Patent ID: 7530462

Claim:
A wafer storage container comprising: an outer peripheral portion located outside an outer peripheral edge of a wafer; and a placing portion which extends from a position lower than an uppermost surface of the outer peripheral portion to the inside of the wafer in the radial direction and on which the wafer is placed at a position lower than the uppermost surface of the outer peripheral portion, wherein the placing portion has a first inclined surface which descends toward the inside of the wafer in the radial direction and can be brought into contact with only the outer peripheral edge of the wafer when the wafer is placed and a second inclined surface which is on a rear side of the first inclined surface and can be brought into contact with only the outer peripheral edge of a second wafer positioned below the second inclined surface when a plurality of wafer storage containers are stacked, wherein the outer peripheral portion has a plurality of projecting portions projecting upward and arranged on an upper surface of the outer peripheral portion at predetermined intervals, and the first inclined surface is connected to the wafer from both the projecting portions and a recessed portion between the projecting portions to make it possible to horizontally hold the wafer at the same level when the wafer is placed.