Substrate inspection apparatus and substrate inspection method

1. A substrate inspection apparatus, comprising:

a rotator that holds and rotates a substrate having a coating film formed on a surface;

a light irradiator that irradiates light to the surface of the substrate;

photoelectric converter that receives specularly reflected light from the surface of the substrate and captures an image of a scanning line having at least a length of the radius of the substrate in a main scanning direction parallel to a radial direction of the substrate from a center of rotation of the substrate; and

an image processor that generates a two-dimensional image by arranging images captured by the photoelectric converter during one turn of the substrate in a sub scanning direction perpendicular to the main scanning direction and judges whether an edge line of the coating film is good or bad using a judgment band set in parallel to the sub scanning direction for the two-dimensional image,

wherein the image processor includes:

an edge detector that divides an image included in the judgment band out of the two-dimensional image into a plurality of block images in the sub scanning direction and detects whether or not each block image includes the edge of the coating film; and

a good and bad judgment unit that judges whether the edge line of the coating film is good or bad based on the number of the edge-detected block images by the edge detector.

2. The substrate inspection apparatus according to claim 1 , wherein the edge detector divides the image such that the block images adjacent to each other partly overlap in the sub scanning direction.

3. The substrate inspection apparatus according to claim 1 , wherein the image processor specifies the edge line included in the two-dimensional image, calculates a changing point based on the presence or absence of the edge line within the width of the judgment band and judges an edge defect in the absence of the edge line.

4. The substrate inspection apparatus according to claim 1 , wherein:

a plurality of coating films are laminated on the surface of the substrate;

judgment bands are set in correspondence with the respective coating films; and

the image processor judges whether an edge line of each coating film is good or bad using the judgment band corresponding to each coating film.

5. A substrate inspection apparatus, comprising:

a rotator that holds and rotates a substrate having a coating film formed on a surface;

a light irradiator that irradiates light to the surface of the substrate;

a photoelectric converter that receives specularly reflected light from the surface of the substrate and captures an image of a scanning line having at least a length of the radius of the substrate in a main scanning direction parallel to a radial direction of the substrate from a center of rotation of the substrate; and

an image processor that generates a two-dimensional image by arranging images captured by the photoelectric converter during one turn of the substrate in a sub scanning direction perpendicular to the main scanning direction and judges whether an edge line of the coating film is good or bad using a judgment band set in parallel to the sub scanning direction for the two-dimensional image,

wherein the scanning line captured by the photoelectric converter has a length which is the sum of the radius of the substrate and a first length in the main scanning direction from the center of rotation.

6. The substrate inspection apparatus according to claim 5 , wherein the scanning line captured by the photoelectric converter extends a second length in a direction opposite to the main scanning direction from the center of rotation.

7. A substrate inspection apparatus, comprising:

a rotator that holds and rotates a substrate having a coating film formed on a surface;

a light irradiator that irradiates light to the surface of the substrate;

a photoelectric converter that receives specularly reflected light from the surface of the substrate and captures an image of a scanning line having at least a length of the radius of the substrate in a main scanning direction parallel to a radial direction of the substrate from a center of rotation of the substrate; and

an image processor that generates a two-dimensional image by arranging images captured by the photoelectric converter during one turn of the substrate in a sub scanning direction perpendicular to the main scanning direction and judges whether an edge line of the coating film is good or bad using a judgment band set in parallel to the sub scanning direction for the two-dimensional image,

wherein the scanning line captured by the photoelectric converter extends a length in a direction opposite to the main scanning direction from the center of rotation.

8. A substrate inspection method, comprising:

a capturing step of capturing an image of a scanning line having at least a length of the radius of a substrate having a coating film formed on the surface in a main scanning direction parallel to a radial direction of the substrate from a center of rotation of the substrate by irradiating light to the surface of the substrate while rotating the substrate, and receiving specularly reflected light from the surface of the substrate;

an image generating step of generating a two-dimensional image by arranging images obtained by repeating the capturing step during one turn of the substrate in a sub scanning direction perpendicular to the main scanning direction; and

a judging step of judging whether an edge line of the coating film is good or bad using a judgment band set in parallel to the sub scanning direction for the two-dimensional image,

wherein the judging step includes: dividing an image included in the judgment band out of the two-dimensional image into a plurality of block images in the sub scanning direction and detecting whether or not each block image includes the edge of the coating film, and judging whether the edge line of the coating film is good or bad based on the number of the edge-detected block images.

9. The substrate inspection method according to claim 8 , wherein the judging step includes dividing the image such that the block images adjacent to each other partly overlap in the sub scanning direction.

10. The substrate inspection method according to claim 8 , wherein the image generating step includes specifying the edge line included in the two-dimensional image, calculating a changing point based on the presence or absence of the edge line within the width of the judgment band, and judging an edge defect in the absence of the edge line.

11. The substrate inspection method according to claim 8 , wherein the scanning line captured in the capturing step has a length which is the sum of the radius of the substrate and a first length in the main scanning direction from the center of rotation.

12. The substrate inspection method according to claim 11 , wherein the scanning line captured in the capturing step extends a second length in a direction opposite to the main scanning direction from the center of rotation.

13. The substrate inspection method according to claim 8 , wherein the scanning line captured in the capturing step extends a length in a direction opposite to the main scanning direction from the center of rotation.

14. The substrate inspection method according to claim 8 , wherein:

a plurality of coating films are laminated on the surface of the substrate; and

in the judging step, a plurality of judgment bands are set in correspondence with the respective coating films; and

the step of judging whether an edge line of each coating film is good or bad uses the respective judgment band corresponding to each coating film.