Fabrication and electrical properties of organic-on-inorganic Schottky devices

Abstract

In this paper, we fabricated an Al/new fuchsin/p-Si organic–inorganic (OI) Schottkydiode structure by direct evaporation of an organic compound solution on a p-Sisemiconductor wafer. A direct optical band gap energy value of the new fuchsinorganic film on a glass substrate was obtained as 1.95 eV. Current–voltage(I–V) andcapacitance–voltage (C–V) measurements of the OI device were carried out at room temperature. From theI–V characteristics, it was seen that the Al/new fuchsin/p-Si contacts showed goodrectifying behavior. An ideality factor value of 1.47 and a barrier height (BH) value of0.75 eV for the Al/new fuchsin/p-Si contact were determined from the forward biasI–V characteristics. A barrier height value of 0.78 eV was obtained from the capacitance–voltage(C–V) characteristics. It has been seen that the BH value of 0.75 eV obtained for the Al/newfuchsin/p-Si contact is significantly larger than that of conventional Al/p-Si Schottkymetal–semiconductor (MS) diodes. Thus, modification of the interfacial potential barrierfor Al/p-Si diodes has been achieved using a thin interlayer of the new fuchsin organicsemiconductor; this has been ascribed to the fact that the new fuchsin interlayer increasesthe effective barrier height because of the interface dipole induced by passivation of theorganic layer.