The Polymer Society of Korea

Abstract

Self-assembled monolayers (SAMs) are widely used as underlying layers for organic semiconductors in organic field-effect transistors (OFETs). Although several studies have reported vapor-phase doping using SAM materials, the doping mechanism has not yet been clearly elucidated. In this study, we investigate the doping effects of SAMs on conjugated polymers (CPs) and aim to elucidate the underlying mechanism. Using a vapor-phase doping approach, we confirm that various SAM materials can induce p-type doping in conjugated polymers. The doping efficiency was monitored as a function of time through electrical property measurements, and surface analyses were conducted to observe surface changes during the doping process, thereby confirming the vapor-phase doping behavior. Furthermore, changes in crystallinity after doping and Kelvin probe force microscopy (KPFM) measurements were used to elucidate the influence of vapor-phase doping on conjugated polymers.