HW-CVD is largely used for device-quality silicon-related applications, mainly photovoltaic devices, for research and industrial applications. In HW-CVD, the source gases are decomposed on a hot wire placed at some distance in front of the substrate, which leads to film deposition from highly active species. Typically, high wire temperatures are used (1700-2000 °C, with a tungsten, tantalum, or iridium filament) to obtain complete decomposition of metal-organic precursors and evacuation of the formed radicals from the hot wire towards the substrate. However, depending on the material deposited and the precursors used, such a high wire temperature may not be required. Other applications of HW-CVD technique have appeared in recent years, including the deposition of metallic copper and the growth of some oxides (e.g., TiO₂ and SnO₂).

We modified HW-CVD method and applied it to deposit Ge₂S₂Te₅ and GeTe layers at a wire temperature of ˜600 °C. Recently, our modified HW-CVD method was used for the growth of In₂O₃-ZnO layers, and for the growth of doped ZnO and Ga₂O₃ layers, at a wire temperature of <1000 °C. 

Main modifications of HW-CVD:

• HW-CWD principles were combined with the principles of Pulsed-Injection MOCVD. This allows a better control of precursors dosing into reactor and better control of vapor phase composition, film growth rate and film thickness.
• Tungsten, tantalum or iridium filaments were changed by nickel, nichrome or other alloys filaments, more stable in an oxygen containing atmosphere which are necessary for oxide deposition.

Abrutis A., Plausinaitiene V., Skapas M., Wiemer C., Salicio O., Pirovano, A., Varesi E., Rushworth S., Gawelda W., Siegel J. Hot-wire chemical vapor deposition of chalcogenide materials for phase change memory applications. Chemistry of Materials 20 (2008) 3557-3559.

A. Abrutis, V. Plausinaitiene, M. Skapas, C. Wiemer, W. Gawelda, J. Siegel, S. Rushworth. Hot-wire chemical vapor growth and characterization of crystalline GeTe films. Journal Crystal Growth, 311 (2009) 362-36

W. Gawelda, J. Siegel, C.N. Afonso, V. Plausinaitiene, A. Abrutis, C. Wiemer. Dynamics of laser-induced phase switching in GeTe films.Journal of Applied Physics, 109 (2011), Art. No 123102

R. Fallica, F. Volpe, M. Longo, C. Wiemer, O. Salicio, A. Abrutis. Electronic properties of crystalline Ge_1-xSb_xTe_y thin films. Applied Physics Letters, 101 (2012) Art. No 102105.

A.Abrutis, L. Silimavicus, V. Kubilius, T. Murauskas, Z. Saltyte, S. Kuprenaite, V. Plausinaitiene. On the possibility to grow zinc oxide-based transparent conducting oxide films by hot-wire chemical vapor deposition. Journal of Vacuum Science & Technology A, 32 (2014)  020602

A. Abrutis, L. Silimavicius, V. Kubilius, T. Murauskas, Z. Saltyte, V. Plausinaitiene, Doped zinc oxide films grown by hot-wire chemical vapour deposition. Thin Solid Films, 576 (2015) 88-97.