We demonstrated enhanced surface plasmon resonance (SPR) detection by incorporating an indium tin oxide (ITO) layer on a thin gold film. Porous ITO layers were fabricated by e-beam evaporation and slanted deposition at room temperature and the ITO structure was optimized in terms of the surface roughness and the SPR curve characteristics. In sensing experiments, the results obtained by ethanol-water mixture test showed that SPR substrates with a porous ITO layer provided a notable sensitivity improvement compared to a conventional bare gold film, which is attributed to the nonlinear dispersion characteristic of surface plasmons. Our approach is intended to show the feasibility and extend the applicability of the porous ITO-mediated SPR biosensor to diverse biomolecular binding events.

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