Towards nanometric resolution in multilayer depth profiling: a comparative study of RBS, SIMS, XPS and GDOES

Abstract

An increasing amount of effort is currently being directed towards the development of new functionalized nanostructured materials (i.e., multilayers and nanocomposites). Using an appropriate combination of composition and microstructure, it is possible to optimize and tailor the final properties of the material to its final application. The analytical characterization of these new complex nanostructures requires high-resolution analytical techniques that are able to provide information about surface and depth composition at the nanometric level. In this work, we comparatively review the state of the art in four different depth-profiling characterization techniques: Rutherford backscattering spectroscopy (RBS), secondary ion mass spectrometry (SIMS), X-ray photoelectron spectroscopy (XPS) and glow discharge optical emission spectroscopy (GDOES). In addition, we predict future trends in these techniques regarding improvements in their depth resolutions. Subnanometric resolution can now be achieved in RBS using magnetic spectrometry systems. In SIMS, the use of rotating sample holders and oxygen flooding during analysis as well as the optimization of floating low-energy ion guns to lower the impact energy of the primary ions improves the depth resolution of the technique. Angle-resolved XPS provides a very powerful and nondestructive technique for obtaining depth profiling and chemical information within the range of a few monolayers. Finally, the application of mathematical tools (deconvolution algorithms and a depth-profiling model), pulsed sources and surface plasma cleaning procedures is expected to greatly improve GDOES depth resolution.

Molecular Organization of the Nanoscale Surface Structures of the Dragonfly Hemianax papuensis Wing Epicuticle

“…Conversely, x-ray photoelectron spectroscopy (XPS) is capable of nanometer resolution in the z-dimension [48]–[51]. Depth-profiling XPS spectra obtained by alternating data acquisition and ion-beam etching were found to be dominated by carbon.…”

Large magneto-elastic anisotropy enhancement with temperature in composition-graded FeCoTa thin films

“…[11][12][13][14][15][16][17] For the determination of the average composition overall the samples, we employ a technique so-called radio frequency glow discharge optical emission spectroscopy (RF-GD-OES) to characterize. 18 A typical depth profile of the composition analysis based on RF-GD-OES for FeCoTa film with P Ta ¼ 60 W is shown in Fig. 1(b).…”

Materials characterization by synchrotron x-ray microprobes and nanoprobes

“…Rutherford backscattering (RBS), see Fig. 4, is used to determine the compositional depth profile by measuring the elastic backscattering of a beam of high-energy ions (usually α particles or, less commonly, protons) impinging on a sample (Galindo et al, 2010).…”