Film forming apparatus for forming metal film

Abstract

The film forming apparatus includes a pressing mechanism that presses the mask structure by the electrolyte membrane with a fluid pressure of a plating solution. The mask structure includes a screen mask in which a penetrating portion corresponding to a predetermined pattern is formed, and a frame that supports a peripheral edge of the screen mask on a side adjacent to the substrate. In the frame, an inner covering portion made of an elastic material softer than a material of the frame is formed along an opening edge contacting the electrolyte membrane.

What is claimed is: 
     
         1 . A film forming apparatus for forming a metal film having a predetermined pattern on a substrate by electroplating, with a mask structure sandwiched between an electrolyte membrane and a substrate,
 wherein:   the film forming apparatus includes a pressing mechanism that presses the mask structure by the electrolyte membrane with a fluid pressure of a plating solution,   the mask structure includes a screen mask in which a penetrating portion corresponding to the predetermined pattern is formed, and a frame that supports a peripheral edge of the screen mask on a side adjacent to the substrate, and   in the frame, an inner covering portion made of an elastic material softer than a material of the frame is formed along an opening edge contacting the electrolyte membrane.   
     
     
         2 . The film forming apparatus for forming a metal film according to  claim 1 , further comprising an outer covering portion made of the soft elastic material along an outer peripheral edge of the frame facing the electrolyte membrane. 
     
     
         3 . The film forming apparatus for forming a metal film according to  claim 2 , wherein an opposing surface formed between the opening edge and the outer peripheral edge and facing the electrolyte membrane is covered with the soft elastic material such that the inner covering portion and the outer covering portion are continuous. 
     
     
         4 . The film forming apparatus for forming a metal film according to  claim 1 , further comprising a mount base on which the substrate is placed,
 wherein:   the mount base includes a first recess for housing the substrate and a second recess for housing the mask structure while the substrate is housed in the first recess, and   the mount base includes an edge covering portion made of the soft elastic material along an opening edge of the second recess.   
     
     
         5 . The film forming apparatus for forming a metal film according to  claim 1 ,
 wherein:   the screen mask includes a mesh portion in which an opening is formed in a grid pattern, and a mask portion including the penetrating portion, the mask portion being fixed to the mesh portion so as to face the substrate, and   the mask portion elastically deforms by pressing of the electrolyte membrane.