Light Emission by Nanoporous GaN Produced by a Top-Down, Nonlithographical Nanopatterning

Temperature-dependent photoluminescence (PL) spectroscopy is carried out to probe radiative recombination and related light emission processes in two-dimensional periodic close-packed nanopore arrays in gallium nitride (np-GaN). The arrays were produced by nonlithographic nanopatterning of wurtzite GaN followed by a dry etching. The results of Raman spectroscopy point to a small relaxation of the compressive stress of ~0.24 GPa in nanoporous vs. bulk GaN. At ~300 K, the PL emission is induced by excitons and not free-carrier interband radiative recombinations. An evolution of the emission spectra with T is confirmed to be mainly a result of a decay of nonexcitonic PL emission and less of spectral shifts of the underlying PL bands. A switching of excitonic PL regime observed experimentally was analyzed within the exciton recombination-generation framework. The study provides new insights into the behaviors and physical mechanisms regulating light emission processes in np-GaN, critical to the development of nano-opto-electronic devices based on mesoscopic GaN.

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On the Origin of Light Emission in GaNxP1-x

MRS Proceedings ◽

10.1557/proc-722-k4.2 ◽

2002 ◽

Vol 722 ◽

Author(s):

I. A. Buyanova ◽

G. Yu. Rudko ◽

W. M. Chen ◽

H. P. Xin ◽

C. W. Tu

Keyword(s):

Light Emission ◽

Multiple Quantum Well ◽

The Other ◽

Multiple Quantum ◽

Optical Transitions ◽

Temperature Dependent ◽

Quantum Well Structures ◽

Pl Emission ◽

Temperature Dependent Photoluminescence ◽

Absorption Measurements

AbstractTemperature dependent photoluminescence (PL) and absorption measurements are employed to clarify mechanism for light emission in GaNP alloys with low (< 4.1) nitrogen content. The PL emission in GaNP epilayers and GaNP/GaP multiple quantum well structures is shown to be dominated by optical transitions within deep states likely related to N clusters. With increasing N composition these states are shown to become resonant with conduction band of the alloy and thus optically inactive, leading to the apparent red shift of the PL maximum position. On the other hand, band-to-band recombination in the alloy remains predominantly non-radiative presumably due to the presence of a large number of competing recombination channels.

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Temperature-dependent photoluminescence properties of porous fluorescent SiC

Scientific Reports ◽

10.1038/s41598-019-52871-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 5

Author(s):

Weifang Lu ◽

Abebe T. Tarekegne ◽

Yiyu Ou ◽

Satoshi Kamiyama ◽

Haiyan Ou

Keyword(s):

Surface Passivation ◽

Surface States ◽

Atomic Layer ◽

Emission Peak ◽

Photoelectron Spectra ◽

Porous Structures ◽

Temperature Dependent ◽

Time Resolved ◽

Pl Emission ◽

Temperature Dependent Photoluminescence

Abstract A comprehensive study of surface passivation effect on porous fluorescent silicon carbide (SiC) was carried out to elucidate the luminescence properties by temperature dependent photoluminescence (PL) measurement. The porous structures were prepared using an anodic oxidation etching method and passivated by atomic layer deposited (ALD) Al2O3 films. An impressive enhancement of PL intensity was observed in porous SiC with ALD Al2O3, especially at low temperatures. At temperatures below 150 K, two prominent PL emission peaks located at 517 nm and 650 nm were observed. The broad emission peak at 517 nm was attributed to originate from the surface states in the porous structures, which was supported by X-ray photoelectron spectra characterization. The emission peak at 650 nm is due to donor-acceptor-pairs (DAP) recombination via nitrogen donors and boron-related double D-centers in fluorescent SiC substrates. The results of the present work suggest that the ALD Al2O3 films can effectively suppress the non-radiative recombination for the porous structures on fluorescent SiC. In addition, we provide the evidence based on the low-temperature time-resolved PL that the mechanism behind the PL emission in porous structures is mainly related to the transitions via surface states.

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Effects of valence band tails on the blue and red spectral shifts observed in the temperature-dependent photoluminescence of InN

physica status solidi (b) ◽

10.1002/pssb.201248552 ◽

2013 ◽

Vol 250 (8) ◽

pp. 1572-1577 ◽

Cited By ~ 2

Author(s):

Ian P. Seetoh ◽

Chew Beng Soh ◽

Eugene A. Fitzgerald ◽

Soo Jin Chua

Keyword(s):

Valence Band ◽

Temperature Dependent ◽

Spectral Shifts ◽

Temperature Dependent Photoluminescence ◽

Band Tails

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Focused Ion Beam Irradiation Induced Damages on CMOS and Bipolar Technologies

10.31399/asm.cp.istfa1998p0049 ◽

1998 ◽

Author(s):

J. Benbrik ◽

G. Rolland ◽

P. Perdu ◽

B. Benteo ◽

M. Casari ◽

...

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Electronic Devices ◽

Complete Characterization ◽

Bipolar Transistors ◽

Ion Beam Irradiation ◽

Physical Mechanisms ◽

Dc Characteristics ◽

Electrical Degradation ◽

Physical Phenomena

Abstract Focused Ion Beam is commonly used for IC repairs and modifications. However, FIB operation may also induce a damaging impact which can takes place far from the working area due to the charge-up phenomenon. A complete characterization joined to an in-depth understanding of the physical phenomena arising from FIB irradiation is therefore necessary to take into account spurious FIB induced effects and to enhance the success of FIB modifications. In this paper, we present the effects of FIB irradiation on the electrical DC performances of different electronic devices such as nMOS and pMOS transistors, CMOS inverters, PN junctions and bipolar transistors. From the observed behavior of the DC characteristics evolution of the devices, some suggestions about physical mechanisms inducing the electrical degradation are proposed.

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Combustion Synthesis and Temperature Dependent Photoluminescence of Nanocrystalline Y2Zr2O7: Eu3+

Journal of Inorganic Materials ◽

10.3724/sp.j.1077.2009.00239 ◽

2009 ◽

Vol 24 (2) ◽

pp. 239-242 ◽

Cited By ~ 1

Author(s):

Dian-Yuan WANG ◽

Qing-Kai WANG ◽

Zhang-Yong CHANG ◽

Yan-Yan GUO ◽

Xing-Hua WU

Keyword(s):

Combustion Synthesis ◽

Temperature Dependent ◽

Temperature Dependent Photoluminescence

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Temperature-dependent photoluminescence from MEH-PPV and MEH-OPPV containing oxadiazole in the main chain

Applied Physics A ◽

10.1007/s00339-006-3601-5 ◽

2006 ◽

Vol 84 (1-2) ◽

pp. 203-206 ◽

Cited By ~ 17

Author(s):

F. Kong ◽

X.L. Wu ◽

G.S. Huang ◽

R.K. Yuan ◽

C.Z. Yang ◽

...

Keyword(s):

Main Chain ◽

Temperature Dependent ◽

Temperature Dependent Photoluminescence

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Temperature-Dependent Photoluminescence of ZnO Thin Films Grown on Off-Axis SiC Substrates by APMOCVD

Materials ◽

10.3390/ma14041035 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1035

Author(s):

Ivan Shtepliuk ◽

Volodymyr Khranovskyy ◽

Arsenii Ievtushenko ◽

Rositsa Yakimova

Keyword(s):

Optical Properties ◽

Structural Quality ◽

Organic Chemical ◽

Zno Films ◽

Vicinal Surfaces ◽

Temperature Dependent ◽

Step Flow ◽

Step Flow Growth ◽

First Time ◽

Temperature Dependent Photoluminescence

The growth of high-quality ZnO layers with optical properties congruent to those of bulk ZnO is still a great challenge. Here, for the first time, we systematically study the morphology and optical properties of ZnO layers grown on SiC substrates with off-cut angles ranging from 0° to 8° by using the atmospheric pressure meta–organic chemical vapor deposition (APMOCVD) technique. Morphology analysis revealed that the formation of the ZnO films on vicinal surfaces with small off-axis angles (1.4°–3.5°) follows the mixed growth mode: from one side, ZnO nucleation still occurs on wide (0001) terraces, but from another side, step-flow growth becomes more apparent with the off-cut angle increasing. We show for the first time that the off-cut angle of 8° provides conditions for step-flow growth of ZnO, resulting in highly improved growth morphology, respectively structural quality. Temperature-dependent photoluminescence (PL) measurements showed a strong dependence of the excitonic emission on the off-cut angle. The dependences of peak parameters for bound exciton and free exciton emissions on temperature were analyzed. The present results provide a correlation between the structural and optical properties of ZnO on vicinal surfaces and can be utilized for controllable ZnO heteroepitaxy on SiC toward device-quality ZnO epitaxial layers with potential applications in nano-optoelectronics.

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The thermal stability of FAPbBr3 nanocrystals from temperature-dependent photoluminescence and first-principles calculations

RSC Advances ◽

10.1039/d0ra07668f ◽

2020 ◽

Vol 10 (72) ◽

pp. 44373-44381

Author(s):

Xiaozhe Wang ◽

Qi Wang ◽

Zhijun Chai ◽

Wenzhi Wu

Keyword(s):

First Principles ◽

First Principle ◽

First Principles Calculations ◽

Temperature Dependent ◽

Time Resolved ◽

First Principle Calculations ◽

Steady State Time ◽

Time Resolved Photoluminescence ◽

Thermal Stability Of ◽

Temperature Dependent Photoluminescence

The thermal properties of FAPbBr3 perovskite nanocrystals (PNCs) is investigated by use of temperature-dependent steady-state/time-resolved photoluminescence and first-principle calculations.

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