Crystal growth of photovoltaic polycrystalline Si1-xGex by die-casting growth

ABSTRACTCoin-shaped multicrystalline Si1-xGex crystals were grown using a Brigdman method combined with die-casting growth. Si1-xGex alloy is known as a candidate material for producing Auger generation, which creates more than one electron/hole pair per absorbed photon. Since Si1-xGex alloy shows a complete series of solid solutions, precipitating crystals with a certain composition of silicon or germanium by conventional selective growth methods is burdensome. Using die-casting combined with Bridgman growth brought about Si1-xGex precipitation in a form completely different from that predicted by the Si-Ge phase diagram. By combining this growth with subsequent heat treatment of the precipitated Si1-xGex sample, Si1-xGex (x= 0.5 ± 3 %) could be obtained. Indirect band-gap energy was estimated by measuring room-temperature optical absorption coefficient of the grown samples.

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Hydrogen Collision Model of The Staebler-Wronski Effect: Microscopics and Kinetics

MRS Proceedings ◽

10.1557/proc-507-709 ◽

1998 ◽

Vol 507 ◽

Cited By ~ 3

Author(s):

Howard M. Branz

Keyword(s):

Room Temperature ◽

Pair Creation ◽

Hole Pair ◽

Dangling Bond ◽

Electron Hole ◽

Spin Resonance ◽

Electron Hole Pair ◽

Staebler Wronski Effect ◽

Hydrogenated Amorphous ◽

Creation Rate

ABSTRACTA new microscopic and kinetic model of light-induced metastability in hydrogenated amorphous silicon (a-Si:H) is described. Recombination and trapping of photoinduced carriers excite hydrogen from deep Si-H bonds into a mobile configuration, leaving a dangling bond (DB) defect at the site of excitation. Normally, mobile H are recaptured at DB defects and no metastability or net DB production results. However, when two mobile H collide, they form a metastable two-hydrogen complex and leave two spatially-uncorrelated Staebler-Wronski DBs. Thermal and light-induced annealing occur when mobile H are excited from the metastable two-H complex; they diffuse and are recaptured to DBs. The microscopic model is entirely compatible with electron-spin-resonance results showing neither DB-DB nor DB-H spatial correlation of the light-induced DBs. The model leads to new differential equations describing the evolution of the mobile H and DB densities. These equation equations explain the observed room-temperature Ndb∼G2/3t1/3 dependence of DB creation upon the electron-hole pair creation rate (G) and time. The model also accounts for both t1/3-kinetics at 4.2K and t1/2-kinetics under laser-pulse soaking. Neither of these results can be explained within the prevailing electron-hole pair recombination model.

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Femtosecond Dynamics of Nonequilibrium Correlated Electron-Hole Pair Distributions in Room-Temperature GaAs Multiple Quantum Well Structures

Ultrafast Phenomena IV - Springer Series in Chemical Physics ◽

10.1007/978-3-642-82378-7_44 ◽

1984 ◽

pp. 162-165 ◽

Cited By ~ 2

Author(s):

W. H. Knox ◽

R. L. Fork ◽

M. C. Downer ◽

D. A. B. Miller ◽

D. S. Chemla ◽

...

Keyword(s):

Quantum Well ◽

Room Temperature ◽

Multiple Quantum Well ◽

Hole Pair ◽

Multiple Quantum ◽

Electron Hole ◽

Quantum Well Structures ◽

Femtosecond Dynamics ◽

Correlated Electron ◽

Electron Hole Pair

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CMOS compatible Si/SiO2 multilayers for Light Emitting Diodes

MRS Proceedings ◽

10.1557/proc-638-f18.5.1 ◽

2000 ◽

Vol 638 ◽

Cited By ~ 2

Author(s):

Z. Gaburro ◽

L. Pavesi ◽

G. Pucker ◽

P. Bellutti

Keyword(s):

Quantum Confinement ◽

Room Temperature ◽

Blackbody Radiation ◽

Single Type ◽

Hot Electron ◽

Electron Hole ◽

Light Emitting ◽

Electron Relaxation ◽

Electron Hole Pair ◽

Plasmon Polaritons

AbstractWe report photoluminescence and electroluminescence at room temperature in diodes based on Si/SiO2 multilayers. The multilayers are fabricated by alternating Si and SiO2 layers, whose thickness is, respectively, 2 and 5 nanometers. In photoluminescence, a single band is observed, centered at 800 nm, which is due to electron-hole pair recombination under quantum confinement. On the other hand, in electroluminescence, two bands are reported. The first band is in the infrared spectrum, and is blackbody radiation. The second band is visible, and is originated by relaxation of a single type of electrical carrier (electrons), as suggested by a fast decay time (less than 0.1 µs). Possible mechanisms can be hot-electron relaxation or coupling with surface plasmon-polaritons.

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Low-Dimensional CsPbBr3@CoBr2 Super-Nanowire Structure for Perovskite/PMMA Composite with Highly Blue Emissive Performance

Crystals ◽

10.3390/cryst11121564 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1564

Author(s):

Xuan-Viet Pham ◽

Ba-Duc Tran ◽

Duy-Cuong Nguyen ◽

Tu Nguyen ◽

Minh-Vuong Nguyen ◽

...

Keyword(s):

Room Temperature ◽

Carrier Lifetime ◽

Electron Hole ◽

One Pot ◽

Transmission Electron ◽

Electron Hole Pair ◽

Low Dimensional ◽

Color Rendering ◽

Excellent Color ◽

Nanowire Structure

In this study, low-dimensional CsPbBr3@CoBr2 super-nanowire (SNW) structures were synthesized via a one-pot heating strategy for highly blue emissions. By introducing CoBr2 to CsPbBr3 precursors, the shape of perovskite nanocrystals was changed from cuboids to a super-nanowire structure, as revealed through a transmission electron microscope. SNWs were formed from stacked segments of nano-plates (lateral dimension of 10–12 nm and thickness of ~2.5 nm) with lengths of several microns. The fabricated sample absorbs light at a wavelength of <450 nm, and it is emitted at a wavelength of 475 nm. It also has a radiant flux conversion efficiency of up to 85% when stimulated by a 430 nm LED light source. The average decay time of up to 80 µs indicates that they effectively prevent the recombination of electron–hole pair. The optical performance still remains over 65% when the ambient temperature is up to 120 °C compared with that under room temperature. The excellent color purity, optical quantum efficiency, long carrier lifetime, and thermal stability make CsPbBr3@CoBr2 SNWs highly promising for a range of photolumicescence applications, such as a high color rendering index lighting and transparent blue emissive screen.

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The Doping and Characterization of Erbium-Implanted Gan

MRS Proceedings ◽

10.1557/proc-482-579 ◽

1997 ◽

Vol 482 ◽

Cited By ~ 6

Author(s):

J. T. Torvik ◽

R. J. Feuerstein ◽

C. H. Qiu ◽

J. I. Pankove ◽

F. Namavar

Keyword(s):

Room Temperature ◽

Impact Excitation ◽

Electron Impact Excitation ◽

Device Performance ◽

Hot Electron ◽

Electron Hole ◽

Excitation Process ◽

Electron Hole Pair ◽

Single Exponential

AbstractStrong room temperature Er-related photoluminescence (PL) and electroluminescence (EL) at 1539 nm was observed from Er and 0 implanted n-type GaN. Good device performance requires that the Er-related excitation and emission processes be efficient. Single exponential PL and EL time decays with l/e lifetimes of 2.33 ms and 1.74 ms indicates highly efficient radiative process. The Er excitation process in GaN was studied by comparing the efficiency of direct Erabsorption, electron-hole pair recombination, and hot electron (impact) excitation. The strongest Er luminescence and the lowest pump power was found using impact excitation.

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Normal Bands in Surface-Enhanced Raman Scattering (SERS) and Their Relation to the Electron-Hole Pair Excitation Background in SERS

Israel Journal of Chemistry ◽

10.1560/t812-4131-8246-4863 ◽

2006 ◽

Vol 46 (3) ◽

pp. 307-315 ◽

Cited By ~ 1

Author(s):

Andreas Otto ◽

Walter Akemann ◽

Annemarie Pucci

Keyword(s):

Raman Scattering ◽

Surface Enhanced Raman Scattering ◽

Hole Pair ◽

Electron Hole ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Electron Hole Pair ◽

Enhanced Raman Scattering ◽

Pair Excitation

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Ti3C2-MXene/Bismuth Ferrite Nanohybrids for Efficient Degradation of Organic Dye and Colorless Pollutant

10.26434/chemrxiv.8192375.v1 ◽

2019 ◽

Author(s):

Ayesha Tariq ◽

M. Abdullah Iqbal ◽

S. Irfan Ali ◽

Muhammad Z. Iqbal ◽

Deji Akinwande ◽

...

Keyword(s):

Surface Area ◽

Low Cost ◽

Bismuth Ferrite ◽

Organic Dye ◽

Two Dimensional ◽

Electron Hole ◽

Photocatalytic Application ◽

Electron Hole Pair ◽

Pair Generation ◽

Photocatalytic Applications

Nanohybrids, made up of Bismuth ferrites/Carbon allotropes, are extensively used in photocatalytic applications nowadays. Our work proposes a nanohybrid system composed of Bismuth ferrite nanoparticles with two-dimensional (2D) MXene sheets namely, the BiFeO3 (BFO)/Ti3C2 (MXene) nanohybrid for enhanced photocatalytic activity. We have fabricated the BFO/MXene nanohybrid using simple and low cost double solvent solvothermal method. The SEM and TEM images show that the BFO nanoparticles were attached onto the MXene surface and in the inter-layers of two-dimensional (2D) MXene sheets. The photocatalytic application is tested for the visible light irradiation which showed the highest efficiency among all pure-BFO based photocatalysts, i.e. 100% degradation in 42 min for organic dye (Congo Red) and colorless aqueous pollutant (acetophenone) in 150 min, respectively. The present BFO-based hybrid system exhibited the large surface area of 147 m2g-1measured via Brunauer-Emmett-Teller (BET) sorption-desorption technique, and is found to be largest among BFO and its derivatives. Also, the photoluminescence (PL) spectra indicate large electron-hole pair generation. Fast and efficient degradation of organic molecules is supported by both factors; larger surface area and lower electron-hole recombination rate. The BFO/MXene nanohybrid presented here is a highly efficient photocatalyst compared to other nanostructures based on pure BiFeO3 which makes it a promising candidate for many future applications.

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Electrical Invasiveness of Grinding and Polishing Silicon Integrated Circuits Down to 1 μm Remaining Silicon Thickness

ISTFA 2016: Conference Proceedings from the 42nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2016p0166 ◽

2016 ◽

Author(s):

Robert Chivas ◽

Scott Silverman ◽

Michael DiBattista ◽

Ulrike Kindereit

Keyword(s):

Integrated Circuits ◽

Failure Analysis ◽

Electron Hole ◽

Analysis Techniques ◽

Silicon Integrated Circuits ◽

Electron Hole Pair ◽

Pair Generation ◽

Silicon Thickness ◽

Performance Timing ◽

Grinding And Polishing

Abstract Anticipating the end of life for IR-based failure analysis techniques, a method of global backside preparation to ultra-thin remaining silicon thickness (RST) has been developed. When the remaining silicon is reduced, some redistribution of stress is expected, possibly altering the performance (timing) of integrated circuits in addition to electron-hole pair generation. In this work, a study of the electrical invasiveness due to grinding and polishing silicon integrated circuits to ultra-thin (< 5 um global, ~ 1 um local) remaining thickness is presented.

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