Bulk photoconductive gain in pentacene thin films

Bulk photoconductive gain greater than 16 is observed in pentacene thin films deposited onto coplanar interdigitated-electrode photodetector structures. The gain is highest at low light intensity but decreases at higher light intensity due to trap filling effects. The internal photogeneration quantum efficiency is found to be independent of wavelength below the absorption edge with the onset of photocurrent yield occurring at the absorption edge of the film.