CVD of Lanthanum Oxyfluoride-Based Thin Films from a Lanthanum β-Diketonate Diglyme Precursor

Abstract

Lanthanum oxyfluoride-based thin films were grown on SiO 2 and Si(100) by CVD from La(hfa) 3´d iglyme (Hhfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione; diglyme = bis(2-metoxyethyl)ether), acting as the source for both lanthanum and fluorine. Film syntheses were performed in an atmosphere of nitrogen + wet oxygen, with particular attention paid to the structural and compositional evolution as a function of the deposition temperature (200±500 C). To this aim, specimens were subjected to a multi-technique characterization by means of glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), and atomic force microscopy (AFM). The formation of nanophasic (crystallite size < 30 nm) films containing LaOF, with a cleaner precursor conversion at the highest deposition temperatures, is evidenced and discussed, highlighting the most critical parameters for obtaining lanthanum oxyfluoride coatings with controlled properties.

Lanthanum Oxyfluoride Sol−gel Thin Films by a Simple Single-Source Precursor Route

“…[31][32][33][34] However, on raising the annealing temperature to that corresponding to a progressive decrease of the fluorine content, severe modifications were observed in the band shape. The 3d satellite structure of the samples annealed at 300°C closely resembles that of the LaF 3 one; i.e., each of the 3d 5/2 (BE ) 837.1 eV) and 3d 3/2 (BE ) 854.1 eV) signals 8 shows a relatively weak satellite on the high binding energy side. 35 On increasing the annealing temperature and then the oxygen amount, the satellite peaks gain intensity due to a more efficient O 2p f RE 4f charge transfer with respect to the F 2p f RE 4f one.…”

The Potential of Supported Cu2O and CuO Nanosystems in Photocatalytic H2 Production

“…[18] The custom-built CVD reaction system used for copper oxide depositions [19,20] consisted of a horizontal quartz tube cold-wall reactor equipped with a resistively heated susceptor and an external glass vessel for precursor vaporization. Depositions were carried out in O 2 -based reaction atmospheres at growth temperatures between 350 and 550 8C on ptype SiA C H T U N G T R E N N U N G (100) wafers (MEMC, Merano, Italy; size: 1 cm 1 cm 1 mm), preliminarily subjected to etching treatment in 2 % aqueous HF to remove the native SiO 2 layer from their surface.…”

Temperature‐Controlled Synthesis and Photocatalytic Performance of ZnO Nanoplatelets

“…While in the former case oxygen was used both as a reactant and carrier gas [U(O 2 ) = 40 sccm], in the latter the precursor vapors were transported in flowing N 2 [U(N 2 ) = 40 sccm], and an O 2 flow was introduced separately into the reaction chamber after passing through a water reservoir kept at 50°C [U(O 2 ) = 40 sccm]. Under these conditions, the H 2 O partial pressure was estimated to be ≈1.5 mbar [41]. In all cases, the gas lines connecting the water and precursor reservoirs to the reaction chamber were heated to 110°C to avoid undesired condensation phenomena.…”

“…ZnO Nanosystem Synthesis: The cold-wall, low-pressure CVD apparatus used to grow the nanoplatelets has already been described in previous works [40,41]. The precursor compound was placed in an external vessel and vaporized at 60°C throughout each deposition run.…”