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...

Abstract A theoretical and experimental study is presented of dislocation nucleation processes in the initial stages coherency breakdown GeSi/Si(100) strained layers. It shown that use core parameters appropriate to semiconductors leads far higher predictions than previous studies for activation energy half-loop nucleation. Homogeneous thus unlikely at low misfit absence stress concentrations large surface steps. Experimentally actual GeSi epilayers (less 1%) are deduced from microstructure...

Abstract In order to characterize more completely defect structures typical of high dose neutron irradiation experiments, the determination perfect dislocation loop geometry, as defined by direction and sese Burgers vector b plane normal n, has been re-examined. The practical aspects electron diffraction contrast experiments leading definitions these vectors have considered. It shown that nature a relatively proportion loops which constitute structure studied in Part II can confidently be...

Transmission electron microscopy has been used to characterize the crystallography of structural defects observed in a Czochralski-grown silicon crystal after two-step annealing treatment. The defect population is complex and consists precipitates, perfect-dislocation loops, single double stacking-fault microprecipitate colonies on stacking faults, imperfect/perfect dislocation-loop pairs. Extensive diffraction-contrast experiments have carried out order evaluate nature these defects....

Abstract 4D printing combines advancements in 3D with smart materials that change properties response to external stimuli, enabling the fabrication of functional devices directly from printer. Microscale is rapidly growing, driving discovery and applications new strategies. The interest microscale comes its potential propel industrial transformation across different sectors, ranging advanced healthcare cryptography. However, this requires rational design a good understanding material...

Abstract An electron microscope study has been made of the time-dependent annealing behaviour interstitial loops in impure and pure molybdenum neutron-irradiated at 77°K (A77 C77) respectively vacancy 473°K (C473). The results have quantitatively analysed loop growth compared with that predicted theoretically for perfect growing by bulk vacancy-limited diffusion mechanism a glide self-climb mechanism. It shown observed A77 C77 is accounted On other hand, C473 can be although it considered...

Since its introduction in the 1980s, 3D printing has advanced as a versatile and reliable tool with applications different fields. Among available techniques, two-photon polymerization is regarded one of most promising technologies for microscale due to ability combine high fidelity down submicron scale free-form structure design. Recently, technology been enhanced through implementation faster laser scanning strategies, well development new photoresists. This paves way wide range...

We report the fabrication, chemical, optical, and photoluminescence characterization of amorphous silicon-rich oxynitride (SiOxNy:H) thin films by plasma-enhanced chemical-vapor deposition. The film compositions were followed changes in refractive index. X-ray photoelectron Fourier transform infrared spectroscopy indicate that chemical composition is dominated silicon suboxide bonding with N present as a significant impurity. A broad tunable (PL) emission visible at room temperature quantum...

Abstract Molybdenum, ranging in resistivity ratio (ρ293°K/ρ4·2°K) from 150 to 8000, has been neutron irradiated at 77°K and 473°K integrated fission doses of ∼1020 n. cm−2 ∼7 × 1019 cm−2, respectively. A detailed electron microscope study made the damage structures both before after a post-irradiation anneal one hour 1173°K. It is found that defect cluster topology specimens sensitive function material purity irradiation temperature. model discussed specifically explain interstitial clusters...

Abstract Experimental electron microscope images of dislocation loops in molybdenum have been compared to theoretical loop displayed the form computer simulated micrographs. The exact displacement field around a circular edge has calculated using isotropic elasticity theory; this together with two‐beam dynamical theory diffraction contrast used compute image intensities. Specific results are given for radius ≈ 250 Å and 25 Å. Their studied over narrow range numerous variables which known...

Abstract Square cross-sectional holes with widths of about 1 nm can be formed in MgO crystals using circular cross-section high-current-density electron probes which are focused and oriented close to <001>. High-resolution scanning transmission microscopy has been used reveal, on a unit cell scale, the three-dimensional geometry hole structures as they grow. The develop from exit face crystal, have profile is clearly related that probe, generated incident energies low 40keV. Unlike other...

Abstract A new transmission electron microscopy technique is described, convergent-beam imaging (CBIM), in which an image formed using a convergent beam focused above or below thin crystalline specimen. Superimposed on the are higher-order Laue zone (HOLZ) lines, displacements of map spatial variation strains, lattice parameters and crystallographic rotations. The has its normal resolution, superimposed diffraction information angular resolution about 10−4 rad, this comes from regions...

Soumerai, Stephen B. ScD; Avorn, Jerry MD; Taylor, William C. Wessels, Michael Maher, Donna RN; Hawley, Sharon L. BA Author Information

A new dislocation source has been observed for the first time in ${\mathrm{Ge}}_{x}{\mathrm{Si}}_{1\ensuremath{-}x}/\mathrm{Si}$ strained epitaxial layers. Transmission electron microscopy reveals that strain relaxation at "critical thickness" low-mismatch Ge-Si alloys can occur through emission of glissile dislocations from $\frac{1}{6}〈114〉$ stacking faults. novel mechanism is proposed to explain observations whereby boundary a fault dissociates (in one two ways) emit $\frac{1}{2}〈110〉$...

An optical and electron microscopy study of the nucleation growth stacking faults in {001}-oriented epitaxial silicon has been carried out following pretreatment crystal hydrofluoric acid thermal oxidation steam at 1050°C. A direct correlation etched surface structure as revealed by interference contrast scanning with substructural defects transmission established for times ≥1 min. The observations are divided into five stages which, taking TEM a reference, (i) formation needle-shaped...

Abstract Transmission electron microscopy has been used to investigate point defect aggregates which were resolvable as dislocation loops in neutron irradiated and annealed molybdenum. The so-called formal analysis was employed determining the direction sense of their Burgers vectors. In foils containing a wide spectrum loop sizes, both vacancy interstitial type have identified with Burges vectors a/2⟨111⟩.

Doping-dependent contrast in secondary electron images of p/n junctions silicon obtained a field-emission scanning microscope was observed and characterized. The optimum experimental conditions for observing this ‘‘electronic’’ were established by investigating the effect material parameters on magnitude contrast. between bright p-type areas darker n-type maximized at an accelerating voltage ∼1 kV, when through-the-lens detector configuration employed. Secondary profiles boron doped p+/n...