Sensitivity enhancement of biosensor (SPR) with PtSe₂ using Au–Si–Au thin films

In this study, we presented a novel structure for a highly sensitive surface plasmon resonance (SPR) sensor, we propose a structure which contains six layers: BK7 prism glass, Gold thin film, Silicon sheets, Gold thin film, using transition figure of merit (FOM) 16.43 RUI⁻¹metal dichalcogenides 2D PtSe₂ layer and sample medium. We have been optimizing the thickness of each layer. The highly performance parameters in this biosensor structure are provided in terms of sensitivity(S), detection accuracy (DA), quality factor (QF) and figure of merit (FOM). Here, the addition of the hybrid Silicon—PtSe₂ layer between two gold films increased the sensitivity, but we observed the (DA) and (QF) is decreased. We find the full at half maximum also decreased. We investigated the effect of gold thickness. The maximum sensitivity 200°/RIU and is gained with 35 nm Gold film, 5 nm thickness Silicon and 2 nmPtSe₂ layer, we can be obtained also the configuration with 60 nm Gold thin film and 3 nm thickness Silicon (6 layer) delivers a maximum sensitivity (S) of 206°/RIU with figure of merit (FOM) of 24.03 RUI⁻¹.Our novel structure is optimized for a highly sensitive surface plasmon resonance (SPR) sensor.