Properties of conductive polymer films deposited by infrared laser ablation

• Published in: Applied surface science 2007-05, Vol.253 (15), p.6430-6434
• Main Authors: Johnson, S.L., Park, H.K., Haglund, R.F.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conducting polymers; Cross-disciplinary physics: materials science; rheology; Electrical properties of specific thin films; Electron and ion emission by liquids and solids; impact phenomena; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Free-electron devices; Impact phenomena (including electron spectra and sputtering); Infrared laser; Intense particle beams and radiation sources; Laser deposition; Laser-beam impact phenomena; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; PEDOT:PSS; Physics; Physics of gases, plasmas and electric discharges; Physics of plasmas and electric discharges; Polymers; organic compounds; Resonant vibrational excitation; Thin film deposition
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2007.01.084

Thin films of the conducting polymer poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (PEDOT:PSS) were deposited by resonant infrared laser vapor deposition (RIR-LVD). The PEDOT:PSS was frozen in various matrix solutions and deposited using a tunable, mid-infrared free-electron laser (FEL). The films so produced exhibited morphologies and conductivities that were highly dependent on the solvent matrix and laser irradiation wavelength used. When deposited from a native solution (1.3% by weight in water), as in matrix-assisted pulsed laser evaporation (MAPLE), films were rough and electrically insulating. When the matrix included other organic “co-matrices” that were doped into the solution prior to freezing, however, the resulting films were smooth and exhibited good electrical conductivity (0.2 S/cm), but only when irradiated at certain wavelengths. These results highlight the importance of the matrix/solute and matrix/laser interactions in the ablation process.