High hardness and low dielectric constant thin films with oriented urea oligomers by physical vapor deposition

Oligomers of undecylurea (OUA11) thin films with a high crystallinity, surface hardness, perpendicular orientation, and low dielectric constant were fabricated by physical vapor deposition. The thin films were composed of single OUA11, which has a relatively high molecular weight (Mw: 2500, Mn: 1200...

Full description

Saved in:
Bibliographic Details
Published in:Journal of materials science 2019-02, Vol.54 (3), p.2483-2492
Main Authors: Morimoto, Masahiro, Fukutomi, Tatsuya, Koshiba, Yasuko, Ishida, Kenji
Format: Article
Language:English
Subjects:
Bonding strength
Characterization and Evaluation of Materials
Chemistry and Materials Science
Classical Mechanics
Crystal structure
Crystallinity
Crystallography and Scattering Methods
Dielectric properties
Dipoles
Electrical properties
Electronic materials
Energy Materials
Frequency ranges
Hardness
Hardness tests
Hydrogen bonds
Materials Science
Molecular structure
Molecular weight
Oligomers
Permittivity
Physical vapor deposition
Polymer Sciences
Protective coatings
Solid Mechanics
Spin coating
Substrates
Surface hardness
Thermal decomposition
Thin films
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Oligomers of undecylurea (OUA11) thin films with a high crystallinity, surface hardness, perpendicular orientation, and low dielectric constant were fabricated by physical vapor deposition. The thin films were composed of single OUA11, which has a relatively high molecular weight (Mw: 2500, Mn: 1200) and could be vapor-deposited without thermal decomposition. These films had a much higher crystallinity and a high surface hardness level of 9H in the pencil hardness test. The dielectric constant of the OUA11 films is estimated to be 2.1–2.3 in the frequency range of 1 Hz–0.1 MHz, which is lower than that of typical low dielectric constant (low-k) materials. These physical and electrical properties are caused by the unique structure with the molecular dipoles-oriented parallel to the electrodes on the substrate and the strong intermolecular hydrogen bonds. The unique structure could not be observed with spin-coating and is specific to the vapor-deposited films. We expect that the OUA11 films with a high hardness and a low dielectric constant can be used not only as protective coatings but also as electronic materials.
ISSN:0022-2461
1573-4803
DOI:10.1007/s10853-018-3000-2