Laser-induced periodic surface structure on polyimide doped with lecithin

The doping effect of lecithin molecules on the formation of laser-induced periodic structure (LIPS) was investigated. The lecithin dopant can decrease the threshold energy of LIPS formation on polyimde (PI) surface, but the LIPS becomes inconsistent and a lot of break line appeared along the LIPS structure when the doping level is up to 30%. The lecithin-doped PI film forms regular LIPS easier when it is irradiated at 266-nm laser beam than at 355-nm laser beam. FT-IR and contact angle results show that the lecithin molecules migrate to the film surface after laser irradiation.