Patent ID: 7794545

Claim:
A mask which is used to form on a surface of a substrate a plurality of linear film members disposed parallel to each other by fixing one surface of the mask to the substrate and supplying a film material through the other surface of the mask by the use of a vapor process, the mask comprising: a mask body having a plurality of partition walls in which a plurality of openings are disposed, the plurality of openings corresponding to patterns of the linear film members; and reinforcement ribs which are disposed so as to cross within the partition walls and the openings and which are configured to prevent deformation of the mask body due to the weight thereof, wherein the reinforcement ribs are disposed close to the other surface of the mask in the thickness direction of the openings, and wherein each of the openings has an enlarged width portion in the middle portion in the longitudinal direction, and wherein the reinforcement ribs are disposed in the enlarged width portions.