The electronic and optical properties of transparent conducting oxides (TCOs) are closely
linked to their crystallographic structure on a macroscopic (grain sizes) and microscopic
(bond structure) level. With the increasing drive towards using reduced film thicknesses in
devices and growing interest in amorphous TCOs such as n-type InGaZnO4 (IGZO), ZnSnO3
(ZTO), p-type CuxCrO2, or ZnRh2O4, the task of gaining in-depth knowledge on their crystal
structure by conventional X-ray diffraction-based measurements are becoming increasingly difficult.
We demonstrate the use of a focal shift based background subtraction technique for Raman
spectroscopy specifically developed for the case of transparent thin films on amorphous substrates.
Using this technique we demonstrate, for a variety of TCOs CuO, a-ZTO, ZnO:Al), how changes
in local vibrational mo