| 摘要 |
<p>PURPOSE: To obtain a phase-shifting mask for X-ray lithography by providing a characteristic section with at least one clearly defined sidewall, which is substantially perpendicular to the surface of a carrier and forming the section from a PMMA(polymethyl methacrylate). CONSTITUTION: A phase-shifting characteristic section 24 has a substantially upright sidewall 31, which is substantially parallel to the propagation direction of a substantially collimated incident light 20 and is perpendicular to a surface 28 and a rear face 29 of a carrier 23. The carrier 23 is formed from a thin and fine silicon nitride (Si3 N4 ) film, which is sufficiently so as thin not to absorb a large amount of X-ray flux entering the carrier 23. The material of the phase- shifting characteristic section 24 is PMMA(polymethyl methacrylate), which shifts a phase of the X-ray molecules of an appropriate band by a desired half-wave length, when it is formed in the shape of a film of 2.5 to 3μm thickness. An appropriate target resist layer 33 has a relative clear threshold level 39 and is also constituted of a PMMA layer of 10μm or less in thickness.</p> |
