Abstract: A sensor includes: a substrate, a chip, and a protective layer. The chip is arranged on a surface of the substrate, the protective layer includes a silica gel protective layer, a silica gel active layer, and a strength-increasing protective layer. the silica gel protective layer is coated on the chip and adheres to the substrate; the silica gel active layer is coated on an outer surface of the silica gel protective layer, and adhesion of the silica gel active layer is greater than adhesion of the silica gel protective layer; the strength-increasing protective layer is coated on and adheres to an outer surface of the silica gel active layer, and the strength-increasing protective layer adheres to the substrate; and a strength of the strength-increasing protective layer is greater than a strength of the silica gel protective layer.