Automatic determination method of inspection region for substrate holding state abnormality inspection and substrate processing system

A substrate processing system comprising:

• a substrate holding unit configured to rotate a substrate being held in a substantially horizontal attitude;
• a processing control unit configured to add predetermined processing to the substrate in a state where the substrate holding unit is rotated;
• and
• an abnormality inspection unit configured to inspect abnormality of a holding state of the substrate by the substrate holding unit,
• the abnormality inspection unit including:
• an imaging unit configured to acquire a first image by photographing the substrate being held by the substrate holding unit from a horizontal direction;
• a cut out unit configured to cut out, from the first image, a second image corresponding to an inspection region positioned above the substrate being properly held by the substrate holding unit;
• and
• a determination unit configured to obtain a feature quantity indicating the holding state of the substrate by the substrate holding unit and to perform abnormality determination of the holding state based on the feature quantity on the second image,
• the substrate processing system further comprising:
• an inspection region determination unit configured to determine the inspection region for abnormality inspection of the holding state of the substrate, wherein
• the inspection region determination unit includes:
• an upper end surface confirmation unit configured to confirm an upper end surface of the substrate being normally held by the substrate holding unit in the first image;
• a vertical position determination unit configured to determine a position of the inspection region in a vertical direction based on a position of the upper end surface of the substrate in the first image having been confirmed by the upper end surface confirmation unit;
• and
• a horizontal position determination unit configured to, for a candidate of the inspection region for which the position in the vertical direction has been determined, obtain density at a rotation start time of the substrate holding unit, obtain a difference image integrated value being an integrated value of a difference absolute value with density of the same region in an initial state of the substrate holding unit, and determine a horizontal position of the inspection region based on the difference image integrated value having been obtained.