Abstract
We conducted laboratory-based HAXPES experiments with either a monochromatic Cr Kα or Ga Kα x-ray source to nondestructively perform chemical state analysis with bulk sensitivity, in comparison with conventional XPS using Mg Kα and Al Kα x-ray sources. To analyze the bulk-sensitive chemical states of silver and copper elements having a relatively small chemical shift in the Ag 3d5/2 and Cu 2p3/2 regions, we attempt to use Ag L3M4,5M4,5 and Cu KL2,3L2,3 Auger electrons with a large inelastic mean free path (IMFP). In this paper, the Ag 3d5/2 − Ag L3M4,5M4,5 and Ag 2p3/2 − Ag L3M4,5M4,5 modified Auger parameters were measured by Cr Kα excitation for thirteen silver-containing materials: Ag, Ag0.09P0.1Cu0.81, Ag0.6Cu0.4, Ag2O, Ag2O2, Ag2S, AgI, AgBr, AgCl, AgF, Ag2CO3, AgNO3, and Ag2SO4. The Cu 2p3/2 − Cu KL2,3L2,3 modified Auger parameter was also measured by Ga Kα excitation for five copper-containing materials: Cu, Cu0.6Zn0.4, Cu2O, CuBr, and CuO. The Wagner plot of the silver and copper materials were drawn with the obtained modified Auger parameters. The results indicate that the approach demonstrated here was effective in identifying the chemical states of the surface oxide layers formed by melting and subsequent solidification of a silver brazing alloy (Ag0.6Cu0.4).
