of the discharge pressure at the end of the rise. Specifically, linear regression analysis is performed on the change in the discharge pressure over time between the lower reference pressure P7_l and the upper reference pressure P7_u, which is greater than the lower reference pressure P7_l, during the rising period Ta. A rising end regression line Lr is calculated. Here, the lower reference pressure P7_l is a pressure obtained by adding 80% of the absolute value of the difference between the initial pressure Pi and the target pressure Pt to the initial pressure Pi, and the upper reference pressure P7_u is the initial pressure Pi and the target pressure Pt. This pressure is obtained by adding 90% of the absolute value of the difference from the pressure Pt to the initial pressure Pi, and the discharge pressure increases from the lower reference pressure P7_l to the upper reference pressure P7_u from time t71 to time t72. do.

This rising end stage regression line Lr increases with the lapse of time and reaches the steady pressure Pm (the average value of the discharge pressure during the steady period Tc) at time t73. In this way, the rising end regression line Lr is set for the section from time t71 to time t73. Furthermore, the pressure evaluation unit 913 sets an extended straight line Lm with a zero slope indicating the steady pressure Pm from time t73 to time tb. As described above, the time tb is the time when the discharge pressure reaches the target pressure Pt, and corresponds to the end time of the rising period Ta. That is, the extended straight line Lm is provided so as to extend from (the end of) the rising end regression line Lr to the end of the rising period Ta. If tb<t73, the extended straight line Lm is omitted.

In this way, an approximate waveform WF7 composed of the rising end regression line Lr and the extended straight line Lm arranged in time series is calculated. Then, the pressure evaluation unit 913 determines the difference between the discharge pressure measurement data 99 and the approximate waveform WF7 in the final rising period Ta_e from the time t72 when the discharge pressure reaches 90% of the target pressure Pt to the time tb when it reaches 100%. is calculated as the feature quantity Fv7. Specifically, the weight reference time width Tw=t73-t72 is set. Then, the weighted square root error sum is expressed by the following formula Fv7=(Σ(P_measure−WF7) ² ×W) ^1/2
P_measure = discharge pressure measurement data 99
W=1 in the range of time tb≦t73+2×Tw
W=w in the range of time tb>t73+2×Tw
w is a weighting factor greater than 1, and is calculated based on 10, for example.

Further, the pressure evaluation unit 913 normalizes the feature amount Fv7 to a range of 0 or more and 2 or less based on a predetermined threshold Th7 (for example, 0.6). Specifically, if Fv7<Th7, then Fv7=0
If Fv7≧Th7 then Fv7=Fv7/c7
c7 is an arbitrary positive constant, for example 1.1, so that the feature quantity Fv7 is converted into a normalized feature quantity Fv7 (that is, the evaluation value V7).

According to the evaluation based on the feature value Fv7 in FIG. 13, when the ejection pressure changes with time showing a rounded waveform with a weak rising force, the ejection pressure is given a high score (that is, a bad evaluation). be able to.

14A and 14B are diagrams for explaining evaluation items for evaluating the time change of the ejection pressure based on the feature amount Fv8. The evaluation item in FIG. 14 evaluates the degree of overshoot that occurs when the discharge pressure rises. Specifically, the pressure evaluation unit 913 obtains the sign (positive/negative) of the second derivative D2 of the discharge pressure at time t81 when the discharge pressure reaches the maximum value Pmax. Then, the pressure evaluation unit 913 calculates time t82 at which the sign of the second differential D2 of the discharge pressure switches twice from the sign at time t81. Then, the temporal change in the ejection pressure during the initial vibration period Tb_s from time t81 to time t82 is evaluated.

Specifically, the minimum value P8min of the time change of the discharge pressure during the initial vibration period Tb_s is obtained, and the smaller one of the steady pressure Pm and the pressure P8min is selected as the target pressure Pg. Then, the difference between the maximum pressure Pmax and the target pressure Pg, that is, the following formula Fv8 = Pmax - Pg
A feature amount Fv8 is calculated based on.

Furthermore, the pressure evaluation unit 913 normalizes the feature amount Fv8 to a range of 0 or more and 2 or less using a predetermined threshold Th8 (for example, 0.035). Specifically, if Fv8<Th8, then Fv8=0
If Fv8≧Th8 then Fv8=Fv8/c8
c8 is an arbitrary positive constant, for example 0.12, so that the feature quantity Fv8 is converted into a normalized feature quantity Fv8 (that is, the evaluation value V8).

According to the evaluation based on the feature value Fv8 in FIG. 14, when the momentum of the rise is strong and the time change of the discharge pressure indicates a large overshoot, a high score (that is, a bad evaluation) is given to this discharge pressure. can be done.

FIG. 15 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the feature amount Fv9. The evaluation item in FIG. 15 evaluates the stability of the ejection pressure change over time during the transition period Tb. Specifically, the pressure evaluation unit 913 calculates the discharge pressure in the transition period Tb and the steady pressure Pm, which is the average value of the discharge pressure in the steady period Tc, according to the following equation: Fv9=RMSE(P_measure, Pm)
P_measure = discharge pressure measurement data 99
Root-mean-square error RMSE (P_measure, Pm) is calculated as feature quantity Fv9 based on.

Furthermore, the pressure evaluation unit 913 normalizes the feature amount Fv9 to a range of 0 or more and 2 or less. Specifically, the following formula Fv9=Fv9/c9
c9 is an arbitrary positive constant, for example 0.04, so that the feature quantity Fv9 is converted into a normalized feature quantity Fv9 (that is, the evaluation value V9).

According to the evaluation based on the feature value Fv9 in FIG. 15, when the change in the discharge pressure over time indicates ringing in the transition period Tb, a high score (that is, a bad evaluation) can be given to this discharge pressure.

FIG. 16 is a diagram for explaining the evaluation items for evaluating the time change of the ejection pressure based on the feature amount Fv10. The evaluation item in FIG. 16 evaluates the stability of the discharge pressure over time during the constant pressure period Tbc. Specifically, the pressure evaluation unit 913 obtains the maximum value Pmax and the minimum value P10min of the discharge pressure during the constant pressure period Tbc. Then, the pressure evaluation unit 913 calculates the difference between the maximum pressure Pmax and the minimum pressure P10min in the constant pressure period Tbc, that is, the following formula Fv10=Pmax−P10min
Based on, the feature amount Fv10 is calculated.

Furthermore, the pressure evaluation unit 913 normalizes the feature amount Fv10 to a range of 0 or more and 2 or less using a threshold Th10 (for example, 0.12). Specifically, if Fv10<Th10, then Fv10=0
If Fv10≧Th10 then Fv10=Fv10/Th10
Based on, the feature quantity Fv10 is converted into a normalized feature quantity Fv10 (that is, the evaluation value V10).

According to the evaluation based on the feature value Fv10 in FIG. 16, when the time variation of the ejection pressure shows a large variation in the steady period Tc in which the film thickness of the coating liquid is greatly affected, a large score (that is, bad evaluation) can be given.

17A and 17B are diagrams for explaining evaluation items for evaluating the time change of the discharge pressure based on the feature amount Fv11. The evaluation item in FIG. 17 evaluates the straightness of the time change of the discharge pressure in the rising period Ta. Specifically, in the rising period Ta, the pressure increase period Tar from time t111 when the discharge pressure reaches the lower reference pressure P11_l to time t113 when the discharge pressure reaches the upper reference pressure P11_u, which is higher than the lower reference pressure P11_l. Desired. Here, the lower reference pressure P11_l is a pressure obtained by adding 20% of the absolute value of the difference between the initial pressure Pi and the target pressure Pt to the initial pressure Pi, and the upper reference pressure P11_u is the initial pressure Pi and the target pressure This pressure is obtained by adding 80% of the absolute value of the difference from the pressure Pt to the initial pressure Pi, and the discharge pressure increases from the lower reference pressure P11_l to the upper reference pressure P11_u from time t111 to time t113. do.

Furthermore, the pressure evaluation unit 913 obtains specific data Dm that satisfies a predetermined condition from the discharge pressure measurement data 99 between the lower reference pressure P11_l and the upper reference pressure P11_u. Such predetermined conditions will be described in detail below.

Among the discharge pressure measurement data 99, one measurement data between the lower reference pressure P11_l and the upper reference pressure P11_u is selected as the candidate data Dc. A regression line obtained by performing a linear regression analysis with respect to the change in discharge pressure over time between the measurement data Dl indicating the lower reference pressure P11_l and the candidate data Dc is defined as an approximate line Lr_1. A regression line obtained by performing a linear regression analysis with respect to the change in discharge pressure over time between the measurement data Du indicating the upper reference pressure P11_u and the candidate data Dc is assumed to be an approximate line Lr_2. Further, in the section between the measured data Dl and the candidate data Dc, the root mean square error RMSE (P_measure, Lr1) between the change in discharge pressure over time and the approximate straight line Lr_1 is obtained. Similarly, in the interval between the candidate data Dc and the measurement data Du, the root mean square error RMSE (P_measure, Lr2) between the change in discharge pressure over time and the approximate straight line Lr_2 is obtained. Here, P_measure indicates the ejection pressure measurement data 99 .

Furthermore, the sum of these is given by the following formula: Er=RMSE(P_measure, Lr1)+RMSE(P_measure, Lr2)
required based on Then, among the discharge pressure measurement data 99, the candidate data Dc with the smallest sum Er is specified as the specific data Dm.

Then, if the slopes of the approximate straight lines Lr_1 and Lr_2 obtained for the specific data Dm are K1 and K2, respectively, and the characteristic amount Fv11 is K1>K2, then Fv11=1−K1/K2
If K1≦K2 then Fv11=1−K2/K1
calculated based on

Further, the pressure evaluation unit 913 normalizes the feature amount Fv11 to a range of 0 or more and 1 or less based on a predetermined threshold Th11 (for example, 0.25). Specifically, if Fv11<Th11, then Fv11=0
If Fv11≧Th11 then Fv11=f(Fv11)
f(γ)=4×γ−1
Based on, the feature quantity Fv11 is converted into a normalized feature quantity Fv11 (that is, the evaluation value V11). Note that the function f(γ) with γ as a variable is not limited to this example, and can be arbitrarily changed.

According to the evaluation based on the feature value Fv11 in FIG. 17, when the ejection pressure shows a time change with poor straightness in the rising period Ta, a high score (that is, a bad evaluation) can be given to this ejection pressure. .

FIG. 18 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv12. The evaluation item in FIG. 18 evaluates the sharpness of the time change of the discharge pressure at the end of the rise. Specifically, linear regression analysis is performed on the change in discharge pressure over time between the lower reference pressure P12_l and the upper reference pressure P12_u that is greater than the lower reference pressure P12_l during the rising period Ta, A rising end regression line Lr is calculated. Here, the lower reference pressure P12_l is a pressure obtained by adding 70% of the absolute value of the difference between the initial pressure Pi and the target pressure Pt to the initial pressure Pi, and the upper reference pressure P12_u is the initial pressure Pi and the target pressure This pressure is obtained by adding 90% of the absolute value of the difference from the pressure Pt to the initial pressure Pi, and the discharge pressure increases from the lower reference pressure P12_l to the upper reference pressure P12_u from time t121 to time t122. do.

This rising end stage regression line Lr increases with the lapse of time and reaches the target pressure Pt at time t123. In this way, the rising end regression line Lr is set for the section from time t121 to time t123. Furthermore, the pressure evaluation unit 913 sets an extended straight line Lm with a zero slope indicating the target pressure Pt from time t123 to time tb. As described above, the time tb is the time when the discharge pressure reaches the target pressure Pt, and corresponds to the end time of the rising period Ta. That is, the extended straight line Lm is provided so as to extend from (the end of) the rising end regression line Lr to the end of the rising period Ta. If tb<t123, the extended straight line Lm is omitted.

In this way, an approximate waveform WF12 composed of the rising end regression line Lr and the extended straight line Lm arranged in time series is calculated. Then, the pressure evaluation unit 913 determines the difference between the discharge pressure measurement data 99 and the approximate waveform WF12 in the final rising period Ta_e from the time t122 when the discharge pressure reaches 90% of the target pressure Pt to the time tb when it reaches 100%. is calculated as the feature quantity Fv12. Specifically, the sum of square root errors is expressed by the following formula Fv12=(Σ(P_measure−WF12) ² ) ^1/2
P_measure = discharge pressure measurement data 99
Calculated based on

Further, the pressure evaluation unit 913 normalizes the feature amount Fv12 to a range of 0 or more and 1 or less based on a predetermined threshold Th12 (for example, 0.8). Specifically, if Fv12<Th12, then Fv12=0
If Fv12≧Th12 then Fv12=f(Fv12)
f(γ)=5×γ−4
Based on, the feature quantity Fv12 is converted into a normalized feature quantity Fv12 (that is, the evaluation value V12). Note that the function f(γ) with γ as a variable is not limited to this example, and can be arbitrarily changed.

According to the evaluation based on the feature value Fv12 in FIG. 18, when the rising force is weak and the change in ejection pressure over time shows a rounded waveform from a broad perspective, a high score (i.e., , bad evaluation).

FIG. 19 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the feature amount Fv13. The evaluation item in FIG. 19 evaluates the sharpness of the time change of the discharge pressure at the end of the rise. Specifically, linear regression analysis is performed on the change in the discharge pressure over time between the lower reference pressure P13_l and the upper reference pressure P13_u, which is greater than the lower reference pressure P13_l, during the rising period Ta. A rising end regression line Lr is calculated. Here, the lower reference pressure P13_l is a pressure obtained by adding 90% of the absolute value of the difference between the initial pressure Pi and the target pressure Pt to the initial pressure Pi. This pressure is obtained by adding 95% of the absolute value of the difference from the pressure Pt to the initial pressure Pi, and the discharge pressure increases from the lower reference pressure P13_l to the upper reference pressure P13_u from time t131 to time t132. do.

This rising end stage regression line Lr increases with the lapse of time and reaches the target pressure Pt at time t133. In this way, the rising end regression line Lr is set for the section from time t131 to time t133. Furthermore, the pressure evaluation unit 913 sets an extended straight line Lm with a zero slope indicating the target pressure Pt from time t133 to time tb. As described above, the time tb is the time when the discharge pressure reaches the target pressure Pt, and corresponds to the end time of the rising period Ta. That is, the extended straight line Lm is provided so as to extend from (the end of) the rising end regression line Lr to the end of the rising period Ta. If tb<t133, the extended straight line Lm is omitted.

In this way, the approximate waveform WF13 composed of the rising end regression line Lr and the extended straight line Lm arranged in time series is calculated. Then, the pressure evaluation unit 913 determines the difference between the discharge pressure measurement data 99 and the approximate waveform WF13 in the final rising period Ta_e from the time t132 when the discharge pressure reaches 95% of the target pressure Pt to the time tb when it reaches 100%. is calculated as the feature quantity Fv13. Specifically, the sum of square root errors is expressed by the following formula Fv13=(Σ(P_measure−WF13) ² ) ^1/2
P_measure = discharge pressure measurement data 99
Calculated based on

Further, the pressure evaluation unit 913 normalizes the feature amount Fv13 to a range of 0 or more and 1 or less based on a predetermined threshold Th13 (for example, 0.1). Specifically, if Fv13<Th13, then Fv13=0
If Fv13≧Th13 then Fv13=f(Fv13)
f(γ)=(10×γ−1)/3
Based on, the feature quantity Fv13 is converted into a normalized feature quantity Fv13 (that is, the evaluation value V13). Note that the function f(γ) with γ as a variable is not limited to this example, and can be arbitrarily changed.

According to the evaluation based on the feature value Fv13 in FIG. 19, when the rising force is weak and the temporal change in the ejection pressure shows a locally rounded waveform, a high score (i.e. , bad evaluation).

FIG. 20 is a diagram for explaining evaluation items for evaluating temporal change in discharge pressure based on the feature amount Fv14. The evaluation item in FIG. 20 evaluates the degree of overshoot that occurs when the discharge pressure rises. Specifically, the pressure evaluation unit 913 obtains the sign (positive/negative) of the second derivative D2 of the discharge pressure at time t141 when the discharge pressure reaches the maximum value Pmax. Then, the pressure evaluation unit 913 calculates time t142 at which the sign of the second differential D2 of the discharge pressure switches twice from the sign at time t141. Then, the temporal change in the ejection pressure during the initial vibration period Tb_s from time t141 to time t142 is evaluated.

Specifically, the minimum value P14min of the time change of the discharge pressure in this initial vibration period Tb_s is obtained. Then, the difference between the maximum pressure Pmax and the steady pressure Pm is expressed by the following formula OVER=Pmax−Pm
and the difference between the steady pressure Pm and the minimum pressure P14min is the following formula UNDER = Pm-P14min
Calculated based on and the sum of OVER and UNDER, ie Fv14=OVER+UNDER
A feature amount Fv14 is calculated based on.

Furthermore, the pressure evaluation unit 913 normalizes the feature amount Fv14 to a range of 0 or more and 1 or less using a predetermined threshold Th14 (for example, 0.01). Specifically, if Fv14<Th14, then Fv14=0
If Fv14≧Th14 then Fv14=f(Fv14)
f(γ)=(100×γ−1)/9
Based on, the feature quantity Fv14 is converted into a normalized feature quantity Fv14 (that is, the evaluation value V14).

According to the evaluation based on the feature value Fv14 in FIG. 20, the error from the target pressure Pt is calculated for each of the points of overshoot and ringback (a phenomenon in which the pressure drops due to reaction after a sudden rise). Therefore, when the discharge pressure exhibits a large overshoot or ringback over time, a high score (that is, a bad evaluation) can be given to this discharge pressure.

The above is a description of each evaluation item that can be used to evaluate the time change of the discharge pressure, and the feature amounts Fv1 to Fv14 and the evaluation values V1 to V14 extracted from each evaluation item. Note that in the measurement result evaluation in step S102, not all evaluation items are always evaluated, and the number of evaluation items to be evaluated changes according to the appropriateness of the discharge pressure change over time. Next, this point will be explained.

FIG. 21 is a flow chart showing the details of measurement result evaluation, and FIG. 22 is a diagram schematically showing an example of operations performed according to the flow chart of FIG. The measurement result evaluation in FIG. 21 is performed by the pressure evaluation unit 913 . In this measurement result evaluation, N evaluation stages (N is an integer equal to or greater than 2, N=3 in this example) are prepared, and these N evaluation stages are executed in order.

As shown in FIG. 22, evaluation items based on the feature amount Fv1 shown in FIG. 7 are assigned to the first (I=1) evaluation stage. Evaluation items based on the feature quantities Fv2 to Fv10 shown in FIGS. 8 to 16 are assigned to the second (I=2) evaluation stage. Evaluation items based on the feature amounts Fv11 to Fv14 shown in FIGS. 17 to 20 are assigned to the third (I=3) evaluation stage. Then, in each evaluation stage I, the time change of the ejection pressure is evaluated based on the assigned evaluation items. Note that I is a number for identifying the evaluation stage, and is an integer of 1 or more and N or less.

In this way, evaluation items different from each other are assigned to the N evaluation stages. Furthermore, final evaluation values Vf of different ranges (ranges) are assigned to the N evaluation stages. Therefore, as will be explained below, the discharge pressure evaluated by the I-th evaluation stage is given a final evaluation value Vf within the value range assigned to the I-th evaluation stage.

As shown in FIG. 21, in step S201, I is reset to zero, and in step S202, I is incremented by one. In step S203, the discharge pressure is evaluated based on the evaluation items of the I-th evaluation stage. Here, since I=1, the feature amount Fv1 is calculated to obtain the evaluation value V1. This evaluation value V1 is the evaluation result of the first evaluation stage.

In step S204, it is determined whether I=N. Here, since I<N, the process proceeds to step S205. In step S205, based on the evaluation result in step S203, it is determined whether or not the discharge pressure changes favorably with time. If the evaluation result (evaluation value V1) is equal to or greater than the predetermined sorting threshold At1, it is determined to be defective (NO) in step S205, and the second and third evaluation stages (that is, the evaluation stages after the Ith). The evaluation by is omitted, and the process proceeds to step S206.

In step S206, the final evaluation value Vf is determined according to the number (I) of evaluation stages that have been executed and the evaluation result in the I-th evaluation stage. In this example, since only the first evaluation stage has been executed, according to the example of FIG. 22, the evaluation result of the first evaluation stage ( A value obtained by adding the evaluation value V1) is determined as the final evaluation value Vf. As a result, the final evaluation value Vf within the value range (20 to 40) provided for the first evaluation stage is given to the time variation of the discharge pressure.

Alternatively, if the evaluation result (evaluation value V1) in step S204 is less than the sorting threshold value At1, it is determined to be good (YES) in step S205, the process returns to step S202, and I is incremented by one.

Then, in step S203, the discharge pressure is evaluated based on the evaluation items of the I-th evaluation stage. Here, since I=2, the feature quantities Fv2 to Fv10 are calculated to obtain the evaluation values V2 to V10. The sum of the evaluation values V2 to V10 is the evaluation result of the second evaluation stage. That is, the sum of the evaluation values of the evaluation items belonging to the I-th evaluation stage is the evaluation result of the I-th evaluation stage.

In step S204, it is determined whether I=N. Here, since I<N, the process proceeds to step S205. In step S205, based on the evaluation result in step S203, it is determined whether or not the discharge pressure changes favorably with time. If the evaluation result (sum of evaluation values V2 to V10) is equal to or greater than the predetermined sorting threshold value At2, it is determined to be defective (NO) in step S205, the evaluation in the third evaluation stage is omitted, and step S206 is performed. proceed to

In step S206, the final evaluation value Vf is determined according to the number (I) of evaluation stages that have been executed and the evaluation result in the I-th evaluation stage. In this example, since the 1st and 2nd evaluation stages have already been executed, according to the example of FIG. 22, the evaluation result of the second evaluation stage A value obtained by adding (total of evaluation values V2 to V10) is determined as the final evaluation value Vf. As a result, the final evaluation value Vf within the value range (4 to 20) provided for the second evaluation stage is given to the time variation of the discharge pressure.

Alternatively, if the evaluation result (total of evaluation values V2 to V10) in step S205 is less than the sorting threshold value At2, it is determined to be good (YES) in step S205, and the process returns to step S202 to increment I by 1. be done.

Then, in step S203, the discharge pressure is evaluated based on the evaluation items of the I-th evaluation stage. Here, since I=3, the feature quantities Fv11 to Fv14 are calculated to obtain the evaluation values V11 to V14. Then, similarly to the above, the sum of the evaluation values V11 to V14 is the evaluation result of the third evaluation stage.

In step S204, it is determined whether I=N. Here, since I=N, the process proceeds to step S206. In step S206, the final evaluation value Vf is determined according to the number (I) of evaluation stages that have been executed and the evaluation result in the I-th evaluation stage. In this example, since the 1st to 3rd evaluation stages have already been executed, according to the example of FIG. The sum of the values V11 to V14) is added to determine the final evaluation value Vf. As a result, the final evaluation value Vf within the value range (0 to 4) provided for the third evaluation stage is given to the time variation of the discharge pressure.

In the embodiment described above, N evaluation stages from the 1st to the Nth are provided in which the discharge pressure is evaluated by different evaluation items, respectively, and the evaluation stages from the 1st to the Nth are executed in order. can do. However, when the discharge pressure is determined to be appropriate in the evaluation of the evaluation items related to the I-th evaluation stage ("YES" in step S205), the discharge pressure is evaluated according to the evaluation items of the (I+1)th evaluation stage. On the other hand, if the discharge pressure is determined to be inappropriate in the evaluation of the evaluation items related to the I-th evaluation stage ("NO" in step S205), the evaluation stage after the I-th evaluation stage is performed. No discharge pressure evaluation is performed (ie, omitted). In other words, when the ejection pressure is evaluated in order by the 1st to Nth evaluation stages, if the ejection pressure is determined to be inappropriate in any of the evaluation stages, the subsequent evaluation stages are not evaluated. This makes it possible to evaluate the ejection pressure applied to the coating liquid in order to eject the coating liquid from the nozzle 71 in a reasonable amount of time according to the suitability of the ejection pressure.

Further, different final evaluation values Vf (evaluation values) are given to the discharge pressure according to the difference in the number (I) of the evaluation steps in which the discharge pressure is evaluated among the N evaluation steps. With such a configuration, a better final evaluation value Vf can be given to a discharge pressure with a greater number of evaluation steps performed, and an appropriate final evaluation value Vf according to the adequacy of the discharge pressure can be given to the discharge pressure. becomes.

Further, in the first evaluation stage, the ejection period Tt (first period, evaluation target period ), the discharge pressure is measured (step S101). Then, the ideal trapezoidal absolute error of the temporal change in the ejection pressure over the entire ejection period Tt is extracted as a feature amount Fv1 (first feature amount, overall feature amount), and the temporal change in the ejection pressure is evaluated based on this feature amount Fv1. (step S102). This makes it possible to reflect the suitability of the ejection pressure in the entire ejection period Tt from the start to the end of ejection of the coating liquid from the nozzle 71 in the evaluation of the ejection pressure.

Further, as shown in FIG. 7, the characteristic amount Fv1 includes an approximate waveform WF1 (first approximate waveform) that approximates the time change of the ejection pressure over the entire ejection period Tt, and the time change of the ejection pressure over the entire ejection period Tt. shows the difference between With such a configuration, the ejection pressure during the entire ejection period Tt can be appropriately evaluated based on the approximation waveform WF1 for the temporal change in the ejection pressure during the entire ejection period Tt from the start to the end of ejection of the coating liquid from the nozzles 71. .

In particular, the approximate waveform WF1 is
・From the initial pressure Pi (ejection start pressure) to the steady pressure Pm higher than the initial pressure Pi, by linearly approximating the change in the ejection pressure that increases with the passage of time after the ejection of the coating liquid from the nozzle 71 is started. A rising regression line Lr_R (rising approximate straight line) that linearly increases with the passage of time;
A start time approximate line Lr_s that indicates the initial pressure Pi provided between the start time (time ta) of the discharge of the coating liquid from the nozzle 71 and the rising regression line Lr_R;
・Before finishing the ejection of the coating liquid from the nozzle 71, by linearly approximating the time change of the ejection pressure that decreases with the passage of time, the initial pressure Pi (ejection end pressure) lower than the steady pressure Pm from the steady pressure Pm (ejection end pressure) A falling regression line Lr_F (falling approximate straight line) that linearly decreases over time to
an approximate end time line Lr_e that indicates the initial pressure Pi (ejection end pressure) provided between the falling regression line Lr_F and the end time (time te) of the ejection of the coating liquid from the nozzle 71;
- A steady straight line Lr_m indicating the steady pressure Pm connecting between the rising regression line Lr_R and the falling regression line Lr_F. In such a configuration, the time variation of the ejection pressure during the entire ejection period Tt from the start to the end of the ejection of the coating liquid from the nozzles 71 is approximated by a trapezoidal waveform, and the ejection pressure during the entire ejection period Tt is appropriately evaluated. can.

Further, in the second evaluation stage, feature amounts Fv2 to Fv10 (second feature amounts) possessed by temporal changes in the ejection pressure during a period shorter than the ejection period Tt (second period) of the ejection period Tt are extracted, A change in ejection pressure over time is evaluated based on the characteristic amounts Fv2 to Fv10 (step S102). With such a configuration, the ejection pressure can be evaluated with high accuracy based on the temporal change in the ejection pressure during a period shorter than the ejection period Tt from the start to the end of ejection of the coating liquid from the nozzles 71 .

Further, in the evaluation items shown in FIG. 8, the discharge pressure is evaluated in a predetermined rising initial period Ta_s (second period) from the start of discharge of the coating liquid from the nozzle 71 . Through this initial rise period Ta_s, the discharge pressure increases with time, and shows the difference between the rise regression curve Nr of the time change of the discharge pressure in the initial rise period Ta_s and the time change of the discharge pressure in the initial rise period Ta_s. A feature quantity Fv2 (second feature quantity) is extracted. With such a configuration, it is possible to evaluate the ejection pressure in consideration of the time change of the ejection pressure immediately after the start of the application liquid from the nozzle 71 .

In addition, the ejection pressure is evaluated during the rising period Ta (second period) from the start of ejection of the coating liquid from the nozzle 71 until the ejection pressure increases to the target pressure Pt (predetermined pressure). With such a configuration, the ejection pressure can be evaluated in consideration of the temporal change in the ejection pressure during the rising period Ta.

Specifically, in the evaluation items shown in FIG. 9, the length of the rising period Ta is extracted as the feature amount Fv2 (second feature amount). With such a configuration, the discharge pressure can be evaluated in consideration of the rising speed of the discharge pressure.

Further, in the evaluation items shown in FIGS. 10A and 10B, the number of times the one-time derivative D1 of the time variation of the discharge pressure intersects a predetermined threshold value Th4 during the rising period Ta is extracted as the feature amount Fv4 (second feature amount). be done. With such a configuration, the ejection pressure can be evaluated in consideration of the smoothness of the time change of the ejection pressure during the rising period.

Further, in the evaluation items shown in FIG. 11, the number of times the absolute value of the second differential D2 of the time change of the discharge pressure intersects a predetermined threshold value Th5 during the rise period Ta is extracted as a feature amount Fv5 (second feature amount). be done. With such a configuration, the ejection pressure can be evaluated in consideration of the smoothness of the time change of the ejection pressure in the rising period Ta.

Further, in the evaluation items shown in FIG. 12, in the rising period Ta, the time T_1st at which the second derivative D2 of the change in ejection pressure with time is greater than a predetermined positive threshold value (Th5), and the second derivative of the change in ejection pressure with time A ratio of time T_2nd at which D2 becomes smaller than a negative threshold (-Th5) having the same absolute value as the positive threshold is extracted as a feature quantity Fv6 (second feature quantity). With such a configuration, the ejection pressure can be evaluated by considering the difference in the time change of the ejection pressure between the initial stage and the final stage of the rising period Ta.

Further, in the evaluation items shown in FIG. 13, the discharge pressure is evaluated in the rising final period Ta_e (second period) until the discharge pressure increases to the target pressure Pt (predetermined pressure). That is, the feature quantity Fv7 (second feature quantity) indicating the difference between the approximation waveform WF7 (final rise approximate waveform) approximating the time change of the discharge pressure in the final rise period Ta_e and the time change of the discharge pressure in the final rise period Ta_e. is extracted. This approximation waveform WF7 is composed of a rising final stage regression line Lr (rising final stage approximation straight line) and an extended straight line Lm. The late rising regression line Lr overlaps the approximate curve obtained by linearly approximating the time change of the discharge pressure that increases with the passage of time in the pressure range (P7_l to P7_u) smaller than the target pressure Pt. increases linearly up to the steady-state pressure Pm. The extended straight line Lm extends from (at the end of) the rising final stage regression line Lr to the ending time of the rising final period Ta_e to indicate the steady pressure Pm. With such a configuration, the ejection pressure can be evaluated in consideration of the extent of the ejection pressure stall at the end of the rising period Ta.

Further, in the evaluation items shown in FIG. 14, from the time point (time t81) when the discharge pressure reaches the maximum value Pmax to the time point (time t82) when the second differential D2 of the time change of the discharge pressure crosses zero twice. The ejection pressure in the initial vibration period Tb_s (second period) is evaluated. Specifically, the minimum value P8min of the discharge pressure in the initial vibration period Tb_s is obtained, and the difference between the smaller one of the minimum value P8min and the steady pressure Pm and the maximum value Pmax of the discharge pressure is the characteristic It is extracted as the quantity Fv8 (second feature quantity). With such a configuration, the discharge pressure can be evaluated in consideration of the overshoot of the discharge pressure.

Further, in the evaluation items shown in FIG. 15, the discharge pressure is evaluated during a predetermined transition period Tb (second period) from the time (time tb) when the discharge pressure exceeds the target pressure Pt (predetermined pressure). Specifically, a feature quantity Fv9 (second feature quantity) representing the difference in discharge pressure during the rising period Ta with respect to the steady pressure Pm is extracted. With such a configuration, the discharge pressure can be evaluated in consideration of the stability of the discharge pressure after the discharge pressure reaches the target pressure Pt.

Further, in the evaluation items shown in FIG. 16, the discharge pressure starts to decrease toward the end of the discharge of the coating liquid from the nozzle 71 from the time (time tb) when the discharge pressure exceeds the target pressure Pt (predetermined pressure). The discharge pressure in the constant pressure period Tbc up to time (time td) is evaluated. Specifically, a characteristic quantity Fv10 is extracted that indicates the difference between the maximum value Pmax and the minimum value P10min of the discharge pressure during the constant pressure period Tbc. With such a configuration, the ejection pressure can be evaluated in consideration of the stability of the ejection pressure during the constant pressure period Tbc of the ejection pressure.

Further, in the third evaluation stage, feature amounts Fv11 to Fv14 (third feature amounts) possessed by temporal changes in the ejection pressure during a period shorter than the ejection period Tt (third period) of the ejection period Tt are extracted, A change in ejection pressure over time is evaluated based on the feature amounts Fv11 to Fv14 (step S102). With such a configuration, the ejection pressure can be evaluated with high accuracy based on the temporal change in the ejection pressure during a period shorter than the ejection period Tt from the start to the end of ejection of the coating liquid from the nozzles 71 .

Further, in the evaluation items shown in FIG. 17, the ejection pressure changes from the lower reference pressure P11_l (lower reference value) to the upper reference pressure P11_u (upper reference value) with the passage of time after the start of ejection of the coating liquid from the nozzle 71. The discharge pressure in the increasing pressure rise period Tar (third period) is evaluated. Specifically, one measurement data of the discharge pressure measurement data 99 between the lower reference pressure P11_l and the upper reference pressure P11_u, and the section between the lower reference pressure P11_l and the one measurement data In (t111 to t112), the interval (t112 At t113), one measurement value is obtained that minimizes the sum of the root-mean-square error between the approximate straight line Lr_2 obtained by linear regression with respect to the time change of the discharge pressure and the time change of the discharge pressure. Then, the ratio of the slope K1 of the straight line between the lower reference pressure P11_l and the one measurement data and the slope K2 of the straight line between the one measurement data and the upper reference pressure P11_u is the feature quantity Fv11 (the first 3 feature quantity). With such a configuration, the ejection pressure can be evaluated by considering the linearity of the increase in the ejection pressure.

Further, in the evaluation items shown in FIG. 18, the discharge pressure is evaluated in the rising final period Ta_e (third period) until the discharge pressure increases to the target pressure Pt (predetermined pressure). That is, the feature quantity Fv12 (third feature quantity) indicating the difference between the approximate waveform WF12 (final rise approximate waveform) that approximates the time change of the discharge pressure in the final rise period Ta_e and the time change of the discharge pressure in the final rise period Ta_e. is extracted. Here, the end-of-rise approximation waveform WF12 is composed of the end-of-rise regression line Lr and the extended straight line Lm. The late-rising regression line Lr overlaps the approximation curve obtained by linearly approximating the time change of the discharge pressure that increases with time in the pressure range (P12_l to P12_u) smaller than the target pressure Pt. increases linearly up to the target pressure Pt. The extended straight line Lm is extended from (at the end of) the rising final stage regression line Lr to the ending time of the rising final period Ta_e, and indicates the target pressure Pt. With such a configuration, the ejection pressure can be evaluated in consideration of the extent of the ejection pressure stall at the end of the rising period Ta.

Further, in the evaluation items shown in FIG. 19, the discharge pressure is evaluated during the rising final period Ta_e (third period) until the discharge pressure increases to the target pressure Pt (predetermined pressure). That is, the feature quantity Fv13 (third feature quantity) indicating the difference between the approximation waveform WF13 (final rise approximate waveform) that approximates the time change of the discharge pressure during the final rise period Ta_e and the time change of the discharge pressure during the final rise period Ta_e. is extracted. Here, the end-of-rise approximation waveform WF13 is composed of the end-of-rise regression line Lr and the extended straight line Lm. The late-rising regression line Lr overlaps the approximation curve obtained by linearly approximating the change in the discharge pressure that increases with time in the pressure range (P13_l to P13_u) smaller than the target pressure Pt. increases linearly up to the target pressure Pt. The extended straight line Lm is extended from (at the end of) the rising final stage regression line Lr to the ending time of the rising final period Ta_e, and indicates the target pressure Pt. With such a configuration, the ejection pressure can be evaluated in consideration of the extent of the ejection pressure stall at the end of the rising period Ta.

Further, in the evaluation items shown in FIG. 20, from the time when the discharge pressure reaches the maximum value Pmax (time t141) to the time when the second differential D2 of the time change of the discharge pressure crosses zero twice (time t142) The ejection pressure in the initial vibration period Tb_s (third period) is evaluated. Specifically, the feature value Fv14 (the 3 feature quantity). With such a configuration, the discharge pressure can be evaluated in consideration of the overshoot of the discharge pressure.

As described above, in the above embodiments, the coating device 1 corresponds to an example of the "substrate processing device" of the present invention, the nozzle 71 corresponds to an example of the "nozzle" of the present invention, and the coating liquid supply mechanism 8 corresponds to an example of the "nozzle" of the present invention. The nozzle 71 and the coating liquid supply mechanism 8 cooperate to constitute an example of the "ejection device" of the present invention, and the pressure gauge 86 is an example of the "measurement section" of the present invention. The control unit 9 corresponds to an example of the "computer" and the "control section" of the present invention, the discharge pressure evaluation program 97 corresponds to an example of the discharge pressure evaluation program of the present invention, and the recording medium M corresponds to the present invention. The coating liquid corresponds to an example of the "recording medium" of the invention, the pressure measured by the pressure gauge 86 corresponds to an example of the "ejection pressure" of the invention.

Further, the ejection period Tt corresponds to an example of the "first period" of the present invention, the feature quantity Fv1 corresponds to an example of the "first feature quantity" of the present invention, and the approximate waveform WF1 corresponds to the "first approximate period" of the present invention. The initial pressure Pi corresponds to an example of the "discharge start pressure" and the "discharge end pressure" of the present invention, and the rise regression line Lr_R corresponds to an example of the "rise approximate straight line" of the present invention. , the approximate straight line at the start Lr_s corresponds to an example of the "approximate straight line at the start" of the present invention, the falling regression line Lr_F corresponds to an example of the "approximate straight line at the fall" of the present invention, and the approximate straight line at the end Lr_e corresponds to the present invention. It corresponds to an example of the "approximation straight line at the end" of the invention, and the steady straight line Lr_m corresponds to an example of the "steady straight line" of the invention.

Furthermore, the initial rising period Ta_s, the rising period Ta, the final rising period Ta_e, the initial vibration period Tb_s, the transition period Tb, and the constant pressure period Tbc correspond to an example of the "second period" of the present invention, and the feature amounts Fv2 to Fv10 correspond to the present invention. The initial period Ta_s corresponds to an example of the "second feature amount" of the invention, the initial period Ta_s corresponds to an example of the "rising initial period" of the invention, and the regression curve Nr corresponds to an example of the "regression curve" of the invention. The period Ta corresponds to an example of the "rising period" of the present invention, the final rising period Ta_e corresponds to an example of the "final rising period" of the present invention, and the approximate waveform WF7 corresponds to an example of the "final rising approximate waveform" of the present invention. , the final rise regression line Lr corresponds to an example of the "final rise approximate straight line" of the present invention, the extended straight line Lm corresponds to an example of the "extended straight line" of the present invention, and the initial vibration period Tb_s corresponds to the present The steady period Tc corresponds to an example of the "steady period" of the present invention, the transition period Tb corresponds to an example of the "transition period" of the present invention, and the constant pressure period Tbc. corresponds to an example of the "constant pressure period" of the present invention.

Further, the pressure rise period Tar, the rising final period Ta_e, and the initial vibration period Tb_s correspond to an example of the "third period" of the present invention, and the feature amounts Fv11 to Fv14 correspond to an example of the "third feature amount" of the present invention. The lower reference pressure P11_l corresponds to an example of the "lower reference value" of the present invention, the upper reference pressure P11_u corresponds to an example of the "upper reference value" of the present invention, and the pressure increase period Tar corresponds to an example of the "upper reference value" of the present invention. It corresponds to an example of the "pressure rise period", the rising final period Ta_e corresponds to an example of the "final rising period" of the present invention, and the approximate waveforms WF12 and WF13 correspond to an example of the "final rising approximate waveform" of the present invention. , the final rise regression line Lr corresponds to an example of the "final rise approximate straight line" of the present invention, the extended straight line Lm corresponds to an example of the "extended straight line" of the present invention, and the initial vibration period Tb_s corresponds to the " It corresponds to an example of "initial vibration period".

The present invention is not limited to the above-described embodiments, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, the discharge characteristics are measured based on the pressure value detected by the pressure gauge 86 attached to the pipe 82 , but the mounting position of the pressure gauge 86 is not limited to this, and The mounting position is arbitrary as long as the pressure of the supplied coating liquid can be detected.

Further, in the above embodiment, the bellows type pump 81 is used, but the type of pump is not limited to this. For example, a syringe type pump using a piston (for example, JP-A-2008-101510) may be used.

In the above embodiment, the present invention is applied to the coating apparatus 1 that supplies the coating liquid to the surface Sf of the substrate S while the substrate S is being floated, but the application of the present invention is limited to this. The present invention can be applied to general substrate processing techniques in which a processing liquid is supplied to a nozzle to supply the processing liquid from the nozzle to the upper surface of the substrate to perform a predetermined processing.

Further, in the second evaluation stage, it is not essential to evaluate the discharge pressure based on all of the feature quantities Fv2 to Fv10, and the discharge pressure may be evaluated based on only some of them. good too. Similarly, for the third evaluation stage, the discharge pressure may be evaluated based on only part of the feature quantities Fv11 to Fv14.

Further, in calculating the approximate waveform WF1 in FIG. 7, a straight line with a zero gradient indicating the target pressure Pt may be used instead of the steady straight line Lr_m.

Also, it is not always necessary to prepare all three evaluation stages. Therefore, among the above first to third evaluation stages, only the first and second evaluation stages may be executed, or only the second and third evaluation stages may be executed. Alternatively, it may be configured to perform only the first and third stages of evaluation. Alternatively, an evaluation stage may be provided in which the ejection pressure is evaluated using evaluation items different from the three evaluation stages described above.

Further, in obtaining the final evaluation value Vf, when obtaining the sum of each evaluation value (for example, V2 to V10, V11 to V14) at the corresponding evaluation stage, the evaluation value is multiplied by a different weighting factor to perform weighting. you can go

Further, instead of the feature amount Fv1 shown in FIG. 7, a feature amount Fv1_1 described in the next modified example may be calculated, and the time change of the ejection pressure may be evaluated based on this feature amount Fv1_1. FIG. 23 is a diagram for explaining each period used in the modified example of the ejection pressure evaluation item, and FIG. It is a diagram. Here, the differences between FIG. 23 and FIG. 5 will be mainly described, and the common points will be denoted by corresponding reference numerals and the description thereof will be omitted as appropriate. Similarly, the differences between FIG. 24 and FIG. 7 will be mainly described, and the common points will be denoted by corresponding reference numerals, and the description thereof will be omitted as appropriate.

As shown in FIG. 23, in the modified example of the evaluation item, attention period Troi is used. This attention period Troi is a period from time ta to time td. That is, the period of interest Troi is composed of the rising period Ta, the transition period Tb and the steady period Tc, in other words, the period of interest Troi is composed of the rising period Ta and the constant pressure period Tbc. In this way, the period of interest Troi is defined as the "main period from when the treatment liquid is started to be discharged from the nozzle to when the discharge pressure starts to decrease from the predetermined pressure after the discharge pressure rises to a predetermined pressure." , and the target pressure Pt corresponds to an example of the "predetermined pressure" of the present invention.

As shown in FIG. 24, in this modified example, the rise regression line Lr_R is calculated and the approximate line Lr_s at the start is set in the same manner as the feature amount Fv1 described above. Furthermore, in the period from time t12 to time td, a steady straight line Lr_m_1 is set, which is a straight line with zero gradient indicating the steady pressure Pm (that is, the average of the measured values of the discharge pressure during the steady period Tc).

In this way, an approximate waveform WF1_1 composed of the starting time approximate straight line Lr_s, rising regression line Lr_R, and stationary straight line Lr_m_1 arranged in time series is calculated. Then, the pressure evaluation unit 913 calculates the average absolute error MAE between the discharge pressure measurement data 99 and the approximate waveform WF1_1 as the feature quantity Fv1_1 in the entire period of interest Troi from time ta to time td. Also, the pressure evaluation unit 913 normalizes the feature amount Fv1_1 to a predetermined range based on a predetermined threshold Th1_1 (for example, 0.05). Specifically, if Fv1_1<Th1_1, then Fv1_1=0
If Fv1_1≧Th1_1, then Fv1_1=(Fv1_1+1-Th1_1)×c1_1
, the feature quantity Fv1_1 is converted into a normalized feature quantity Fv1_1 (that is, the evaluation value V1_1). Here, the upper limit of Fv1_1 is 2×c1_1, and the coefficient c1_1 is a normalization coefficient and is an arbitrary positive constant. Note that the specific method of normalizing the feature quantity Fv1_1 is not limited to the example here, and may be changed as appropriate.

According to the evaluation based on the feature value Fv1_1 in FIG. 24, when the time change of the ejection pressure in the entire period of interest Troi deviates greatly from the ideal shape, a high score (that is, a bad evaluation) is given to this ejection pressure. can give

In this modification, in the measurement result evaluation (step S102) of the discharge pressure evaluation shown in FIG. calculate. In particular, the evaluation based on the feature quantity Fv1_1 shown in FIG. 24 is assigned to the first (I=1) evaluation stage instead of the evaluation based on the feature quantity Fv1 shown in FIG. Then, measurement result evaluation shown in FIG. 21 is performed. That is, in the table of FIG. 22, the feature amount of the evaluation item when the evaluation level I is 1 is not the feature amount Fv1 but the feature amount Fv1_1 shown in FIG.

Also in this modification, there are provided N evaluation stages from 1st to Nth in which the discharge pressure is evaluated by different evaluation items, respectively, and the evaluation stages from 1st to Nth are executed in order. can be done. However, when the discharge pressure is determined to be appropriate in the evaluation of the evaluation items related to the I-th evaluation stage ("YES" in step S205), the discharge pressure is evaluated according to the evaluation items of the (I+1)th evaluation stage. On the other hand, if the discharge pressure is determined to be inappropriate in the evaluation of the evaluation items related to the I-th evaluation stage ("NO" in step S205), the evaluation stage after the I-th evaluation stage is performed. No discharge pressure evaluation is performed (ie, omitted). In other words, when the ejection pressure is evaluated in order by the 1st to Nth evaluation stages, if the ejection pressure is determined to be inappropriate in any of the evaluation stages, the subsequent evaluation stages are not evaluated. This makes it possible to evaluate the ejection pressure applied to the coating liquid in order to eject the coating liquid from the nozzle 71 in a reasonable amount of time according to the suitability of the ejection pressure.

Also, a period of interest Troi (main period , evaluation period), the ejection pressure is measured. Then, in the first (I=1) evaluation stage, the feature amount Fv1_1 (overall feature amount) of the change in ejection pressure over time in the entire period of interest Troi is extracted, and the change in ejection pressure over time is calculated based on the feature amount Fv1_1. evaluated. This makes it possible to reflect in the evaluation of the ejection pressure whether or not the ejection pressure is appropriate in the entire period of interest Troi, which affects the thickness of the treatment liquid applied to the substrate S.

Furthermore, in this modification, when the period of interest Troi has a particularly large effect on the thickness of the treatment liquid applied to the substrate S (in other words, when the period after the period of interest Troi has a small effect). In addition, it is possible to reflect the appropriateness of the ejection pressure in the entire period of interest Troi in the evaluation of the ejection pressure.

Further, the feature amount Fv1_1 (main feature amount) is an approximate waveform WF1_1 (main approximate waveform) that approximates the time change of the discharge pressure over the entire period of interest Troi (main period), and the time period of the discharge pressure over the entire period of interest Troi. Show change and difference. With such a configuration, the ejection pressure during the entire attention period Troi can be appropriately evaluated based on the approximation waveform WF1_1 for the temporal change of the ejection pressure during the entire attention period Troi.

In particular, the approximate waveform WF1_1 is
Time elapses from the initial pressure Pi (ejection start pressure) to a steady pressure Pm greater than the initial pressure Pi, which is a linear approximation of the time change in the ejection pressure that increases with the passage of time after the ejection of the coating liquid from the nozzle 71 is started. A rising regression line Lr_R (rising approximate straight line) that linearly increases with
A start time approximate line Lr_s that indicates the initial pressure Pi provided between the start time (time ta) of the discharge of the coating liquid from the nozzle 71 and the rising regression line Lr_R;
A steady straight line Lr_m_1 indicating the steady pressure Pm is provided during the period from when the rising regression line Lr_R reaches the steady pressure Pm to the end of the period of interest Troi (between time t12 and time td). With such a configuration, it is possible to appropriately evaluate the ejection pressure during the entire attention period Troi by approximating the time change of the ejection pressure during the entire attention period Troi.

Incidentally, when the discharge pressure is evaluated using the feature value Fv1_1 shown in FIG. 24, it is not necessary to measure the discharge pressure in the period after the period of interest Troi (that is, the falling period Td) in step S101. .

Further, the UI 95 may be configured to select which of the above-described two feature amounts Fv1 and Fv1_1 is used to evaluate the discharge pressure. In this case, in step S102, one of the feature amounts Fv1 and Fv1_1 selected by the user's input operation to the UI 95 is used to evaluate the discharge pressure. In the measurement result evaluation of FIG. 21, for the first (I=1) evaluation stage, the ejection pressure is evaluated using one of the feature amounts Fv1 and Fv1_1.

INDUSTRIAL APPLICABILITY The present invention can be applied to general substrate processing techniques in which a processing liquid is supplied to a nozzle so that the processing liquid is discharged from the nozzle onto a substrate with target characteristics.

1... Coating device (substrate processing device)
71 Nozzle (ejection device)
8... Coating liquid supply mechanism (pressure application unit, ejection device)
86 ... pressure gauge (measuring part)
9... Control unit (computer, control section)
97 Ejection pressure evaluation program M Recording medium Tt Ejection period (first period)
Fv1... feature amount (first feature amount)
WF1: Approximate waveform (first approximate waveform)
Pi ... initial pressure (discharge start pressure, discharge end pressure)
Lr_R: Rise regression line (Rise approximate straight line)
Lr_s ... Approximate straight line at the start Lr_F ... Falling regression line Lr_e ... Approximate straight line at the end Lr_m ... Steady straight line Ta_s ... Rising initial period (second period)
Ta: rising period (second period)
Ta_e ... rising final period (second period)
Tb_s: initial vibration period (second period)
Tb ... transition period (second period)
Tbc: Constant pressure period (second period)
Fv2 to Fv10... feature quantity (second feature quantity)
Nr... Regression curve WF7... Approximate waveform (rising final approximate waveform)
Lr ... rising end regression line (rising end approximation straight line)
Lm... Extended straight line Tc... Steady period Tar... Pressure increase period (third period)
Ta_e ... rising final period (third period)
Tb_s: initial vibration period (third period)
Fv11 to Fv14... feature quantity (third feature quantity)
P11_l: Lower reference pressure (lower reference value)
P11_u ... Upper reference pressure (upper reference value)
Tar... Pressure rise period Ta_e... Rise end period WF12, WF13... Approximate waveform (rise end approximate waveform)
Lr ... rising end regression line (rising end approximation straight line)
Lm...extended straight line Tb_s...initial vibration period

Claims (27)

First to Nth (N is an integer equal to or greater than 2) evaluation stages for evaluating the discharge pressure of a discharge device that applies a discharge pressure to a treatment liquid and discharges the treatment liquid from a nozzle, respectively, according to different evaluation items. a step of evaluating the discharge pressure according to the evaluation item related to the first evaluation stage;
(I+1)-th evaluation when the discharge pressure is determined to be appropriate in the evaluation by the evaluation items related to the I-th evaluation stage (I is an integer equal to or greater than 1 and less than N) among the N evaluation stages. While executing the evaluation of the discharge pressure according to the evaluation items related to the stage, if the discharge pressure is determined to be inappropriate in the evaluation according to the evaluation items related to the I-th evaluation stage, after the I-th evaluation stage and a step of not performing the evaluation of the discharge pressure according to the evaluation stages in the order of . 2. The discharge pressure evaluation method according to claim 1, wherein different evaluation values are given to the discharge pressure according to the number of evaluation steps in which the discharge pressure is evaluated among the N evaluation steps. In the evaluation target period including at least a major period from when the treatment liquid is started to be discharged from the nozzle to when the discharge pressure increases to a predetermined pressure and when the discharge pressure starts to decrease from the predetermined pressure, a step of extracting, as an overall feature amount, a feature amount of the temporal change in the ejection pressure over the entire evaluation target period, based on the result of measuring the ejection pressure;
3. The first evaluation step according to claim 1, wherein the first evaluation stage includes an evaluation item for evaluating the discharge pressure by performing a step of evaluating the time change of the discharge pressure based on the overall feature amount. Discharge pressure evaluation method. The evaluation target period is the main period,
4. The discharge pressure evaluation method according to claim 3, wherein a main feature quantity, which is a feature quantity of the change in the discharge pressure over time in the entire main period, is extracted as the overall feature quantity. 5. The ejection according to claim 4, wherein the main characteristic amount indicates a difference between a main approximate waveform approximating a time change of the discharge pressure over the entire main period and a time change of the discharge pressure over the main period. Pressure evaluation method. The main approximation waveform is
A linear approximation of the change in the ejection pressure over time that increases with the lapse of time after the start of ejection of the treatment liquid from the nozzle, and the increase linearly with the lapse of time from the ejection start pressure to a steady pressure higher than the ejection start pressure. and a rising approximation line
a start-time approximate line indicating the ejection start pressure provided between the start point of ejection of the treatment liquid from the nozzle and the rise approximate straight line;
6. A discharge pressure evaluation method according to claim 5, wherein said rising approximation straight line has a steady straight line indicating said steady pressure, which is provided from reaching said steady pressure to the end of said main period. The evaluation target period is a first period from the start of ejection of the treatment liquid from the nozzle to the end of ejection of the treatment liquid from the nozzle,
4. The discharge pressure evaluation method according to claim 3, wherein a first feature quantity, which is a feature quantity of the change in the discharge pressure over time in the entire first period, is extracted as the overall feature quantity. 8. The first characteristic amount indicates a difference between a first approximate waveform that approximates the time change of the discharge pressure over the entire first period and the time change of the discharge pressure over the first period. The discharge pressure evaluation method described in . The first approximate waveform is
After the start of ejection of the treatment liquid from the nozzle, by linearly approximating the time change of the ejection pressure that increases with the passage of time, from the ejection start pressure to a steady pressure higher than the ejection start pressure with the passage of time A rising approximate straight line that increases linearly,
a start-time approximate line indicating the ejection start pressure provided between the start point of ejection of the treatment liquid from the nozzle and the rise approximate straight line;
By linearly approximating the change in the ejection pressure that decreases with the passage of time before the ejection of the treatment liquid from the nozzle is completed, the steady pressure is reduced to an ejection end pressure lower than the steady pressure with the passage of time. a falling approximation line that linearly decreases with
a termination time approximation line indicating the ejection termination pressure provided between the falling approximation line and the termination point of ejection of the treatment liquid from the nozzle;
9. The discharge pressure evaluation method according to claim 8, further comprising a steady straight line connecting said rising approximation straight line and said falling approximation straight line and indicating said steady pressure. a step of extracting, as a second feature amount, a characteristic amount of the temporal change in the discharge pressure in a second period shorter than the evaluation period, out of the evaluation period;
evaluating the change over time of the discharge pressure based on the second feature amount, and the second evaluation step of the N evaluation steps is the evaluation item for evaluating the discharge pressure. The discharge pressure evaluation method according to any one of claims 3 to 9. A predetermined rising initial period from the start of ejection of the treatment liquid from the nozzle is set as the second period,
The discharge pressure increases with the lapse of time throughout the initial rising period,
11. The second feature quantity according to claim 10, wherein a feature quantity indicating a difference between a regression curve of the time change of the discharge pressure in the initial rise period and the time change of the discharge pressure in the initial rise period is extracted as the second feature quantity. Discharge pressure evaluation method. 12. The ejection pressure evaluation method according to claim 10, wherein a rising period from the start of ejection of the treatment liquid from the nozzle until the ejection pressure increases to the predetermined pressure is set as the second period. 13. The discharge pressure evaluation method according to claim 12, wherein the length of the rising period is extracted as the second feature amount. 14. The ejection pressure evaluation method according to claim 12 or 13, wherein the number of times the first derivative of the time variation of the ejection pressure intersects a predetermined threshold during the rising period is extracted as the second characteristic amount. 15. The second feature amount according to any one of claims 12 to 14, wherein the number of times an absolute value of the second derivative of the time variation of the discharge pressure intersects a predetermined threshold during the rising period is extracted as the second feature amount. Discharge pressure evaluation method. In the rising period, the time during which the second derivative of the change in the discharge pressure with time is greater than a predetermined positive threshold, and the second derivative of the change in the discharge pressure with time have the same absolute value as the positive threshold. 16. The discharge pressure evaluation method according to any one of claims 12 to 15, wherein a ratio of the time during which is smaller than a negative threshold value of is extracted as the second feature amount. A predetermined rise final period until the discharge pressure increases to the predetermined pressure is set as the second period,
extracting a feature quantity indicating a difference between a final rise approximate waveform approximating the time change of the discharge pressure in the final rise period and the time change of the discharge pressure in the final rise period as the second feature quantity,
The rising terminal approximation waveform is
It overlaps with the approximation curve obtained by linearly approximating the time change of the discharge pressure that increases with the passage of time in the pressure range smaller than the predetermined pressure, and the discharge pressure in the steady period after the final rise period. A rise terminal approximation line that linearly increases with the passage of time up to a steady pressure that is the average value of time changes,
17. The discharge pressure evaluation method according to any one of claims 10 to 16, further comprising an extended straight line indicating the steady pressure, which is extended from the final rise approximate straight line to the end of the final rise period. An initial oscillation period from the time when the discharge pressure reaches the maximum value to the time when the second derivative of the time change of the discharge pressure crosses zero twice is set as the second period,
The difference between the minimum value of the discharge pressure in the initial vibration period and the average value of the discharge pressure in a predetermined steady period after the initial vibration period, whichever is smaller, and the maximum value of the discharge pressure is The discharge pressure evaluation method according to any one of claims 10 to 17, which is extracted as the second feature amount. A predetermined transition period from the time when the discharge pressure exceeds the predetermined pressure is set as the second period,
19. A feature quantity indicating a difference in the discharge pressure during the transition period from an average value of the discharge pressure during a predetermined steady period after the transition period is extracted as the second feature quantity. The discharge pressure evaluation method according to claim 1. A constant pressure period from when the ejection pressure exceeds the predetermined pressure to when the ejection pressure starts to decrease toward the end of ejection of the treatment liquid from the nozzle is set as the second period,
The discharge pressure evaluation method according to any one of claims 10 to 19, wherein a feature quantity indicating a difference between the maximum value and the minimum value of the discharge pressure during the constant pressure period is extracted as the second feature quantity. The discharge pressure evaluation method according to any one of claims 10 to 20, wherein N is 3 or more,
a step of extracting, as a third feature amount, a characteristic amount of the temporal change in the ejection pressure in a third period shorter than the evaluation period, out of the evaluation period;
evaluating the change over time of the discharge pressure based on the third characteristic amount, and the third evaluation step of the N evaluation steps is the evaluation item for evaluating the discharge pressure. Discharge pressure evaluation method. a pressure increase period during which the ejection pressure increases from a lower reference value to an upper reference value larger than the lower reference value over time after the start of ejection of the treatment liquid from the nozzle is set as the third period;
one of the discharge pressure measurements between the lower reference value and the upper reference value,
a root-mean-square error between the approximate straight line obtained by linear regression with respect to the time change of the discharge pressure and the time change of the discharge pressure in the interval between the lower reference value and the one measured value;
In the section between the one measured value and the upper reference value, the sum of the root mean square error between the approximate straight line obtained by linear regression with respect to the time change of the discharge pressure and the time change of the discharge pressure is minimized. obtaining said one measurement;
A ratio of the slope of the straight line between the lower reference value and the one measured value and the slope of the straight line between the one measured value and the upper reference value is extracted as the third feature quantity. 22. The discharge pressure evaluation method according to claim 21. A predetermined rising final period until the discharge pressure increases to the predetermined pressure is set as the third period,
A feature quantity indicating a difference between a final rise approximation waveform that approximates the time change of the discharge pressure in the final rise period and the time change of the discharge pressure in the final rise period is extracted as the third feature quantity,
The rising terminal approximation waveform is
Overlaps the approximation curve obtained by linearly approximating the time change of the discharge pressure that increases with time in a pressure range lower than the predetermined pressure, and rises to the predetermined pressure with the passage of time. an approximating straight line,
23. A discharge pressure evaluation method according to claim 21 or 22, further comprising an extended straight line indicating said predetermined pressure connected to said rising final stage approximation straight line. An initial oscillation period from the time when the discharge pressure reaches the maximum value to the time when the second derivative of the time change of the discharge pressure crosses zero twice is set as the third period,
A value obtained by subtracting a steady pressure, which is an average value of the discharge pressure in a predetermined steady period after the initial vibration period, from the maximum value of the discharge pressure, and a value of the discharge pressure in the initial vibration period from the steady pressure 24. The discharge pressure evaluation method according to any one of claims 21 to 23, wherein the sum of the value obtained by subtracting the minimum value is extracted as the third feature amount. First to Nth (N is an integer equal to or greater than 2) evaluation stages for evaluating the discharge pressure of a discharge device that applies a discharge pressure to a treatment liquid and discharges the treatment liquid from a nozzle, respectively, according to different evaluation items. a step of evaluating the discharge pressure according to the evaluation item related to the first evaluation stage;
(I+1)-th evaluation when the discharge pressure is determined to be appropriate in the evaluation by the evaluation items related to the I-th evaluation stage (I is an integer equal to or greater than 1 and less than N) among the N evaluation stages. While executing the evaluation of the discharge pressure according to the evaluation items related to the stage, if the discharge pressure is determined to be inappropriate in the evaluation according to the evaluation items related to the I-th evaluation stage, after the I-th evaluation stage A discharge pressure evaluation program for causing a computer to execute a step of not executing the evaluation of the discharge pressure according to the evaluation steps in the order of . A computer-readable recording medium for recording the ejection pressure evaluation program according to claim 25. a nozzle;
a pressure applying unit that applies a discharge pressure to the treatment liquid to cause the nozzle to discharge the treatment liquid;
a measurement unit that measures the discharge pressure;
First to Nth (N is an integer equal to or greater than 2) evaluation stages for evaluating the discharge pressure of a discharge device that applies a discharge pressure to a treatment liquid and discharges the treatment liquid from a nozzle, respectively, according to different evaluation items. and a control unit that stores the execution contents in
The control unit
Evaluating the discharge pressure according to the evaluation item related to the first evaluation stage among the N evaluation stages,
(I+1)-th evaluation when the discharge pressure is determined to be appropriate in the evaluation by the evaluation items related to the I-th evaluation stage (I is an integer equal to or greater than 1 and less than N) among the N evaluation stages. While executing the evaluation of the discharge pressure according to the evaluation items related to the stage, if the discharge pressure is determined to be inappropriate in the evaluation according to the evaluation items related to the I-th evaluation stage, after the I-th evaluation stage A substrate processing apparatus that does not perform the evaluation of the ejection pressure according to the evaluation steps in the order of .

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