Topography characterization of a deep grating using near-field imaging.
Using near-field optical microscopy at the wavelength of 633 nm, we image light intensity distributions at several distances above an approximately 2-microm-deep and a 1-microm-period glass grating illuminated from below under the condition of total internal reflection. The intensity distributions are numerically modeled, and an inversion procedure based on a least-squares-fit optimization is employed to extract the grating geometry from the optical images.
Gregersen
Niels
N
Research Center COM, NanoDTU, Technical University of Denmark, Building 345V, DK-2800 Kgs. Lyngby, Denmark. ngr@com.dtu.dk
Tromborg
Bjarne
B
Volkov
Valentyn S
VS
Bozhevolnyi
Sergey I
SI
Holm
Johan
J