Patent ID: 7289232

Claim:
A dimension measurement method comprising: irradiating a measurement mark with light, the measurement mark being formed on a sample on which a pattern to be measured is formed, the measurement mark comprising measurement patterns of the same shape as at least part of the pattern to be measured, the measurement patterns being arranged in a matrix constituted of measurement pattern columns which are repetitively disposed with a predetermined space in the direction of an arbitrary measurement direction which would provide a measurement target dimension of the pattern to be measured, said measurement pattern column being composed of the measurement patterns disposed with a predetermined period in the direction perpendicular to the measurement direction, and the light being fallen from the measurement direction; detecting reflected diffracted light from the measurement mark to measure intensity thereof; calculating a theoretical value of the intensity of the reflected diffracted light from a plurality of candidate values for the measurement target dimension; and outputting, as a measurement value of the measurement target dimension, the candidate value which provides a theoretical value most approximate to the measured intensity of the reflected diffracted light among the plurality of candidate values, wherein a relation between a wavelength of the light incident on the measurement mark and said period is adjusted so that the measurement mark generates the reflected diffracted light which is substantially the same as reflected diffracted light which would be generated when said pattern column is assumed to be a continuous line pattern.