Thermal stability of amorphous SiOC/crystalline Fe composite

Abstract

We examined the thermal stability of amorphous silicon oxycarbide (SiOC) and crystalline Fe composite by in situ and ex situ annealing. The Fe/SiOC multilayer thin films were grown via magnetron sputtering with controlled length scales on a surface-oxidized Si (100) substrate. These Fe/SiOC multilayers were in situ or ex situ annealed at temperature of 600 °C or lower. The thin multilayer sample (~10 nm) was observed to have a layer breakdown after 600 °C annealing. Diffusion starts from low groove angle triple junctions in Fe layers. In contrast, the thick multilayer structure (~70 nm) was found to be stable and an intermixed layer (Fe_xSi_yO_z) was observed after 600 °C annealing. The thickness of the intermixed layer does not vary as annealing time goes up. The results suggest that the Fe_xSi_yO_z layer can impede further Fe, Si and O diffusion, and assists in maintaining morphological stability.

Keyword:

• thermal stability
• amorphous silicon oxycarbide
• nanocrystalline Fe
• multilayer

Acknowledgements

We acknowledge financial support from the DoE Office of Nuclear Energy, Nuclear Energy Enabling Technologies, award DE-NE0000533. The work was carried out in part in the Central Facilities of the Nebraska Center for Materials and Nanoscience, which is supported by the Nebraska Research Initiative.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the DoE Office of Nuclear Energy, Nuclear Energy Enabling Technologies, [grant number DE-NE0000533].