Evaluation Of Conduction Mechanism And Electronic Parameters For Au/organic-inorganic Cucl Hybrid Film/ito Structures

摘要

Hybrid materials are capable of combing organic and inorganic compounds into a nano-composite with unique characteristics. An example of such organic-inorganic CuCl hybrid films is studied here using a combination of organic polysilsesquioxane and inorganic CuCl; y-CuCl is an ionic I-VII compound semiconductor material with the zincblende structure at room temperature. It has excellent ultraviolet (UV) emission properties at room temperature and is a promising candidate material for optoelectronic applications. The CuCl hybrid films were deposited on indium tin oxide (ITO)-coated glass by simple spin-coating techniques. Au/CuCl hybrid film/ITO structures were fabricated, and field-dependent electrical studies were carried out at room temperature in the range 2.5 x 105-3.5 x 106 V m"1. We confirm that the organic-inorganic CuCl film structure behaves as an effective single semiconducting medium, possessing bandstructure and other related properties. For electric field magnitudes up to 1.25 x 106 V m"1, an ohmic conduction mechanism was observed, and for field magnitudes > 1.5 x 106 V m"1, Schottky emission conduction prevails in these structures. The electronic parameters were evaluated and an effective barrier height, ideality factor and series resistance were found to be 0.84 ± 0.05 eV, 1.12 ± 0.08 and 50 ± 2 MQ, respectively, whereas the effective barrier height obtained from the C-V measurement was 1.05 ± 0.05 eV. This value is somewhat higher than the value obtained from the I-V measurement. This difference is likely caused by the presence of a thin intervening insulating layer between the hybrid film surface and the Schottky metal. The density distribution of the interface states decreases with an increase of the energy of the interface states. This organic-inorganic CuCl hybrid film behaves as an effective single semiconductor material structure, and a schematic energy-level diagram for the device is proposed.