Electrical behaviour of thermally evaporated chloroaluminium phthalocyanine

Abstract

The a.c. electrical behaviour of thermally evaporated thin films of chloroaluminium phthalocyanine sandwich devices have been studied in the frequency range 10 4 -4 × 10 6 Hz and in the temperature range 295-430 K. In the high-frequency region the a.c. conductivity is proportional to ω s . Capacitance and dissipation factors (tan δ) decrease with increasing frequency and increase with increasing temperature. Such behaviour was found to be in good agreement with the previous results that we found for lead phthalocyanine. The results obtained show the relative importance of the hopping model and band theory in describing the film conduction with regard to the operating conditions. The hopping model is dominant at low temperatures and high frequencies, whereas the band theory is dominant at high temperatures and low frequencies.