The Study Of High Performance Surface-enhanced Raman Scattering Substrates Developed By Self-assembly

Surface enhanced Raman scattering(SERS) technique is a kind of non-contact test technology which can provide single molecule information, with advantages suc h as super sensitivity, low cost, and real-time detection, it is very important in the field of material testing,optical sensing, and obtained widespread application in a single molecular biological sensing and environmental monitoring. Along with the SERS found in Fleishman M's study at Southampton University in 1977, Raman material detection and mechanism research raised quickly, and thanks to the preparation of SERS substrate, it gradually made some progress in application field of material testing practically.In order to obtain good characteristics SERS substrate, many methods of Micro/Nano machining technology has been applied in SERS research and development. Such as Electrochemical rough methods, chemical synthesis method in early years,and then the self-assembly and NSL technology which could ensure the substrate low-cost and uniformity at the same time. These technologies provide an important role in widely use of SERS, however single structures, the complex of preparation technics and high fabrication cost, become the important limiting factors which effect SERS technology further promotion and application.To avoid and solve these difficulties, we proposed a simple and low cost method based on ?bottom-up? technology in SERS substrate preparation. ?Hot spots? can be controlled through the coating process and the choice of structure unit. This paper also made some researches on its mechanism basing on FIB technique. Preparation of substrate is 3D spheroidal array SERS substrate, which has metal particle and gold film clearance structure on its surface where can provide electromagnetic enhancement. Substrate with 414.2nm PS nanosphere as support layer has 107 Raman enhancements. The result of our substrate is described by Raman spectra.Finally, paper also tried to prepare SERS substrate combined self-assembly with FIB, in order to find a new way to combine the advantages of these two kinds of processing methods.