Investigation of SiGe/Si heterostructures using state-of-the-art Auger Nanoprobes

The capabilities of nano-Auger were assessed for the characterization of SiGe multilayers epitaxially grown on Si(001) wafers. Reference sample consisting in stack of (300–500)-nm thick SiGe layers with a Ge content increasing in discrete steps from 6 to 30 % (as determined by X-ray diffraction) were used to that end. Composition measurements were performed on cross-sections with localized Auger Electron Spectroscopy using point analysis. The promising results obtained should enable in the near future high performance Auger mapping of real devices. The effect of native oxide removal either by argon sputtering or by HF etching was also addressed. Complementary results were otherwise obtained with Auger depth profiling using argon sputtering with Zalar rotation.