Temperature dependence of the electrical and interface states of the Sn/Rhodamine-101/p-Si Schottky structures

In this paper, the current–voltage (I–V) characteristics of Sn/Rhodamine-101/p-Si/Al contacts have been measured at temperatures ranging from 80 to 400 K at 30 K intervals. The nonpolymeric organic compound Rhodamine-101 (Rh101) film on a p-type Si substrate has been formed by means of the evaporation process and the Sn/Rhodamine-101/Si contacts have been fabricated. The current–voltage characteristics of the diode show rectifying behaviour consistent with a potential barrier formed at the interface. The obtained I–V barrier heights (Φb) were in the range of 0.208–0.940 eV with ideality factors (n) of 14.37–2.72. The high values of ideality factor (n) may be ascribed to decrease the exponentially increase rate in current due to space-charge injection into Rh101 thin film at higher voltage. Temperature dependence of the energy distribution of interface states density profile was determined from the forward bias I–V characteristics. It is shown that organic semiconductor layer (Rhodamine-101) controls electrical charge transport properties of Sn/p-Si Schottky structure by excluding effects.