Preparation method for surface-enhanced Raman substrate and surface-enhanced Raman substrate structure

The invention provides a preparation method for a surface-enhanced Raman substrate and a surface-enhanced Raman substrate structure, belonging to the field of preparation of micro-nano structures. The preparation method comprises the following steps: selecting a silicon substrate and etching the silicon substrate to produce a silicon pyramid array; putting the silicon pyramid array into a microwave plasma chemical vapor deposition system for growth of a graphene nanoflake; and coating the surface of the graphene nanoflake with a layer of metal particles so as to obtain the surface-enhanced Raman substrate. The surface-enhanced Raman substrate structure is prepared by using the preparation method. The preparation method in the invention can prepare the uniform surface-enhanced Raman substrate with a large area and ensure the metal particles to be pure and free of contaminations. Meanwhile, the preparation method is simple and convenient, and is low in cost. The surface-enhanced Raman substrate prepared in the invention has strong Raman enhancement characteristics and high sensitivity.