A mechanism to which a liquid-repellent structure hard to be exfoliated is applied.The tip of each of microprojections has a generally spherical surface. When a liquid metal (8) comes into contact with such a surface, the liquid metal (8) cannot enter the spaces among microprojections and is supported by the surfaces of the tips only with point contact.Therefore, the liquid metal (8) neither wets the surface of the base material nor spread over the surface.The liquid-repellent surface (11) has a structure such that the liquid metal (8) is supported by point contact of the many microprojections and repelled by the surface (11), and does not wet the surface (11).