| 摘要 |
<p>A method for etching a multi-stage photomask by chlorine for controlling uniformity is provided to easily fabricate a phase shift photomask suitable for patterning a feature with a critical dimension not more than 5 mum by improving uniformity and a phase angle range. A film stack having a partially exposed quartz layer through a pattern layer is supplied to the surface of a substrate support table disposed in a process chamber(202). The quartz layer is etched by using first process gas including at least one of fluorocarbon process gas and chlorine-containing process gas(206). The quartz layer is etched by using second process gas including at least one fluorocarbon process gas(208). The fluorocarbon process gas can include at least one of CF4, CHF3, C2F, C4F4 and C4F8, and the chlorine-containing process gas can include at least one of Cl2 and HCl.</p> |
