Characterization of the small molecule based organic thin film fabricated by electrospray deposition technique

A novel route for the fabrication of the SM based 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) organic thin film by electrospray deposition (ESD) technique has been presented in this paper. The tailoring of the film thickness was also performed by varying the number of deposition passes at a constant substrate speed. The structural and optical characterizations of the fabricated BCP thin film were thoroughly investigated. The energy gap of the fabricated thin film was measured to be 3.5 eV. Furthermore, the electrical performance of the BCP thin film was verified by performing current-voltage measurement of the prototype organic diode device having fabricated BCP film as a buffer layer. The current density-voltage characteristic curve of the organic device showed non linear diode like behavior, thereby confirming the proper interference established between organic diode adjacent layers. At low voltage, the device showed ohmic conduction, where as the space charged limited current and trap charge limited current mechanism have been found to be dominant in the fabricated organic device at higher voltage. Overall, the results suggest that the ESD approach will be promising for organic semiconductor device fabrication at low cost and with low material loss.