Maskless patterning characteristics of vanadium pentoxide amorphous films by frequency doubled Q-switched Nd: YAG laser irradiation

摘要

Patterning of vanadium pentoxide (V_2O_5) visible light absorbing amorphous films was attempted using a SHG beam (λ =532nm) of Q-switched Nd:YAG laser. Amorphous V_2O_5 films (350nm thick) were deposited on an optical glass slide substrate 1.4mm thick by normal resistance-heating vacuum evaporation. A sheet beam of the pulse laser with an output power of 1.4J/pulse was used, having a pulse width of 10ns, and a calculated laser fluence of 46.1J/cm~2. The beam with pulse repetition of l0Hz was irradiated in air at room-temperature on the film sample that moved to the direction normal to that of the sheet beam with a speed of 5mm/s. Both direct and indirect beam irradiation through the glass substrate produced a regular stripe pattern due to film removal. Characterization of removed and non-removed film portions in a laser track reveals a molecular and/or nanoclustcr sublimation of amorphous V_2O_5 caused by laser irradiation. This patterning has an advantage of short-time film processing.