Laser direct write of silver nanoparticles from solution onto glass substrates for surface-enhanced Raman spectroscopy

A solution based laser direct write technique for patterning of glass substrates with silver nanoparticles is presented. Photoreduction of an AgNO3 solution, by nanosecond UV laser pulses, produces a source solution of silver particles. A glass substrate is then inserted into this solution and the laser is scanned over its surface. Laser-induced fragmentation of the silver particles in the solution, assisted by the melting of the glass surface, produces coatings of silver nanoparticles in the laser-irradiated regions. Strong enhancement of the Raman signal from a dilute Rhodamine 6G analyte confirmed that these substrates are suitable for surface-enhanced Raman measurements.