In-situ synthesis of the anhydrous La(hfac)(3) precursor: A viable route to the MOCVD of LaF3

The anhydrous La(hfac)(3) precursor was obtained in situ by a vapor-solid r eaction between hexafluoroacetylactonate (Hhfac) and La2O3 powder in the so urce reservoir of a metal-organic chemical vapor deposition (MOCVD) reactor . Fourier transform infrared spectroscopy (FTIR) in-situ measurements were used to identify the nature of the precursor in the gas phase. Clean LaF3 f ilms (60-260 nm thick) were deposited on SiO2/Si substrates in both Ar and Ar/O-2 environments. They were characterized by grazing incidence X-ray dif fraction, (GIXRD), X-ray photoelectron spectroscopy (XPS) depth profiles, s canning electron microscopy (SEM), and energy dispersive X-ray (EDX) analys is. Very thin (< 15 nm) films were also deposited in order to investigate the n ucleation and growth processes. Deposited films were found to consist of is lands grown on the silicon substrate. The surface coverage depends on the s ublimation and substrate temperatures, as well as on the nature of the carr ier/reacting gas.