Characteristics of fullerene-based diode structures on polymer and glass substrates

Chemical structure of the top Al/C60 interface in Al/С$_{60}$/ITO sandwich structures (Al is the thermally deposited top aluminum layer, С$_{60}$ is the thermally deposited fullerene layer, ITO is the double indiumtin oxide, the role of the substrate is played by Lavsan (polyethylene terephthalate), or glass) is studied by time-of-flight secondary mass spectrometry (ToF-SIMS) with depth profiling. The study is stimulated by the recently found specific features of the photovoltaic effect in fullerene-containing sandwich structures on glass or polymer substrates. It is found that the chemical composition of the top Al/С$_{60}$ interface is not the same on different substrates. This leads to differences in the photovoltaic conversion parameters for more complex thin-film structures with a molecular heterojunction.