JP6126505B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a substrate processing 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 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. The CCD camera used for imaging is fixed to the nozzle head unit together with the coating solution nozzle. Based on the imaging result, the occurrence of dripping or dripping from the tip of the coating liquid nozzle is detected.

  Patent Document 3 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 4 discloses a substrate processing apparatus that discharges micro 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 2008-135679 A JP 2012-98812 A JP 2012-209513 A

  By the way, in the structure in which the camera is fixed to the nozzle head portion as in Patent Document 2, the nozzle head portion is increased in size. For this reason, if it is not necessary to observe the state of the moving coating liquid nozzle, the camera is preferably provided in the vicinity of the standby position independently of the nozzle head portion.

  In the substrate processing apparatus, even when the ejection head moves to the standby position, even if it stops at a position slightly deviated from the designed standby position, there is no substantial effect on the processing on the substrate. However, if an imaging unit fixed in the vicinity of the standby position is used to image the processing liquid from the ejection head and inspect the quality of the ejection operation, the inspection accuracy may decrease due to the displacement of the ejection head. In particular, as disclosed in Patent Document 4, in an apparatus that ejects micro droplets from a plurality of ejection ports, the interval between micro droplets and the size of each micro droplet vary depending on the distance from the imaging unit. There is a possibility that the inspection accuracy is greatly lowered due to the positional deviation.

  The present invention has been made in view of the above problems, and it is an object of the present invention to correct displacement of the ejection head and improve inspection accuracy.

  The invention according to claim 1 is a substrate processing apparatus, comprising: a substrate holding unit that holds a substrate; and a plurality of discharge ports that discharge liquid toward the substrate above the substrate to discharge the liquid onto the substrate. An ejection head that performs processing; a head moving mechanism that moves the ejection head from above the substrate to an inspection region; and an ejection inspection apparatus that inspects the ejection operation of liquid from the plurality of ejection ports of the ejection head. The discharge inspection device emits light along a predetermined light existence surface, whereby a plurality of flying liquids that are liquids discharged from the plurality of discharge ports of the discharge head located in the inspection region When the body passes through the light existence plane, the plurality of flying bodies are imaged by imaging a light emitting unit that irradiates light to the plurality of flying bodies and the plurality of flying bodies that pass through the light existence plane. Multiple appearing above An imaging unit that acquires an inspection image including a point, and light from the light emitting unit in a state in which liquid is normally ejected from the plurality of ejection ports of the ejection head located at a predetermined design inspection position in the inspection area A reference image storage unit that stores a reference image that is an image acquired by the imaging unit while emitting, a position of the ejection head when the inspection image is acquired based on the reference image and the inspection image, and the A determination unit that corrects a relative shift of the inspection image with respect to the reference image due to a difference from a design inspection position, and determines whether or not the discharge operation is good at the plurality of discharge ports.

  A second aspect of the present invention is the substrate processing apparatus according to the first aspect, wherein the discharge head is moved to the design inspection position based on the reference image and the inspection image, and then the plurality of discharges are performed. The relative deviation correction is performed by the determination unit by re-acquiring an inspection image including a plurality of bright spots appearing on a plurality of flying objects passing through the light existence surface by discharging liquid from the outlet. The determination unit determines the quality of the discharge operation at the plurality of discharge ports based on the re-acquired inspection image.

  A third aspect of the present invention is the substrate processing apparatus according to the first or second aspect, wherein the plurality of discharge ports are a collection of discharge ports arranged linearly in the discharge port array direction. The plurality of discharge port arrays are arranged in a direction inclined with respect to the discharge port array direction.

  A fourth aspect of the present invention is the substrate processing apparatus according to any one of the first to third aspects, wherein the discharge head is rotated about a predetermined rotation axis by the head moving mechanism. It moves between above the substrate and the inspection area.

  A fifth aspect of the present invention is the substrate processing apparatus according to any one of the first to fourth aspects, wherein an imaging direction in the imaging unit is a plane perpendicular to a predetermined ejection direction of the plurality of flying objects. It is inclined with respect to it.

  A sixth aspect of the present invention is the substrate processing apparatus according to any one of the first to fifth aspects, wherein the light-existing surface is perpendicular to a plane perpendicular to a predetermined ejection direction of the plurality of flying objects. Inclined.

  A seventh aspect of the present invention is the substrate processing apparatus according to any one of the first to sixth aspects, wherein the discharge inspection apparatus has a plurality of normal discharges corresponding to the plurality of discharge ports on the inspection image. A determination frame setting unit for setting a determination frame is further provided, and after the correction of the shift of the inspection image, the determination unit acquires bright spot presence / absence information in each normal ejection determination frame, and based on the presence / absence information Then, the quality of the discharge operation at the discharge port corresponding to each normal discharge determination frame is determined.

  The invention according to claim 8 is the substrate processing apparatus according to any one of claims 1 to 6, wherein the determination unit corrects the deviation of the inspection image, and then the reference image and the inspection image. The quality of the discharge operation at each of the plurality of discharge ports is determined based on the difference between the two.

  In the present invention, it is possible to correct the displacement of the ejection head and improve the inspection accuracy.

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 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 side view of a discharge head and a standby pod. 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 the corrected test | inspection image. It is a figure which shows the corrected test | inspection image. It is a figure which shows the corrected test | inspection image. It is a figure which shows the corrected test | inspection image. It is a figure which shows the corrected test | inspection image. It is a figure which shows a difference image.

  FIG. 1 is a front view of a substrate processing apparatus 1 according to an embodiment of the present invention. FIG. 2 is a plan view of the substrate processing apparatus 1. In FIG. 2, 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.

  As shown in FIGS. 1 and 2, 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 head moving mechanism 35, and a protective liquid supply unit. 36, a standby pod 4, a discharge inspection unit 5, a chamber 6, and a control unit. The chamber 6 includes a substrate holding unit 21, a cup unit 22, a substrate rotating mechanism 23, a processing liquid supply unit 3, a head moving mechanism 35, a protective liquid supply unit 36, a standby pod 4, and a discharge inspection unit 5. To house. The chamber 6 is a light shielding chamber that blocks light from entering the internal space 60 from the outside. 1 and 2, 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. In FIG. 2, illustration of the processing liquid piping 32 is omitted. 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. A plurality of discharge ports including four discharge port arrays 313 a to 313 d are provided on the lower surface 311 of the discharge head 31. Each of the discharge port arrays 313a to 313d is a set of a plurality of discharge ports 314a to 314d arranged substantially 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 left-right direction in FIG. 3 which is the discharge port arrangement direction of each of the discharge port arrays 313a to 313d is referred to as “array direction”. Each of the discharge port arrays 313a to 313d has a linear shape extending in the arrangement direction. The ejection port arrays 313a to 313d are arranged in parallel to each other in a direction perpendicular to the arrangement direction (that is, the vertical direction in FIG. 3). Note that the ejection port arrays 313a to 313d do not necessarily need to be arranged perpendicular to the arrangement direction, but may be arranged in a direction inclined with respect to the arrangement direction.

  In the following description, 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”. They are referred to as “outlet row 313c” and “fourth discharge port 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”.

  In the direction perpendicular to the arrangement direction, the distance between the first outlet row 313a and the second outlet row 313b is equal to the distance between the third outlet row 313c and the fourth outlet row 313d. The distance is smaller than the distance between the second discharge port array 313b and the third discharge port array 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.

  As shown in FIGS. 1 and 2, the head moving mechanism 35 includes an arm 351, a rotating shaft 352, a head rotating mechanism 353, and a head lifting 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 rotating mechanism 353 rotates and moves 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 a ball screw mechanism and an electric motor, and can accurately position the ejection head 31. The head lifting mechanism 354 may include an air cylinder.

  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 substrate 9 is processed by controlling the substrate rotation mechanism 23, the processing liquid supply unit 3, the head moving mechanism 35, the protective liquid supply unit 36, and the like by the processing control unit 71. By controlling the processing liquid supply unit 3, the head moving mechanism 35, the discharge inspection unit 5, and the like by the inspection control unit 72, the processing liquid from the plurality of discharge ports 314 a to 314 d (see FIG. 3) of the discharge head 31. The ejection operation is inspected.

  The inspection calculation unit 73 is a part of the ejection inspection unit 5 and includes a reference image storage unit 731, a determination frame setting unit 74, and a determination unit 75. The reference image storage unit 731 stores a reference image 732 described later in advance. The determination unit 75 includes a misalignment correction unit 751 and a pass / fail determination unit 752. The reference image storage unit 731, the determination frame setting unit 74, and the determination unit 75 are used for the above-described ejection operation inspection.

  When processing the substrate 9 in the substrate processing apparatus 1 shown in FIGS. 1 and 2, first, the substrate 9 is carried into the chamber 6 and is held by the substrate holding unit 21. When the substrate 9 is carried in, the ejection head 31 stands by at a standby position on the standby pod 4 provided outside the cup portion 22 as indicated by a two-dot chain line in FIG. FIG. 5 is an enlarged side view showing the ejection head 31 located at the standby position 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. In FIG. 5, the protective liquid supply unit 36 is not shown. In addition, an ejection head 31 located in an inspection area to be described later is indicated by a two-dot chain line. As shown in FIGS. 1 and 2, when the substrate 9 is held by the substrate holding unit 21, the substrate rotation mechanism 23 is driven by the processing control unit 71 (see FIG. 4), and the rotation of the substrate 9 is started.

  Subsequently, the head rotation mechanism 353 and the head lifting 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 and moved downward above the cup unit 22. To do. 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 discharge of the processing liquid from the plurality of discharge ports 314a to 314d (see FIG. 3) of the discharge head 31 toward the upper surface 91 of the substrate 9 on which the protective liquid film is formed (that is, the injection of microdroplets) is started. Is done. 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 protective liquid supply unit 36 are rotated by the head rotation mechanism 353 in parallel with the discharge of the protective 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 moved to the edge of the substrate 9 together with the removed foreign matter by the rotation of the substrate 9 and scattered from the edge of the substrate 9 to the outside. 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 ejection 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 are moved from above the substrate 9 to the inspection region above the standby pod 4 by the head rotation mechanism 353. And rotate.

  The inspection area is an area above the standby position described above. The inspection area is a small area having a predetermined design inspection position (hereinafter referred to as “design inspection position”) as a substantial center. In other words, the inspection area includes a design inspection position and a position in the vicinity of the design inspection position. When the discharge head 31 rotates from above the substrate 9 to above the standby pod 4, the discharge head 31 stops at any position in the inspection region. In the inspection area, the discharge inspection unit 5 periodically or as necessary inspects the discharge operation of the processing liquid from the plurality of discharge ports 314a to 314d of the discharge head 31.

  FIG. 6 is a perspective view showing the ejection head 31 in the inspection region and the ejection inspection unit 5 disposed 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. 6 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. 6, the optical axis J <b> 1 of the light emitting portion 51 is drawn with a one-dot chain line, and the outline of the planar light emitted from the light emitting portion 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, 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 located in the inspection region pass through the above-described light existence surface (that is, pass through the planar light 510). ), The light emitting unit 51 emits light 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. 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.

  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 inspection image is sent to the inspection calculation unit 73 (see FIG. 4) of the control unit 7. In the inspection calculation unit 73, binarization processing is performed on the inspection image to extract a plurality of bright spots and remove background noise and the like.

  FIG. 7 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. 7, 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. 8 and 11 to 15.

  Subsequently, the inspection image 8 and the reference image 732 stored in advance in the reference image storage unit 731 are compared by the positional deviation correction unit 751 of the determination unit 75. In the substrate processing apparatus 1, the reference image 732 is generated when the ejection head 31 is positioned at the design inspection position in the inspection area and the processing liquid is normally ejected from the plurality of ejection ports 314 a to 314 d. It is an image acquired by the imaging unit 52 while emitting the planar light 510 from the emission unit 51. The reference image 732 is acquired before the substrate 9 is processed in the substrate processing apparatus 1 (for example, before the substrate processing apparatus 1 is shipped at the manufacturing site of the substrate processing apparatus 1), and is similar to the inspection image 8. After the binarization process is performed, it is stored in advance in the reference image storage unit 731.

  Based on the inspection image 8 and the reference image 732, the positional deviation correction unit 751 obtains a relative deviation (hereinafter referred to as “image deviation”) of the inspection image 8 with respect to the reference image 732. The image shift is caused by a difference between the position of the ejection head 31 when the inspection image 8 is acquired and the design inspection position. The amount of image shift is calculated, for example, until the difference between the inspection image 8 and the reference image 732 is minimized (that is, the overlap between the plurality of bright spots 81 of the inspection image 8 and the plurality of bright spots of the reference image 732). The inspection image 8 is moved in the vertical and horizontal directions in FIG. 7, rotated around a rotation axis perpendicular to the inspection image 8, and the inspection image 8 is enlarged or reduced. Is done. The amount of movement, rotation, and magnification of the inspection image 8 when the difference between the inspection image 8 and the reference image 732 is minimized is the image shift amount of the inspection image 8. The image shift amount may be obtained by applying a general image processing function for pattern matching to the inspection image 8 and the reference image 732.

  The position deviation correction unit 751 corrects the image deviation of the inspection image 8 based on the obtained image deviation amount. Specifically, the position of the plurality of bright spots 81 on the inspection image 8 is corrected to a position when it is assumed that the inspection image 8 is acquired in a state where the ejection head 31 is positioned at the design inspection position in the inspection region. Is done. Thus, an inspection image in which the image shift amount is corrected (hereinafter referred to as “bright spot position corrected inspection image”) is generated.

  Instead of generating the bright spot position corrected inspection image by correcting the image shift, the inspection image 8 with the corrected image shift may be acquired by re-imaging the bright spot 81. Specifically, first, the processing control unit 71 controls the head rotation mechanism 353 and the head lifting mechanism 354 of the head moving mechanism 35 based on the image shift amount obtained by the position shift correction unit 751. Thereby, the ejection head 31 is moved (that is, fine adjustment of the position of the ejection head 31 is performed), and the ejection head 31 is positioned at the design inspection position. Then, micro droplets of the processing liquid are ejected from the plurality of ejection ports 314 a to 314 d of the ejection head 31. Then, a plurality of bright spots 81 generated when a plurality of minute droplets pass through the planar light 510 are imaged by the imaging unit 52, whereby an inspection image in which the image shift is corrected (hereinafter referred to as “re-acquisition”). "Inspection image"). Since the reacquired inspection image is acquired in a state where the ejection head 31, the light emitting unit 51, and the imaging unit 52 are positioned in the positional relationship assumed in the design, the re-acquired inspection image is also arranged in the position assumed in the design. The positional deviation from the normal ejection determination frame 85 (described later) can be made extremely small. In the following description, the bright spot position corrected inspection image generated by the image misalignment correction unit 751 and the reacquired inspection image acquired by re-imaging are collectively referred to as a corrected inspection image 8c.

  Next, as shown in FIG. 8, the plurality of normal discharge determination frames 85 respectively corresponding to the plurality of discharge ports 314a to 314d are obtained after the image shift is corrected by the determination frame setting unit 74 (see FIG. 4). It is set on the corrected inspection image 8c. 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 corrected inspection image 8c 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 corrected inspection image 8c. 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 position of each normal discharge determination frame 85 (that is, the coordinates on the corrected inspection image 8c) 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 such that the discharge center line extending from each discharge port of the discharge head 31 located at the design inspection position in the design discharge direction of the processing liquid is the planar light 510 (that is, the above-described light existence surface). It is a crossing point. Each normal ejection determination frame 85 is set around the bright spot reference position on the corrected inspection image 8c. Therefore, if a plurality of normal ejection determination frames 85 are set on the reference image 732, each bright spot of the reference image 732 is located at the approximate center of the corresponding normal ejection determination frame 85.

  The bright spot reference position on the corrected inspection image 8c can be obtained by various methods. For example, the direction of the ejection head 31 at the design inspection position, the positions of the ejection ports 314a to 314d in the ejection head 31, the ejection direction of the designed processing liquid, the position of the planar light 510, and the position and orientation 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 corrected inspection image 8c are obtained by performing perspective projection conversion of 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 corrected inspection image 8c are acquired.

  The plurality of normal ejection determination frames 85 are arranged in a direction corresponding to the arrangement direction described above on the corrected inspection image 8c. 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”.

  On the corrected inspection image 8c, the distance between adjacent bright spot reference positions in the arrangement direction 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). For this reason, the interval between the plurality of normal ejection determination frames 85 included in the first normal ejection determination frame row 86a is similarly reduced as the distance from the imaging unit 52 increases. The same applies to 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.

  As shown in FIG. 8, the plurality of normal ejection determination frames 85 are arranged on the corrected inspection image 8c without overlapping each other. If the normal ejection determination frames 85 overlap on the corrected inspection image 8c, the position and orientation of the imaging unit 52 and the planar shape from the light emitting unit 51 until the plurality of normal ejection determination frames 85 do not overlap each other. The position and direction of the light 510 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 be a plurality of oblique on the corrected inspection image 8c. It is set around the discharge determination 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. 9, 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, the corresponding intersections 95 are obtained on the planar light 510, and these intersections 95 are projected onto the corrected inspection image 8c and connected in order, thereby protecting as shown in FIG. An in-liquid film discharge determination frame 88 is set.

  When the setting of the protective liquid film discharge determination frame 88 is completed, the determination frame setting unit 74 sets one maximum discharge determination frame 89 surrounding the protective liquid film discharge determination frame 88 on the corrected inspection image 8c. 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 pass / fail determination unit 752 of the determination unit 75 Existence information of the bright spot 81 in each discharge determination frame, that is, information indicating whether or not the bright spot 81 exists in each discharge determination frame is acquired. In the quality determination unit 752, if at least a part of the bright spot 81 is located within the discharge determination frame, it is determined that the bright spot 81 is present within the discharge determination frame. Further, when the bright spot 81 is located across the two inner and outer ejection determination frames, it is determined that the bright spot 81 does not exist in the outer ejection determination frame but exists in the inner ejection determination frame. Is done. 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 pass / fail determination unit 752, 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 a noticeable bright spot on the corrected inspection image 8c. 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 pass / fail determination unit 752 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 determining whether or not the bright spot 81 is present, the quality determination unit 752 excludes the area outside the maximum ejection determination frame 89 in the corrected inspection image 8c 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. Thereby, the time required for the bright spot detection by the pass / fail judgment unit 752 is shortened, and the time required for the pass / fail judgment 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 quality determination unit 752 determines the quality of the ejection operation at the ejection ports 314a to 314d corresponding to each normal ejection determination frame 85. For a specific example of the quality determination of the discharge operation, see FIG. A to FIG. This will be described below with reference to E.

  FIG. A to FIG. E is a diagram conceptually showing a part of the corrected inspection image 8c. FIG. A to 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. 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 pass / fail judgment unit 752 obtains 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 pass / fail determination unit 752 as the presence / absence information of the bright spot 81. 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 pass / fail determination unit 752 as the presence / absence information of the bright spot 81.

  Based on the presence / absence information, the pass / fail determination unit 752 determines that the discharge operations at the four first discharge ports 314a respectively 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 quality determination unit 752 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 protective liquid film ejection determination frame 88 are acquired by the pass / fail judgment unit 752 as the presence / absence information of the bright spot 81. Based on the presence / absence information, the pass / fail determination unit 752 determines that the discharge operations at the four first discharge ports 314a respectively 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 quality determination unit 752 to the operator or the like through the notification unit 79, and maintenance of the ejection head 31 is performed.

  In the pass / fail determination unit 752, 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 pass / fail judgment unit 752 obtains the presence / absence information of the bright spot 81. Based on the presence / absence information, the pass / fail determination unit 752 determines that the discharge operations at the four first discharge ports 314a respectively 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 the ejection failure is notified from the quality determination unit 752 to the operator or the like through a notification unit 79 such as a monitor of the ejection 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. To be replaced.

  In the pass / fail determination unit 752, the discharge port corresponding to the bright spot 81 in the maximum discharge determination frame 89 may not be specified. 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 within the protective liquid film discharge determination frame 88 and the maximum discharge determination frame 89 are provided by the pass / fail determination unit 752 as presence / absence information of the bright spot 81. To be acquired. Based on the presence / absence information, the pass / fail determination unit 752 determines that the discharge operations at the four first discharge ports 314a respectively 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 314a to 314d on the corrected inspection image 8c. The 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). As a result, it is possible to suppress or prevent an adverse effect on processing on the substrate 9 due to ejection failure. As the adverse effect, for example, the quality of the processing on the substrate 9 is deteriorated due to non-ejection of the processing liquid, and the pattern on the substrate 9 is damaged due to the oblique ejection of the processing liquid.

  Further, in the substrate processing apparatus 1, the difference between the position of the ejection head 31 and the design inspection position when the inspection image 8 is acquired based on the reference image 732 and the inspection image 8 by the position deviation correction unit 751 of the determination unit 75. After the image misalignment due to is corrected, the quality determination unit 752 obtains the above-described presence / absence information and determines the quality of the ejection operation. Thereby, the positional deviation from the design inspection position of the discharge head 31 in the inspection region can be corrected, and the inspection accuracy of the discharge operation at the plurality of discharge ports 314a to 314d can be improved.

  As described above, the ejection head 31 is rotationally moved between the upper portion of the substrate 9 and the inspection region by the head rotation mechanism 353. For this reason, the position of the bright spot 81 on the inspection image 8 is largely and complicatedly shifted due to a slight shift of the rotation amount by the head rotating mechanism 353. Since the substrate processing apparatus 1 can correct the displacement of the ejection head 31 and accurately inspect the ejection operation as described above, the structure of the substrate processing apparatus 1 is a substrate process in which the ejection head rotates. Particularly suitable for the structure of the device.

  As shown in FIG. 3, the ejection head 31 is provided with a number of ejection ports 314 a to 314 d. For this reason, there are many bright spots in each of the reference image 732 and the inspection image 8. Therefore, even when there is a non-ejection ejection port in the ejection head 31 at the time of inspection and the number of bright spots 81 on the inspection image 8 is smaller than the number of bright spots on the reference image 732, the inspection image 8 By comparing the positions of the remaining many bright spots 81 with the positions of bright spots on the reference image 732, the image shift amount of the inspection image 8 can be obtained with high accuracy.

  As described above, the plurality of ejection ports 314a to 314d of the ejection head 31 include the ejection port arrays 313a to 313d that extend substantially linearly in the arrangement direction and are arranged in a direction inclined with respect to the arrangement direction. For this reason, even when the ejection ports at the end of one ejection port array are non-ejection, the distance corresponding to the arrangement pitch of the inspection image 8 on the non-ejection ejection port side when detecting image misalignment Thus, it is prevented that the difference between the inspection image 8 and the reference image 732 is determined to be the smallest at a position shifted from the reference image 732 only. Thereby, the image shift amount of the inspection image 8 can be acquired with higher accuracy.

  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 314a to 314d on the corrected inspection image 8c. 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.

  In the discharge inspection unit 5, the determination frame setting unit 74 sets the discharge determination frame 88 in the protective liquid film corresponding to the protective liquid film 93 on the corrected inspection image 8c. 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.

  Further, in the discharge inspection unit 5, the determination frame setting unit 74 sets a maximum discharge determination frame 89 surrounding the protective liquid film discharge determination frame 88 on the corrected inspection image 8c. 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 corrected inspection image 8c. Further, it is possible to suppress the plurality of normal ejection determination frames 85 from overlapping each other on the corrected inspection image 8c 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 prevent 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 corrected inspection image 8c. 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 example, the normal ejection determination frame 85 is set on the corrected inspection image 8c after the image shift is corrected, but the normal ejection determination frame 85 is set on the inspection image 8 where the image shift is not corrected. The position of the normal ejection determination frame 85 may be corrected by the position shift correction unit 751 based on the image shift. Even in this case, after correcting the image shift based on the reference image 732 and the inspection image 8, each normality is determined by the quality determination unit 752 based on the presence / absence information of the bright spot 81 in each normal ejection determination frame 85. The quality of the discharge operation at the discharge ports 314a to 314d corresponding to the discharge determination frame 85 is accurately determined.

  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. A relatively large oblique ejection determination frame 87a with the determination frame 85 positioned inside may be set on the corrected inspection image 8c. In the example shown in FIG. 11, 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 ejection determination frame 87a on the corrected inspection image 8c is set based on the position of the corresponding normal ejection 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 quality determination unit 752 determines the quality of the ejection operation at the ejection ports 314a to 314d corresponding to each normal ejection determination frame 85.

  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 corrected inspection image 8c, 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. There is a possibility that it is easier to determine that the pixel exists within the ejection determination frame than the bright spot 81 close to the portion 52.

  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 may be more likely to be determined to exist within 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 corrected inspection image 8c, and widen compared with the bright spots 81 in the focusing range 80. Since there is a high possibility that a part of the spread bright spot 81 is located in the discharge determination frame, another bright spot 81 is determined in the presence / absence determination of the bright spot 81 in the discharge determination frame such as the normal discharge determination frame 85. There is a possibility that it is easier to determine that it is within the discharge determination frame than.

  Therefore, in the discharge inspection unit 5, the adjustment for reducing 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 blurring of the bright spot 81 outside the focusing range 80, It is done as needed. 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 corrected inspection image 8c is adjusted before the determination unit 75 determines whether the ejection operation is good or bad.

  In the first adjustment method, first, an inspection distance that is the distance between the bright spot reference position corresponding to each normal ejection determination frame 85 shown in FIG. 8 and the start point of the imaging axis J2 of the imaging unit 52 is obtained. Subsequently, the size of the normal ejection determination frame 85 is adjusted so that the normal ejection determination frame 85 becomes smaller as the inspection distance increases. Specifically, a predetermined function of the inspection distance that becomes smaller as the inspection distance of each normal discharge determination frame 85 becomes the frame reduction ratio, and the center position (that is, the bright spot reference position) of each normal discharge determination frame 85 is determined. The size of each normal discharge determination frame 85 is adjusted as shown in FIG. 12 by multiplying the lengths of the four sides of each normal discharge determination frame 85 by the frame reduction rate without changing. . In FIG. 12, the illustration of the discharge determination frames other than the normal discharge determination frame 85 is omitted (the same applies to FIGS. 13 to 15).

  Next, the size of each normal ejection determination frame 85 increases the difference between the in-focus distance of the imaging unit 52 and the inspection distance corresponding to each normal ejection determination frame 85 (hereinafter, referred to as “focus shift amount”). It is further adjusted so as to become smaller. Specifically, a predetermined function of the defocus amount that increases as the defocus amount increases is used as the blur amount, and the four positions of each normal discharge determination frame 85 are changed without changing the center position of each normal discharge determination frame 85. By subtracting the amount of blur from the length of each side, each normal ejection determination frame 85 is set as shown in FIG.

  Based on the presence / absence information of the bright spot 81 in the normal discharge determination frame 85 whose size is adjusted, the quality of the discharge operation at each of the discharge ports 314a to 314d is determined. In the adjustment of the normal discharge determination frame 85, as described above, the adjustment for reducing each normal discharge determination frame 85 is performed as the inspection distance corresponding to each normal discharge determination frame 85 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 defocus amount, which is the difference between the inspection distance corresponding to each normal ejection determination frame 85 and the focusing distance of the imaging unit 52, increases, adjustment is performed to reduce each normal ejection determination frame 85. 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 adjustment based on the inspection distance and the adjustment based on the defocus amount are performed for each normal ejection determination frame 85. However, it is not always necessary to perform both adjustments. Only one of the adjustments may be performed.

  In the second adjustment method described above, the size of the bright spot 81 is corrected so that each bright spot 81 becomes smaller as the inspection distance corresponding to each bright spot 81 becomes smaller. 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. Subsequently, the size of the bright spot 81 is corrected so that each bright spot 81 becomes smaller as the defocus amount 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.

  Then, based on the presence / absence information of the bright spot 81 whose size is corrected in the normal discharge determination frame 85 (that is, information indicating whether or not at least a part of the corrected bright spot 81 exists), each discharge point is determined. The quality of the discharge operation at the outlets 314a to 314d is determined. In the correction of the bright spot 81, as described above, correction is performed to reduce each bright spot 81 as the inspection distance corresponding to each bright spot 81 becomes smaller. 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 correction based on the inspection distance and the correction based on the defocus amount are performed for each bright spot 81. However, it is not always necessary to perform both corrections. Only one of the corrections may be performed.

  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 corrected inspection image 8c is corrected before the quality determination of the ejection operation by the determination unit 75.

  In the third adjustment method, 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 bright spot reference position corresponding to each normal ejection determination frame 85 (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 optical thinnest position (hereinafter referred to as “the optical thinnest distance”). Based on a certain determination frame irradiation distance error, 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. 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 irradiation distance of each bright spot 81 (that is, the direction parallel to the optical axis J1 between the start point of the optical axis J1 of the light emitting portion 51 and the bright spot reference position corresponding to each bright spot 81). The vertical height of each luminescent spot 81 is adjusted based on the luminescent spot irradiation distance error, which is the difference between the distance between the luminescent spot 81 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 corrected 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, in the presence / absence determination of the bright spot 81 in the discharge determination frame such as the normal discharge determination frame 85 by the pass / fail determination unit 752, if at least a part of the bright spot 81 is located in the discharge determination frame, the bright spot 81 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 spots 81 are 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 normal ejection determination frame 85 by the above-described first adjustment method, the blur amount is added to each side of the normal ejection determination frame 85 and the normal ejection determination frame 85 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 third adjustment method described above, the normal discharge determination frame 85 is enlarged 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.

  In addition, the pass / fail judgment unit 752 obtains the center of gravity of each of the plurality of bright spots 81 on the corrected inspection image 8c, and the presence / absence of the center of gravity of the bright spot 81 in each normal ejection judgment frame 85 is determined based on each normal ejection judgment frame. 85 may be acquired as the presence / absence information of the bright spot 81 in 85. 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, the second adjustment method and the fourth adjustment method described above are not performed together with the presence / absence determination of the bright spot 81 based on the presence / absence of the center of gravity.

  The inspection operation unit 73 of the substrate processing apparatus 1 may inspect the discharge operation without using the discharge determination frame such as the normal discharge determination frame 85. In this case, the determination frame setting unit 74 is omitted from the inspection calculation unit 73. When an inspection that does not use the ejection determination frame is performed, first, similarly to the above, after the inspection image 8 is acquired and the binarization process is performed on the inspection image 8, the position shift of the determination unit 75 is performed. The correction unit 751 compares the inspection image 8 and the reference image 732 to obtain the above-described image shift. In the misalignment correcting unit 751, the image misalignment of the inspection image 8 is corrected as described above based on the obtained image misalignment amount, and a corrected inspection image 8c is generated.

  Subsequently, the quality determination unit 752 of the determination unit 75 generates a difference image 82 between the reference image 732 and the corrected inspection image 8c as shown in FIG. Specifically, first, the pixel value of the corresponding pixel in the corrected inspection image 8 c is subtracted from the pixel value of each pixel of the reference image 732. In the reference image 732 and the corrected inspection image 8c, the pixel value of the pixel included in each bright spot is positive, and the pixel value of the pixel included in the background is zero. Therefore, at a position where the bright spot of the reference image 732 and the bright spot 81 of the corrected inspection image 8c overlap, the difference value that is a value obtained by subtracting the pixel value of the inspection image 8 from the pixel value of the reference image 732 is zero. Also, the difference value is zero at the position where the background of the reference image 732 and the background of the corrected inspection image 8c overlap. On the other hand, the difference value is positive at a position where the bright spot 81 of the reference image 732 exists but the bright spot 81 of the corrected inspection image 8c does not exist. At the position where the bright spot 81 of the inspection image 8 exists but the bright spot of the reference image 732 does not exist, the difference value is negative.

  In the pass / fail judgment unit 752, the gradation value of a pixel having a negative difference value is set to the darkest zero, the gradation value of a pixel having a zero difference value is set to 127 of intermediate brightness, and the gradation value of a pixel having a positive difference value is set. The difference image 82 is generated with the value 255 being the brightest. In FIG. 16, only the outline of the first region 821 that is a set of pixels having a gradation value of 255 is shown. The second region 822, which is a set of pixels having a gradation value of 127, is indicated by parallel diagonal lines. A third region 823, which is a set of pixels having a gradation value of zero, is shown in a solid color.

  Next, the quality determination unit 752 extracts the first region 821 and the third region 823 from the difference image 82. In FIG. 16, one first area 821 and one third area 823 adjacent to the first area 821 exist in the left area of the difference image 82. Further, one first area 821 exists in the area on the right side of the reference image 732.

  One first region 821 on the left side corresponds to one bright spot on the reference image 732, and indicates that the bright spot 81 does not exist at a position corresponding to the bright spot on the corrected inspection image 8c. Further, one third region 823 adjacent to the first region 821 corresponds to one bright spot 81 on the inspection image 8, and a bright spot at a position corresponding to the bright spot 81 on the reference image 732. Indicates that does not exist. Therefore, in the pass / fail judgment unit 752, the processing liquid is not discharged in the designed discharge direction at the discharge port corresponding to the first region 821, and the processing liquid is discharged in the direction toward the third region 823. Determined.

  In the pass / fail determination unit 752, a distance between the first region 821 and the third region 823 (for example, a distance between the centers of gravity) is obtained. The distance is a distance between one bright spot 81 corresponding to the third region 823 on the corrected inspection image 8 c and a bright spot corresponding to the one bright spot 81 on the reference image 732. When the distance is larger than the predetermined distance, it is determined that a discharge failure of oblique discharge has occurred at the discharge port corresponding to the one bright spot 81. The occurrence of the ejection failure is notified to an operator or the like through the notification unit 79 (see FIG. 4). On the other hand, when the distance is equal to or less than the predetermined distance, the processing liquid from the discharge port corresponding to the one bright spot 81 is discharged in a direction slightly shifted from the designed discharge direction by a shift amount within an allowable range. It is determined that At this time, notification to the worker or the like through the notification unit 79 is not performed.

  The first region 821 on the right side on the difference image 82 also corresponds to one bright spot on the reference image 732, and the bright spot 81 does not exist at a position corresponding to the bright spot on the corrected inspection image 8c. It shows that. Since the third region 823 does not exist in the vicinity of the first region 821, the pass / fail judgment unit 752 has a non-ejection failure in which the treatment liquid is not ejected at the ejection port corresponding to the first region 821. Determined. The occurrence of the ejection failure is notified to an operator or the like through the notification unit 79 (see FIG. 4).

  As described above, the quality determination unit 752 of the determination unit 75 determines the quality of the ejection operation at each of the plurality of ejection ports 314a to 314d based on the difference between the reference image 732 and the corrected inspection image 8c. Thereby, the quality determination of discharge operation can be simplified. Further, the quality determination unit 752 sets the above-described plurality of normal ejection determination frames 85 and the like after correcting the image shift of the inspection image 8, or obtains the difference between the above-described reference image 732 and the inspection image 8. Then, the quality of the discharge operation is determined. Thereby, the positional deviation from the design inspection position of the discharge head 31 in the inspection region can be corrected, and the inspection accuracy of the discharge operation at the plurality of discharge ports 314a to 314d can be improved.

  The correction of the image shift of the inspection image 8 may be performed by correcting the inspection image 8 by image data processing, and after the ejection head 31 is positioned at the design inspection position, a plurality of bright spots 81 are re-photographed and re-examined. You may carry out by acquiring an acquisition test | inspection image.

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

  In the above-described discharge inspection unit 5, when a discharge determination frame is set in the corrected inspection image 8 c by the determination frame setting unit 74, the normal discharge determination frame 85 is always set, but the discharge determination other than the normal discharge determination frame 85 is performed. The frame need not necessarily be set. In the ejection inspection unit 5, the above-described normal ejection determination frame 85 and the difference image 82 are always used for the quality determination of the ejection operation performed after the image shift is corrected based on the reference image 732 and the inspection image 8. It is not limited to a thing, You may carry out by various methods.

  In the above description, the non-ejection and oblique ejection of the processing liquid are determined as ejection failures by the pass / fail determination unit 752, but other ejection operations may also be determined as ejection failures. For example, there is a possibility that droplets ejected from the ejection head 31 are split 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 at the discharge port. When it is determined that the discharge of a very small droplet is defective, for example, in the inspection image 8, a case where one bright spot 81 is detected in the normal discharge determination frame 85 is determined as normal discharge, and the normal discharge determination frame 85 is determined. A case in which a plurality of bright spots 81 are detected is determined as an ejection failure. Alternatively, in the difference image 82, a case where a third area 823 smaller than normal is detected in the vicinity of the first area 821 is determined as ejection failure.

  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 above-described inspection area may be set in an area other than above the standby pod 4. In this case, the light emission part 51 and the imaging part 52 are arrange | positioned in the vicinity of the said test | inspection area | region.

  The plurality of discharge ports of the discharge head 31 do not necessarily need to include a plurality of discharge port arrays arranged in parallel to each other. In addition, the head moving mechanism that moves the ejection head 31 between the upper side of the substrate 9 and the inspection region does not necessarily need to be a mechanism that rotates the ejection head 31. For example, the ejection head 31 moves linearly. It may be a mechanism.

  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 reference image storage unit 731, and the determination unit 75 may be used as a discharge inspection apparatus that is independent from other configurations of the substrate processing apparatus 1. The discharge inspection apparatus is used for, for example, inspecting the operation of discharging liquid from a plurality of discharge ports in an apparatus that discharges liquid from a plurality of discharge ports to the various substrates described above.

  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 8,8c Inspection image 9 Substrate 21 Substrate holding part 31 Discharge head 35 Head moving mechanism 51 Light emission part 52 Imaging part 75 Determination part 81 Bright spot 82 Difference image 85 Normal discharge determination frame 313a-313d Discharge port array 314a ˜314d Discharge port 352 Rotating shaft 510 Planar light 731 Reference image storage unit 732 Reference image 751 Misalignment correction unit 752 Pass / fail judgment unit

Claims (8)

A substrate processing apparatus,
A substrate holder for holding the substrate;
An ejection head that performs a predetermined process on the substrate by ejecting liquid toward the substrate from a plurality of ejection ports above the substrate;
A head moving mechanism for moving the ejection head from above the substrate to the inspection region;
A discharge inspection device for inspecting a liquid discharge operation from the plurality of discharge ports of the discharge head;
With
The discharge inspection device comprises:
By emitting light along a predetermined light existence surface, a plurality of flying bodies that are liquids ejected from the plurality of ejection ports of the ejection head located in the inspection region pass through the light existence surface. A light emitting unit for irradiating light to the plurality of flying objects,
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;
An image acquired by the imaging unit while emitting light from the light emitting unit in a state where liquid is normally ejected from the plurality of ejection ports of the ejection head located at a predetermined design inspection position in the inspection region. A reference image storage unit for storing a reference image;
Based on the reference image and the inspection image, the relative displacement of the inspection image with respect to the reference image due to the difference between the position of the ejection head and the design inspection position when the inspection image is acquired is corrected, A determination unit for determining the quality of the discharge operation at the plurality of discharge ports;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
A plurality of liquid jets appearing on a plurality of flying objects that eject the liquid from the plurality of ejection openings after moving the ejection head to the design inspection position based on the reference image and the inspection image, and pass through the light existence surface. By re-acquisition of the inspection image including the bright spot, correction of the relative shift by the determination unit is performed,
The substrate processing apparatus, wherein the determination unit determines whether the discharge operations at the plurality of discharge ports are good or not based on the re-acquired inspection image. The substrate processing apparatus according to claim 1, wherein:
The plurality of discharge ports include a plurality of discharge port arrays each of which is a set of discharge ports arranged linearly in the discharge port arrangement direction,
The substrate processing apparatus, wherein the plurality of discharge port arrays are arranged in a direction inclined with respect to the discharge port arrangement direction. A substrate processing apparatus according to any one of claims 1 to 3,
The substrate processing apparatus, wherein the ejection head is rotated about a predetermined rotation axis by the head moving mechanism to move between the upper side of the substrate and the inspection region. The substrate processing apparatus according to claim 1, wherein:
The substrate processing apparatus, wherein an imaging direction in the imaging unit is inclined with respect to a plane perpendicular to a predetermined ejection direction of the plurality of flying objects. A substrate processing apparatus according to any one of claims 1 to 5,
The substrate processing apparatus, wherein the light existence surface is inclined with respect to a plane perpendicular to a predetermined ejection direction of the plurality of flying objects. A substrate processing apparatus according to any one of claims 1 to 6,
The discharge inspection apparatus further includes a determination frame setting unit that sets a plurality of normal discharge determination frames corresponding to the plurality of discharge ports on the inspection image,
After the determination unit corrects the shift of the inspection image, the determination unit acquires bright spot presence / absence information in each normal discharge determination frame, and based on the presence / absence information, in the discharge port corresponding to each normal discharge determination frame A substrate processing apparatus for determining whether a discharge operation is good or bad. A substrate processing apparatus according to any one of claims 1 to 6,
The determination unit, after correcting the shift of the inspection image, determines whether the discharge operation at each of the plurality of discharge ports is good or not based on a difference between the reference image and the inspection image. Processing equipment.

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