Surface Activation of Thin-Film Transparent Electrodes for Application in Organic Optoelectronics

   Aim is to development of a reproducible and mild method for cleaning and activating the surface oftransparent conductive electrodes (ITO, FTO) that enables high surface energy while preserving the substrate’s morphology and electrophysical properties for their subsequent application in organic
optoelectronics.

   Methodology. A new cleaning protocol was developed based on treating surfaces in a boiling ammonia–peroxide solution followed by activation in an ozone chamber. To evaluate the method’s effectiveness, contact angle measurements were performed followed by surface energy calculations, as well as analysis of surface morphology and its electrophysical characteristics.

   Results. It is shown that the developed protocol enables achieving surface energy values of up to ~70 mJ/m², indicating a significant increase in hydrophilicity and a high degree of cleaning. It has been established that the method does not lead to degradation of the conductive layers, preserving their initial morphology and electrical conductivity, unlike traditional acid-based approaches.

   Research implications. The high surface energy achieved through ammonia–peroxide solution treatment combined with ozone activation contributes to improved adhesion and uniformity of organic layer deposition, which is critically important for enhancing the efficiency and stability of
OLEDs, OPVs, and other hybrid devices.

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