Stability of Diodes with Poly(3-hexylthiophene) and Polyazomethines Thin Organic Layer

Abstract

Herein we report results of studies on stability of diodes based on organic semiconductors such as poly (3-hexylthiophene) (P3HT) and soluble derivative of polyazomethine poly(1,4-(2,5-bisoctyloxy phenylenemethylidynenitrilo)-1,4-phenylenenitrilomethylidyne), (BOO-PPI). Both polymers were deposited on glass/ITO substrate with or without covering with blocking layer: poly(3,4-ethylenedioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) and nished with Al back electrode. Prepared devices were studied by monitoring their electrical conductivity under nitrogen atmosphere and ambient air conditions. Under nitrogen atmosphere a marked in uence of presence of the blocking layer on the diodes electrical conductivity was revealed. The P3HT diodes prepared without PEDOT:PSS thin lm shown quick degradation, whereas presence of these layers stabilizes electrical conductivity in these devices. Inversely, the PPI based diodes without the PEDOT:PSS revealed stable conducting properties, while corresponding diodes with PEDOT:PSS layer showed degradation traces of their conducting properties.