Thin Solid Films, Vol.420-421, 392-397, 2002
Characterization of hot wall epitaxy grown 1-(2-methoxy benzyloxy)-8-hydroxy-9,10-anthraquinone films
Organic compounds derived from 9,10-anthraquinone has attracted a great deal of interest in recent years because of their optical and photosemiconducting properties. In the present paper, 1-(2-methoxy benzyloxy)-8-hydroxy-9,10-anthraquinone compound has been synthesized and films grown by hot wall epitaxy technique onto the glass substrates held at different temperatures in a vacuum of 1.3 X 10(-3) Pa. The experimental conditions are optimized to obtain better crystallinity of the films. These films are characterized by nuclear magnetic resonance (NMR), optical absorption (IR, visible, near-UV), X-ray diffraction and scanning electron microscopy. In addition, the electrical properties of the films are determined in the temperature range 293403 K. The IR and NMR studies identify the formation of 1-(2-methoxy benzyloxy)-8-hydroxy-9,10-anthraquinone deposits on the glass substrates. A platelet type of crystallites as wide as 2.87 mum are observed in the case of films deposited at 348 K. Observations reveal that the current-voltage characteristics of films show ohmic behaviour of conduction within the investigated field and temperature range. The conduction appears to take place by thermally activated hopping mechanism. The electrical conductivity and carrier concentration of the films increases with the increasing temperature. Analysis of optical absorption measurements indicates that the interband transition energies of films lie in the range from 2.1 to 2.63 eV.
Keywords:synthesis;hot wall epitaxy;1-(2-methoxy benzyloxy)-8-hydroxy-9,10-anthraquinone;electrical properties and measurements;optical properties