JP2014179450A - Ejection inspection device and substrate processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine whether or not the ejection action at each of a plurality of ejection openings is favorable with a high degree of accuracy.SOLUTION: At an ejection inspection part 5 of a substrate processing device 1, a light emission part 51 emits the light along a predetermined light present surface, and process liquid ejected from a plurality of ejection openings of an ejection head 31 is irradiated with the light. An imaging part 52 images the process liquid through which the planar light 510 from the light emission part 51 passes, and acquires an inspection image including a plurality of bright points. At the ejection inspection part 5, a plurality of normal ejection determination frame corresponding to a plurality of ejection openings on the inspection image are set by a determination frame setting part. Subsequently, a size of the normal ejection determination frame is adjusted based on a distance from the imaging part 52. The determination part acquires a presence/absence information of the bright point in each of normal ejection determination frame, and determines whether or not the ejection action at ejection openings corresponding to each normal ejection determination frame is favorable on the basis of the presence/absence information. Thereby it is possible to determine whether or not the ejection action at each of a plurality of ejection openings is favorable with a high degree of accuracy.

Description

  The present invention relates to a discharge inspection apparatus for inspecting a liquid discharge operation from a plurality of discharge ports, and a substrate processing apparatus including the discharge inspection apparatus.

  Conventionally, in a manufacturing process of a semiconductor substrate (hereinafter simply referred to as “substrate”), various processes are performed on a substrate having an insulating film such as an oxide film using a substrate processing apparatus. For example, a cleaning process is performed to remove particles and the like attached on the surface of the substrate by supplying a cleaning liquid to the surface of the substrate.

  Patent Document 1 discloses a substrate processing apparatus that discharges a photoresist liquid onto a substrate from one processing liquid supply nozzle disposed above the substrate. In this apparatus, the CCD camera is directed between the processing liquid supply nozzle and the substrate, and the liquid column of the processing liquid discharged from the processing liquid supply nozzle is imaged. Then, the liquid column width of the imaged processing liquid (that is, the discharge width from the processing liquid supply nozzle) is compared with a predetermined reference width, and when it is smaller than the reference width, it is detected as an abnormal discharge.

  Patent Document 2 discloses a substrate processing apparatus that applies developer to a substrate held in a stationary state from a slit-like discharge port of a developer discharge nozzle. In the apparatus, illumination for irradiating light on the substrate and a light detection unit for detecting light reflected by the processing liquid on the substrate are provided. An image of the entire surface of the substrate is acquired by the CCD camera of the light detection unit, and a developing solution supply failure region where the developing solution is not accumulated on the substrate is detected based on a difference in brightness value from other regions. .

  Patent Document 3 discloses a liquid processing apparatus that supplies a coating liquid from a coating liquid nozzle onto a substrate. In this apparatus, the coating liquid nozzle is transported between the upper part of the substrate and the nozzle bus that is the standby position, and the tip of the coating liquid nozzle being transported is imaged. Based on the imaging result, the occurrence of dripping or dripping from the tip of the coating liquid nozzle is detected.

  Patent Document 4 discloses a liquid processing apparatus that supplies a processing liquid onto a substrate from a processing liquid nozzle. In this apparatus, 11 nozzles arranged in a line in a straight line are held by the nozzle head portion. In addition, a line-shaped laser beam is irradiated to a region from the tip portion of these nozzles to the substrate surface, and a liquid column of the resist solution discharged from each nozzle is imaged by a camera directed to the region. Then, by comparing the imaging result with the reference information obtained by imaging the state in which the resist solution is normally ejected from the nozzle, it is determined whether the resist solution is ejected from the nozzle and whether the ejection state has changed. Is done.

  On the other hand, Patent Document 5 discloses a substrate processing apparatus that discharges fine droplets of a processing liquid toward a substrate from a plurality of discharge ports. In the apparatus, a plurality of discharge port arrays in which a plurality of discharge ports are arranged in one row are provided.

JP 11-329936 A JP 2003-272986 A JP 2008-135679 A JP 2012-98812 A JP 2012-209513 A

  By the way, in an apparatus such as Patent Document 5, even if it is determined whether or not the processing liquid is being discharged from a plurality of discharge ports, a plurality of discharge port arrays each having a large number of discharge ports are arranged in an array of discharge ports. Since the liquid droplets are arranged in a direction crossing the direction, the fine liquid droplets from the respective discharge ports overlap with each other, and it is not easy to determine which fine liquid droplet corresponds to which discharge port.

  Further, as one of abnormal discharges of micro droplets, there is an oblique discharge that is discharged out of a predetermined discharge direction. As a method for detecting such oblique ejection, it is conceivable to compare the interval between the minute droplets with a normal value. However, since the interval between the minute droplets appears large at the discharge port close to the observation viewpoint and appears small at the discharge port far from the observation viewpoint, it is not easy to determine whether the discharge is normal discharge or oblique discharge. In addition, the size of each minute droplet also changes depending on the distance from the observation viewpoint.

  The present invention has been made in view of the above problems, and an object of the present invention is to accurately determine the quality of a discharge operation at each of a plurality of discharge ports.

  The invention according to claim 1 is a discharge inspection device for inspecting the discharge operation of liquid from a plurality of discharge ports, and emits light along a predetermined light existence surface, whereby the plurality of discharge ports A plurality of projectiles that are liquids ejected from the light exiting unit that emits light to the plurality of projectiles when passing through the light-existing surface; and imaging the plurality of projectiles that pass through the light-existing surface An image capturing unit that acquires an inspection image including a plurality of bright spots appearing on the plurality of flying objects, and a determination for setting a plurality of normal ejection determination frames corresponding to the plurality of ejection ports on the inspection image. A frame setting unit, and a determination unit that acquires presence / absence information of a bright spot in each normal discharge determination frame, and determines whether the discharge operation at the discharge port corresponding to each normal discharge determination frame is good or not based on the presence / absence information The determination frame setting section includes A normal discharge determination frame of a predetermined size is centered on a bright spot reference position, which is a point where a discharge center line extending from each discharge port in the design discharge direction of the flying object intersects the light existence surface. The temporary setting unit temporarily set on the inspection image corresponding to the exit, and each normal ejection determination frame temporarily set by the temporary setting unit is a distance between the bright spot reference position and the imaging unit A frame size adjusting unit that adjusts based on the inspection distance.

  Invention of Claim 2 is the discharge inspection apparatus of Claim 1, Comprising: It is the discharge inspection apparatus of Claim 1, Comprising: The said frame size adjustment part is a magnitude | size of each said normal discharge determination frame. An adjustment is performed to reduce the inspection distance as the inspection distance increases.

  Invention of Claim 3 is the discharge inspection apparatus of Claim 1 or 2, Comprising: The said frame size adjustment part makes the magnitude | size of each said normal discharge determination frame the focusing distance of the said imaging part, and Adjustment is made to reduce as the difference from the inspection distance increases.

  A fourth aspect of the present invention is the ejection inspection apparatus according to any one of the first to third aspects, wherein the light in a direction parallel to an optical axis between the light emitting portion and the bright spot reference position. With the distance between the emitting part and the bright spot reference position as an irradiation distance, the frame size adjusting part is a light thinnest position where the thickness of the light emitted from the light emitting part is the smallest in the ejection direction. A light thickness adjusting unit is further provided that reduces each normal ejection determination frame in the ejection direction as the difference between the distance from the light emitting unit and the irradiation distance increases.

  A fifth aspect of the present invention is the ejection inspection apparatus according to any one of the first to fourth aspects, wherein the imaging direction of the imaging unit is inclined with respect to a plane perpendicular to the ejection direction.

  A sixth aspect of the present invention is the discharge inspection apparatus according to any one of the first to fifth aspects, wherein the light existence surface is inclined with respect to a plane perpendicular to the discharge direction.

  A seventh aspect of the present invention is the discharge inspection apparatus according to any one of the first to sixth aspects, wherein the plurality of discharge ports are arranged in a straight line, and the determination frame setting unit includes the inspection frame setting unit. The positions of the plurality of normal ejection determination frames are set based on the positions of the bright spots located at both ends of the plurality of bright spots included in the image.

  The invention according to claim 8 is the discharge inspection apparatus according to any one of claims 1 to 7, wherein the determination frame setting unit includes a plurality of oblique discharge determination frames around the plurality of normal discharge determination frames. And the determination unit determines whether or not an oblique discharge has occurred at the discharge port corresponding to each oblique discharge determination frame based on the presence or absence of a bright spot in each oblique discharge determination frame.

  The invention described in claim 9 is the discharge inspection apparatus according to claim 8, wherein the determination frame setting unit sets one outer discharge determination frame around the plurality of oblique discharge determination frames, The determination unit determines whether or not a larger oblique discharge has occurred based on the presence / absence information of a bright spot in the outer discharge determination frame.

  A tenth aspect of the present invention is the discharge inspection apparatus according to any one of the first to seventh aspects, wherein the determination frame setting unit has one oblique discharge determination frame around the plurality of normal discharge determination frames. And the determination unit determines whether or not oblique discharge has occurred based on the presence or absence of a bright spot in the oblique discharge determination frame.

  The invention according to claim 11 is the discharge inspection apparatus according to claim 10, wherein the determination frame setting unit sets one outer discharge determination frame around the oblique discharge determination frame, and the determination unit However, the presence / absence of a larger oblique discharge is determined based on the presence / absence information of the bright spot in the outer discharge determination frame.

  The invention according to claim 12 is the ejection inspection apparatus according to any one of claims 1 to 11, wherein the determination unit obtains the center of gravity of each of the plurality of bright spots on the inspection image, and The presence / absence of the center of gravity of the bright spot in each normal discharge determination frame is acquired as the presence / absence information of the bright spot in each normal discharge determination frame.

  The invention according to claim 13 is a substrate processing apparatus, comprising: a substrate holding unit that holds a substrate; a discharge head that discharges liquid from a plurality of discharge ports toward the substrate and performs a predetermined process on the substrate; The discharge inspection apparatus according to claim 1, wherein the discharge operation of the liquid from the plurality of discharge ports of the discharge head is inspected.

  In the present invention, it is possible to accurately determine the quality of the ejection operation at each of the plurality of ejection ports.

It is a front view of the substrate processing apparatus concerning one embodiment. It is a top view of a substrate processing apparatus. It is a side view of a discharge head and a standby pod. It is a bottom view which shows the lower surface of a discharge head. It is a block diagram which shows the function of a control unit. It is a perspective view which shows an ejection head, a light emission part, and an imaging part. It is a figure which shows a test | inspection image. It is a figure which shows a test | inspection image. It is a conceptual diagram which shows a part of discharge head, planar light, and a protective liquid film. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a part of test | inspection image. It is a figure which shows a test | inspection image. It is a figure which shows a test | inspection image. It is a figure which shows a test | inspection image. It is a figure which shows a test | inspection image. It is a figure which shows a test | inspection image.

  FIG. 1 is a front view of a substrate processing apparatus 1 according to an embodiment of the present invention. FIG. A is a plan view of the substrate processing apparatus 1. FIG. In A, the orientation of the substrate processing apparatus 1 is changed from FIG. The substrate processing apparatus 1 is a single-wafer type apparatus that processes semiconductor substrates 9 (hereinafter simply referred to as “substrates 9”) one by one. In the substrate processing apparatus 1, a liquid is discharged to the substrate 9 to perform a predetermined process. In the present embodiment, a cleaning process for removing particles and the like from the substrate 9 is performed by discharging droplets of the cleaning liquid onto the substrate 9. In the substrate processing apparatus 1, for example, droplets having a diameter of about 20 μm are ejected toward the substrate 9 in a spray form.

  1 and 2. As shown in A, the substrate processing apparatus 1 includes a substrate holding unit 21, a cup unit 22, a substrate rotating mechanism 23, a processing liquid supply unit 3, a supply unit moving mechanism 35, a protective liquid supply unit 36, A standby pod 4, a discharge inspection unit 5, a chamber 6, and a control unit are provided. The chamber 6 includes the substrate holding unit 21, the cup unit 22, the substrate rotating mechanism 23, the processing liquid supply unit 3, the supply unit moving mechanism 35, the protective liquid supply unit 36, the standby pod 4, and the discharge inspection unit 5. 60. The chamber 6 is a light shielding chamber that blocks light from entering the internal space 60 from the outside. 1 and 2. In A, the chamber 6 is indicated by a broken line, and the inside of the chamber 6 is illustrated.

  The substrate holding unit 21 holds the substrate 9 in a state where one main surface 91 (hereinafter referred to as “upper surface 91”) of the substrate 9 is directed upward in the chamber 6. A fine pattern such as a circuit pattern is formed on the upper surface 91 of the substrate 9. The cup portion 22 is a substantially cylindrical member surrounding the substrate 9 and the substrate holding portion 21. The substrate rotation mechanism 23 is disposed below the substrate holding unit 21. The substrate rotation mechanism 23 rotates the substrate 9 together with the substrate holder 21 in a horizontal plane around a rotation axis that passes through the center of the substrate 9 and is perpendicular to the upper surface 91 of the substrate 9.

  The processing liquid supply unit 3 includes a discharge head 31 that discharges the processing liquid downward, and a processing liquid pipe 32 that supplies the processing liquid to the discharge head 31. The discharge head 31 is disposed above the substrate holding part 21 inside the cup part 22. In other words, the lower surface of the ejection head 31 is located between the upper opening 220 of the cup portion 22 and the upper surface 91 of the substrate 9. The discharge head 31 is a device that continuously discharges minute droplets separated from each other from a plurality of discharge ports described later. The processing liquid is discharged toward the upper surface 91 of the substrate 9 by the discharge head 31. As the treatment liquid, a liquid such as pure water (preferably deionized water (DIW)), carbonated water, a mixed solution of ammonia water and hydrogen peroxide water is used. The design discharge direction of the processing liquid from the discharge head 31 is approximately parallel to the vertical direction (that is, the direction of gravity).

  FIG. 3 is a bottom view showing the lower surface 311 of the ejection head 31. The lower surface 311 of the discharge head 31 is provided with a plurality of discharge ports including four discharge port arrays 313a to 313d. Each of the discharge port arrays 313a to 313d has a plurality of discharge ports 314a to 314d arranged linearly in the left-right direction in FIG. 3 at a predetermined arrangement pitch. The diameter of each discharge port 314a-314d is about 5 micrometers-10 micrometers. In FIG. 3, each of the discharge ports 314a to 314d is drawn larger than the actual size, and the number of the discharge ports 314a to 314d is drawn smaller than the actual size. In FIG. 3, a discharge port arrangement region 316 where a plurality of discharge ports 314 a to 314 d are provided on the lower surface 311 of the discharge head 31 is surrounded by a two-dot chain line. The discharge port arrangement region 316 is substantially rectangular. In the ejection head 31, minute droplets of the processing liquid are ejected from each of the plurality of ejection ports 314a to 314d.

  In the following description, the horizontal direction in FIG. Further, the discharge port arrays 313a to 313d arranged from the upper side to the lower side in FIG. 3 are respectively referred to as “first discharge port array 313a”, “second discharge port array 313b”, and “third discharge port array 313c”. And “fourth outlet row 313d”. Furthermore, the plurality of discharge ports 314a of the first discharge port row 313a are referred to as “first discharge ports 314a”, and the plurality of discharge ports 314b of the second discharge port row 313b are referred to as “second discharge ports 314b”. The plurality of discharge ports 314c of the third discharge port row 313c are referred to as “third discharge ports 314c”, and the plurality of discharge ports 314d of the fourth discharge port row 313d are referred to as “fourth discharge ports 314d”.

  The first discharge port row 313a, the second discharge port row 313b, the third discharge port row 313c, and the fourth discharge port row 313d are linear shapes extending in the above-described arrangement direction, and are arranged in parallel to each other. In the direction perpendicular to the arrangement direction (that is, the vertical direction in FIG. 3), the distance between the first discharge port array 313a and the second discharge port array 313b is the third discharge port array 313c and the fourth discharge port array. It is equal to the distance between 313d and smaller than the distance between the 2nd discharge port row | line | column 313b and the 3rd discharge port row | line | column 313c. The second discharge port array 313b is arranged so as to be shifted from the first discharge port array 313a by a predetermined shift distance on the right side in FIG. 3, which is one side in the arrangement direction. The fourth discharge port array 313d is arranged to be shifted from the third discharge port array 313c by the shift distance on the right side in FIG. The shift distance is a distance smaller than the above-described arrangement pitch, for example, a distance that is half of the arrangement pitch.

  In the ejection head 31, when viewed from a direction perpendicular to the arrangement direction and parallel to the lower surface 311 of the ejection head 31, the plurality of first ejection ports 314a and the plurality of second ejection ports 314b are alternately arranged in the arrangement direction. The plurality of third discharge ports 314c and the plurality of fourth discharge ports 314d are alternately arranged in the arrangement direction. In addition, the plurality of first discharge ports 314a and the plurality of third discharge ports 314c overlap each other, and the plurality of second discharge ports 314b and the plurality of fourth discharge ports 314d overlap each other.

  1 and 2. As shown to A, the supply part moving mechanism 35 is provided with the arm 351, the rotating shaft 352, the head rotating mechanism 353, and the head raising / lowering mechanism 354. The arm 351 extends in the horizontal direction from the rotation shaft 352. A discharge head 31 is attached to the tip of the arm 351. The head rotation mechanism 353 rotates the ejection head 31 in the horizontal direction around the rotation shaft 352 together with the arm 351. The head lifting mechanism 354 moves the ejection head 31 in the vertical direction together with the arm 351. The head rotation mechanism 353 includes, for example, an electric motor. The head lifting mechanism 354 includes, for example, a ball screw mechanism and an electric motor.

  The protective liquid supply unit 36 is directly or indirectly fixed to the discharge head 31 and discharges the protective liquid obliquely downward. As the protective liquid, liquids such as pure water (preferably deionized water), carbonated water, a mixed solution of ammonia water and hydrogen peroxide water are used as in the case of the above-described treatment liquid. The protective liquid may be the same type of liquid as the treatment liquid or may be a different type of liquid. In the substrate processing apparatus 1, the protective liquid discharged in the form of a liquid column from the protective liquid supply unit 36 toward the upper surface 91 of the substrate 9 spreads on the substrate 9 below the discharge head 31, thereby directly below the discharge head 31. A protective liquid film (hereinafter referred to as “protective liquid film”) having a predetermined thickness is formed. The protective liquid supply unit 36 moves together with the ejection head 31 by the head rotation mechanism 353 and the head lifting mechanism 354.

  FIG. 4 is a block diagram showing functions of the control unit 7. In FIG. 4, the configuration other than the control unit 7 is also drawn. The control unit 7 includes a process control unit 71, an inspection control unit 72, and an inspection calculation unit 73. The processing of the substrate 9 is performed by controlling the substrate rotation mechanism 23, the processing liquid supply unit 3, the supply unit moving mechanism 35, the protective liquid supply unit 36, and the like by the processing control unit 71. The inspection control unit 72 controls the processing liquid supply unit 3, the supply unit moving mechanism 35, the discharge inspection unit 5, and the like, thereby inspecting the discharge operation of the processing liquid from the plurality of discharge ports 314a to 314d of the discharge head 31. Is done.

  The inspection calculation unit 73 is a part of the ejection inspection unit 5, and includes a determination frame setting unit 74, a determination unit 75, and a bright spot correction unit 76. The determination frame setting unit 74 includes a temporary setting unit 77 and a frame size adjustment unit 78. The frame size adjustment unit 78 includes an apparent frame size adjustment unit 78a, an out-of-focus frame size adjustment unit 78b, and a light thickness adjustment unit 78c. The bright spot correcting unit 76 includes an apparent bright spot size correcting unit 76a, an out-of-focus bright spot size correcting unit 76b, and a light thickness correcting unit 76c. The determination frame setting unit 74, the determination unit 75, and the bright spot correction unit 76 are used for the above-described ejection operation inspection.

  In the frame size adjustment unit 78, the apparent frame size adjustment unit 78a, the out-of-focus frame size adjustment unit 78b, and the light thickness adjustment unit 78c are appropriately combined according to first to fourth adjustment methods described later. Used. Similarly, in the bright spot correction unit 76, the apparent bright spot size correction unit 76a, the out-of-focus bright spot size correction unit 76b, and the light thickness correction unit 76c are used in first to fourth adjustment methods described later. It is used in combination accordingly.

  1 and 2. When the substrate 9 is processed in the substrate processing apparatus 1 shown in A, the substrate 9 is first carried into the chamber 6 and held by the substrate holder 21. When the substrate 9 is carried in, the ejection head 31 moves as shown in FIG. As indicated by a two-dot chain line in A, the apparatus waits at a standby position on the standby pod 4 provided outside the cup portion 22. FIG. B is a side view showing the ejection head 31 located at the standby position in an enlarged manner together with the standby pod 4. The standby pod 4 is a substantially rectangular parallelepiped container, and has an opening at the top. At the standby position, a part of the ejection head 31 is inserted into the standby pod 4 through the opening. Note that FIG. In B, the protective liquid supply part 36 is not shown. In addition, a discharge head 31 located at an inspection position described later is indicated by a two-dot chain line. When the substrate 9 is held by the substrate holding unit 21, the substrate rotation mechanism 23 is driven by the process control unit 71 and rotation of the substrate 9 is started.

  Subsequently, the head rotation mechanism 353 and the head elevating mechanism 354 are driven by the processing control unit 71, and the ejection head 31 and the protective liquid supply unit 36 are lifted from the standby position, moved downward above the cup unit 22, and then lowered. . Accordingly, the ejection head 31 and the protective liquid supply unit 36 move to the inside of the cup unit 22 and above the substrate holding unit 21 through the upper opening 220 of the cup unit 22. Next, supply of the protective liquid from the protective liquid supply unit 36 onto the substrate 9 is started, and a protective liquid film covering a part of the upper surface 91 of the substrate 9 is formed. In addition, the processing liquid is started to be ejected (that is, the ejection of minute droplets) from the plurality of ejection ports 314a to 314d of the ejection head 31 toward the upper surface 91 of the substrate 9 on which the protective liquid film is formed. The protective liquid film covers a plurality of design landing points (that is, landing points of the micro droplets) on the substrate 9 of the processing liquid from the plurality of discharge ports 314a to 314d.

  A number of micro droplets ejected from the ejection head 31 toward the protective liquid film collide with the protective liquid film on the upper surface 91 of the substrate 9 and indirectly collide with the upper surface 91 of the substrate 9 through the protective liquid film. To do. Then, foreign matters such as particles adhering to the upper surface 91 of the substrate 9 are removed from the substrate 9 by the impact caused by the collision of the minute droplets of the processing liquid. In other words, the cleaning process of the upper surface 91 of the substrate 9 is performed by the kinetic energy indirectly applied to the substrate 9 through the protective liquid film by the fine droplets of the processing liquid.

  In this way, the microdroplets of the processing liquid collide with the substrate 9 through the protective liquid film, so that the microdroplets are formed on the upper surface 91 of the substrate 9 as compared with the case where the microdroplets directly collide with the substrate. The substrate 9 can be cleaned while preventing or suppressing damage to the pattern or the like. In addition, since the portion of the substrate 9 on which the cleaning process is performed is covered with the protective liquid, it is possible to prevent or suppress particles and the like removed from the substrate 9 from reattaching to the upper surface 91 of the substrate 9. it can.

  In the substrate processing apparatus 1, the ejection head 31 and the protection liquid supply unit 36 are rotated by the head rotation mechanism 353 in parallel with the discharge of the protection liquid and the processing liquid. The ejection head 31 and the protective liquid supply unit 36 repeat horizontal reciprocation between the upper part of the rotating substrate 9 and the upper part of the outer edge of the substrate 9. Thereby, the cleaning process is performed on the entire upper surface 91 of the substrate 9. The protective liquid and the processing liquid supplied to the upper surface 91 of the substrate 9 are scattered from the edge of the substrate 9 to the outside by the rotation of the substrate 9. The protective liquid and the processing liquid splashed from the substrate 9 are received by the cup portion 22 and discarded or collected.

  When the predetermined process (that is, the cleaning process of the substrate 9) with the processing liquid from the discharge head 31 is completed, the discharge of the protective liquid and the processing liquid is stopped. The discharge head 31 and the protective liquid supply unit 36 are raised above the upper opening 220 of the cup unit 22 by the head lifting mechanism 354, and the inspection position above the standby pod 4 by the head rotation mechanism 353 (see FIG. 2.B). Move to. The inspection position is a position above the standby position described above. At the inspection position of the ejection head 31, the ejection inspection unit 5 inspects the processing liquid ejection operation from the plurality of ejection ports 314 a to 314 d of the ejection head 31 periodically or as necessary.

  FIG. 5 is a perspective view showing the ejection head 31 at the inspection position and the ejection inspection unit 5 arranged around the ejection head 31. The discharge inspection unit 5 includes a light emitting unit 51 and an imaging unit 52. The light emitting unit 51 and the imaging unit 52 are disposed obliquely below the ejection head 31, avoiding directly below the ejection head 31. The light emission part 51 and the imaging part 52 are controlled by the inspection control part 72 of the control unit 7, as shown in FIG.

  The light emitting unit 51 illustrated in FIG. 5 includes a light source and an optical system that converts light from the light source into linear light extending in a substantially horizontal direction. As the light source, for example, a laser diode or an LED (light emitting diode) element is used. The light emitting unit 51 emits light toward the lower side of the ejection head 31 along a light existence surface that is a predetermined virtual surface. In FIG. 5, the optical axis J <b> 1 of the light emitting part 51 is drawn with a one-dot chain line, and the outline of the planar light emitted from the light emitting part 51 is indicated with a two-dot chain line denoted by reference numeral 510.

  The planar light 510 from the light emitting portion 51 passes directly under the ejection head 31 in the vicinity of the lower surface 311 of the ejection head 31. In the substrate processing apparatus 1, a predetermined drive signal is sent from the inspection control unit 72 to the processing liquid supply unit 3 and is directed from the plurality of discharge ports 314 a to 314 d (see FIG. 3) of the discharge head 31 toward the inside of the standby pod 4. The processing liquid is discharged. Then, when a plurality of flying bodies that are processing liquids discharged from the plurality of discharge ports 314 a to 314 d of the discharge head 31 pass through the above-described light existence surface (that is, pass through the planar light 510), Light is emitted from the emitting unit 51 to the plurality of flying objects. The planar light 510 is approximately perpendicular to the designed ejection direction of the processing liquid from the ejection head 31 (that is, a predetermined ejection direction determined in advance for a plurality of flying objects). Strictly speaking, the planar light 510 (that is, the light existing surface) is inclined by a slight angle (for example, 5 ° to 10 °) with respect to a plane perpendicular to the predetermined ejection direction of the plurality of flying objects. Preferably it is.

  The imaging unit 52 is disposed below the light existence surface with the imaging axis J2 facing the planar light 510 positioned below the ejection head 31. The imaging direction (that is, the direction in which the imaging axis J2 faces) in the imaging unit 52 is inclined with respect to a plane perpendicular to the predetermined ejection direction of the plurality of flying objects. As the imaging unit 52, for example, a charge-coupled device (CCD) camera is used. The imaging unit 52 acquires an inspection image including a plurality of bright spots appearing on the plurality of flying bodies by imaging the processing liquid (that is, a plurality of flying bodies) that passes through the planar light 510. In the ejection inspection unit 5, one frame of a still image is extracted as an inspection image from the imaging result obtained by the imaging unit 52. The imaging unit 52 is arranged at a position where the first discharge port array 313a is visible on the front side among the four discharge port arrays 313a to 313d in FIG.

  FIG. 6 is a diagram showing the inspection image 8. In the inspection image 8, a plurality of bright spots 81 respectively corresponding to the plurality of ejection ports 314a to 314d of the ejection head 31 are arranged in a direction corresponding to the arrangement direction of the ejection ports 314a to 314d. In the ejection inspection unit 5, since the planar light 510 has a slight thickness, each bright spot 81 has a substantially elliptical shape that is long in the direction corresponding to the vertical direction in the inspection image 8. As will be described later, some of the plurality of bright spots 81 are located outside the in-focus range of the imaging unit 52 and are blurred on the inspection image 8 (so-called out of focus). Compared with the other bright spots 81, it spreads greatly. In FIG. 6, the focusing range is shown surrounded by a two-dot chain line denoted by reference numeral 80. Further, with respect to the bright spot 81 located outside the focusing range 80, the size of the bright spot when it is assumed that the bright spot 81 is located inside the focusing range 80 is indicated by a thin line. The same applies to FIGS. 7, 10, 12 to 16.

  The output from the imaging unit 52 is sent to the inspection calculation unit 73 (see FIG. 4) of the control unit 7. In the inspection calculation unit 73, a binarization process is performed on the inspection image 8, and a plurality of bright spots 81 are extracted and background noise and the like are removed.

  Subsequently, as shown in FIG. 7, a plurality of normal ejection determination frames 85 respectively corresponding to the plurality of discharge ports 314 a to 314 d on the inspection image 8 are displayed on the inspection image 8 by the determination frame setting unit 74 (see FIG. 4). Set to The number of normal ejection determination frames 85 is equal to the number of ejection ports 314a to 314d. Each normal discharge determination frame 85 has a substantially rectangular shape with a predetermined size, and the sizes of the plurality of normal discharge determination frames 85 on the inspection image 8 are equal to each other. In the present embodiment, each normal ejection determination frame 85 is substantially square, and its four sides are parallel to the vertical direction or the horizontal direction of the inspection image 8. Each normal discharge determination frame 85 passes when the processing liquid is discharged from a corresponding discharge port in a predetermined discharge direction or in a direction slightly shifted from the discharge direction by a shift amount within an allowable range. An area on the planar light 510 is shown.

  The plurality of normal ejection determination frames 85 are arranged in a direction corresponding to the above-described arrangement direction on the inspection image 8. In the following description, the normal discharge determination frame 85 corresponding to the first discharge port row 313a, the second discharge port row 313b, the third discharge port row 313c, and the fourth discharge port row 313d will be referred to as “first normal discharge”. These are referred to as “determination frame column 86a”, “second normal ejection determination frame column 86b”, “third normal ejection determination frame column 86c”, and “fourth normal ejection determination frame column 86d”.

  The position of each normal discharge determination frame 85 on the inspection image 8 is determined based on the bright spot reference position of the processing liquid from the discharge port corresponding to each normal discharge determination frame 85. The bright spot reference position is a point at which the discharge center line extending from each discharge port in the design discharge direction of the processing liquid intersects with the planar light 510 (that is, the above-described light existence surface). Each normal ejection determination frame 85 is set around the bright spot reference position on the inspection image 8.

  The bright spot reference position on the inspection image 8 can be obtained by various methods. For example, the design position and orientation of the ejection head 31 at the inspection position, the positions of the ejection ports 314a to 314d in the ejection head 31, the design treatment liquid ejection direction, the position of the planar light 510, and the position of the imaging unit 52 Based on the above, the coordinates of each bright spot reference position in the three-dimensional coordinate system set in the substrate processing apparatus 1 are obtained. In other words, the coordinates of a plurality of bright spot reference positions are obtained based on the relative positions of the ejection head 31, the light emitting unit 51, and the imaging unit 52.

  Subsequently, the coordinates of the plurality of bright spot reference positions in the three-dimensional coordinate system with the imaging unit 52 as the origin are obtained by performing view conversion on the coordinates of the plurality of bright spot reference positions using the view conversion matrix. Next, the coordinates of the plurality of bright spot reference positions in the two-dimensional coordinate system on the inspection image 8 are acquired by performing perspective projection conversion on the coordinates of the plurality of bright spot reference positions subjected to view conversion. In the substrate processing apparatus 1, since the non-telecentric optical system is used for the imaging unit 52, perspective projection conversion is performed as described above, but when the telecentric optical system is used for the imaging unit 52, By performing orthogonal projection (also referred to as parallel projection or parallel projection) on the converted coordinates of the plurality of bright spot reference positions, the coordinates of the plurality of bright spot reference positions on the inspection image 8 are acquired.

  As shown in FIG. 7, the plurality of normal ejection determination frames 85 are arranged on the inspection image 8 without overlapping each other. When the normal ejection determination frames 85 overlap on the inspection image 8, the position and orientation of the imaging unit 52 and the planar light 510 from the light emitting unit 51 until the plurality of normal ejection determination frames 85 do not overlap each other. The position, orientation, etc. are changed, and the setting of the normal ejection determination frame 85 is repeated.

  When the setting of the normal discharge determination frame 85 is completed, the determination frame setting unit 74 sets a plurality of oblique discharge determination frames 87 around the plurality of normal discharge determination frames 85, respectively. The oblique discharge determination frame 87 is a determination frame having a substantially rectangular outline larger than the normal discharge determination frame 85. One normal discharge determination frame 85 is positioned inside each oblique discharge determination frame 87. The positions of the substantially square oblique discharge determination frames 87 are set based on the positions of the corresponding normal discharge determination frames 85. Specifically, each oblique discharge determination frame 87 is arranged so as to surround the normal discharge determination frame 85 so that the corresponding normal discharge determination frame 85 is located at the approximate center. The number of normal ejection determination frames 85 is equal to the number of oblique ejection determination frames 87. Each oblique ejection determination frame 87 indicates an area on the planar light 510 through which the processing liquid ejected in a direction deviated to some extent from a predetermined ejection direction passes.

  When the setting of the oblique discharge determination frame 87 is completed, the determination frame setting unit 74 causes a single protective liquid film discharge determination frame 88 corresponding to the protective liquid film on the substrate 9 to have a plurality of oblique discharge determinations on the inspection image 8. It is set around the frame 87. In the protective liquid film discharge determination frame 88, the processing liquid from a plurality of discharge ports (hereinafter referred to as “peripheral discharge ports”) disposed on the outer peripheral portion of the discharge port arrangement region 316 (see FIG. 3) is transferred to the substrate 9. An area on the planar light 510 that passes when the liquid is deposited on the upper protective liquid film is shown. The setting of the protective liquid film discharge determination frame 88 is positioned between the plurality of outer peripheral discharge ports, the position of the outer peripheral portion of the protective liquid film on the substrate 9, and between the plurality of outer peripheral discharge ports and the protective liquid film. This is performed based on the position of the light existing surface.

  Specifically, as shown in FIG. 8, the peripheral discharge on the outer peripheral portion of the protective liquid film 93 on the substrate 9 (more specifically, the outer peripheral edge of the protective liquid film 93) from one peripheral discharge port 314e. An imaginary line 94 is drawn toward the point closest to the exit 314e, and an intersection point 95 between the imaginary line 94 and the light existence surface (that is, the planar light 510) is obtained. Then, for each of the plurality of outer peripheral discharge ports 314e, a corresponding intersection point 95 is obtained on the planar light 510, and these intersection points 95 are projected on the inspection image 8 and connected in order, whereby the protective liquid film shown in FIG. An inner discharge determination frame 88 is set.

  When the setting of the in-protection liquid film discharge determination frame 88 is completed, the determination frame setting unit 74 sets one maximum discharge determination frame 89 surrounding the in-protection liquid film discharge determination frame 88 on the inspection image 8. The maximum discharge determination frame 89 is a substantially rectangular shape, and is an outer discharge determination frame located on the outermost side among the plurality of discharge determination frames. The maximum discharge determination frame 89 corresponds to the maximum range in which the processing liquid discharged from the discharge head 31 may be deposited on the substrate 9. The maximum discharge determination frame 89 is set based on the position of the outer peripheral portion of the maximum range, the positions of the plurality of outer peripheral discharge ports 314e, and the position of the light existing surface, similarly to the discharge determination frame 88 in the protective liquid film. The The setting order of the normal discharge determination frame 85, the oblique discharge determination frame 87, the in-protection liquid film discharge determination frame 88, and the maximum discharge determination frame 89 may be changed as appropriate.

  When the setting of each discharge determination frame (that is, normal discharge determination frame 85, oblique discharge determination frame 87, protective liquid film discharge determination frame 88 and maximum discharge determination frame 89) is completed, the determination unit 75 causes each discharge determination frame to Information indicating whether or not the bright spot 81 is present, that is, information indicating whether or not the bright spot 81 is present in each ejection determination frame is acquired. The determination unit 75 determines that the bright spot 81 exists in the discharge determination frame if at least a part of the bright spot 81 is located in the discharge determination frame. Further, when the bright spot 81 is located across the two inner and outer discharge determination frames, it is determined that the bright spot 81 does not exist in the outer discharge determination frame but exists in the inner discharge determination frame. The For example, when the bright spot 81 is located across the normal discharge determination frame 85 and the oblique discharge determination frame 87, it is determined that the bright spot 81 is not in the oblique discharge determination frame 87 but in the normal discharge determination frame 85. The On the other hand, when at least a part of the bright spot 81 exists in a region excluding the normal discharge determination frame 85 in the oblique discharge determination frame 87 and the entire bright spot 81 is located outside the normal discharge determination frame 85, It is determined that the bright spot 81 exists in the oblique discharge determination frame 87. The same applies to the presence / absence of the bright spot 81 in the protective liquid in-film discharge determination frame 88 and the maximum discharge determination frame 89.

  In the acquisition of the presence / absence information of the bright spot 81 in the determination unit 75, first, the presence / absence information of the bright spot 81 in each normal ejection determination frame 85 is acquired. Specifically, one bright spot 81 is detected as the target bright spot on the inspection image 8. Subsequently, as the normal discharge determination frame 85 and the oblique discharge determination frame 87 corresponding to the target bright spot, the normal discharge determination frame 85 and the diagonal discharge determination frame 87 that are located closest to the target bright spot are extracted.

  Then, the position of the noticeable luminescent spot is compared with the extracted positions of the normal ejection determination frame 85 and the oblique ejection judgment frame 87, whether or not the noticeable luminescent spot exists in the normal ejection judgment frame 85, and It is determined whether or not it exists in the oblique discharge determination frame 87. As described above, the determination unit 75 determines that the target bright spot exists in the normal discharge determination frame 85 if at least a part of the target bright spot is located in the normal discharge determination frame 85. Further, if the entire noticeable luminescent spot is located outside the normal discharge determination frame 85 and at least a part of the noticeable luminescent spot is located within the oblique discharge determination frame 87, the noticeable luminescent spot is determined to be in the oblique discharge determination frame 87. 87 is determined to exist.

  On the other hand, when it is determined that the target bright spot does not exist in the normal discharge determination frame 85 and the oblique discharge determination frame 87, the position of the target bright spot and the position of the discharge determination frame 88 in the protective liquid film are compared, and the target bright spot is compared. It is determined whether or not a point exists in the protective liquid film discharge determination frame 88. If at least a part of the target bright spot is located in the protective liquid film discharge determination frame 88, it is determined that the target bright spot exists in the protective liquid film discharge determination frame 88. When it is determined that the target bright spot does not exist within the protective liquid film discharge determination frame 88, the position of the target bright spot and the position of the maximum discharge determination frame 89 are compared, and the target bright spot is within the maximum discharge determination frame 89. It is determined whether or not it exists. If at least a part of the target bright spot is located in the maximum discharge determination frame 89, it is determined that the target bright spot exists in the maximum discharge determination frame 89.

  When the determination unit 75 determines whether or not the bright spot 81 is present, an area outside the maximum ejection determination frame 89 in the inspection image 8 is excluded from the target area for the bright spot detection. Thus, the maximum ejection determination frame 89 serves as a bright spot detection mask that masks the outer region. As a result, the time required for the bright spot detection by the determination unit 75 can be shortened, and the time required for the quality determination of the ejection operation by the ejection inspection unit 5 can be shortened.

  The inspection calculation unit 73 is based on the presence / absence information of the bright spot 81 in each normal discharge determination frame 85, each oblique discharge determination frame 87, in the protective liquid film discharge determination frame 88 and in the maximum discharge determination frame 89. The determination unit 75 determines whether the discharge operation at the discharge ports 314a to 314d corresponding to each normal discharge determination frame 85 is good or bad. For a specific example of the quality determination of the discharge operation, see FIG. A through FIG. This will be described below with reference to E.

  FIG. A through FIG. E is a diagram conceptually showing a part of the inspection image 8. FIG. A through FIG. In E, a plurality of normal discharge determination frames 85 in a part of the first normal discharge determination frame row 86a, a plurality of oblique discharge determination frames 87 corresponding to the plurality of normal discharge determination frames 85, and an in-protection liquid film discharge determination A part of the frame 88, a part of the maximum discharge determination frame 89, and a bright spot 81 are shown. FIG. A thru | or FIG. The same applies to E.

  FIG. In the case of A, there is information that one bright spot 81 exists inside each of the five normal ejection determination frames 85, and information that no bright spot 81 exists in the area outside each normal ejection determination frame 85. The determination unit 75 acquires the presence / absence information of the bright spot 81. Then, based on the presence / absence information, it is determined that the discharge operation at the five first discharge ports 314a corresponding to the five normal discharge determination frames 85 is good (that is, normal).

  FIG. In the case of B, the bright spot 81 does not exist in the first normal discharge determination frame 85 from the left side in the drawing, and one bright spot 81 exists in each of the other four normal discharge determination frames 85. And the information that one bright spot 81 exists in the first oblique discharge determination frame 87 from the left side is acquired by the determination unit 75 as the presence / absence information of the bright spot 81. Further, information indicating that the bright spot 81 does not exist in the protective liquid film discharge determination frame 88 and the maximum discharge determination frame 89 is also acquired by the determination unit 75 as the presence / absence information of the bright spot 81.

  Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good. Further, for the first discharge port 314a corresponding to the first normal discharge determination frame 85 from the left side, since the bright spot 81 corresponding to the first discharge port 314a exists in the oblique discharge determination frame 87, the processing liquid However, it is determined that there is a discharge failure (so-called oblique discharge) in which the discharge is shifted from the normal discharge range. The occurrence of a discharge failure is notified from the determination unit 75 to an operator or the like through a notification unit 79 (see FIG. 4) such as a monitor of the discharge inspection unit 5. Then, maintenance of the discharge head 31 such as cleaning of the discharge port 314a is performed before processing for the substrate 9 scheduled thereafter.

  FIG. In the case of C, the bright spot 81 does not exist in the first normal discharge determination frame 85 and the oblique discharge determination frame 87 from the left side in the figure, and one in each of the other four normal discharge determination frames 85. Information that the bright spot 81 exists and information that one bright spot 81 exists in the discharge determination frame 88 within the protective liquid film are acquired by the determination unit 75 as presence / absence information of the bright spot 81. Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good.

  For the first discharge ports 314a corresponding to the first normal discharge determination frame 85 and the diagonal discharge determination frame 87 from the left side, the bright spot 81 does not exist in the normal discharge determination frame 85 and the diagonal discharge determination frame 87, and protection is performed. Since the bright spot 81 is present in the vicinity of the oblique discharge determination frame 87 in the in-liquid film discharge determination frame 88, the processing liquid deviates from the oblique discharge range corresponding to the oblique discharge determination frame 87 and is largely obliquely discharged. It is determined that a discharge failure has occurred. Further, it is determined that the processing liquid from the first discharge port 314 a is deposited on the protective liquid film 93 when being discharged onto the substrate 9. Occurrence of the ejection failure is notified from the determination unit 75 to the operator or the like through the notification unit 79, and maintenance of the ejection head 31 is performed.

  In the determination unit 75, the discharge port corresponding to the bright spot 81 in the protective liquid film discharge determination frame 88 may not be specified. In this case, for the first discharge port 314a that is the first from the left side, either a large oblique discharge out of the range corresponding to the oblique discharge determination frame 87, or a non-discharge failure due to clogging of the discharge port or the like occurs. It is determined that Further, the protective liquid film 93 is formed outside the region corresponding to the oblique discharge determination frame 87 from the first discharge port 314a from the left side and any one of the other discharge ports 314a to 314d (not shown). It is determined that a large oblique discharge that has landed on the surface occurs.

  FIG. In the case of D, the bright spot 81 does not exist in the first normal discharge determination frame 85 and the oblique discharge determination frame 87 from the left side in the figure, and one in each of the other four normal discharge determination frames 85. Information that the bright spot 81 exists, information that the bright spot 81 does not exist in the protective liquid film discharge determination frame 88, and information that one bright spot 81 exists in the maximum discharge determination frame 89, The determination unit 75 acquires the presence / absence information of the bright spot 81. Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good.

  For the first discharge port 314a corresponding to the first normal discharge determination frame 85 from the left side, the bright spot 81 does not exist in the normal discharge determination frame 85 and the oblique discharge determination frame 87 corresponding to the first discharge port 314a. In addition, since the bright spot 81 does not exist in the discharge determination frame 88 in the protective liquid film and the bright spot 81 exists in the maximum discharge determination frame 89, the processing liquid is discharged with a great deviation from the discharge direction. It is determined that the liquid is applied to the outside of the protective liquid film 93 when discharged onto the substrate 9. The occurrence of a discharge failure is notified from the determination unit 75 to an operator or the like through a notification unit 79 such as a monitor of the discharge inspection unit 5. If the processing liquid is deposited on the substrate 9 outside the protective liquid film 93, the pattern on the substrate 9 may be damaged. For example, the discharge head 31 is subjected to disassembly maintenance or other discharge heads 31. Will be replaced.

  The determination unit 75 does not have to specify the discharge port corresponding to the bright spot 81 in the maximum discharge determination frame 89. In this case, for the first discharge port 314a from the left side, it is determined that either a very large oblique discharge to the outside of the protective liquid film 93 or a discharge failure of non-discharge has occurred. In addition, a very large oblique discharge is generated to the outside of the protective liquid film 93 from the first discharge port 314a from the left side and any one of the other discharge ports 314a to 314d (not shown). It is determined that

  FIG. In the case of E, the bright spot 81 does not exist in the first normal discharge determination frame 85 and the oblique discharge determination frame 87 from the left side in the figure, and one in each of the other four normal discharge determination frames 85. Information indicating that the bright spot 81 exists and information indicating that the bright spot 81 does not exist in the protective liquid film discharge determination frame 88 and the maximum discharge determination frame 89 are acquired by the determination unit 75 as presence / absence information of the bright spot 81. Is done. Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good. In addition, it is determined that a non-ejection failure in which the processing liquid is not ejected has occurred at the first ejection port 314a corresponding to the first normal ejection determination frame 85 from the left side.

  By the way, as a discharge inspection unit that determines the quality of the discharge operation at a plurality of discharge ports, it is possible to acquire an inspection image similar to the above and measure the interval in the arrangement direction of a plurality of bright spots on the inspection image. In such a discharge inspection unit (hereinafter referred to as “comparative example discharge inspection unit”), the discharge operation at each discharge port is determined to be good if the intervals between the plurality of bright spots are approximately equal to a predetermined interval. On the other hand, when the interval between two adjacent bright spots is at least twice as large as the predetermined interval, it is determined that a non-discharge outlet exists between the two outlets corresponding to the two bright spots.

  In the discharge inspection unit of the comparative example, when there are two adjacent bright spots that are larger (or smaller) than the predetermined gap by a certain amount, either one of the two discharge openings corresponding to the two bright spots Alternatively, it is determined that an ejection failure of oblique ejection has occurred on both sides. However, it is not easy to determine which of the two discharge ports has a discharge failure. In addition, when the processing liquid from one discharge port is shifted away from the other discharge port and the processing liquid from the other discharge port is shifted away from one discharge port, the processing liquid from each discharge port Even if the deviation is within the allowable range, as described above, at least one of the two discharge ports is erroneously determined as a discharge failure. Further, when a discharge failure occurs in a plurality of continuous discharge ports, and the plurality of bright spots corresponding to the plurality of discharge ports are shifted by the same distance in the same direction, the interval between the plurality of bright spots is a predetermined interval. Since they are approximately equal, these ejection defects are not detected.

  On the other hand, in the discharge inspection unit 5 of the substrate processing apparatus 1, the determination frame setting unit 74 sets a plurality of normal discharge determination frames 85 respectively corresponding to the plurality of discharge ports 314 a to 314 d on the inspection image 8. Then, the presence / absence information of the bright spot 81 in each normal discharge determination frame 85 is acquired by the determination unit 75, and the quality of the discharge operation at the discharge ports 314a to 314d corresponding to each normal discharge determination frame 85 is determined based on the presence / absence information. Is determined. Thereby, the quality of the discharge operation in each of the plurality of discharge ports 314a to 314d can be accurately determined individually (that is, independently of the quality of the discharge operations of the other discharge ports 314a to 314d).

  In the discharge inspection unit 5, the determination frame setting unit 74 sets a plurality of oblique discharge determination frames 87 respectively corresponding to the plurality of discharge ports 314 a to 314 d on the inspection image 8. Then, the presence / absence information of the bright spot 81 in each oblique discharge determination frame 87 is acquired by the determination unit 75, and the occurrence of oblique discharge at the discharge ports 314a to 314d corresponding to each oblique discharge determination frame 87 based on the presence / absence information. The presence or absence of is determined. As a result, it is possible to individually and accurately determine the oblique discharge at the plurality of discharge ports 314a to 314d, more specifically, the light oblique discharge into the region corresponding to the oblique discharge determination frame 87.

  Further, in the discharge inspection unit 5, the determination frame setting unit 74 sets a protective liquid film discharge determination frame 88 corresponding to the protective liquid film 93 on the inspection image 8. Then, the presence / absence information of the bright spot 81 in the protective liquid film discharge determination frame 88 is acquired by the determination unit 75, and the protective liquid film 93 is outside the region corresponding to the oblique discharge determination frame 87 based on the presence / absence information. Whether or not a larger oblique discharge has occurred in the region where is formed is detected. As a result, it is possible to accurately determine the occurrence of a larger oblique discharge.

  When the thickness of the protective liquid film 93 is smaller than a predetermined thickness on the outer periphery of the protective liquid film 93 formed on the substrate 9, the reference is set when the above-described protective liquid film discharge determination frame 88 is set. The outer peripheral portion of the protective liquid film 93 may be an outer peripheral edge of a portion of the protective liquid film 93 having a predetermined thickness. Thereby, it is determined whether the processing liquid ejected greatly deviating from the ejection direction has landed on the part having the predetermined thickness of the protective liquid film 93 or has landed on the area outside the part. Can do.

  In the discharge inspection unit 5, the determination frame setting unit 74 sets the maximum discharge determination frame 89 surrounding the protective liquid film discharge determination frame 88 on the inspection image 8. Then, presence / absence information of the bright spot 81 in the maximum discharge determination frame 89 is acquired by the determination unit 75, and occurrence of a very large oblique discharge outside the region where the protective liquid film 93 is formed based on the presence / absence information. The presence or absence of is detected. As a result, it is possible to accurately determine the occurrence of the oblique discharge that reaches the outside of the protective liquid film 93.

  In the ejection inspection unit 5, the imaging direction in the imaging unit 52 is inclined with respect to a plane perpendicular to the predetermined ejection direction of the processing liquid from the ejection head 31. Thereby, it is possible to suppress the plurality of bright spots 81 from overlapping each other on the inspection image 8. Further, it is possible to suppress the plurality of normal ejection determination frames 85 from overlapping each other on the inspection image 8 and to suppress the plurality of oblique ejection determination frames 87 from overlapping each other. As a result, it is possible to improve the pass / fail judgment accuracy of the discharge operation at the plurality of discharge ports 314a to 314d. Such a structure of the discharge inspection unit 5 is particularly suitable for determining whether the discharge operation is good or not in a discharge head having a plurality of discharge port arrays arranged in parallel to each other.

  As described above, in the discharge inspection unit 5, the light existence surface is inclined with respect to a plane perpendicular to the predetermined discharge direction of the processing liquid. Thereby, it is possible to suppress the plurality of bright spots 81, the plurality of normal ejection determination frames 85, and the plurality of oblique ejection determination frames 87 from overlapping each other on the inspection image 8. As a result, it is possible to further improve the pass / fail judgment accuracy of the discharge operation at the plurality of discharge ports 314a to 314d. Such a structure of the discharge inspection unit 5 is also particularly suitable for determining whether the discharge operation is good or not in a discharge head having a plurality of discharge port arrays arranged in parallel to each other.

  In the above-described example, the case where the same number of the oblique discharge determination frames 87 as the normal discharge determination frames 85 is set is described. However, as illustrated in FIG. 10, a plurality of normal discharge determination frames are determined by the determination frame setting unit 74. A relatively large oblique ejection determination frame 87 a with 85 positioned inside may be set on the inspection image 8. In the example shown in FIG. 10, the periphery of a plurality of normal discharge determination frames 85 (that is, the first normal discharge determination frame row 86a) corresponding to all the first discharge ports 314a (see FIG. 3) of the first discharge port row 313a. In addition, one oblique ejection determination frame 87a having a substantially rectangular shape is set. In addition, an oblique discharge determination frame having a shape substantially similar to the oblique discharge determination frame 87a around each of the second normal discharge determination frame row 86b, the third normal discharge determination frame row 86c, and the fourth normal discharge determination frame row 86d. 87a is set. The position of each oblique discharge determination frame 87a on the inspection image 8 is set based on the position of the corresponding normal discharge determination frame row. A protective liquid film discharge determination frame 88 similar to the above is set around the four oblique discharge determination frames 87a, and a maximum discharge determination frame which is an outer discharge determination frame around the protective liquid film discharge determination frame 88. 89 is set.

  In the inspection calculation unit 73, based on the presence / absence information of the bright spot 81 in each normal discharge determination frame 85, the oblique discharge determination frame 87a, the protective liquid film discharge determination frame 88, and the maximum discharge determination frame 89, as described above. The determination unit 75 determines whether the discharge operation at the discharge ports 314a to 314d corresponding to each normal discharge determination frame 85 is good or bad. For a specific example of quality determination of the discharge operation, see FIG. A thru | or FIG. This will be described below with reference to E.

  FIG. In the case of A, FIG. As in A, information that one bright spot 81 exists inside each of the five normal ejection determination frames 85, and information that no bright spot 81 exists in the area outside each normal ejection determination frame 85. Is acquired by the determination unit 75 as the presence / absence information of the bright spot 81. Then, based on the presence / absence information, it is determined that the discharge operation at the five first discharge ports 314a corresponding to the five normal discharge determination frames 85 is good (that is, normal).

  FIG. In the case of B, the bright spot 81 does not exist in the first normal discharge determination frame 85 from the left side in the drawing, and one bright spot 81 exists in each of the other four normal discharge determination frames 85. And the information that one bright spot 81 exists in the oblique ejection determination frame 87a is acquired by the determination unit 75 as the presence / absence information of the bright spot 81. In addition, the bright spot 81 in the oblique discharge determination frame 87a is located in the vicinity of the first normal discharge determination frame 85 from the left side, and in the protective liquid film discharge determination frame 88 and the maximum discharge determination frame 89. Information that the bright spot 81 does not exist is also acquired by the determination unit 75 as the presence / absence information of the bright spot 81.

  Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good. For the first discharge port 314a corresponding to the first normal discharge determination frame 85 from the left side, the bright spot 81 does not exist in the normal discharge determination frame 85, and the vicinity of the normal discharge determination frame 85. Since there is one bright spot 81 in the oblique discharge determination frame 87a, it is determined that there is a discharge failure (so-called oblique discharge) in which the processing liquid is discharged out of the normal discharge range. Occurrence of a discharge failure is notified from the determination unit 75 to an operator or the like through a notification unit 79 such as a monitor of the discharge inspection unit 5, and maintenance of the discharge head 31 is performed.

  In the determination unit 75, the discharge port corresponding to the bright spot 81 in the oblique discharge determination frame 87a may not be specified. In this case, with respect to the first first discharge port 314a from the left side, it is determined that one of the ejection failures of oblique ejection and non-ejection has occurred. In addition, it is determined that oblique discharge is occurring from any one of the first discharge ports 313a to the region corresponding to the diagonal discharge determination frame 87a.

  FIG. In the case of C, the bright spot 81 does not exist in the first normal discharge determination frame 85 from the left side in the drawing, and one bright spot 81 exists in each of the other four normal discharge determination frames 85. Information that the bright spot 81 does not exist in the oblique discharge determination frame 87a and the maximum discharge determination frame 89, and information that one bright spot 81 exists in the protective liquid film discharge determination frame 88, The determination unit 75 acquires the presence / absence information of the bright spot 81. Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good.

  For the first discharge port 314a corresponding to the first normal discharge determination frame 85 from the left side, the bright spot 81 does not exist in the normal discharge determination frame 85 corresponding to the first discharge port 314a, and the oblique discharge determination frame 87a. Since the bright spot 81 does not exist in the inside, and the bright spot 81 exists in the vicinity of the normal discharge determination frame 85 in the protective liquid film discharge determination frame 88, the processing liquid corresponds to the oblique discharge determination frame 87a. It is determined that there is an ejection failure that deviates largely from the range of oblique ejection and that is largely obliquely ejected. Further, it is determined that the processing liquid from the first discharge port 314 a is deposited on the protective liquid film 93 when being discharged onto the substrate 9. Occurrence of a discharge failure is notified from the determination unit 75 to an operator or the like through a notification unit 79 such as a monitor of the discharge inspection unit 5, and maintenance of the discharge head 31 is performed.

  In the determination unit 75, the discharge port corresponding to the bright spot 81 in the protective liquid film discharge determination frame 88 may not be specified. In this case, with respect to the first first discharge port 314a from the left side, it is determined that either a large oblique discharge out of the range corresponding to the oblique discharge determination frame 87a or a non-discharge failure occurs. . In addition, the first liquid discharge port 314a and any one of the other discharge ports 314a to 314d (not shown) are large and land on the protective liquid film 93 outside the region corresponding to the oblique discharge determination frame 87a. It is determined that oblique ejection has occurred.

  FIG. In the case of D, the bright spot 81 does not exist in the first normal discharge determination frame 85 from the left side in the drawing, and one bright spot 81 exists in each of the other four normal discharge determination frames 85. Information that the bright spot 81 does not exist in the oblique discharge determination frame 87a and the protective liquid film discharge determination frame 88, and information that one bright spot 81 exists in the maximum discharge determination frame 89, The determination unit 75 acquires the presence / absence information of the bright spot 81. Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good.

  For the first discharge port 314a corresponding to the first normal discharge determination frame 85 from the left side, the normal discharge determination frame 85, the oblique discharge determination frame 87a, and the protective liquid film discharge determination frame 88 corresponding to the first discharge port 314a. Since the bright spot 81 does not exist in the inside, and the bright spot 81 exists in the maximum discharge determination frame 89, the processing liquid is discharged with a great deviation from the discharge direction and is protected when discharged onto the substrate 9. It is determined that the liquid is deposited outside the liquid film 93. The occurrence of a discharge failure is notified from the determination unit 75 to an operator or the like through a notification unit 79 such as a monitor of the discharge inspection unit 5, and the discharge head 31 is, for example, disassembled and maintained or replaced with another discharge head 31. .

  The determination unit 75 does not have to specify the discharge port corresponding to the bright spot 81 in the maximum discharge determination frame 89. In this case, for the first discharge port 314a from the left side, it is determined that either a very large oblique discharge to the outside of the protective liquid film 93 or a discharge failure of non-discharge has occurred. In addition, it is determined that a very large oblique discharge is generated from the first discharge port 314a and any one of the other discharge ports 314a to 314d (not shown) to the outside of the protective liquid film 93. .

  FIG. In the case of E, the bright spot 81 does not exist in the first normal discharge determination frame 85 from the left side in the drawing, and one bright spot 81 exists in each of the other four normal discharge determination frames 85. And the information that the bright spot 81 does not exist in the oblique discharge determination frame 87a, the protective liquid film discharge determination frame 88, and the maximum discharge determination frame 89 is acquired by the determination unit 75 as the presence / absence information of the bright spot 81. Is done. Based on the presence / absence information, the determination unit 75 determines that the discharge operations at the four first discharge ports 314a corresponding to the second to fifth normal discharge determination frames 85 from the left are good. In addition, it is determined that a non-ejection failure in which the processing liquid is not ejected has occurred at the first ejection port 314a corresponding to the first normal ejection determination frame 85 from the left side.

  Thus, even when one oblique discharge determination frame 87a is set around the plurality of normal discharge determination frames 85, the determination unit 75 causes the bright spot 81 in each normal discharge determination frame 85 to be similar to the above. Presence / absence information is acquired, and based on the presence / absence information, the quality of the discharge operation at the discharge ports 314a to 314d corresponding to each normal discharge determination frame 85 is determined. Thereby, the quality of the discharge operation in each of the plurality of discharge ports 314a to 314d can be individually and accurately determined.

  Further, the ejection inspection unit 5 acquires the presence / absence information of the bright spot 81 in each oblique ejection determination frame 87a, and based on the presence / absence information, the obliqueness in the ejection port arrays 313a to 313d respectively corresponding to each oblique ejection determination frame 87a. The presence or absence of occurrence of discharge is determined. Thereby, it is possible to accurately determine the oblique discharge at the plurality of discharge ports 314a to 314d. The oblique discharge determination frame 87a may be set so as to surround two or more discharge port arrays.

  In the substrate processing apparatus 1, when the ejection head 31 moves to the inspection position, there is a possibility that the substrate processing apparatus 1 is arranged slightly deviated from the designed inspection position. When the inspection position of the ejection head 31 is shifted, the relative positions of the light emitting unit 51 and the imaging unit 52 with respect to the ejection head 31 are also shifted. The positions of the normal discharge determination frame 85, the oblique discharge determination frame 87, the protective liquid film discharge determination frame 88, and the maximum discharge determination frame 89 on the inspection image 8 are based on the assumption that the discharge head 31 is positioned at the designed inspection position. Therefore, when the inspection position of the ejection head 31 is shifted, the positional relationship on the inspection image 8 between the plurality of bright spots 81 of the processing liquid ejected from the ejection head 31 and each ejection determination frame also changes. As a result, although the processing liquid is normally ejected in a predetermined ejection direction, the bright spot 81 is outside the normal ejection determination frame 85, and there is a possibility that the ejection abnormality is determined.

  Therefore, in the substrate processing apparatus 1, when setting of each ejection determination frame by the determination frame setting unit 74 when there is a concern about the displacement of the inspection position of the ejection head 31, the actual bright spot 81 on the inspection image 8 is set. Based on the position, the positions of the plurality of normal ejection determination frames 85 may be set. Specifically, first, among the plurality of bright spots 81 corresponding to the first ejection port array 313a included in the inspection image 8, the positions (that is, the coordinates) of the two bright spots 81 located at both ends are located. ) Is required. Subsequently, the positions of the two normal ejection determination frames 85 are set so that the two bright spots 81 are respectively located at the centers.

  Since the plurality of bright spots 81 corresponding to the first discharge port array 313a are arranged in a straight line if the designed discharge is performed, a plurality of normal discharge determination frames 85 corresponding to the first discharge port array 313a. Are also arranged on a straight line. Therefore, a plurality of normal discharge determination frames 85 are arranged between the two normal discharge determination frames 85 so as to be arranged in a straight line. The interval on the inspection image 8 of the bright spots 81 of the processing liquid discharged from the adjacent first discharge ports 314a decreases as the distance from the imaging unit 52 that is the observation viewpoint increases (that is, from the near side to the far side). Therefore, the interval between the plurality of normal ejection determination frames 85 also needs to be reduced as the distance from the imaging unit 52 increases. The positions of the plurality of normal discharge determination frames 85 are predetermined, for example, as an interval between two adjacent normal discharge determination frames 85 (for example, an interval between the centers of the normal discharge determination frames 85) moves from the near side to the back side. The distance is set to be shorter.

  Alternatively, in the three-dimensional coordinate system set in the substrate processing apparatus 1, the plurality of bright spot reference positions corresponding to the plurality of first discharge ports 314a (that is, the bright spot 81 when the processing liquid is discharged as designed). The coordinates of the position at which are formed) are obtained. Subsequently, it passes through a bright spot reference position (hereinafter referred to as “first end position”) corresponding to the first discharge port 314 a located at one end of the first discharge port array 313 a and is imaged by the imaging unit 52. The coordinates of the bright spot projection position, which is the position when a plurality of bright spot reference positions are projected on a virtual plane perpendicular to the axis J2, is obtained.

  The projection of each bright spot reference position is performed in a direction from each bright spot reference position toward the start point of the imaging axis J2 (that is, the center of the end surface on the objective side of the optical system of the imaging unit 52). The calculation of the coordinates of each bright spot projection position is, for example, the brightness corresponding to the start point of the imaging axis J2, the first end position, and the first discharge port 314a located at the other end of the first discharge port array 313a. Based on the triangle connecting the second end position, which is the point projection position, and the straight line connecting the first end position and the second end position, this is performed using the Menelaus theorem. Then, according to the ratio of the interval between each two adjacent bright spot projection positions to the distance between the first end position and the second end position, on the inspection image 8, the above two normal A plurality of normal discharge determination frames 85 are arranged between the discharge determination frames 85 (that is, two normal discharge determination frames 85 corresponding to the first discharge ports 314a at both ends).

  Thus, in the determination frame setting unit 74, the positions of the plurality of normal discharge determination frames 85 corresponding to the first discharge port array 313a are bright spots corresponding to the first discharge ports 314a at both ends of the first discharge port array 313a. It is set on the basis of 81 positions on the inspection image 8. The positions of the plurality of normal discharge determination frames 85 corresponding to the second discharge port row 313b, the third discharge port row 313c, and the fourth discharge port row 313d are also the plurality of normal discharges corresponding to the first discharge port row 313a. It is set similarly to the position setting of the determination frame 85. Thereby, even if the inspection position of the ejection head 31 is deviated from the designed inspection position, it is possible to determine the quality of the ejection operation at the plurality of ejection ports 314a to 314d with high accuracy.

  As described above, when the positions of the plurality of normal ejection determination frames 85 are set based on the positions of the bright spots corresponding to the ejection ports at both ends of each ejection port array, the periphery of each normal ejection determination frame 85 is surrounded. The position of the oblique discharge determination frame 87 (see FIG. 7) is set based on the position of each normal discharge determination frame 85. On the other hand, the positions of the oblique discharge determination frames 87a (see FIG. 10) surrounding the plurality of normal discharge determination frames 85 are set based on the positions of the normal discharge determination frames 85 at both ends of each normal discharge determination frame row. The positions of the in-protective-film discharge determination frame 88 and the maximum discharge determination frame 89 are set based on the positions of the normal discharge determination frame 85 and the oblique discharge determination frames 87 and 87a.

  In the substrate processing apparatus 1, when the distance between the imaging unit 52 and the processing liquid is different, the size of the bright spot 81 on the inspection image 8, that is, the apparent size of the bright spot 81 also changes. For example, the apparent size of the bright spot 81 far from the imaging unit 52 is smaller than that of the bright spot 81 close to the imaging unit 52, and the apparent movement amount of the bright spot 81 due to the oblique ejection is also reduced. Therefore, in the determination of the presence / absence of the bright spot 81 in the discharge determination frame such as the normal discharge determination frame 85, the bright spot 81 far from the imaging unit 52 is captured even if it is shifted from the bright spot reference position by the oblique discharge. Compared to the bright spot 81 close to the portion 52, it is easier to determine that the pixel exists within the ejection determination frame.

  On the other hand, since the apparent size of the bright spot 81 close to the imaging unit 52 is larger than the bright spot 81 far from the imaging unit 52, even if the center of gravity of the bright spot 81 is located outside the ejection determination frame, There is a high possibility that a part of the bright spot 81 is located within the ejection determination frame. As a result, when the center of gravity is located outside the ejection determination frame, the bright spot 81 close to the imaging unit 52 is more easily determined to be present in the ejection determination frame than the bright spot 81 far from the imaging unit 52.

  Further, in the substrate processing apparatus 1, some of the bright spots 81 out of the focus range 80 of the imaging section 52 are outside the focusing range 80 depending on the arrangement of the ejection head 31, the light emitting section 51, and the imaging section 52. Located in. In this case, the part of the bright spots 81 are blurred (so-called out of focus) on the inspection image 8 and greatly spread compared to the bright spots 81 in the focusing range 80. Since there is a high possibility that part of the bright spots 81 that are greatly spread are located within the discharge determination frame, other bright spots are determined in the presence / absence determination of the bright spots 81 in the discharge determination frames such as the normal discharge determination frame 85. Compared to 81, it is easier to determine that it is within the discharge determination frame.

  Therefore, the discharge inspection unit 5 performs adjustment to reduce the influence on the quality determination of the discharge operation due to the distance between the imaging unit 52 and the bright spot 81 and the blur of the bright spot 81 outside the focusing range 80. Is called. Below, the two methods of the said adjustment are demonstrated. In the first adjustment method, the size of the normal discharge determination frame 85 is adjusted when the normal discharge determination frame 85 is set by the determination frame setting unit 74. In the second adjustment method, the size of the bright spot 81 on the inspection image 8 is corrected before the determination unit 75 determines the quality of the ejection operation.

  In the first adjustment method, first, a plurality of normal discharge determination frames of the same shape respectively corresponding to the plurality of discharge ports 314a to 314d are obtained by the temporary setting unit 77 (see FIG. 4) of the determination frame setting unit 74 as shown in FIG. As shown in FIG. 5, the inspection image 8 is temporarily set around the plurality of bright spot reference positions described above. Each normal discharge determination frame (hereinafter referred to as “temporary setting frame 850”) temporarily set by the temporary setting unit 77 is a substantially rectangular shape having a predetermined size. In FIG. 12, after adjustment by a frame size adjustment unit 78 described later, a first normal discharge determination frame row 86a, a second normal discharge determination frame row 86b, a third normal discharge determination frame row 86c, and a fourth normal discharge determination frame row 86d In the four temporary setting frame rows 860a to 860d, the temporary setting frame 850 located on the left side in the drawing is close to the imaging unit 52, and the temporary setting frame 850 located on the right side is far from the imaging unit 52. In FIG. 12, only the bright spot 81 and the temporarily set normal discharge determination frame are drawn, and other discharge determination frames such as an oblique discharge determination frame are not shown. The same applies to FIGS. 13 to 16 described later.

  Subsequently, for each temporary setting frame 850, the frame size adjustment unit 78 obtains an inspection distance that is a distance between the starting point of the imaging axis J2 of the imaging unit 52 and the bright spot reference position corresponding to each temporary setting frame 850. It is done. Then, the temporarily set frame 850 is adjusted based on the inspection distance by the apparent frame size adjusting unit 78a of the frame size adjusting unit 78. Specifically, the temporary setting frame 850 is adjusted so as to decrease as the inspection distance increases. More specifically, a predetermined function of the inspection distance that decreases as the inspection distance of the temporary setting frame 850 to be noticed increases as the frame reduction ratio, and the center position (that is, the bright spot reference position) of each temporary setting frame 850 is determined. Each temporary setting frame 850 is adjusted as shown in FIG. 13 by multiplying the lengths of the four sides of each temporary setting frame 850 by the frame reduction ratio without changing. In each temporary setting frame row 860a to 860d, the length of each side of the temporary setting frame 850 becomes shorter from the left side to the right side in the drawing. The function is “1” when the inspection distance is equal to the distance between the bright spot reference position closest to the imaging unit 52 and the imaging unit 52, for example, and is less than 1 when the inspection distance is larger than the distance. Is set to be

  Next, the size of each temporary setting frame 850 adjusted by the process described with reference to FIG. 13 by the focus shift frame size adjusting unit 78b of the frame size adjusting unit 78 is the same as the in-focus distance and each temporary setting of the imaging unit 52. Further adjustment is made so that the difference from the inspection distance corresponding to the setting frame 850 (hereinafter referred to as “the amount of defocus”) increases, and the normal ejection determination frame 85 is set. Specifically, a predetermined function of the defocus amount that increases as the defocus amount increases is used as a blur amount, and the four positions of each temporary setting frame 850 are changed without changing the center position of each temporary setting frame 850. By subtracting the blur amount from the length, each normal ejection determination frame 85 is set as shown in FIG.

  In the example shown in FIGS. 12 to 14, a bright spot 81 located near the center in the vertical direction in the drawing is included in the focusing range 80. Therefore, the temporary setting frame 850 on the right side of the temporary setting frame rows 860a and 860b on the upper side (that is, the front side in the three-dimensional coordinate system) in FIG. 13 is normally ejected without being changed in size. A frame 85 is used. Further, the other temporarily set frames 850 of the temporarily set frame rows 860a and 860b are reduced by subtracting the blur amount from each side. As shown in FIG. 14, in the temporary setting frame rows 860a and 860b (that is, the first normal discharge determination frame row 86a and the second normal discharge determination frame row 86b), the amount of blur subtracted from each temporary setting frame 850 is The size increases from the right side to the left side in the figure.

  On the other hand, in the lower temporary setting frame rows 860c and 860d in FIG. 13, the left temporary setting frames 850 are set as normal ejection determination frames 85 without changing their sizes. Further, the other temporarily set frames 850 of the temporarily set frame rows 860c and 860d are reduced by subtracting the blur amount from each side. As shown in FIG. 14, in the temporary setting frame rows 860c and 860d (that is, the third normal discharge determination frame row 86c and the fourth normal discharge determination frame row 86d), the blur amount subtracted from each temporary setting frame 850 is The size increases from the left side to the right side in the figure.

  Similarly to the adjustment related to the normal discharge determination frame 85 described above, the oblique discharge determination frame 87 corresponding to each bright spot reference position is temporarily set on the inspection image 8 by the temporary setting unit 77 and larger by the frame size adjustment unit 78. Is adjusted.

  In the substrate processing apparatus 1, the quality determination of the discharge operation at each of the discharge ports 314 a to 314 d is performed based on the presence / absence information of the bright spot 81 in the normal discharge determination frame 85 whose size is adjusted as described above. In the adjustment of the normal ejection determination frame 85, as described above, the adjustment for reducing each temporary setting frame 850 is performed as the inspection distance corresponding to each temporary setting frame 850 increases. As a result, the influence of the distance between the imaging unit 52 and the bright spot 81 on the quality determination of the ejection operation can be reduced, and the accuracy of the quality determination of the ejection operation can be improved.

  Further, as the amount of defocus, which is the difference between the inspection distance corresponding to each temporary setting frame 850 and the focusing distance of the imaging unit 52, increases, adjustments are performed to reduce each temporary setting frame 850. Thereby, the influence on the quality determination of the ejection operation due to the blurring of the bright spot 81 outside the focusing range 80 can be reduced, and the accuracy of the quality judgment of the ejection operation can be further improved.

  In the above example, the frame size adjustment unit 78 performs the adjustment by the apparent frame size adjustment unit 78a and the adjustment by the in-focus frame size adjustment unit 78b on each temporary setting frame 850. There is no need to make any adjustments. In the frame size adjustment unit 78, the normal ejection determination frame 85 is set by adjusting each temporary setting frame 850 by at least one of the apparent frame size adjustment unit 78a and the out-of-focus frame size adjustment unit 78b. As a result, as described above, the influence of the distance between the imaging unit 52 and the bright spot 81 on the quality determination of the ejection operation can be reduced, and the accuracy of the quality judgment of the ejection operation can be improved.

  In the above-described example, the correction of the discharge determination frames when the same number of the oblique discharge determination frames 87 as the normal discharge determination frames 85 is set has been described. However, as illustrated in FIG. 10, the inside of one oblique discharge determination frame 87 a. Even when a plurality of normal discharge determination frames 85 are set, the normal discharge determination frames 85 are similarly set.

  Next, the second adjustment method described above will be described. In the second adjustment method, first, the determination frame setting unit 74 causes the plurality of normal discharge determination frames 85 of the same shape respectively corresponding to the plurality of discharge ports 314a to 314d to appear on the inspection image 8 as shown in FIG. Is set around the plurality of bright spot reference positions described above. The normal discharge determination frame 85 has a substantially rectangular shape having a predetermined size.

  Subsequently, the bright spot correction unit 76 obtains an inspection distance that is a distance between the bright spot reference position corresponding to each bright spot 81 of the inspection image 8 and the start point of the imaging axis J2 of the imaging unit 52. Then, the apparent bright spot size adjusting unit 76a corrects the size of each bright spot 81 so that the size of each bright spot 81 decreases as the inspection distance decreases. Specifically, a predetermined function of the inspection distance that becomes smaller as the inspection distance becomes smaller is used as the bright spot reduction rate, and each bright spot 81 is set to the bright spot reduction rate without changing the center of gravity position of each bright spot 81. Thus, the size of each bright spot 81 is corrected as shown in FIG.

  Next, the size of each luminescent spot 81 is determined by the difference between the in-focus distance of the imaging unit 52 and the inspection distance corresponding to each luminescent spot 81 by the out-of-focus luminescent spot size adjusting section 76b of the bright spot correcting section 76. Correction is made to reduce as the amount of defocus increases. Specifically, a predetermined function of the defocus amount that increases as the defocus amount increases becomes the bright spot blur amount, and the vertical and horizontal lengths of each bright spot 81 are changed without changing the barycentric position of each bright spot 81. By subtracting the bright spot blur amount from the above, the size of each bright spot 81 is corrected as shown in FIG.

  In the substrate processing apparatus 1, the presence / absence information of the bright spot 81 whose size is corrected in the normal ejection determination frame 85 (that is, information indicating whether or not at least a part of the corrected bright spot 81 exists) is based on. Thus, the determination unit 75 determines whether the discharge operation at each of the discharge ports 314a to 314d is good or bad. In the correction of the bright spot 81, as described above, as the inspection distance corresponding to each bright spot 81 becomes smaller (that is, as the bright spot reference position corresponding to each bright spot 81 approaches the imaging unit 52), each bright spot 81 is corrected. Correction for reducing the point 81 is performed. Thereby, although most of the bright spots 81 are located outside the normal ejection determination frame 85, only a part of the bright spots 81 is suppressed or prevented from being located in the normal ejection determination frame 85. As a result, the influence of the distance between the imaging unit 52 and the bright spot 81 on the quality determination of the ejection operation can be reduced, and the accuracy of the quality determination of the ejection operation can be improved.

  In addition, as the defocus amount, which is the difference between the inspection distance corresponding to each bright spot 81 and the focusing distance of the imaging unit 52, increases, the correction for reducing each bright spot 81 is performed. Thereby, the influence on the quality determination of the ejection operation due to the blurring of the bright spot 81 outside the focusing range 80 can be reduced, and the accuracy of the quality judgment of the ejection operation can be further improved.

  In the above-described example, the bright spot correction unit 76 performs correction by the apparent bright spot size correction unit 76a and correction by the out-of-focus bright spot size correction unit 76b on each bright spot 81. It is not necessary to perform both corrections. In the bright spot correction unit 76, presence / absence information in the normal ejection determination frame 85 is obtained for each bright spot 81 whose size is corrected by at least one of the apparent bright spot size correction unit 76a and the out-of-focus bright spot size correction unit 78b. Based on the presence / absence information acquired by the determination unit 75, the quality of the discharge operation at each of the discharge ports 314a to 314d is determined. As a result, as described above, the influence of the distance between the imaging unit 52 and the bright spot 81 on the quality determination of the ejection operation can be reduced, and the accuracy of the quality judgment of the ejection operation can be improved.

  In the above-described example, the correction of the bright spot 81 when the same number of the oblique discharge determination frames 87 as the normal discharge determination frames 85 is set has been described. However, as illustrated in FIG. 10, the inside of one oblique discharge determination frame 87a. Even when a plurality of normal ejection determination frames 85 are set, the bright spot 81 is similarly corrected.

  In the substrate processing apparatus 1, when the thickness of the planar light 510 emitted from the light emitting unit 51 increases in the vertical direction, each bright spot 81 in the inspection image 8 acquired by the imaging unit 52 extends in the vertical direction (that is, It increases in the discharge direction (designed treatment liquid). The thickness of the planar light 510 from the light emitting unit 51 is approximately constant in the region irradiated with the processing liquid discharged from the discharge head 31, but the light is emitted from the light emitting unit 51 even within the region. The distance from the position where the thickness of the planar light 510 in the ejection direction is the smallest (that is, the position where the planar light 510 is most narrowed in the vertical direction, hereinafter referred to as the “lightest thinned position”). As the value increases, it increases slightly. For this reason, the bright spot 81 far from the light thinnest position is larger in the vertical direction than the bright spot 81 near the light thinnest position. As a result, in the presence / absence determination of the bright spot 81 in the ejection judgment frame such as the normal ejection judgment frame 85, the bright spot 81 far from the light thinnest position is within the discharge judgment frame compared to the bright spot 81 near the light thinnest position. It becomes easy to determine that it exists.

  Therefore, the discharge inspection unit 5 performs adjustment to reduce the influence on the quality determination of the discharge operation due to the distance between the light thinnest position and the bright spot 81. Below, the two methods of the said adjustment are demonstrated. In order to distinguish from the first and second adjustment methods described above, the two adjustment methods are referred to as a “third adjustment method” and a “fourth adjustment method”, respectively. In the third adjustment method, the size of the normal discharge determination frame 85 is adjusted when the normal discharge determination frame 85 is set by the determination frame setting unit 74. In the fourth adjustment method, the size of the bright spot 81 on the inspection image 8 is corrected before the quality determination of the ejection operation by the determination unit 75.

  In the third adjustment method, light between the start point of the optical axis J1 of the light emitting unit 51 and the bright spot reference position corresponding to each normal ejection determination frame 85 is obtained by the light thickness adjusting unit 78c of the frame size adjusting unit 78. The distance in the direction parallel to the axis J1 (hereinafter referred to as “irradiation distance”) and the distance in the direction parallel to the optical axis J1 between the starting point of the optical axis J1 of the light emitting portion 51 and the light thinnest position (hereinafter referred to as “lighting distance”). The height of each normal discharge determination frame 85 in the vertical direction (that is, the discharge direction in the design of the processing liquid) is adjusted based on a determination frame irradiation distance error that is a difference from the “thinnest light distance”). Is done. Specifically, as the determination frame irradiation distance error related to each normal discharge determination frame 85 increases, each normal discharge determination frame 85 is reduced in the vertical direction. As a result, the influence of the determination frame irradiation distance error on the quality determination of the ejection operation can be reduced, and the accuracy of the quality determination of the ejection operation can be improved.

  In the fourth adjustment method, the light thickness correcting unit 76c of the bright spot correcting unit 76 applies the irradiation distance of each bright spot 81 (that is, the start point of the optical axis J1 of the light emitting unit 51 and the bright spot corresponding to each bright spot 81). The vertical height of each bright spot 81 is adjusted based on the bright spot irradiation distance error, which is the difference between the distance from the point reference position in the direction parallel to the optical axis J1) and the thinnest distance. . Specifically, as the bright spot irradiation distance error related to each bright spot 81 becomes larger, each bright spot 81 is reduced in the vertical direction. As a result, the influence of the bright spot irradiation distance error on the quality determination of the ejection operation can be reduced, and the accuracy of the quality judgment of the ejection operation can be improved.

  The four adjustment methods described above may be implemented in combination as appropriate. For example, the size of the normal ejection determination frame 85 may be adjusted by implementing the first and third adjustment methods. Alternatively, the size of the bright spot 81 may be adjusted by performing the second and fourth adjustment methods. Further, any combination of two or more adjustment methods among the first to fourth adjustment methods may be implemented.

  In the above description, if at least a part of the bright spot 81 is located within the discharge determination frame in the determination of the presence or absence of the bright spot 81 in the discharge determination frame such as the normal discharge determination frame 85 by the determination unit 75, the bright spot 81 is Although it is determined that it exists in the discharge determination frame, it may be determined that the bright spot 81 exists in the discharge determination frame when more than half of the bright spot 81 is located in the discharge determination frame. Alternatively, it may be determined that the bright spot 81 exists within the discharge determination frame only when the entire bright spot 81 is located within the discharge determination frame. In this case, in the adjustment of the temporary setting frame 850 by the focus shift frame size adjusting unit 78b described above, the amount of blur is added to each side of the temporary setting frame 850 and the temporary setting frame 850 is enlarged as the defocus amount increases. Is done. Thereby, the influence on the quality determination of the ejection operation due to the blurring of the bright spot 81 outside the focusing range 80 can be reduced, and the accuracy of the quality judgment of the ejection operation can be further improved. In the adjustment of the normal discharge determination frame 85 by the above-described light thickness adjustment unit 78c, the normal discharge determination frame 85 is expanded in the vertical direction as the determination frame irradiation distance error increases. As a result, the influence of the determination frame irradiation distance error on the quality determination of the ejection operation can be reduced, and the accuracy of the quality determination of the ejection operation can be improved.

  Further, the determination unit 75 obtains the center of gravity of each of the plurality of bright spots 81 on the inspection image 8, and the presence / absence of the center of gravity of the bright spot 81 in each normal discharge determination frame 85 is determined in each normal discharge determination frame 85. It may be acquired as the presence / absence information of the bright spot 81. Thereby, for example, when only the part of the bright spot 81 located outside the in-focus range 80 that is blurred and spread is located in the normal ejection determination frame 85, the bright spot 81 is present in the normal ejection determination frame 85. It is prevented from being determined. The same applies to the determination of the presence / absence of the bright spot 81 in other ejection determination frames. As a result, it is possible to further improve the pass / fail judgment accuracy of the discharge operation at the plurality of discharge ports 314a to 314d. The presence / absence determination of the bright spot 81 based on the presence / absence of the center of gravity may be performed together with the first adjustment method and the third adjustment method described above. However, when the above-described second adjustment method or fourth adjustment method is performed, the presence / absence determination of the bright spot 81 based on the presence / absence of the center of gravity is not performed.

  Various changes can be made in the substrate processing apparatus 1.

  In the discharge inspection unit 5 described above, the determination frame setting unit 74 sets the normal discharge determination frame 85, the oblique discharge determination frames 87 and 87a, the protective liquid film discharge determination frame 88, and the maximum discharge determination frame 89. All of these discharge determination frames need not be set. In the discharge inspection unit 5, only one type of discharge determination frame may be set by the determination frame setting unit 74, or two or three types of discharge determination frames may be set in combination.

  For example, the maximum discharge determination frame 89 corresponding to the area outside the protective liquid film 93 may be omitted. In this case, the in-protection-film discharge determination frame 88 is an outer discharge determination frame located on the outermost side among the plurality of discharge determination frames. Further, the discharge operation at each of the discharge ports 314a to 314d is performed by the determination unit 75 outside the region corresponding to the normal discharge, the oblique discharge to the region corresponding to the oblique discharge determination frames 87 and 87a, and the oblique discharge determination frames 87 and 87a. Therefore, it is determined as one of larger oblique discharge onto the protective liquid film 93 and other discharge failures. Other ejection failures are non-ejection or larger oblique ejection that deposits outside the protective liquid film 93.

  Of the discharge determination frames, the in-protection liquid film discharge determination frame 88 may be omitted. In this case, the maximum discharge determination frame 89 is set around the plurality of oblique discharge determination frames 87 or the plurality of oblique discharge determination frames 87a. The discharge operation at each of the discharge ports 314a to 314d is normal discharge, oblique discharge to the region corresponding to the oblique discharge determination frames 87 and 87a, and larger oblique discharge to the outside of the region corresponding to the oblique discharge determination frames 87 and 87a. And non-ejection.

  When the oblique discharge determination frames 87 and 87a are omitted from the discharge determination frames, the discharge operation at each of the discharge ports 314a to 314d is normal discharge, oblique discharge onto the protective liquid film 93, and liquid landing outside the protective liquid film 93. It is determined as one of larger oblique discharge and non-discharge. When the oblique discharge determination frames 87 and 87a and the protective liquid film discharge determination frame 88 are omitted, the discharge operation at each of the discharge ports 314a to 314d is determined as one of normal discharge, diagonal discharge, and non-discharge.

  In the above description, the non-ejection and the oblique ejection are determined as the ejection failure of the ejection port 314a, but other ejection operations may also be determined as the ejection failure. For example, the droplets ejected from the ejection head 31 may break up during flight and become a plurality of extremely small droplets. Such a very small droplet cannot give sufficient kinetic energy to the upper surface 91 of the substrate 9, and the substrate 9 may not be cleaned properly. Therefore, the discharge of such a small droplet may also be determined as a discharge failure of the discharge port. When determining the discharge of a very small droplet as a discharge failure, for example, a case where one bright spot 81 is detected in the normal discharge determination frame 85 is determined as normal discharge, and a plurality of bright dots are detected in the normal discharge determination frame 85. The case where the point 81 is detected is determined as a discharge failure.

  In the discharge inspection unit 5, the bright spot 81 is reduced in the vertical direction around the center of gravity so that the vertical and horizontal lengths of the bright spot 81 are approximately equal before the quality determination of the discharge operation is performed. Also good.

  In the light emission part 51, it is not always necessary to emit light in a planar shape. Light extending linearly forward from the light emission part 51 is emitted along the light existence surface, and the light is emitted along the light existence surface. You may scan by optical scanning means, such as a polygon mirror. Accordingly, when the plurality of flying bodies that are the processing liquids discharged from the plurality of discharge ports 314a to 314d pass through the light existence surface, the plurality of flying bodies are irradiated with light. The light existence surface may be perpendicular to the designed ejection direction of the processing liquid from the ejection head 31, and the imaging direction in the imaging unit 52 is parallel to a plane perpendicular to the designed ejection direction. May be.

  The light emitting unit 51 and the imaging unit 52 may be disposed at a position other than the diagonally lower side of the ejection head 31, for example, the diagonally upper side of the ejection head 31. The discharge inspection unit 5 may be disposed at a position other than the vicinity of the standby position of the discharge head 31 (that is, the vicinity of the standby pod 4). For example, the light emitting unit 51 and the imaging unit 52 may be disposed obliquely above the ejection head 31 located on the substrate 9.

  The treatment liquid ejected from the ejection head 31 is not necessarily limited to a droplet shape, and a treatment liquid continuous in a liquid column shape may be ejected from the ejection head 31.

  The substrate processing apparatus 1 may be used for various processes other than the cleaning of the substrate 9. Moreover, in the substrate processing apparatus 1, you may utilize for the process of the glass substrate used for display apparatuses other than a semiconductor substrate, such as a liquid crystal display device, a plasma display, and FED (field emission display). Alternatively, the substrate processing apparatus 1 may be used for processing of an optical disk substrate, a magnetic disk substrate, a magneto-optical disk substrate, a photomask substrate, a ceramic substrate, a solar cell substrate, and the like.

  The apparatus including the light emitting unit 51, the imaging unit 52, the determination frame setting unit 74, and the determination unit 75 described above may be used as a discharge inspection apparatus that is independent from other configurations of the substrate processing apparatus 1. For example, in the apparatus for discharging liquid from a plurality of discharge ports to the above-described various substrates, the discharge inspection apparatus is used for inspecting a liquid discharge operation from the plurality of discharge ports.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 5 Discharge inspection part 8 Inspection image 9 Substrate 21 Substrate holding part 31 Discharge head 51 Light emitting part 52 Imaging part 74 Judgment frame setting part 75 Judgment part 77 Temporary setting part 78 Frame size adjustment part 81 Bright spot 85 Normal discharge Determination frame 87, 87a Oblique discharge determination frame 88 Protection liquid film discharge determination frame 89 Maximum discharge determination frame 314a to 314d Discharge port 510 Planar light 850 Temporary setting frame J1 Optical axis

Claims (13)

A discharge inspection device for inspecting the discharge operation of liquid from a plurality of discharge ports,
By emitting light along a predetermined light existence plane, when the plurality of flying bodies, which are liquids ejected from the plurality of ejection openings, pass through the light existence plane, light is emitted to the plurality of flying bodies. A light emitting portion to irradiate;
An imaging unit for acquiring an inspection image including a plurality of bright spots appearing on the plurality of flying objects by imaging the plurality of flying objects passing through the light existence surface;
A determination frame setting unit for setting a plurality of normal discharge determination frames corresponding to the plurality of discharge ports on the inspection image;
A determination unit for acquiring presence / absence information of a bright spot in each normal discharge determination frame, and determining the quality of the discharge operation at the discharge port corresponding to each normal discharge determination frame based on the presence / absence information;
With
The determination frame setting unit
A normal discharge determination frame of a predetermined size is centered on a bright spot reference position, which is a point where a discharge center line extending from each discharge port in the design discharge direction of the plurality of flying bodies intersects the light existence surface. A temporary setting unit that temporarily sets the inspection image corresponding to each discharge port;
A frame size adjustment unit that adjusts each normal ejection determination frame temporarily set by the temporary setting unit based on an inspection distance that is a distance between the bright spot reference position and the imaging unit;
A discharge inspection apparatus comprising: The discharge inspection apparatus according to claim 1,
The discharge inspection apparatus, wherein the frame size adjustment unit performs adjustment to reduce the size of each normal discharge determination frame as the inspection distance increases. The discharge inspection apparatus according to claim 1 or 2,
The discharge inspection apparatus, wherein the frame size adjustment unit performs adjustment to reduce the size of each normal discharge determination frame as the difference between the focus distance of the imaging unit and the inspection distance increases. The discharge inspection apparatus according to any one of claims 1 to 3,
The distance between the light emitting part and the bright spot reference position in a direction parallel to the optical axis between the light emitting part and the bright spot reference position is an irradiation distance.
The frame size adjustment unit has a difference between the irradiation distance and the distance between the light thinnest position where the thickness of the light emitted from the light emitting unit is the smallest in the ejection direction and the light emitting unit. A discharge inspection apparatus further comprising a light thickness adjustment unit that reduces each normal discharge determination frame in the discharge direction as the size increases. The discharge inspection apparatus according to any one of claims 1 to 4,
An ejection inspection apparatus, wherein an imaging direction of the imaging unit is inclined with respect to a plane perpendicular to the ejection direction. A discharge inspection apparatus according to any one of claims 1 to 5,
The discharge inspection apparatus, wherein the light existence surface is inclined with respect to a plane perpendicular to the discharge direction. The discharge inspection apparatus according to any one of claims 1 to 6,
The plurality of discharge ports are arranged in a straight line,
The discharge inspection apparatus, wherein the determination frame setting unit sets the positions of the plurality of normal discharge determination frames based on the positions of bright spots located at both ends of the plurality of bright spots included in the inspection image. . A discharge inspection apparatus according to any one of claims 1 to 7,
The determination frame setting unit sets a plurality of oblique discharge determination frames around the plurality of normal discharge determination frames,
The discharge inspection apparatus, wherein the determination unit determines whether or not an oblique discharge has occurred at a discharge port corresponding to each oblique discharge determination frame based on the presence or absence of a bright spot in each oblique discharge determination frame. The discharge inspection apparatus according to claim 8,
The determination frame setting unit sets one outer discharge determination frame around the plurality of oblique discharge determination frames;
The discharge inspection apparatus, wherein the determination unit determines whether or not a larger oblique discharge has occurred based on presence / absence information of a bright spot in the outer discharge determination frame. A discharge inspection apparatus according to any one of claims 1 to 7,
The determination frame setting unit sets one oblique discharge determination frame around the plurality of normal discharge determination frames;
The discharge inspection apparatus, wherein the determination unit determines whether or not an oblique discharge has occurred based on the presence or absence of a bright spot in the oblique discharge determination frame. The discharge inspection apparatus according to claim 10,
The determination frame setting unit sets one outer discharge determination frame around the oblique discharge determination frame;
The discharge inspection apparatus, wherein the determination unit determines whether or not a larger oblique discharge has occurred based on presence / absence information of a bright spot in the outer discharge determination frame. The discharge inspection apparatus according to any one of claims 1 to 11,
The determination unit obtains the center of gravity of each of the plurality of bright spots on the inspection image, and determines whether or not the center of gravity of the bright spot in each normal ejection determination frame is present. A discharge inspection apparatus characterized by being acquired as presence / absence information. A substrate processing apparatus,
A substrate holder for holding the substrate;
A discharge head for discharging a liquid from a plurality of discharge ports toward the substrate and performing a predetermined process on the substrate;
The discharge inspection apparatus according to any one of claims 1 to 12, wherein the discharge operation of the liquid from the plurality of discharge ports of the discharge head is inspected.
A substrate processing apparatus comprising:

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