Titanium arsenide films from the atmospheric pressure chemical vapour deposition of tetrakisdimethylamidotitanium and tert-butylarsine

Abstract

Thin films of titanium arsenide have been deposited from the atmospheric pressure chemical vapour deposition (APCVD) of [Ti(NMe(2))(4)] and (t)BuAsH(2) at substrate temperatures between 350-550 °C. Highly reflective, silver coloured films were obtained which showed borderline metallic-semiconductor resistivities. The titanium arsenide films were analyzed by scanning electron microscopy (SEM), Raman spectroscopy, wavelength dispersive analysis of X-rays (WDX), powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The films showed variable titanium to arsenic ratios but at substrate temperatures of 500 and 550 °C films with a 1 : 1 ratio of Ti : As, consistent with the composition TiAs, were deposited. Powder XRD showed that all of the films were crystalline and consistent with the formation of TiAs. Both nitrogen and carbon contamination of the films were negligible.

Titanium, zirconium, hafnium

“…63 CVD methods have been used to make titanium arsenide thin films from [Ti(NMe 2 ) 4 ] and t BuAsH 2 . 64 [Zr(NMe 2 ) 4 ] reacts with two 1,2-cyclopentyl-bridged diiminophosphine proligands (NPN) forming two five coordinate bis(dimethylamido) complexes. On reduction, one of these forms a dinuclear zirconium-dinitrogen complex, with a side-on bridging dinitrogen ligand.…”

Highly efficient NIR to visible upconversion in a ZnO:Er,Yb thin film deposited by a AACVD atmospheric pressure process

“…15 Doping high refractive index materials with RE ions is one of the most promising approaches, which has not been investigated yet. 17,22,23 On the other hand, it is well known that the local symmetry restriction around rare earth ions leads to a relative weak UC emitted from a material doped only with Er 3+ . 16 Compared with other optical materials, ZnO has superior qualities such as high refractive index 17 (~2) and excellent physical and chemical stability.…”

“…21 Aerosol-assisted chemical vapor deposition (AACVD) at atmospheric pressure process presents some key advantages, including a mass production with large area, a wider choice and availability of precursors, high CVD quality products and stoichiometric control of the dopants. 17,22,23 On the other hand, it is well known that the local symmetry restriction around rare earth ions leads to a relative weak UC emitted from a material doped only with Er 3+ . Fortunately, UC emission intensities can be enhanced when Yb 3+ ions are codoped with Er 3+ .…”