Barrier Parameters and Current Transport Characteristics of Ti/p-InP Schottky Junction Modified Using Orange G (OG) Organic Interlayer

A Ti/Orange G/p-InP metal/interlayer/semiconductor (MIS) junction has been prepared with Orange G (OG) organic layer by electron beam evaporation and spin coating processes. The electrical properties of Ti/p-InP metal/semiconductor (MS) and Ti/OG/p-InP MIS junctions have been analyzed based on current–voltage (I–V) and capacitance–voltage (C–V) characteristics. The MIS junction exhibited higher rectifying behavior than the MS junction. The higher barrier height (BH) of the MIS junction compared with the MS junction indicates effective modification by the OG layer. Also, the BH, ideality factor, shunt resistance, and series resistance were extracted based on the I–V characteristic, Cheung’s and Norde’s methods, and the ΨS–V plot. The BH evaluated by Cheung’s and Norde’s methods and the ΨS–V plot was shown to be similar, confirming the reliability and validity of the methods applied. The extracted interface state density (NSS) of the MIS junction was less than for the MS junction, revealing that the OG organic layer reduced the NSS value. Analysis demonstrated that, in the lower bias region, the reverse current conduction mechanism was dominated by Poole–Frenkel emission for both the MS and MIS junction. Meanwhile, in the higher bias region, Schottky emission governed the reverse current conduction mechanism. The results suggest that such OG layers have potential for use in high-quality electronic devices.