Nonvolatile Organic Field-Effect Transistors Memory Devices Using Supramolecular Block Copolymer/Functional Small Molecule Nanocomposite Electret

Organic field-effect transistors (OFETs) memory devices based on hybrid nanocomposite electret were fabricated by cooperative supramolecular polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) with two different block compositions (asymmetric Li and symmetric L2) that contain hydroxyl-functionalized ferrocene small molecules (FMs). Because of the selective hydrogen interaction between the hydroxyl groups of FM and pyridine groups in P4VP block, the small FMs can preferentially disperse in the P4VP nanodomain, which can be used as nanostructured charge-trapping nanocomposite electret (L1-FMX and L2-FMX) under solvent-annealing process. The charge-storage functionalities can be easily tailored by morphologies of the hybrid nanocomposite thin film and spatial distribution of the FM molecules in which the relative molecular mass of block copolymers and the FM loading ratio can further control both of them. These block copolymer nanocomposite thin film electrets with charge-controlling guest FM for OFETs memory devices exhibit significant features including the ternary bits storage, high-density trapping sites, charge-carrier trapping of both polarities (ambipolar trapping), and solution processing that can make important progress for future advanced storage and memory technology.