SERS enhancement of Ag nanoparticle patterns embedded in glass by two-step ion exchange

Silver nanoparticles embedded in glass are prepared by two different two-step ion exchange methods. In both of these methods, silver ions are introduced into glass in the first silver ion exchange step, but silver ions are reduced into metallic silver using two different second process steps: either post-annealing or subsequent potassium ion exchange. The formed particles are characterized by optical absorption measurements, scanning electron microscopy, transmission electron microscopy and atomic force microscopy. Their application in SERS is demonstrated, and the optimal surface features in terms of SERS enhancement are discussed. With post-annealing, high iron content in glass is needed to achieve high concentration of silver metal nanoclusters. Using double ion exchange, with the second step of potassium ion exchange, reduction of silver ions into metal nanoclusters occurs below aluminium mask. Using such mask, fabrication of silver nanoparticle patterns is also demonstrated.