The planar shape measuring method in the phase shift interference fringe simultaneous imaging device

摘要

PROBLEM TO BE SOLVED: To provide a plane shape measuring method capable of measuring a surface undulation shape of a surface to be inspected highly accurately even if reflectances of surface to be inspected used for calculating bias and amplitude beforehand and a surface to be inspected used for measuring the shape are different or the sample light intensity is different, when reducing, by numerical operation, an error at the shape calculation time generated by the difference of bias and amplitude between branch phase shift interference fringes generated by splitting an original beam comprising reflected light from a reference surface and the surface to be inspected, in a phase shift interference fringe simultaneous measuring device. ;SOLUTION: In this phase shift interference fringe simultaneous measuring device, shape calculation is performed relative to an error at the shape calculation time generated by the difference of the bias and the amplitude between branch phase shift interference fringes generated by splitting the original beam comprising reflected light from the reference surface and the inspection surface, by newly taking into consideration the intensity ratio of sample light at the bias and amplitude calculation time and at the shape measuring time, namely, the reflectance ratio.;COPYRIGHT: (C)2003,JPO