Overview
Due to the expansion in the use of electro-optical components that are now common place in both telecommunications and display technologies, epitaxy is emerging as a key technique for component production. Epitaxy is the process of depositing very thin layers of semiconductor materials onto the surface of a single crystal substrate. Each crystal layer is known as an epilayer.

Surface Roughness
Surface texture is a vitally important parameter in specifying the quality of epitaxial semiconductors for both customers and suppliers. With the current drive for ever smaller circuits to be printed on wafers, the tolerances for roughness are becoming tighter. Surface finish for epiwafers is specified in nm, this requires a system with very low noise and high resolution be used to measure them.