Near-field scanning optical microscope studies of the anisotropic stress variations in patterned SiN membranes
15 January 2002
A near-field scanning optical microscope (NSOM) is used in transmission to study the anisotropic stress variations in SiN membranes, nominally 50 nm thick, containing arrays of submicron size holes. A polarization modulation technique is employed in combination with the NSOM to obtain quantitative measurements of the stress induced optical anisotropy on a similar to 100 nm scale. A method is developed to remove the dichroic contribution from the measured retardance in order to determine stress variation. Stress patterns observed in the images provide insight into how the membrane relaxes in response to the patterning process. (C) 2002 American Institute of Physics.