Effects of impurities on the interface of ion beam sputtered tungsten with silicon

• Published in: Applied surface science Vol. 53; pp. 82 - 86
• Main Authors: Meyer, Françoise, Bouchier, Daniel, Benhocine, Abdelhamid, Gautherin, Guy
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.11.1991; Elsevier Science
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Metals. Metallurgy; Physics; Solid surfaces and solid-solid interfaces; Surface structure and topography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/0169-4332(91)90246-G

In this study, we have investigated the properties of the interface of ion-beam-sputter-deposited-W (IBSD-W) with silicon modified by the presence of an interfacial contamination (oxygen, nitrogen or boron). Auger electron spectroscopy combined with depth profiling was used to investigate the growth mode of IBSD-W onto Si as well as the redistribution of elements during in-situ thermal annealing. The growth mode is strongly affected by the incident ion energy and the presence of an interfacial oxide. We found that a thin oxide layer (≈ 2 ML) is not an efficient barrier to prevent silicon diffusion toward the metal surface. A thicker oxide (≈ 6 ML) greatly limits the silicon diffusion and inhibits silicide formation up to 700°C. Finally, the deposition of WN films by reactive ion beam sputtering leads to the nitridation of the silicon substrate and a stable contact up to 700°C.