Patent ID: 9627444
Date: 2017-04-18
CPC Classifications: C23C,C23F,G03F,H01L

Claim:
1. A method of manufacturing a metal mask, the method comprising: forming a first recessed portion in a first surface of a base member, the base member having a second surface that is opposite to the first surface; after the formation of the first recessed portion, forming an edge portion of the first recessed portion, the edge portion being bounded by a third surface of the base member and an interior wall surface, the third surface being parallel to the first surface and being separated from the first surface by a constant depth, the interior wall surface being perpendicular to at least one of the first surface and the second surface of the base member; thereafter, forming a second recessed portion in the second surface of the base member; and communicating the first recessed portion and the second recessed portion of the base member.