| 摘要 |
<p>A method for forming a photomask is provided to remove contaminants from the rear side of the photomask, thereby preventing the deterioration of light transmissivity. A mask pattern(200) is formed on a quartz substrate(100). A rear-side treatment is performed to increase the roughness of the rear side of the quartz substrate. In the rear-side treatment, plasma is supplied to the rear side of the quartz substrate and therefore the roughness is increased. In the rear-side treatment, ultrasonic wave is applied to the rear side of the quartz substrate and therefore the roughness is increased. In the rear-side treatment, UV is applied to the rear side of the quartz substrate and therefore the roughness is increased. The roughness of the rear side of the quartz substrate is increased to 10Å or less.</p> |
