Blank masks for extreme ultra violet lithography, methods of fabricating the same, and methods of correcting registration errors thereof
View Patent ↗A blank mask includes a substrate having a first surface and a second surface which are opposite to each other. The substrate includes a trench having a predetermined depth from the second surface. A reflection layer is disposed on the first surface of the substrate to reflect extreme ultraviolet (EUV) rays. An absorption layer is disposed on the reflection layer opposite to the substrate to absorb EUV rays. A conductive layer is disposed in the trench to expose portions of the substrate. The conductive layer includes first conductive lines and second conductive lines intersecting the first conductive lines, and the exposed portions of the substrate are two dimensionally arrayed to have island shapes.
1. A blank mask for extreme ultraviolet (EUV) photolithography, the blank mask comprising:
a substrate having a first surface and a second surface which are opposite to each other, the substrate including a trench having a predetermined depth from the second surface;
a reflection layer disposed on the first surface of the substrate to reflect extreme ultraviolet (EUV) rays;
an absorption layer disposed on the reflection layer opposite to the substrate to absorb extreme ultraviolet (EUV) rays; and
a conductive layer disposed in the trench to expose portions of the substrate,
wherein the conductive layer includes first conductive lines and second conductive lines intersecting the first conductive lines, and the exposed portions of the substrate are two dimensionally arrayed to have island shapes.
2. The blank mask of claim 1 , wherein a surface of the conductive layer is coplanar with the second surface of the substrate.
3. The blank mask of claim 1 ,
wherein the first conductive lines are disposed to have stripe shapes extending in a first direction and are arrayed in a second direction intersecting the first direction to be spaced apart from each other; and
wherein the second conductive lines are disposed to have stripe shapes extending in the second direction and are arrayed in the first direction to be spaced apart from each other.
4. The blank mask of claim 1 , wherein a width of each of the first conductive lines is substantially equal to a width of each of the second conductive lines.
5. The blank mask of claim 1 , wherein the exposed portions of the substrate are uniformly distributed at the second surface of the substrate.
6. The blank mask of claim 1 , wherein the blank mask further comprises an insulation layer on the exposed portions of the second surface.
7. The blank mask of claim 6 , wherein the insulation layer includes a material layer that transmits lights or rays.
8. The blank mask of claim 1 , further comprising at least one of a capping layer and a buffer layer between the reflection layer and the absorption layer.