Preparation method of micro-nano structure, micro-nano structure and electronic component

The embodiment of the invention provides a preparation method of a micro-nano structure, which comprises the following steps of: providing a silicon substrate, and depositing a first metal layer with a first preset thickness on the surface of the silicon substrate; photoresist is spin-coated on the first metal layer, the photoresist is photoetched to form a pattern, and the first metal layer is exposed; etching the exposed first metal layer to expose the surface of the silicon substrate; etching the exposed surface of the silicon substrate to form a micron structure; depositing a second metal layer with a second preset thickness on the surface of the silicon substrate; removing the photoresist; annealing the whole silicon sheet based on a predetermined temperature to form a nanopore in the second metal layer; providing a first corrosive liquid, and corroding the joint of the silicon substrate and the second metal layer to form a nano structure; and removing the first metal layer and the second metal layer to