ZnO-Silicon Enhanced Surface Plasmon Resonance Sensor for Chemical Sensing

This paper presents a new approach sensor, and its effectiveness as a chemical sensor using surface plasmon resonance (SPR) is evaluated. The suggested design consists of a ZnO-Silicon (Si) and silver (Ag) layer, above BaF2 prism and a sensing layer that contains analytes on top. Si has a high refractive index (RI), a semiconducting nature, is compatible with microfabrication techniques and biocompatibility, and is suitable for a wide range of biological and chemical sensing applications. The angular interrogation method is used to analyze the Kretschmann configuration. Sellmeier equations are used to calculate reflectivity and other multilayer design parameters. In this sample, the sensitivity for the sensing medium 1.3264 (D2O), 1.35, and 1.36 (Acetone) is obtained to be 201.8 degrees/RIU, 257.85 degrees/RIU and 311 degrees/RIU, respectively. The corresponding evaluated values for the figure of merit (FOM) are 60.54/RIU, 54.66/RIU, and 70.18/RIU, respectively. Moreover, the ZnO layer's effect is utilized to compare the proposed sensor with other prisms like CsF, NFK51A, and BK7. In various applications, the proposed sensor performance is improved for RI of sensing medium detection between 1.3264 and 1.36.