| 摘要 |
PURPOSE:To improve warp of a frame by installing a ring-shaped plate which is formed of a member whose thermal expansion coefficient is larger than that of Si to the rear side of an Si frame at a temperature higher than one used at the time of X-ray exposure. CONSTITUTION:A central section of a film 3 on a lower side is removed by etching to form an X-ray exposure area 4. This is put in a high temperature bath and a ring-shaped plate 7 which is formed by a member such as Ti, Al whose thermal expansion coefficient is larger than that of Si is mounted to an outer side of the remaining film 3 on the lower side. That is, the ring-shaped plate 7 which is formed by a member whose thermal coefficient is larger than that of Si is mounted to a rear side of a frame 5 of Si at a temperature higher than an ordinary temperature; therefore, the plate 7 tends to shrink at an ordinary temperature, thus acting to restore warp of a mask. Warp of a mask can be improved in this way. |
