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

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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Intense Photoluminescence and Photoluminescence Enhancement of Silicon Nanocrystals by Ultraviolet Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.31.74 ◽

2007 ◽

Vol 31 ◽

pp. 74-76 ◽

Cited By ~ 3

Author(s):

P.T. Huy ◽

P.H. Duong

Keyword(s):

Silicon Nanocrystals ◽

Room Temperature ◽

Laser Excitation ◽

Uv Light ◽

Irradiation Time ◽

Excitation Wavelength ◽

Nonradiative Recombination ◽

Emission Yield ◽

Recombination Centers ◽

Pl Intensity

Photoluminescence (PL) from silicon nanocrystals deposited on top of silica-glass template and from silicon nanocrystals in nc_Si/SiO2 multilayer films were studied as a function of ultraviolet (UV) laser irradiation time in vacuum. Both the films exhibit intense visible PL at room temperature under laser excitation. It was found that upon prolong irradiation time using a He-Cd laser (325 nm) the PL intensity of the films was spectacularly enhanced. The process is reversible and does not happen with excitation wavelength longer than 400 nm. Upon introducing air into the measurement chamber, a rapid decrease of the PL intensity was recorded. This observation suggests that the UV light may lead to modification of nonradiative recombination centers in the films and thus improves the emission yield of silicon nanocrystals.

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Ion Implanted p+/n Diodes: Post-Implantation Annealing in a Silane Ambient in a Cold-Wall Low-Pressure CVD Reactor

Materials Science Forum ◽

10.4028/www.scientific.net/msf.527-529.819 ◽

2006 ◽

Vol 527-529 ◽

pp. 819-822

Author(s):

Fabio Bergamini ◽

Shailaja P. Rao ◽

Antonella Poggi ◽

Fabrizio Tamarri ◽

Stephen E. Saddow ◽

...

Keyword(s):

Room Temperature ◽

Annealing Temperature ◽

Low Pressure ◽

Cold Wall ◽

Current Voltage Characteristic ◽

Process Yield ◽

Annealing Temperatures ◽

Current Voltage ◽

Post Implantation

This work reports the realization and characterization of 4H-SiC p+/n diodes with the p+ anodes made by Al+ ion implantation at 400°C and post-implantation annealing in silane ambient in a cold-wall low-pressure CVD reactor. The Al depth profile was almost box shaped with a height of 6×1019 cm-3 and a depth of 160 nm. Implant anneals were performed in the temperature range from 1600°C to 1700°C. As the annealing temperature was increased, the silane flow rate was also increased. This annealing process yields a smooth surface with a roughness of the implanted area of 1.7 - 5.3 nm with increasing annealing temperature. The resistivity of the implanted layer, measured at room temperature, decreased for increasing annealing temperatures with a minimum value of 1.4 0-cm measured for the sample annealed at 1700°C. Considering only the current-voltage characteristic of a diode that could be modeled as an abrupt p/n junction within the frame of the Shockley theory, the diode process yield and the diode leakage current decreased, respectively, from 93% to 47% and from 2×10-7 Acm-2 to 1×10-8 Acm-2 at 100 V reverse bias, for increasing post implantation annealing temperature.

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Preparation of Ferroelectric BaTiO3 Films by Electrophoretic Deposition Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.87 ◽

2007 ◽

Vol 336-338 ◽

pp. 87-90

Author(s):

Ya Lu Ma ◽

Yu Zhang ◽

Hong Long Zhu

Keyword(s):

Dielectric Constant ◽

Barium Titanate ◽

Electrophoretic Deposition ◽

Room Temperature ◽

Annealing Temperature ◽

Ferroelectric Films ◽

Final Annealing ◽

Xrd Pattern ◽

Uniform Microstructure ◽

Room Temperature Dielectric Constant

Barium titanate ferroelectric films on Pt substrates were fabricated by electrophoretic deposition (EPD) technique. The barium titanate films sintered at different temperature (600°C, 900°C, 1050°C, 1150°C, 1200°C) for 2h, which were prepared via repeated EPD-sintering route 2~3 times were sufficiently dense and had uniform microstructure. The XRD pattern and SEM microphotography have been measured in order to investigate the effects of the final annealing temperature on the phase compositions and microstructure of the film. The experiment results showed that barium titanate films were crystallized into the tetragonal phase at 1050°C and above. The room temperature dielectric constant (ε) and loss tangent (tanδ) at 1kHz were respectively determined for different samples sintered at 600°C, 900°C, 1050°C, 1150°C and 1200°C. Both ε and tanδ showed anomaly peaks at 125°C. The results showed that typical BaTiO3 films sintered at 1050°C having higher dielectric constant (ε=2300) and lower dielectric loss (tanδ=0.02). The room temperature remanant polarization (Pr) and coercive field (EC) were found to be 1.9μC/cm2 and 35kV/cm, respectively.

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Recombination Enhanced Defect Annealing in 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.483-485.369 ◽

2005 ◽

Vol 483-485 ◽

pp. 369-372 ◽

Cited By ~ 3

Author(s):

L. Storasta ◽

F.H.C. Carlsson ◽

Peder Bergman ◽

Erik Janzén

Keyword(s):

Electron Irradiation ◽

Room Temperature ◽

Annealing Temperature ◽

Laser Excitation ◽

Pin Diode ◽

Defect Annealing ◽

Low Energy Electron ◽

Transient Spectroscopy ◽

Capacitance Transient ◽

Transient Measurements

Recombination enhanced defect annealing of intrinsic defects in 4H-SiC, created by low energy electron irradiation, has been observed. A reduction the defect concentration at temperature lower than the normal annealing temperature of 400º C and 800°C is observed after either above bandgap laser excitation or forward biasing of a pin-diode. The presence of the defects has been studied both electrically and optically using capacitance transient spectroscopy and low temperature photoluminescence. Photoluminescence measurements show that several lines, normally detected after electron irradiation, have almost or entirely disappeared by recombination enhanced annealing at room temperature. From capacitance transient measurements, the annealing enhancement is found to be largest for the HS2 hole trap, while the EH1 and EH3 electron traps also anneal out by recombination enhanced reaction but at a lower rate.

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Degradation in a Methyl-phenyl Co-Polymeric Polysilane for LED Applications

MRS Proceedings ◽

10.1557/proc-769-h4.3 ◽

2003 ◽

Vol 769 ◽

Cited By ~ 2

Author(s):

Asha Sharma ◽

Deepak ◽

Monica Katiyar ◽

Satyendra Kumar ◽

V. Chandrasekhar ◽

...

Keyword(s):

Thin Films ◽

Molecular Weight ◽

Light Source ◽

Room Temperature ◽

Light Exposure ◽

Room Temperature Photoluminescence ◽

Pl Spectrum ◽

Pl Intensity ◽

Methyl Phenyl

AbstractThe optical degradation of polysilane copolymer has been studied in spin cast thin films and solutions using light source of 325 nm wavelength. The room temperature photoluminescence (PL) spectrum of these films show a sharp emission at 368 nm when excited with a source of 325 nm. However, the PL intensity deteriorates with time upon light exposure. Further the causes of this degradation have been examined by characterizing the material for its transmission behaviour and changes occurring in molecular weight as analysed by GPC data.

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Effect of Annealing temperature on the Structural and Magnetic Properties of TbxY3-xFe5O12(x = 0.0, 1.0, 2.0) Thin Films Prepared by Sol-Gel Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.501.236 ◽

2012 ◽

Vol 501 ◽

pp. 236-241 ◽

Cited By ~ 1

Author(s):

Ftema W. Aldbea ◽

Noor Bahyah Ibrahim ◽

Mustafa Hj. Abdullah ◽

Ramadan E. Shaiboub

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Room Temperature ◽

Annealing Temperature ◽

Sol Gel ◽

Vibrating Sample Magnetometer ◽

X Ray ◽

Garnet Phase ◽

Sol Gel Process ◽

Amorphous Structures

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

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Nonlinear Optical Response of a WS2 Monolayer at Room Temperature upon Multicolor Laser Excitation

ACS Photonics ◽

10.1021/acsphotonics.0c01567 ◽

2021 ◽

Vol 8 (2) ◽

pp. 550-556

Author(s):

Javier Hernandez-Rueda ◽

Marc L. Noordam ◽

Irina Komen ◽

L. Kuipers

Keyword(s):

Nonlinear Optical ◽

Room Temperature ◽

Laser Excitation ◽

Optical Response ◽

Nonlinear Optical Response ◽

Ws2 Monolayer

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Structural Changes of UHV Deposited Titanium Thin Films in Presence of Oxygen Flow and Temperature

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.1094 ◽

2011 ◽

Vol 110-116 ◽

pp. 1094-1098

Author(s):

Haleh Kangarlou ◽

Mehdi Bahrami Gharahasanloo ◽

Akbar Abdi Saray ◽

Reza Mohammadi Gharabagh

Keyword(s):

Room Temperature ◽

Structural Changes ◽

Annealing Temperature ◽

Annealing Process ◽

Oxygen Flow ◽

Glass Substrates ◽

Annealing Temperatures ◽

Titanium Thin Films ◽

Deposition Angle ◽

Ti Films

Ti films of same thickness, and near normal deposition angle, and same deposition rate were deposited on glass substrates, at room temperature, under UHV conditions. Different annealing temperatures as 393K, 493K and 593K with uniform 8 cm3/sec, oxygen flow, were used for producing titanium oxide layers. Their nanostructures were determined by AFM and XRD methods. Roughness of the films changed due to annealing process. The gettering property of Ti and annealing temperature can play an important role in the nanostructure of the films.

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