MEASURING METHOD OF THE RASIDUAL STRESS OF A METAL SUBSTRARE FOR DEPOSITION MASK AND THE METAL SUBSTRATE HAVING IMPROVED RASIDUAL STRESS

摘要

An embodiment of the present invention relates to a method for measuring a residual stress of a metal plate used in manufacturing a mask for deposition to deposit an OLED pixel, wherein the metal plate has a first direction and a second direction crossing the first direction. The residual stress measuring method comprises the following steps: extracting a sample metal plate from the metal plate; and measuring the residual stress of the sample metal plate, wherein a first residual stress rate and a second residual stress rate of the metal plate are 0.06 or less, the first residual stress rate is less than the second residual stress rate, the first residual stress rate is the residual stress rate of an arbitrary first sample metal plate in the first direction and the second residual stress rate is the residual stress rate of an arbitrary second sample metal plate in the second direction.