Soft x-ray photoemission spectroscopy has been applied to determine the binding energy shifts and the valance band offset of HfO2 grown on Hf metal. Charging of oxide films upon x-ray exposure is found to be very severe and special care is taken to eliminate it. Photoemission results show the presence of metallic Hf ~from the substrate! with a 4 f 7/2 binding energy of 14.22 eV, fully oxidized ...

The paper discusses the design aspects of capacitive RF MEMS Symmetric Toggle Switch (STS) with particular emphasis on device compactness, reliability, and improvement in isolation & insertion loss by incorporating hafnium dioxide (HfO2) as a dielectric material. The major impact of the change from SiO2 to HfO2 having dielectric constant of 20, is the reduction in overall dimensions of the swit...

Atomic-scale understanding of HfO2 ferroelectricity is important to help address many challenges in developing reliable and high-performance ferroelectric (fe-HfO2) based devices. Though investigated from different angles, a factor that real device-relevant clearly deserves more attention has largely been overlooked by previous research, namely, the fe-HfO2/dielectric interface. Here, we invest...

Hafnium oxide (HfO2) high-k thin films have been deposited by radio frequency (rf) sputtering technique on p-type Si (100) substrate. The thickness, composition and phases of films in relation to annealing temperatures have been investigated by using cross sectional FE-SEM (Field Emission Scanning Electron Microscope) and grazing incidence x-ray diffraction (GI-XRD), respectively. GIXRD analysi...

We demonstrate that electron trapping at intrinsic precursor sites is endemic in non-glass-forming amorphous oxide films. The energy distributions of trapped electron states in ultra-pure prototype amorphous (a)-HfO2 insulator obtained from exhaustive photo-depopulation experiments demonstrate electron states in the energy range of 2-3 eV below the oxide conduction band. These energy distributi...

By combining capacitance–voltage measurements, TCAD simulations, and X-ray photoelectron spectroscopy, the impact of work function gate metals Ti, Mo, Pd, Ni on defects in bulk HfO2 at HfO2/InGaAs interfaces are studied. The oxidation Ti/HfO2 is found to create highest density interface border traps, while a stable Mo/HfO2 leads smallest traps our sample. extracted values Dit 1.27 × 1011 eV−1cm...

In his paper, Chandi C. Dey reports on the measurement of the nuclear quadrupole interaction of 181Hf(β−)181Ta in α-Hf metal with a few percent zirconium heated in air by perturbed angular correlation (PAC) of γ-rays. Since he did not observe the formation of HfO2 up to 773 K and during initial heating at 873 K for one day, he concluded that no oxygen is absorbed. The time dependent hyperfine i...

Monoclinic HfO2 nanoparticles (9 45 nm) are synthesized using a sol-gel method and optically characterized using transmissionand angle-dependent reflection spectroscopy in the midto far-infrared. A detailed HfO2 identification of the infrared-active phonon modes is presented; consistent with previously reported thin film values, and in excellent agreement with density functional perturbation th...

We have established in-line characterization techniques for analyzing the bulk and interface-charge properties of dielectric films, for process optimization. Surface charge analysis (SCA) is used to determine the densities of interface states, fixed charge, and near-interface traps in ultra-thin dielectrics, and is useful for tracking the influence of post-deposition processing on interface-cha...

Hafnium dioxide films have been produced by plasma ion assisted electron beam evaporation, utilizing argon or xenon as working gases. The optical constants of the layers have been investigated by spectrophotometry, while X-ray reflection measurements (XRR), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) have been performed with selected samples. The corre...