We use polarization-resolved and temperature-dependent photoluminescence of single zincblende (ZB) (cubic) wurtzite (WZ) (hexagonal) InP nanowires to probe differences in selection rules bandgaps between these two semiconductor nanostructures. The WZ exhibit a bandgap 80meV higher energy than the ZB nanowires. temperature dependence PL is similar but not identical for find that strong polarization parallel nanowire axis, while polarized emission perpendicular axis. This behavior interpreted...

Abstract There has been much interest in developing a thin-film solar cell because it is lightweight and flexible. The GaAs top contender the market that high power conversion efficiency (PCE) compared to of other cells. are two common structures for cell: n (emitter)-on-p (base) p-on-n. former performs better due its collection electron diffusion length p-type base region longer than hole n-type region. However, limited fabricate highly efficient n-on-p single-junction thin film on flexible...

We report the results of a study optical gain properties binary blend films regioregular poly(3-hexylthiophene) (RR-P3HT) and poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT). Efficient is observed in 10–20 wt. % RR-P3HT composition range can be tuned to ∼650 nm window utilised for polymer fibre data-communications, with maximum ∼50 cm−1. At higher P3HT fractions, thresholds increase substantially, consistent concomitant improvement photocharge generation. Distributed feed back lasers...

We present a new semi‐insulating carbon‐doped GaN/undoped GaN multi‐layered buffer structure for AlGaN/GaN heterojunction field effect transistors, which drastically suppresses current collapse in MISHFET with improving the on‐current performance of device but without degrading breakdown characteristic. It is believed that spatial compensation between layers not only makes layer very highly resistive, also prevents electrons from 2DEG channel being captured into deep traps layer, maintains...

Abstract Radial junction solar cells with vertically aligned wire arrays have been widely studied to improve the power conversion efficiency. In this work, we report first Ge nanopillar cell. Nanopillar are selectively patterned on p-type (100) substrates using nanosphere lithography and deep reactive ion etching processes. Nanoscale radial planar junctions realized by an n-type emitter layer which is epitaxially grown MOCVD isobutylgermane. situ epitaxial surface passivation employed InGaP...

We have proposed a new semi-insulating GaN buffer layer, which consists of multiple carbon-doped and undoped layer. The layer showed sufficiently good characteristics, attributed to the depletion effect between layers, even though thickness in periodic structure was designed be very thin minimize total carbon incorporation into AlGaN/AlN/GaN heterostructure grown on exhibited much better electrical structural properties than that conventional thick confirmed by Hall measurement, x-ray...

Flexible thin film (In)GaAs solar cells are grown by metalorganic chemical vapor deposition on GaAs substrates and transferred to 30 μm thick Au foil internal stress-assisted epitaxial lift-off processes. The stress is induced replacing the cell epi-layers from In0.015Ga0.985As, which has a slightly larger lattice constant. compressive strained layer thickness was varied 0 4.5 investigate influence of time. etching time in process reduced 36 4 h employing GaAs/In0.015Ga0.985As heterojunction...

Dilute-nitride-antimonide materials grown by metalorganic vapor phase epitaxy (MOVPE) with bandgap energies of 1.25 eV have been integrated into solar cell structures employing a Ge bottom on substrate. Single homo- and heterojunction cells narrow GaAsSbN (E g ~ eV) are normally lattice-matched GaAs substrate, using MOVPE. Homojunction were realized material low carbon background concentration Si doping to form p/n junction. External quantum efficiency measurements in the range (870 nm-1000...

Ultrathin Ge single‐junction (1J) solar cells transferred onto a flexible substrate are envisioned to open up novel lattice‐matched thin‐film InGaP/(In)GaAs/Ge tandem cell for enabling highly efficient, low‐cost, and light‐weight devices. The ultrathin 1J structures epitaxially grown GaAs via low‐pressure metal–organic chemical vapor deposition system using an isobutylgermane metalorganic source as precursor. A simple fast epitaxial lift‐off method allows the epi transfer substrates, by...

SiC dry etching process for formation of a trenched-gate structure in trench metal-oxide-semiconductor field-effect-transistors employing bottom protection p-well (BPW) has been investigated. SF6/O2/Ar based inductively-coupled-plasma reactive-ion-etching were utilized with various variations parameters, such as bias power, ICP kind gas species, working pressure and temperature. The effects parameters on profiles analyzed by cross-sectional scanning electron microscope profilometer to...

Conical frustums with quasihexagonal nanostructures are fabricated on an InGaP window layer of single junction GaAs solar cells using a polystyrene nanosphere lithography technique followed by anisotropic etching processes. The optical and photovoltaic characteristics the conical frustum nanostructured investigated. Reflectance is significantly reduced in wide range wavelengths compared to that planar sample. measured reflectance reduction attributed gradual change refractive index layer. An...

, respectively. In this structure, the Eu atoms are situated at center of 18-vertexFedorov polyhedra made Zn and atoms, where 4 d site is preferentially occupied by e siteis randomly mixed atoms. Theoretical investigations using tight-binding linear muffin-tin orbital (TB-LMTO) method provide rationale for observed preferences suggest potentiallywider homogeneity range than experimentally established EuZn

Low background carbon concentration InGaAsN (Eg ∼ 1.18 eV), lattice-matched on a GaAs substrate, was grown at high temperatures (∼600 °C) using metalorganic vapor phase epitaxy. This material used as an alternative to the middle cell in triple-junction InGaP/GaAs/Ge solar cells. The low (∼5 × 1016 cm−3) and increased depletion region width of significantly improves performance over that found with dilute-nitride cells lower growth (∼525 °C). device active yielded short-circuit current...

We have investigated the impacts of Sb incorporation on microstructural, optical, electrical, and carrier dynamics properties bulk InGaAsSbN films in a comparative study InGaAsN materials grown by metal-organic vapor phase epitaxy (MOVPE). These were at relatively high temperature 600 °C annealed 800 for 30 min. Transmission electron microscopy studies indicate compositional structural homogeneity films. Low-temperature time-resolved photoluminescence measurements MOVPE-grown film show...