scholarly journals Germanium Doping to Improve Carrier Mobility in CdO Films

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
A. A. Dakhel
Keyword(s):  
Carrier Mobility ◽  
Near Infrared ◽  
Transparent Conducting Oxide ◽  
Cadmium Oxide ◽  
Infrared Light ◽  
X Ray Diffraction ◽  
Low Resistivity ◽  
High Carrier Mobility ◽  
Good Transparency ◽  
Spectral Photometry

This investigation addresses the structural, optical, and electrical properties of germanium incorporated cadmium oxide (CdO : Ge) thin films. The focus was on the improvement in carrier mobility to achieve high transparency for near-infrared light and low resistivity at the same time. The properties were studied using X-ray diffraction, SEM, spectral photometry, and Hall measurements. All CdO : Ge films were polycrystalline with high texture orientation along [111] direction. It was observed that it is possible to control the carrier concentration () and mobility () with Ge-incorporation level. The mobility could be improved to a highest value of  cm2/V·s with Ge doping of 0.25 wt% while maintaining the electrical resistivity as low as  Ω·cm and good transparency % in the NIR spectral region. The results of the present work proved to select Ge as dopant to achieve high carrier mobility with low resistivity for application in transparent conducting oxide (TCO) field. Generally, the properties found make CdO : Ge films particularly interesting for the application in optoelectronic devices like thin-film solar cells.

Ultra-sensitive near-infrared graphene photodetectors with nanopillar antennas

Nanoscale ◽  
2017 ◽  
Vol 9 (44) ◽  
pp. 17459-17464 ◽  
Author(s):  
Yu Liu ◽  
Wen Huang ◽  
Tianxun Gong ◽  
Yue Su ◽  
Hua Zhang ◽  
...  
Keyword(s):  
Absorption Spectrum ◽  
Carrier Mobility ◽  
Near Infrared ◽  
Optoelectronic Devices ◽  
Broad Absorption ◽  
High Carrier Mobility ◽  
High Carrier

Graphene has been demonstrated as a candidate for optoelectronic devices due to its broad absorption spectrum and ultra-high carrier mobility.

Influence of Sputtering Power on the Structure, Optical and Electric Properties of Cu3N Films

2015 ◽  
Vol 814 ◽  
pp. 596-600 ◽  
Author(s):  
Li Na Chen ◽  
Jin Feng Leng ◽  
Zhong Xi Yang ◽  
Zhi Chao Meng ◽  
Bin Sun
Keyword(s):  
Near Infrared ◽  
Optical Band Gap ◽  
Infrared Light ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sputtering Power ◽  
Deposition Power ◽  
Higher Power ◽  
Uv Visible ◽  
Peak Value

The Cu3N films were deposited successfully by reactive direct current magnetron sputtering, the films were comprehensively and systematically characterized by X-ray diffraction analyzer (XRD), UV-Visible spectrophotometer, four-probe resistance tester and other instruments. Results showed that under low deposition power (80W~100W), crystal orientation increased, which is attributed to higher energy under higher power. When sputtering power exceeded the value, excessive energy led to anti-sputtering hindering the process of further nucleation and growth of films. The transmittance of the films deposited under 100W reached the peak value of 78% on the scope of near-infrared light, and optical band gap (Eg) of 1.35ev. The resistivity of Cu3N films increased from 9.68×102Ω.cm to 2.12×103Ω.cm with increasing in sputtering power up to 100W.

Synthesis and photoelectric properties of SnSe films through selenization of evaporated Sn-metal films

2021 ◽  
pp. 2150382
Author(s):  
Shun Wang ◽  
Honglie Shen ◽  
Shusong Cui ◽  
Yufang Li
Keyword(s):  
Near Infrared ◽  
Metal Films ◽  
Electron Beam Evaporation ◽  
Infrared Light ◽  
X Ray Diffraction ◽  
X Ray ◽  
Response Characteristics ◽  
Photoelectric Properties ◽  
Pure Phase ◽  
Large Application

Sn precursor layer was evaporated on a glass substrate by an electron-beam evaporation method and followed by selenization using Se powder. SnSe film was successfully prepared by adjusting the selenization temperature and selenization time. The phase, microstructure and optical properties of the SnSe films were studied by X-ray diffraction, Raman spectroscopy, Scanning Electron Microscopy, and UV-Vis-NIR spectrophotometer. The results demonstrated that the pure phase polycrystalline SnSe films with a band gap of 0.93 eV could be prepared by selenizing at 450[Formula: see text]C for 60 min. Under the irradiation of a 980 nm laser with a power of 2 mW/cm2, photoelectric response characteristics of the SnSe films were tested, and the response time and recovery time of the prepared film were 62 ms and 80 ms, respectively, indicating that the SnSe film had a large application prospect in near-infrared light detection.

scholarly journals Solution-processed near-infrared Cu(In,Ga)(S,Se)2 photodetectors with enhanced chalcopyrite crystallization and bandgap grading structure via potassium incorporation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joo-Hyun Kim ◽  
Hyemi Han ◽  
Min Kyu Kim ◽  
Jongtae Ahn ◽  
Do Kyung Hwang ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Grain Growth ◽  
Carrier Mobility ◽  
Near Infrared ◽  
Low Cost ◽  
Charge Carrier Mobility ◽  
Infrared Region ◽  
Infrared Light ◽  
Large Area ◽  
Solution Processed

AbstractAlthough solution-processed Cu(In,Ga)(S,Se)2 (CIGS) absorber layers can potentially enable the low-cost and large-area production of highly stable electronic devices, they have rarely been applied in photodetector applications. In this work, we present a near-infrared photodetector functioning at 980 nm based on solution-processed CIGS with a potassium-induced bandgap grading structure and chalcopyrite grain growth. The incorporation of potassium in the CIGS film promotes Se uptake in the bulk of the film during the chalcogenization process, resulting in a bandgap grading structure with a wide space charge region that allows improved light absorption in the near-infrared region and charge carrier separation. Also, increasing the Se penetration in the potassium-incorporated CIGS film leads to the enhancement of chalcopyrite crystalline grain growth, increasing charge carrier mobility. Under the reverse bias condition, associated with hole tunneling from the ZnO interlayer, the increasing carrier mobility of potassium-incorporated CIGS photodetector improved photosensitivity and particularly external quantum efficiency more than 100% at low light intensity. The responsivity and detectivity of the potassium-incorporated CIGS photodetector reach 1.87 A W−1 and 6.45 $$\times$$ ×  1010 Jones, respectively, and the − 3 dB bandwidth of the device extends to 10.5 kHz under 980 nm near-infrared light.

Photo-Electrical Properties of Trilayer MoSe2 Nanoflakes

NANO ◽  
2016 ◽  
Vol 11 (07) ◽  
pp. 1650082 ◽  
Author(s):  
Yang Hang ◽  
Qi Li ◽  
Wei Luo ◽  
Yanlan He ◽  
Xueao Zhang ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Carrier Mobility ◽  
Field Effect Transistor ◽  
Near Infrared ◽  
High Detection Rate ◽  
Infrared Wavelength ◽  
High Carrier Mobility ◽  
High Carrier ◽  
Photo Response ◽  
Effect Transistor

The photo-electrical properties of trilayer MoSe2 nanoflakes, fabricated by mechanical exfoliation, were systematically studied in this paper. The trilayer MoSe2 nanoflakes are n-type and possess a high gate modulation (On/Off ratio is larger than 10[Formula: see text] and a relatively high carrier mobility (1.79[Formula: see text]cm[Formula: see text]. The field effect transistor (FET) device of MoSe2 shows sensitive photo response, high photoresponsivity ([Formula: see text][Formula: see text]mA/W), quick response time ([Formula: see text][Formula: see text]ms), high external quantum efficiency ([Formula: see text] and high detection rate ([Formula: see text] for red and near-infrared wavelength. These results showed that the device based on few-layer MoSe2 nanoflakes exhibited good photo-electrical properties, which might open a new way to develop few-layer MoSe2-based material in the application of FETs and optoelectronics.

SUPERCRITICAL SOLVOTHERMAL SYNTHESIS AND NEAR-INFRARED ABSORBING PROPERTIES OF CsxWO3

2012 ◽  
Vol 05 (02) ◽  
pp. 1260001 ◽  
Author(s):  
CHONGSHEN GUO ◽  
SHU YIN ◽  
YUNFANG HUANG ◽  
QIANG DONG ◽  
HUIHUI LI ◽  
...  
Keyword(s):  
Near Infrared ◽  
Visible Region ◽  
Local Heat ◽  
Particle Size Analysis ◽  
Infrared Light ◽  
Size Analysis ◽  
Mixed Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nir Light

Cs x WO 3 nanoparticles in the range of 20–50 nm have been successfully synthesized by the supercritical solvothermal approach, where after dissolving WCl6 and CsOH in a mixed solution of water, ethanol and oleic acid, the solution was heated at 300°C. The products were characterized by X-ray diffraction, TEM, HR-TEM, EDS, laser particle size analysis and thermographic measurements. Cs x WO 3 nanoparticles showed the high transparency in the visible region, excellent shielding performance of the near-infrared light and limited reflectance of light in the range of 200–2700 nm, indicating the strong absorption of NIR light on the nanosized Cs x WO 3. Cs x WO 3 nanoparticles also exhibited quick conversion of photo-energy to local heat.

scholarly journals Photothermal Sensing of Nano-Devices Made of Graphene Materials

Sensors ◽  
2020 ◽  
Vol 20 (13) ◽  
pp. 3671
Author(s):  
Xiwen Lu ◽  
Lijun Yang ◽  
Zhan Yang
Keyword(s):  
Light Absorption ◽  
Carrier Mobility ◽  
Near Infrared ◽  
High Efficiency ◽  
Infrared Light ◽  
Thermal Heating ◽  
Electronic Components ◽  
Terahertz Band ◽  
Photoelectric Properties ◽  
Different Temperatures

Graphene is widely used as the basic materials of nano optical devices and sensors on account of its special structures and excellent photoelectric properties. Graphene is considered as an ideal material for photodetectors because of its ultra-wide absorption spectrum from the ultraviolet to the terahertz band, ultrahigh carrier mobility and ultrafast photoreaction speed. In this study, a photothermal nano-device was made using graphene that was transferred to an electrode using an all-dry viscoelastic stamping method. The nano-device has the advantages of simplicity, high efficiency and instant measurement. This nano-device was used to measure the light absorption of graphene, and the calculated light absorption rate of graphene is basically consistent with previous research results. Experiments on irradiation at different wavelengths and thermal heating at different temperatures show that the nano-device has an excellent response to near-infrared and mid-infrared light. The conclusions provide an experimental basis for the research, design and fabrication of nano-devices, and this device can provide an effective method for detecting light and temperature in areas such as electronic components and solar cells.

scholarly journals Silicon Meet Graphene for a New Family of Near-Infrared Schottky Photodetectors

2019 ◽  
Author(s):  
Maurizio Casalino
Keyword(s):  
Carrier Mobility ◽  
Near Infrared ◽  
Strong Light ◽  
Broadband Absorption ◽  
New Family ◽  
High Carrier Mobility ◽  
Light Matter Interaction ◽  
High Carrier ◽  
Schottky Junctions

In recent years graphene has attracted much interest due to its unique properties of flexibility, strong light-matter interaction, high carrier mobility and broadband absorption. In addition, graphene can be deposited on many substrates including silicon with which is able to form Schottky junctions opening the path to the realization of near-infrared silicon photodetectors based on the internal photoemission effect where graphene play the role of the metal. In this work, we review the very recent progress of the near-infrared photodetectors based on Schottky junctions involving graphene. This new family of device promises to overcome the limitations of the Schottky photodetectors based on metals showing the potentialities to compare favorably with germanium photodetectors currently employed in silicon photonics.

scholarly journals Study on catalytic properties of graphene/molybdenum sulfide under near-infrared light irradiation

2022 ◽  
Vol 5 (1) ◽  
pp. 16
Author(s):  
Huan Zhang ◽  
Shouqing Liu
Keyword(s):  
Hybrid Material ◽  
Degradation Rate ◽  
Near Infrared ◽  
Ph Value ◽  
Catalytic Efficiency ◽  
Molybdenum Sulfide ◽  
Infrared Light ◽  
Diffraction Spectrum ◽  
X Ray Diffraction ◽  
Transmission Electron

Graphene/MoS2 hybrid material was prepared by the hydrothermal method. The hybrid material was characterized by X-ray diffraction spectrum, Raman spectra, transmission electron microscope and UV-vis-NIRS. It was used as a near-infrared photocatalyst to catalyze and degrade Rhodamine B (RhB). The results showed that when the concentration of the RhB solution was 50.0 mg·L–1, the pH value of the solution was 7, the volume of the solution was 50.0 mL, the amount of G/MoS2 catalyst was 0.05 g and near-infrared radiation was carried out for 3 h, the degradation rate of RhB in the 50 mL solution reached 96.5%. When MoS2 was used as the photocatalyst, the degradation rate of RhB was only 75.5%. After 5 times of recycling, the catalytic efficiency of the hybrid photocatalyst was still more than 90%, indicating that the catalyst is very stable.

Fluorescent proteins for in vivo imaging, where's the biliverdin?

2020 ◽  
Vol 48 (6) ◽  
pp. 2657-2667
Author(s):  
Felipe Montecinos-Franjola ◽  
John Y. Lin ◽  
Erik A. Rodriguez
Keyword(s):  
Hydrogen Peroxide ◽  
In Vivo Imaging ◽  
Near Infrared ◽  
Fluorescent Protein ◽  
Fluorescent Proteins ◽  
Fluorescent Imaging ◽  
Infrared Light ◽  
Red Fluorescent Protein ◽  
Color Palette

Noninvasive fluorescent imaging requires far-red and near-infrared fluorescent proteins for deeper imaging. Near-infrared light penetrates biological tissue with blood vessels due to low absorbance, scattering, and reflection of light and has a greater signal-to-noise due to less autofluorescence. Far-red and near-infrared fluorescent proteins absorb light >600 nm to expand the color palette for imaging multiple biosensors and noninvasive in vivo imaging. The ideal fluorescent proteins are bright, photobleach minimally, express well in the desired cells, do not oligomerize, and generate or incorporate exogenous fluorophores efficiently. Coral-derived red fluorescent proteins require oxygen for fluorophore formation and release two hydrogen peroxide molecules. New fluorescent proteins based on phytochrome and phycobiliproteins use biliverdin IXα as fluorophores, do not require oxygen for maturation to image anaerobic organisms and tumor core, and do not generate hydrogen peroxide. The small Ultra-Red Fluorescent Protein (smURFP) was evolved from a cyanobacterial phycobiliprotein to covalently attach biliverdin as an exogenous fluorophore. The small Ultra-Red Fluorescent Protein is biophysically as bright as the enhanced green fluorescent protein, is exceptionally photostable, used for biosensor development, and visible in living mice. Novel applications of smURFP include in vitro protein diagnostics with attomolar (10−18 M) sensitivity, encapsulation in viral particles, and fluorescent protein nanoparticles. However, the availability of biliverdin limits the fluorescence of biliverdin-attaching fluorescent proteins; hence, extra biliverdin is needed to enhance brightness. New methods for improved biliverdin bioavailability are necessary to develop improved bright far-red and near-infrared fluorescent proteins for noninvasive imaging in vivo.

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