EP0743669A1 - Ion source - Google Patents

Ion source Download PDF

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Publication number
EP0743669A1
EP0743669A1 EP96107544A EP96107544A EP0743669A1 EP 0743669 A1 EP0743669 A1 EP 0743669A1 EP 96107544 A EP96107544 A EP 96107544A EP 96107544 A EP96107544 A EP 96107544A EP 0743669 A1 EP0743669 A1 EP 0743669A1
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EP
European Patent Office
Prior art keywords
anode
housing
gas
ion
outside
Prior art date
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EP96107544A
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German (de)
French (fr)
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EP0743669B1 (en
Inventor
Michael Falz
Rüdiger Wilberg
Wladimir F. Suprjanovitsch
Nikolai K. Kasinski
Wladimir St. Tomal
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Hochvakuum Dresden VEB
VTD Vakuumtechnik Dresden GmbH
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Hochvakuum Dresden VEB
VTD Vakuumtechnik Dresden GmbH
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Priority claimed from DE19531141A external-priority patent/DE19531141C2/en
Application filed by Hochvakuum Dresden VEB, VTD Vakuumtechnik Dresden GmbH filed Critical Hochvakuum Dresden VEB
Publication of EP0743669A1 publication Critical patent/EP0743669A1/en
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J27/00Ion beam tubes
    • H01J27/02Ion sources; Ion guns
    • H01J27/08Ion sources; Ion guns using arc discharge
    • H01J27/14Other arc discharge ion sources using an applied magnetic field
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/06Sources
    • H01J2237/08Ion sources
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/30Electron or ion beam tubes for processing objects
    • H01J2237/31Processing objects on a macro-scale
    • H01J2237/3142Ion plating

Definitions

  • the invention relates to an ion source, in particular for generating ion beams for the ion-assisted deposition of layers in a vacuum, for. B. for the production of optical layers with high performance properties, such as multiple interference layers.
  • the methods without ion support and the methods with ion support are essentially known according to the prior art.
  • the substrates In known coating technologies for the production of optical layers without ion support, the substrates must be heated to temperatures of approximately 300 ° C. Such temperatures are required so that the optical layers have sufficient mechanical properties, such as. B. hardness, abrasion resistance, etc. and the necessary refractive indices.
  • the technological process in such processes is relatively time-consuming because of the required heating of the substrates before the coating process and for cooling the substrates after the coating.
  • the deposited layers generally have a porous, rod-shaped structure that absorbs water vapor from the atmosphere, which leads to undesirable phenomena, such as a shift in the transmission band of layers for optical filters or a change in the spectral curves of the layers over time, the so-called Aging of the layers.
  • Optical layers that are deposited under the influence of ions have refractive indices that are close to those of compact material.
  • the layers are almost non-porous and dense in structure.
  • the layers are largely stable to atmospheric influences.
  • the methods for ion-supported layer deposition use different types of ion sources, e.g. Penning sources, sources with acceleration grids as well as without and with additional magnetic field on the front side, etc.
  • ion sources e.g. Penning sources, sources with acceleration grids as well as without and with additional magnetic field on the front side, etc.
  • the US 48 62 032 describes an ion source for generating a low-energy ion beam in the magnetic field.
  • the ion source has a coil, a cylindrical anode, a cathode and a device for introducing and distributing the working gas for ion formation within a housing.
  • the pole ends of the magnet system are located on the two axial sides of the housing, a magnetic field being generated which is directed from the anode to the cathode.
  • the anode has a central conical bore, the larger diameter of which is in the direction of the substrates.
  • the diameter of the ion beam exit opening in the housing, which is directed towards the substrates, is larger than the large diameter of the conical bore in the anode.
  • the anode is not cooled. This can lead to dangerous overheating of the construction elements of the ion source, even with low supplied powers and even without continuous operation. As a result, there is increased gas release, which worsens the working vacuum and has a negative influence on the characteristics of the optical layers.
  • the gas distributor is designed within the housing of the ion source in the form of a plate with a series of holes and is located between the magnet coil and the anode.
  • the gas is introduced through an opening in the housing near the solenoid.
  • Part of the gas enters the conical hole of the anode on the small diameter side through holes in the gas distributor and through an annular gap. Since the magnetic field is strongest here, high plasma densities are achieved, and dusting effects can lead to undesirably strong erosion of the gas distributor and the anode.
  • the other part of the gas flows through the housing between the inside walls of the source and special rings between which the anode is attached.
  • This gas bypasses the zone of gas ionization, which leads to an ineffective use of the working gas in the plasma generation and ultimately to an increase in the working pressure in the vacuum chamber.
  • the operating voltage of the gas discharge is set.
  • the cathode is located on the other side of the discharge zone and is designed as an open tungsten filament, which is located within the zone of the spread of the ion beam.
  • the cathode generates the electrons for gas ionization and at the same time for the neutralization of the ion beam by thermal electron emission.
  • the tungsten filament is a source of tungsten atoms through thermal evaporation and also through atomization in the ion beam of the ion source, since the tungsten filament is located directly in the zone of the ion beam with high density.
  • This mechanism makes the cathode an additional source of contamination in the ion-supported layers, especially optical layers. Furthermore, the life of the cathode is shortened and the operating parameters often have to be readjusted so that the emission capability is maintained.
  • the sources shown for impurities in the ion-assisted layer deposition according to the prior art are mostly uncritical for simple, even simple optical, coatings.
  • high-quality layer deposits in particular in the case of multiple layers with 15 to 30 or more ⁇ / 4 layers and coating times of more than two hours, such contaminations lead to faulty layers.
  • the absorption coefficient for optical layers in the UV range increases strongly as a result of contamination of the layers by metal atoms of components of the ion source.
  • the invention has for its object to provide an ion source, which in industrial vacuum systems for the production of ion-supported layers with high purity, in particular of optical layers, for. B. multiple interference layers can be used.
  • the dusting of material from the ion source should be reduced in such a way that the incorporation of appropriate atoms in the layers is largely avoided.
  • the deposited layers should have a nearly pore-free and dense structure and be stable against atmospheric influences.
  • the required substrate temperatures should be low and the stability of the technological parameters of the ion source should be high.
  • the ion source according to the invention then has a housing which encloses an essentially closed space in which a magnet system is integrated, an anode and a gas guiding device for a working gas.
  • the ion current leaves the ion source in a beam from the coaxial ion beam exit opening in the direction of the substrates.
  • the gas guiding device with a gas inlet and an orifice system is intended to intensively ionize the gas flow at the anode.
  • the ion source is characterized u. a. characterized in that the anode has an inner diameter which is larger than the diameter of the ion beam outlet opening.
  • the direct path of dusted material particles from the anode to the substrates is essentially interrupted and such particles cannot get into the actual working area of the ion beam on the substrate.
  • the arrangement of the cathode which is mounted outside the zone of propagation of the ion beam and is shielded from all sides, except for the side facing the ion exit from the ion source.
  • the ion source can be equipped with an additional magnetic field source, which is located outside the housing of the anode coaxially to the main magnetic field source, the direction of the fields matching.
  • FIG. 1 shows schematically in Figure 1 an ion source according to an embodiment I according to an embodiment in a side section.
  • FIG. 2 shows a top view of FIG. 1.
  • FIG. 3 shows as embodiment II a variant of the embodiment of the ion source according to embodiment I with an additional magnetic coil.
  • the ion source shown in FIGS. 1 and 2 has, in a housing 1, an anode 2, a magnetic coil 3 and between them an aperture system consisting of an aperture plate 4 and an aperture ring 5.
  • the ion beam emanating from the anode 2 leaves the ion source via the ion beam exit opening 6.
  • the anode 2 is made of a ring-shaped thin-walled tube made of stainless steel.
  • the inner diameter of the anode 2 is larger than the diameter of the ion beam outlet opening 6.
  • the tube of the ring-shaped anode 2 is flowed through during the operation of cooling water, so that the heat can be removed from the anode 2 very effectively. Overheating due to the discharge processes are avoided. The performance of the ion source can thus be increased significantly.
  • the special design of the anode 2 and the aperture system leads to a reduction in the plasma density above the aperture plate 4.
  • the sputtering of the metallic aperture plate 4, as the main source of contamination of the ion-supported layers in the prior art, is thereby avoided or substantially reduced.
  • the geometric arrangement and design of the anode 2, with its position outside the zone have a similar effect with a strong magnetic field, and the reduction of the surface, which is directed towards the discharge area, only a small amount of erosion through the discharge processes, furthermore the direct impact of atomized material particles of the anode 2 on the substrates and thus the contamination of the ion-supported deposited layers the ion beam exit opening 6, which acts as a diaphragm, is impeded.
  • the introduction of the working gas into the ion source takes place via a gas inlet 7 at the bottom 8 of the housing in the area of the magnetic coil 3.
  • the large volume of the housing space with the magnetic coil 3 calms the gas flow and the flowing gas simultaneously cools the magnetic coil 3.
  • the working gas is fed into the discharge space with the anode 2 uniformly over the entire circumference of the annular gap between the orifice plate 4 and the orifice ring 5.
  • the orifice system has the effect that a uniform flow of the working gas is concentrated in the interior between the anode 2 and the ion beam.
  • Exit opening 6 the discharge region of the ion source, is passed.
  • the aperture ring 5 is attached to the inner wall of the housing 1 in a substantially gas-tight manner.
  • the aperture plate 4 is held at a distance from the aperture ring 5 via insulators in such a way that the working gas reaches the aperture system in the discharge region of the ion source without eddy formation.
  • the design of the anode 2 does not affect the uniformity of the working gas flow.
  • the diaphragm ring 5 is located outside the area of the magnetic field, and there is no gas discharge between it and the anode 2.
  • the magnet coil 3 is arranged centrally on the bottom 8 of the housing 1 and the housing 1 acts as part of the Magnet system, wherein the bottom 8 is a first pole 9 and the housing cover 10 with the ion beam exit opening 6 is the second pole 11.
  • the cathode 12 a tungsten filament, is located on the housing cover 10 and outside the housing 1 of the ion source.
  • the cathode 12 is arranged in a parallel position to the housing cover 10 outside the optical line between the anode 2 and the ion beam outlet opening 6 and covered with a screen 13 such that only the side facing the ion beam is open.
  • the cathode 12 is thus outside the zone of the spread of the ion beams and is therefore not subjected to direct erosion by impinging ions. In this way, the service life of the cathode 12 is significantly extended.
  • the screen 13 above the cathode 12 primarily prevents the escape of tungsten atoms from the cathode 12 and the subsequent contamination of the deposited layers with them.
  • the arrangement of the cathode 12, the presence of the screen 13 and the position to the anode 2 ensures the maintenance of a stable thermal electron emission and the formation of a plasma discharge between the cathode 12 and the anode 2, as a result of which under the action of the magnetic field, in particular on the second Pole 11 at the ion beam exit opening 6, an ion beam is generated in the direction of the substrates.
  • the working pressure in the vacuum system can during of the ion-assisted coating process can be kept as low as necessary.
  • a dark cathode space is created between the screen 13 and the water supply and the supply of the positive anode potential, which protects against the occurrence of an undesired gas discharge between the supply lines and the housing of the vacuum chamber (negative potential).
  • FIG. 3 shows, as embodiment II, a variant of the ion source according to embodiment I (same item numbers), in which a second magnet coil 15 is arranged outside the housing 1 of the ion source coaxially to the magnet coil 3 and axially in the region of the anode 2.
  • a second magnet coil 15 is arranged outside the housing 1 of the ion source coaxially to the magnet coil 3 and axially in the region of the anode 2.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Electron Sources, Ion Sources (AREA)

Abstract

The ion source has a pref. cylindrical housing (1) contg. an anode (2), magnetic coil (3) and an aperture system forming part of a gas conducting system. The coil is centrally mounted on one axial end of the housing so its magnetic field diverges towards the anode, which is outside the strong field region. The other housing end is a cover with a central ion outlet (6). The anode is an annular water-cooled tube anode with inner dia. greater than the ion outlet, which forms a stop. The gas conducting system has a working gas inlet in the base (8) or housing casing near the coil. The gas stop system has a stop ring (5) facing the anode with a gas tight attachment to the inner housing wall and a central stop plate (4)facing the coil. A cathode (12) outside the housing is mounted outside the optical line between the anode and ion outlet, pref. on the housing top (10).

Description

Die Erfindung betrifft eine Ionenquelle, insbesondere zur Erzeugung von Ionenstrahlen für die ionengestützte Abscheidung von schichten im Vakuum, z. B. zur Herstellung von optischen schichten mit hohen Gebrauchseigenschaften, wie Mehrfach-Interferenzschichten.The invention relates to an ion source, in particular for generating ion beams for the ion-assisted deposition of layers in a vacuum, for. B. for the production of optical layers with high performance properties, such as multiple interference layers.

Zur Herstellung von optischen Schichten mittels Schichtabscheidung im Vakuum sind nach dem Stand der Technik im wesentlichen die Verfahren ohne Ionenunterstützung und die Verfahren mit Ionenunterstützung bekannt. Bei bekannten Beschichtungstechnologien zur Herstellung optischer Schichten ohne Ionenunterstützung ist eine Erwärmung der Substrate bis auf Temperaturen von ca. 300°C notwendig. Derartige Temperaturen sind erforderlich, damit die optischen Schichten ausreichende mechanische Eigenschaften, wie z. B. Härte, Abriebfestigkeit usw. sowie die notwendigen Brechzahlen aufweisen. Der technologische Prozeß ist bei derartigen Verfahren wegen der erforderlichen Erwärmung der Substrate vor dem Beschichtungsprozeß und zur Abkühlung der Substrate nach der Beschichtung relativ zeitaufwendig. Die abgeschiedenen Schichten weisen in der Regel eine poröse, stabförmige Struktur auf, die Wasserdampf aus der Atmosphäre absorbiert, was zu unerwünschten Erscheinungen, wie eine Verschiebung des Transmissionsbandes von schichten für optische Filter oder eine Veränderung der Spektralkurven der Schichten im Laufe der Zeit, der sogenannten Alterung der Schichten, führt.For the production of optical layers by means of layer deposition in a vacuum, the methods without ion support and the methods with ion support are essentially known according to the prior art. In known coating technologies for the production of optical layers without ion support, the substrates must be heated to temperatures of approximately 300 ° C. Such temperatures are required so that the optical layers have sufficient mechanical properties, such as. B. hardness, abrasion resistance, etc. and the necessary refractive indices. The technological process in such processes is relatively time-consuming because of the required heating of the substrates before the coating process and for cooling the substrates after the coating. The deposited layers generally have a porous, rod-shaped structure that absorbs water vapor from the atmosphere, which leads to undesirable phenomena, such as a shift in the transmission band of layers for optical filters or a change in the spectral curves of the layers over time, the so-called Aging of the layers.

Bei Verfahren zur Abscheidung optischer schichten mit Ionenunterstützung werden die angeführten Mängel weitgehend vermieden. Optische Schichten, die unter Ioneneinfluß abgeschieden werden, weisen Brechzahlen auf, die nahe den von Kompaktmaterial liegen. Die schichten sind nahezu porenfrei und dicht in der Struktur. Den atmosphärischen Einwirkungen gegenüber sind die Schichten weitgehend stabil.In the case of processes for the deposition of optical layers with ion support, the deficiencies mentioned are largely avoided. Optical layers that are deposited under the influence of ions have refractive indices that are close to those of compact material. The layers are almost non-porous and dense in structure. The layers are largely stable to atmospheric influences.

Von besonderer Bedeutung ist es, daß ionengestützte Abscheidungsverfahren keine gesonderte Erwärmung der Substrate erforderlich machen, was die Produktivität von entsprechenden Beschichtungsausrüstungen wesentlich erhöht.It is of particular importance that ion-assisted deposition processes do not require separate heating of the substrates, which significantly increases the productivity of the corresponding coating equipment.

Die Verfahren zur ionengestützten Schichtabscheidung nutzen verschiedene Typen von Ionenquellen, z.B. Penningquellen, Quellen mit Beschleunigungsgittern sowie Ohne und mit Zusatzmagnetfeld an der Stirnseite u.a.The methods for ion-supported layer deposition use different types of ion sources, e.g. Penning sources, sources with acceleration grids as well as without and with additional magnetic field on the front side, etc.

Die US 48 62 032 beschreibt eine Ionenquelle zur Erzeugung eines niederenergetischen Ionenstrahles im Stirnmagnetfeld. Die Ionenquelle weist innerhalb eines Gehäuses eine Spule, eine zylindrische Anode, eine Katode sowie eine Vorrichtung zur Einleitung und Verteilung des Arbeitsgases für die Ionenausbildung auf. Die Polenden des Magnetsystemes befinden sich auf den beiden axialen Seiten des Gehäuses, wobei ein Magnetfeld erzeugt wird, das von der Anode zur Katode gerichtet ist.The US 48 62 032 describes an ion source for generating a low-energy ion beam in the magnetic field. The ion source has a coil, a cylindrical anode, a cathode and a device for introducing and distributing the working gas for ion formation within a housing. The pole ends of the magnet system are located on the two axial sides of the housing, a magnetic field being generated which is directed from the anode to the cathode.

Die Anode besitzt eine zentrische konische Bohrung, deren größerer Durchmesser sich in Richtung der Substrate befindet. Der Durchmesser der Ionenstrahl-Austrittsöffnung im Gehäuse, die zu den Substraten hin gerichtet ist, ist größer als der große Durchmesser der konischen Bohrung in der Anode. Dadurch kann unerwünscht zerstäubtes Material der Anode vom Ionenstrahl ungehindert zur optischen Schicht auf den Substraten befördert werden.The anode has a central conical bore, the larger diameter of which is in the direction of the substrates. The diameter of the ion beam exit opening in the housing, which is directed towards the substrates, is larger than the large diameter of the conical bore in the anode. As a result, undesired atomized material of the anode can be conveyed unhindered by the ion beam to the optical layer on the substrates.

Die Anode wird nicht gekühlt. Das kann, bereits bei niedrigen zugeführten Leistungen und auch ohne Dauerbetrieb, zu gefährlichen Überhitzungen der Konstruktionselemente der Ionenquelle führen. In der Folge kommt es zur erhöhten Gasfreisetzung, was das Arbeitsvakuum verschlechtert und die Kennwerte der optischen Schichten negativ beeinflußt.The anode is not cooled. This can lead to dangerous overheating of the construction elements of the ion source, even with low supplied powers and even without continuous operation. As a result, there is increased gas release, which worsens the working vacuum and has a negative influence on the characteristics of the optical layers.

Der Gasverteiler ist innerhalb des Gehäuses der Ionenquelle in Form einer Platte mit einer Reihe von Bohrungen ausgeführt und befindet sich zwischen der Magnetspule und der Anode. Das Gas wird durch eine Öffnung im Gehäuse nahe der Magnetspule eingeleitet.The gas distributor is designed within the housing of the ion source in the form of a plate with a series of holes and is located between the magnet coil and the anode. The gas is introduced through an opening in the housing near the solenoid.

Ein Teil des Gases tritt durch Bohrungen des Gasverteilers und über einen ringförmigen Spalt in die konische Bohrung der Anode auf der Seite mit dem kleinen Durchmesser ein. Da das Magnetfeld hier am stärksten ist, werden hohe Plasmadichten erreicht, und es kann durch Abstäubungseffekte zu einer unerwünscht starken Erosion des Gasverteilers und der Anode kommen.Part of the gas enters the conical hole of the anode on the small diameter side through holes in the gas distributor and through an annular gap. Since the magnetic field is strongest here, high plasma densities are achieved, and dusting effects can lead to undesirably strong erosion of the gas distributor and the anode.

Der andere Teil des Gases strömt zwischen den Innenwänden der Quelle und speziellen Ringen, zwischen denen die Anode befestigt ist, durch das Gehäuse. Dabei umgeht dieses Gas die Zone der Gasionisation, was zu einer uneffektiven Ausnutzung des Arbeitsgases bei der Plasmaerzeugung und im Endeffekt zur Erhöhung des Arbeitsdruckes in der Vakuumkammer führt. Durch die Regelung des Spaltes zwischen den Ringen und der Innenwand des Gehäuses der Ionenquelle wird die Brennspannung der Gasentladung eingestellt.The other part of the gas flows through the housing between the inside walls of the source and special rings between which the anode is attached. This gas bypasses the zone of gas ionization, which leads to an ineffective use of the working gas in the plasma generation and ultimately to an increase in the working pressure in the vacuum chamber. By regulating the gap between the rings and the inner wall of the housing of the ion source, the operating voltage of the gas discharge is set.

Die Katode befindet sich auf der anderen Seite der Entladungszone und ist als offene Wolframwendel ausgeführt, die sich innerhalb der Zone der Ausbreitung des Ionenstrahles befindet. Die Katode erzeugt durch thermische Elektronenemission die Elektronen für die Gasionisation und gleichzeitig für die Neutralisation des Ionenstrahls.The cathode is located on the other side of the discharge zone and is designed as an open tungsten filament, which is located within the zone of the spread of the ion beam. The cathode generates the electrons for gas ionization and at the same time for the neutralization of the ion beam by thermal electron emission.

Dabei ist die Wolframwendel eine Quelle für Wolframatome durch thermische Verdampfung und auch durch Zerstäubung im Ionenstrahl der Ionenquelle, da sich die Wolframwendel unmittelbar in der Zone des Ionenstrahls mit hoher Dichte befindet. Durch diesen Mechanismus ist die Katode eine zusätzliche Quelle für Verunreinigungen in den ionengestützt abgeschiedenen Schichten, insbesondere bei optischen Schichten. Des weiteren wird die Lebensdauer der Katode verkürzt und die Betriebsparameter müssen häufig nachgeregelt werden, damit die Emissionssfähigkeit erhalten bleibt.The tungsten filament is a source of tungsten atoms through thermal evaporation and also through atomization in the ion beam of the ion source, since the tungsten filament is located directly in the zone of the ion beam with high density. This mechanism makes the cathode an additional source of contamination in the ion-supported layers, especially optical layers. Furthermore, the life of the cathode is shortened and the operating parameters often have to be readjusted so that the emission capability is maintained.

Die dargestellten Quellen für Verunreinigungen bei der ionengestützten Schichtabscheidung nach dem Stand der Technik sind bei einfachen, auch einfachen optischen, Beschichtungen meist unkritisch. Bei hochwertigen Schichtabscheidungen, insbesondere bei Mehrfach-Schichten mit 15 bis 30 und mehr λ/4-Schichten sowie Beschichtungszeiten von über zwei Stunden, führen derartige Verunreinigungen zu fehlerhaften Schichten. Z. B. wächst der Absorbtionskoeffizient für optische Schichten im UV Bereich in Folge der Verunreinigungen der schichten durch Metallatome von Bauelementen der Ionenquelle stark an.The sources shown for impurities in the ion-assisted layer deposition according to the prior art are mostly uncritical for simple, even simple optical, coatings. In the case of high-quality layer deposits, in particular in the case of multiple layers with 15 to 30 or more λ / 4 layers and coating times of more than two hours, such contaminations lead to faulty layers. For example, the absorption coefficient for optical layers in the UV range increases strongly as a result of contamination of the layers by metal atoms of components of the ion source.

Der Erfindung liegt die Aufgabe zugrunde, eine Ionenquelle zu schaffen, die in industriellen Vakuumanlagen zur Herstellung ionengestützt abgeschiedener Schichten mit hoher Reinheit, insbesondere von optischen Schichten, z. B. Mehrfach-Interferenzschichten, eingesetzt werden kann. Die Abstäubung von Material der Ionenquelle soll derart vermindert werden, daß der Einbau entsprechender Atome in die Schichten weitgehend vermieden wird. Die abgeschiedenen schichten sollen eine nahezu porenfreie und dichte Struktur aufweisen und stabil gegenüber atmosphärischen Einwirkungen sein. Die erforderlichen Substrattemperaturen sollen niedrig und die Stabilität der technologischen Parameter der Ionenquelle hoch sein.The invention has for its object to provide an ion source, which in industrial vacuum systems for the production of ion-supported layers with high purity, in particular of optical layers, for. B. multiple interference layers can be used. The dusting of material from the ion source should be reduced in such a way that the incorporation of appropriate atoms in the layers is largely avoided. The deposited layers should have a nearly pore-free and dense structure and be stable against atmospheric influences. The required substrate temperatures should be low and the stability of the technological parameters of the ion source should be high.

Die Erfindung löst die Aufgabe durch die Merkmale des Anspruchs 1. Eine Weiterbildung der Erfindung ist im Unteranspruch gekennzeichnet.The invention solves the problem by the features of claim 1. A further development of the invention is characterized in the subclaim.

Die erfindungsgemäße Ionenquelle weist danach ein Gehäuse auf, welches einen im wesentlichen abgeschlossenen Raum umschließt, in dem ein Magnetsystem integriert ist, eine Anode und eine Gasleiteinrichtung für ein Arbeitsgas vorhanden. Der Ionenstrom verläßt die Ionenquelle strahlförmig aus der koaxialen Ionenstrahl-Austrittsöffnung in Richtung der Substrate.The ion source according to the invention then has a housing which encloses an essentially closed space in which a magnet system is integrated, an anode and a gas guiding device for a working gas. The ion current leaves the ion source in a beam from the coaxial ion beam exit opening in the direction of the substrates.

Von besonderer Bedeutung ist die Ausbildung der Anode und deren geometrische Anordnung zur Ionenstrahl-Austrittsöffnung und zur außerhalb des Gehäuses angeordneten Katode.Of particular importance is the design of the anode and its geometrical arrangement with respect to the ion beam outlet opening and the cathode arranged outside the housing.

Diese spezifische Lösung unterbindet weitgehend die Verunreinigung der ionengestützt abgeschiedenen Schichten mit unerwünscht zerstäubten Materialteilchen der Ionenquelle. Die Gasleiteinrichtung mit einem Gaseinlaß und einem Blendensystem soll eine intensive Ionisierung des Gas-stromes an der Anode bewirken.This specific solution largely prevents contamination of the ion-supported layers with undesirably atomized material particles from the ion source. The gas guiding device with a gas inlet and an orifice system is intended to intensively ionize the gas flow at the anode.

Die Ionenquelle zeichnet sich u. a. dadurch aus, daß die Anode einen Innendurchmesser aufweist, der größer als der Durchmesser der Ionenstrahl-Austrittsöffnung ist. Dadurch wird der direkte Weg von abgestäubten Materialteilchen von der Anode zu den Substraten im wesentlichen unterbrochen und derartige Teilchen können nicht in den eigentlichen Arbeitsbereich des Ionenstrahls am Substrat gelangen. Von besonderer Bedeutung ist auch die Anordnung der Katode, die außerhalb der Ausbreitungszone des Ionenstrahles montiert und von allen Seiten abgeschirmt ist, ausgenommen der Seite, die dem Ionenaustritt aus der Ionenquelle zugewandt ist.The ion source is characterized u. a. characterized in that the anode has an inner diameter which is larger than the diameter of the ion beam outlet opening. As a result, the direct path of dusted material particles from the anode to the substrates is essentially interrupted and such particles cannot get into the actual working area of the ion beam on the substrate. Also of particular importance is the arrangement of the cathode, which is mounted outside the zone of propagation of the ion beam and is shielded from all sides, except for the side facing the ion exit from the ion source.

Nach Anspruch 2 kann die Ionenquelle mit einer zusätzlichen Magnetfeldqelle ausgerüstet sein, die sich außerhalb des Gehäuses der Anode koaxial zur Hauptmagnetfeldquelle befindet, wobei die Richtung der Felder übereinstimmen.According to claim 2, the ion source can be equipped with an additional magnetic field source, which is located outside the housing of the anode coaxially to the main magnetic field source, the direction of the fields matching.

Die Erfindung soll nachstehend an zwei Ausführungsbeispielen näher erläutert werden.The invention will be explained in more detail below using two exemplary embodiments.

Die Zeichnung zeigt in Figur 1 schematisch eine erfindungsgemäße Ionenquelle nach einem Ausführungsbeispiel I in einem Seitenschnitt.
Figur 2 zeigt eine Draufsicht von Figur 1.
Figur 3 zeigt als Ausführungsbeispiel II eine Variante der Ausführung der Ionenquelle nach Ausführungsbeispiel I mit einer zusätzlichen Magnetspule.
The drawing shows schematically in Figure 1 an ion source according to an embodiment I according to an embodiment in a side section.
FIG. 2 shows a top view of FIG. 1.
FIG. 3 shows as embodiment II a variant of the embodiment of the ion source according to embodiment I with an additional magnetic coil.

Ausführungsbeispiel IEmbodiment I

Die in Figur 1 und 2 dargestellt Ionenquelle weist in einem Gehäuse 1 eine Anode 2, eine Magnetspule 3 und zwischen beiden ein Blendensystem, bestehend aus einer Blendenplatte 4 und einem Blendenring 5, auf. Der von der Anode 2 ausgehende Ionenstrahl verläßt die Ionenquelle über die Ionenstrahl-Austrittsöffnung 6.The ion source shown in FIGS. 1 and 2 has, in a housing 1, an anode 2, a magnetic coil 3 and between them an aperture system consisting of an aperture plate 4 and an aperture ring 5. The ion beam emanating from the anode 2 leaves the ion source via the ion beam exit opening 6.

Die Anode 2 ist aus einem ringförmig gebogenen dünnwandigen Rohr aus rostfreiem Stahl hergestellt. Der Innendurchmesser der Anode 2 ist größer als der Durchmesser der Ionenstrahl-Austrittsöffnung 6. Das Rohr der ringförmigen Anode 2 wird im Betrieb von Kühlwasser durchflossen, wodurch sehr effektiv die Wärme von der Anode 2 abgeführt werden kann. Überhitzungen aufgrund der Entladungsprozesse werden vermieden. Die Leistung der Ionenquelle kann somit wesentlich erhöht werden.The anode 2 is made of a ring-shaped thin-walled tube made of stainless steel. The inner diameter of the anode 2 is larger than the diameter of the ion beam outlet opening 6. The tube of the ring-shaped anode 2 is flowed through during the operation of cooling water, so that the heat can be removed from the anode 2 very effectively. Overheating due to the discharge processes are avoided. The performance of the ion source can thus be increased significantly.

Die spezielle Ausbildung der Anode 2 und des Blendensystems führt zu einer Verringerung der Plasmadichte über der Blendenplatte 4. Die Zerstäubung der metallischen Blendenplatte 4, als Hauptquelle von Verunreinigungen der ionengestützt abgeschiedenen Schichten beim Stand der Technik, wird dadurch vermieden oder wesentlich gesenkt. In ähnlicher Weise bewirkt die geometrische Anordnung und Ausbildung der Anode 2, mit ihrer Lage außerhalb der Zone mit starkem Magnetfeld, und die Verringerung der Oberfläche, die zum Entladungsgebiet gerichtet ist, nur im geringen Maße eine Erosion durch die Entladungsprozesse, Des weiteren wird das direkte Auftreffen von zerstäubten Materialteilchen der Anode 2 auf die Substrate und damit die Verunreinigung der ionengestützt abgeschiedenen schichten durch die als Blende wirkende Ionenstrahl-Austrittsöffnung 6 behindert.The special design of the anode 2 and the aperture system leads to a reduction in the plasma density above the aperture plate 4. The sputtering of the metallic aperture plate 4, as the main source of contamination of the ion-supported layers in the prior art, is thereby avoided or substantially reduced. The geometric arrangement and design of the anode 2, with its position outside the zone, have a similar effect with a strong magnetic field, and the reduction of the surface, which is directed towards the discharge area, only a small amount of erosion through the discharge processes, furthermore the direct impact of atomized material particles of the anode 2 on the substrates and thus the contamination of the ion-supported deposited layers the ion beam exit opening 6, which acts as a diaphragm, is impeded.

Die Einleitung des Arbeitsgases in die Ionenquelle erfolgt über einen Gaseinlaß 7 am Boden 8 des Gehäuses im Bereich der Magnetspule 3. Durch das große Volumen des Gehäuseraumes mit der Magnetspule 3 wird die Gasströmung beruhigt und das strömende Gas kühlt gleichzeitig die Magnetspule 3.The introduction of the working gas into the ion source takes place via a gas inlet 7 at the bottom 8 of the housing in the area of the magnetic coil 3. The large volume of the housing space with the magnetic coil 3 calms the gas flow and the flowing gas simultaneously cools the magnetic coil 3.

Die Zuführung des Arbeitsgases in den Entladungsraum mit der Anode 2 erfolgt gleichmäßig über den gesamten Umfang des Ringspaltes zwischen der Blendenplatte 4 und dem Blendenring 5. Das Blendensystem bewirkt, daß ein gleichmäßiger Strom des Arbeitsgases konzentriert in den Innenbereich zwischen der Anode 2 und der Ionenstrahl-Austrittsöffnung 6, dem Entladungsgebiet der Ionenquelle, geleitet wird. Der Blendenring 5 ist im wesentlichen gasdicht an der Innenwand des Gehäuses 1 befestigt. Die Blendenplatte 4 ist über Isolatoren derart auf Abstand zum Blendenring 5 gehaltert, daß das Arbeitsgas das Blendensystem ohne Wirbelbildung in das Entladungsgebiet der Ionenquelle gelangt. Die Gestaltung der Anode 2 beeinflußt die Gleichmäßigkeit des Arbeitsgasstromes nicht.The working gas is fed into the discharge space with the anode 2 uniformly over the entire circumference of the annular gap between the orifice plate 4 and the orifice ring 5. The orifice system has the effect that a uniform flow of the working gas is concentrated in the interior between the anode 2 and the ion beam. Exit opening 6, the discharge region of the ion source, is passed. The aperture ring 5 is attached to the inner wall of the housing 1 in a substantially gas-tight manner. The aperture plate 4 is held at a distance from the aperture ring 5 via insulators in such a way that the working gas reaches the aperture system in the discharge region of the ion source without eddy formation. The design of the anode 2 does not affect the uniformity of the working gas flow.

Der Blendenring 5 befindet sich außerhalb des Gebietes des Magnetfeldes, und es entsteht keine Gasentladung zwischen diesem und der Anode 2.The diaphragm ring 5 is located outside the area of the magnetic field, and there is no gas discharge between it and the anode 2.

Die Magnetspule 3 ist zentrisch am Boden 8 des Gehäuses 1 angeordnet und das Gehäuse 1 wirkt als Teil des Magnetsystems, wobei der Boden 8 ein erster Pol 9 ist und die Gehäuseabdeckung 10 mit der Ionenstrahl-Austrittsöffnung 6 ist der zweite Pol 11.The magnet coil 3 is arranged centrally on the bottom 8 of the housing 1 and the housing 1 acts as part of the Magnet system, wherein the bottom 8 is a first pole 9 and the housing cover 10 with the ion beam exit opening 6 is the second pole 11.

Die Katode 12, ein Wolframwendel, befindet sich im Ausführungsbeispiel auf der Gehäuseabdeckung 10 und außerhalb des Gehäuses 1 der Ionenquelle. Die Katode 12 ist dabei in paralleler Lage zur Gehäuseabdeckung 10 außerhalb der optischen Linie zwischen der Anode 2 und der Ionenstrahl-Austrittsöffnung 6 angeordnet und mit einem Schirm 13 derart abgedeckt, daß lediglich die dem Ionenstrahl zugewandte Seite offen ist. Seitlich am Gehäuse 1 befindet sich noch eine Abdeckung 14, die die nicht näher dargestellte Kühlwasserzuführung und die Stromzuführung zur Anode 2 abdeckt.In the exemplary embodiment, the cathode 12, a tungsten filament, is located on the housing cover 10 and outside the housing 1 of the ion source. The cathode 12 is arranged in a parallel position to the housing cover 10 outside the optical line between the anode 2 and the ion beam outlet opening 6 and covered with a screen 13 such that only the side facing the ion beam is open. On the side of the housing 1 there is also a cover 14, which covers the cooling water supply (not shown) and the power supply to the anode 2.

Die Katode 12 befindet sich damit außerhalb der Zone der Ausbreitung der Ionenstrahlen und wird somit keiner direkten Erosion durch auftreffende Ionen unterworfen. Auf diese Weise wird die Standzeit der Katode 12 wesentlich verlängert.The cathode 12 is thus outside the zone of the spread of the ion beams and is therefore not subjected to direct erosion by impinging ions. In this way, the service life of the cathode 12 is significantly extended.

Der Schirm 13 über Katode 12 verhindert vor allem das Entweichen von Wolframatomen aus der Katode 12 und die nachfolgende Verunreinigung der abgeschiedenen Schichten mit diesen.The screen 13 above the cathode 12 primarily prevents the escape of tungsten atoms from the cathode 12 and the subsequent contamination of the deposited layers with them.

Die Anordnung der Katode 12, das Vorhandensein des Schirmes 13 und die Lage zur Anode 2 sichert die Aufrechterhaltung einer stabilen thermischer Elektronenemission und die Ausbildung einer Plasmaentladung zwischen der Katode 12 und der Anode 2, in deren Folge unter der Wirkung des Magnetfeldes, insbesondere am zweiten Pol 11 an der Ionenstrahl-Austrittsöffnung 6, ein Ionenstrahl in Richtung der Substrate erzeugt wird.The arrangement of the cathode 12, the presence of the screen 13 and the position to the anode 2 ensures the maintenance of a stable thermal electron emission and the formation of a plasma discharge between the cathode 12 and the anode 2, as a result of which under the action of the magnetic field, in particular on the second Pole 11 at the ion beam exit opening 6, an ion beam is generated in the direction of the substrates.

Der Arbeitsdruck in der Vakuumanlage kann während des ionengestützten Beschichtungsprozesses im erforderlichen Maße niedrig gehalten werden.The working pressure in the vacuum system can during of the ion-assisted coating process can be kept as low as necessary.

Zwischen dem Schirm 13 und der Wasserzuführung sowie der Zuführung des positiven Anodenpotentials wird ein dunkler Katodenraum erzeugt, der vor dem Enstehen einer unerwünschten Gasentladung zwischen den Zuführungen und dem Gehäuse der Vakuumkammer (negatives Potential) schützt.A dark cathode space is created between the screen 13 and the water supply and the supply of the positive anode potential, which protects against the occurrence of an undesired gas discharge between the supply lines and the housing of the vacuum chamber (negative potential).

Ausführungsbeispiel IIEmbodiment II

In Figur 3 ist als Ausführungsbeispiel II eine Variante der Ionenquelle nach Ausführungsbeispiel I (gleiche Positionsnummern) dargestellt, bei der eine zweite Magnetspule 15 außerhalb des Gehäuses 1 der Ionenquelle koaxial zur Magnetspule 3 und axial im Bereich der Anode 2 angeordnet ist. Mit dieser Lösung wird das Magnetfeld weiter verstärkt und es ist möglich den technologischen Prozeß der ionengestützten Abscheidung von optischen Mehrfachschichten bei niedrigeren Drücken (bis zweifach) durchzuführen. Die Magnetspule 15 verstärkt insbesondere das Magnetfeld im oberen Bereich der Entladungszone und ermöglicht die zusätzliche Ionisierung des Arbeitsgases.FIG. 3 shows, as embodiment II, a variant of the ion source according to embodiment I (same item numbers), in which a second magnet coil 15 is arranged outside the housing 1 of the ion source coaxially to the magnet coil 3 and axially in the region of the anode 2. With this solution, the magnetic field is further strengthened and it is possible to carry out the technological process of ion-assisted deposition of optical multilayers at lower pressures (up to twice). The magnetic coil 15 in particular amplifies the magnetic field in the upper region of the discharge zone and enables the additional ionization of the working gas.

Claims (2)

Ionenquelle mit einem vorzugsweise zylindrischen Gehäuse (1), in dem eine Anode (2), eine axiale Magnetfeldquelle, insbesondere eine Magnetspule (3), und zwischen beiden ein Blendensystem eines Gasleitsystems angeordnet sind, derart daß die Magnetspule (3) zentrisch am Boden (8) des einen axialen Endes des Gehäuses (1) so angeordnet ist, daß das Magnetfeld zur Anode (2) hin divergiert und die Anode (2) sich außerhalb der Zone des starken Magnetfeldes befindet, wobei das andere axiale Ende des Gehäuses (1) aus einer scheibenförmigen Gehäuseabdeckung (10) mit einer zentrischen Ionenstrahl-Austrittsöffnung (6) besteht, die Anode (2) die Form einer ringförmigen wassergekühlten Rohranode aufweist, deren innerer Durchmesser größer ist als der Durchmesser der dadurch als Blende wirkenden Ionenstrahl-Austrittsöffnung (6), und das Gasleitsystem im Boden (8) oder im Gehäusemantel und nahe der Magnetspule (3) einen Gaseinlaß (7) für ein Arbeitsgas aufweist und das Gasblendensystem aus einem zur Anode (2) gerichteten kreisringförmigem Blendenring (5), der im wesentlichen gasdicht an der inneren Wand des Gehäuses (1) befestigt ist, und aus einer zur Magnetspule gerichteten zentrischen Blendenplatte (4) besteht, und einer Katode (12), die sich außerhalb des Gehäuses (1) und außerhalb der optischen Linie zwischen der Anode (2) und der Ionenstrahl-Austrittsöffnung (6), vorzugsweise auf der Gehäuseabdeckung (10), befindet.Ion source with a preferably cylindrical housing (1), in which an anode (2), an axial magnetic field source, in particular a magnetic coil (3), and an aperture system of a gas control system are arranged between the two, so that the magnetic coil (3) is centered on the bottom ( 8) of one axial end of the housing (1) is arranged such that the magnetic field diverges towards the anode (2) and the anode (2) is outside the zone of the strong magnetic field, the other axial end of the housing (1) consists of a disc-shaped housing cover (10) with a central ion beam outlet opening (6), the anode (2) has the shape of an annular water-cooled tubular anode, the inner diameter of which is larger than the diameter of the ion beam outlet opening (6) which thereby acts as a diaphragm , And the gas guide system in the bottom (8) or in the housing shell and near the solenoid (3) has a gas inlet (7) for a working gas and the gas shutter system m consists of an annular diaphragm ring (5) directed towards the anode (2), which is attached essentially gas-tight to the inner wall of the housing (1) and consists of a central diaphragm plate (4) directed towards the magnetic coil, and a cathode (12) , which is located outside the housing (1) and outside the optical line between the anode (2) and the ion beam outlet opening (6), preferably on the housing cover (10). Ionenquelle nach Anspruch 1, dadurch gekennzeichnet, daß außerhalb des Gehäuses (1) im axialen Bereich der Anode (2) und koaxial zur Magnetspule (3) innerhalb des Gehäuses (1) eine zusätzliche Magnetspule (15) vorhanden ist, wobei die Magnetfelder gleichgerichtet sind und über das Gehäuse (1) zusammenwirken.Ion source according to Claim 1, characterized in that an additional magnetic coil (15) is provided outside the housing (1) in the axial region of the anode (2) and coaxially to the magnetic coil (3) within the housing (1), the magnetic fields being rectified and interact via the housing (1).
EP96107544A 1995-05-16 1996-05-11 Ion source Expired - Lifetime EP0743669B1 (en)

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BY95024295 1995-05-16
BY950242 1995-05-16
DE19531141A DE19531141C2 (en) 1995-05-16 1995-08-24 Ion source
DE19531141 1995-08-24

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109216151A (en) * 2018-08-16 2019-01-15 兰州大学 A kind of built-in antenna type high frequency ion source device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4862032A (en) * 1986-10-20 1989-08-29 Kaufman Harold R End-Hall ion source
EP0541309A1 (en) * 1991-11-04 1993-05-12 Fakel Enterprise Plasma accelerator with closed electron drift

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4862032A (en) * 1986-10-20 1989-08-29 Kaufman Harold R End-Hall ion source
EP0541309A1 (en) * 1991-11-04 1993-05-12 Fakel Enterprise Plasma accelerator with closed electron drift

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"SUPERCONDUCTING MAGNETIC HALL EFFECT ION SOURCE", IBM TECHNICAL DISCLOSURE BULLETIN, vol. 35, no. 3, 1 August 1992 (1992-08-01), pages 345 - 346, XP000326293 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109216151A (en) * 2018-08-16 2019-01-15 兰州大学 A kind of built-in antenna type high frequency ion source device

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DE59602769D1 (en) 1999-09-23
EA000064B1 (en) 1998-04-30
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EA199600050A3 (en) 1996-12-30
EA199600050A1 (en) 1997-03-31

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