| 摘要 |
PROBLEM TO BE SOLVED: To accurately focus by suppressing a focus error which arises due to diffraction light (1) to accurately focus by a small, simple, low-cost configuration (2), and to more securely detect any defect of a minute structure (e.g., reticle) (3). SOLUTION: A focal position control method and a device are used for inspection targets in which first to sixth streams (1st to 6st) as a plurality of inspection areas are adjacent to one another having correlations, detect focal positions by using light reflected from each of the inspection target, and exerts focal position control based on the detection result. In the method and the apparatus, a focal position information group detected for one of the inspection areas is subjected to the arithmetic processing of polynominal approximation. Based on the arithmetic processing result, focal position control for an inspection area adjacent to the one inspection area is performed in the range of the depth of focus. COPYRIGHT: (C)2010,JPO&INPIT |
