Preparation of WSI2 by rapid thermal annealing of CVD thin films of tungsten

✍ Scribed by KA Gesheva; DS Gogova; GD Beshkov; V Popov

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 431 KB
• Volume: 51
• Category: Article
• ISSN: 0042-207X
• DOI: 10.1016/s0042-207x(98)00155-9

✦ Synopsis

Tungsten silicide (WSi i ) films were prepared by rapid thermal annealing (RTA) of W films obtained by chemical vapor deposition (CVD) from carbonyl precursor-W(CO) 6 . The RTA process proceeds at 800-1400°C in different gas environments-argon, nitrogen, vacuum, etc. Investigations of the crystal phase structure were performed by Reflection High Energy Electron Diffraction (RHEED) method. Difference in the phase composition was observed for ''thin'' and ''thick'' WSi 2 . Close to the surface of W films, a pure metal rich phase is formed, and at the interface W/Si, a phase rich of Si is found. Diffusion was considered to be the controlling process in the kinetics formation of WSi 2 . The influence of the gas environment on WSi 2 was also studied. The comparison made shows that nitrogen favours WSi 2 formation. Some of the samples have shown a certain degree of texturing.