scholarly journals Effect of localized UV irradiation on the crystallinity and electrical properties of dip-coated polythiophene thin films

RSC Advances ◽  
2020 ◽  
Vol 10 (56) ◽  
pp. 34130-34136
Author(s):  
So Young Park ◽  
Eun Hye Kwon ◽  
Yeong Don Park
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Uv Irradiation ◽  
Uv Light ◽  
P3ht Film ◽  
Enhanced Crystallinity

When the top part of the solution was irradiated with UV light, the dip-coated P3HT film showed enhanced crystallinity and electrical properties.

On the UV-light-induced Desorption/Adsorption Mechanism of Atmospheric Species in Solution-processed Zinc Oxide Thin Films

MRS Advances ◽  
2019 ◽  
Vol 4 (2) ◽  
pp. 111-117
Author(s):  
José Bruno Cantuária ◽  
Giovani Gozzi ◽  
Lucas Fugikawa Santos
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Electrical Properties ◽  
Uv Light ◽  
Atmospheric Oxygen ◽  
Low Cost ◽  
Environmental Parameters ◽  
Zno Films ◽  
Desorption Rate ◽  
Transparent Semiconductor

AbstractZinc oxide (ZnO) is a n-type transparent semiconductor which can be processed by low cost techniques (such as spray-pyrolysis and spin-coating) and can be applied as the active layer of thin-films transistors (TFTs). The electrical properties of ZnO films are strongly affected when the device is exposed to room conditions and/or UV-light, suggesting possible applications as UV or/and gas sensors. Atmospheric oxygen molecules adsorbed on ZnO surface act as charge traps, decreasing the material conductivity. The incidence of UV-light causes an increase of the material conductivity due to the photogeneration of electron-hole pairs via direct band-to-band transitions (classic photoconductivity process) and due to the desorption of oxygen molecules, which presents a relatively slower response and is a less understood mechanism. In the current paper, we study the influence of environmental parameters, such as temperature, humidity and UV-light intensity, on the electrical properties of spin-coated ZnO thin films to understand the role of the desorption mechanism on the photoconductivity process. The analysis of the device current vs. time curves shows the existence of two light-induced desorption mechanisms: i) one which increases the electrical conductivity of the ZnO film (desorption-like process) and ii) a second one which decreases the conductivity (adsorption-like process). A Plackett-Burman design of experiment (DOE) was used to study the influence of characterization factors like UV intensity, temperature and humidity on electrical parameters obtained from the experimental curves. We observed that the desorption-like process is a first order mechanism, exhibiting desorption rate proportional to n(t), where n(t) represents the adsorbate concentration as a function of the time, whereas the adsorption-like mechanism exhibits a desorption rate proportional to the forth power of n(t).

Novel Approach for Improving Interface Quality of 4H-SiC MOS Devices with UV Irradiation and Subsequent Thermal Annealing

2013 ◽  
Vol 740-742 ◽  
pp. 741-744 ◽  
Author(s):  
Heiji Watanabe ◽  
Daisuke Ikeguchi ◽  
Takashi Kirino ◽  
Shuhei Mitani ◽  
Yuki Nakano ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Thermal Annealing ◽  
Uv Irradiation ◽  
Uv Light ◽  
Interface State ◽  
State Density ◽  
Mos Devices ◽  
Novel Approach ◽  
Subsequent Thermal Annealing ◽  
Thermally Grown

We report on the harmful impact of ultraviolet (UV) light irradiation on thermally grown SiO2/4H-SiC(0001) structures and its use in subsequent thermal annealing for improving electrical properties of SiC-MOS devices. As we previously reported [1], significant UV-induced damage, such as positive flatband voltage shift and hysteresis in capacitance-voltage curves as well as increased interface state density, was observed for SiC-MOS devices with thermally grown oxides. Interestingly, the subsequent annealing of damaged SiO2/SiC samples resulted in superior electrical properties to those for untreated (fresh) devices. These findings imply that UV irradiation of the SiO2/SiC structure is effective for eliciting pre-existing carbon-related defects and transforming them into a simple configuration that can be easily passivated by thermal treatment.

scholarly journals UV irradiation effect on the electrical properties of Pb2MoO5 single crystal

2018 ◽  
Vol 26 (2) ◽  
pp. 63-66
Author(s):  
I. P. Volnyanskaya ◽  
M. P. Trubitsyn ◽  
D. M. Volnianskii ◽  
D. S. Bondar
Keyword(s):  
Electrical Properties ◽  
Single Crystal ◽  
Uv Irradiation ◽  
Room Temperature ◽  
Uv Light ◽  
Dipole Moments ◽  
Irradiation Effect ◽  
Deep Traps ◽  
Temperature Dependences ◽  
Ac Field

Electrical properties of Pb2MoO5 single crystal were studied in AC field (f=1 kHz) after irradiation with UV light (290 K). It was found that UV irradiation caused appearance of maximums on permittivity ε and conductivity σ temperature dependences, which were observed around 530 K. The anomalies of ε and σ vanished after annealing at 700 K and could be restored by subsequent UV irradiation performed at room temperature. The magnitude of ε and σ peaks increased for higher exposition time. Above 600 K conductivity σ was practically independent on irradiation. It is proposed that photoelectrons induced by UV light, are trapped by Mo located -within the oxygen tetrahedrons with vacancy VO in one of the vertexes. The dipole moments of (MoO3) groups reorient at VO hopping through the tetrahedron vertexes. Annealing at 700 K thermally decomposes (MoO3)- complexes. For T>600 K behavior of σ(T) is determined by conduction currents and nearly insensitive to UV irradiation. At high temperatures the photoelectrons do not contribute to conductivity since they are bound in (MoO3)- centers, recombine with holes or re-captured by more deep traps.

UV irradiation effects on the bonding structure and electrical properties of ultra low-k SiOC(–H) thin films for 45 nm technology node

2011 ◽  
Vol 11 (5) ◽  
pp. S109-S113 ◽  
Author(s):  
Chi Kyu Choi ◽  
Chang Young Kim ◽  
R. Navamathavan ◽  
Heang Seuk Lee ◽  
Jong-Kwan Woo ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Uv Irradiation ◽  
Irradiation Effects ◽  
Technology Node ◽  
Bonding Structure ◽  
Low K

scholarly journals Size Effect of Gold Nanoparticles on Optical and Electrical Properties of Au@TiO\(_2\) Nanocomposite Thin Films

2020 ◽  
Vol 31 (1) ◽  
Author(s):  
Long Duy Pham ◽  
Chi Ha Le ◽  
Oanh Thi Tu Nguyen ◽  
Chien Tran Dang ◽  
Tai Ngoc Ly ◽  
...  
Keyword(s):  
Thin Films ◽  
Gold Nanoparticles ◽  
Electrical Properties ◽  
Uv Light ◽  
Great Influence ◽  
Nanocomposite Films ◽  
Optical And Electrical Properties ◽  
Solar Simulator ◽  
Sem Images ◽  
20 Nm

This study focuses on the influence of gold nanoparticle sizes on optical and electrical properties of Au@TiO2 nanocomposite films. Here, the gold nanoparticles (AuNPs) of different sizes of 5 nm, 10 nm, 20 nm, 40 nm and 60 nm were dispersed onto nanoporous TiO2 thin films to form Au@TiO2 nanocomposite films. FE-SEM images and UV-vis absorption spectra show that AuNPs had good dispersion on the TiO2 films and all Au@TiO2 nanocomposite films exhibited a good surface plasmon resonance (SPR) with the resonance absorption peaks in the visible light region (about 550 nm). The effect of AuNPs on the films photoluminescence property was investigated using excited laser light of 325 nm wavelength at room temperature. The films electrical properties were studied from the change of the photocurrent under illumination of solar simulator and UV light source. The results show that the presence of gold nanoparticles has significantly improved the photocurrent of Au@TiO2 nanocomposite films and especially when AuNPs size was less than 20 nm. In addition, we also found that the photocurrent magnitude of the films with small AuNPs sizes (5 nm and 10 nm) under solar simulator light was 4 times larger than the one under UV light. These results indicate that AuNPs size had a great influence on the improvement of photocurrent in nanocomposite films.

scholarly journals Synthesis of Carvedilol–Organotin Complexes and Their Effects on Reducing Photodegradation of Poly(Vinyl Chloride)

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 500 ◽  
Author(s):  
Omar G. Mousa ◽  
Gamal A. El‐Hiti ◽  
Mohammed A. Baashen ◽  
Muna Bufaroosha ◽  
Ahmed Ahmed ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Vinyl Chloride ◽  
Uv Irradiation ◽  
Chemical Structure ◽  
Uv Light ◽  
Poly Vinyl Chloride ◽  
Pvc Film ◽  
Tin Complexes

Poly(vinyl chloride) (PVC) undergoes photodegradation induced by ultraviolet (UV) irradiation; therefore, for outdoor applications, its photostability should be enhanced through the use of additives. Several carvedilol tin complexes were synthesized, characterized and mixed with PVC to produce thin films. These films were irradiated at 25 °C with a UV light (λ = 313 nm) for up to 300 h. The reduction in weight and changes in chemical structure and surface morphology of the PVC films were monitored. The films containing synthesized complexes showed less undesirable changes than the pure PVC film. Organotin with a high content of aromatics was particularly efficient in inhibiting photodegradation of PVC. The carvedilol tin complexes both absorbed UV light and scavenged radicals, hydrochloride, and peroxides and, therefore, photostabilized PVC.

scholarly journals Multi-Level Evaluation of UV Action upon Vitamin D Enhanced, Silver Doped Hydroxyapatite Thin Films Deposited on Titanium Substrate

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 120
Author(s):  
Catalin Constantin Negrila ◽  
Daniela Predoi ◽  
Rodica V. Ghita ◽  
Simona Liliana Iconaru ◽  
Steluta Carmen Ciobanu ◽  
...  
Keyword(s):  
Thin Films ◽  
Uv Irradiation ◽  
Uv Light ◽  
Titanium Substrate ◽  
Degradation Process ◽  
Tissue Reconstruction ◽  
Multi Level ◽  
First Time ◽  
Vacuum Deposition Method ◽  
Ftir Investigation

Hydroxyapatite Ca10(PO4)6(OH)2 (HAp) is an important bioactive material for bone tissue reconstruction, due to its highly thermodynamic stability at a physiological pH without bio-resorption. In the present study, the Ag:HAp and the corresponding Ag:HAp + D3 thin films (~200 nm) coating were obtained by vacuum deposition method on Ti substrate. The obtained samples were exposed to different UV irradiation times, in order to investigate the UV light action upon thin films, before considering this method for the thin film’s decontamination. The effects of UV irradiation upon Ag:Hap + D3 are presented for the first time in the literature, marking a turning point for understanding the effect of UV light on composite biomaterial thin films. The UV irradiation induced an increase in the initial stages of surface roughness of Ag:HAp thin film, correlated with the modifications of XPS and FTIR signals. The characteristics of thin films measured by AFM (RMS) analysis corroborated with XPS and FTIR investigation highlighted a process of recovery of the thin film’s properties (e.g., RMS), suggesting a possible adaptation to UV irradiation. This process has been a stage to a more complicated UVA rapid degradation process. The antifungal assays demonstrated that all the investigated samples exhibited antifungal properties. Moreover, the cytotoxicity assays revealed that the HeLa cells morphology did not show any alterations after 24 h of incubation with the Ag:HAp and Ag:HAp + D3 thin films.

scholarly journals Monitoring the Photodegradation of PVC Thin Films Containing Schiff Base Using FTIR Spectroscopy

2019 ◽  
Vol 4 (1) ◽  
pp. 12-17
Author(s):  
Ali Hassan ◽  
Dina S. Ahmed ◽  
Riyadh Noaman ◽  
Emad Yousif
Keyword(s):  
Thin Films ◽  
Schiff Base ◽  
Light Intensity ◽  
Metal Complexes ◽  
Ftir Spectroscopy ◽  
Uv Irradiation ◽  
Infrared Spectra ◽  
Uv Light ◽  
Base Derivative

Metal complexes of Cu(II), Cd(II), Zn(II), Ni(II) and Sn(II) containing Schiff base derivative (L) as a ligand (ML2) utilized as additives to avoid PVC films photodegradation during UV irradiation (λmax= 313 at a light intensity = 7.75 × 10-7 einstein dm-3 sec-1). Irradiation of PVC films with UV light due to changes in infrared spectra.

Study on the Electrical Properties of Direct-Patternable SBT Films Formed by Photochemical Metal-Organic Deposition

2007 ◽  
Vol 544-545 ◽  
pp. 1061-1064
Author(s):  
Hyeong Ho Park ◽  
Hyung Ho Park ◽  
Ho Jung Chang ◽  
Hyeong Tag Jeon
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Grain Growth ◽  
Uv Irradiation ◽  
Remnant Polarization ◽  
Ferroelectric Properties ◽  
Surface Microstructure ◽  
Metal Organic ◽  
Metal Organic Deposition ◽  
Anneal Temperature

The ferroelectric properties of UV irradiated and non-irradiated SBT thin films using photosensitive starting precursors were investigated. The observation of surface microstructure showed that UV irradiation and increase in anneal temperature induced the grain growth of SBT. The measured remnant polarization values of UV irradiated and non-irradiated SBT films after anneal at 700oC were 5.8 and 4.7 )C/cm2 and after anneal at 750oC, the values were 10.8 and 9.3 )C/cm2, respectively.

Sign in / Sign up

Export Citation Format

Share Document