DE20023408U1 - Thermally stable layer system used for reflecting extreme UV rays consists of layer pairs made up of a barrier layer of molybdenum carbide between molybdenum layer and a silicon layer - Google Patents
Thermally stable layer system used for reflecting extreme UV rays consists of layer pairs made up of a barrier layer of molybdenum carbide between molybdenum layer and a silicon layer Download PDFInfo
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- DE20023408U1 DE20023408U1 DE20023408U DE20023408U DE20023408U1 DE 20023408 U1 DE20023408 U1 DE 20023408U1 DE 20023408 U DE20023408 U DE 20023408U DE 20023408 U DE20023408 U DE 20023408U DE 20023408 U1 DE20023408 U1 DE 20023408U1
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- layer
- molybdenum
- silicon
- thermally stable
- barrier
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- 230000004888 barrier function Effects 0.000 title claims abstract description 14
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 title claims abstract description 11
- 229910052710 silicon Inorganic materials 0.000 title claims abstract description 11
- 239000010703 silicon Substances 0.000 title claims abstract description 11
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 title claims abstract description 9
- 229910052750 molybdenum Inorganic materials 0.000 title claims abstract description 9
- 239000011733 molybdenum Substances 0.000 title claims abstract description 9
- QIJNJJZPYXGIQM-UHFFFAOYSA-N 1lambda4,2lambda4-dimolybdacyclopropa-1,2,3-triene Chemical compound [Mo]=C=[Mo] QIJNJJZPYXGIQM-UHFFFAOYSA-N 0.000 title abstract description 4
- 229910039444 MoC Inorganic materials 0.000 title abstract description 4
- 239000000463 material Substances 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 6
- 239000010409 thin film Substances 0.000 claims description 6
- 230000005855 radiation Effects 0.000 claims description 5
- 230000003595 spectral effect Effects 0.000 claims description 5
- JAGQSESDQXCFCH-UHFFFAOYSA-N methane;molybdenum Chemical compound C.[Mo].[Mo] JAGQSESDQXCFCH-UHFFFAOYSA-N 0.000 claims description 2
- 239000000758 substrate Substances 0.000 abstract description 7
- 238000000576 coating method Methods 0.000 description 5
- 238000004544 sputter deposition Methods 0.000 description 5
- 238000010521 absorption reaction Methods 0.000 description 4
- 230000003287 optical effect Effects 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- GALOTNBSUVEISR-UHFFFAOYSA-N molybdenum;silicon Chemical compound [Mo]#[Si] GALOTNBSUVEISR-UHFFFAOYSA-N 0.000 description 2
- 238000005240 physical vapour deposition Methods 0.000 description 2
- YNPNZTXNASCQKK-UHFFFAOYSA-N Phenanthrene Natural products C1=CC=C2C3=CC=CC=C3C=CC2=C1 YNPNZTXNASCQKK-UHFFFAOYSA-N 0.000 description 1
- DGEZNRSVGBDHLK-UHFFFAOYSA-N [1,10]phenanthroline Chemical compound C1=CN=C2C3=NC=CC=C3C=CC2=C1 DGEZNRSVGBDHLK-UHFFFAOYSA-N 0.000 description 1
- 239000011358 absorbing material Substances 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000005566 electron beam evaporation Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000000608 laser ablation Methods 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000037361 pathway Effects 0.000 description 1
- 230000036316 preload Effects 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/708—Construction of apparatus, e.g. environment aspects, hygiene aspects or materials
- G03F7/7095—Materials, e.g. materials for housing, stage or other support having particular properties, e.g. weight, strength, conductivity, thermal expansion coefficient
- G03F7/70958—Optical materials or coatings, e.g. with particular transmittance, reflectance or anti-reflection properties
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/20—Filters
- G02B5/208—Filters for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/20—Filters
- G02B5/28—Interference filters
- G02B5/283—Interference filters designed for the ultraviolet
Abstract
Description
Die Erfindung betrifft ein Verfahren nach dem Oberbegriff des Anspruchs 1.The invention relates to a method according to the preamble of claim 1.
Optische Bauelemente für die Reflexion von Strahlung im extrem ultravioletten Spektralbereich (EUV: 10 nm ... 100 nm) können durch Dünnschichtsysteme realisiert werden, die im allgemeinen aus etwa 40 – 60 auf einem Substrat übereinander liegenden Dünnschichtpaaren bestehen. Eine geringere Anzahl von Paaren führt zu einem niedrigeren Reflexionswert, während eine höhere Anzahl aufgrund der Absorption der Strahlung keine weitere Steigerung des Reflexionswertes ergibt. Ein beispielhafter Wert für die Dicke eines Schichtpaares liegt bei 6,8 nm.Optical components for reflection of radiation in the extremely ultraviolet spectral range (EUV: 10 nm ... 100 nm) through thin-film systems can be realized, which generally consist of about 40-60 one substrate on top of the other lying thin-film pairs consist. A lower number of pairs leads to a lower reflection value, while a higher one Number due to the absorption of the radiation no further increase of the reflection value results. An exemplary value for the thickness of a pair of layers is 6.8 nm.
Die Schichtsysteme werden hauptsächlich durch PVD-Verfahren hergestellt, wobei sowohl Sputter-, Elektronenstrahl-Verdampfungs- als auch Laser-Ablations-Verfahren eingesetzt werden können. CVD-Verfahren wurden ebenfalls erfolgreich zur Herstellung derartiger Schichtsysteme angewendet.The layer systems are mainly through PVD process manufactured, using both sputtering, electron beam evaporation and laser ablation processes can be. CVD processes have also been successful in producing such Layer systems applied.
Ein Dünnschichtpaar besteht im allgemeinen aus zwei Materialien mit unterschiedlichen optischen Konstanten, wobei das eine Material eine möglichst geringe Absorption ("Spacer"), das andere Material dagegen eine große Absorption ("Absorber") aufweisen sollten. Die Auswahl der Dünnschichtmaterialien ist vor allem von der Arbeitswellenlänge des zu realisierenden optischen Bauelementes abhängig (E. Spiller: Low-loss reflection coatings using absorbing materials, Appl. Phys. Lett., 20, S. 365–367, 1972). So sind auf Silizium basierende Dünnschichtsysteme für einen Wellenlängenbereich jenseits der Si-L-Absorptionskante von 12,4 nm bis ca. 35 nm anwendbar. Für diesen Wellenlängenbereich hat sich weiterhin seit über 10 Jahren Molybdän als "Absorber" etabliert, so dass weltweit derzeit fast ausschließlich Mo/Si-Schichtsysteme in diesem Spektralbereich zur Anwendung gelangen (Spiller, SoftX-Ray Optics, SPIE Optical Engenieering Press, Bellingham, 1994).A pair of thin layers generally exists made of two materials with different optical constants, where the one material as possible low absorption ("spacer"), the other material against it a big one Should have absorption ("absorber"). The selection of thin film materials is mainly from the working wavelength of the optical to be realized Component dependent (E. Spiller: Low-loss reflection coatings using absorbing materials, Appl. Phys. Lett., 20, pp. 365-367, 1972). So are silicon-based thin-film systems for one Wavelength range beyond the Si-L absorption edge from 12.4 nm to about 35 nm applicable. For this Wavelength range has continued for over 10 years ago molybdenum was established as an "absorber", so that almost exclusively worldwide Mo / Si layer systems are used in this spectral range (Spiller, SoftX-Ray Optics, SPIE Optical Engineering Press, Bellingham, 1994).
Eine wichtige Charakteristik von im allgemeinen als Spiegel verwendeten Schichtsystemen für den EUV-Spektralbereich ist die maximale Reflexion. Der weltweit höchst gemessene Reflexionswert liegt derzeit bei RMo/Si = 68, 7 % bei 13, 4 nm (C. Montcalm, J. A. Folta, S.P. Vernon: Pathways to high reflectance Mo/Si multilayer coatings for extreme-untraviolet lithography, 4. International Conference on The Physics of X-Ray Multilayer Structures, 1.–5. März 1998, Breckenridge, Colorado, USA).An important characteristic of layer systems generally used as mirrors for the EUV spectral range is the maximum reflection. The world's highest measured reflection value is currently R Mo / Si = 68.7% at 13.4 nm (C. Montcalm, JA Folta, SP Vernon: Pathways to high reflectance Mo / Si multilayer coatings for extreme-untraviolet lithography, 4. International Conference on The Physics of X-Ray Multilayer Structures, March 1-5, 1998, Breckenridge, Colorado, USA).
Dies entspricht etwa 90 % der theoretisch erreichbaren Reflexion Rtheor, die in Abhängigkeit von dem zugrunde liegenden Modell 76,7 % bei 13,4 nm beträgt.This corresponds to approximately 90% of the theoretically achievable reflection R theor , which is 76.7% at 13.4 nm, depending on the underlying model.
Für viele Anwendungen von EUV-Spiegeln ist neben der Reflexion auch eine möglichst hohe Stabilität der Schichtsysteme gegenüber thermischer Belastung erforderlich. Da Mo/Si-Schichtsysteme oberhalb einer Temperatur von ca. 300°C aufgrund von Interdiffusions- und Kristallisationseffekten an den Molybdän-Silizium-Schichtgrenzflächen degradiert werden, sind Systeme dieser Materialpaarung nur bis zu einer maximalen Arbeitstemperatur von 300°C einsetzbar. Bei hohen Photonenenergien oder durch äußere thermische Belastung werden die Schichtsysteme in der Praxis jedoch sehr oft höheren Temperaturen ausgesetzt. Besonders gilt dies beispielsweise für Kollektorspiegel in unmittelbarer Nähe der EUV-Strahlungsquelle. Es wurden bisher zwei Wege verfolgt, Mo/Si-Schichtsysteme auch bei Temperaturen oberhalb 300°C anzuwenden, nämlich:For Many uses of EUV mirrors is in addition to reflection one if possible high stability of the Layer systems opposite thermal load required. Since Mo / Si layer systems above a temperature of approx. 300 ° C due to interdiffusion and Crystallization effects at the molybdenum-silicon layer interfaces are degraded systems of this material pairing are only up to a maximum working temperature of 300 ° C used. At high photon energies or by external thermal In practice, however, the layer systems very often become stressed higher Exposed to temperatures. This applies particularly to collector mirrors, for example close the EUV radiation source. So far, two paths have been followed, Mo / Si layer systems can also be used at temperatures above 300 ° C, namely:
- 1. intensive Substratkühlung und1. intensive substrate cooling and
- 2. Nutzung von ultradünnen Kohlenstoff-Barriereschichten zwischen Molybdän und Silizium zur Vermeidung von Interdiffusions- und Kristallisationseffekten an der Molybdän-Silizium-Grenzfläche (H. Takenaka, T. Kawumara: Thermal stability of Soft X-Ray Mirrors, J. of Eletr. Spectr. and Relat. Phen., 80, S. 381–384, 1996)2. Use of ultra-thin Avoid carbon barrier layers between molybdenum and silicon of interdiffusion and crystallization effects at the molybdenum-silicon interface (H. Takenaka, T. Kawumara: Thermal stability of Soft X-Ray Mirrors, J. of Eletr. Spectr. and Relat. Phen., 80, pp. 381-384, 1996)
Während eine Substratkühlung einen erhöhten apparativen Gesamtaufwand erfordert, weisen Mo/Si-Schichtsysteme mit ultradünnen Kohlenstoff-Barriereschichten eine um ca. 5 % verringerte theoretisch erreichbare maximale Reflexion im Vergleich zu reinen Mo/Si-Schichtsystemen auf.While a substrate cooling an elevated requires total equipment expenditure, have Mo / Si layer systems with ultra thin Carbon barrier layers a theoretically achievable reduced by about 5% maximum reflection compared to pure Mo / Si layer systems.
Es ist daher die Aufgabe der vorliegenden Erfindung, ein thermisch stabiles Schichtsystem zur Reflexion von Strahlung im extremen ultravioletten Spektralbereich, bestehend aus einer Vielzahl von auf einem Substrat übereinander liegenden Dünnschichtpaaren jeweils aus einer Molybdän- und einer Siliziumschicht, wobei zwischen jeweils zwei benachbarten unterschiedlichen Materialschichten eine Barriereschicht angeordnet ist, zu schaffen, dessen Reflexionswert durch die Barriereschicht in geringerem Maße herabgesetzt wird als durch die Kohlenstoffschicht.It is therefore the task of the present Invention, a thermally stable layer system for the reflection of Radiation in the extreme ultraviolet spectral range, consisting from a large number of thin-film pairs lying on top of one another on a substrate each from a molybdenum and a silicon layer, between two adjacent ones different material layers arranged a barrier layer is to create its reflection value through the barrier layer to a lesser extent is degraded than through the carbon layer.
Diese Aufgabe wird erfindungsgemäß gelöst durch das im kennzeichnenden Teil des Anspruchs 1 angegebene Merkmal. Vorteilhafte Weiterbildungen des erfindungsgemäßen Schichtsystems ergeben sich aus den Unteransprüchen.According to the invention, this object is achieved by the feature specified in the characterizing part of claim 1. Advantageous further developments of the layer system according to the invention result itself from the subclaims.
Dadurch, dass die Barriereschicht aus Molybdäncarbid (Mo2C) besteht, wird ein Schichtsystem erhalten, dessen Degradation infolge thermischer Belastung erst bei einer Temperatur oberhalb 500°C beginnt, wobei die durch die Mo2C-Barriereschicht bedingte Herabsetzung des theoretisch erreichbaren Reflexionswertes bei einer Dicke der Barriereschicht von 0,6 nm nur etwa 1 % beträgt.Because the barrier layer consists of molybdenum carbide (Mo 2 C), a layer system is obtained whose degradation due to thermal stress only begins at a temperature above 500 ° C, the reduction in the theoretically achievable reflection value due to the Mo 2 C barrier layer a thickness of the barrier layer of 0.6 nm is only about 1%.
Zur Herstellung von Mo/ Mo2C/Si/Mo2C-Schicht-Systemen werden vorteilhaft PVD-Verfahren angewendet, wobei jeweils zwischen Mobybdän und Silizium eine etwa 0,6 nm dicke Mo2C-Barriereschicht abgeschieden wird. Die Gesamtdicke einer Molybdän- und einer Siliziumschicht beträgt vorzugsweise etwa 6,8 nm. Jedoch sind die Dicke der Einzelschichten sowie das Design des herzustellenden Mo/Mo2C/Si/Mo2C-Schichtsystems abhängig von den Anforderungen, die die jeweils bestimmungsgemäße Anwendung an das Schichtsystem stellt. Die Technologie zur Herstellung der Mo/Mo2C/Si/Mo2C-Schichtsysteme wird vom Beschichtungsprozess bestimmt.PVD processes are advantageously used to produce Mo / Mo 2 C / Si / Mo 2 C layer systems uses an approximately 0.6 nm thick Mo 2 C barrier layer being deposited between mobybdenum and silicon. The total thickness of a molybdenum and a silicon layer is preferably about 6.8 nm. However, the thickness of the individual layers and the design of the Mo / Mo 2 C / Si / Mo 2 C layer system to be produced are dependent on the requirements which the respective intended use to the layer system. The technology for the production of the Mo / Mo 2 C / Si / Mo 2 C layer systems is determined by the coating process.
Zur Beurteilung der thermischen Stabilität eines
Mo/ Mo2C/Si/Mo2C-Schichtsystems
wurden mehrere Mo/Mo2C/Si/Mo2C-Spiegel
für eine
Arbeitswellenlänge
von 13,3 nm realisiert. Die Herstellung dieser Spiegel erfolgte
mit der DC-Magnetron-Sputter-Technologie. Der Beschichtungsprozess
war durch folgende Parameter charakterisiert:
Die bei diesem Schichtsystem maximal gemessene Reflexion betrug R = 59,9 %. Die so hergestellten Mo/Mo2C/Si/Mo2C-Spiegel wurden nach dem Beschichtungsprozess unter Vakuumbedingungen schrittweise bis zu einer Temperatur von 700°C erhitzt. In Auswertung dieser Versuche ergab sich eine thermische Stabilität des Mo/Mo2C/Si/Mo2C-Schichtsystems bis zu einer Temperatur von 500°C.The maximum reflection measured in this layer system was R = 59.9%. The Mo / Mo 2 C / Si / Mo 2 C mirrors thus produced were gradually heated to a temperature of 700 ° C. after the coating process under vacuum conditions. An evaluation of these experiments showed a thermal stability of the Mo / Mo 2 C / Si / Mo 2 C layer system up to a temperature of 500 ° C.
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE20023408U DE20023408U1 (en) | 2000-02-28 | 2000-02-28 | Thermally stable layer system used for reflecting extreme UV rays consists of layer pairs made up of a barrier layer of molybdenum carbide between molybdenum layer and a silicon layer |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2000111547 DE10011547C2 (en) | 2000-02-28 | 2000-02-28 | Thermally stable layer system for reflection of radiation in the extreme ultraviolet spectral range (EUV) |
| DE20023408U DE20023408U1 (en) | 2000-02-28 | 2000-02-28 | Thermally stable layer system used for reflecting extreme UV rays consists of layer pairs made up of a barrier layer of molybdenum carbide between molybdenum layer and a silicon layer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE20023408U1 true DE20023408U1 (en) | 2004-04-01 |
Family
ID=32094539
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE20023408U Expired - Lifetime DE20023408U1 (en) | 2000-02-28 | 2000-02-28 | Thermally stable layer system used for reflecting extreme UV rays consists of layer pairs made up of a barrier layer of molybdenum carbide between molybdenum layer and a silicon layer |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE20023408U1 (en) |
-
2000
- 2000-02-28 DE DE20023408U patent/DE20023408U1/en not_active Expired - Lifetime
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R207 | Utility model specification |
Effective date: 20040506 |
|
| R150 | Term of protection extended to 6 years |
Effective date: 20040401 |
|
| R151 | Term of protection extended to 8 years |
Effective date: 20060518 |
|
| R152 | Term of protection extended to 10 years |
Effective date: 20080502 |
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| R071 | Expiry of right |