Self Organization in Thin Films of a Substituted Perylene Imide with a Twisted Aromatic Core

ABSTRACTThe aromatic core of perylene bisimides can be twisted by chemical substitution with chlorine in the bay-position. An example for this strategy is 1,6,7,10-tetra-chloro-N,N'-dimethyl-perylene-tetracarboxylic-bisimide, Cl4MePTCDI. This twisting leads to a decrease in directed intermolecular interactions, which causes a decrease in the electronic coupling of the molecules, interesting to be investigated in thin films of this molecular semiconductor. An amorphous solid phase was formed by physical vapor deposition. This amorphous phase showed the tendency to crystallize under ambient conditions as apparent von optical microscopy at the films. The crystallized phase was investigated by atomic force microscopy AFM and optical methods, where a formation of weak excimers was found.

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Optical and Morphological Studies of Thermally Evaporated PTCDI-C8 Thin Films for Organic Solar Cell Applications

International Journal of Photoenergy ◽

10.1155/2013/205105 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 9

Author(s):

Ronak Rahimi ◽

V. Narang ◽

D. Korakakis

Keyword(s):

Thin Films ◽

Silicon Substrates ◽

High Electron ◽

Ambient Conditions ◽

Force Microscopy ◽

Morphological Studies ◽

Atomic Force ◽

Organic Semiconductor Devices ◽

Thermal Evaporator ◽

High Degree

PTCDI-C8 due to its relatively high photosensitivity and high electron mobility has attracted much attention in organic semiconductor devices. In this work, thin films of PTCDI-C8 with different thicknesses were deposited on silicon substrates with native silicon dioxide using a vacuum thermal evaporator. Several material characterization techniques have been utilized to evaluate the structure, morphology, and optical properties of these films. Their optical constants (refractive index and extinction coefficient) have been extracted from the spectroscopic ellipsometry (SE). X-ray reflectivity (XRR) and atomic force microscopy (AFM) were employed to determine the morphology and structure as well as the thickness and roughness of the PTCDI-C8 thin films. These films revealed a high degree of structural ordering within the layers. All the experimental measurements were performed under ambient conditions. PTCDI-C8 films have shown to endure ambient condition which allows pots-deposition characterization.

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Imaging Water Thin Films in Ambient Conditions Using Atomic Force Microscopy

Materials ◽

10.3390/ma9030182 ◽

2016 ◽

Vol 9 (3) ◽

pp. 182 ◽

Cited By ~ 15

Author(s):

Sergio Santos ◽

Albert Verdaguer

Keyword(s):

Thin Films ◽

Atomic Force Microscopy ◽

Ambient Conditions ◽

Force Microscopy ◽

Atomic Force

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Structure and morphology in thin films of perfluorinated copper phthalocyanine grown on alkali halide surfaces (001)

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424612501064 ◽

2012 ◽

Vol 16 (07n08) ◽

pp. 977-984 ◽

Cited By ~ 4

Author(s):

Enno Lorenz ◽

Christopher Keil ◽

Derck Schlettwein

Keyword(s):

Thin Films ◽

Physical Vapor Deposition ◽

Copper Phthalocyanine ◽

Alkali Halides ◽

Square Lattice ◽

Force Microscopy ◽

Lattice Constants ◽

Atomic Force ◽

Vis Spectroscopy ◽

Ordered Phases

Thin films from the monolayer range to the thickness of 40 nm of the perfluorinated copper phthalocyanine (F16PcCu) were prepared by physical vapor deposition on freshly cleaved (001) faces of the alkali halides NaCl , KCl and KBr . The different lattice constants of the substrates provided sufficient difference to trigger the growth of differently ordered phases of F16PcCu . Electron diffraction, Atomic Force Microscopy and UV-vis spectroscopy were used to characterize the structure for F16PcCu monolayers and for films of increasing average film thickness towards bulk films. A square lattice of flat-lying F16PcCu is proposed for the first monolayers. In the bulk films, phases already described for F16PcCu on other substrates were formed, but also a new phase was discovered.

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FABRICATION OF CARBON THIN FILMS BY PULSED LASER DEPOSITION IN DIFFERENT AMBIENT ENVIRONMENTS

Jurnal Teknologi ◽

10.11113/jt.v78.7506 ◽

2016 ◽

Vol 78 (3) ◽

Author(s):

Mohamad Helmi Abd Mubin ◽

Muhammad Sufi Roslan ◽

Syed Zuhaib Haider Rizvi ◽

Kashif Chaudhary ◽

Suzairi Daud ◽

...

Keyword(s):

Thin Films ◽

Peak Height ◽

Maximum Height ◽

Ambient Conditions ◽

Graphite Target ◽

Force Microscopy ◽

Atomic Force ◽

Average Maximum ◽

Spacing Ratio ◽

Carbon Thin Films

In this work, carbon thin films are grown in different background environments (Air, Helium and Argon) at different pressures (60, 160, 500 and 1000 mbar) by ablating the graphite target with Nd:YAG laser of wavelength of 1064 nm, pulse energy of 740 mJ and pulse rate of 6 ns. 10,000 laser shots are used to ablate graphite target under different ambient conditions. Grown thin films are analyzed by Atomic Force Microscopy (AFM) to measure thickness, roughness average, maximum profile peak height, average maximum height of profile and spacing ratio of the surface. The obtained results show that the roughness average, thickness of film, maximum profile peak height, average maximum height of profile and spacing ratio of thin films decreases with increase in ambient pressuresand shows highest value at low pressure (160 mbar) in helium environment as compared with air and argon.

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Synthesis and characterization of polyimide thin films obtained by thermal evaporation and solid state reaction

Materials Science-Poland ◽

10.1515/msp-2016-0029 ◽

2016 ◽

Vol 34 (1) ◽

pp. 132-136 ◽

Cited By ~ 3

Author(s):

Ikram Atta Al-Ajaj ◽

Aseel A. Kareem

Keyword(s):

Thin Films ◽

Solid State ◽

Solid State Reaction ◽

Physical Vapor Deposition ◽

Amic Acid ◽

Surface Topology ◽

Polyimide Films ◽

Force Microscopy ◽

Atomic Force ◽

Ft Ir

AbstractIn this research polyimide films were prepared by physical vapor deposition (PVD), using solid state reaction of pyromellitic dianhydride (PMDA) and p-phenylene diamine (PDA) to form poly(amic acid) (PAA) films. The resultant films were converted to polyimide by thermal treatment, usually below 300 °C. For this study, a FT-IR spectrometer has been used to measure the effect of imidization temperature on the chemical structure of the vapor-deposited thin films of aromatic PI. When temperature increased, an increase in all absorption peaks was observed. This suggests that residual PAA monomers continued to be converted into PI. The surface topology of the PI films obtained at imidization temperatures of 150, 200, 250 °C for 1 hour was further examined by using AFM atomic force microscopy. It can be clearly seen that the surface became rougher with increasing imidization temperature. The thermal stability of polyimide was also studied by using thermogravimetric analysis (TGA).

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