β   Fe2 O 3: Preparation of Thin Films by Chemical Vapor Deposition from Organometallic Chelates and Their Characterization

Abstract

Thin films of a new iron oxide phase, β‐Fe2O3 , were prepared by chemical vapor deposition (CVD) from tris(trifluoroacetylacetonato) iron (III) at 300°C in the presence of oxygen onto a variety of substrates. The films were characterized by x‐ray diffraction analysis, scanning electron microscopy, and Mössbauer spectroscopy. For the latter measurements the films were prepared from enriched 57Fe2O3 . The ultraviolet, visible, and infrared spectra of the films were also recorded. The iron (III) oxide phase prepared was bcc having the bixbyite structure, Ia3 space group and the lattice constant a0=9.393Å . There are 16 formula molecules to the unit cell and the two iron atoms occupy two nonequivalent distorted octahedral lattice sites: 3̅ (8b); 2(24d).

Magnetic properties of bulk Fe-doped indium oxide

“…From this picture, it seems that the solubility limit for Fe 3+ in In 2 O 3 depends on the sintering atmosphere, with a solubility limit as high as 27% for samples sintered under air. The same solubility limit has been reported previously by Ben-Dor et al [21]. As Fe 2+ does not substitute for In 3+ [7] and β-Fe 2 O 3 [21].…”

“…The same solubility limit has been reported previously by Ben-Dor et al [21]. As Fe 2+ does not substitute for In 3+ [7] and β-Fe 2 O 3 [21].…”

“…The inset of figure 1 shows the evolution of the lattice parameter with the nominal iron fraction in In 2−x Fe x O 3 , for samples sintered under air or argon. The solid line represents Vegard's law between a = 10.117Å for In 2 O 3 [7] and a = 9.393Å for β-Fe 2 O 3 [21]. This Vegard's law is well followed until x = 0.3 for samples sintered under argon and x = 0.5 for samples sintered under air.…”

Low Temperature MoCVD Routes to Thin Films from Transition Metal Precursors

“…These precursors have been employed to deposit oxide films of elements such as Zr, Hf, Fe, Ni, and Cu at temperatures as low as 450°C [133][134][135][136][137][138][139]. The number of published reports that describe the use of acac compounds for the deposition of metal oxides has increased tremendously in the last few years; most of these publications involve the use of acac complexes as sources for the deposition of high temperature superconductors.…”

Solid State Reactions in the Cr‐Si‐C System

“…SEM and EDX confirm the multiphase composition and are in a good agreement with the powder XRD results. The proposed ternary compound of Cr 5Ϫx Si 3Ϫz C xϩz is isostructural with Mo 4,8 Si 3 C 0.6 (Nowotny's-type phase) [2,3] and crystallizes in the hexagonal structure (Mn 5 Si 3 -type; space group P6 3 /mcm) with a ϭ 698.353(8) pm and c ϭ 474.259(8) pm. Sintered products at higher temperatures (1600 and 1800°C) exhibit not only the ternary and binary carbide phases but also α-SiC (6H-SiC-and 4H-SiC).…”