SYNTHESIS AND CHARACTERIZATION OF LONG-ALKYL CHAINED CARBAZOLE DERIVATIVES

Abstract

We have synthesized N-alkylated carbazole with a variation of alkyl size such as ethyl, hexyl, dodecyl and octadecyl group and have made thin film by using the spin-coating method. When N -octadecyl carbazole (NOC) film is made on ITO, the surface of the ITO/NOC layer becomes flatter compared to ITO and ITO/other N -alkylated carbazole layer. As the pendent alkyl chain length of carbazole becomes longer, the PL spectrum of the carbazole derivative becomes smooth and the PL maximum value is slightly shifted to long wavelength. ITO/NOC (100 nm)/ LiF (1 nm)/Al (200 nm) device showed typical I-V characteristics and very weak blue EL light.