A scanning electron microscope with EDX detector (energy-dispersive X-ray analysis) and an electron beam micro-probe (EPMA; wavelength-dispersive X-ray analysis) is available for X-ray spectroscopy.
Benefits of both methods:
- Qualitative and quantitative chemical element analysis
- All elements except H, He, Be and Li
- High lateral and vertical resolution (~ 0.5 µm)
- High absolute accuracy
- Low detection limit of 0.1 ... 0.01 %
- Film thickness determination is possible (< 0.5 ... 1 µm
Electron beam scanning makes it possible to record element distribution images (see above). Angled or cross-section polishes are sampled for the measurement of depth profiles. A combined determination of film thickness and composition for thin films (≤ 500 nm) is possible, as well as non-destructive testing by determining the overall mass distribution. Under certain conditions, this even works for 2 or 3-layer systems. Fraunhofer IST has extensive empirical values for the quantitative analysis of materials containing metals in combination with “light” elements (B, C, N, O, F).
Due to its high degree of measuring automation, EPMA is also suitable for the examination of large sample series (50–100 pieces) or for position-dependent measurement (line scans, mappings), for instance in quality assurance or the analysis of defects.