Trimethylboron as Single-Source Precursor for Boron-Carbon Thin Film Synthesis by Plasma Chemical Vapor Deposition
2016 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 120, no 38, 21990-21997 p.Article in journal (Refereed) Published
Boron–carbon (BxC) thin films are potential neutron converting layers for 10B-based neutron detectors. However, as common material choices for such detectors do not tolerate temperatures above 500 °C, a low temperature deposition route is required. Here, we study trimethylboron B(CH3)3 (TMB) as a single-source precursor for the deposition of BxC thin films by plasma CVD using Ar plasma. The effect of plasma power, TMB/Ar flow ratio and total pressure, on the film composition, morphology, chemical bonding, and microstructures are investigated. Dense and boron-rich films (B/C = 1.9) are achieved at high TMB flow under a low total pressure and high plasma power, which rendered an approximate substrate temperature of ∼300 °C. Films mainly contain B–C bonds with the presence of B–O and C–C, which is attributed to be the origin of formed amorphous carbon in the films. The high H content (15 ± 5 at. %) is almost independent of deposition parameters and contributed to lower the film density (2.16 g/cm3). The plasma compositional analysis shows that the TMB molecule decomposes to mainly atomic H, C2, BH, and CH. A plasma chemical model for the decomposition of TMB with BH and CH as the plausible film depositing species in the plasma is proposed.
Place, publisher, year, edition, pages
American Chemical Society (ACS), 2016. Vol. 120, no 38, 21990-21997 p.
IdentifiersURN: urn:nbn:se:liu:diva-132478DOI: 10.1021/acs.jpcc.6b06529ISI: 000384626800097OAI: oai:DiVA.org:liu-132478DiVA: diva2:1046268
Funding Agencies|European Spallation Source ERIC; Knut and Alice Wallenberg Foundation; BrightnESS project (Horizon) ; Carl Tryggers Foundation for Scientific Research [CTS 14:431]2016-11-132016-11-122016-12-05Bibliographically approved