To accurately manufacture a sphere and a spherical shell part by forming a sacrificial film to cover the sphere, forming a functional film including an electric conductor pattern and an insulator, forming a structural film of the insulator to form etching pores reaching the sacrificial film from the outer surface, and removing the sacrificial film by means of a gas etching agent.

A sphere 10 formed of monocrystal silicon is prepared, and an electric conductor film is formed on the surface. A silicon film 12 is then formed on the surface of the sphere 10, and a metal film 14 is formed to cover the silicon film 12. An electrode pattern 15 is formed on the metal film 14 by etching, and an insulating film 16 is formed. A cable way pattern formed of a conductor film 18 is formed on the silicon dioxide film 16, and resist film 20 is formed. After applying resist, grooves used for bump formation and micro pores used for gas phase etching are formed, and bumps 22 are formed. Finally the sacrificial film 12 is removed to form a clearance 11. The sphere and an electrode can thereby be manufactured at the same time.