Modification by UV-light irradiation of the affinity for copper chemical vapour deposition of self-assembled monolayers of organosilanes on SiO2 substrates

2007 ◽  
Vol 201 (16-17) ◽  
pp. 7327-7338 ◽  
Author(s):  
N.G. Semaltianos
2005 ◽  
Vol 879 ◽  
Author(s):  
M. Wei ◽  
D. Zhi ◽  
J. L. MacManus-Driscoll

AbstractZnO, which exhibits a direct bandgap of 3.37 eV at room temperature with a large exciton binding energy of 60 meV,is of considerable technological importance because of its potential use in short-wavelength devices, such as ultraviolet (UV) light-emitting diodes and laser diodes. The fabrication and application of 1-D ZnO nanostructures has attracted considerable interest in recent years. In this work, we produced single crystal nanowires of zinc oxide using a novel self-seeded growth using ultrasonic spray assisted chemical vapour deposition, in which a nanocrystalline seed layer was first deposited onto a glass substrate and the nanowires subsequently grown using a different precursor concentration and substrate temperature. The diameter of the nanowires is in the range of 20-80 nm and the length of the wires is as long as 10 μm. The single crystal nature of the nanowires was revealed by high resolution transmission electron microscopy. The formation of liquid droplets due to the reducing atmosphere and the higher temperature during the nanowire growth was found to be the key step of the ZnO nanowire formation.


2008 ◽  
Vol 25 (2) ◽  
pp. 667-670 ◽  
Author(s):  
Li Lin ◽  
Liu Guo-Jun ◽  
Wang Xiao-Hua ◽  
Li Mei ◽  
Li Zhan-Guo ◽  
...  

2012 ◽  
Vol 1451 ◽  
pp. 179-184
Author(s):  
Cecilia Mattevi ◽  
Florian Colléaux ◽  
Hokwon Kim ◽  
Manish Chhowalla ◽  
Thomas D. Anthopoulos

ABSTRACTWe demonstrate low operating voltage (<|1.5| V) chemical vapour deposited (CVD) graphene transistors using solution processable organic self-assembled monolayers (SAMs) as nanodielectrics. The transistors show weak extrinsic doping, hysteresis-free operation, low gate-leakage current and good operating stability with bias-stress free characteristics. Most importantly we demonstrate that the Dirac potential can be finely tuned by modifying the molecular end-group of the SAMs without compromising the electrical characteristics of the transistors.


2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
Siti Hajar Othman ◽  
Suraya Abdul Rashid ◽  
Tinia Idaty Mohd Ghazi ◽  
Norhafizah Abdullah

Titanium dioxide (TiO2) nanoparticles were produced using chemical vapour deposition (CVD) at different deposition temperatures (300–700°C). All the samples were heat treated at their respective deposition temperatures and at a fixed temperature of 400°C. A scanning electron microscope (SEM), a transmission electron microscope (TEM), and X-ray diffraction (XRD) were used to characterize the nanoparticles in terms of size and crystallinity. The photocatalytic activity was investigated via degradation of methylene blue under UV light. The effects of post deposition heat treatment are discussed in terms of crystallinity, nanoparticle size as well as photocatalytic activity. Crystallinity was found to have a much larger impact on photocatalytic activity compared to nanoparticle size. Samples having a higher degree of crystallinity were more photocatalytically active despite being relatively larger in size. Surprisingly, the photocatalytic activity of the samples reduced when heat treated at temperatures lower than the deposition temperature despite showing an improvement in crystallinity.


2003 ◽  
Vol 02 (04n05) ◽  
pp. 239-244
Author(s):  
TIEN-TZU LIANG ◽  
HIROAKI AZEHARA ◽  
TAKAO ISHIDA ◽  
WATARU MIZUTANI ◽  
HIROSHI TOKUMOTO

Oligo(para-phenylene-vinylene)-methanethiol of trimer and dimer have been synthesized to prepare monolayers onto Au(111). The trimer diluted in dichloromethane glows with a brilliant blue fluorescence when excited with UV light (365 nm). The absorption and emission spectra of the dimer diluted in CH 2 Cl 2 show a blue shift. The molecular level morphologies of the monolayers prepared on gold surfaces were probed by scanning tunneling microscopy or atomic force microscopy (AFM). The dimer is entire trans isomer, which formed highly ordered self-assembled monolayers (SAMs) on Au. The trimer is a mixture of cis–trans isomers, and did not form ordered monolayers on Au. However, the trimer molecules could be embedded in dodecanethiol SAM, and showed higher conductance than oligo(para-phenylene) molecules characterized using a conductive AFM.


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