Patent ID: 7718006

Claim:
A mask holding structure comprising: a bed plate having a bottom surface on which a substrate is disposed; magnets arranged at positions on the bed plate, end surfaces of the magnets being one of substantially flush with or inside the bottom surface of the bed plate; plugs respectively attracted to the magnets, end surfaces of the plugs being respectively adjacent to the end surfaces of the magnets; and a mask including a base plate and a silicon chip, the base plate having an opening and being made of glass, the silicon chip having an aperture pattern positioned at the opening of the base plate and being bonded onto the base plate by an adhesive agent; each of the plugs having a base part and a protrusion part, each base part having a contacting surface which makes contact with the base plate of the mask, each protrusion part projecting from the contacting surface and being inserted into one of a plurality of holes formed in the base plate, and magnetic attraction forces between the magnets and the plugs acting on the base plate via the contacting surfaces of the base parts of the plugs so that the mask in which the silicon chip has a top position is held by being pressed upward toward the bottom surface of the bed plate with the substrate therebetween.