Surface enhanced Raman spectroscopic studies of metal nano hole array
|School||University of Electronic Science and Technology|
|Keywords||metallic nanoholes arrays SERS SPR LSPR FDTD|
Because of a set of the advantages of Ranam Spectrum, such as:no touch and no damage the samples; no need to prepare the samples; quick analyses and the defining the characters and structures of different of materials; being suited to the black sample in water; and measuring under the conditions of high t or low temperature, Raman spectrum is widely used to Materials Physics, Biomedicine, and Surface Science, etc. However, the intensity of the spectrum is so weak that the study of the usage is very limited. And then surface enhanced Raman scattering (SERS) was discovered, a way to solve the problem was found accordingly. The SERS substrates, metallic nanoparticle or nanohole arrays, can excite the surface Plasmon resonant by tailoring the size, the shape of the particles or holes, changing the structures of the arrays, to achieve the aim that enhancing the electronic field and SERS.The main work of this paper, is studying how the size of the nanoholes of the array impinge on the enhancement of the electric field firstly; secondly is verifying the enhancement. That can be described as follows:1. Study the distribution of the electric field on the Au film with rhombus hole array, then optimize the size of the array. In this process, we discovered that, Localize Surface Plasmon Resonant (LSPR) is very intensive to the size of the rhombuses (approximately2nanometer). It is too hardly to achieve such a precision according to the present fabrication technology. Thus in the process of optimizing the array, we just took the Surface Plasmon Resonant (SPR)in to account.2. Fabricate the array with the parameters of calculation by means of focus ion beam (FIB) direct milling technique. Then measure the Raman spectrum on the substrate. In comparison to the theoretical calculation, experimental results are in agreement with that of the theory.