Local plasma resonance refraction index sensor and manufacturing method thereof

The invention discloses a local plasma resonance refraction index sensor and a manufacturing method thereof. The local plasma resonance refraction index sensor comprises upper metal caps, medium columns and a lower metal aperture array, wherein the medium columns can be low-refractive-index dielectric media such as photoresist, and is positioned between the upper metal caps and the lower metal aperture array. According to the invention, through regulating an incidence angle, metal particles, the length of a period and particle lifting height, a figure of merit can reach 100; the local plasma resonance refraction index sensor can be widely applied to actual biochemistry sensing; and the preparation technique provided by the invention is simple, is low in cost, and is suitable for volume production.