Patent ID: 6954268

Claim:
A defect inspection apparatus comprising: an inspection section which inspects a front surface and a rear surface off a sample; a control section which processes image data of the front surface and the rear surface of the sample obtained by the inspection section; a front surface moving section provided in the inspection section which moves the sample for inspection of the front surface; a rear surface moving section provided in the inspection section which moves the sample for inspection of the rear surface; and a front surface illumination section and a rear surface illumination section which respectively illuminate the front surface and the rear surface for inspection; a front surface image pickup section and a rear surface image pickup section which respectively pick up an image of the illuminated front surface and an image of the illuminated rear surface; wherein at least one of: (i) respective incidence angles of the front surface illumination section and the rear surface illumination section on the sample, and (ii) respective image pickup angles of the front surface image pickup section and the rear surface image pickup section with respect to the sample, are changeable; wherein the rear surface illumination section and the rear surface image pickup section are arranged along moving path of the rear surface moving section to inspect the rear surface of the sample; wherein at least the rear surface illumination section comprises a linear light source which irradiates a linear parallel light beam to the rear surface of the sample at a predetermined incidence angle, and at least the rear surface image pickup section comprises a line sensor camera which picks up the image of the rear surface illuminated by the light beam from the linear light source; and wherein the sample is moved to and from the front surface moving section via at least the rear surface moving section, and the rear surface of the sample is inspected while the rear surface moving section moves the sample.