Abstract:
The double color interferometric microscope is developed for step height standards nanometrology traceable to meter definition via primary wave-length laser standards. The setup is based on 2 stabilized lasers to provide traceable measurements of highest possible resolution down to the physical limits of the optical instruments in sub-nanometer to micrometer range of the heights. The wavelength reference is He-Ne 633 nm stabilized laser, the secondary source is Blue-Green 488 nm grating stabilized laser diode. Accurate fringe portion is measured by modulated phase-shift technique combined with imaging interferometry and Fourier processing. Self-calibrating methods are developed to correct systematic interferometer errors.
