Control of and Mechanisms for Room Temperature Visible light Emission from Silicon Nanostructures in SiO2 formed by Si+ Ion Implantation

1994 ◽  
Vol 358 ◽  
Author(s):  
T. Komoda ◽  
J.P. Kelly ◽  
A. Nejm ◽  
K.P. Homewood ◽  
P.L.F Hemment ◽  
...  
Keyword(s):  
Quantum Confinement ◽  
Room Temperature ◽  
Light Emission ◽  
Silicon Nanostructures ◽  
Two Phase ◽  
Population Distributions ◽  
Si Nanocrystals ◽  
Induced Defects ◽  
Irradiation Induced Defects ◽  
Si Ion Implantation

ABSTRACTImplantation of Si+ ions into thermal oxides grown on silicon has been used to synthesise a two phase structure consisting of Si nanocrystals in a SiO2 matrix. Various processing conditions have been used in order to modify the size and population distributions of the Si inclusions. Photoluminescence spectra have been recorded from samples annealed in nitrogen, forming gas and oxygen. Both red and blue shifts of the luminescence peaks have been observed. It is concluded that the photoluminescence is a consequence of the effects of quantum confinement but is also dependent on the presence of irradiation-induced defects or Si/SiO2 interface states.

Reverse martensitic phase transformation induced in Nb–Co multilayers by ion irradiation

1994 ◽  
Vol 9 (2) ◽  
pp. 357-361 ◽  
Author(s):  
B.X. Liu ◽  
Z.J. Zhang
Keyword(s):  
Phase Transformation ◽  
High Temperature ◽  
Solid State ◽  
Room Temperature ◽  
Ion Irradiation ◽  
Martensitic Phase ◽  
Martensitic Phase Transformation ◽  
Step Transition ◽  
Induced Defects ◽  
Irradiation Induced Defects

A reverse martensitic phase transformation was observed in Nb-enriched Nb-Co multilayers induced by room temperature 200 ke V xenon ion mixing. Further experiments revealed that this bcc-fcc transition proceeds in two steps, i.e., bcc-hcp and hcp-fcc. A crystallographic model is proposed to explain the two-step transition through shearing and sliding, which are mediated by irradiation-induced defects and strain in the films. In addition, the existence of the hcp and fcc metastable states in the Nb-Co system was confirmed by high-temperature solid state interdiffusion of the corresponding multilayers.

scholarly journals InPBi Quantum Dots for Super-Luminescence Diodes

Nanomaterials ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 705 ◽  
Author(s):  
Liyao Zhang ◽  
Yuxin Song ◽  
Qimiao Chen ◽  
Zhongyunshen Zhu ◽  
Shumin Wang
Keyword(s):  
Quantum Confinement ◽  
Room Temperature ◽  
Light Emission ◽  
Wide Spectrum ◽  
Active Material ◽  
Low Light ◽  
Center Wavelength ◽  
Emission Efficiency ◽  
Spatial Size ◽  
Lattice Matched

InPBi thin film has shown ultra-broad room temperature photoluminescence, which is promising for applications in super-luminescent diodes (SLDs) but met problems with low light emission efficiency. In this paper, InPBi quantum dot (QD) is proposed to serve as the active material for future InPBi SLDs. The quantum confinement for carriers and reduced spatial size of QD structure can improve light emission efficiently. We employ finite element method to simulate strain distribution inside QDs and use the result as input for calculating electronic properties. We systematically investigate different transitions involving carriers on the band edges and the deep levels as a function of Bi composition and InPBi QD geometry embedded in InAlAs lattice matched to InP. A flat QD shape with a moderate Bi content of a few percent over 3.2% would provide the optimal performance of SLDs with a bright and wide spectrum at a short center wavelength, promising for future optical coherence tomography applications.

scholarly journals Fast recovery of ion-irradiation-induced defects in Ge₂Sb₂Te₅ thin films at room temperature

2021 ◽  
Author(s):  
Martin Hafermann ◽  
Robin Schock ◽  
Chenghao Wan ◽  
Jura Rensberg ◽  
Mikhail Kats ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Ion Irradiation ◽  
Fast Recovery ◽  
Induced Defects ◽  
Irradiation Induced Defects

High energy oxygen irradiation-induced defects in Fe-doped semi-insulating indium phosphide by positron annihilation technique

2017 ◽  
Vol 31 (04) ◽  
pp. 1750019
Author(s):  
S. Pan ◽  
A. Mandal ◽  
Md. A. Sohel ◽  
A. K. Saha ◽  
D. Das ◽  
...  
Keyword(s):  
Indium Phosphide ◽  
Positron Annihilation ◽  
Room Temperature ◽  
High Energy ◽  
Average Lifetime ◽  
Defect States ◽  
Positron Trapping ◽  
Radiation Induced ◽  
Induced Defects ◽  
Irradiation Induced Defects

Positron annihilation technique is applied to study the recovery of radiation-induced defects in 140 MeV oxygen (O[Formula: see text]) irradiated Fe-doped semi-insulating indium phosphide during annealing over a temperature region of 25[Formula: see text]C–650[Formula: see text]C. Lifetime spectra of the irradiated sample are fitted with three lifetime components. Trapping model analysis is used to characterize defect states corresponding to the de-convoluted lifetime values. After irradiation, the observed average lifetime of positron [Formula: see text] ps at room temperature is higher than the bulk lifetime by 21 ps which reveals the presence of radiation-induced defects in the material. A decrease in [Formula: see text] occurs during room temperature 25[Formula: see text]C to 200[Formula: see text]C indicating the dissociation of higher order defects, might be due to positron trapping in acceptor-type of defects ([Formula: see text]). A reverse annealing stage is found at temperature range of 250[Formula: see text]C–425[Formula: see text]C for [Formula: see text]-parameter probably due to the migration of vacancies and the formation of vacancy clusters. Increase in [Formula: see text]-parameter from 325[Formula: see text]C to 425[Formula: see text]C indicates the change in the nature of predominant positron trapping sites. Beyond 425[Formula: see text]C, [Formula: see text], [Formula: see text]-parameter and [Formula: see text]-parameter starts decreasing and around 650[Formula: see text]C, [Formula: see text] and [Formula: see text]-parameter approached almost the bulk value showing the annealing out of radiation-induced defects.

PALS and TEM Study on Irradiation Defects of 12Cr-ODS Steels Induced by He/H Ions

2017 ◽  
Vol 373 ◽  
pp. 96-99 ◽  
Author(s):  
Lu Hui Han ◽  
Tao Fa ◽  
Ya Wen Zhao
Keyword(s):  
Ion Implantation ◽  
Room Temperature ◽  
Positron Lifetime ◽  
Fusion Reactor ◽  
Ion Irradiation ◽  
Ods Steels ◽  
The Difference ◽  
Induced Defects ◽  
Irradiation Induced Defects

The purpose of this study is to evaluate the irradiation defects of 12Cr-ODS steels induced by He/H ions, to provide basic understanding concerning development of fusion reactor components. Firstly, single He、H ion implantation and He/H ion co-implantation of 12Cr-ODS steels were performed at room temperature; and then SIMS were used to determine the He/H ion depth; finally, the irradiation induced defects were investigated by PALS and TEM. Characterization of the implanted samples with SIMS shows that He/H ions are mainly distributed at 4-6μm depth, consistent with the SRIM simulation. The PALS results show that the positron lifetime of H ions implanted samples increases slightly with increasing incident ions fluence, while for He and He/H ion implantation it is reversed. In addition, TEM results demonstrate that after irradiation, cavities are created in all samples, and He ion irradiation produce seriously larger damage compared to H ion. The positron lifetime results can be mainly ascribed to the difference of He and H ion interaction with defects.

Room Temperature Steady State and Time Resolved PL Characterization of Ion Irradiation Induced Defects in 6H-SiC

2005 ◽  
Vol 483-485 ◽  
pp. 373-376
Author(s):  
Ricardo Reitano ◽  
M. Zimbone ◽  
Paolo Musumeci ◽  
P. Baeri
Keyword(s):  
Room Temperature ◽  
Carrier Lifetime ◽  
Minority Carrier ◽  
Ion Irradiation ◽  
Minority Carrier Lifetime ◽  
Time Resolved ◽  
Induced Defects ◽  
Irradiation Induced Defects ◽  
Photoluminescence Peak

Photoluminescence (PL) and time resolved PL are well established as important experimental techniques to study electronic properties of SiC. We studied the influence of ionimplantation on the photoluminescence peak at 423nm and the variation of the minority carrier lifetime (MCL).

Irradiation Induced Defects by Fe-Ion in 316L Stainless Steel Studied by Positron Annihilation Spectroscopy

2017 ◽  
Vol 373 ◽  
pp. 155-161
Author(s):  
Xing Zhong Cao ◽  
Er Yang Lu ◽  
Shuo Xue Jin ◽  
Yi Hao Gong ◽  
Yuan Chao Hu ◽  
...  
Keyword(s):  
Room Temperature ◽  
Ion Irradiation ◽  
High Mobility ◽  
Austenitic Stainless Steels ◽  
Positron Beam ◽  
Positron Annihilation Spectroscopy ◽  
Heavy Ion ◽  
Vacancy Defects ◽  
Induced Defects ◽  
Irradiation Induced Defects

Solution annealed type 316L austenitic stainless steels were irradiated using 2 MeV Fe ions at room temperature. The implanted fluences were 2×1012 ions/cm2 and 1×1013 ions/cm2, respectively. Variable mono-energetic positron beam was performed to characterize the evolution of microstructure and irradiation induced defects. Results show that large amount of vacancy defects formed after heavy ion irradiation. In which, some of mono-vacancies might migrate to form small-sized clusters at room temperature. After irradiation, implanted Fe atoms mainly be interstitials atoms, but some Fe atoms might recombine with vacancies due to their high mobility, which could decrease the defect concentration, effectively.

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