The analysis of the currentevoltage characteristics of the high barrier Au/Anthracene/n-Si MIS devices at low temperatures H. Kaçus ¸ a , A.R. Deniz a , Z. Çaldıran a ,S ¸ . Aydo  gan a, * , A. Yesildag b , D. Ekinci b a Department of Physics, Faculty of Sciences, University of Atatürk, 25240 Erzurum, Turkey b Department of Chemistry, Faculty of Sciences, University of Atatürk, 25240 Erzurum, Turkey highlights  A new Au/Anthracene/n-Si MIS device was fabricated by using electrochemical polymerization method.  It was seen that the organic layer increased the barrier height of the diode.  The ln IeV characteristics indicates TE conduction dominates the current transport.  The voltage and temperature dependence of R s has been attributed to the density of interface states. article info Article history: Received 7 November 2012 Received in revised form 8 May 2013 Accepted 29 September 2013 Keywords: Electronic materials Interfaces Organic compounds Heterostructures abstract The Au/Anthracene/n-Si/Al MIS device was fabricated on the basis of anthracene film covalently bonded to a Si substrate. The MIS device showed Schottky behavior with barrier heights of 0.85 eV and ideality factors of 1.88 at 300 K. The barrier height of the Au/n-Si has increased after deposition of the anthracene layer onto Si. Temperature dependent currentevoltage (IeV) measurements were per- formed on the Au/Anthracene/n-Si/Al MIS diodes in the range 140e300 K. From the temperature dependence of forward bias IeV, the barrier height was observed to increase with temperature. However, the ideality factor decreased with increasing temperature. The values of activation energy (E a ) and Richardson constant (A*) were determined as 0.24 eV and 7.57  10 6 A cm 2 K 2 from the slope and the intercept at ordinate of the linear region of Richardson plot, respectively. The increase of the series resistance R s with the fall of temperature was attributed to lack of free carrier concentration at low temperatures. Ó 2013 Elsevier B.V. All rights reserved. 1. Introduction In the last three decades, organic semiconductor-based devices have received increased attention in the field of electronic and optoelectronic engineering. Compared to conventional silicon semiconductors, organic materials offer many advantages such as solution processibility, low cost manufacturing, light weight, wide area applications together with fabrication flexibility [1e3] and good mechanical and thermal properties. They have also been increasingly used as active elements in the fabrication of semi- conductor electronic devices like organic photovoltaic devices, organic field-effect transistors, organic light-emitting diodes (OLEDs) and Schottky barrier diodes, rechargeable batteries, nonlinear optical devices and so forth [4e8]. In contrary to the conventional semiconductors, organic mate- rials, in particular, small molecule organic materials are bonded together by comparatively weak van der Waals forces and the charge carriers are highly localized to individual molecular sites. As a result of the weak van der Waals interaction between molecules, the carrier mobility is very low compared to inorganic semi- conductor materials. Well known organic semiconductors can be broadly classified into two main groups on the basis their molecular weight. These are polymers and small molecules. Conjugated polymers with relatively high molecular weight are long molecules. They are often deposited either by spin coating or printing tech- niques [9]. Moreover, they can be formed on large area substrates as thin films since they can form ordered crystalline structures on substrates. Thus, they are very useful for semiconductor technolo- gies. Furthermore, small molecule organic semiconductors with molecular weight less than polymers show very interesting * Corresponding author. Tel.: þ90 0442 231 4073; fax: þ90 442 2360948. E-mail addresses: saydogan@atauni.edu.tr, saydogan43@yahoo.com (S ¸ . Aydo gan). Contents lists available at ScienceDirect Materials Chemistry and Physics journal homepage: www.elsevier.com/locate/matchemphys 0254-0584/$ e see front matter Ó 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.matchemphys.2013.09.030 Materials Chemistry and Physics 143 (2014) 545e551