Abstract: The present invention discloses a method of increasing the contrast of an EUV mask at inspection by forming a multilayer mirror over a substrate; forming an absorber layer over the multilayer mirror; forming a top layer over the absorber layer; patterning the mask into a first region and a second region; and removing the top layer and the absorber layer in the first region.

Abstract: The present invention discloses an EUV mask having an improved absorber layer with a certain thickness that is formed from a metal and a nonmetal in which the ratio of the metal to the nonmetal changes through the thickness of the improved absorber layer and a method of forming such an EUV mask.

Abstract: A silicon-substrate based reflective photolithographic mask fabrication technique is described. The process begins with a multilayer, resonant reflecting substrate. A thin layer of silicon dioxide or other material capable of acting as an etch stop layer is deposited thereon. Then, a transmissive layer is deposited on the thin layer of etch stop layer. The transmissive layer is substantially transmissive to the wavelength of light used in the photolithography as well as capable of being selectively etched relative to the underlying etch stop layer. Then, the transmissive layer is etched to open preselected, absorptive areas. An absorptive layer is then deposited thereon. The absorptive layer is substantially absorptive to the wavelength of light used as well as capable of completely filling the opened areas of the transmissive layer. The absorptive layer is then planarized, and a thin protective cap is deposited thereon.

Abstract: A novel mask for photolithography in semiconductor processing and the mask fabrication method is disclosed. The mask includes a substrate, a patterned buffer layer, a patterned absorber layer above the patterned buffer layer, and a protective cap. The substrate preferably contains a multilayer resonant reflective surface. The buffer layer and protective cap are transmissive to the wavelength of light used in the photolithography. The absorber layer is absorptive to the wavelength of light used in the photolithography. The mask is fabricated by first depositing the buffer layer. The absorber layer is formed on the buffer layer. Both absorber layer and buffer layer are etched to create a pattern. A protective cap layer is then deposited on the patterned absorber layer and buffer layer, and the protective cap is planarized as needed to create a substantially smooth mask surface.