Method for manufacturing a cantilever with sharpened metal needle

Claim 1

A method of manufacturing a cantilever using a silicon process, comprising the steps of: forming an electrode layer on a silicon substrate to form an electric circuit during electrolytic polishing; forming on the electrode layer a thin-film layer having an electric insulation capability; forming in the thin-film layer a cantilever spring element, a contact hole through which to connect the electrode layer and an external lead wire, and a fine hole at an arbitrary position in the spring element to make an electrical connection with the electrode layer; forming an erect metal structure, which can be electrolytically polished, at a position of the fine hole of the thin-film layer; electrolytically polishing the erect metal structure in an electrolytic polishing liquid to form the erect metal structure into a sharpened metal needle; and after the electrolytic polishing process, removing an excess of the silicon substrate and forming the remaining silicon substrate into a mount for the spring element.

Claim 2

A method of manufacturing a cantilever using a silicon process, comprising the steps of: forming an electrode layer on a silicon substrate to form an electric circuit during electrolytic polishing; forming on the electrode layer a thin-film layer having an electric insulation capability; forming in the thin-film layer a cantilever spring element, a contact hole through which to connect the electrode layer and an external lead wire, and a fine hole at an arbitrary position in the spring element to make an electrical connection with the electrode layer; forming an erect metal structure, which can be electrolytically polished, at a position of the fine hole of the thin-film layer; electrolytically polishing the erect metal structure in an electrolytic polishing liquid to form the erect metal structure into a sharpened metal needle; and after the electrolytic polishing process, removing an excess of the silicon substrate and forming the remaining silicon substrate into a mount for the spring element.

Claim 5

A method of manufacturing a cantilever using a silicon process, comprising the steps of: forming a metal needle forming hole in a silicon substrate; forming a thin-film layer having an electric insulation capability on the silicon substrate; forming in the thin-film layer a cantilever spring element and a hole smaller than and at the same position as the metal needle forming hole; forming in the metal needle forming hole an erect metal structure made of an electrolytically polishable material; forming an electrode layer electrically connected to the erect metal structure to form an electric circuit during electrolytic polishing; forming on the electrode layer an electric insulation film to protect the electrode layer from corrosion; forming in the electric insulation film a contact hole through which to connect the electrode layer with a lead wire; etching the silicon substrate to expose the erect metal structure from under the silicon substrate; electrolytically polishing the erect metal structure in an electrolytic polishing liquid to form it into a sharpened metal needle; removing excess portions of the electric insulation layer and the electrode layer after the electrolytic polishing process; joining a mount for holding the spring element onto the thin-film layer; and removing all the remaining silicon substrate.

Claim 6

A method of manufacturing a cantilever using a silicon process, comprising the steps of: forming a metal needle forming hole in a silicon substrate; forming a thin-film layer having an electric insulation capability on the silicon substrate; forming in the thin-film layer a cantilever spring element and a hole smaller than and at the same position as the metal needle forming hole; forming in the metal needle forming hole an erect metal structure made of an electrolytically polishable material; forming an electrode layer electrically connected to the erect metal structure to form an electric circuit during electrolytic polishing; forming on the electrode layer an electric insulation film to protect the electrode layer from corrosion; forming in the electric insulation film a contact hole through which to connect the electrode layer with a lead wire; etching the silicon substrate to expose the erect metal structure from under the silicon substrate; electrolytically polishing the erect metal structure in an electrolytic polishing liquid to form it into a sharpened metal needle; removing excess portions of the electric insulation layer and the electrode layer after the electrolytic polishing process; joining a mount for holding the spring element onto the thin-film layer; and removing all the remaining silicon substrate.

Claim 9

A method of manufacturing a cantilever, comprising the steps of: providing a silicon substrate; forming an electrode layer on the silicon substrate; forming a thin-film layer on the electrode layer; forming in the thin-film layer a spring element and a through-hole, the through-hole being formed at a position adjacent to the spring element; forming an erect metal structure at the position of the through-hole and in electrical contact with the electrode layer; electrolytically polishing the erect metal structure to form a sharpened needle; and removing excess silicon substrate under the spring element to form a cantilevered spring element having the sharpened needle formed integrally therewith.

Claim 10

A method of manufacturing a cantilever, comprising the steps of: providing a silicon substrate; forming an electrode layer on the silicon substrate; forming a thin-film layer on the electrode layer; forming in the thin-film layer a spring element and a through-hole, the through-hole being formed at a position adjacent to the spring element; forming an erect metal structure at the position of the through-hole and in electrical contact with the electrode layer; electrolytically polishing the erect metal structure to form a sharpened needle; and removing excess silicon substrate under the spring element to form a cantilevered spring element having the sharpened needle formed integrally therewith.

Claim 17

A method of manufacturing a cantilever, comprising the steps of: providing a silicon substrate; forming a needle forming hole in the silicon substrate; forming a thin-film layer on the silicon substrate over the needle forming hole; forming in the thin-film layer a spring element and a through-hole, the through-hole being formed at a position adjacent to the spring element and over the needle forming hole; forming an erect metal structure through the through-hole and in the needle forming hole; forming an electrode layer over the thin-film layer and in electrical contact with the erect metal structure; etching the silicon substrate to expose the erect metal substrate; electrolytically polishing the erect metal structure to form a sharpened needle; and removing excess silicon substrate under the spring element to form a cantilevered spring element having the sharpened needle formed integrally therewith.

Claim 18

A method of manufacturing a cantilever, comprising the steps of: providing a silicon substrate; forming a needle forming hole in the silicon substrate; forming a thin-film layer on the silicon substrate over the needle forming hole; forming in the thin-film layer a spring element and a through-hole, the through-hole being formed at a position adjacent to the spring element and over the needle forming hole; forming an erect metal structure through the through-hole and in the needle forming hole; forming an electrode layer over the thin-film layer and in electrical contact with the erect metal structure; etching the silicon substrate to expose the erect metal substrate; electrolytically polishing the erect metal structure to form a sharpened needle; and removing excess silicon substrate under the spring element to form a cantilevered spring element having the sharpened needle formed integrally therewith.