ORGANIC HETEROMULTILAYERS - ELECTRONIC-STRUCTURE OF SEXITHIENYL C-60 THIN-FILMS GROWN IN ULTRA-HIGH-VACUUM/

Conjugated polymers have among the largest optical nonlinearities and interesting charge generation and transport properties. The combinatio n of both these characteristics is appealing for optoelectronics. We r eport here on the spectroscopic characterization of alternated multila yers of T-6 and C-60 with the aim of understanding the electronic stru cture of a prototype donor-acceptor multilayer. We demonstrate the abs ence of a stable charge-transfer state at the interface. The strong ph otoluminescence reduction and a much faster radiative lifetime are ind irect evidence of the formation of a metastable charge transfer. Delib erate doping of the fullerene layer with C-70 causes strong photolumin escence trapping into C-(70)-induced traps.