Ultrafast elemental mapping of materials combinatorial libraries and high-throughput screening samples via pulsed glow discharge optical emission spectroscopy

Combinatorial and high-throughput techniques have become well-established in materials science to aid in the accelerated discovery of novel functional materials. Thin film composition spreads are frequently used for this purpose by performing localized measurements and exploring different properties throughout the phase diagram. Nevertheless, the thin film composition map has to be determined to understand the behavior of the compound or alloy of interest. There are several established techniques that can give elemental composition maps of large areas but the total mapping time can range from several hours to tens of hours or more. Thus, faster elemental mapping techniques are needed. In this study, the applicability of GDOES elemental mapping towards combinatorial and high-throughput screening samples is explored by characterizing a CuNi thin film composition spread. Qualitative analysis images show that Cu and Ni composition gradients can be obtained in a matter of seconds. In addition, the use of reference materials allowed quantitative elemental analysis maps to be extracted from the emission intensity images. The images of emission intensities and curve fitting parameters are discussed. Finally, the GDOES results are compared to profiles obtained via EDX. The GDOES figures-of-merit relevant to elemental mapping are contrasted against selected alternative techniques from the literature to put the potential impact into perspective.