Fabrication of periodic microscale stripes of silver by laser interference induced forward transfer and their SERS properties

The micro-stripe structure was prepared by laser interference induced forward transfer technique, composed of Ag nano-particles (NPs). The effects of the film thickness with the carbon nano-particles mixed polyimide (CNPs@PI), Ag film thickness, and laser fluence were studied on the transferred micro-stripe structure. The periodic Ag micro-stripe with good resolution was obtained in a wide range of CNPs@PI film thickness from ∼0.5 to ∼1.0μm for the Ag thin film ∼20 nm. The distribution of the Ag NPs composing the micro-stripe was compact. Nevertheless, the average size of the transferred Ag NPs was increased from ∼41 to ∼197 nm with the change of the Ag donor film from ∼10 to ∼40 nm. With the increase of the laser fluence from 102 to 306 mJ·cm-2per-beam, the transferred Ag NPs became aggregative, improving the resolution of the corresponding micro-stripe. Finally, the transferred Ag micro-stripe exhibited the significant surface enhanced Raman scattering (SERS) property for rhodamine B (RhB). While the concentration of the RhB reached 10-10mol·L-1, the Raman characteristic peaks of the RhB were still observed clearly at 622, 1359 and 1649 cm-1. These results indicate that the transferred Ag micro-stripe has potential application as a SERS chip in drug and food detection.