Localization of Hydrogen in B and in Doped Silicon by ion Channeling and PAC

1987 ◽  
Vol 104 ◽  
Author(s):  
Th. Wichert ◽  
H. Skudlik ◽  
H. -D. Carstanjen ◽  
T. Enders ◽  
M. Deicher ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Lattice Site ◽  
Ion Beam ◽  
Tetrahedral Site ◽  
Ion Channeling ◽  
Pac Technique ◽  
Doped Silicon ◽  
Bond Center ◽  
Silicon Doped ◽  
Center Site

ABSTRACTThe lattice site of H/D atoms in silicon doped with B and 111In atoms is investigated using the ion channeling and perturbed γγ angular correlation (PAC) technique. The results indicate that at 295 K the antibonding site is occupied by H/D and that this site is easily transformed into a near tetrahedral site under the influence of an analyzing ion beam. Based on PAC results, the population of a second site, possibly a bond-center site, is expected at low temperatures.

Optical Properties of Novel Vibronic Bands in Electron-Irradiated Tin Doped Silicon

1989 ◽  
Vol 163 ◽  
Author(s):  
J. H. Svensson ◽  
B. Monemar ◽  
B. G. Svensson
Keyword(s):  
Optical Properties ◽  
Low Temperatures ◽  
Excited Electronic State ◽  
Electronic States ◽  
Optical Excitation ◽  
Electronic Transitions ◽  
Vibrational States ◽  
Doped Silicon ◽  
Silicon Doped ◽  
Excitation Conditions

AbstractThe optical absorption of two new electronic transitions in silicon doped with tin has been investigated. At low temperatures two no-phonon lines are observed at 2755.3 and 4112.2 cm-1, each with strong coupling to a single quasi-localized vibration in the excited electronic state. These vibrations have quantum energies of 69.6 and 70.2 cm-1, respectively. At higher temperatures coupling to thermally excited vibrational states in the ground electronic states is observed for both lines. The transition with the no-phonon line at 4112.2 cm-1 has been studied in detail and is found to be well described using the adiabatic and Condon approximations. The optical properties of the two transitions are found to be quite similar. Moreover the relative intensities of the two lines are found to be dependent on the optical excitation conditions.

Direct Formation of Thin Films and Epitaxial Overlayers at low Temperatures Using a Low-Energy (10–;500 ev) Ion Beam Deposition System

1987 ◽  
Vol 93 ◽  
Author(s):  
R. A. Zuhr ◽  
G. D. Alton ◽  
B. R. Appleton ◽  
N. Herbot ◽  
T. S. Noggle ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Solid Phase ◽  
Ion Beam ◽  
National Laboratory ◽  
Ion Source ◽  
Low Energy ◽  
Oak Ridge ◽  
Ion Channeling ◽  
Ion Beam Deposition ◽  
Beam Deposition

ABSTRACTA low-energy ion beam deposition system has been developed at Oak Ridge National Laboratory and has been applied successfully to the growth of epitaxial films at low temperatures for a number of different elements. The deposition system utilizes the ion source and optics of a commercial ion implantation accelerator. The 35 keV mass- and energy-analyzed ion beam from the accelerator is decelerated in a four-element electrostatic lens assembly to energies between 10 and 500 eV for direct deposition onto a target under UHV conditions. Current densities on the order of 10 A/cm are achieved with good uniformity over a 1.4 cm diameter spot. The completed films are characterized by Rutherford backscattering, ion channeling, cross-section transmission electron microscopy, and x-ray diffraction. The effects of substrate temperature, ion energy, and substrate cleaning have been studied. Epitaxial overlayers which show good minimum yields by ion channeling (3–4%) have been produced at temperatures as low as 375°C for Si on Si(100) and 250°C for Ge on Ge(100) at growth rates that exceed the solid-phase epitaxy rates at these temperatures by more than an order of magnitude.

Lattice site location of ultra-shallow implanted B in Si using ion beam analysis

2001 ◽  
Vol 669 ◽  
Author(s):  
Hajime Kobayashi ◽  
Ichiro Nomachi ◽  
Susumu Kusanagi ◽  
Fumitaka Nishiyama
Keyword(s):  
Ion Implantation ◽  
Lattice Site ◽  
Rutherford Backscattering Spectrometry ◽  
Hole Concentration ◽  
Ion Beam ◽  
Nuclear Reaction Analysis ◽  
High Dose ◽  
Site Location ◽  
Ion Channeling ◽  
Implantation Damage

ABSTRACTWe have investigated the lattice site location of B in Si using ion channeling in combination with nuclear reaction analysis (NRA). Silicon samples implanted with Boron at an energy of 10 keV and a dose of 5 × 1014 cm−2 (low dose samples) or 5 × 1015 cm−2 (high dose samples) were annealed at 1000 °C for 10 seconds (RTA) or at 800 °C for 10 minutes (FA). The activation efficiencies of these samples were estimated from the B atomic concentration and the hole concentration obtained by secondary ion mass spectrometry (SIMS) and spreading resistance profiling (SRP), respectively. We also studied the ion implantation damage of Si crystals using ion channeling combined with Rutherford backscattering spectrometry (RBS). We found that the activation efficiency is proportional to the substitutionality, meaning that substitutional B is fully activated without any carrier compensation. We also found that B atoms go to the substitutional sites and are activated up to the solubility limit in the high dose samples. However, the ion implantation damage of the crystalline Si in the high dose samples increases somewhat after annealing.

scholarly journals An Investigation on the Lattice Site Location of the Excess Arsenic Atoms in GaAs layers Grown by Low Temperature Molecular Beam Epitaxy

1991 ◽  
Vol 241 ◽  
Author(s):  
Kin Man Yu ◽  
Z. Liliental-Weber
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Lattice Site ◽  
Tetrahedral Site ◽  
Site Location ◽  
X Ray ◽  
Ion Channeling ◽  
Transmission Electron ◽  
A Site ◽  
Substrate Temperatures

ABSTRACTWe have measured the excess As atoms present in GaAs layers grown by molecular beam epitaxy at low substrate temperatures using particle induced x-ray emission technique. The amount of excess As atoms in layers grown by MBE at 2000C were found to be ∼4×1020 cm−2. Subsequent annealing of the layers under As overpressure at 600'C did not result in any substantial As loss. However, transmission electron microscopy revealed that As precipitates (2- 5nm in diameter) were present in the annealed layers. The lattice location of the excess As atoms in the as grown layers was investigated by ion channeling methods. Angular scans were performed in the <110> axis of the crystal. Our resutls strongly suggest that a, arge fraction of these excess As atoms are located in an interstitial position close to an As row. These As “intersitials” are located at a site slightly displaced from the tetrahedral site in a diamond cubic lattice. No interstitial As signal is observed in the annealed layers.

scholarly journals Highly efficient THz four-wave mixing in doped silicon

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Nils Dessmann ◽  
Nguyen H. Le ◽  
Viktoria Eless ◽  
Steven Chick ◽  
Kamyar Saeedi ◽  
...  
Keyword(s):  
Four Wave Mixing ◽  
Wave Mixing ◽  
Optical Nonlinearities ◽  
Third Order ◽  
Picosecond Pulses ◽  
Light Pulses ◽  
A Value ◽  
Doped Silicon ◽  
Perturbative Regime ◽  
Silicon Doped

AbstractThird-order non-linearities are important because they allow control over light pulses in ubiquitous high-quality centro-symmetric materials like silicon and silica. Degenerate four-wave mixing provides a direct measure of the third-order non-linear sheet susceptibility χ(3)L (where L represents the material thickness) as well as technological possibilities such as optically gated detection and emission of photons. Using picosecond pulses from a free electron laser, we show that silicon doped with P or Bi has a value of χ(3)L in the THz domain that is higher than that reported for any other material in any wavelength band. The immediate implication of our results is the efficient generation of intense coherent THz light via upconversion (also a χ(3) process), and they open the door to exploitation of non-degenerate mixing and optical nonlinearities beyond the perturbative regime.

Search for Ion Induced Mixing in Ceramic-Ceramic Systems

1995 ◽  
Vol 396 ◽  
Author(s):  
K.R. Padmanabhan
Keyword(s):  
Auger Electron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Ion Beam ◽  
Epitaxial Films ◽  
Ion Beam Mixing ◽  
Ceramic Substrates ◽  
Ion Channeling ◽  
Ceramic Films ◽  
Dose Dependent

AbstractThin sputtered ceramic films deposited on ceramic substrates were subjected to either Kr+ or Xe+ ion bombardment for ion beam mixing studies in ceramic-ceramic systems. The amount of mixing if any was evaluated from Rutherford backscattering and Auger electron spectroscopy. In some instances ceramic films were deposited on epitaxial films or single crystal substrates for ion channeling analysis. No significant mixing was observed in any of the systems with ZrC. However, analysis of the interface in Si3N4/ SiC system indicates appreciable mixing and ion beam induced damage to the substrate. The mixing appears to be dose dependent for heavier ions.

The Complementary Nature of Electron Microscopy and ION Channeling for the Assessment of Radiation Damage Evolution in Ceramics

1998 ◽  
Vol 4 (S2) ◽  
pp. 558-559
Author(s):  
K. E. Sickafus
Keyword(s):  
Damage Evolution ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Quantitative Measure ◽  
Heavy Ion ◽  
Damage Parameter ◽  
Irradiation Damage ◽  
Damage Level ◽  
Ion Channeling ◽  
Typical Experiment

In ion irradiation damage studies on ceramics, damage evolution is often assessed using Rutherford backscattering spectroscopy and ion channeling (RBS/C) techniques. In a typical experiment, a single crystal ceramic sample is irradiated with heavy ions and then the crystal is exposed to He ions along a low-index crystallographic orientation. Simultaneously, the backscattered He ion yield is measured as a function of ion energy loss. For He ions scattered from the heavy ion irradiated volume, the He ion yield increases in proportion to the heavy ion dose. The RBS/C yield rises because the He ion beam is dechanneled by, for instance, interstitial point defects and clusters and their associated strain fields. A quantitative measure of dechanneling is denoted by χmin, defined as the ratio of the He ion yield along a low-index crystal orientation, to the yield obtained in a random (non-channeling) orientation. The damage parameter xmin varies from 0 to 1, where 1 represents the maximum damage level that can be measured by RBS/C.

Theoretical Studies of Structure and Doping of Hydrogenated Amorphous Silicon

2011 ◽  
Vol 1321 ◽  
Author(s):  
Bin Cai ◽  
D. A. Drabold
Keyword(s):  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Theoretical Studies ◽  
Defect States ◽  
High Impurity ◽  
Bond Center ◽  
B Doping ◽  
Hydrogenated Amorphous ◽  
Center Site

ABSTRACTIn a-Si:H, large concentrations of B or P (of order 1%) are required to dope the material, suggesting that doping mechanisms are very different than for the crystal for which much smaller concentrations are required. In this paper, we report simulations on B and P introduced into realistic models of a-Si:H and a-Si, with concentrations ranging from 1.6% to 12.5% of B or P in the amorphous host. The results indicate that tetrahedral B and P are effective doping configurations in a-Si, but high impurity concentrations introduce many defect states. For a-Si:H, we report that both B(3,1) and P(3,1) (B or P atom bonded with three Si atoms and one H atom) are effective doping configurations. We investigate H passivation in both cases. For both B and P, there exists a “hydrogen poison range” of order 6 Å for which H in a bond-center site can suppress doping. For B doping, nearby H prefers to stay at the bond-center of Si-Si, leaves B four-fold and neutralizes the doping configuration; for P doping, nearby H spoils the doping by inducing a reconstruction rendering initially tetrahedral P three-fold.

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