Multilayer development for the generation beyond EUV: 6.x nm

Research output: Contribution to conferencePoster

Abstract

Radiation of 6.x nm wavelength is a possible candidate for the next generation of optical lithography aiming at sub 8 nm resolution in single exposure. Construction of multilayer optics based on La and B remains a challenge due to a stronger requirement for layer thickness and interface roughness. The main challenge is to prevent intermixing of the multilayer materials, particularly since individual layer thicknesses (~1.5 nm) are in the same range as the naturally formed compounded interfaces. In recent research we have shown that the formation of La-nitride by N-ion treatment of the La layers reduces compound formation, providing a better optical contrast, thus leading to an increase of the multilayer mirror reflectivity. We also argue that LaN is optically preferred over pure La. Mirrors for 6.x nm require more than 150 periods for a maximum theoretical peak reflectance of 78% for an ideal structure. To deposit such an amount of periods the deposition technique is being optimized. A first optimization of the deposition process has enabled full stack (150 periods) LaN/B4C multilayer mirror samples yielding 47.2% reflectivity at l=6.63 nm (Fig. 1) at near normal incidence. Further optimization of the deposition and nitridation technique is planned aiming to further reduce interface compound formation and roughness value. First of all the magnetron plasma should be optimized in order maximize plasma ion polishing effects and minimize layers intermixture induced by high energy ions and neutrals. Further interface roughness reduction can be achieved by tuning the energy of the atoms being deposited and by low energy ion treatment of the deposited layers
Original languageUndefined
Pages-
Publication statusPublished - 21 Jun 2012
Event13th ASML Technology Conference 2012 - Hotel NH Eindhoven Conference Centre Koningshof, Eindhoven, Netherlands
Duration: 21 Jun 201221 Jun 2012
Conference number: 13

Conference

Conference13th ASML Technology Conference 2012
CountryNetherlands
CityEindhoven
Period21/06/1221/06/12

Keywords

  • METIS-298888

Cite this

Makhotkin, I. A., Zoethout, E., van de Kruijs, R. W. E., Louis, E., Yakunin, A. M., Muellender, S., & Bijkerk, F. (2012). Multilayer development for the generation beyond EUV: 6.x nm. -. Poster session presented at 13th ASML Technology Conference 2012, Eindhoven, Netherlands.
Makhotkin, Igor Alexandrovich ; Zoethout, E. ; van de Kruijs, Robbert Wilhelmus Elisabeth ; Louis, Eric ; Yakunin, A.M. ; Muellender, S. ; Bijkerk, Frederik. / Multilayer development for the generation beyond EUV: 6.x nm. Poster session presented at 13th ASML Technology Conference 2012, Eindhoven, Netherlands.
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abstract = "Radiation of 6.x nm wavelength is a possible candidate for the next generation of optical lithography aiming at sub 8 nm resolution in single exposure. Construction of multilayer optics based on La and B remains a challenge due to a stronger requirement for layer thickness and interface roughness. The main challenge is to prevent intermixing of the multilayer materials, particularly since individual layer thicknesses (~1.5 nm) are in the same range as the naturally formed compounded interfaces. In recent research we have shown that the formation of La-nitride by N-ion treatment of the La layers reduces compound formation, providing a better optical contrast, thus leading to an increase of the multilayer mirror reflectivity. We also argue that LaN is optically preferred over pure La. Mirrors for 6.x nm require more than 150 periods for a maximum theoretical peak reflectance of 78{\%} for an ideal structure. To deposit such an amount of periods the deposition technique is being optimized. A first optimization of the deposition process has enabled full stack (150 periods) LaN/B4C multilayer mirror samples yielding 47.2{\%} reflectivity at l=6.63 nm (Fig. 1) at near normal incidence. Further optimization of the deposition and nitridation technique is planned aiming to further reduce interface compound formation and roughness value. First of all the magnetron plasma should be optimized in order maximize plasma ion polishing effects and minimize layers intermixture induced by high energy ions and neutrals. Further interface roughness reduction can be achieved by tuning the energy of the atoms being deposited and by low energy ion treatment of the deposited layers",
keywords = "METIS-298888",
author = "Makhotkin, {Igor Alexandrovich} and E. Zoethout and {van de Kruijs}, {Robbert Wilhelmus Elisabeth} and Eric Louis and A.M. Yakunin and S. Muellender and Frederik Bijkerk",
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month = "6",
day = "21",
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pages = "--",
note = "null ; Conference date: 21-06-2012 Through 21-06-2012",

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Makhotkin, IA, Zoethout, E, van de Kruijs, RWE, Louis, E, Yakunin, AM, Muellender, S & Bijkerk, F 2012, 'Multilayer development for the generation beyond EUV: 6.x nm' 13th ASML Technology Conference 2012, Eindhoven, Netherlands, 21/06/12 - 21/06/12, pp. -.

Multilayer development for the generation beyond EUV: 6.x nm. / Makhotkin, Igor Alexandrovich; Zoethout, E.; van de Kruijs, Robbert Wilhelmus Elisabeth; Louis, Eric; Yakunin, A.M.; Muellender, S.; Bijkerk, Frederik.

2012. - Poster session presented at 13th ASML Technology Conference 2012, Eindhoven, Netherlands.

Research output: Contribution to conferencePoster

TY - CONF

T1 - Multilayer development for the generation beyond EUV: 6.x nm

AU - Makhotkin, Igor Alexandrovich

AU - Zoethout, E.

AU - van de Kruijs, Robbert Wilhelmus Elisabeth

AU - Louis, Eric

AU - Yakunin, A.M.

AU - Muellender, S.

AU - Bijkerk, Frederik

PY - 2012/6/21

Y1 - 2012/6/21

N2 - Radiation of 6.x nm wavelength is a possible candidate for the next generation of optical lithography aiming at sub 8 nm resolution in single exposure. Construction of multilayer optics based on La and B remains a challenge due to a stronger requirement for layer thickness and interface roughness. The main challenge is to prevent intermixing of the multilayer materials, particularly since individual layer thicknesses (~1.5 nm) are in the same range as the naturally formed compounded interfaces. In recent research we have shown that the formation of La-nitride by N-ion treatment of the La layers reduces compound formation, providing a better optical contrast, thus leading to an increase of the multilayer mirror reflectivity. We also argue that LaN is optically preferred over pure La. Mirrors for 6.x nm require more than 150 periods for a maximum theoretical peak reflectance of 78% for an ideal structure. To deposit such an amount of periods the deposition technique is being optimized. A first optimization of the deposition process has enabled full stack (150 periods) LaN/B4C multilayer mirror samples yielding 47.2% reflectivity at l=6.63 nm (Fig. 1) at near normal incidence. Further optimization of the deposition and nitridation technique is planned aiming to further reduce interface compound formation and roughness value. First of all the magnetron plasma should be optimized in order maximize plasma ion polishing effects and minimize layers intermixture induced by high energy ions and neutrals. Further interface roughness reduction can be achieved by tuning the energy of the atoms being deposited and by low energy ion treatment of the deposited layers

AB - Radiation of 6.x nm wavelength is a possible candidate for the next generation of optical lithography aiming at sub 8 nm resolution in single exposure. Construction of multilayer optics based on La and B remains a challenge due to a stronger requirement for layer thickness and interface roughness. The main challenge is to prevent intermixing of the multilayer materials, particularly since individual layer thicknesses (~1.5 nm) are in the same range as the naturally formed compounded interfaces. In recent research we have shown that the formation of La-nitride by N-ion treatment of the La layers reduces compound formation, providing a better optical contrast, thus leading to an increase of the multilayer mirror reflectivity. We also argue that LaN is optically preferred over pure La. Mirrors for 6.x nm require more than 150 periods for a maximum theoretical peak reflectance of 78% for an ideal structure. To deposit such an amount of periods the deposition technique is being optimized. A first optimization of the deposition process has enabled full stack (150 periods) LaN/B4C multilayer mirror samples yielding 47.2% reflectivity at l=6.63 nm (Fig. 1) at near normal incidence. Further optimization of the deposition and nitridation technique is planned aiming to further reduce interface compound formation and roughness value. First of all the magnetron plasma should be optimized in order maximize plasma ion polishing effects and minimize layers intermixture induced by high energy ions and neutrals. Further interface roughness reduction can be achieved by tuning the energy of the atoms being deposited and by low energy ion treatment of the deposited layers

KW - METIS-298888

M3 - Poster

SP - -

ER -

Makhotkin IA, Zoethout E, van de Kruijs RWE, Louis E, Yakunin AM, Muellender S et al. Multilayer development for the generation beyond EUV: 6.x nm. 2012. Poster session presented at 13th ASML Technology Conference 2012, Eindhoven, Netherlands.