Micrometallurgy: a technique for examining the structure of binary-element thin films over a wide range of composition

We describe a procedure for producing thin-film TEM specimens containing a thickness and/or composition gradient, utilizing an out-of-contact mask at an appropriate distance from the substrate. Imaging and diffraction capabilities of the TEM are used to examine the local structure of the film; EELS or EDX analysis provides the local elemental composition. The procedure is illustrated by results obtained from two binary-alloy systems: Se–Te (which displays a complete range of solid solubility) and Sn–Ge (where mutual solubility is very low).