Influence of deposition parameters on the texture of chemical vapor deposited tungsten films by a WF6/H2/Ar gas source

Article abstract of DOI:10.1149/1.1838791

In order to investigate the relationship between the film texture and the deposition parameters including gas composition, temperatures, and substrate materials, polycrystalline tungsten films were prepared by reduction of tungsten hexafluoride with hydrogen. The experimental results show that the orientations of the textured films correlate closely with WF₆ concentrations in the gas mixture and deposition temperatures. High WF₆ concentrations enhance the formation of the 〈100〉 textured films, while low WF₆ concentrations facilitate the formation of the 〈111〉 textured films. The 〈111〉 texture, usually observed in tungsten films deposited at high temperatures (≥400 °C) and high ratios of H₂ to WF₆, can also form at low deposition temperatures (370 °C) when the WF₆ concentration used is low enough (0.6 vol %). The WF₆ concentration for obtaining a 〈100〉 textured film increases with increasing deposition temperatures. On the other hand, the concentrations of hydrogen gas have minimal influence on the formation of the film textures. Therefore, in terms of gas composition, the WF₆ concentration, not the ratio of H₂ to WF₆, is a compact factor which directly dominates the texture of the films. The effect of substrate on the film texture was only found in the initial growth stage. The crystals formed at the beginning of the film growth were randomly oriented. A preferential orientation became pronounced with increasing film thickness through the competitive crystal growth.

Full text of DOI:10.1149/1.1838791

Downloaded on 2015-06-08 to IP 132.239.1.230 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-06-08 to IP 132.239.1.230 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-06-08 to IP 132.239.1.230 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-06-08 to IP 132.239.1.230 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-06-08 to IP 132.239.1.230 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-06-08 to IP 132.239.1.230 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).