Film forming apparatus for metal film

Abstract

The film forming apparatus is a device that forms a metal film on the surface of a base material. The film forming apparatus includes a container containing a plating solution, an electrolyte film that covers an opening of the container formed at a position facing the base material, and a positive electrode disposed above the electrolyte film in the container. It includes a power source that applies a voltage between the positive electrode and the base material. On the surface of the positive electrode, a surface facing the electrolyte film has a plurality of curved surfaces arranged in a convex manner toward the electrolyte film. A through hole passing through the positive electrode is formed between the plurality of curved surfaces.

What is claimed is: 
     
         1 . A film forming apparatus that forms a metal film on a surface of a base material, comprising:
 a container that contains a plating solution;   an electrolyte film that covers an opening of the container formed at a position facing the base material;   a positive electrode disposed above the electrolyte film in the container and being insoluble in the plating solution; and   a power source that applies a voltage between the positive electrode and the base material, wherein:   a plurality of curved surfaces convexly curved toward the electrolyte film is arranged on a facing surface that faces the electrolyte film, of a surface of the positive electrode; and   a through hole that penetrates the positive electrode is formed between the curved surfaces.   
     
     
         2 . The film forming apparatus according to  claim 1 , wherein the curved surfaces are each a part of a spherical surface. 
     
     
         3 . The film forming apparatus according to  claim 2 , wherein top regions of the curved surfaces are each a surface that has been subjected to a water-repellent treatment. 
     
     
         4 . The film forming apparatus according to  claim 1 , further comprising a vibration device that vibrates the positive electrode. 
     
     
         5 . The film forming apparatus according to  claim 4 , wherein the vibration device vibrates the positive electrode along a horizontal direction, and vibrates the positive electrode with an amplitude greater than or equal to a hole width of the through hole along the horizontal direction in which the positive electrode is vibrated.