Development of Field-Effect Transistor-Type Photorewritable Memory Using Photochromic Interface Layer

Abstract
We developed a novel field-effect transistor (FET) type photorewritable memory using a photochromic interface layer between the active layer and the gate insulator layer. A diarylethene (DAE) derivative was employed as a photochromic material and pentacene was employed as an active layer. DAE has two types of photoisomer, i.e., the closed- and open-ring isomers. In this study, it was clarified that the highest occupied molecular orbital (HOMO) level of the closed-ring DAE worked as an interfacial deep trap level, and that the generation of the interfacial deep trap level by photoisomerization induced the photoswitching and photomemory behaviors of transistor properties.