Abstract: The I-V characteristics and isothermal decay currents (IDC) of α-CuPc/PVK. have been studied. Ohm's law was observed below the field of 1.2×10⁴ V/cm. At higher voltage,both of dark/photo conductions became non-Ohmic,lg(I/V) were directly proportional to V^1/2,the non-Ohmic conductivity observed could be represented by: σ = σ0exp [1.5×10^-4×E^1/2KT] ,and the coefficient 1.5×10^-4 eV/(V/cm)^1/2 met the value required by Poole-Frenkel effect. The data of IDC were analyzed after the simple relaxation treatment by plotting lg[I(1)] vs. t. The temperture dependence of relaxation time fitted Arrhenius equation from which activation energy E_α could be obatained. The field dependence of E_α appeared close to the Poole-Frenkel effect too. We tried to apply Garofano's expression to the relaxation time,and calculated the trapped carrier density and the attempt-to-escape frequency.

Key words: copper-phthalocyanine, voltage-current characteristic, isothermal decay-current, Poole-Frenkel effect