| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for accurately measure the stresses of a plurality of membranes, in mask blanks having the plurality of membranes. SOLUTION: When a power supply is used for applying a voltage to a blanks- fixing plate 3, static electricity force that is an attraction force acts between the blanks-fixing plate 3 and a post section 10 of the mask blanks 2, and the post section 10 of the mask blanks 2 is fixed to the blank-fixing plate 3. Pressure is applied on a pressurization chamber 1, where the pressurization means for varying pressure is connected, pressure is applied to the membrane 9 via a hole 8 on the blanks-fixing plate 3, and the membrane 9 of the mask blanks 2 is expanded. While pressure in a pressurization chamber 1 is being measured by a pressure gauge, the amount of expansion in one membrane of the mask blanks 2 is measured, by a means for measuring the amount of displacement in the membrane. While the pressure in the press chamber 1 is being changed, the amount of expansion in the membrane is measured for obtaining the stress and the Young's modulus.</p> |
