TWI832505B - Discharge pressure evaluation method, discharge pressure evaluation program, recording medium and substrate processing apparatus - Google Patents

Abstract

According to the present invention, the adequacy of the discharge pressure during the entire period from the start to the end of discharge of the treatment liquid from the nozzle can be reflected in the evaluation of the discharge pressure. In the present invention, the discharge pressure is measured during the discharge period Tt (first period) from the start of discharge of the coating liquid (processing liquid) from the nozzle 71 to the end of the discharge of the coating liquid from the nozzle 71 . Next, the ideal trapezoidal absolute error of the time change of the discharge pressure in the entire discharge period Tt is extracted as a feature value Fv1 (first feature value), and the time change of the discharge pressure is evaluated based on this feature value Fv1.

Description

Discharge pressure evaluation method, discharge pressure evaluation program, recording medium and substrate processing device

The present invention relates to a technology for discharging a processing liquid from a nozzle by applying a discharge pressure to the processing liquid. In addition, the object to which the processing liquid is discharged from the nozzle includes, for example, a semiconductor substrate, a photomask substrate, a liquid crystal display substrate, an organic EL display substrate, a plasma display substrate, and a FED (Field Emission Display). Used substrates, optical disk substrates, magnetic disk substrates, optical disk substrates, etc.

As shown in Japanese Patent Laid-Open No. 2011-005465 and Japanese Patent Laid-Open No. 2020-040046, when the processing liquid discharged from the nozzle is applied to the substrate, the discharge pressure given to the processing liquid has a greater impact on the processing liquid applied to the substrate. The thickness has a greater impact. Here, in Japanese Patent Application Laid-Open No. 2011-005465, the waveform of the discharge pressure is divided into a plurality of sections, and whether the discharge pressure is within the allowable range is evaluated based on the slope of the waveform in each section. Furthermore, in Japanese Patent Application Laid-Open No. 2020-040046, parameters related to the discharge pressure are optimized for each region such as a rising region or a stable discharge region.

However, the above-mentioned technique divides and evaluates the period from the start to the end of discharge of the treatment liquid from the nozzle. Therefore, the appropriateness of the discharge pressure is not reflected in the evaluation of the discharge pressure during the entire period during which the thickness of the treatment liquid applied to the substrate is affected, and it may not necessarily be called an appropriate evaluation of the discharge pressure. In particular, the main period from when the treatment liquid starts to be discharged from the nozzle, when the discharge pressure rises to a predetermined pressure, to when the discharge pressure starts to decrease from the predetermined pressure is considered to be very important. Therefore, the above-described technology is not sufficient in terms of obtaining an evaluation that reflects the discharge pressure in the entire period including at least the main period.

The present invention was accomplished in view of the above-mentioned problems, and an object thereof is to reflect the adequacy of the discharge pressure in the evaluation of the discharge pressure in the entire period during which the thickness of the processing liquid applied to the substrate is affected.

The discharge pressure evaluation method of the present invention includes the step of measuring the discharge pressure during an evaluation target period including at least a main period in which the processing liquid is discharged from the nozzle by applying a discharge pressure to the processing liquid. The discharge device starts to discharge the treatment liquid from the nozzle, passes through the period when the discharge pressure rises to a predetermined pressure, and ends when the discharge pressure starts to decrease from the predetermined pressure; extract the characteristic amount of the temporal change of the discharge pressure in the entire evaluation target period , as a step of the overall feature quantity; and a step of evaluating the time change of the discharge pressure based on the overall feature quantity.

The discharge pressure evaluation program of the present invention causes a computer to execute a step of measuring the discharge pressure in an evaluation target period including at least a main period in which the processing liquid is discharged from the nozzle by applying a discharge pressure to the process liquid. The liquid discharge device starts to discharge the treatment liquid from the nozzle, passes through the period when the discharge pressure rises to a predetermined pressure, and ends when the discharge pressure starts to decrease from the predetermined pressure; the characteristic of the temporal change of the discharge pressure in the entire evaluation target period is extracted The step is to use the quantity as the overall characteristic quantity; and the step is to evaluate the time change of the discharge pressure based on the overall characteristic quantity.

The recording medium of the present invention includes the above-mentioned discharge pressure evaluation program, and the discharge pressure evaluation program is recorded in a computer-readable manner.

The substrate processing apparatus of the present invention is provided with: a nozzle; a pressure applying part that applies a discharge pressure to the processing liquid to cause the nozzle to discharge the processing liquid; a measuring part that measures the discharge pressure; and a control part that includes at least a main period. During the evaluation target period, the discharge pressure measured by the measuring unit is obtained, where the above-mentioned main period is the period from when the treatment liquid is discharged from the nozzle, through the discharge pressure rising to a predetermined pressure, until the discharge pressure starts to decrease from the predetermined pressure; control The characteristic quantity of the temporal change of the discharge pressure in the entire evaluation target period is extracted as the overall characteristic quantity, and the temporal variation of the discharge pressure is evaluated based on the overall characteristic quantity.

In the invention thus constituted (discharge pressure evaluation method, discharge pressure evaluation program, recording medium, and substrate processing apparatus), the discharge pressure is measured during an evaluation target period including at least a main period starting from the beginning. The period from when the nozzle discharges the treatment liquid to when the discharge pressure rises to a predetermined pressure until the discharge pressure starts to decrease from the predetermined pressure. Furthermore, the characteristic quantity of the temporal change of the discharge pressure in the entire evaluation target period is extracted as the overall characteristic quantity, and the temporal variation of the discharge pressure is evaluated based on the overall characteristic quantity. This allows the adequacy of the discharge pressure in the entire period that affects the thickness of the processing liquid applied to the substrate (in other words, the evaluation target period) to be reflected in the evaluation of the discharge pressure.

In addition, the discharge pressure evaluation method may be configured such that the evaluation target period is a main period, and the main characteristic quantity that is a characteristic quantity of the temporal change of the discharge pressure in the entire main period is extracted as the overall characteristic quantity. In this structure, when the main period has a particularly large influence on the thickness of the processing liquid applied to the substrate (in other words, when the period after the main period has only a slight influence), the discharge pressure can be appropriately adjusted throughout the main period. Sexuality is reflected in the evaluation of the vomiting pressure.

In addition, the discharge pressure evaluation method may be configured such that the main characteristic quantity represents the difference between a main approximate waveform that approximates the time change of the discharge pressure in the entire main period and the time change of the discharge pressure in the entire main period. In this configuration, the discharge pressure in the entire main period can be appropriately evaluated based on the approximate waveform corresponding to the time change of the discharge pressure in the entire main period.

In addition, the discharge pressure evaluation method can also be configured such that the main approximate waveform has a rising approximate straight line that increases linearly with the passage of time from the discharge start pressure to a stable pressure that is greater than the discharge start pressure. It is a straight line that approximates the time change of the discharge pressure that increases with the passage of time after the treatment liquid is started to be discharged from the nozzle. It is an approximate straight line at the beginning and is set between the time point when the treatment liquid is started to be discharged from the nozzle and the rising approximate straight line. The period represents the discharge start pressure; and the stable straight line is set between the time when the approximate straight line rises to the stable pressure and the end of the main period, which represents the stable pressure. In this configuration, the discharge pressure in the entire main period can be appropriately evaluated by approximating the time change of the discharge pressure in the entire main period.

In addition, the discharge pressure evaluation method may be configured such that the evaluation target period is the first period from the time when the nozzle discharges the processing liquid to the end of the nozzle discharge of the processing liquid, and the time changes of the discharge pressure in the entire first period may be extracted. The first characteristic quantity is the characteristic quantity, which is used as the overall characteristic quantity. In this structure, when the discharge pressure affects the thickness of the processing liquid applied to the substrate during the first period from the start of the discharge of the processing liquid from the nozzle to the end of the discharge of the processing liquid from the nozzle, the entire first period can be centered. The appropriateness of the discharge pressure is reflected in the evaluation of the discharge pressure.

In addition, the discharge pressure evaluation method may be configured such that the first characteristic amount represents a difference between a first approximate waveform that approximates the time change of the discharge pressure in the entire first period and the time change of the discharge pressure in the entire first period. . In this configuration, it is possible to appropriately evaluate the discharge pressure during the entire period from the start to the end of the discharge of the treatment liquid from the nozzle based on the approximate waveform relative to the time change of the discharge pressure.

In addition, the discharge pressure evaluation method may be configured such that the first approximate waveform has a rising approximate straight line, which is a straight line that approximates the time change of the discharge pressure that increases with the passage of time after starting to discharge the treatment liquid from the nozzle, Thereby, the pressure from the discharge start pressure to the stable pressure which is greater than the discharge start pressure increases linearly with the passage of time; the beginning is approximately a straight line, which is set at the start time point of discharge of the treatment liquid from the nozzle and rises approximately The straight line represents the discharge start pressure; the falling approximate straight line is a straight line that approximates the time change of the discharge pressure that decreases with the passage of time before finishing discharging the treatment liquid from the nozzle. Accordingly, from the stable pressure to the more stable pressure is The discharge end pressure decreases linearly with the passage of time until the discharge end pressure is small; the end approximate straight line is set between the drop approximate straight line and the end time point of discharging the treatment liquid from the nozzle, indicating the discharge end pressure; and the stable straight line, It connects the rising approximate straight line and the falling approximate straight line to represent stable pressure. In this configuration, the time change of the discharge pressure in the entire period from the start of the nozzle to the end of discharge of the treatment liquid can be made closer to a trapezoidal waveform, and the adequacy of the discharge pressure in the entire period can be evaluated.

In addition, the discharge pressure evaluation method may also be configured to further include the step of extracting, as the second feature, a characteristic amount of the temporal change in the discharge pressure in a second period that is shorter than the evaluation target period. The step of measuring: evaluating the time change of the discharge pressure based on the overall characteristic quantity and the second characteristic quantity. In this configuration, the discharge pressure can be evaluated with high accuracy based on the time change of the discharge pressure in both the entire period from the start to the end of discharge of the treatment liquid from the nozzle and the period shorter than this period.

In addition, the discharge pressure evaluation method may also be configured such that a predetermined initial period of rise from when the nozzle starts to discharge the treatment liquid is set as the second period, and the discharge pressure increases with the passage of time during the entire initial period of rise. The difference between the regression curve of the time change of the discharge pressure during the initial rise period and the time change of the discharge pressure during the initial rise period is extracted as a second feature value. In this configuration, the discharge pressure can be evaluated by adding the temporal change in the discharge pressure immediately after the nozzle discharges the treatment liquid.

In addition, the discharge pressure evaluation method may be configured such that the rising period from when the nozzle starts discharging the processing liquid until the discharge pressure increases to a predetermined pressure is set as the second period. In this configuration, the discharge pressure can be evaluated by adding the time change of the discharge pressure during the rising period.

Specifically, the discharge pressure evaluation method may be configured to extract the length of the rising period as the second feature quantity. In this configuration, the discharge pressure can be evaluated by adding the rise rate of the discharge pressure.

In addition, the discharge pressure evaluation method may be configured to extract the number of times that the first derivative of the time change of the discharge pressure crosses a predetermined threshold value during the rising period as the second characteristic quantity. In this configuration, the discharge pressure can be evaluated taking into account the smoothness of the temporal change of the discharge pressure during the rising period.

In addition, the discharge pressure evaluation method may be configured to extract the number of times the absolute value of the second derivative of the time change of the discharge pressure crosses a predetermined threshold value during the rising period as the second characteristic quantity. In this configuration, the discharge pressure can be evaluated taking into account the smoothness of the temporal change of the discharge pressure during the rising period.

In addition, the discharge pressure evaluation method may also be configured as follows: during the rising period, the second derivative of the time change of the discharge pressure becomes larger than the predetermined positive threshold value, and the second derivative of the time change of the discharge pressure The ratio of the time at which the negative threshold value becomes smaller than the predetermined negative threshold value having the same absolute value as the positive threshold value is extracted as the second feature quantity. In this configuration, the discharge pressure can be evaluated by taking into account the difference in temporal changes in the discharge pressure at the initial and final stages of the rise period.

In addition, the discharge pressure evaluation method may be configured such that a predetermined rise end period until the discharge pressure increases to a predetermined pressure is set as the second period, and the rise end period is approximated to a time change of the discharge pressure during the rise end period. The difference between the waveform and the time change of the discharge pressure during the final period of rise is extracted. As the second characteristic quantity, the approximate waveform at the end of rise has: the approximate straight line at the end of rise, which is approximated by a straight line. The time change of the discharge pressure that increases with the passage of time in a pressure range with a smaller predetermined pressure overlaps with the obtained approximate curve, and the average value of the time change of the discharge pressure in the stable period after the rising terminal period is stable. The pressure increases linearly as time passes; and an extended straight line extends from an approximate straight line at the end of the rise to the end time point of the final rise period, indicating stable pressure. In this configuration, the discharge pressure can be evaluated by adding the stall degree of the discharge pressure at the end of the rising period.

In addition, the discharge pressure evaluation method may be configured such that 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 to In the second period, the difference between the minimum value of the discharge pressure in the initial vibration period, the average value of the discharge pressure in the predetermined stable period after the initial vibration period, whichever is smaller, and the maximum value of the discharge pressure is extracted. as the second feature quantity. In this configuration, the discharge pressure can be evaluated by adding the overshoot of the discharge pressure.

In addition, the discharge pressure evaluation method may also be configured such that a predetermined transition period from the time point when the discharge pressure exceeds the predetermined pressure is set as the second period, and the discharge pressure during the transition period is compared with the discharge during the predetermined stable period after the transition period. From the difference between the average values of the pressures, a feature quantity representing the difference is extracted as the second feature quantity. In this configuration, the discharge pressure can be evaluated by taking into account the stability of the discharge pressure after the discharge pressure reaches a predetermined pressure.

In addition, the discharge pressure evaluation method may be configured such that the constant pressure period from the time when the discharge pressure exceeds the predetermined pressure to the time when the discharge pressure starts to decrease toward the end of discharging the treatment liquid from the nozzle is set as the third During the second period, a feature quantity representing the difference between the maximum value and the minimum value of the discharge pressure in the constant pressure period is extracted as the second feature quantity. In this configuration, the discharge pressure can be evaluated by taking into account the stability of the discharge pressure during the constant pressure period.

As described above, according to the present invention, the adequacy of the discharge pressure in the entire period from the start to the end of discharge of the treatment liquid from the nozzle can be reflected in the evaluation of the discharge pressure.

FIG. 1 is a diagram schematically showing the overall structure of a coating device, which is one embodiment of the substrate processing apparatus of the present invention. This coating device 1 is a slit coater that applies a coating liquid to the upper surface Sf of a substrate S that is conveyed in a horizontal posture from the left-hand side to the right-hand side in FIG. 1 . In addition, in the following figures, in order to clarify the arrangement relationship of each part of the device, the conveying direction of the substrate S is referred to as the "X direction", and the horizontal direction from the left-hand side to the right-hand side in Figure 1 is referred to as "+ X direction", and the opposite direction is called "-X direction". In addition, in the horizontal direction Y orthogonal to the X direction, the front side of the device is called the "-Y direction" and the back side of the device is called the "+Y direction". Furthermore, the upper direction and the lower direction in the vertical direction Z are called "+Z direction" and "-Z direction" respectively.

In the coating device 1 , an input conveyor 100 , an input transfer unit 2 , a floating platform unit 3 , an output transfer unit 4 , and an output conveyor are disposed in close proximity in this order along the transfer direction Dt (+X direction) of the substrate S. As will be described in detail below, the machine 110 forms a conveyance path of the substrate S extending in a substantially horizontal direction. In addition, in the following description, when the positional relationship is expressed in association with the conveyance direction Dt of the substrate S, the "upstream side in the conveyance direction Dt of the substrate S" may be simply referred to as "the upstream side", and the "substrate S" may also be referred to as "the upstream side". The "downstream side of the conveyance direction Dt of S" is simply called the "downstream side". In this example, when viewed from a certain reference position, the opposite (-X) side is equivalent to the "upstream side" and the opposite (+X) side is equivalent to the "downstream side".

The substrate S that is the processing object is carried into the input conveyor 100 from the left hand side in FIG. 1 . The input conveyor 100 is provided with a roller conveyor 101 and a rotation drive mechanism 102 for rotationally driving. By the rotation of the roller conveyor 101, the substrate S is conveyed in a horizontal posture toward the downstream side, that is, in the (+X) direction. . The input transfer unit 2 is provided with a roller conveyor 21 and a rotation/lifting drive mechanism 22 that has a function of rotating the roller conveyor 21 and a function of raising and lowering the roller conveyor 21 . As the roller conveyor 21 rotates, the substrate S is further conveyed in the (+X) direction. In addition, the position of the substrate S in the vertical direction Z is changed by the lifting and lowering of the roller conveyor 21 . The substrate S is transferred from the input conveyor 100 to the floating platform unit 3 by the input transfer unit 2 configured in this way.

The floating platform part 3 is provided with a flat platform divided into three parts along the conveyance direction Dt of the substrate. That is, the floating platform part 3 is equipped with the inlet floating platform 31, the coating platform 32, and the outlet floating platform 33, and the upper surfaces of these platforms become part of the same plane mutually. Furthermore, the floating platform part 3 has a lifting pin driving mechanism 34, a floating control mechanism 35, and a lifting driving mechanism 36. The lifting pin driving mechanism 34 can raise and lower the lifting pin provided on the entrance floating platform 31 . The floating control mechanism 35 can supply compressed air for floating the substrate S to each platform of the floating platform part 3 . The lifting drive mechanism 36 can raise and lower the outlet floating platform 33 .

A plurality of ejection holes are provided in a matrix on the upper surface of each of the inlet floating platform 31 and the outlet floating platform 33. These ejection holes eject the compressed air supplied from the floating control mechanism 35. The buoyancy given by the air flow causes the substrate S to float. In this way, the lower surface Sb of the substrate S is supported in a horizontal posture while being separated from the upper surface of the platform. The distance between the lower surface Sb of the substrate S and the upper surface of the platform, that is, the floating amount, can be set to 10 microns to 500 microns, for example.

On the other hand, on the upper surface of the coating platform 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 platform are alternately arranged. The floating control mechanism 35 controls the ejection amount of the compressed air from the ejection hole and the suction amount from the suction hole, thereby precisely controlling the distance between the lower surface Sb of the substrate S and the upper surface of the coating platform 32 . Thereby, the position of the upper surface Sf of the substrate S passing above the coating platform 32 in the vertical direction Z is controlled to a predetermined value. The specific structure of the floating platform portion 3 can be applied to the invention described in Japanese Patent No. 5346643, for example. Furthermore, the floating amount on the coating platform 32 is calculated by the control unit 9 based on the detection results detected by the sensors 61 and 62, which will be described in detail later, and can be achieved with high accuracy through air flow control. to make adjustments.

The substrate S carried into the floating platform part 3 via the input transfer part 2 is given a propulsive force in the (+X) direction by the rotation of the roller conveyor 21, and is transported to the entrance floating platform 31. The inlet floating platform 31, the coating platform 32 and the outlet floating platform 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 floating platform part 3 by the substrate transporting part 5 arranged below the inlet floating platform 31 , the coating platform 32 and the outlet floating platform 33 .

The substrate transfer unit 5 is equipped with: a chuck mechanism 51 that partially abuts the lower surface peripheral portion of the substrate S to support the substrate S from below; and an adsorption/transfer control mechanism 52 that has a function to control the substrate S. The suction pad (not shown) of the suction member provided at the upper end of the chuck mechanism 51 has the function of applying negative pressure to suction and hold the substrate S, and the function of reciprocating the chuck mechanism 51 in the X direction. When the chuck mechanism 51 holds the substrate S, the lower surface Sb of the substrate S is located at a higher position than the upper surface of each platform of the floating platform portion 3 . Therefore, the peripheral edge portion of the substrate S is adsorbed and held by the chuck mechanism 51 , and the overall horizontal posture is maintained by the buoyancy force imparted from the floating platform portion 3 . Furthermore, in the stage where the lower surface Sb of the substrate S is partially held by the chuck mechanism 51, in order to detect the position of the upper surface of the substrate S in the vertical direction Z, the sensor 61 for plate thickness measurement is arranged on the roller conveyor. Near machine 21. Directly below the sensor 61, there is a chuck (not shown) that does not hold the substrate S. With this, the sensor 61 can detect the upper surface of the adsorption member, that is, it can detect The position of the adsorption surface in the vertical direction Z is detected.

The chuck mechanism 51 holds the substrate S carried from the input transfer part 2 to the floating platform part 3. In this state, the chuck mechanism 51 is moved in the (+X) direction, whereby the substrate S is floated from the inlet. The upper part of the lifting platform 31 is conveyed toward the upper part of the exit floating platform 33 via the upper part of the coating platform 32 . The transported substrate S is delivered to the output transfer unit 4 arranged on the (+X) side of the outlet floating platform 33 .

The output transfer unit 4 is provided with a roller conveyor 41 and a rotation/lifting drive mechanism 42 that has a function of rotating and driving the roller conveyor 41 and a function of raising and lowering the roller conveyor 41 . The rotation of the roller conveyor 41 imparts a propulsive force in the (+X) direction to the substrate S, thereby conveying the substrate S along the conveyance direction Dt. In addition, the position of the substrate S in the vertical direction Z is changed by the lifting and lowering of the roller conveyor 41 . The substrate S is transferred to the output conveyor 110 from above the outlet floating platform 33 by the output transfer unit 4 .

The output conveyor 110 is equipped with a roller conveyor 111 and a rotation drive mechanism 112 that drives the rotation. By the rotation of the roller conveyor 111, the substrate S is further conveyed in the (+X) direction, and finally the substrate S is transported in the (+X) direction. The coating device 1 is sent out. Furthermore, the input conveyor 100 and the output conveyor 110 may be provided as a part of the coating device 1 , or may be separated from the coating device 1 . In addition, for example, a substrate feeding mechanism of another unit provided on the upstream side of the coating device 1 may be used as the input conveyor 100 . In addition, the substrate receiving mechanism of another unit provided on the downstream side of the coating device 1 may also be used as the output conveyor 110 .

A coating mechanism 7 for applying a coating liquid to the upper surface Sf of the substrate S is disposed on the conveyance path of the substrate S conveyed in this way. The coating mechanism 7 has a slit nozzle (hereinafter referred to as "nozzle") 71 having a slit-shaped discharge port. In addition, although illustration is omitted, a positioning mechanism is connected to the nozzle 71, and the nozzle 71 is positioned at the coating position above the coating platform 32 (the position indicated by a solid line in FIG. 1) by the positioning mechanism, or as explained later. Maintain location. Furthermore, the 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 the discharge port opening downward at the lower part of the nozzle.

FIG. 2 is a diagram showing the structure of the coating liquid supply mechanism. As shown in FIG. 2 , the coating liquid supply mechanism 8 uses a pump 81 that delivers the coating liquid through volume change as a delivery source for delivering the coating liquid to the nozzle 71 . As the pump 81, for example, a bellows type pump described in Japanese Patent Application Laid-Open No. 10-61558 can be used. The pump 81 has a flexible tube 811 that is elastically expandable and contractible in the radial direction. One end of the flexible tube 811 is connected to the coating liquid replenishing unit 83 through a pipe 82 , and the other end is connected to the nozzle 71 through a pipe 84 .

Outside the flexible tube 811, a bellows 812 is arranged that is elastically deformable in the axial direction. This bellows 812 has a small bellows part 813 and a large bellows part 814, and a non-compressible medium is sealed in the pump chamber 815 between the flexible tube 811 and the bellows 812. In addition, an actuating disk portion 816 is provided between the small bellows portion 813 and the large bellows portion 814 . A driving part 817 is connected to the actuating plate part 816 . When the driving part 817 operates in response to the command from the control unit 9, the actuating disk part 816 is displaced in the axial direction in a predetermined movement pattern (a pattern indicating the speed change of the actuating disk part 816 with respect to the passage of time), causing ripples The volume inside tube 812 changes. Thereby, the flexible tube 811 expands and contracts in the radial direction to perform a pump operation, which transports the coating liquid appropriately supplied from the coating liquid replenishing unit 83 toward the nozzle 71 . Therefore, the movement pattern of the actuating disk portion 816 is closely related to the discharge characteristics (time change of the discharge pressure) of the coating liquid discharged from the nozzle 71, and predetermined discharge characteristics corresponding to the movement pattern can be obtained.

The coating liquid replenishing unit 83 has a storage tank 831 for storing coating liquid. This storage tank 831 is connected to the pump 81 through a pipe 82 . In addition, an opening and closing valve 833 is inserted in the pipe 82 . The on-off valve 833 is opened in response to the replenishment command from the control unit 9, and can replenish the coating liquid in the storage tank 831 to the flexible tube 811 of the pump 81. On the contrary, it is closed in response to the replenishment stop command from the control unit 9 to limit replenishment of the coating liquid from the storage tank 831 to the flexible tube 811 of the pump 81 .

An opening and closing valve 85 is inserted in the pipe 84 connected to the output side of the pump 81 (the left hand side in the figure), and opens and closes in response to an opening and closing command from the control unit 9 . Thereby, it is possible to switch between feeding and stopping the coating liquid to the nozzle 71 . In addition, a pressure gauge 86 is attached to the pipe 84 and detects the pressure (discharge pressure) of the coating liquid sent to the nozzle 71 and outputs 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 floating height detection sensor 62 for detecting the floating height of the substrate S in a non-contact manner. The sensor 62 can measure the distance between the floating substrate S and the upper surface of the coating platform 32, and the control unit 9 controls the positioning mechanism (not shown) in response to the detected value. Thereby, the descending position of the nozzle 71 is adjusted. Furthermore, the sensor 62 may use an optical sensor, an ultrasonic sensor, or the like.

In order to perform predetermined maintenance on the nozzle 71, as shown in FIG. 1, the coating mechanism 7 is provided with a nozzle cleaning standby unit 72. The nozzle cleaning standby unit 72 mainly includes a drum 721, a cleaning part 722, a drum tank 723, and the like. Furthermore, by performing nozzle cleaning and droplet formation, the discharge port of the nozzle 71 is 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 installed, that is, the maintenance position. In order to evaluate the discharge pressure applied to the coating liquid, a simulated discharge of the coating liquid from the nozzle 71 is performed.

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 structure of the control unit. As shown in FIG. 3 , the control unit 9 is a computer and includes a computing unit 91 , a memory unit 93 and a UI (User Interface) 95 . The arithmetic unit 91 is a processor composed of a CPU (Central Processing Unit) and the like, and executes the discharge pressure evaluation program 97 to construct a measurement execution unit 911 that performs the measurement of the discharge pressure, and performs the measurement of the discharge pressure. The pressure evaluation unit 913 evaluates the discharge pressure. The memory unit 93 is a memory device such as HDD (Hard Disk Drive) or SSD (Solid State Drive), which stores the above-mentioned discharge pressure evaluation program 97 and executes the discharge pressure evaluation program 97 The measured discharge pressure measurement data is 99. This discharge pressure evaluation program 97 is provided by, for example, a recording medium M provided separately from the control unit 9 . This recording medium M records a discharge pressure evaluation program 97 that can be read by a computer (control unit 9). Examples of the recording medium M include a USB (Universal Serial Bus) memory, a memory card, or a memory device of an external server computer. In addition, the UI 95 has a display that displays information to the user and an input device that accepts the user's input operation. The control unit 9 having such a structure can be used in various computers such as desktop, laptop or tablet computers.

FIG. 4 is a flowchart showing an example of a discharge pressure evaluation method executed based on a discharge pressure evaluation program. In step S101 , the measurement execution unit 911 moves the actuating plate 816 according to the movement pattern specified by the discharge pressure evaluation program 97 , thereby causing the coating liquid to be discharged from the nozzle 71 (simulated discharge). In this way, in general, when the actuating disk portion 816 accelerates from speed zero to a predetermined target speed, it moves at a constant speed at the target speed, and then decelerates from the target speed to speed zero. However, as shown in Japanese Patent Application Laid-Open No. 2020-040046, the speed (parameter) of the actuating plate portion 816 is adjusted during a partial period after the speed of the actuating plate portion 816 reaches the maximum speed and stabilizes at the target speed. Adjust while setting the movement mode.

Specifically, the movement pattern of the actuating disk portion 816 is defined in the discharge pressure evaluation program 97 so that the discharge pressure changes in the following sequence: ・The discharge pressure increases from the initial pressure Pi to the target pressure Pt which is greater than the initial pressure Pi. ・The discharge pressure is stable at the target pressure Pt ・The discharge pressure decreases from the target pressure Pt to the initial pressure Pi

Furthermore, in step S101, the coating liquid is discharged from the nozzle 71 as the actuating plate part 816 moves. In parallel with this, the measurement execution part 911 periodically obtains the discharge measured by the pressure gauge 86 at a predetermined sampling cycle. Measured value of pressure. In this manner, during the discharge period Tt ( FIG. 5 ) when the coating liquid is discharged from the nozzle 71 , the measurement result of the discharge pressure given to the coating liquid is obtained and stored in the memory unit 93 as the discharge pressure measurement data 99 . The discharge pressure measurement data 99 represents 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 of the discharge pressure shown in the discharge pressure measurement data 99 based on predetermined evaluation items. As will be described later, this evaluation item is to extract a predetermined feature value from the time change of the discharge pressure shown in the discharge pressure measurement data 99 and evaluate the time change of the discharge pressure based on the feature value. Next, each evaluation item for evaluating the time change of the discharge pressure shown in the discharge pressure measurement data 99 will be described in detail.

FIG. 5 is a diagram illustrating each period used for evaluation of discharge pressure. In FIG. 5 , the horizontal axis represents time and the vertical axis represents discharge pressure. In this figure, the time change of the discharge pressure is schematically shown. Furthermore, the labels of the relevant figures are the same in each figure disclosed later. In the example of FIG. 5 , the discharge pressure measurement data 99 is obtained from before starting to discharge the coating liquid from the nozzle 71 to after finishing the discharge of the coating liquid from the nozzle 71 (that is, before and after the discharge period Tt). In this example, the discharge pressure at the time ta when the nozzle 71 starts discharging the coating liquid and the discharge pressure at the time te when the nozzle 71 ends discharging the coating liquid are the initial pressure Pi. However, the respective pressures at the beginning and end of discharging are not necessarily always consistent with the initial pressure Pi.

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

The rising period Ta is from the time ta when the coating liquid supply mechanism 8 starts to discharge the coating liquid from the nozzle 71 (that is, the time ta when the coating liquid supply mechanism 8 starts to move the actuating plate part 816) to the time tb when the discharge pressure reaches the target pressure Pt. period until. That is, at time ta, the coating liquid starts to be discharged from the nozzle 71, and the discharge pressure increases from the initial pressure Pi to the target pressure Pt during the period from time ta to time tb.

The transition period Tb is a period from time tb to time tc after passing through a predetermined vibration attenuation period. This vibration attenuation period is a period required for the time change of the discharge pressure to be stable, and is set by the user's input operation on the UI 95, for example, and is stored in the memory unit 93.

The stable period Tc is a period from time tc to time td when the coating liquid supply mechanism 8 starts reducing the discharge pressure (ie, time td when the coating liquid supply mechanism 8 starts decelerating the actuating disk portion 816 from the target speed). That is, the coating liquid supply mechanism 8 moves the actuating plate portion 816 at a constant speed from time tc to time td, and starts decelerating the actuating plate portion 816 at time td. Furthermore, during the stable period Tc, the discharge pressure is basically stabilized at the target pressure Pt. However, during the stable period Tc, the time change of the discharge pressure still contains slight vibrations, and the discharge pressure becomes larger or smaller than the target pressure Pt.

In addition, the transition period Tb and the stable period Tc constitute a constant voltage period Tbc. That is, the constant pressure period Tbc is a period from time tb to time td.

The falling period Td is a period from time td to time te when the coating liquid supply mechanism 8 ends discharging the coating liquid from the nozzle 71 (that is, time te when the coating liquid supply mechanism 8 stops the actuating plate part 816). That is, the discharge pressure decreases to the initial pressure Pi between time td and time te, and the discharge of the coating liquid from the nozzle 71 stops at time te.

FIG. 6 is a diagram schematically showing an example of calculation performed by the pressure evaluation unit with respect to temporal changes in discharge pressure. As shown in FIG. 6 , the pressure evaluation unit 913 differentiates the time change of the discharge pressure with time, thereby calculating the first differential D1 of the time change of the discharge pressure. Furthermore, the pressure evaluation unit 913 differentiates the first differential D1 of the time change of the discharge pressure with time, thereby calculating the second differential D2 of the time change of the discharge pressure. In addition, the pressure evaluation unit 913 calculates the mean absolute error MAE (Mean Absolute Error) and the root mean square error RMSE (Root Mean Square Error) based on the following equations: MAE (α, β) = (1/n)・(Σ |α-β| ) RMSE(α,β)=((1/n)・(Σ (α-β) ² )) ^1/2 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 characteristic amount Fv1. The evaluation item in Figure 7 is to evaluate the time change of the discharge pressure shown in the discharge pressure measurement data 99 based on the error (ideal trapezoidal absolute error) between the trapezoidal waveform and the discharge pressure measurement data 99. Among them, the trapezoidal waveform has The amplitude corresponds to the difference between the average discharge pressure during the stable period Tc (that is, the stable pressure Pm) and the initial pressure Pi.

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

Similarly, during the drop period Td, linear regression analysis is performed on the time change of the discharge pressure between the upper reference pressure and the lower reference pressure, and the drop regression straight line Lr_F is calculated. This drop regression line Lr_F linearly decreases from the stable pressure Pm to the initial pressure Pi between time t13 and time t14.

Furthermore, the lower reference pressure and the upper reference pressure are pressures that are larger than the initial pressure Pi and smaller than the target pressure Pt. They are set by the user's input operation on the UI 95, for example, and are memorized in the memory unit 93. . 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. The upper reference pressure is a pressure obtained by adding the initial pressure Pi and the target pressure Pt. The pressure obtained by adding 80% of the absolute value of the difference between Pt to the initial pressure Pi.

In addition, for the interval from time ta to time t11, an approximate straight line Lr_s is set at the beginning. The initial approximate straight line Lr_s is a straight line indicating that the slope of the initial pressure Pi is zero. That is, the initial approximate straight line Lr_s is a straight line connected from the time point (time ta) when the coating liquid is discharged from the nozzle 71 to the start time point of the rising regression line Lr_R. Furthermore, depending on the state (slope) of the regression line, time t11 may be earlier than time ta, and time t12 may be later than time tb. As a result, when t11<ta is satisfied, the initial approximation straight line Lr_s is omitted.

In addition, for the interval from time t14 to time te, the end approximation straight line Lr_e is set. The end-time approximate straight line Lr_e is a straight line indicating that the slope of the initial pressure Pi is zero. That is, the end-time approximate straight line Lr_e is a straight line connecting from the end time point of falling into the regression straight line Lr_F to the time point (time te) when the discharge of the coating liquid from the nozzle 71 is completed. Furthermore, when te<t14 is satisfied, the end-time approximation straight line Lr_e is omitted.

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

In this way, the approximate waveform WF1 composed of the starting approximate straight line Lr_s, the rising regression straight line Lr_R, the stable straight line Lr_m, the falling regression straight line Lr_F and the ending approximate straight line Lr_e arranged in time series is calculated. Next, the pressure evaluation unit 913 calculates the mean absolute error MAE (ideal trapezoidal absolute error) between the discharge pressure measurement data 99 and the approximate waveform WF1 in the entire discharge period Tt from time ta to time te as a feature quantity. Fv1. In addition, the pressure evaluation unit 913 normalizes the feature value Fv1 to a range of 0 or more and 2 or less based on a predetermined threshold value Th1 (for example, 0.05). Specifically, the feature quantity Fv1 is converted into the standardized feature quantity Fv1 (ie, the evaluation value V1) according to the following mathematical formula: If Fv1<Th1, then Fv1=0 If Fv1≧Th1, then Fv1=(Fv1+1-Th1)×c1 Here, the coefficient c1 is a standardized coefficient, which is set in advance to a value (for example, 15) in a range in which the feature value Fv1 converges to 2 or less.

According to the evaluation of the characteristic value Fv1 in FIG. 7 , when the time change of the discharge pressure in the entire discharge period Tt greatly deviates from the ideal shape (i.e., trapezoidal shape), a larger score (i.e., poorer) can be assigned to the discharge pressure. evaluation).

FIG. 8 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv2. The evaluation items in Figure 8 evaluate the smoothness of the increase in discharge pressure. Specifically, during the rise period Ta, a curve regression analysis is performed on the time change in the discharge pressure between the lower reference pressure P2_l and the upper reference pressure P2_u which is greater than the lower reference pressure P2_l, and the rise regression is calculated Curve Nr. The curve regression analysis is performed using a quadratic curve.

The lower reference pressure P2_1 is set as the initial pressure Pi. On the other hand, the upper reference pressure P2_u is a pressure that is greater than the lower reference pressure P2_l and smaller than the target pressure Pt. It is set by the user's input operation on the UI 95 and is stored in the memory unit 93, for example. 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. This 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. Furthermore, time t21 coincides with time ta, and time t22 is a time after time ta and before time tb.

In this way, the waveform WF2 composed of the rising regression curve Nr is calculated. Next, the pressure evaluation unit 913 calculates the root mean square error RMSE between the output pressure measurement data 99 and the waveform WF2 in the initial rise period Ta_s from time t21 to time t22 as the feature amount Fv2. In addition, the pressure evaluation unit 913 normalizes the feature value Fv2 to a range of 0 or more and 2 or less based on a predetermined threshold value Th2 (for example, 0.05). Specifically, the feature quantity Fv2 is converted into the standardized feature quantity Fv2 (ie, the evaluation value V2) according to the following mathematical formula: If Fv2<Th2, then Fv2=0 If Fv2≧Th2, then Fv2=2

For example, based on the evaluation of the characteristic value Fv2 in FIG. 8 , when the state before starting to discharge the coating liquid from the nozzle 71 is affected and the discharge pressure immediately after the start of discharge is abnormal, a large score can be given to the discharge pressure ( that is, a poor evaluation). Furthermore, the curves that can be used for curve regression analysis are not limited to quadratic curves, and can also be other curves such as exponential functions.

FIG. 9 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv3. The evaluation items in Figure 9 evaluate whether the rising period Ta converges within a certain period. Specifically, the pressure evaluation unit 913 calculates the length of the rising period Ta from time ta to time tb (=tb-ta) required for the discharge pressure to increase from the initial pressure Pi toward the target pressure Pt as a characteristic amount. Fv3. In addition, the pressure evaluation unit 913 normalizes the feature value Fv3 to a range of 0 or more and 1 or less based on a predetermined threshold value Th3 (for example, 350 ms). Specifically, the feature quantity Fv3 is converted into the standardized feature quantity Fv3 (ie, the evaluation value V3) according to the following mathematical formula: If Fv3<Th3, then Fv3=0 If Fv3≧Th3, then Fv3=1

For example, based on the evaluation of the feature value Fv3 in FIG. 9 , a larger score (that is, a poor evaluation) can be given to the discharge pressure that takes time to rise to the target pressure Pt.

FIG. 10A is a diagram illustrating evaluation items for evaluating the temporal change of the discharge pressure based on the characteristic amount Fv4. FIG. 10B is a diagram showing an example of the temporal variation of the discharge pressure determined to be inappropriate based on the evaluation based on the characteristic amount Fv4. . The evaluation item in Fig. 10A evaluates whether there is any abnormality in the increase in discharge pressure. Specifically, the pressure evaluation unit 913 calculates the first differential D1 of the time change of the discharge pressure for the rising period Ta from time ta to time tb, and obtains the first differential waveform WF4.

Next, the pressure evaluation unit 913 determines the number of times the primary differential waveform WF4 crosses the predetermined threshold value Th4 during the rising period Ta as the characteristic amount Fv4. In the example of FIG. 10A , the primary differential waveform WF4 and the threshold value Th4 (for example, 0.002) cross each other at time t41 and time t42, and the number of crossings (feature amount Fv4) is two. In addition, the stress evaluation unit 913 normalizes the feature value Fv4 to a range of 0 or more and 1 or less. Specifically, the feature quantity Fv4 is converted into the standardized feature quantity Fv4 (ie, the evaluation value V4) according to the following mathematical formula: If Fv4≦2, then Fv4=0 If Fv4>2, then Fv4=1

Based on the evaluation of the characteristic amount Fv4 in FIG. 10A , when a step occurs in the time change of the discharge pressure during the rising period Ta (for example, as shown in FIG. 10B ), a larger score (that is, a poor evaluation) can be given to the discharge pressure. .

FIG. 11A is a diagram illustrating evaluation items for evaluating the temporal change of the discharge pressure based on the characteristic amount Fv5. FIG. 11B is a diagram showing an example of the temporal variation of the discharge pressure determined to be inappropriate based on the evaluation based on the characteristic amount Fv5. . The evaluation item in Figure 11A evaluates whether there is any abnormality in the increase in discharge pressure. Specifically, the pressure evaluation unit 913 calculates the second-order differential D2 of the time change of the discharge pressure for the rising period Ta from time ta to time tb, and obtains the second-order differential waveform WF5.

Next, the pressure evaluation unit 913 determines the number of times the absolute value of the second-order differential waveform WF5 crosses the predetermined threshold value Th5 during the rising period Ta as the characteristic amount Fv5. In the example of FIG. 11A , the absolute value of the second-order differential waveform WF5 intersects with the threshold value Th5 (for example, 0.0002) at each of times t51, t52, t53, and t54, and the number of intersections (feature amount Fv5) is four. In addition, the stress evaluation unit 913 normalizes the feature value Fv5 to a range of 0 or more and 1 or less. Specifically, the feature quantity Fv5 is converted into the standardized feature quantity Fv5 (ie, the evaluation value V5) according to the following mathematical formula: If Fv5=4, then Fv5=0 If Fv5≠4, then Fv5=1

Based on the evaluation of the characteristic amount Fv5 in FIG. 11A , when a step occurs in the time change of the discharge pressure during the rising period Ta (for example, as shown in FIG. 11B ), a larger score (that is, a poor evaluation) can be given to the discharge pressure. .

FIG. 12 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv6. The evaluation items in Figure 12 evaluate whether the increase in discharge pressure does not stall in the second half. Specifically, the pressure evaluation unit 913 calculates the second-order differential D2 of the time change of the discharge pressure for the rising period Ta from time ta to time tb, and obtains the second-order differential waveform WF6.

Next, the pressure evaluation unit 913 calculates the time T_1st when the second-order differential waveform WF6 becomes larger than the predetermined positive threshold value (Th5) and the second-order differential waveform WF6 when it becomes larger than the predetermined positive threshold value (Th5) during the rising period Ta. The negative threshold value (-Th5) is the smaller time T_2nd. Here, the positive threshold value and the negative threshold value have the same absolute value (Th5) and have different signs. The absolute values (Th5) of the positive threshold value and the negative threshold value are equal to the absolute value of the threshold value Th5 used in the evaluation of the feature quantity Fv5. Next, the pressure evaluation unit 913 obtains the ratio of these times (=T_1st/T_2nd) as the feature amount Fv6. Furthermore, the pressure evaluation unit 913 converts the feature amount Fv6 according to the following equation: Fv6=|1-Fv6|

In addition, the pressure evaluation unit 913 normalizes the thus converted feature amount Fv6 to a range of 0 or more and 2 or less using a predetermined threshold value Th6 (for example, 0.2). Specifically, the feature quantity Fv6 is converted into the standardized feature quantity Fv6 (ie, the evaluation value V6) according to the following mathematical formula: If Fv6<Th6, then Fv6=0 If Fv6≧Th6, then Fv6=f(Fv6) f(γ)=4×γ-0.8 In addition, the function f(γ) using γ as a variable is not limited to this example, and it can be changed arbitrarily.

The conveyance speed of the substrate S to be coated with the coating liquid is a target speed that is reached without stalling even in the second half of the acceleration period. Therefore, it is preferable that the discharge pressure given to the coating liquid reaches the target pressure Pt without stalling during the rising period Ta. On the other hand, according to the evaluation of the characteristic amount Fv6 in FIG. 12 , when the discharge pressure stalls during the rising period Ta, a large score (that is, a poor evaluation) can be given to the discharge pressure.

FIG. 13 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv7. The evaluation items in Figure 13 evaluate the sharpness of the time change of the discharge pressure at the end of the rise. Specifically, linear regression analysis is performed on the time change of the discharge pressure 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, and the rising end period is calculated Regression straight line Lr. 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 a pressure obtained by adding the initial pressure Pi and the target pressure Pt The discharge pressure is the pressure obtained by adding 90% of the absolute value of the difference to the initial pressure Pi. The discharge pressure increases from the lower reference pressure P7_l toward the upper reference pressure P7_u between time t71 and time t72.

This rise-end regression line Lr increases as time passes, and reaches the stable pressure Pm (the average value of the discharge pressure during the stable period Tc) at time t73. In this way, the rising terminal regression straight line Lr is set for the interval from time t71 to time t73. Furthermore, the pressure evaluation unit 913 sets an extended straight line Lm with a slope of zero indicating the stable pressure Pm between time t73 and time tb. As mentioned above, time tb is the time when the discharge pressure reaches the target pressure Pt, which corresponds to the end time of the rising period Ta. That is, the extended straight line Lm is set to extend from (the end time point of) the rise final regression straight line Lr to the end time point of the rise period Ta. In addition, when tb<t73, the extended straight line Lm is omitted.

In this way, the approximate waveform WF7 composed of the rising terminal regression straight line Lr and the extension straight line Lm is arranged in time series is calculated. Next, the pressure evaluation unit 913 calculates, in the rising end 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%, the distance between the discharge pressure measurement data 99 and the approximate waveform WF7 The difference value is taken as the feature quantity Fv7. Specifically, the weighted reference time width Tw=t73-t72 is set. Then, calculate the sum of additional weighted root mean square errors according to the following equation: Fv7=(Σ(P_measure-WF7) ² ×W) ^1/2 P_measure=Discharge pressure measurement data 99 At time tb≦t73+2×Tw Range, W=1 In the range of time tb>t73+2×Tw, W=w w is a weight coefficient larger than 1, such as 10

In addition, the pressure evaluation unit 913 normalizes the feature value Fv7 to a range of 0 or more and 2 or less based on a predetermined threshold value Th7 (for example, 0.6). Specifically, the feature quantity Fv7 is converted into the standardized feature quantity Fv7 (ie, the evaluation value V7) according to the following mathematical formula: If Fv7<Th7, then Fv7=0 If Fv7≧Th7, then Fv7=Fv7/c7 c7 is any positive constant, such as 1.1

For example, according to the evaluation of the characteristic quantity Fv7 in Figure 13, when the rising momentum is weak and the time change of the discharge pressure shows a waveform with rounded corners, a larger score (ie, a poor evaluation) can be assigned to the discharge pressure. .

FIG. 14 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv8. The evaluation items in Figure 14 evaluate the degree of overshoot that occurs when the discharge pressure increases. 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. Next, the pressure evaluation unit 913 calculates time t82 when the sign of the second derivative D2 of the discharge pressure switches twice from the sign at time t81. Next, the time change of the discharge pressure in 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 in the initial vibration period Tb_s is found, and the smaller of the stable pressure Pm and the pressure P8min is selected as the target pressure Pg. Next, the characteristic amount Fv8 is calculated based on the difference between the maximum pressure Pmax and the target pressure Pg, that is, the following equation: Fv8=Pmax-Pg

Furthermore, the pressure evaluation unit 913 normalizes the feature value Fv8 to a range of 0 or more and 2 or less using a predetermined threshold value Th8 (for example, 0.035). Specifically, the feature quantity Fv8 is converted into the standardized feature quantity Fv8 (ie, the evaluation value V8) according to the following formula: If Fv8<Th8, then Fv8=0 If Fv8≧Th8, then Fv8=Fv8/c8 c8 is any positive constant, such as 0.12

According to the evaluation of the characteristic quantity Fv8 in Figure 14, when the rising momentum is strong and the time change of the discharge pressure shows a large overshoot, a large score (ie, poor score) can be assigned to the discharge pressure. evaluation).

FIG. 15 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv9. The evaluation items in Fig. 15 evaluate the stability of the time change of the discharge pressure in Tb during the migration period. Specifically, the pressure evaluation unit 913 calculates the root mean square error RMSE (P_measure, Pm) based on the following equation based on the stable pressure Pm, which is the average value of the discharge pressure in the transition period Tb and the discharge pressure in the stable period Tc. ), and as the feature quantity Fv9: Fv9=RMSE(P_measure,Pm) P_measure=Spit out pressure measurement data 99

Furthermore, the stress evaluation unit 913 normalizes the feature value Fv9 to a range of 0 or more and 2 or less. Specifically, the feature quantity Fv9 is converted into the standardized feature quantity Fv9 (ie, the evaluation value V9) according to the following mathematical formula: Fv9=Fv9/c9 c9 is any positive constant, such as 0.04

According to the evaluation of the characteristic amount Fv9 in FIG. 15 , when the time change of the discharge pressure shows ringing in the transition period Tb, a large score (ie, a poor evaluation) can be given to the discharge pressure.

FIG. 16 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv10. The evaluation items in Figure 16 evaluate the stability of the time change of the discharge pressure in Tbc during the constant pressure period. 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. Next, the pressure evaluation unit 913 calculates the characteristic amount Fv10 based on the difference between the maximum pressure Pmax and the minimum pressure P10min in the constant pressure period Tbc, that is, based on the following equation: Fv10=Pmax-P10min

Furthermore, the pressure evaluation unit 913 normalizes the feature value Fv10 to a range of 0 or more and 2 or less using the threshold value Th10 (for example, 0.12). Specifically, the feature quantity Fv10 is converted into the standardized feature quantity Fv10 (ie, the evaluation value V10) according to the following mathematical formula: If Fv10<Th10, then Fv10=0 If Fv10≧Th10, then Fv10=Fv10/Th10

According to the evaluation of the characteristic quantity Fv10 in Figure 16, when the time change of the discharge pressure shows a large difference in the stable period Tc which has a large influence on the film thickness of the coating liquid, a large score can be assigned to the discharge pressure (i.e., poor rating).

In this way, the pressure evaluation unit 913 calculates the evaluation values V1 to V10 based on the result of extracting each of the feature values Fv1 to Fv10 from the discharge pressure measurement data 99 . Next, the pressure evaluation unit 913 calculates the total of the evaluation values V1 to V10 as the final evaluation value for the time change of the discharge pressure shown in the discharge pressure measurement data 99 (step S102).

In the above-described embodiment, the discharge pressure is measured during the discharge period Tt (first period, evaluation target period) from when the nozzle 71 starts discharging the coating liquid (processing liquid) to when the nozzle 71 ends discharging the coating liquid (the first period, the evaluation target period) (step S101 ). Next, the ideal trapezoidal absolute error of the time change of the discharge pressure in the entire discharge period Tt is extracted as a feature value Fv1 (first feature value, overall feature value), and the time change of the discharge pressure is calculated based on this feature value Fv1 Evaluation is performed (step S102). Thereby, the adequacy of the discharge pressure in the entire discharge period Tt from the start of discharge of the coating liquid to the end of discharge from the nozzle 71 can be reflected in the evaluation of the discharge pressure.

In addition, as shown in FIG. 7 , the characteristic amount Fv1 represents the difference between an approximate waveform WF1 (first approximate waveform) that approximates the time change of the discharge pressure in the entire discharge period Tt, and the time change of the discharge pressure in the entire discharge period Tt. . In this configuration, the discharge pressure in the entire discharge period Tt can be appropriately evaluated based on the approximate waveform WF1 corresponding to the time change of the discharge pressure in the entire discharge period Tt from when the nozzle 71 starts to discharge the coating liquid to the end. .

In particular, the approximate waveform WF1 system has: ・The rising regression straight line Lr_R (rising approximate straight line) is a straight line that approximates the time change of the discharge pressure that increases with the passage of time after the nozzle 71 starts to discharge the coating liquid. Thereby, from the initial pressure Pi (the discharge start pressure) It increases linearly with the passage of time from the stable pressure Pm which is greater than the initial pressure Pi; ・The initial approximate straight line Lr_s is set between the starting time point (time ta) when the coating liquid is discharged from the nozzle 71 and the rising regression line Lr_R to represent the initial pressure Pi; ・The drop regression line Lr_F (drop approximation straight line) is a straight line that approximates the time change of the discharge pressure that decreases with the passage of time until the coating liquid is discharged from the nozzle 71, thereby changing from the stable pressure Pm to the more stable pressure Pm It decreases linearly with the passage of time until it reaches a small initial pressure Pi (discharge end pressure); ・The end approximate straight line Lr_e is set between the drop regression line Lr_F and the end time point (time te) of discharging the coating liquid from the nozzle 71, and represents the initial pressure Pi (discharge end pressure); and ・The stable straight line Lr_m connects the rising regression straight line Lr_R and the falling regression straight line Lr_F to represent the stable pressure Pm. In this configuration, the time change of the discharge pressure in the entire discharge period Tt from the beginning to the end of the discharge of the coating liquid from the nozzle 71 is made more similar to a trapezoidal waveform, and the discharge pressure in the entire discharge period Tt can be appropriately evaluated. .

In addition, the characteristic amounts Fv2 to Fv10 (second characteristic amounts) of the time change of the discharge pressure in the period (second period) that is shorter than the discharge period Tt in the discharge period Tt are extracted, and based on the characteristic amounts Fv2 to Fv10, The time change of the discharge pressure is evaluated (step S102). In this configuration, the discharge pressure can be adjusted with high accuracy based on the temporal changes in the discharge pressure during both the entire discharge period Tt from the start to the end of discharge of the coating liquid from the nozzle 71 and the period shorter than the discharge period Tt. Make an evaluation.

In addition, among the evaluation items shown in FIG. 8 , the discharge pressure in the predetermined rising initial period Ta_s (second period) from the start of discharge of the coating liquid from the nozzle 71 is evaluated. Throughout the initial rise period Ta_s, the discharge pressure increases with the passage of time. The difference between the rise regression curve Nr of the time change of the discharge pressure in the rise initial period Ta_s and the time change of the discharge pressure in the rise initial period Ta_s is, The feature quantity Fv2 (second feature quantity) representing this difference is extracted. In this configuration, the discharge pressure can be evaluated by adding the temporal change in the discharge pressure immediately after the nozzle 71 starts discharging the coating liquid.

In addition, the discharge pressure in the rising period Ta (second period) from the start of discharge of the coating liquid from the nozzle 71 until the discharge pressure increases to the target pressure Pt (predetermined pressure) is evaluated. In this configuration, the discharge pressure can be evaluated by adding the time change of the discharge pressure during the rising period Ta.

Specifically, among the evaluation items shown in FIG. 9 , the length of the rising period Ta is extracted as the feature amount Fv2 (second feature amount). In this configuration, the discharge pressure can be evaluated by adding the rise rate of the discharge pressure.

In addition, among the evaluation items shown in FIGS. 10A and 10B , the number of times that the first differential D1 of the time change of the discharge pressure during the rising period Ta crosses the predetermined threshold value Th4 is extracted as the feature value Fv4 (second characteristic quantity). In this configuration, the smoothness of the temporal change of the discharge pressure during the rising period can be added to evaluate the discharge pressure.

In addition, among the evaluation items shown in Fig. 11, the number of times the absolute value of the second derivative D2 of the time change of the discharge pressure crosses the predetermined threshold value Th5 during the rising period Ta is extracted as the characteristic amount Fv5 ( second characteristic quantity). In this configuration, the smoothness of the temporal change of the discharge pressure in the rising period Ta can be added to evaluate the discharge pressure.

In addition, in the evaluation items shown in Figure 12, for the time T_1st when the second derivative D2 of the time change of the discharge pressure becomes larger than the predetermined positive threshold value (Th5) during the rising period Ta, and the time T_1st of the discharge pressure The ratio of the time T_2nd at which the quadratic differential D2 of the time change becomes smaller than the negative threshold value (-Th5) having the same absolute value as the positive threshold value is extracted as the feature amount Fv6 (second characteristic quantity). In this configuration, the discharge pressure can be evaluated by adding the difference in the time change of the discharge pressure at the initial and final stages of the rise period Ta.

In addition, among the evaluation items shown in FIG. 13 , the discharge pressure in the rising final period Ta_e (second period) until the discharge pressure increases to the target pressure Pt (predetermined pressure) is evaluated. That is, for the difference between the approximate waveform WF7 (approximate waveform at the end of rise) that approximates the time change of the discharge pressure in the end of rise period Ta_e, and the time change of the discharge pressure in the end of rise period Ta_e, the characteristic amount Fv7 representing the difference is extracted (the second characteristic quantity). This approximate waveform WF7 is composed of a rise-end regression straight line Lr (rise-end approximation straight line) and an extension straight line Lm. The regression line Lr at the end of the rise is a straight line approximation to the time change of the discharge pressure that increases with the passage of time in a pressure range (P7_l~P7_u) smaller than the target pressure Pt, and overlaps with the obtained approximate curve. As time passes, it increases linearly until it reaches the stable pressure Pm. The extended straight line Lm extends from (the end time point of) the rising terminal regression line Lr to the ending time point of the rising terminal period Ta_e, and represents the stable pressure Pm. In this configuration, the discharge pressure can be evaluated by adding the stall degree of the discharge pressure at the end of the rising period Ta.

In addition, in the evaluation items shown in Figure 14, from the time point when the discharge pressure reaches the maximum value Pmax (time t81) to the time point when the second derivative D2 of the time change of the discharge pressure crosses zero twice (time t81) The discharge pressure in the initial vibration period Tb_s (second period) up to t82) 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 of the minimum value P8min and the stable pressure Pm and the maximum value Pmax of the discharge pressure is extracted as Feature amount Fv8 (second feature amount). In this configuration, the discharge pressure can be evaluated by adding an overshoot of the discharge pressure.

In addition, in the evaluation items shown in FIG. 15 , the discharge pressure in the predetermined transition period Tb (second period) from the time point (time tb) when the discharge pressure exceeds the target pressure Pt (predetermined pressure) is evaluated. Specifically, a feature value Fv9 (second feature value) representing the difference between the discharge pressure and the stable pressure Pm during the rising period Ta is extracted. In this configuration, the discharge pressure can be evaluated by adding the stability of the discharge pressure after the discharge pressure reaches the target pressure Pt.

In addition, in the evaluation items shown in FIG. 16 , the time from the time point (time tb) when the discharge pressure exceeds the target pressure Pt (predetermined pressure) to the end of discharge of the coating liquid from the nozzle 71 and the time when the discharge pressure starts to decrease is The discharge pressure in the constant pressure period Tbc up to the point (time td) is evaluated. Specifically, the feature quantity Fv10 representing the difference between the maximum value Pmax and the minimum value P10min of the discharge pressure in the constant pressure period Tbc is extracted. In this configuration, the discharge pressure can be evaluated by adding the stability of the discharge pressure during the constant pressure period Tbc.

As described above, in the above embodiment, the coating device 1 corresponds to an example of the "substrate processing apparatus" 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 As an example of the "pressure imparting part" of the present invention, the nozzle 71 and the coating liquid supply mechanism 8 cooperate to form an example of the "discharge device" of the present invention. The pressure gauge 86 is equivalent to an example of the "measuring part" of the present invention. Control The unit 9 corresponds to an example of the "computer" and the "control unit" 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 "recording medium" of the present invention. As an example, the coating liquid corresponds to an example of the "processing liquid" of the present invention, and the pressure measured by the pressure gauge 86 corresponds to an example of the "discharge pressure" of the present invention.

In addition, the discharge period Tt is equivalent to an example of the "first period" of the present invention, the characteristic quantity Fv1 is equivalent to an example of the "first characteristic quantity" of the present invention, and the approximate waveform WF1 is equivalent to the "first approximation" of the present invention. The initial pressure Pi is an example of the "discharge start pressure" and the "discharge end pressure" of the present invention, and the rising regression line Lr_R is an example of the "rising approximate straight line" of the present invention, which is an approximate straight line at the beginning. Lr_s is equivalent to an example of the "starting approximate straight line" of the present invention, the falling regression straight line Lr_F is equivalent to an example of the "falling approximate straight line" of the present invention, and the ending approximate straight line Lr_e is equivalent to the "ending approximate straight line" of the present invention. ”, the stable straight line Lr_m is equivalent to an example of the “stable straight line” in the present invention.

Furthermore, the initial rise period Ta_s, the rise period Ta, the final rise period Ta_e, the initial vibration period Tb_s, the transition period Tb, and the constant pressure period Tbc are equivalent to an example of the "second period" of the present invention, and the characteristic amounts Fv2 to Fv10 are equivalent to each other. As an example of the "second characteristic quantity" of the present invention, the initial period Ta_s is equivalent to an example of the "initial rising period" of the present invention, the regression curve Nr is equivalent to an example of the "regression curve" of the present invention, and the rising period Ta is The rising terminal period Ta_e is equivalent to an example of the "rising period" of the present invention. The rising terminal period Ta_e is equivalent to an example of the "rising terminal period" of the present invention. The approximate waveform WF7 is equivalent to an example of the "rising terminal approximate waveform" of the present invention. The rising terminal period The regression straight line Lr is equivalent to an example of the "rising end approximation straight line" of the present invention, the extension straight line Lm is equivalent to an example of the "extended straight line" of the present invention, and the initial vibration period Tb_s is equivalent to the "initial vibration period" of the present invention. For example, the stable period Tc is equivalent to an example of the "stable period" of the present invention, the transition period Tb is equivalent to an example of the "transition period" of the present invention, and the constant pressure period Tbc is equivalent to one of the "constant pressure periods" of the present invention. An example.

In addition, this invention is not limited to the above-mentioned embodiment, As long as it does not deviate from the summary, various changes other than the above-mentioned embodiment can be made. For example, in the above embodiment, the discharge characteristics are measured based on the pressure value detected by the pressure gauge 86 installed in the pipe 82. However, the installation position of the pressure gauge 86 is not limited to this, as long as it can be measured. The installation position can be any position where the pressure of the coating liquid supplied to the nozzle 71 is detected.

In addition, in the above embodiment, the bellows type pump 81 is used, but the type of the pump is not limited thereto. For example, a syringe type pump may also be used (for example, Japanese Patent Laid-Open No. 2008-101510). System uses piston.

In addition, in the above-mentioned embodiment, although the present invention is applied to the coating device 1 that supplies the coating liquid to the surface Sf of the substrate S in a state where the substrate S is floated, the applicable objects of the present invention are not limited thereto. , the present invention can be applied to all substrate processing technologies that perform a predetermined process by transporting a processing liquid to a nozzle and supplying the processing liquid from the nozzle to the upper surface of the substrate.

In addition, the present invention does not need to evaluate the discharge pressure based on all the above-mentioned characteristic values Fv2 to Fv10. It may also be configured to evaluate the discharge pressure based on only a part of these characteristic values. Alternatively, the discharge pressure may be evaluated based only on the characteristic value Fv1.

In addition, when calculating the approximate waveform WF1 in FIG. 7 , a straight line with a slope of zero representing the target pressure Pt can also be used instead of the stable straight line Lr_m.

Furthermore, the characteristic value Fv1_1 described in the following modifications may be calculated instead of the characteristic value Fv1 shown in FIG. 7 , and the time change of the discharge pressure may be evaluated based on the characteristic value Fv1_1. FIG. 17 is a diagram illustrating each period used in a modified example of the evaluation item of discharge pressure, and FIG. 18 is a diagram illustrating a modified example of the evaluation item that evaluates the time change of the discharge pressure based on the characteristic amount Fv1_1. . Here, the description will be mainly focused on the differences between FIG. 17 and the above-mentioned FIG. 5 , and the common points between these drawings will be given equal symbols and their description will be appropriately omitted. Similarly, the description will be mainly focused on the differences between FIG. 18 and FIG. 7 , and the common points between these drawings will be given equal symbols and the description will be omitted appropriately.

As shown in FIG. 17 , in a modification of the evaluation item, the attention period Troi is used. The attention period Troi is the period from time ta to time td. That is, the attention period Troi is composed of the rising period Ta, the transition period Tb, and the stable period Tc. In other words, it is composed of the rising period Ta and the constant pressure period Tbc. In this way, the period of interest Troi is equivalent to an example of "the main period is the period from when the processing liquid starts to be discharged from the nozzle, after the discharge pressure rises to the predetermined pressure, to when the discharge pressure starts to decrease from the predetermined pressure" in the present invention, the target pressure Pt This is an example of "predetermined pressure" equivalent to the present invention.

As shown in FIG. 18 , in this modified example, similarly to the case of the above-mentioned feature value Fv1, a starting approximate straight line Lr_s is set together with the calculation of the ascending regression straight line Lr_R. Furthermore, between time t12 and time td, a straight line representing the stable pressure Pm (that is, the average of the measured values of the discharge pressure during the stable period Tc) with a slope of zero, that is, a stable straight line Lr_m_1, is set.

In this way, the approximate waveform WF1_1 composed of the initial approximate straight line Lr_s, the rising regression straight line Lr_R and the stable straight line Lr_m_1 arranged in time series is calculated. Next, the pressure evaluation unit 913 calculates the mean absolute error MAE between the output pressure measurement data 99 and the approximate waveform WF1_1 in the entire attention period Troi from time ta to time td as the feature amount Fv1_1. In addition, the pressure evaluation unit 913 normalizes the feature value Fv1_1 into a predetermined range based on a predetermined threshold value Th1_1 (for example, 0.05). Specifically, the feature quantity Fv1_1 is converted into the standardized feature quantity Fv1_1 (ie, the evaluation value V1_1) according to the following mathematical formula: If Fv1_1<Th1_1, then Fv1_1=0 If Fv1_1≧Th1_1, then Fv1_1=(Fv1_1+1-Th1_1)×c1_1 Here, the upper limit of Fv1_1 is set to 2×c1_1, and the coefficient c1_1 is a standardized coefficient, that is, an arbitrary positive constant. In addition, the specific method of normalizing the feature quantity Fv1_1 is not limited to this example, and can be changed appropriately.

As evaluated based on the feature quantity Fv1_1 in FIG. 18 , if the time variation of the discharge pressure in the entire Troi during the attention period greatly deviates from the ideal shape, a large score (that is, a poor evaluation) can be given to the discharge pressure.

In this modification, in the measurement result evaluation (step S102) of the discharge pressure evaluation shown in FIG. 4, the pressure evaluation unit 913 does not extract the feature value Fv1 based on the self-discharge pressure, but extracts the feature value based on the self-discharge pressure. The result of Fv1_1 is used to calculate the evaluation value V1_1. Furthermore, similarly to the above, the pressure evaluation unit 913 calculates the evaluation values V2 to V10 based on the result of extracting the feature values Fv2 to Fv10 from the discharge pressure. Next, the pressure evaluation unit 913 obtains the total of the evaluation values V1_1, V2 to V10 as the final evaluation value for the time change of the discharge pressure shown in the discharge pressure measurement data 99 (step S102).

In the modified example described above, the attention period Troi (main period, after the discharge pressure starts to rise to the target pressure Pt (predetermined pressure) from the time when the discharge pressure starts to be discharged from the nozzle 71 until the discharge pressure starts to decrease from the target pressure Pt) During the evaluation target period), the discharge pressure is measured. Next, the characteristic amount Fv1_1 (overall characteristic amount) of the temporal change in the discharge pressure in the entire attention period Troi is extracted, and the temporal change in the discharge pressure is evaluated based on the characteristic amount Fv1_1. Thereby, the appropriateness of the discharge pressure in the entire attention period Troi, which affects the thickness of the processing liquid applied to the substrate S, can be reflected in the evaluation of the discharge pressure.

Furthermore, in this modification, when the influence of the attention period Troi on the thickness of the processing liquid applied to the substrate S is particularly large (in other words, when the influence of the period after the attention period Troi is only slight), the effect of the attention period Troi can be made The adequacy of the discharge pressure in the entire Troi during the attention period is reflected in the evaluation of the discharge pressure.

In addition, the feature amount Fv1_1 (main feature amount) represents an approximate waveform WF1_1 (main approximation waveform) that approximates the time change of the discharge pressure in the entire attention period Troi (the main period), and the time change of the discharge pressure in the entire attention period Troi. Difference. In this configuration, the discharge pressure in the entire attention period Troi can be appropriately evaluated based on the approximate waveform WF1_1 of the time change of the discharge pressure in the entire attention period Troi.

In particular, the approximate waveform WF1_1 has: ・The rising regression line Lr_R (rising approximate straight line) increases linearly with the passage of time from the initial pressure Pi (discharge start pressure) to the stable pressure Pm which is greater than the initial pressure Pi. It is a straight line approximation to The time change of the discharge pressure that increases with the passage of time after starting to discharge the coating liquid from the nozzle 71; ・The initial approximate straight line Lr_s is set between the start time point (time ta) of discharging the coating liquid from the nozzle 71 and the rising regression line Lr_R, and represents the initial pressure Pi; and ・The stable straight line Lr_m_1 is set between the time when the rising regression line Lr_R reaches the stable pressure Pm and the end of the attention period Troi (between time t12 and time td), and represents the stable pressure Pm. In this configuration, the discharge pressure in the entire attention period Troi can be appropriately evaluated by approximating the time change of the discharge pressure in the entire attention period Troi.

Incidentally, when the discharge pressure is evaluated using the characteristic amount Fv1_1 shown in FIG. 18, in step S101, it is not necessary to measure the discharge pressure during the period after the attention period Troi (that is, the drop period Td).

Furthermore, it may be configured so that the UI 95 can select which feature value is used to evaluate the discharge pressure among the two feature values Fv1 and Fv1_1 described above. At this time, in step S102, one of the feature value Fv1 and the feature value Fv1_1 is selected by the user's input operation on the UI 95, and the discharge pressure is evaluated using the feature value.

The present invention can be applied to the entire substrate processing technology in which the processing liquid is delivered to a nozzle and the processing liquid is ejected from the nozzle to the substrate with target characteristics and supplied.

1: Coating device (substrate processing device) 2: Input transfer part 3: Floating platform part 4:Output transfer part

5:Substrate transport department

7: Coating mechanism

8: Coating liquid supply mechanism (pressure imparting part)

9: Control unit (computer, control department)

21:Roller conveyor

22: Rotation and lifting drive mechanism

31: Entrance floating platform

32: Coating platform

33: Exit floating platform

34: Lift pin driving mechanism

35: Floating control mechanism

36:Lifting drive mechanism

41:Roller conveyor

42: Rotation and lifting drive mechanism

51:Chuck mechanism

52: Adsorption and migration control mechanism

61, 62: Sensor

71:Nozzle

72: Nozzle cleaning standby unit

81:Pump

82:Piping

83: Coating fluid replenishment unit

84:Piping 85:Open and close valve 86: Pressure gauge (measurement department) 91:Operation Department 93:Memory department 95:UI 97: Spit out the stress evaluation program 99:Spit out pressure measurement data 100:Input conveyor 101:Roller conveyor 102: Rotary drive mechanism 110:Output conveyor 111:Roller conveyor 112: Rotary drive mechanism 721:Roller 722:Cleaning Department 723:Roller groove 811:Flexible tube 812: Bellows 813:Small bellows department 814:Large corrugated pipe department 815:Pump room 816: Actuator plate 817:Drive Department 831:Storage box 833:Open and close valve 911:Measurement Execution Department 913: Stress Assessment Department D1: first differential D2: Second differential Fv1: Feature quantity (first feature quantity) Fv2~Fv10: Feature quantity (second feature quantity) Lm: extended straight line Lr: Regression straight line at the end of the rise (approximate straight line at the end of the rise) Lr_F: falling regression line Lr_R: Rising regression straight line (rising approximate straight line) Lr_e: Approximate straight line at the end Lr_m, Lr_m_1: stable straight line Lr_s: approximate straight line at the beginning M: recording medium Nr: rising regression curve (regression curve) Pi: initial pressure (discharge start pressure, discharge end pressure) Pm: stable pressure Pmax: maximum pressure (maximum value) Pt: target pressure P2_l, P7_l: Lower side reference pressure (lower side reference value) P2_u, P7_u: Upper reference pressure (upper reference value) P8min: pressure (minimum value) P10min: minimum pressure (minimum value) S:Substrate Sb: lower surface Sf: upper surface (surface) Ta: rising period (second period) Ta_e: rising final period (second period) Ta_s: Early rising period (second period) Tb: migration period (second period) Tbc: Constant pressure period (second period) Tb_s: Initial vibration period (second period) Tc: stable period Td: falling period Th4, Th5: threshold value Troi: period of attention Tt: Discharge period (first period) Tw: weight base time width T_1st, T_2nd: time ta, tb, tc, td, te: time t11, t12, t13, t14, t21, t22, t41, t42, t51, t52, t53, t54, t71, t72, t73, t81, t82: time WF1: Approximate waveform (first approximate waveform) WF2: Waveform WF4: First differential waveform WF5, WF6: Secondary differential waveform WF7: Approximate waveform (approximate waveform at the end of rising period) WF1_1: Approximate waveform (main approximate waveform) X, Dt: conveying direction Y: horizontal direction Z: vertical direction

FIG. 1 is a schematic diagram showing the overall structure of a coating device, which is one embodiment of the substrate processing device of the present invention. Fig. 2 is a structural diagram showing a coating liquid supply mechanism. FIG. 3 is a block diagram showing an example of the structure 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. 5 is a diagram illustrating each period used for evaluation of discharge pressure. FIG. 6 is a diagram schematically showing an example of calculation performed by the pressure evaluation unit with respect to temporal changes in discharge pressure. FIG. 7 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv1. FIG. 8 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv2. FIG. 9 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv3. FIG. 10A is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv4. FIG. 10B is a diagram showing an example of time change of the discharge pressure determined to be inappropriate based on the evaluation based on the characteristic value Fv4. FIG. 11A is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv5. FIG. 11B is a diagram showing an example of time change of the discharge pressure determined to be inappropriate based on the evaluation of the characteristic value Fv5. FIG. 12 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv6. FIG. 13 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv7. FIG. 14 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv8. FIG. 15 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv9. FIG. 16 is a diagram for explaining evaluation items for evaluating the time change of the discharge pressure based on the characteristic amount Fv10. FIG. 17 is a diagram for explaining each period used in a modification of the evaluation item of discharge pressure. FIG. 18 is a diagram for explaining a modification of the evaluation item for evaluating the time change of the discharge pressure based on the feature amount Fv1_1.

Lr_F: falling regression line

Lr_R: rising regression line

Lr_e: Approximate straight line at the end

Lr_m: stable straight line

Lr_s: approximate straight line at the beginning

Pi: initial pressure

Pm: stable pressure

ta, te: time

t11, t12, t13, t14: time

WF1: Approximate waveform (first approximate waveform)

Claims (21)

A discharge pressure evaluation method comprising the step of measuring the discharge pressure during an evaluation target period including at least a main period in which processing is discharged from a nozzle by applying the discharge pressure to a processing liquid. The liquid discharge device starts to discharge the treatment liquid from the nozzle, passes through the period when the discharge pressure rises to a predetermined pressure, and ends when the discharge pressure starts to decrease from the predetermined pressure; the discharge pressure of the entire evaluation target period is selected. The step of using the characteristic quantity of the temporal change as an overall characteristic quantity; and the step of evaluating the temporal variation of the discharge pressure based on the overall characteristic quantity. The discharge pressure evaluation method according to claim 1, wherein the evaluation target period is the main period, and the characteristic quantity of the temporal change of the discharge pressure in the entire main period is extracted as the main characteristic quantity as the overall characteristic quantity. The discharge pressure evaluation method of claim 2, wherein the main characteristic quantity represents a main approximate waveform that approximates the time change of the discharge pressure in the entire main period, and the time change of the discharge pressure in the entire main period. Difference. The discharge pressure evaluation method of claim 3, wherein the main approximate waveform has an ascending approximate straight line, which increases linearly with time from the discharge start pressure to a stable pressure greater than the discharge start pressure. is large, its straight line approximates the starting point since The time change of the above-mentioned discharge pressure that increases with the passage of time after the above-mentioned nozzle discharges the treatment liquid; the initial approximate straight line is set between the time point when the above-mentioned nozzle starts to discharge the treatment liquid and the above-mentioned rising approximate straight line, indicating the above-mentioned The discharge start pressure; and a stable straight line, which is provided between the time when the above-mentioned rising approximate straight line reaches the above-mentioned stable pressure and the end of the above-mentioned main period, indicating the above-mentioned stable pressure. The discharge pressure evaluation method of Claim 1, wherein the evaluation target period is a first period from when the nozzle discharges the processing liquid to when the processing liquid discharge from the nozzle ends, and the discharge pressure is selected from the entire first period. The first characteristic quantity, which is a characteristic quantity of the time change of the pressure, serves as the above-mentioned overall characteristic quantity. The discharge pressure evaluation method of claim 5, wherein the first characteristic quantity represents a first approximate waveform that approximates the temporal change of the discharge pressure in the entire first period, and the discharge pressure in the entire first period. The difference in time changes. The discharge pressure evaluation method of claim 6, wherein the first approximate waveform has a rising approximate straight line that is a straight line approximation to the discharge pressure that increases with the passage of time after the process liquid starts to be discharged from the nozzle. Time changes, whereby the discharge start pressure increases linearly with the passage of time until the stable pressure is greater than the discharge start pressure; The starting approximate straight line is set between the start time point of discharging the treatment liquid from the nozzle and the rising approximate straight line, indicating the discharge starting pressure; the falling approximate straight line is a straight line approximating the end of discharging the treatment liquid from the nozzle. The time change of the above-mentioned discharge pressure that decreases with the passage of time, thereby linearly decreasing with the passage of time from the above-mentioned stable pressure to the discharge end pressure that is smaller than the above-mentioned stable pressure; at the end, it is approximately a straight line, which is disposed between the above-mentioned falling approximate straight line and the end time point of discharging the treatment liquid from the above-mentioned nozzle, and represents the above-mentioned discharge end pressure; and a stable straight line, which connects the above-mentioned rising approximate straight line and the above-mentioned falling approximate straight line, represents The above stable pressure. The discharge pressure evaluation method of claim 1 further includes the step of extracting a characteristic amount of the temporal change of the discharge pressure in a second period shorter than the evaluation target period among the evaluation target periods, as The step of the second characteristic quantity: evaluating the time change of the discharge pressure based on the above-mentioned overall characteristic quantity and the above-mentioned second characteristic quantity. The discharge pressure evaluation method of claim 8, wherein a predetermined initial rising period after the process liquid is discharged from the nozzle is set as the second period, and the discharge pressure increases with the passage of time during the entire initial rising period. increase, From the difference between the 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, a feature quantity representing the difference is extracted as the second feature quantity. The discharge pressure evaluation method according to claim 8, wherein the rising period from when the nozzle starts discharging the treatment liquid until the discharge pressure increases to the predetermined pressure is set as the second period. In the discharge pressure evaluation method of claim 10, the length of the rising period is extracted as the second characteristic quantity. The discharge pressure evaluation method of claim 10, wherein the number of times a first derivative of the time change of the discharge pressure crosses a predetermined threshold value during the rising period is selected as the second characteristic quantity. The discharge pressure evaluation method of Claim 10, wherein the number of times an absolute value of the second derivative of the time change of the discharge pressure crosses a predetermined threshold value during the rising period is selected as the second characteristic quantity. The discharge pressure evaluation method of Claim 10, wherein during the rising period, the time when the second derivative of the time change of the discharge pressure becomes larger than a predetermined positive threshold value, and the time when the time change of the discharge pressure The ratio of the time at which the quadratic differential becomes smaller than a predetermined negative threshold value having the same absolute value as the positive threshold value is extracted as the second feature quantity. The discharge pressure evaluation method according to any one of claims 8 to 14, wherein a predetermined rising end period until the discharge pressure increases to the predetermined pressure is set as the second period, The difference between the rise end approximate waveform that approximates the time change of the discharge pressure during the rise end period and the time change of the discharge pressure during the rise end period is extracted as the second feature. quantity, the above-mentioned approximate waveform at the end of rise has: an approximate straight line at the end of rise, which is a linear approximation to the time change of the above-mentioned discharge pressure that increases with the passage of time in a pressure range smaller than the above-mentioned predetermined pressure, and is obtained The approximate curve increases linearly with the passage of time until the average value of the time change of the discharge pressure in the stable period after the above-mentioned end-of-rise period is the stable pressure; and a straight line is extended from the above-mentioned end-of-rise period. The approximate straight line extending to the end time point of the above-mentioned rising terminal period represents the above-mentioned stable pressure. The method for evaluating discharge pressure according to any one of claims 8 to 14, wherein: from the time point when the above-mentioned discharge pressure reaches the maximum value to the time point when the second derivative of the time change of the above-mentioned discharge pressure crosses zero twice The initial vibration period until The difference between the maximum value of the discharge pressure is extracted and used as the second feature quantity. The discharge pressure evaluation method according to any one of claims 8 to 14, wherein a predetermined transition period from the time point when the discharge pressure exceeds the predetermined pressure is set as the second period, From the difference between the discharge pressure during the transition period and the average value of the discharge pressure during a predetermined stable period after the transition period, a characteristic quantity representing the difference is extracted as the second characteristic quantity. The discharge pressure evaluation method according to any one of claims 8 to 14, wherein the time from when the discharge pressure exceeds the predetermined pressure to the time when the discharge pressure starts to decrease toward the end of discharge of the treatment liquid from the nozzle The constant pressure period up to the point is set as the second period, and a characteristic quantity representing the difference between the maximum value and the minimum value of the discharge pressure in the constant pressure period is extracted as the second characteristic quantity. A discharge pressure evaluation program that causes a computer to execute the step of measuring the discharge pressure in an evaluation target period including at least a main period in which the process liquid is discharged from a nozzle by applying the discharge pressure to the process liquid. The discharge device of the processing liquid starts to discharge the processing liquid from the nozzle, passes through the period when the discharge pressure rises to a predetermined pressure, and ends when the discharge pressure starts to decrease from the predetermined pressure; the discharge pressure is selected from the entire evaluation target period. The step of using the characteristic quantity of the temporal change as an overall characteristic quantity; and the step of evaluating the temporal variation of the discharge pressure based on the overall characteristic quantity. A recording medium including the discharge pressure evaluation program described in claim 19, the discharge pressure evaluation program being recorded in a computer-readable manner. A substrate processing apparatus is provided with: a nozzle; and a pressure applying part that applies a discharge pressure to a processing liquid to cause the nozzle to discharge the processing liquid; a measurement unit that measures the discharge pressure; and a control unit that obtains the discharge pressure measured by the measurement unit during an evaluation target period including at least a main period from the start of the nozzle discharge process The period during which the discharge pressure rises to a predetermined pressure after the liquid rises until the discharge pressure starts to decrease from the predetermined pressure; the control unit extracts the characteristic amount of the temporal change of the discharge pressure in the entire evaluation target period as The overall characteristic quantity is used to evaluate the time change of the discharge pressure based on the overall characteristic quantity.