Photoemission and inverse photoemission studies on a thin film of N,N′-dimethylperylene-3,4,9,10-bis(dicar☐imide)

Abstract

Ultraviolet photoemission (PE) and inverse photoemission (IPE) spectra were measured for thin films ofN,N′-dimethylperylene-3,4,9,10-bis(dicar☐imide) (DM-PBDCI) and perylene-3,4,9,10-tetracar☐ylic dianhydrite (PTCDA), the former known as an n-type organic semiconductor and the semiconducting nature of the latter still unidentified. The electronic structure around the energy gap, obtained from the combination of PE and IPE spectra observed, is found to be almost the same for the two compounds, indicating that PTCDA could be assigned as an n-type semiconductor.