Effects of Channel Dimension and Doping Concentration of Source and Drain Contacts on GNRFET Performance

Silicon ◽  
2020 ◽  
Author(s):  
Tahereh Radsar ◽  
Hassan Khalesi ◽  
Vahid Ghods ◽  
Alireza Izadbakhsh
Keyword(s):  
Doping Concentration ◽  
Channel Dimension

Experimental Studies of New GaAs Metal/Insulator/p-n+Switches Using Low Temperature Oxide

2002 ◽  
Vol 25 (3) ◽  
pp. 233-237
Author(s):  
K. F. Yarn
Keyword(s):  
Low Temperature ◽  
Negative Differential Resistance ◽  
Doping Concentration ◽  
Experimental Studies ◽  
Differential Resistance ◽  
Switching Behavior ◽  
Metal Insulator ◽  
Turn On ◽  
Temperature Oxide ◽  
Phase Chemical

First observation of switching behavior is reported in GaAs metal-insulator-p-n+structure, where the thin insulator is grown at low temperature by a liquid phase chemical-enhanced oxide (LPECO) with a thickness of 100 Å. A significant S-shaped negative differential resistance (NDR) is shown to occur that originates from the regenerative feedback in a tunnel metal/insulator/semiconductor (MIS) interface andp-n+junction. The influence of epitaxial doping concentration on the switching and holding voltages is investigated. The switching voltages are found to be decreased when increasing the epitaxial doping concentration, while the holding voltages are almost kept constant. A high turn-off/turn-on resistance ratio up to105has been obtained.

Impact of co-doping concentration in copolymer network liquid crystals

2019 ◽  
Vol 46 (10) ◽  
pp. 1485-1493 ◽  
Author(s):  
Fatemeh Jahanbakhsh ◽  
Alexander Lorenz
Keyword(s):  
Liquid Crystals ◽  
Doping Concentration ◽  
Co Doping ◽  
Copolymer Network

scholarly journals Numerical Investigation of Graphene as a Back Surface Field Layer on the Performance of Cadmium Telluride Solar Cell

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3275
Author(s):  
Devendra KC ◽  
Deb Kumar Shah ◽  
M. Shaheer Akhtar ◽  
Mira Park ◽  
Chong Yeal Kim ◽  
...  
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Doping Concentration ◽  
Carrier Lifetime ◽  
Short Circuit ◽  
Back Surface ◽  
Back Surface Field ◽  
Cdte Solar Cell ◽  
Cdte Solar Cells ◽  
Surface Field

This paper numerically explores the possibility of ultrathin layering and high efficiency of graphene as a back surface field (BSF) based on a CdTe solar cell by Personal computer one-dimensional (PC1D) simulation. CdTe solar cells have been characterized and studied by varying the carrier lifetime, doping concentration, thickness, and bandgap of the graphene layer. With simulation results, the highest short-circuit current (Isc = 2.09 A), power conversion efficiency (h = 15%), and quantum efficiency (QE ~ 85%) were achieved at a carrier lifetime of 1 × 103 ms and a doping concentration of 1 × 1017 cm−3 of graphene as a BSF layer-based CdTe solar cell. The thickness of the graphene BSF layer (1 mm) was proven the ultrathin, optimal, and obtainable for the fabrication of high-performance CdTe solar cells, confirming the suitability of graphene material as a BSF. This simulation confirmed that a CdTe solar cell with the proposed graphene as the BSF layer might be highly efficient with optimized parameters for fabrication.

scholarly journals Cobalt-doped bioceramic scaffolds fabricated by 3D printing show enhanced osteogenic and angiogenic properties for bone repair

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Jungang Li ◽  
Chaoqian Zhao ◽  
Chun Liu ◽  
Zhenyu Wang ◽  
Zeming Ling ◽  
...  
Keyword(s):  
Compressive Strength ◽  
3D Printing ◽  
Bone Regeneration ◽  
Doping Concentration ◽  
Artificial Bone ◽  
Bone Defect Repair ◽  
Co Doping ◽  
Defect Repair ◽  
Co Doped

Abstract Background The bone regeneration of artificial bone grafts is still in need of a breakthrough to improve the processes of bone defect repair. Artificial bone grafts should be modified to enable angiogenesis and thus improve osteogenesis. We have previously revealed that crystalline Ca10Li(PO4)7 (CLP) possesses higher compressive strength and better biocompatibility than that of pure beta-tricalcium phosphate (β-TCP). In this work, we explored the possibility of cobalt (Co), known for mimicking hypoxia, doped into CLP to promote osteogenesis and angiogenesis. Methods We designed and manufactured porous scaffolds by doping CLP with various concentrations of Co (0, 0.1, 0.25, 0.5, and 1 mol%) and using 3D printing techniques. The crystal phase, surface morphology, compressive strength, in vitro degradation, and mineralization properties of Co-doped and -undoped CLP scaffolds were investigated. Next, we investigated the biocompatibility and effects of Co-doped and -undoped samples on osteogenic and angiogenic properties in vitro and on bone regeneration in rat cranium defects. Results With increasing Co-doping level, the compressive strength of Co-doped CLP scaffolds decreased in comparison with that of undoped CLP scaffolds, especially when the Co-doping concentration increased to 1 mol%. Co-doped CLP scaffolds possessed excellent degradation properties compared with those of undoped CLP scaffolds. The (0.1, 0.25, 0.5 mol%) Co-doped CLP scaffolds had mineralization properties similar to those of undoped CLP scaffolds, whereas the 1 mol% Co-doped CLP scaffolds shown no mineralization changes. Furthermore, compared with undoped scaffolds, Co-doped CLP scaffolds possessed excellent biocompatibility and prominent osteogenic and angiogenic properties in vitro, notably when the doping concentration was 0.25 mol%. After 8 weeks of implantation, 0.25 mol% Co-doped scaffolds had markedly enhanced bone regeneration at the defect site compared with that of the undoped scaffold. Conclusion In summary, CLP doped with 0.25 mol% Co2+ ions is a prospective method to enhance osteogenic and angiogenic properties, thus promoting bone regeneration in bone defect repair.

scholarly journals Crystallization, Luminescence and Cytocompatibility of Hexagonal Calcium Doped Terbium Phosphate Hydrate Nanoparticles

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 322
Author(s):  
Jaime Gómez-Morales ◽  
Raquel Fernández-Penas ◽  
Ismael Romero-Castillo ◽  
Cristóbal Verdugo-Escamilla ◽  
Duane Choquesillo-Lazarte ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Doping Concentration ◽  
Hydration Number ◽  
Maturation Time ◽  
Human Carcinoma ◽  
Inductively Coupled ◽  
Carcinoma Cell Lines ◽  
Carbonate Solutions ◽  
Human Carcinoma Cell ◽  
Calcium Doped

Luminescent lanthanide-containing biocompatible nanosystems represent promising candidates as nanoplatforms for bioimaging applications. Herein, citrate-functionalized calcium-doped terbium phosphate hydrate nanophosphors of the rhabdophane type were prepared at different synthesis times and different Ca2+/Tb3+ ratios by a bioinspired crystallization method consisting of thermal decomplexing of Ca2+/Tb3+/citrate/phosphate/carbonate solutions. Nanoparticles were characterized by XRD, TEM, SEM, HR-TEM, FTIR, Raman, Thermogravimetry, inductively coupled plasma spectroscopy, thermoanalysis, dynamic light scattering, electrophoretic mobility, and fluorescence spectroscopy. They displayed ill-defined isometric morphologies with sizes ≤50 nm, hydration number n ~ 0.9, tailored Ca2+ content (0.42–8.11 wt%), and long luminescent lifetimes (800–2600 µs). Their relative luminescence intensities in solid state are neither affected by Ca2+, citrate content, nor by maturation time for Ca2+ doping concentration in solution below 0.07 M Ca2+. Only at this doping concentration does the maturation time strongly affect this property, decreasing it. In aqueous suspensions, neither pH nor ionic strength nor temperature affect their luminescence properties. All the nanoparticles displayed high cytocompatibility on two human carcinoma cell lines and cell viability correlated positively with the amount of doping Ca2+. Thus, these nanocrystals represent promising new luminescent nanoprobes for potential biomedical applications and, if coupled with targeting and therapeutic moieties, they could be effective tools for theranostics.

scholarly journals Optimization of Sb2S3 Nanocrystal Concentrations in P3HT: PCBM Layers to Improve the Performance of Polymer Solar Cells

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2152
Author(s):  
E. M. Mkawi ◽  
Y. Al-Hadeethi ◽  
R. S. Bazuhair ◽  
A. S. Yousef ◽  
E. Shalaan ◽  
...  
Keyword(s):  
Solar Cells ◽  
Doping Concentration ◽  
Polymer Solar Cells ◽  
Energy Levels ◽  
Acid Methyl Ester ◽  
Visible Absorption ◽  
Block Polymer ◽  
Coating Method ◽  
Electronic Parameters ◽  
P Type

In this study, polymer solar cells were synthesized by adding Sb2S3 nanocrystals (NCs) to thin blended films with polymer poly(3-hexylthiophene)(P3HT) and [6,6]-phenyl-C61-butyric-acid-methyl-ester (PCBM) as the p-type material prepared via the spin-coating method. The purpose of this study is to investigate the dependence of polymer solar cells’ performance on the concentration of Sb2S3 nanocrystals. The effect of the Sb2S3 nanocrystal concentrations (0.01, 0.02, 0.03, and 0.04 mg/mL) in the polymer’s active layer was determined using different characterization techniques. X-ray diffraction (XRD) displayed doped ratio dependences of P3HT crystallite orientations of P3HT crystallites inside a block polymer film. Introducing Sb2S3 NCs increased the light harvesting and regulated the energy levels, improving the electronic parameters. Considerable photoluminescence quenching was observed due to additional excited electron pathways through the Sb2S3 NCs. A UV–visible absorption spectra measurement showed the relationship between the optoelectronic properties and improved surface morphology, and this enhancement was detected by a red shift in the absorption spectrum. The absorber layer’s doping concentration played a definitive role in improving the device’s performance. Using a 0.04 mg/mL doping concentration, a solar cell device with a glass /ITO/PEDOT:PSS/P3HT-PCBM: Sb2S3:NC/MoO3/Ag structure achieved a maximum power conversion efficiency of 2.72%. These Sb2S3 NCs obtained by solvothermal fabrication blended with a P3HT: PCBM polymer, would pave the way for a more effective design of organic photovoltaic devices.

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