Continuum modeling of post-implantation damage and the effective plus factor in crystalline silicon at room temperature

The silicon substrates were hydrogenated at approximately room temperature and hydrogen concentration profiles vs. depth have been measured by SIMS. Czochralski grown (CZ) wafers, both n- and p-type conductivity, were used in the experiments under consideration. For analysis of hydrogen transport processes and quasichemical reactions the model of hydrogen atoms diffusion and quasichemical reactions is proposed and the set of equations is obtained. The developed model takes into account the formation of bound hydrogen in the near surface region, hydrogen transport as a result of diffusion of hydrogen molecules 2 H , diffusion of metastable complexes * 2 H and diffusion of nonequilibrium hydrogen atoms. Interaction of 2 H with oxygen atoms and formation of immobile complexes “oxygen atom - hydrogen molecule” (O - H2 ) is also taken into account to explain the hydrogen concentration profiles in the substrates of n-type conductivity. The computer simulation based on the proposed equations has shown a good agreement of the calculated hydrogen profiles with the experimental data and has allowed receiving a value of the hydrogen molecules diffusivity at room temperature.

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Photoluminescence of Erbium-Diffused Silicon

MRS Proceedings ◽

10.1557/proc-422-81 ◽

1996 ◽

Vol 422 ◽

Author(s):

H. Horiguchi ◽

T. Kinone ◽

R. Saito ◽

T. Kimura ◽

T. Ikoma

Keyword(s):

Room Temperature ◽

Crystalline Silicon ◽

Luminescence Spectra ◽

Main Peak ◽

Silicon Substrates ◽

Annealing Atmosphere ◽

Full Width ◽

Half Maximum ◽

Strong Luminescence ◽

Fine Structures

AbstractErbium films are evaporated on crystalline silicon substrates and are thermally diffused into silicon in an Ar+02 or H2 flow. Very sharp Er3+-related luminescence peaks are observed around 1.54 μ m.The main peak as well as the fine structures of the luminescence spectra depend on the annealing atmosphere, suggesting different luminescence centers. The full width at half maximum (FWHM) of the main peaks is ≤ 0.5nm at 20K. Thermal diffusion with Al films on top of the Er films is found to increase the intensity of the Er3+-related peaks greatly. The temperature dependence between 20 K and room temperature is relatively small, and a strong luminescence is obtained at room temperature.

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Room Temperature Band-Edge Luminescence from Silicon Grains Prepared by the Recrystallization of Mesoporous Silicon

MRS Proceedings ◽

10.1557/proc-452-517 ◽

1996 ◽

Vol 452 ◽

Author(s):

Karen L. Moore ◽

Leonid Tsybeskov ◽

Philippe M. Fauchet ◽

Dennis G. Hall

Keyword(s):

Room Temperature ◽

Silicon Oxide ◽

Crystalline Silicon ◽

Band Edge ◽

Applied Bias ◽

Mesoporous Silicon ◽

Room Temperature Photoluminescence ◽

Band Edge Luminescence ◽

A Current ◽

Better Than

AbstractRoom-temperature photoluminescence (PL) peaking at 1.1 eV has been found in electrochemically etched mesoporous silicon annealed at 950°C. Low-temperature PL spectra clearly show a fine structure related to phonon-assisted transitions in pure crystalline silicon (c-Si) and the absence of defect-related (e.g.P-line) and impurity-related (e.g.oxygen, boron) transitions. The maximum PL external quantum efficiency (EQE) is found to be better than 0.1% with a weak temperature dependence in the region from 12K to 400K. The PL intensity is a linear function of excitation intensity up to 100 W/cm2. The PL can be suppressed by an external electric field ≥ 105 V/cm. Room temperature electroluminescence (EL) related to the c-Si band-edge is also demonstrated under an applied bias ≤ 1.2 V and with a current density ≈ 20 mA/cm2. A model is proposed in which the radiative recombination originates from recrystallized Si grains within a non-stoichiometric Si-rich silicon oxide (SRSO) matrix.

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Electrical and Structural Properties of Al-Implanted and Annealed 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.343 ◽

2007 ◽

Vol 556-557 ◽

pp. 343-346 ◽

Cited By ~ 3

Author(s):

M. Obernhofer ◽

Michael Krieger ◽

Frank Schmid ◽

Heiko B. Weber ◽

Gerhard Pensl ◽

...

Keyword(s):

Hall Effect ◽

Structural Properties ◽

Room Temperature ◽

Annealing Temperature ◽

Rutherford Backscattering ◽

Electrical Activation ◽

Implantation Damage ◽

Aluminum Ions

Aluminum ions (Al+) were implanted at room temperature or at 500°C into n-type 4HSiC. The implantation damage (displaced Si atoms) and the electrical activation of Al+ ions (concentration of Al acceptors) were determined by Rutherford backscattering in channeling mode and Hall effect, respectively, as a function of the annealing temperature.

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Room-temperature macromolecular crystallography using a micro-patterned silicon chip with minimal background scattering

Journal of Applied Crystallography ◽

10.1107/s1600576716006348 ◽

2016 ◽

Vol 49 (3) ◽

pp. 968-975 ◽

Cited By ~ 53

Author(s):

Philip Roedig ◽

Ramona Duman ◽

Juan Sanchez-Weatherby ◽

Ismo Vartiainen ◽

Anja Burkhardt ◽

...

Keyword(s):

Data Collection ◽

Room Temperature ◽

Structural Changes ◽

Crystalline Silicon ◽

Background Level ◽

Sample Holder ◽

Macromolecular Crystallography ◽

Recent Success ◽

Millisecond Range ◽

Humidified Air

Recent success at X-ray free-electron lasers has led to serial crystallography experiments staging a comeback at synchrotron sources as well. With crystal lifetimes typically in the millisecond range and the latest-generation detector technologies with high framing rates up to 1 kHz, fast sample exchange has become the bottleneck for such experiments. A micro-patterned chip has been developed from single-crystalline silicon, which acts as a sample holder for up to several thousand microcrystals at a very low background level. The crystals can be easily loaded onto the chip and excess mother liquor can be efficiently removed. Dehydration of the crystals is prevented by keeping them in a stream of humidified air during data collection. Further sealing of the sample holder, for example with Kapton, is not required. Room-temperature data collection from insulin crystals loaded onto the chip proves the applicability of the chip for macromolecular crystallography. Subsequent structure refinements reveal no radiation-damage-induced structural changes for insulin crystals up to a dose of 565.6 kGy, even though the total diffraction power of the crystals has on average decreased to 19.1% of its initial value for the same dose. A decay of the diffracting power by half is observed for a dose ofD1/2= 147.5 ± 19.1 kGy, which is about 1/300 of the dose before crystals show a similar decay at cryogenic temperatures.

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Light Emission from Intrinsic and Doped Silicon-Rich Silicon Oxide: from the Visible to 1.6 ΜM

MRS Proceedings ◽

10.1557/proc-452-523 ◽

1996 ◽

Vol 452 ◽

Cited By ~ 2

Author(s):

L. Tsybeskov ◽

K. L. Moore ◽

P. M. Fauchet ◽

D. G. Hall

Keyword(s):

Rare Earth ◽

External Quantum Efficiency ◽

Room Temperature ◽

Structural Modification ◽

Silicon Oxide ◽

Light Emission ◽

Crystalline Silicon ◽

Light Emitting ◽

Infra Red ◽

Doped Silicon

AbstractSilicon-rich silicon oxide (SRSO) films were prepared by thermal oxidation (700°C-950°C) of electrochemically etched crystalline silicon (c-Si). The annealing-oxidation conditions are responsible for the chemical and structural modification of SRSO as well as for the intrinsic light-emission in the visible and near infra-red spectral regions (2.0–1.8 eV, 1.6 eV and 1.1 eV). The extrinsic photoluminescence (PL) is produced by doping (via electroplating or ion implantation) with rare-earth (R-E) ions (Nd at 1.06 μm, Er at 1.5 μm) and chalcogens (S at ∼1.6 μm). The impurities can be localized within the Si grains (S), in the SiO matrix (Nd, Er) or at the Si-SiO interface (Er). The Er-related PL in SRSO was studied in detail: the maximum PL external quantum efficiency (EQE) of 0.01–0.1% was found in samples annealed at 900°C in diluted oxygen (∼ 10% in N2). The integrated PL temperature dependence is weak from 12K to 300K. Light emitting diodes (LEDs) with an active layer made of an intrinsic and doped SRSO are manufactured and studied: room temperature electroluminescence (EL) from the visible to 1.6 μmhas been demonstrated.

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Effects of the Subsequent Ion Irradiation on the Formation Process of β-SiC from Si-C Mixtures Fabricated on Si by Ion Implantation

MRS Proceedings ◽

10.1557/proc-97-289 ◽

1987 ◽

Vol 97 ◽

Author(s):

Tadamasa Kimura ◽

Hiroyuki Yamaguchi ◽

Shigemi Yugo ◽

Yoshio Adachi

Keyword(s):

Activation Energy ◽

Ion Implantation ◽

Infrared Absorption ◽

Formation Process ◽

Room Temperature ◽

Ion Irradiation ◽

Infrared Absorption Spectroscopy ◽

Energetic Ions ◽

Mixed Layers ◽

Post Implantation

ABSTRACTThe β-SiC formation process through post-implantation annealing of Si-C mixtures fabricated on Si by C-ion implantation at room temperature is studied by means of infrared absorption spectroscopy. It is shown that the formation of B-SiC from the Si-C mixtures is greatly enhanced by the subsequent irradiation of other energetic ions prior to the thermal annealing. The continuous amorphization of the Si-C mixed layers is considered to be the dominant cause for the enhancement of the B-SiC formation. The activation energy of the β-SiC formation process which is 5.3 eV without irradiation is reduced to 4.0 eV by the irradiation of 150 keV, 1 × 1017/cm2 Ar ions.

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The Effect of Hydrogen/ Deuterium Introduction on Photoluminescence of 3C-SiC Crystals

MRS Proceedings ◽

10.1557/proc-513-445 ◽

1998 ◽

Vol 513 ◽

Cited By ~ 1

Author(s):

B. K. Lee ◽

A. J. Steckl ◽

J. M. Zavada ◽

R. G. Wilson

Keyword(s):

Room Temperature ◽

Annealing Temperature ◽

Laser Excitation ◽

Peak Wavelength ◽

Final Annealing ◽

Increasing Trend ◽

Area Increase ◽

Hydrogen Deuterium ◽

Pl Intensity ◽

Post Implantation

ABSTRACTThe effect of the incorporation and annealing of deuterium in 3C-SiC on its photoluninescence is reported. A 3C-SiC crystal has been implanted with 100 keV deuterium and subsequently annealed at temperatures between 1015 °C and 1220 °C for 1 to 5 minutes. SIMS depth profiles indicate hydrogen is strongly trapped by defects generated through ion bombardment, but a gradual damage repairing occurs during annealing. Photoluminescence was measured with 488 nm Ar laser excitation for sample temperatures from 89 K to 400 K. The PL peak wavelength of 540 nm at room temperature has shifted to 538 nm at 89 K. The peak PL intensity decreases with measurement temperature while its full width at half maximum (FWHM) exhibits an increasing trend. PL data were taken at five annealing stages. The post-implantation peak PL intensity and its integrated area increase initially with annealing temperature and time. After the final annealing at 1218 °C for 2 minute, PL intensity and its integrated area exhibit a decrease in level.

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Room Temperature Boron Diffusion in Amorphous Silicon

MRS Proceedings ◽

10.1557/proc-0912-c02-01 ◽

2006 ◽

Vol 912 ◽

Author(s):

Jeannette M. Jacques ◽

Kevin S. Jones ◽

Mark E. Law ◽

Lance S. Robertson ◽

Leonard M. Rubin ◽

...

Keyword(s):

Amorphous Silicon ◽

Amorphous Materials ◽

Room Temperature ◽

Trapping Site ◽

Concentration Change ◽

Boron Diffusion ◽

Dopant Distribution ◽

Post Implantation ◽

Site Population ◽

Trapping Sites

AbstractAs millisecond annealing is increasingly utilized, the as-implanted profile dominates the final dopant distribution. We characterized boron diffusion in amorphous silicon prior to post-implantation annealing. SIMS confirmed that both fluorine and germanium enhance boron motion in amorphous materials. The magnitude of boron diffusion in germanium amorphized silicon scales with increasing fluorine dose. Boron atoms are mobile at concentrations approaching 1x1019 atoms/cm^3. It appears that defects inherent to the structure of amorphous silicon can trap and immobilize boron atoms at room temperature, but that chemical reactions involving Si-F and Si-Ge eliminate potential trapping sites. Sequential Ge+, F+, and B+ implants result in 80% more boron motion than do sequential Si+, F+, and B+ implants. The mobile boron dose and trapping site concentration change as functions of the fluorine dose through power law relationships. As the fluorine dose increases, the trapping site population decreases and the mobile boron dose increases. This reduction in trap density can result in as-implanted “junction depths” that are as much as 75% deeper (taken at 1x1018 atoms/cm-3) for samples implanted with 500 eV, 1x1015 atoms/cm2 boron.

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High Dose Al+ Implanted and Microwave Annealed 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.817 ◽

2012 ◽

Vol 717-720 ◽

pp. 817-820

Author(s):

Roberta Nipoti ◽

A. Nath ◽

Mulpuri V. Rao ◽

Anders Hallén ◽

F. Mancarella ◽

...

Keyword(s):

Room Temperature ◽

Electrical Activation ◽

High Dose ◽

Annealing Temperatures ◽

Microwave Annealing ◽

Post Implantation

A post implantation microwave annealing technique has been applied for the electrical activation of Al+ implanted ions in semi-insulating 4H-SiC. The annealing temperatures have been 2000-2100°C. The implanted Al concentration has varied from 5 x 1019 to 8 x 1020 cm-3. A minimum resistivity of 2 x 10-2 Ω∙cm and about 70% electrical activation of the implanted Al has been measured at room temperature for an implanted Al concentration of 8 x 1020 cm-3 and a microwave annealing at 2100°C for 30 s.

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