In high numerical aperture (NA) subsurface imaging, we can obtain higher resolution in selected directions at the expense of resolutions in other directions, utilizing the vectorial properties of polarized light. In this work, we propose an image fusion framework that produces a single image with higher resolution and image quality in all directions by processing multiple images acquired by varying the polarization direction of the linearly polarized input laser light.

A novel method for obtaining diffraction limited high resolution images, and increased signal to noise ratio (SnR), for imaging and probing silicon based complementary metal oxide semiconductor field effect transistor (CMOS, and MOSFET) integrated circuits (IC), is presented. The improved imaging is based on the sub wavelength features’ asymmetric layout, which is dictated by the lithography design rules constrain in CMOS IC and their interactions with polarized light. This asymmetry in layout and the inherent stress engineering on the CMOS IC, produce both dichroism and birefringence in silicon (Si). An elegant design enabled us to obtain two images with orthogonal polarization detection to take advantages of the dichroism and birefringence in Si based CMOS IC. Differential Polarization Image (DPI) is obtained by subtracting the two orthogonal polarization resolved images. On infrared emission microscopes (IREM), DPI in optical imaging mode and DPI plus probing [DPIP] in emission mode, showed 2X or more in terms of optical resolution (imaging mode) and 2X or more SnR (emission-probing mode) improvements. Striking images in probing mode, revealing previously “invisible” emission, were demonstrated.

Optical microscopy techniques used by forensic analysts are shown to have application to failure analysis problems. Proper set up of the optical microscope is reviewed, including the correct use of the field diaphragm and the aperture diaphragm. Polarized light microscopy, bright and dark field methods, refractive index liquids, and a particle reference atlas are used to identify contamination found on semiconductor products.