Application of atomic-force microscopy to phase-shift masks
A.P. Ghosh, D.B. Dove, et al.
Microlithography 1992
Absolute optical ranging has been demonstrated by wavelength-multiplexed interferometry with a range resolution of 200 nm, well below the single-wavelength ambiguity. Two current- and temperature-tunable GaAlAs laser diodes (850 nm) provide an equivalent wavelength below 100 μm and a resolution of less than 200 nm. The achievement of such resolution provides the means for combining single- and multiple-wavelength interferometric measurements to achieve unambiguous distance measurement with nanometer resolution. The ranging system is also used to profile unambiguously an integrated circuit structure with a 2.5-μm surface topography. © 1989 Optical Society of America.
A.P. Ghosh, D.B. Dove, et al.
Microlithography 1992
J. Schneir, P.K. Hansma, et al.
Proceedings of SPIE 1989
M. Nonnenmacher, M.P. O'Boyle, et al.
Ultramicroscopy
M.P. O'Boyle, T.T. Hwang, et al.
Applied Physics Letters