Using narrow nuclear reaction resonance profiling, aluminum profiles are obtained in ∼3.5 nm Al2O3 films deposited by low temperature (<400 °C) chemical vapor deposition on Si(100). Narrow and Auger depth show similar Al for thicker (∼18 nm) films. The profile the thin film is consistent with a silicate layer, consisting of Al–O–Si bond units, between silicon layer. Transmission electron microscopy shows evidence two-layer structure Si/Al2O3/Al stacks, x-ray photoelectron spectroscopy...

Magnetoelectric interactions as a function of applied electric field have been studied in ferrite-ferroelectric heterostructures at microwave frequencies. The measurements are performed on 1.5–2.0 μm thick nickel ferrite (NiFe2O4) films grown heteroepitaxially lead zinc niobate-lead titanate and magnesium substrates using direct liquid injection chemical vapor deposition. Large shifts the ferromagnetic resonance profile observed these due to strong magnetoelectric coupling resulting from...

Surface impurities involving parasitic reactions and gas evolution contribute to the degradation of high Ni content LiNixMnyCozO2 (NMC) cathode materials. The transient kinetic technique temporal analysis products (TAP), density functional theory, infrared spectroscopy have been used study formation surface on varying nickel NMC materials (NMC811, NMC622, NMC532, NMC433, NMC111) in presence CO2 H2O. reactivity a clean as characterized by conversion rate TAP reactor follows order: NMC811 >...

The adsorption and reaction of tetrakis(dimethylamido)hafnium (TDMAH) on hydrogen terminated Si(100) were studied by using in situ attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), transmission IR, quadrupole mass spectrometry (Q-MS). Surface gas phase reactions investigated at temperatures between 25 300 °C. Density functional theory (DFT) calculations benchmarked coupled cluster small models performed for decomposition via intramolecular insertion β-hydride...

Abstract Magnetoelectric heterostructures are being actively investigated for utilization in next generation microwave devices such as tunable filters and phase shifters. For efficient absorption magnetoelectric coupling, relatively thick (>1 µm) epitaxial spinel ferrite films with smooth topographies required the magnetic/ferroelectric heterostructures. Towards this goal, direct liquid injection (DLI)‐CVD has been utilized growth of nickel (NiFe 2 O 4 ) on MgAl (100) MgO substrates high...

Microstructural and ferromagnetic resonance properties of epitaxial nickel ferrite (NiFe2O4) films grown by direct liquid injection chemical vapor deposition are reported. While high-quality growth NiFe2O4 on (100)-oriented MgAl2O4 substrate is confirmed high resolution transmission electron microscopy, bright field (diffraction contrast) TEM studies reveal the presence dislocations also dark diffused contrast areas, which originate from antiphase domains. Angle frequency-dependent (FMR)...

Silicon nitride thin films, deposited by plasma enhanced chemical vapor deposition at temperatures between 250 and 50 °C from SiH4, N2 He, were characterized using transmission infrared spectroscopy, ellipsometry, wet etch rate, current-voltage analysis. At SiH4/N2/He flow ratios of 1/150/75, films with refractive index=1.80 H concentrations <20%, distributed equally in Si-H N-H units obtained. The concentration hydrogen its distribution bonds are sensitive to process temperature,...

Hafnium oxide dielectric thin films were deposited by metalorganic chemical vapor deposition with Hf (IV) t-butoxide and either an O2, N2, or N2O plasma in a 1:1 ratio helium. Films approximately 5nm thick analyzed using angle-resolved x-ray photoelectron spectroscopy (XPS) variable angle ellipsometry before after heat treatment ultrahigh vacuum up to 470°C. Interdiffusion and/or reaction of the film silicon substrate, as measured increase thickness Si-O type bonding at interface was most...

This article describes the kinetics of reactions that result in substrate consumption during formation ultrathin transition metal oxides on silicon. Yttrium silicate films (∼40 Å) with an equivalent silicon dioxide thickness ∼11 Å are demonstrated by physical vapor deposition (PVD) routes. Interface occur and postdeposition treatment observed compared for PVD chemical (CVD) yttrium CVD aluminum-oxide systems. Silicon diffusion, metal-silicon bond formation, involving hydroxides proposed as...

The surface chemistry of the hafnium-based atomic layer deposition precursor, tetrakis(ethylmethylamido) hafnium (TEMAH), on hydrogen-terminated Si(100) was studied for comparison with previously reported tetrakis(dimethylamido) (TDMAH) results by in situ attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and vacuo X-ray photoelectron (XPS). adsorption reaction experiments were investigated at substrate temperatures between 25 400 °C. Gas-phase products detected...

Hafnium oxide ultra thin films on Si are being developed to replace thermally grown SiO2 gates in complementary metal-oxide semiconductor devices. In this work, a specially designed attenuated total reflectance (ATR) Fourier transform infrared spectroscopy reaction cell has been observe adsorption of hafnium (IV) t-butoxide (HtB) onto (100), (111), and Ge ATR crystal heated temperatures between 60 250°C under 0.4torr vacuum allowing the observation initial pathways real time. Spectra...

In situ mass spectroscopy is used to sense plasma deposition of silicon and nitride, analyze gas phase reactant depletion, the efficiency silane conversion into thin film. A double-differentially pumped quadrupole spectrometer was monitor SiH4, Si2H6, H2 effluent from 100% SiH4 2% SiH4/He deposition, SiH4/He/N2 nitride processes. No significant changes in nitrogen related species were observed during deposition. However, Si show process dependence allowing reaction analysis. Disilane...

Abstract HfO 2 was deposited by chemical vapor deposition on Si, native SiO , and borosilicate glass surfaces using hafnium (IV) tert butoxide in a mesoscale flow reactor. Undulating thin film topographies were observed atomic force microscopy all substrates with peak‐to‐peak periods between 10 25 nm the presence of temperature gradient perpendicular to 25°C/mm. A computational fluid dynamic model suggests phenomenon originates from buoyancy driven roll type flow. The thickness uniformity...

CrO 2 films prepared by low pressure chemical vapor deposition (LPCVD) using Cr(CO)6 precursor have been investigated and compared with epitaxial half metallic CrO2 at atmospheric (APCVD) CrO3 for their magnetotransport surface magnetic properties. LPCVD showed higher resistivity than APCVD (100) on TiO2 substrates. Magnetoresistance of is comparable to that films. X-ray circular dichroism suggests a reduced moment This attributed antiferromagnetic alignment the uncompensated Cr spins in Cr2O3 layer.