Patent ID: 8532364

Claim:
Apparatus for inspecting a semiconductor wafer, comprising: a platform for supporting a wafer to be inspected; a light source; a plurality of light sensors; a dome having a convex diffusely reflecting inner surface positioned facing the platform; and a data processing unit; wherein the platform, light sensors, plurality of light sensors and dome are relatively arranged so that the light sensors can simultaneously acquire a set of images from respective different angles of view of a surface of the wafer supported on the platform and simultaneously illuminated both by hard light from the light source incident sideways on and directly reflected from the wafer without reflection from the inner surface and by soft light from the light source incident substantially uniformly from above and indirectly reflected from the wafer after being first reflected from the inner surface; and wherein the data processing unit is connected to the light sensors and adapted to receive data representative of the images acquired by the light sensors, to compare each image with a corresponding image of another set of images of a surface of another wafer previously acquired by the same light sensors from the same respective different angles of view, and to automatically detect a defect based on the image comparison.