X-ray photoelectron spectroscopy study of the chemical interaction at the Pd/SiC interface

Abstract

In order to study the chemical interaction during interface formation between Pd and SiC, Pd layers of various thicknesses were deposited on structurally disordered SiC surfaces at 800 °C. The Pd/SiC interface, which plays a crucial role for many applications such as high power electronic devices and tristructural-isotropic (TRISO) nuclear fuels, was studied in situ by x-ray photoelectron spectroscopy. We find that after Pd deposition, Si–C and Si–Si bonds are broken in favor of the formation of not only Pd–Si but also Pd–C bonds. In addition, various silicon oxycarbide bonds are observed at the SiC surface and the Pd/SiC interface. These results are not only of relevance for the long-term stability of TRISO fuels but also for a variety of other applications, including Schottky-barrier-type contacts in electronic devices.