Extreme ultraviolet mask and method for forming the same
View Patent ↗A photolithography mask includes a substrate, a reflective multilayer structure over the substrate, an adhesion layer over the reflective multilayer structure, a capping layer over the adhesion layer, and a patterned absorber layer over the capping layer. The capping layer includes a non-crystalline conductive material.
1. A photolithography mask, comprising:
a substrate;
a reflective multilayer structure over the substrate;
an adhesion layer in direct contact with a topmost surface of the reflective multilayer structure;
a capping layer over the adhesion layer; and
a patterned absorber layer over the capping layer.
2. The photolithography mask of claim 1 , wherein the adhesion layer comprises a dielectric material.
3. The photolithography mask of claim 2 , wherein the dielectric material comprises silicon dioxide, silicon nitride or silicon oxynitride.
4. The photolithography mask of claim 1 , wherein the capping layer comprises a non-crystalline conductive material.
5. The photolithography mask of claim 4 , wherein the non-crystalline conductive material comprises a transition metal selected from ruthenium, iridium, rhodium, platinum, palladium, osmium, rhenium, vanadium, tantalum, hafnium, tungsten, molybdenum, zirconium, manganese and technetium.
6. A method for forming a photolithography mask, comprising:
forming a reflective multilayer structure over a first side of a substrate;
forming an adhesion layer over the reflective multilayer structure;
depositing a capping layer over the adhesion layer;
depositing an absorber layer over the capping layer; and
etching the absorber layer to form a plurality of openings exposing a surface of the capping layer.
7. The method of claim 6 , wherein the adhesion layer comprises a dielectric material selected from the group consisting of silicon dioxide, silicon nitride and silicon oxynitride.
8. The method of claim 7 , wherein forming the adhesion layer comprises depositing the dielectric material over the reflective multilayer structure.
9. The method of claim 7 , wherein forming the adhesion layer comprises converting a surface portion of a topmost layer in the reflective multilayer structure using oxidation and/or nitridation to form the dielectric material.
10. The method of claim 6 , wherein the capping layer comprises an amorphous conductive material.
11. The method of claim 10 , wherein the capping layer comprises amorphous ruthenium.
12. The method of claim 10 , wherein the capping layer further comprises one or more dopants selected from the group consisting of niobium, titanium, zirconium, yttrium, boron and phosphorus.
13. The method of claim 12 , wherein depositing the capping layer comprising co-depositing the conductive material and the one or more dopants using a deposition process.
14. The method of claim 8 , further comprising depositing a conductive layer on a second side of the substrate opposite the first side.
15. A lithography patterning process comprising transferring a pattern from a photolithography mask to a semiconductor wafer, wherein the photolithography mask comprises:
a substrate;
a reflective multilayer structure over the substrate;
an adhesion layer in direct contact with a topmost surface of the reflective multilayer structure;
a capping layer over the adhesion layer; and
a patterned absorber layer over the capping layer.
16. The lithography patterning process of claim 15 , wherein the adhesion layer comprises a dielectric material, and the capping layer comprises a non-crystalline conductive material.
17. The lithography patterning process of claim 15 , wherein the adhesion layer comprises silicon dioxide, silicon nitride or silicon oxynitride.
18. The lithography patterning process of claim 15 , wherein the capping layer comprises a transition metal selected from ruthenium, iridium, Rhodium, platinum, palladium, osmium, rhenium, vanadium, tantalum, hafnium, tungsten, molybdenum, zirconium, manganese and technetium.
19. The lithography patterning process of claim 15 , wherein the capping layer further comprises one or more dopants selected from the group consisting of niobium, titanium, zirconium, yttrium, boron and phosphorus (P).
20. The lithography patterning process of claim 19 , wherein a concentration of the one or more dopants in the capping layer is less than about 50 atomic percent.