Effect of humidity and temperature on organic semiconductor CuPc films deposited at different gravity conditions

In this paper effects of humidity and temperature on the electrical properties of thin films of organic semiconductor CuPc deposited from four different solutions (acetone, benzene, methanol and toluene) at different gravity conditions (1g and 70g) by centrifugation are reported. Surface-type samples were fabricated using copper thin films as electrodes deposited on glass substrates. Impedance and capacitance variations at room temperature were measured as a response of relative humidity ranging from 32%~98% at 1 kHz frequency. Similar parameters were measured at 1 kHz and fixed humidity for variable temperatures of 25~70°C. In addition, depending on the solution used during the deposition process, decrease in impedance and increase in capacitance with an increase in either humidity or temperature is also observed. Change in the properties of the CuPc films, deposited at different gravity conditions from different solutions, can be considered due to the changes in the structure and composition of the films. The results of the investigations potentially can be used for the fabrication of organic electronic devices that can be used in instrumentation and optoelectronics.