Quantum wire and dot formation by chemical vapor deposition and molecular layer deposition of one-dimensional conjugated polymer

Abstract

Using the reaction between two types of molecules, I [terephthalaldehyde (TPA)] and II [p-phenylenediamine (PPDA), 4,4′-diaminodiphenyl ether (DDE), 4,4′-diaminodiphenyl sulfide (DDS), or 1,4-diaminodiphenylmethane (DDM)], we fabricate quantum wires and quantum dots by chemical vapor deposition. In the TPA/PPDA film, an exciton absorption peak occurs near 500 nm, indicating that long conjugated chains (quantum wire) are formed. In TPA/DDE, TPA/DDS, and TPA/DDM films, which have quantum dots consisting of three benzene rings separated by barriers of -O, -S-, and -CH2- bonds, blue shifts of the absorption band occur due to an electron confinement. We also demonstrate molecular layer deposition of the TPA/PPDA film.