The invention provides a pixel structure of a dual-layer visible /
infrared hybrid imaging
detector and a fabrication method of the pixel structure. The pixel structure comprises a substrate, a visible sensing region, a
metal interconnector and an
infrared sensing region, wherein the visible sensing region is arranged on the lower surface of the substrate, the
infrared sensing region is arranged on the upper surface of the substrate and comprises a first infrared sensing structure, a second infrared sensing structure, a contact groove structure, a support part and a
dielectric layer, the first infrared sensing structure is arranged on the
dielectric layer, the first infrared sensing structure and the second infrared sensing structure both are connected with the contact groove structure, the contact groove structure is connected with the
metal interconnector, an
electric signal formed by the first infrared sensing structure and the second sensing structure is transmitted to the
metal interconnector through the contact groove structure, a first cavity is arranged in the substrate below the first infrared sensing structure, a second cavity is arranged between the second infrared sensing structure and the first infrared sensing structure, a third cavity is arranged between the support part and the second infrared sensing structure, and a fourth cavity is arranged in the substrate below the
dielectric layer provided with a fourth releasing hole.