Dielectric and ac conduction properties of zinc phthalocyanine (ZnPc) thin films

School of Semiconductor and Chemical Engineering, BK21 Center for Future Energy Materials and Devices, Chonbuk National University, Jeonju 561-756, South Korea
Journal of Applied Physics (Impact Factor: 2.21). 03/2007; DOI: 10.1063/1.2435805
Source: IEEE Xplore

ABSTRACT The dielectric responses of zinc phthalocyanine (ZnPc) thin films, deposited using the vacuum evaporation technique, were studied as functions of frequency and temperature. The conductivity of the deposited films decreases with increase in temperature. The dielectric studies clearly indicated that the Debye type of polarization exists in these films. The relaxation phenomena have been confirmed from the Cole-Cole plot. The relaxation times have been evaluated from the plot and were found to be (τa) 0.0137 and 0.0106 s at 303 and 403 K , respectively. The prevailing conduction mechanism in ZnPc films, under an ac field, was found to be electronic hopping. The activation energy was evaluated from the Arrhenius plot and was found to be 1.28 eV . Based on the structure, and with the help of quantum mechanics calculations, the electronic structure and behavior that upheld our experimental results were identified.

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