Optical Microscopy

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Optical Microscopy is a powerful yet often under utilized tool. The use of visible light to evaluate a sample can provide valuable information about  device structure and composition.  In many situations, microscopic analysis alone can supply the information needed to solve the problem or direct the analyst along the most efficient path to gain additional information.  The three common types of optical microscopy are Brightfield Illumination, Darkfield Illumination, and Nomarski Imaging.

Brightfield illumination is the most commonly used mode. In this mode, light directly striking the surface is reflected based on the sample’s composition and topography.

Darkfield illumination is a tool for viewing particles, edges, or other changes occurring on a sample’s surface.  With this process, the center of the light cone is blocked allowing only light scattering along the surface at a low angle to illuminate the field of view.

Nomarski imaging is useful for viewing shallow defects such as etch pits and cracks.  It  is a form of interference contrast that utilizes polarized light passed through a prism to view the sample.

Silicon Cert Laboratories uses optical microscopy to inspect all submitted samples and will direct our customers along the most efficient course of analysis. SCL can provide digital images in a variety of formats from a full range of microscopes along with dimension measurements using a toolmakers measuring microscope calibrated to a traceable standard.   Contact our engineering expertise for more information about optical microscopy.