Influence of metal roughness on SPR sensor performance

Roughness of the nano-layer greatly affects the sensor performance. This study is done to quantify the effect of roughness on the sensor performance experimentally. It is seen that the increased thickness of the top metal layer degrades the sensor performance i.e. sensitivity and detection accuracy. The roughness effect on the surface is seen by varying the thickness of intermediate and top metal layers separately. It is seen that 2-5 nm thick intermediate layer and 50 nm thick top layer provides better performance of sensor. Also, mathematical equations are included for the sake of theoretical analysis which indicates the effect of surface roughness on the sensor performance.