In order to interpret well whether or not the organic or polymer interfacial layer is effective on performance of the conventional Au/n-Si (metal semiconductor [MS]) type Schottky barrier diodes (SBDs), in respect to ideality factor (n), leakage current, rectifying rate (RR), series and shunt resistances (R-s, R-sh) and surface states (N-ss) at room temperature, both Au/biphenyl-CoPc/n-Si (MPS1) and Au/OHSubs-ZnPc/n-Si (MPS2) type SBDs were fabricated. The electrical characteristics of these devices have been investigated and compared by using forward and reverse bias current-voltage (I-V) characteristics in the voltage range of (-4V)-(4V) for with and without (biphenyl-CoPc) and (OHSubs-ZnPc) interfacial layers at room temperature. The main electrical parameters of these diodes such as reverse saturation current (I-0), ideality factor (n), zero-bias barrier height (phi(B0)), RR, R-s and R-sh were found as 1.14x10(-5)A, 5.8, 0.6eV, 362, 44 and 15.9k for reference sample (MS), 7.05x10(-10)A, 3.8, 0.84eV, 2360, 115 and 270k for MPS1 and 2.16x10(-7)A, 4.8, 0.7eV, 3903, 62 and 242k for MPS2, respectively. It is clear that all of these parameters considerably change by using an organic interfacial layer. The energy density distribution profile of N-ss was found for each sample by taking into account the voltage dependence of effective barrier height (phi(e)) and ideality factor, and they were compared. Experimental results confirmed that the use of biphenyl-CoPc and OHSubs-ZnPc interfacial layer has led to an important increase in the performance of the conventional of MS type SBD. Copyright (c) 2015 John Wiley & Sons, Ltd.