Giant domain formation in Langmuir–Blodgett films based on Alkylammonium–Au(dmit) 2 salt

• Published in: Thin solid films 2008-03, Vol.516 (9), p.2518-2521
• Main Authors: Miura, Y.F., Hayashi, K., Kitao, M., Takagi, M., Matsui, H., Sugi, M.
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Giant domains; Langmuir-blodgett films; Langmuir–Blodgett film; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Materials science; Metal(dmit) 2 anion; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Uni-axial molecular arrangement
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2007.04.137

The crossed polarized-light microscopy has revealed that the as-deposited LB film of the 2C 14–Au(dmit) 2 salt consists of giant domains of several hundred microns, which have a uni-axial molecular arrangement. By the electrochemical oxidation, the giant domains disappear and smaller domains of 5–10 μm appear. According to the atomic force microscopy (AFM) observation, the as-deposited film consists of domains of several microns but it appears that the observed domains are fragments formed by cracks generated in much larger domains, as seen by the shapes. It is hypothesized that there exist giant domains at the air/water interface but cracks are made during the transfer process. Thus, the uni-axial molecular arrangement is kept over the macroscopic range. Considering the random potentials set up by grain boundaries and/or defects, fabrication of the crack-free LB film is considered to be indispensable for realizing metallic properties down to much lower temperatures and global superconductivity.