Low-cost SERS substrates composed of hybrid nanoskittles for a highly sensitive sensing of chemical molecules

In this paper, we report on the low-cost and quick fabrication at the 4-in. wafer-scale of hybrid nanoskittles for a highly sensitive detection of chemical molecules. This quick and low-cost fabrication is achieved by using the native oxide layer as a physical etch mask coupled to an evaporation of a gold layer. The hybrid nanoskittles obtained with this technique are disordered on the 4-in. wafer of Si, and a good definition of nanoskittles and a good reproducibility of SERS signal are obtained on the whole wafer. Moreover, we studied experimentally the sensitivity of these Au/Si nanoskittles for SERS sensing. Finally, enhancement factors in the range of 107 − 1.1 × 108 were found for the detection of thiophenol molecules with hybrid nanoskittles.