Electrical conduction and photodiode properties of Au/Feq3/p-Si/al hybrid heterostructure

Thin films of iron tris(8-hydroxyquinoline) (Feq3) are prepared on p-Si substrates by thermal deposition under high vacuum. The current-voltage (I-V) curves of Au/Feq3/p-Si/Al heterojunction are recorded as a function of temperature range from 303 to 383 K at 20 K interval. The device shows rectification behavior, with room temperature ideality factor (n) and barrier height (phi) values of 2.30 and 0.81 eV, respectively. The temperature dependence of phi and n is explained in terms of barrier inhomogeneity, in which the homogenous phi value is estimated as 0.97 eV. The conduction mechanisms of the diode are determined and related parameters are evaluated The series resistance of the diode is estimated as a function of temperature. Up on illuminating the diode, the reverse current of the diode increases with increasing the impinging light intensity, from which the photosensitivity and photoconduction are determined.