Low-noise integrated biological photoelectrode microprobe and preparation method thereof

The invention discloses a low-noise integrated biological photoelectrode microprobe and a preparation method thereof. The microprobe comprises a light emitting diode, a plurality of microelectrode pairs with a differential function, a noise isolation groove and an external circuit, the light-emitting diode structure sequentially comprises a substrate material, an n-type gallium nitride, an active layer, a p-type gallium nitride, a transparent conductive layer, an insulating passivation layer, a light-emitting diode anode and a light-emitting diode cathode structure, and is used for emitting light and activating biological nerve cells. Each microelectrode pair comprises a first microelectrode used for detecting a biological signal and a second microelectrode used for collecting noise so as to perform differential processing on the biological signal and improve the signal-to-noise ratio, and the microelectrode pairs are symmetrically arranged on the insulating passivation layer in the longitudinal axis directio