Ejection inspection apparatus and substrate processing apparatus

1. An ejection inspection apparatus for inspecting an operation of ejecting a liquid from a plurality of outlets, comprising:

a light emitter for emitting planar light along a predetermined light existing plane to irradiate a plurality of flying droplets passing through said light existing plane with the planar light, said plurality of flying droplets being a liquid ejected from a plurality of outlets;

an image capturing device for capturing an image of said plurality of flying droplets while said plurality of flying droplets passes through said light existing plane to acquire an inspection image that includes a plurality of bright dots appearing on said plurality of flying droplets; and

a controller programmed to:

obtain said inspection image and set, in said inspection image, a plurality of normal ejection determination frames corresponding respectively to said plurality of outlets on the basis of coordinates of a bright dot reference position of each of said plurality of bright dots, said bright dot reference position being a point of intersection of said light existing plane and a center line of ejection that extends from each of said plurality of outlets in a design ejection direction of said plurality of flying droplets; and

acquire existence information that indicates whether or not a bright dot exists in each of said plurality of normal ejection determination frames and determining quality of an ejection operation of an outlet corresponding to said each normal ejection determination frame on the basis of said existence information.

2. The ejection inspection apparatus according to claim 1 , wherein

an imaging direction of said image capturing device inclines relative to a plane perpendicular to a predetermined direction of ejection of said plurality of flying droplets.

3. The ejection inspection apparatus according to claim 1 , wherein

said light existing plane inclines relative to a plane perpendicular to a predetermined direction of ejection of said plurality of flying droplets.

4. The ejection inspection apparatus according to claim 1 , wherein

said plurality of outlets are linearly arranged, and

said controller is further programmed to set positions of said plurality of normal ejection determination frames on the basis of positions of bright dots that are located at opposite ends among said plurality of bright dots included in said inspection image.

5. The ejection inspection apparatus according to claim 1 , wherein said controller is further programmed to:

set a plurality of oblique ejection determination frames respectively around said plurality of normal ejection determination frames, and

determine occurrence or non-occurrence of an oblique ejection at an outlet corresponding to each of said plurality of oblique ejection determination frames on the basis of existence information indicating whether or not a bright dot exists in said each oblique ejection determination frame.

6. The ejection inspection apparatus according to claim 1 , wherein said controller is further programmed to:

set a single oblique ejection determination frame around said plurality of normal ejection determination frames, and

determine occurrence or non-occurrence of an oblique ejection on the basis of existence information indicating whether or not a bright dot exists in said oblique ejection determination frame.

7. The ejection inspection apparatus according to claim 1 , wherein

said controller is further programmed to obtain a centroid of each of said plurality of bright dots in said inspection image and acquires existence or non-existence of the centroid of a bright dot in said each normal ejection determination frame as said existence information indicating whether or not a bright dot exists in said each normal ejection determination frame.

8. The ejection inspection apparatus according to claim 1 , wherein said controller is further programmed to correct a size of each of said plurality of bright dots in said inspection image on the basis of a length of an inspection distance that is a distance between said image capturing device and said bright dot reference position, and

said existence information is information indicating whether or not at least a portion of a bright dot corrected by said controller exists in said each normal ejection determination frame.

9. The ejection inspection apparatus according to claim 8 , wherein said controller is further programmed to perform correction to decrease the size of said each bright dot as said inspection distance decreases.

10. The ejection inspection apparatus according to claim 8 , wherein

said controller is further programmed to perform correction to decrease the size of said each bright dot as a difference between said inspection distance and an in-focus distance of said image capturing device increases.

11. The ejection inspection apparatus according to claim 8 , wherein said controller is further programmed to reduce a size of said each bright dot in said ejection direction as a difference between an irradiation distance and a distance from said light emitter to a light thinnest position increases, said irradiation distance being a distance between said light emitter and said bright dot reference position in a direction parallel to an optical axis between said light emitter and said bright dot reference position, and said light thinnest position being a position at which the light emitted from said light emitter has a smallest thickness in said ejection direction.

12. The ejection inspection apparatus according to claim 1 , wherein said controller is further programmed to:

provisionally set, in said inspection image, a normal ejection determination frame of a predetermined size in correspondence with each of said plurality of outlets, said normal ejection determination frame centering on said bright dot reference position; and

adjust each normal ejection determination frame on the basis of an inspection distance that is a distance between said bright dot reference position and said image capturing device.

13. The ejection inspection apparatus according to claim 12 , wherein said controller is further programmed to perform adjustment to decrease the size of said each normal ejection determination frame as said inspection distance increases.

14. The ejection inspection apparatus according to claim 12 , wherein said controller is further programmed to perform adjustment to decrease the size of said each normal ejection determination frame as a difference between said inspection distance and an in-focus distance of said image capturing device increases.

15. The ejection inspection apparatus according to claim 12 , wherein said controller is further programmed to reduce the size of said each normal ejection determination frame in said ejection direction as a difference between an irradiation distance and a distance between said light emitter and a light thinnest position increases, said irradiation distance being a distance between said light emitter and said bright dot reference position in a direction parallel to an optical axis between said light emitter and said bright dot reference position, and said light thinnest position being a position at which the light emitted from said light emitter has a smallest thickness in said ejection direction.

16. A substrate processing apparatus comprising:

a substrate holder for holding a substrate;

an ejection head for ejecting a liquid from a plurality of outlets toward said substrate and performing predetermined processing on said substrate; and

an ejection inspection apparatus for inspecting an operation of said ejection head ejecting a liquid from said plurality of outlets,

said ejection inspection apparatus including:

a light emitter for emitting planar light along a predetermined light existing plane to irradiate a plurality of flying droplets passing through said light existing plane with the light, said plurality of flying droplets being the liquid ejected from said plurality of outlets;

an image capturing device for capturing an image of said plurality of flying droplets while said plurality of flying droplets passes through said light existing plane to acquire an inspection image that includes a plurality of bright dots appearing on said plurality of flying droplets; and

a controller programmed to:

obtain said inspection image and setting, in said inspection image, a plurality of normal ejection determination frames corresponding respectively to said plurality of outlets on the basis of coordinates of a bright dot reference position of each of said plurality of bright dots, said bright dot reference position being a point of intersection of said light existing plane and a center line of ejection that extends from each of said plurality of outlets in a design ejection direction of said plurality of flying droplets; and

acquire existence information that indicates whether or not a bright dot exists in each of said plurality of normal ejection determination frames and determining quality of an ejection operation of an outlet corresponding to said each normal ejection determination frame on the basis of said existence information.

17. The substrate processing apparatus according to claim 16 , further comprising

a protection liquid supply for supplying a protection liquid onto said substrate to form a protection liquid film that covers a plurality of design landing positions, on said substrate, of the liquid ejected from said plurality of outlets,

wherein processing for cleaning said substrate is performed by said plurality of outlets ejecting fine droplets of said liquid serving as a cleaning liquid and said fine droplets transferring kinetic energy to said substrate through said protection liquid film.

18. The substrate processing apparatus according to claim 16 , wherein

said controller is further programmed to correct a size of each of said plurality of bright dots in said inspection image on the basis of a length of an inspection distance that is a distance between said image capturing device and said bright dot reference position, and

said existence information is information indicating whether or not at least a portion of a bright dot corrected by said controller exists in said each normal ejection determination frame.

19. The substrate processing apparatus according to claim 16 , wherein said controller is further programmed to:

provisionally set, in said inspection image, a normal ejection determination frame of a predetermined size in correspondence with each of said plurality of outlets, said normal ejection determination frame centering on said bright dot reference position; and

adjust each normal ejection determination frame on the basis of an inspection distance that is a distance between said bright dot reference position and said image capturing device.

20. A substrate processing apparatus comprising:

a substrate holder for holding a substrate;

a protection liquid supply for supplying a protection liquid onto said substrate to form a protection liquid film that covers a portion of said substrate;

an ejection head for ejecting a liquid from a plurality of outlets toward said protection liquid film formed on said substrate to perform predetermined processing on said substrate; and

an ejection inspection apparatus for inspecting an operation of said ejection head ejecting a liquid from said plurality of outlets,

said ejection inspection apparatus including:

a light emitter for emitting planar light along a predetermined light existing plane to irradiate a plurality of flying droplets passing through said light existing plane with the planar light, said plurality of flying droplets being the liquid ejected from said plurality of outlets;

an image capturing device for capturing an image of said plurality of flying droplets while said plurality of flying droplets passes through said light existing plane to acquire an inspection image that includes a plurality of bright dots appearing on said plurality of flying droplets; and

a controller programmed to:

obtain said inspection image and setting, in said inspection image, a protection-liquid-film ejection determination frame and an outer ejection determination frame, said protection-liquid-film ejection determination frame corresponding to said protection liquid film formed on said substrate, and said outer ejection determination frame surrounding said protection-liquid-film ejection determination frame; and

acquire existence information indicating whether or not a bright dot exists in said outer ejection determination frame and determining occurrence or non-occurrence of landing of the liquid in an area outside said protection liquid film on the basis of said existence information.

21. The substrate processing apparatus according to claim 20 , wherein

said protection-liquid-film ejection determination frame in said inspection image is set on the basis of positions of peripheral outlets that are located in a peripheral portion of an outlet arrangement area in which said plurality of outlets are provided in said ejection head, a position of a peripheral portion of said protection liquid film on said substrate, and a position of said light existing plane located between said peripheral outlets and said protection liquid film, and

processing for cleaning said substrate is performed by said plurality of outlets ejecting fine droplets of said liquid serving as a cleaning liquid and by said fine droplets transferring kinetic energy to said substrate through said protection liquid film.