In a first aspect, a method of fabricating an EUV light source mirror is disclosed which may comprise the acts/steps of providing a plurality of discrete substrates; coating each substrate with a respective multilayer coating; securing the coated substrates in an arrangement wherein each coated substrate is oriented to a common focal point; and thereafter polishing at least one of the multilayer coatings. In another aspect, an optic for use with EUV light is disclosed which may comprise a substrate; a smoothing layer selected from the group of materials consisting of Si, C, Si 3 N 4 , B 4 C, SiC and Cr, the smoothing layer material being deposited using highly energetic deposition conditions and a multilayer dielectric coating. In another aspect, a corrosion resistant, multilayer coating for an EUV mirror may comprise alternating layers of Si and a compound material having nitrogen and a 5 th period transition metal.
1. A method of fabricating an EUV light source mirror, said method comprising the acts of:
providing a plurality of discrete substrates;
securing said substrates in an arrangement wherein each substrate is oriented to a common focal point; and thereafter
polishing at least one of said substrates;
coating each said substrate with a respective EUV reflective multilayer coating.
2. A method as recited in claim 1 wherein said mirror is a normal incidence mirror.
3. A method as recited in claim 1 wherein said arrangement establishes an ellipsoidal mirror.
4. A method as recited in claim 3 wherein said ellipsoidal mirror has a diameter greater than 500 mm.
5. A corrosion resistant, multilayer coating for an EUV mirror, the coating comprises a plurality of bi-layers, each bi-layer comprising:
a layer comprising Si; and
a layer comprising a compound material having nitrogen and a 5 th period transition metal.
6. A coating as recited in claim 5 wherein the 5 th period transition metal is selected from the group of metals consisting of Y, Zr, Nb, Mo, Ru, Rh and Pd.
7. A coating as recited in claim 5 wherein the 5 th period transition metal is selected from the group of metals consisting of Nb, Mo and Ru.
8. A coating as recited in claim 5 wherein the compound material is a nitride.
9. A coating as recited in claim 5 wherein the compound material is a MoN.
10. A coating as recited in claim 5 whereIn the compound material is a MoNbN.
11. A coating as recited in claim 5 wherein the compound material is a NbN.