Volume 9, Issue 2 (10-2010)
Abstract
In this research, ac measurements of copper phthalocyanine thin film using aluminium electrodes are investigated in the frequency range 102 to 105 Hz and within the temperature range frequency and the capacitance and dissipation factor(loss tangent) decrease with increasing relative importance of the hopping model and band theory in describing the film condution with regard to the operating conditions. It was observed that the band theory is dominant at high frequencies and high temperatures, whereas hopping model is dominant at low frequencies. The energy gap of CuPc was determined using dc measurements.
Me Azimaraghi, Sn Riazi, Salar Porteamor,
Volume 14, Issue 3 (10-2014)
Abstract
In the present study, we investigate DC conduction mechanism of electron beam evaporated Bromoaluminium phthalocyanine (BrAlPc) thin films using aluminum and gold electrodes. The current-voltage characteristics of sandwich type device are evaluated for the temperature range 298-413K under dark conditions. It is observed that the current passing through the device is increased by increasing temperature at the same voltage in the range of 0-6v. It is found that at lower voltages about 0 to 2v, the current–voltage characteristics demonstrate Ohmic behavior, while the space charge limited current (SCLC) becomes apparent at higher voltages about 2 to 6v, which is restricted by single discrete trapping level. We obtained more than one linear region in the temperature dependence of electrical conductivity. Also, the values of charge carrier mobility and the activation energy of device are evaluated.
