Morphology-Dependent Optical Energy Band Gap in Copper- and Manganese- Phthalocyanine Thin Films.

ORAL

Abstract

Metallo-phthalocyanines thin films have been used widely in applications, such as electronic and photonic devices, organic photovoltaic devices, and gas sensors. Copper phthalocyanine (CuPc) and manganese phthalocyanine (MnPc) thin films have been deposited on clean glass substrates by using thermal evaporation at several deposition temperatures to modify the crystal growth. Generally, electrical, and optical properties of CuPc and MnPc thin films depend on the morphology, which includes the grain size distribution (size, shape, and the orientation of stacked molecules), and film surface roughness. The energy band gap is estimated from the optical spectrum of the transmission data and found to vary with deposition temperature. The fundamental energy band gap of MnPc thin films increases for higher deposition temperatures. It has one energy band gap near 3.6 eV, which is in the Q-band region, whereas CuPc thin films have two energy band gaps in both the Soret band region and Q-band region. At low deposition temperatures, CuPc films have gaps at 1.71(2) eV, and 3.05(5) eV. But for higher deposition temperatures, the energy gap decreases to 1.64 eV and 2.93 eV. Consequently, the energy band gap in the Q-band is higher for MnPc than for CuPc.

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Authors

  • Anh Nguyen

    California State University, Long Beach

  • Ethan Anderes

    UC Davis, Lawrence Berkeley National Lab - ALS, National Institute of Standards and Technology - NCNR, Univ of California - Davis, University of California, Davis, California State University, Long Beach, University of California, Irvine, University of California, Merced, UC Merced, U Central Florida, Paul Scherrer Institute, Paul Scherrer Institute in Switzerland, Hartnell Comm Coll, University of Michigan, University of Nevada, Reno, National Security Technologies LLC, Livermore, California, Humboldt State University, Stanford University, San Diego State Univ, Institute of Mathematical Problems of Biology, Eindhoven University of Technology, University Of Nevada Reno, Univ of Nevada - Reno, University of Chicago, Physics Department of the University of Nevada, Reno, NV, USA, Institute for Academic Initiatives, PPC and Graduate School of Engineering, Osaka University, Joint Institute for High Temperatures, PPC and Graduate School of Engineering, Osaka University, Institute for Academic Initiatives, Joint Institute for High Temperatures, National Institute of Standards and Technology, Gaithersburg, MD, Department of Physics, UC Davis, Department of Physics & Astronomy, Univeristy of California Irvine, 92697, Department of Chemistry and of Physics, Univeristy of California Irvine, 92697, Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel 76100, Einstein Centre for Local-Realistic Physics, Cal State Long Beach, University of nevada, Reno, Nicolaus Copernicus University, Torun, Poland, University of Maryland, CERN, Univ of California, Davis

  • Thomas Gredig

    California State University, Long Beach