Luminescent YbVO4 by atomic layer deposition.

UV to visible and near-infrared converting thin films of YbVO4 have been deposited by atomic layer deposition, using the precursor combinations Yb(thd)3 (thd = 2,2,6,6-tetramethyl-3,5-heptanedione) and O3, and VO(thd)2 and O3 at a deposition temperature of 240 °C, followed by post deposition annealing at 400-1000 °C. The UV absorption and the visible and near-infrared emission have been investigated in detail. The structure, thickness and composition of the deposited films have been studied by X-ray diffraction, ellipsometry, and X-ray fluorescence, respectively. The optimal pulse ratio of Yb(thd)3 and VO(thd)2 with respect to near-infrared emission was found to be 1 : 3, which also yielded the most crystalline sample after annealing. Crystallization of the films is accelerated when an excess of V2O5 is present, enabling crystallization at temperatures as low as 500 °C, probably through a flux aided process.

(E)-1-(2-Iodo-phen-yl)-2-phenyl-diazene.

The mol-ecule of the title compound, C(12)H(9)IN(2), is approximately planar [maximum deviation = 0.020 (5) Å] with a trans arrangement of the groups around the N=N double bond. This double bond is rotated away from the iodine substiuent.