ISSN 1063-7826, Semiconductors, 2010, Vol. 44, No. 7, pp. 875–878. © Pleiades Publishing, Ltd., 2010. Original Russian Text © Sh.M. Hasannli, N.N. Mursakulov, U.F. Samedova, N.N. Abdulzade, B.A. Mamedov, R.K. Guseynov, 2010, published in Fizika i Tekhnika Poluprovodni- kov, 2010, Vol. 44, No. 7, pp. 905–909. 875 1. INTRODUCTION Recently, scientific interest in the study of thin films based on different polymers has been increasing from year to year. This is because the dielectric-to- (high-conductivity) state transition, which can be ini- tiated by such physical influences as the electric field [1, 2], temperature [3], low uniaxial pressure [2], and others, is observed in some thin polymer films. We note that field-effect transistors [3, 4], light-emitting diodes [5], sensor and electrochemical transducers, polymer batteries, electroluminescent devices, Schot- tky diodes, and organic transistors based on conduct- ing polymers have already been implemented or are at the implementation stage at the present time. Photo- sensitive polymer semiconductors, due to a combina- tion of photoconductive properties with thermal sta- bility and mechanical and other specific properties of polymers, have become irreplaceable in developing flexible photovoltaic elements for solar energy con- verters. Polymer applications are the result of features of the intermolecular interaction and the possibility of forming donor–acceptor charge–transfer complexes in polymers. It is the complexing ability and efficient charge transfer in complex molecules that result in their polarizability upon exposure to light and, hence, medium photopolarization causing photovoltaic and nonlinear-optical properties. It should be emphasized that the vast majority of studies of electrical characteristics of conducting poly- mers have been carried out for polyacetylene [6] and poly(diphenyl phthalide) [1]. At the same time, fabrication of various multilayer film structures based on semiconductor materials and polymers and the study of their properties [2] remain an urgent problem due to relatively low-cost technol- ogies of polymer films. In this case, researchers' atten- tion has been directed not only to the possibility of using an increasing number of various polymer films and improving such parameters as the operating volt- age and the ratio of currents in turn-on and -off states [7], but also to the study of electrical properties of polymers used and charge transport mechanisms in them [8]. In [9–11], we studied the features of the mecha- nism of the charge-carrier photogeneration in a molecular solid. The role of the weak intermolecular interaction causing carrier photogeneration via Cou- lomb-bound pair states was shown. The objective of research is to experimentally study the conduction and carrier transport mechanisms in heterostructures con- sisting of silicon and thin films of wide-gap polymers such as oligo-β-naphthol. 2. EXPERIMENTAL The samples to be studied were Si/oligo-β-naph- thol/metal structures. The sample areas were 12– 200 mm 2 . Films of oligo-β-naphthol 1–10 μm thick were used as a polymer component. The choice of oligo-β-naphthol as an object of study is caused by its good characteristics of filming on both metal and semiconductor substrates. In Si/oligo-β-naphthol/metal structures, both p- and n-Si (100) were used as a substrate (only the data on n-Si are considered in this paper). Reference metal–polymer–metal sandwich structures were also prepared. When fabricating the sandwich structure, a copper plate was used as a bottom electrode onto which a polymer film was deposited; silver paste was used as a top electrode. In Si/oligo-β-naphthol/metal structures, the ohmic contact to polymer was formed SEMICONDUCTOR STRUCTURES, INTERFACES, AND SURFACES Features of Conduction Mechanisms in Si/oligo-β-Naphthol/Metal Heterostructures Sh. M. Hasannli a ^, N. N. Mursakulov a , U. F. Samedova a , N. N. Abdulzade a , B. A. Mamedov a , and R. K. Guseynov b a Institute of Physics, National Academy of Sciences of Azerbaijan, pr. H. Javid 33, Baku, Az-1143 Azerbaijan ^e-mail: Hasanli_sh@rambler.ru b Ganja State University, pr. Khatai 187, Ganja, AZ-2000 Azerbaijan Submitted September 15, 2009; accepted for publication December 18, 2009 Abstract—Conduction mechanisms in Si-polymer-metal heterostructures with oligo-β-naphthol as a wide band-gap polymer have been studied. The results obtained are explained within the models of hopping trans- port via trap levels, Schottky emission, and field tunneling emission. Different charge transport mechanisms operate in different temperature ranges and under different electric fields. DOI: 10.1134/S1063782610070080