Membrane for EUV lithography
Membranes for EUV lithography are disclosed. In one arrangement, a membrane has a stack having layers in the following order: a first capping layer including an oxide of a first metal; a base layer including a compound having a second metal and an additional element selected from the group consisting of Si, B, C and N; and a second capping layer including an oxide of a third metal, wherein the first metal is different from the second metal and the third metal is the same as or different from the first metal.
1 . A membrane at least partly transmissive of EUV radiation for EUV lithography, the membrane comprising:
a solid core layer comprising one or more selected from: YSi 2 , ZrSi 2 , LaSi 2 , NbSi 2 , MoSi 2 , RuSi 2 or any other stable stoichiometry of Mo and Si, of Ru and Si, of Zr and Si, of La and Si, of Y and Si, or of Nb and Si; and
a capping layer providing an outer surface of a first major side and/or second, opposite major side of the membrane, wherein the core layer is thicker than the capping layer.
2 . The membrane according to claim 1 , wherein the core layer comprises one or more selected from RuSi, LaSi, Mo 3 Si, Mo 3 Si 3 , ZrSi, Zr 2 Si, TiSi or Nb 5 Si 3 .
3 . The membrane according to claim 2 , wherein the core layer further comprises one or more selected from: YSi 2 , ZrSi 2 , LaSi 2 , NbSi 2 , MoSi 2 or RuSi 2 .
4 . The membrane according to claim 1 , wherein the core layer comprises a stable stoichiometry of Mo and Si.
5 . The membrane according to claim 2 , wherein the capping layer comprises SiN.
6 . A pellicle assembly comprising:
a frame; and
the membrane of claim 1 .
7 . A patterning device assembly comprising the pellicle assembly of claim 6 and a patterning device.
8 . A dynamic gas lock assembly comprising the membrane of claim 1 .
9 . A membrane at least partly transmissive of EUV radiation for EUV lithography, the membrane comprising:
a solid core layer comprising one or more selected from:
a stable stoichiometry of Y and Si other than YSi 2 ,
a stable stoichiometry of Zr and Si other than ZrSi 2 ,
a stable stoichiometry of La and Si other than LaSi 2 ,
a stable stoichiometry of Nb and Si other than NbSi 2 ,
a stable stoichiometry of Mo and Si other than MoSi 2 , or
a stable stoichiometry of Ru and Si other than RuSi 2 ; and
a capping layer providing an outer surface of a first major side and/or second, opposite major side of the membrane, wherein the core layer is thicker than the capping layer.
10 . The membrane according to claim 9 , wherein the core layer comprises one or more selected from: RuSi, LaSi, Mo 3 Si, Mo 5 Si 3 , ZrSi, Zr 2 Si, TiSi or Nb 5 Si 3 .
11 . The membrane according to claim 9 , wherein the core layer further comprises one or more selected from: YSi 2 , ZrSi 2 , LaSi 2 , NbSi 2 , MoSi 2 , or RuSi 2 .
12 . The membrane according to claim 9 , wherein the core layer comprises a stable stoichiometry of Mo and Si, and wherein the capping layer comprises SiN.
13 . The membrane according to claim 9 , wherein the capping layer comprises carbon having a proportion of sp 3 carbon of at least 20%.
14 . The membrane according to claim 9 , wherein the capping layer comprises a transition metal doped with an alkali metal or an alkaline earth metal.
15 . A pellicle assembly comprising:
the membrane of claim 9 ; and
a frame.
16 . A membrane at least partly transmissive of EUV radiation for EUV lithography, the membrane comprising a solid core layer comprising a compound comprising one or more selected from: a stable stoichiometry of Mo and Si, a stable stoichiometry of Ru and Si, a stable stoichiometry of Zr and Si, a stable stoichiometry of La and Si, a stable stoichiometry of Y and Si, or a stable stoichiometry of Nb and Si.
17 . The membrane according to claim 16 , further comprising a capping layer providing an outer surface of a first major side and/or second, opposite major side of the membrane, wherein the capping layer comprises carbon having a proportion of sp 3 carbon of at least 20%.
18 . The membrane according to claim 16 , further comprising a capping layer providing an outer surface of a first major side and/or second, opposite major side of the membrane, wherein the capping layer comprises a transition metal doped with an alkali metal or an alkaline earth metal.
19 . The membrane according to claim 16 , further comprising a capping layer providing an outer surface of a first major side and/or second, opposite major side of the membrane, wherein the capping layer comprises an alloy of Mo with at least one other metal.
20 . A pellicle assembly comprising:
the membrane of claim 16 ; and
a frame.