HfO₂ films were grown by atomic layer deposition using two different precursor chemistries—HfCl₄ and tetrakis(diethylamido)hafnium (TDEAH) with H₂O as the oxidant. Electrical measurements on capacitor structures fabricated using the films showed a 0.4 V... (Read more)

Light-emitting centers in alkali-ion-implanted quartz have been investigated with respect to the solid phase epitaxial growth of the ion irradiation induced amorphous zone. Cathodoluminescence was studied under the conditions of chemical epitaxy in annealing the samples, implanted with... (Read more)

4H-SiC single crystalline substrates were implanted at room temperature with 150 keV Al⁺ ions using fluences of 4×10¹⁴, 1×10¹⁵, and 2×10¹⁵ cm⁻² with current density of 2.5 µA cm⁻².... (Read more)

Temperature dependent Hall effect (TDH), low temperature photoluminescence (LTPL), secondary ion mass spectrometry (SIMS), optical admittance spectroscopy (OAS), and thermally stimulated current (TSC) measurements have been made on 6H-SiC grown by the physical vapor transport technique... (Read more)

In He implantation induced cavities highly contaminated with metals (Au, Ni, Pt) we found that, when no three-dimensional structure is observed, the shape of the cavities can be strongly modified depending on the nature of the metal and on its trapped quantity. The equilibrium shape of cavities is... (Read more)

We report on metal-organic chemical vapour deposition growth of GaN:Fe and its characterization by means of high-resolution X-ray diffraction, secondary ion mass spectroscopy, electron spin resonance, and magnetization measurements. Electron spin resonance studies demonstrate the existence of Fe in... (Read more)

The transient enhanced diffusion of acceptor impurities severely affects the realization of ultrahigh doping regions in miniaturized Si-based devices. Fluorine codoping has been found to suppress this transient diffusion, but the mechanism underlying this effect is not understood. It has been proposed that fluorine-impurity or fluorine–native-defect interactions may be responsible. Here we clarify this mechanism combining first-principles theoretical studies of fluorine in Si and purposely designed experiments on Si structures containing boron and fluorine. The central interaction mechanism is the preferential binding of fluorine to Si-vacancy dangling bonds and the consequent formation of vacancy-fluorine complexes. The latter effectively act as traps for the excess self-interstitials that would normally cause boron transient enhanced diffusion. Instead, fluorine-boron interactions are marginal and do not play any significant role. Our results are also consistent with other observations such as native-defect trapping and bubble formation. (Read more)

The influence of nitrogen concentration at a nitrided oxide/silicon interface on the activation energies of both near-interface fixed-charge trapping and interface state generation caused by negative bias temperature instability stress has been studied quantitatively. It is observed that the charge... (Read more)

The effect of vacancies on the behavior of F in crystalline Si has been elucidated experimentally for the first time. With positron annihilation spectroscopy and secondary ion mass spectroscopy, we find that F retards recombination between vacancies (V) and interstitials (I) because V and I trap F to form complexes. F diffuses in the V-rich region via a vacancy mechanism with an activation energy of 2.12±0.08 eV. After a long annealing time at 700ºC, F precipitates have been observed by cross-section transmission electron microscopy which are developed from the V-type defects around the implantation range and the I-type defects at the end of range. (Read more)

Recent results from studies of shallow donors, pseudodonors, and deep level defects in SiC are presented. The selection rules for transitions between the electronic levels of shallow donors in 4H–SiC in the dipole approximation are derived and the ionization energy for the N donor at... (Read more)

On annealing a boron implanted Si sample at ~800 °C, boron in the tail of the implanted profile diffuses very fast, faster than the normal thermal diffusion by a factor 100 or more. After annealing for a sufficiently long time, the enhanced diffusion saturates. The enhanced diffusion is... (Read more)

Electron paramagnetic resonance (EPR) and optically detected magnetic resonance (ODMR) experiments have been performed on a set of GaN epitaxial layers doped with Mg from 2.5?10¹⁸ to 5.0?10¹⁹ cm^-3. The samples were also characterized by secondary-ion-mass... (Read more)

It is important to understand the distribution of recoil-implanted atoms and the impact on device performance when ion implantation is performed at a high dose through surface materials into single crystalline silicon. For example, in ultralarge scale integration impurity ions are often implanted... (Read more)

Photosensitive electron paramagnetic resonance (EPR) investigations of unintentionally doped, semi-insulating (s.i.) 4H?SiC have been made at 37 GHz and 77 K including photoexcitation and photoquenching experiments. In the dark the EPR spectrum consists of a low intensity line due to boron on the... (Read more)

Experimental studies of size-related effects in silicon nanocrystals are reported. We present investigations carried out on nanocrystals prepared from single-crystal Si:P wafer by ball milling. The average final grain dimension varied depending on the way of preparation in the range between 70 and... (Read more)

The effects of hydrogen annealing on capacitance–voltage (C–V) characteristics and interface-state density (D_it) of 4H–SiC metal–oxide–semiconductor (MOS) structures have been investigated. The D_it was reduced to as low as... (Read more)

Semi-insulating 6H–SiC crystals have been achieved by using controlled doping with deep-level vanadium impurities. High resistivity undoped and semi-insulating vanadium-doped single-crystals with diameters up to 50 mm were grown by physical vapor transport using an induction-heated, cold-wall... (Read more)

We demonstrate the drift of a donor-passivating hydrogen species under the action of the electric field in the depletion region of a reverse-biased Au/n-Si Schottky diode hydrogenated by exposure to a low-frequency discharge. The redistribution is explained by the unidirectional drift of a... (Read more)

It is observed that the linewidth and line shape of the Zeeman resonance associated with dangling bonds at the (111)Si-SiO₂ interface (P_b centers) vary with the direction of the applied magnetic field. An analysis of the line shape of this resonance indicates that it can be... (Read more)

B-doped Si wafers were subjected to atomic-deuterium (D) plasmas to simulate the reactions of atomic hydrogen with substitutional B acceptor levels. Secondary ion mass spectrometry was used to profile the in- and out-diffusion of D, and spreading resistance was used to measure the distribution of... (Read more)

It was recently proposed that hydrogen compensation of shallow-acceptor impurities in single-crystal silicon is due to the diffusion of both monatomic oxygen and hydrogen into silicon which combine at acceptor sites to form neutral acceptor-OH complexes. It is shown here that oxygen does not diffuse... (Read more)

Experimental results are presented which identify the following chemical reaction as being responsible for compensation of shallow-acceptor impurities when single-crystal silicon is exposed to monatomic hydrogen: A^-+h⁺+H⁰↔(AH)⁰, where A^-... (Read more)

Amorphous SiOx-layers with O < x < 2 have been prepared by evaporation of Si at oxygen pressures of 10−6 … 10−3 mbar. The composition of the samples was determined by proton backscattering. The band gap, derived from optical measurements, increases with rising oxygen... (Read more)