Scanning Raman spectroscopy for characterizing compositionally spread films

TL;DR

This paper demonstrates the use of scanning Raman spectroscopy as a non-destructive method to characterize compositionally spread La1-xSrxMnO3 thin films, revealing structural variations, distortions, and phase coexistence.

Contribution

It introduces a novel application of scanning Raman spectroscopy for non-destructive analysis of compositionally graded thin films.

Findings

Raman spectra vary with composition, indicating structural and distortion changes.

Coexisting phases are identified at specific compositions.

Disorder and strain effects are observable through Raman analysis.

Abstract

Composition-spread La1-xSrxMnO3 thin films were prepared by pulsed laser deposition technique from LaMnO3 and SrMnO3 targets. The films were epitaxial with a continuous variation of the out of plane lattice parameter along the direction of composition gradient. Scanning Raman spectroscopy has been employed as a non-destructive tool to characterize the composition-spread films. Raman spectra showed the variation of the structural, Jahn Teller distortions and the presence of coexisting phases at particular compositions that are in agreement with the previous observation on the single crystal samples. Raman spectra on the continuous composition-spread film also reveal the effect of disorder and strain on the compositions.