| 摘要 |
PURPOSE:To detect the relative position between 1st and 2nd objects without having the influence of disturbance by determining the position with respect to the value of the correlation between the shapes of the light intensity distributions of at least >=2 luminous fluxes having the position information between the 1st and 2nd objects. CONSTITUTION:Incident luminous fluxes 101a, 101b are formed by collimating the luminous fluxes from a light emitting source to collimated beams of light by a collimator lens. Mask alignment mark pairs 103a, 103b are formed on a mask 102 which receives the incident luminous fluxes 101a, 101b. Wafer alignment mark pairs 103a, 103b are formed on a wafer 103. The luminous fluxes 104a, 104b have alignment information by passing the mark pairs 102a, 102b and the mark pairs 103a, 103b. Photoelectric converting elements 105a, 105b receive the luminous fluxes 104a, 104b and a signal processing section 106 process the outputs of the elements 105a, 105b. The position relation between the two objects is exactly determined even in such a case in which the shapes of the light intensity distributions of the luminous fluxes detected in this way are changed by the influence of noises, etc. |
