Photoluminescence Study of C 70 Film Manufactured by Physical Jet Deposition

We have fabricated C70 film by physical jet deposition (PJD) technique and measured the absorption and photoluminescence (PL) spectra of this kind C70 film. In comparison with the deposited C70 film in high vacuum, the absorption and integrated PL spectra are similar, but there is a big difference in the time-resolved PL. The C70 film made by PJD shows a very fast PL decay of less than 20 ps which should result from the fast relaxation process of C70 molecule in the excited state S1 of this new kind film.