Large vacancy clusters, or voids, formed during crystal growth have been reported in Ge. The divacancy is a precursor to such clusters, and is believed to be stable up to 150 or 180 °C. It is also believed to form in Ge irradiated at room temperature where single vacancies are mobile. Density... (Read more)

A computationally efficient hybrid Green's function (GF) technique is developed for multiscale modeling of point defects in a trilayer lattice system that links seamlessly the length scales from lattice (subnanometers) to continuum (bulk). The model accounts for the discrete structure of the lattice... (Read more)

We carry out a comprehensive density-functional study of the vacancy-oxygen (VO) center in germanium using large H-terminated Ge clusters. The importance of a nonlinear core correction to account for the involvement of the 3d electrons in Ge-O bonds is discussed. We calculate the electrical... (Read more)

Using ab initio total energy density-functional theory calculations, we investigated the electronic, structural, and magnetic properties of manganese-doped germanium nanowires. The nanowires have been constructed along the [110] direction and the dangling bonds on the surface have been... (Read more)

We investigate, through ab initio density-functional theory calculations, the electronic and structural properties of neutral Mn impurities at tetrahedral interstitial and substitutional sites in both Si and Ge layers of a Si/Ge heterostructure. We conclude that substitutional Mn at the Ge... (Read more)

The role of hydrogen in the exfoliation of Ge is studied using cross-sectional transmission electron microscopy, atomic force microscopy, and multiple-internal transmission mode Fourier-transform infrared absorption spectroscopy and compared with the mechanism in silicon. A qualitative model for the... (Read more)

We report an ab initio study of the electronic properties of surface dangling-bond (SDB) states in hydrogen-terminated Si and Ge nanowires with diameters between 1 and 2 nm, Ge/Si nanowire heterostructures, and Si and Ge (111) surfaces. We find that the charge transition levels ε(+/-)... (Read more)

The Schottky barrier height in metal/Ge contacts shows weak dependence on the metal work function indicating strong Fermi-level pinning close to the Bardeen limit. The pinning factor S is about 0.05 and the charge neutrality level (CNL) is only about 0.09 eV above the top of the valence... (Read more)

Defect formation during Pd and Pt germanidation of n-type germanium, using rapid thermal annealing in the range of 300–500 °C, is investigated by deep level transient spectroscopy. Small concentrations of an electron trap at ~E_C−0.385 eV are found,... (Read more)

The authors have employed deep level transient spectroscopy to investigate the defects introduced in n-type Ge during 160 keV indium (In) ion implantation. Our results show that In implantation introduces three prominent electron traps with energy levels at... (Read more)

Channeling implantation of Ga into Ge is performed at two very different ion fluxes (10¹² and 10¹⁹ cm^–2 s^–1), at two temperatures (room temperature and 250 °C), and at five different fluences. The fluence dependence of the range profiles... (Read more)

We have investigated by deep level transient spectroscopy the hole and electron trap defects introduced in n-type Ge during electron beam deposition (EBD) of Pd Schottky contacts. We have also compared the properties of these defects with those introduced in the same material during... (Read more)

Nickel-germanide Schottky barriers have been made on n-type germanium and evaluated by deep level transient spectroscopy in order to detect possible metal indiffusion during the 30 s rapid thermal annealing (RTA) employed for the germanidation. It is shown that while no electron traps have... (Read more)

We present an ab initio density functional study on the electronic structure and electrical properties of divacancies in Ge. Although suffering essentially different Jahn-Teller distortions when compared to the analogous defect in Si, the relative location of the electrical levels in the gap... (Read more)

We report experimental study of spin transport in nanowire spin valve structures consisting of three layers—cobalt, germanium, and nickel. The spin diffusion length in the Ge is estimated to be about 400 nm at 1.9 K and the corresponding spin relaxation time is about 4 ns. At 100 K, the... (Read more)

The intensities of infrared absorption due to the asymmetric stretching vibrations of interstitial oxygen atoms in Ge crystals enriched with ¹⁶O and ¹⁸O isotopes have been compared with oxygen concentrations determined by means of secondary ion mass spectrometry. For Ge samples... (Read more)

We report on a first-principles investigation of the structural and vibrational properties of vitreous germania (v-GeO₂). Our work focuses on a periodic model structure of 168 atoms, but three smaller models are also studied for comparison. We first carry out a detailed structural... (Read more)

We present a comprehensive spin-density functional modeling study of the structural and electronic properties of donor-vacancy complexes (PV, AsV, SbV, and BiV) in Ge crystals. Special attention is paid to spurious results which are related to the choice of the boundary... (Read more)

The solubilities of substitutional and interstitial copper (Cu^s and Cuⁱ) have been measured in intrinsic and extrinsic n- and p-type Ge, Si, and GaAs, using Cu⁶⁴. These measurements show that Cu^s is a triple acceptor in... (Read more)

At liquid helium temperatures, spin resonance of localized donor electrons has been observed in phorphorus-, arsenic-, and bismuth-doped germanium. The presence of hyperfine splitting confirms the singlet as the ground state for all three. The separation of the excited triplet states has been... (Read more)

A theory of paramagnetic resonance on acceptor centres in deformed and non-deformed Ge and Si type crystals is developed. The splitting of the ground state under the action of the deformation and magnetic field is determined and the probability of transitions between levels is estimated. Using the... (Read more)

I. Introduction (p.258): II. Emprical Properties (p.261): 1. Energy Levels (p.261), a. Ionization Energies, b. Spectra of Excited States, 2. Spin Resonance (p.266), a. Electron Spin Resonance, b. Double Resonance, 3. Static Magnetic Susceptibility (p.271), III. Structure of Donor States (p.271): 4. Conduction Bands of Silicon and Germanium (p.271), a. Silicon, b. Germanium, 5. Effective Mass Theory of Donor States (p.274), a. Single Band Minimum at k=0, b. Several Conduction Band Minima, c. Matrix Elements for Radiative Transitions, 6. Numerical Results and Comparison with Experiments (p.285), a. Energy Levels, b. Wave Functions, 7. Corrections to the Effective Mass Formalism (p.289), a. General Considerations, b. Corrected Wave Functions, c. Comparison with Experiment, IV. Structure of Acceptor States (p.297): 8. Valence Bands of Silicon and Germanium (p.297), a. Silicon, b. Germanium, 9. Effective Mass Equations for Acceptor States (p.300), 10. Approximate Solutions and Comparison with Experiment (p.301) a. Germanium b. Silicon V.Effects of Strains and of Static Electric and Magnetic Fields (p.306): 11. Strains (p.306) a. Donor States, b. Acceptor States, 12. Stark Effect (p.311)