Table 4: Contents of element on surface.

AnalysisRelative contents, atomic%
MethodDepthRubbed surfaceNon-rubbed surface
AlSiSnFeAlSiSnFe

AES3-4 nm7525n/dn/d100n/dn/dn/d
XPS4 nm82142291n/d9n/d
SEM-EDX1 μm74242trace9343n/d

n/d: not detected.
trace: less than 1%.