Method for manufacturing highly sensitive surface-enhanced Raman scattering porous silicon photonic crystal biosensor

The invention discloses a method for manufacturing a highly sensitive surface-enhanced Raman scattering porous silicon photonic crystal biosensor. The method comprises the steps of S1, based on the electrochemical corrosion method, manufacturing the surface of an N-type monocrystalline silicon into a porous silicon Bragg reflector, wherein macroporous layers and mesoporous layers are alternately stacked up; S2, adopting the porous silicon Bragg reflector as a base material to manufacture silver nano-particles that attached in a pore passage. In this way, the porous silicon photonic crystal biosensor can be obtained. According to the technical scheme of the invention, based on the special photon transmission characteristics of photonic crystals and the optical long-range pool effect, the action length of the light with matters is increased. The detection signal intensity and the sensitivity of the biosensor are effectively improved. The intensity of a Raman signal is approximately 5 times the intensity of a single layer of porous silicon, and the detection limit thereof is improved by two orders of magnitudes compared with that of the single layer of porous silicon.