| 摘要 |
PROBLEM TO BE SOLVED: To provide illumination subsystems for multi-spot wafer inspection.SOLUTION: One illumination subsystem includes a diffractive optical element 22 configured to separate an illumination light beam into multiple light beams, and a refractive lens array 28 positioned in a path of the multiple light beams. The refractive lens array 28 is configured to relay the laser beam waist at the diffractive optical element onto a wafer surface and to separately and simultaneously focus each of the multiple light beams to a wafer under inspection.SELECTED DRAWING: Figure 2 |
