Poly-crystalline silicon layers on silicon oxide

Another semiconductor example demonstrates the investigation of quite thin films with infrared reflectance spectroscopy. As sketched the sample consists of a poly-crystalline silicon layer (which may serve as the gate electrode in a transistor) separated by a thin insulating SiO2 layer from the silicon substrate.

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The obtained thicknesses are 14 nm for the SiO2 layer and 238 nm for the poly-crystalline silicon film.

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