DE102007049929B4 - Inner coated hollow waveguides, process for their preparation and their use - Google Patents

Abstract

Internal coated hollow fiber waveguide, the
a) a channel structure and
b) an inner coating on the inner surface of the channel structure
wherein the surface of the inner coating facing the channel interior has a height of less than 50 nm.

Description

The invention relates to internally coated hollow optical waveguides which are particularly suitable for guiding, shaping and amplifying electromagnetic waves or particle radiation, to processes for their production and to the use of the internally coated hollow optical waveguides.

X-ray radiation plays an important role in various fields of technology, such as medicine, structural analysis and materials science. Due to the desire for increasingly better resolution capabilities of analytical systems or for further miniaturization of structures, the use of particularly short-wavelength, hard X-ray radiation is becoming increasingly important. As a result, systems are increasingly needed to guide, shape, and amplify such radiation.

For high-energy radiation with wavelengths below 100 nm, conventional lenses are not suitable. Instead, special systems, in particular toroidal concave mirrors, Fresnel zone plates and capillary optics are used in the art for guiding and shaping such radiation. In this case, capillary optics over the other systems, among other things, the advantages of a technologically less expensive and therefore cheaper production, the usability of a larger solid angle range of the radiation used and the ability to flexibly guide the radiation, for example, around obstacles, as it is needed especially for medical applications , on.

However, the inherent reflectivity for high energy radiation in the materials commonly used to make hollow fiber waveguides, such as glass, is low. For guiding, shaping and amplifying, for example, EUV radiation and weak X-radiation, internally coated hollow optical waveguides have therefore been used.

From the US 5,130,172 A For example, a method of metal plating surfaces by chemical vapor deposition or gas phase laser photoablation from a volatile organometallic compound is known.

DE 198 52 722 C1 describes a process for the interior coating of monocapillaries as well as the use of coated monocapillars or bundles of coated monocapillaries for certain catalytic and optical applications.

However, it has been shown that internal coatings of hollow optical waveguides obtainable according to the known methods do not have sufficient quality for many optical applications. Due to insufficient X-ray optical properties such hollow waveguides can not be used in particular for hard X-radiation. For this reason hollow-lead waveguides made of lead glass have been used to guide, shape and amplify hard X-ray radiation. However, it has been found that such glasses are very difficult to work and have only a short life. For example, intensity losses of more than 50% were observed when using hollow lead waveguides made of lead glass for amplification of hard X-ray radiation after 5000 hours of operation compared to the intensities measured at the beginning of use.

There is therefore a need for further systems for guiding, shaping and amplifying electromagnetic waves or particle radiation, which have an improved usability from a technical and economic point of view and in particular are also suitable for use with hard X-radiation.

This object is achieved by the internally coated hollow waveguide according to one of claims 1 to 14 and 40. The invention also relates to a method for producing an internally coated hollow optical waveguide according to claims 15 to 39 and to the use of an internally coated hollow optical waveguide according to one of claims 41 and 42.

The inner coated hollow optical waveguide according to the invention is characterized in that it comprises (a) a channel structure and (b) an inner coating on the inner surface of the channel structure, wherein the surface of the inner coating facing the channel interior has a height of less than 50 nm.

Inner waveguide waveguides according to the invention exhibit significantly better optical, in particular X-ray optical properties compared to known waveguides. Surprisingly, in contrast to known internally coated systems, the hollow waveguides according to the invention are also suitable for guiding, shaping and amplifying hard X-radiation. In this case, they have a significantly improved long-term stability compared to the previously used for this purpose uncoated hollow fiber waveguides made of lead glass.

The term "channel structure" here comprises both monocanal structures and polychannel structures and denotes a structure that consists of one or more spatially arranged at regular intervals, through and consists of open channels at the ends. Examples of mono-channel structures are monocapillaries. Examples of multi-channel structures are polycapillaries, compound lenses made of individual mono- and / or polycapillaries, monolithic lenses made of individual mono- and / or polycapillaries, photonic crystals and monolithic integral microlenses.

The inner diameter of a single channel of the channel structure is usually in the range of 1 nm to 10 mm. The internal diameter is preferably less than 1000 μm, in particular less than 100 μm.

For example, in general, the inner diameters of the channels in compound lenses are made of monocapillaries in the range of 1 to 10 mm, in monolithic lenses made of monocapillaries in the range of 0.1 to 1 mm, in compound lenses made of polycapillaries in the range of 10 to 100 microns , in monolithic lenses made of polycapillaries in the range of 1 to 10 microns and in monolithic integral microlenses in the range of 0.3 to 1 micron.

Polycapillaries are usually monolithic structures having a plurality of channels, which channels are of substantially equal length and usually have a length to internal diameter ratio of at least about 100: 1, preferably at least about 1000: 1. Polycapillaries may contain, for example, more than 10 ³ to more than 10 ⁶ channels having internal diameters of, for example, less than 1 mm to less than 1 μm.

Photonic crystals are artificial periodic structures of a dielectric (eg glass) with specific optical properties. In addition to glass, other materials can be used. Photonic crystals are used, for example, in optical metrology, communications and life sciences and are described in VP Bykov, "Spontaneous emission in a periodic structure", Soviet Physics JETP, American Institute of Physics, New York 1972, 35, 269 and K Busch et al. (Ed.), "Photonic Crystals - Advances in Design, Fabrication, and Characterization", Wiley-VCH, 1st Edition, 2004.

Monolithic integral microlenses are very largely miniaturized multi-channel structures, which may, for example, have channels with internal diameters of about 0.3 to 1 μm.

Various mono- and multi-channel structures are commercially available for example from the IFG - Institute for Scientific Instruments GmbH, Berlin-Adlershof, Germany, the universities Antis Europe GmbH, Georgsmarienhütte Germany and the X-Ray Optical Systems, Inc., (XOS ^®), East Greenbush, NY, USA available.

Multi-channel structures often have a relatively thin channel wall in direct comparison to their outer wall. This channel wall is significantly thinner than the outer wall of monocapillaries, as it serves only for the separation of the channels and has no structure-supporting function as in monocapillaries. This is possible with multi-channel structures due to their monolithic structure.

In a preferred embodiment, the channel structure consists of an inorganic material or a plastic. Suitable inorganic materials include carbon, for example, nanoporous carbon and carbon nanotubes (CNT), silicon, glass, ceramics and metal, for example, steel and aluminum. Examples of suitable plastics are in particular silicones. Particularly preferably, the channel structure consists of glass. Examples of suitable types of glass are in particular quartz glass, Duranglas and N16B glass (borosilicate glasses), quartz glass and Duranglas are preferred.

Furthermore, it is preferred that the channel structure contains heat conducting or Wärmeleitdrähte, z. For example, by introducing metals, in particular heat conducting wires, into the channel structure during the production of the channel structure (for example in the drawing process). This ensures an isotropic temperature distribution within the channel structure, which has a positive effect on thermal coating processes (see below) as well as on applications of the hollow waveguides according to the invention at higher temperatures.

The inner coating usually contains a non-carbon element from the second to fifth main group or a subgroup of the Periodic Table of the Elements. The inner coating preferably contains an element selected from the group consisting of Be, Ni, Pt, Cu, Pd, Ag, W, Re, Ir, Os, Au, Pb, Bi and U, where the elements Ni, Ag, Au, W , Pb, Pt, Bi and U are particularly preferred.

In another preferred embodiment, the inner coating contains a metal having an atomic number Z> 27, in particular Z> 40, most preferably Z> 71.

It is particularly preferred that the inner coating is a metallic coating which is substantially free of other elements, in particular substantially free of carbon.

The inner coating can consist, for example, of metal layers and / or metal particles, particularly preferably of amorphous metal layers and / or of amorphous metal particles, in particular of amorphous metal layers. It is particularly preferred that the inner coating is in the form of a closed layer layer, in particular a Franck-van der Merve growth layer.

The inner coatings of the invention are typically very smooth and are characterized by low corrugation, in particular by low rms surface roughness and low height.

The term "corrugation" here denotes a measure of the surface quality, which is essentially determined by the rms surface roughness, the height of the surface and the degree of coverage of the coating. In this case, low corrugation is promoted in particular by a low rms surface roughness, a low height and a high degree of coverage.

The term "rms surface roughness" here refers to the root-mean-square roughness of the surface.

The term "height" with respect to a surface here refers to the value at which 95% of the heights of the surface are less than or equal to this value.

As used herein, the term "degree of coverage" with respect to a coating means the proportion of a sub-coating surface covered by the coating.

In a preferred embodiment, the surface of the inner coating facing the channel interior has an rms surface roughness of less than 10 nm, in particular less than 5 nm, most preferably less than 2 nm. The height of the surface of the inner coating facing the channel interior is preferably less than 15 nm, in particular less than 8 nm, most preferably less than 4 nm. The degree of coverage of the inner coating is preferably at least 95%, in particular at least 98%, most preferably at least 99 %.

When the inner coating is composed of particles, the particles usually have a very narrow particle size distribution. It is preferred that the particles are monodisperse. Particularly preferably, the inner coating contains particles having a particle size distribution in which the standard deviation of the particle size is less than 20%, in particular less than 10%, most preferably less than 5% of the mean particle size.

In general, the thickness of the inner coating can be varied within wide ranges depending on the inner diameter of the channel structure. For example, an inner coating according to the invention may have a thickness in the range from 1 to 1000 nm. The inner coating according to the invention preferably has a thickness in the range of 10 to 250 nm, in particular 50 to 150 nm, most preferably 80 to 120 nm. It has been found that internal coatings of this thickness are particularly suitable for optical properties.

The invention also relates to a method for producing the internally coated hollow waveguide according to the invention. This method is characterized in that the inner coating is deposited in the channel structure by a photolytic process (for example laser coating), a plasma technology process or a gas-phase process.

Examples of gas-phase processes are chemical vapor deposition (CVD) or chemical vapor infiltration (CVI). In particular, methods are suitable in which the inner coating by chemical vapor deposition of organometallic compounds, such as chemical vapor deposition of organometallic compounds (OMCVD), chemical vapor infiltration of organometallic compounds, such as chemical vapor infiltration of organometallic compounds (OMCVI), or gas phase epitaxy of elemental organic compounds, such as gas phase epitaxy of organometallic compounds (OMVPE), are deposited in the channel structure. The term "elemental organic compound" refers in particular to a compound which contains a non-carbon element from the second to fifth main group or a subgroup of the Periodic Table of the Elements and organic groups and / or carbonyl which chemically directly and / or via an element of fifth or sixth main group are bound to the respective element. Suitable organometallic compounds for gas-phase processes are in particular complex or coordination compounds which contain an organic ligand and / or carbonyl. Complex or coordination compounds which contain a ligand selected from the group consisting of carbonyl, hexafluoroacetylacetonato and acetylacetonato are preferred.

By coating processes using high temperatures or energies, such as physical vapor deposition or chemical Gas phase deposition, in particular the thin channel wall of multi-channel structures can be destroyed due to the effect of energy. The chemical vapor deposition of organometallic compounds, in particular the chemical vapor deposition of organometallic compounds (OMCVD), a coating method is provided here, with the coatings of channel structures at relatively low temperatures can be carried out without damaging or destroying them.

• (a) Evakuieren der Kanalstruktur, wobei zwischen den Enden der Kanalstruktur ein Druckgradient aufgebaut wird,
• (b) Einstellen der gesamten Kanalstruktur auf eine konstante Temperatur im Bereich von 273 K bis 2073 K, bevorzugt 293 K bis 873 K, am meisten bevorzugt 373 K bis 723 K, die 50 K bis 150 K, bevorzugt 80 K bis 120 K unterhalb der Zersetzungstemperatur des Precursormaterials liegt,
• (c) Verdampfen eines Precursormaterials und Transport des Precursormaterials durch die Kanalstruktur durch den Druckgradienten,
• (d) Abscheiden einer Beschichtung aus dem Precursormaterial durch lokal begrenzte Zufuhr von Energie.

According to the invention, the method for producing the internally coated hollow waveguides comprises the steps

• (a) evacuating the channel structure, establishing a pressure gradient between the ends of the channel structure,
• (b) adjusting the total channel structure to a constant temperature in the range of 273K to 2073K, preferably 293K to 873K, most preferably 373K to 723K, 50K to 150K, preferably 80K to 120K below the decomposition temperature of the precursor material is,
• (c) evaporating a precursor material and transporting the precursor material through the channel structure through the pressure gradient,
• (D) depositing a coating of the precursor material by locally limited supply of energy.

To carry out this process, the channel structure is first connected in a gastight manner to a vacuum system by means of a temperature-stable adhesive, preferably a two-component adhesive. Examples of suitable two-component adhesives are epoxy adhesives, which are temperature-stable up to about 450 K, and silicone adhesives, which are temperature-stable up to about 570 K. Before the further process steps, the adhesive is cured for a sufficient time.

Optionally, prior to step (a), the inner surface of the channel structure may be activated. This activation of the inner surface can be carried out, for example, by passing molecular oxygen, preferably at a temperature in the range from 480 K to 773 K. By activating the inner surface of their adsorption capacity is significantly improved, thus significantly increasing the affinity of the coating material against the inner surface. Therefore, activating the inner surface can also positively influence the type of growth behavior of the coating on the inner surface.

Further, prior to step (a) and optionally before activation of the interior surfaces, the channel (s) of the channel structure may be cleaned. This can be done, for example, by plasma treatment, e.g. B. by an inductively or capacitively generated plasma, chemical processes and / or evacuation with simultaneous annealing. In particular, the cleaning of the channel (s) of the channel structure can be effected by evacuation at a pressure below 10 ^-3 mbar with simultaneous annealing, preferably at a temperature in the range of 473 K to 773 K. By cleaning the channel (s), any organic contaminants of the inner surface, above all, can be removed by combustion to carbon dioxide, thus achieving improved adhesion of the inner coating to the inner surface.

Prior to step (a), optionally before activation of the inner surface (s) and optionally before or after cleaning of the channel (s), thermal smoothing of the inner surface (s) of the channel (s) of the channel structure may occur. In particular, the thermal smoothing of the inner surface (s) of the channel (s) can be accomplished by heating to a temperature in the range of 473K to 2073K, preferably 573K to 1473K, 50K to 1500K, especially 100K to 1000K , preferably 150 K to 300 K below the softening point of the glass is. By thermal smoothing of the inner surface (s), the corrugation of the inner surface can be reduced, which in particular favors the formation of inner layers with low height.

For the transport of the precursor material through the channel structure, a pressure gradient is established between the ends of the channel structure. For this, the channel structure is evacuated from one of its ends. In this case, a minimum pressure of less than 10 ^-2 mbar, preferably less than 10 ^-3 mbar and particularly preferably less than 10 ^-4 mbar is set at this end.

Evaporation of the precursor material can be assisted by using a vacuum system in which the channel structure is evacuated from both ends with different vacuum pumps. Such a vacuum system is for example in DE 198 52 722 C1 described.

In contrast, it is preferred according to the invention that the channel structure is evacuated only from one of its ends. Surprisingly, if the channel structure is evacuated only from one of its ends, a more homogeneous flow behavior of the precursor material is achieved. As a result, an inner coating can be obtained, which is characterized by an extremely low height. In addition, in this embodiment, a smaller amount of foreign material, ie, other material than the precursor material, in particular a smaller amount of oxygen, by the Transported channel structure. As a result, inner coatings of higher quality can be obtained.

The transport of the precursor material through the channel structure can also be assisted by an adjustable carrier gas flow.

Subsequently, the entire channel structure is set to a constant base temperature in the range of 273 K to 2073 K, preferably 293 K to 873 K, most preferably 373 K to 723 K, the 50 K to 150 K, preferably 80 K to 120 K below the Decomposition temperature of the precursor material is. The constant basic temperature can be set, for example, by heating or heating with a heater (eg electric heater or induction furnace) or by coupling in electromagnetic waves (eg microwave or infrared radiation).

The precursor material is vaporized and transported through the channel structure by the pressure gradient, optionally with the assistance of the carrier gas flow. The precursor stream and optionally the carrier gas stream can be preheated to a defined temperature, wherein this temperature is 50 K to 150 K, preferably 80 K to 120 K below the decomposition temperature of the precursor material.

The deposition of a coating from the precursor material takes place by locally limited supply of energy. This energy supply locally sets a temperature which is equal to or greater than the decomposition temperature of the precursor material. A local temperature in the range of 273 K to 2073 K, more preferably 293 K to 873 K, most preferably 423 K to 723 K is preferably set by locally limited supply of energy. The decomposition of the precursor material deposits the inner coating on the inner surface of the channels.

In a preferred embodiment, the duration of the supply of locally limited energy in step (d) is selected so that an inner coating having a thickness in the range of 10 to 250 nm, in particular 50 to 150 nm, most preferably 80 to 120 nm, is deposited. Surprisingly, can be obtained by such a simple choice of coating time interior coatings, which are characterized by a particularly low corrugation, low surface roughness and low height and are particularly suitable for optical applications.

Preferably, the locally limited supply of energy takes place thermally and / or photochemically, in particular by a heat or radiant heater, an oven, a laser, microwave radiation and / or a plasma. In a particularly preferred embodiment, the locally limited supply of energy by combining a thermal and a photochemical supply of energy, in particular by a combination of heating or heating with a heater (eg electric heater or induction furnace) or by coupling electromagnetic waves ( eg microwave or infrared radiation) with irradiation (eg with a laser).

The adjustment according to the invention of the channel structure to a constant basic temperature below the decomposition temperature of the precursor material makes it possible to reduce the local additional energy supply necessary for the coating. Surprisingly, this allows a much better controllable deposition behavior of the inner coating can be realized, which allows the formation of closed layer layers with extremely low height.

Optionally, by subsequent passage of a gas, a chemical, physical and / or morphological change of the coating can be effected. Examples of suitable gases are oxygen, hydrogen or nitrogen. For example, contaminants may be removed by combustion, for example from organic residues to carbon dioxide and water.

The method for producing the internally coated hollow waveguides according to the invention preferably comprises performing an in-situ process analysis. Based on the process analysis, the production process can be controlled, so that particularly advantageous internal coatings are obtained. Process analysis can be carried out, for example, by optical measurement methods, by online mass spectrometry or by taking gas samples and by gas chromatography.

An in-situ determination of the coating thickness can be carried out in particular by laser transmission. For this purpose, the transmission of laser radiation, for example a red laser with a wavelength range of 660 to 680 nm, in the direct beam passage through the hollow waveguide is determined by measuring the photocurrent caused in a photodiode. The measured photocurrents are corrected on the basis of reference values which are obtained in the same arrangement in each case without a hollow-fiber waveguide or with the uncoated hollow-waveguide. Scanning electron micrographically determined coating thicknesses are correlated with the photocurrents obtained for the respective coating thicknesses. The correlation thus obtained makes it possible to obtain a non-destructive coating in the ongoing coating process make quantitative determination of the coating thickness and so to control the production process of the inner coated hollow optical waveguide according to the invention to achieve a certain coating thickness.

A control of the production process can also or additionally be carried out on the basis of a product analysis of the internally coated hollow optical waveguides produced according to the invention. For this purpose, suitable preparations can be made for carrying out an analysis, for example cross-sections by means of an ultramicrotome for energy-dispersive X-ray measurements, in particular a two-dimensional one. X-ray mappings, as well as for trans-electron microscopic or scanning electron microscopic investigations. As a result, the change in the characteristics of the inner coatings caused by the choice of the process parameters can be investigated and used to further control the production process.

Various precursor materials can be used in the process according to the invention. It is advantageous if the precursor material is a sublimable material, wherein a sublimable at room temperature material is preferred. It is also advantageous if the precursor material is stable to air.

Preference is given to a precursor material which contains an element other than carbon from the second to fifth main group or a subgroup of the Periodic Table of the Elements and organic groups and / or carbonyl which are chemically directly and / or via an element of the fifth or sixth main group to the respective element are bound. In particular, the precursor material may be an organometallic compound having at least one metal-carbon bond, or a complex or coordination compound containing an organic ligand and / or carbonyl. Complex or coordination compounds which contain a ligand selected from the group consisting of carbonyl, hexafluoroacetylacetonato and acetylacetonato are preferred.

In a preferred embodiment, the precursor material comprises an element selected from the group consisting of Be, Ni, Pt, Cu, Pd, Ag, W, Re, Ir, Os, Au, Pb, Bi, and U, wherein the elements Ni , Ag, Au, W, Pb, Pt, Bi and U are particularly preferred. Particularly preferred is a precursor material which is selected from the group consisting of
Bis (1,1,1,5,5,5-hexafluoro-2,4-pentanedionato) palladium (II),
tetracarbonylnickel,
nickelocene,
2,2,6,6-tetramethyl-3,5-heptandionatosilber (I),
Tris (2,2,6,6-tetramethyl-3,5-heptanedionato) bismuth (III),
tetraethyl lead,
Bis (2,2,6,6-tetramethyl-3,5-heptanedionato) lead (II),
Uranium hexafluoride,
uranocene,
uranium acetate,
tungsten hexacarbonyl,
Dimethyl (hexafluoroacetylacetonato) gold,
Tetrakis (triphenylphosphine) platinum (0)
Bis (hexafluoroacetylacetonato) platinum (II),
Bis (acetylacetonato) platinum (II),
Dimethyl (1,5-cyclooctadiene) platinum (II),
Methyl (triphenylphosphine) gold (I) and
Bis (1,1,1,5,5,5-hexafluoro-2,4-pentanedionato) -lead (II).

The invention also relates to internally coated hollow optical waveguides obtainable by the method described above. Surprisingly, the inner coatings of such internally coated hollow optical waveguides are characterized by a special surface morphology. Without being limited to a particular theory, it is assumed that homogeneous layer layers with low corrugation, low surface roughness and low height, which are composed of particles which have a monodisperse particle size distribution and a special, in particular cut-off, in dimension, are formed by the method according to the invention have upset perpendicular to the coating surface shape. These internally coated hollow waveguides are particularly advantageous for optical applications. Preferred embodiments of these internally coated hollow optical waveguides have materials, coating thicknesses, surface roughnesses, heights and / or particle size distributions as defined above.

The invention also relates to the use of the inner coated hollow waveguide according to the invention. In particular, the invention relates to the use of the inner coated hollow optical waveguides according to the invention for shaping, guiding, focusing and amplifying electromagnetic waves or particle radiation, in particular of microwaves, the wavelength range of 100 cm to 1 mm being particularly preferred, of visible light, the wavelength range from 380 to 750 nm is particularly preferred, of UV radiation, wherein the wavelength ranges from 50 to about 190 nm (VUV range) and 1 to 50 nm (EUV range) are particularly preferred, laser radiation, X-rays and particle radiation (γ- Radiation and neutron radiation).

Particularly preferred are the low-energy range of the X-radiation with an energy of 0.124 to 1.24 keV (corresponding to a wavelength of 1 to 10 nm); the higher energy range of the X-radiation with an energy of 1.24 to 12.4 keV (corresponding to a wavelength of 0.1 to 1 nm), in particular the discrete wavelengths of the Cu Kα radiation (8 keV); and the high-energy region of the X-radiation with an energy of 12.4 to 124 keV (corresponding to a wavelength of 0.01 to 0.1 nm), in particular the discrete wavelengths of MoKα radiation (17 keV). Particularly preferred is the range of X-rays with an energy of 15 to 30 keV.

Especially in the high-energy range of X-radiation, the wavelength of the radiation to be amplified is smaller than the distance of the atoms in the solid state. Surprisingly, the internally coated hollow optical waveguides according to the invention are also particularly suitable for shaping, guiding, focusing and amplifying electromagnetic waves whose wavelengths are smaller than the rms surface roughness and / or the height of the interior coating facing the channel interior.

Also preferred is the use of the internally coated hollow optical waveguides according to the invention for X-ray lithographic applications such as soft X-ray lithography (SXRL) with 1 to 2 keV or deep x-ray lithography (DXRL) with 4 to 10 keV. Also preferred is the use for X-ray microscopic applications in the spectral range of about 2 to about 4 nm (water window).

A particular advantage of the inner coated hollow optical waveguides according to the invention is their improved long-term stability when used for shaping, guiding, focusing and amplifying electromagnetic waves or particle radiation. In the case of uncoated hollow-fiber waveguides, for example made of lead glass, energy recordings, for example by X-ray exposure, lead in the long term to material damage to the hollow-fiber waveguides and thus to loss of intensity and unusability of the structures. In the inner coated hollow optical waveguides according to the invention, such material damage can be at least largely avoided.

Particular preference is also given to the use according to the invention of internally coated hollow optical waveguides for focusing EUV radiation or X-radiation for (X-ray) lithographic applications, for example in mask exposure for semiconductor production. The use according to the invention of internally coated hollow-fiber waveguides in X-ray-medical procedures, in particular in X-ray endoscopy, is also preferred.

The invention will now be explained in more detail with reference to selected examples.

example 1

A 250 mm long fused silica monocrillet, having a length of 250 mm, an outside diameter of 0.8 mm and an inside diameter of 0.55 mm, was gas-tightly connected to a vacuum system by means of a two-part adhesive at one end and heated several times by simultaneous heating to 650 K and passing 1000 mbar molecular oxygen purified from the inside. Subsequently, a constant basic temperature of the monocapillar structure of 373 K was set. The minimum pressure set by the vacuum system was 10 ^-5 mbar. As precursor W (CO) _{6 was} used. By means of a mobile kiln system, a locally limited temperature of 696 K was set in sections over a period of 120 minutes. Finally, the monocapillar structure was sealed under inert gas conditions.

XRD (X-Ray Diffraction) measurements were carried out with the obtained inner coating ( 1 ). No reflections were measured in the relevant areas. This shows that the resulting coating was amorphous.

The coating thickness of the inner coating was determined by scanning electron microscopy to be 104 nm. The surface morphology of the inner coating was investigated by AFM (Atomic Force Microscopy) ( 2 ). These studies confirmed that an inner coating having very little corrugation was obtained. A closer examination revealed that the surfaces had an rms surface roughness of 1 nm and a height of 1-2 nm.

The internally coated monocapillary was examined by means of X-ray optical measurements in an energy range of 15 to 30 keV. Intensity enhancements of up to more than 80% have been achieved ( 3 ).

Example 2

An N16B 250 mm long, 2 mm OD, 0.5 mm I.D. mono capillary was gas tightly attached to a vacuum system by means of a two-part adhesive at one end and heated several times by simultaneous heating to 650 K and passing 1000 mbar molecular oxygen purified from the inside. Subsequently, a constant basic temperature of the monocapillar structure of 373 K was set. The minimum pressure set by the vacuum system was 10 ^-5 mbar. As precursor W (CO) _{6 was} used. By means of a mobile kiln system, a locally limited temperature of 696 K was set in sections over a period of 120 minutes. Finally, the monocapillar structure was sealed under inert gas conditions.

The internally coated monocapillary was examined by means of X-ray optical measurements in an energy range of 15 to 30 keV. Intensity gains of up to 75% were achieved ( 3 ).

Example 3

A glass polycapillary structure having a length of 50 mm and a maximum outside diameter of 7.20 mm was used which contained about 40,000 channels with a channel internal diameter of 29.5 μm. This polycapillary structure was connected to a vacuum system at one end as in Example 1 and cleaned from the inside. Subsequently, a constant basic temperature of the polycapillary structure of 373 K was set. The minimum pressure set by the vacuum system was 10 ^-5 mbar. As precursor W (CO) _{6 was} used.

By means of a mobile furnace system, a localized temperature of 723 K was set in sections over a period of 118 minutes. The energy supplied via the furnace system and the temperature gradient were kept constant.

Claims (42)

Internal coated hollow fiber waveguide, the a) a channel structure and b) an inner coating on the inner surface of the channel structure wherein the surface of the inner coating facing the channel interior has a height of less than 50 nm. The inside coated hollow optical waveguide according to claim 1, wherein the channel structure is a mono-channel structure or a multi-channel structure. An inner coated hollow optical waveguide according to claim 2, wherein the monochannel structure is a monocapillary. The inside coated hollow fiber waveguide of claim 2, wherein the multichannel structure is selected from the group consisting of polycapillaries, compound lenses made of single mono- and / or polycapillaries, monolithic lenses made of single mono- and / or polycapillaries, photonic crystals, and monolithic integral microlenses. An inner coated hollow optical waveguide according to any one of claims 1 to 4, wherein the channel structure is made of glass. An inner coated hollow optical waveguide according to any one of claims 1 to 5, wherein the channel structure includes thermal conduction wires or heat conduction wires. The inside coated hollow optical waveguide according to any one of claims 1 to 6, wherein the inner coating contains a non-carbon element from the second to fifth main group or a subgroup of the periodic table of the elements. The inner coated hollow optical waveguide according to any one of claims 1 to 7, wherein said inner coating contains a metal selected from the group consisting of Be, Ni, Pt, Cu, Pd, Ag, W, Re, Ir, Os, Au, Pb, Bi and U. , wherein the elements Ni, Ag, Au, W, Pb, Pt, Bi and U are particularly preferred. Inner coated hollow optical waveguide according to one of claims 1 to 8, wherein the inner coating contains a metal having an atomic number Z> 27, in particular Z> 40, most preferably Z> 71. Inner coated hollow optical waveguide according to one of claims 1 to 9, wherein the inner coating of metal layers and / or metal particles, preferably of amorphous metal layers and / or amorphous metal particles, in particular of amorphous metal layers. An inner coated hollow optical waveguide according to any one of claims 1 to 10, wherein the channel interior facing surface of the inner cladding has an rms surface roughness of less than 10 nm, especially less than 5 nm, most preferably less than 2 nm. The inner coated hollow optical waveguide according to any one of claims 1 to 11, wherein the surface of the inner coating facing the channel interior has a height of less than 15 nm, in particular less than 8 nm, most preferably less than 4 nm. An inner coated hollow optical waveguide according to any one of claims 1 to 11, wherein the degree of coverage of the inner coating is at least 95%, more preferably at least 98%, most preferably at least 99%. The inner coated hollow fiber waveguide of any one of claims 1 to 13, wherein the inner coating contains particles having a particle size distribution where the standard deviation of the particle size is less than 20%, more preferably less than 10%, most preferably less than 5% of the mean particle size. An inner coated hollow optical waveguide according to any one of claims 1 to 14, wherein the inner coating has a thickness in the range of 1 to 1000 nm, preferably 10 to 250 nm, especially 50 to 150 nm, most preferably 80 to 120 nm. A method for producing an internally coated hollow optical waveguide according to any one of claims 1 to 15, wherein the inner coating is deposited by a photolytic process, a plasma technology process or a gas-phase process in the channel structure and the steps (a) evacuating the channel structure, establishing a pressure gradient between the ends of the channel structure, (b) adjusting the total channel structure to a constant base temperature in the range of 273K to 2073K, preferably 293K to 873K, most preferably 373K to 723K, 50K to 150K, preferably 80K to 120K below the decomposition temperature of the precursor material is, (c) evaporating a precursor material and transporting the precursor material through the channel structure through the pressure gradient, and (D) depositing a coating of the precursor material by locally limited supply of energy includes. The method of claim 16, wherein the inner coating is deposited by chemical vapor deposition (CVD) or chemical vapor infiltration (CVI) in the channel structure. The method of claim 17, wherein the inner coating is deposited by chemical vapor deposition of organometallic compounds (OMCVD), chemical vapor infiltration of organometallic compounds (OMCVI) or gas phase epitaxy of organometallic compounds (OMVPE) in the channel structure. A method according to any one of claims 16 to 18, wherein prior to step (a) the inner surface of the channel structure is activated. The method of claim 19, wherein activating the inner surface is by passing molecular oxygen, preferably at a temperature in the range of 480 K to 773 K. A method according to any one of claims 16 to 20, wherein prior to step (a) and optionally before activation of the inner surface, the channel (s) of the channel structure are cleaned. The method of claim 21, wherein the cleaning of the channel (s) of the channel structure is performed by plasma treatment, chemical processes and / or evacuation with simultaneous annealing. The method of claim 22, wherein the cleaning of the channel (s) of the channel structure by evacuation at a pressure below 10 ^-3 mbar with simultaneous annealing, preferably at a temperature in the range of 473 K to 773 K occurs. A method according to any of claims 16 to 23, wherein prior to step (a), optionally before activation of the inner surface and optionally before or after cleaning of the channel (s), thermal smoothing of the inner surface of the channel (s) of the channel structure occurs. The method of claim 24, wherein the thermal smoothing of the inner surface of the channel (s) of the channel structure is carried out by heating to a temperature in the range of 473 K to 2073 K, preferably 573 K to 1473 K, which is 50 K to 1500 K, in particular 100 K is up to 1000 K, preferably 150 K to 300 K below the softening point of the glass. Method according to one of claims 16 to 25, wherein the channel structure is evacuated only from one of its ends. Method according to one of claims 16 to 26, wherein in step (a) a minimum pressure of less than 10 ^-2 mbar, preferably less than 10 ^-3 mbar and more preferably less than 10 ^-4 mbar, is set. Method according to one of claims 16 to 27, wherein the transport of the precursor material through the channel structure in step (c) is supported by a carrier gas stream. Method according to one of claims 16 to 28, wherein in step (d) a local temperature in the range of 273 K to 2073 K, preferably 293 K to 873 K, is set. Method according to one of claims 16 to 29, wherein the supply of energy in step (d) by a heat or radiant heater, an oven, a laser, microwave radiation and / or a plasma takes place. A method according to any one of claims 16 to 30, wherein the supply of energy in step (d) is by combination of a thermal and a photochemical supply of energy. The method of any one of claims 16 to 31, further comprising passing a gas for chemical, physical and / or morphological alteration of the coating. The method of any of claims 16 to 32, further comprising performing an in-situ process analysis and process control. A method according to any one of claims 16 to 33, wherein the precursor material is a sublimable material. A method according to any one of claims 16 to 34, wherein the precursor material contains a non-carbon element from the second to fifth main group or a subgroup of the Periodic Table of the Elements and organic groups and / or carbonyl which are chemically directly and / or via an element of fifth or sixth main group are bound to the respective element. A method according to any one of claims 16 to 35, wherein the precursor material is an organometallic compound having at least one metal-carbon bond or a complex or coordination compound containing an organic ligand and / or carbonyl. The method of claim 36, wherein the complex or coordination compound comprises a ligand selected from the group consisting of carbonyl, hexafluoroacetylacetonato and acetylacetonato. A method according to any one of claims 16 to 37, wherein the precursor material comprises an element selected from the group consisting of Be, Ni, Pt, Cu, Pd, Ag, W, Re, Ir, Os, Au, Pb, Bi and U, wherein the elements Ni, Ag, Au, W, Pb, Pt, Bi and U are particularly preferred. The method of any one of claims 16 to 38, wherein the precursor material is selected from the group consisting of Bis (1,1,1,5,5,5-hexafluoro-2,4-pentanedionato) palladium (II), tetracarbonylnickel, nickelocene, 2,2,6,6-tetramethyl-3,5-heptandionatosilber (I), Tris (2,2,6,6-tetramethyl-3,5-heptanedionato) bismuth (III), tetraethyl lead, Bis (2,2,6,6-tetramethyl-3,5-heptanedionato) lead (II), Uranium hexafluoride, uranocene, uranium acetate, tungsten hexacarbonyl, Dimethyl (hexafluoroacetylacetonato) gold, Tetrakis (triphenylphosphine) platinum (0) Bis (hexafluoroacetylacetonato) platinum (II), Bis (acetylacetonato) platinum (II), Dimethyl (1,5-cyclooctadiene) platinum (II), Methyl (triphenylphosphine) gold (I) and Bis (1,1,1,5,5,5-hexafluoro-2,4-pentanedionato) -lead (II). Inner coated hollow optical waveguide obtainable by a method according to one of claims 16 to 39. Use of an internally coated hollow optical waveguide according to one of claims 1 to 15 or 40 or of an internally coated hollow optical waveguide produced according to one of claims 16 to 39 for shaping, guiding, focusing and amplifying electromagnetic waves or particle radiation. Use according to claim 41, wherein the electromagnetic waves are hard X-rays having an energy of more than 12.4 keV, preferably more than 15 keV.

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