DE102008033940B3 - Functional layer quality determining method, involves separately supplying colorant to working gas or plasma beam or flame or together with precursor, where method is implemented as normal pressure plasma method - Google Patents

Abstract

The method involves producing a plasma beam or a flame from a working gas. A precursor material is supplied to the working gas and/or the plasma beam and/or the flame. A reaction product of a precursor is isolated as a marker layer or a functional layer on a substrate (1). A colorant is separately supplied to the working gas or the plasma beam or the flame or together with the precursor. The colorant is dispersed in a fluid e.g. isopropanol, where the method is implemented as a normal pressure plasma method in atmospheric pressure.

Description

The The invention relates to a method for determining a layer quality.

Around the surface properties Different substrates have been influencing for quite some time Coating method in use, in which coating materials are deposited from a gas phase on a surface become. Among other things, between chemical and physical Distinguished gas phase deposits. In the chemical process are usually so-called precursors, precursors of coating materials, by means of energy supply reacted, precursor reaction products passed to the surface and deposited there. The energy supply can, for example, by means of Flame. The flame supplied precursor forms at its thermal conversion of particles, especially nanoparticles that are still Agglomerate in the flame and then settle on the surface. In this way, a homogeneous and dense coating is possible. A different possibility offer so-called low-pressure plasma method in which the precursor in a plasma source or in its proximity to the to be coated surfaces to thin films is implemented.

since some years, so-called normal pressure plasma processes are known, where the surfaces to be coated are not placed in a vacuum Need to become. The particle formation takes place here already in the plasma. The size of the case resulting agglomerates and thus essential properties of Coating can be, inter alia, by the distance of the plasma source from the surface to adjust. The homogeneity the deposited layers is a suitable guide of the Substrate, comparable to that obtained by flame treatment, However, the required energy input is much lower.

The Having deposited by the said method layers usually a very low layer thickness of a few nanometers. In many cases a homogeneous layer thickness is required. To the quality of the layers ensure the layer thickness must be measured.

Analytical layer Methods, mostly spectroscopic, fail in particular geometric features of the coated substrate, for example in internally coated hollow bodies. spectroscopic Investigations (UV-Vis, FT-IR) of round glass or pipe material for Proof of a thin Coating can be carried out in principle under laboratory conditions. Indeed There are measurement errors due to variations of an entry / exit angle or by variations in glass thickness in the region of the coating caused by the coating Measuring signal so on, so that not or only with considerable effort can be determined whether the measured signal of the coating or attributable to any sample variations.

Also The determination of the layer quality by means of reflectometry is known. These However, sets the exact knowledge of the refractive indices of the glass tube and transparent layer ahead. Since the latter at a silicate Internal coating under atmospheric pressure conditions can not be considered constant, this process also shows problems. In addition, the layer thickness determination is to lower layer thicknesses (For example, less than 50 nm) limited.

in the The case of ellipsometric measurements is extraordinarily difficult to put the light beam on the inside coated surface to uncouple from there again.

From the DE 600 24 314 T2 a method is known for determining the thickness of a layer deposited on a substrate, in which a fluorescent component is deposited in the layer, wherein the coating is exposed to light of a wavelength which is suitable for causing the fluorescent component to fluoresce, wherein the fluorescence is detected. The fluorescence intensity of the coating on exposure is related to the coating thickness, so that the coating thickness can be determined.

From the US 2007/0036921 A1 A method for producing a monocrystalline diamond layer on a substrate by means of plasma-assisted CVD (chemical vapor deposition) is known.

Of the The invention is therefore based on the object, a novel method for determining a quality of a layer on a substrate specify the deposited functional layer.

The The object is achieved by a method having the features of claim 1.

advantageous Embodiments of the invention are the subject of the dependent claims.

In a method according to the invention for determining a layer quality of a functional layer deposited on a substrate, a transparent marker layer which contains at least one dye is deposited on the substrate prior to the deposition of the functional layer. Alternatively, at least one dye in the functional layer self-isolated. After depositing the functional layer, the dye is excited by irradiation with light to shine. A light distribution of the excited dye is measured, wherein fluctuations in a light intensity are interpreted as fluctuations of a layer thickness of the functional layer. The method according to the invention can be used in a simple manner, at least in the case of a transparent substrate, without major limitations due to the substrate geometry in order to determine the quality of the functional layer.

The Deposition takes place according to the invention so that from a working gas a plasma jet or a flame is generated, wherein at least a precursor material to the working gas and / or the plasma jet or supplied to the working gas and / or the flame and in the plasma jet or the flame is reacted. On the substrate will be at least a reaction product of at least one of the precursors as a marker layer or functional layer deposited. The dye will either in a liquid Medium dispersed or contained in the nanozeolites. Of the dispersed dye or the nanozeolites with the dye the working gas or the plasma jet or the flame separately or supplied together with the precursor.

According to the invention Process at atmospheric pressure carried out as a normal pressure plasma method. By working at atmospheric pressure becomes a particularly advantageous way a time-consuming process step the evacuation of a process chamber and apparatuses for vacuum generation, such as vacuum pumps and process chamber, saved. This can be done the procedure without big Integrate effort into a process chain, a manufacturing and compensation of the substrate.

In an embodiment In accordance with the invention, a luminescent dye is deposited. The luminescent dyes are in particular phosphorescent and / or fluorescent. Both fluorescence and phosphorescence are forms of luminescence (cold glow). Fluorescence ends after the end of the irradiation relatively quickly (usually within a millionths Second). In the case of phosphorescence, on the other hand, afterglowing can occur over fractions of a second to occur for hours.

As well may be a thermochromic and / or electrochromic and / or photochromic and / or Gasochrom switching dye are deposited. switching Change dyes their color in dependence from a temperature (thermochromic), an electric field or a current flow (electrochromic), an on with light, in particular Light of certain wavelengths (photochromic) or in the presence of a certain gas (gasochrom).

Preferably are deposited with the dye-loaded Nanozeolithe. Nanozeolites are Nanoscale particles of a species-rich family are chemically more complex Silicate minerals, zeolites. These minerals can reach about 40 percent of their Store dry weight of water, which is released when heated becomes. In humid air, the water can be absorbed without affect the structure of the mineral. Zeolites are out a microporous one framework structure formed from AlO4-- and SiO4 tetrahedra. The aluminum and silicon atoms are interconnected by oxygen atoms. This leads to a Structure of uniform Pores and / or channels, in which substances can be adsorbed. Zeolites can therefore be used as sieves, since only such molecules adsorb in the pores, which have a smaller kinetic diameter than the pore openings the zeolite structure. In the present case, the dyes embedded in the pores of the nanozeolites.

Preferably the irradiation is performed with ultraviolet light.

at Dispersing in particular chemically resistant organic dyes used. The dispersed dye is preferably by means of a peristaltic pump into the working gas, the flame or the plasma jet dusted.

When liquid medium For example, water, isopropanol are used to disperse the dyes or the precursor itself in question.

The Deposition of the marker layer and the functional layer can in one flowing transition so be done that results in a gradient layer. As a gradient layer should be understood a layer whose composition is about their Thickness gradually changes. Of the Term is differentiated from neighboring layers with different ones Used properties that have a clear boundary. As well can clearly separated layers are deposited.

The Marker layer is preferably by deposition of silicon dioxide educated.

The method can be used to determine the quality of a coating of a substrate in the form of a hollow body, wherein the marker layer and / or the functional layer is deposited on an inner surface of the hollow body. In this case, a plasma jet or a flame can be generated from a working gas. At least one precursor material is added to the working gas and / or supplied to the plasma jet and / or the flame and reacted in the plasma jet or the flame. At least one reaction product of at least one of the precursors is deposited on the inner surface of the hollow body and / or on at least one layer arranged on the inner surface, so that the marker layer and / or the functional layer is formed. The plasma jet or the flame are introduced through a first opening of the hollow body.

Preferably is through a second opening of the hollow body the plasma jet or the flame and / or reaction gases of the plasma jet or sucked off the flame.

The Extraction at the second opening allows a particularly homogeneous coating over the entire length of Inner surface.

In front the deposition can be carried out an activation process, wherein the substrate with the plasma jet or the flame without supplying a Precursor material is treated. This will clear the surface of the Substrate cleaned and activated, resulting in better adhesion subsequently applied Layers results.

Farther Can the first coating directly following a manufacturing process the substrate in which the substrate was formed under heat, occur. As a result, the activation step can be saved.

Favorable The hollow body rotates during the Coating process around a long axis to a homogeneous activation or coating the inner surface of the hollow body to achieve.

The homogeneity The activation or coating can also be achieved by a rotation a plasma burner or a flame burner can be achieved.

Preferably is an outer electrode the plasma burner or the flame burner designed in such a way that he or she passes through the first opening in the direction of the longitudinal axis of the hollow body introduced can be.

Farther is through a suction at the second opening of the hollow body of the Plasma jet or the flame passed through the entire hollow body, what a homogeneous activation or coating in the longitudinal direction of the hollow body allows.

Of the Coating process includes one or more coating passes which the outer electrode the plasma burner or the flame burner is inserted into the hollow body and in the longitudinal direction is moved so that the hollow body one or more times in a row from the inside is coated.

Especially becomes a transparent hollow body coated. The hollow body or the substrate is for example made of one of the substances glass, plastic, Metal and ceramics formed.

Of the transparent hollow body can a syringe body be made of glass.

A Temperature of the substrate is for example in a range of 20 ° C to 200 ° C, preferred 20 ° C to 120 ° C, especially preferably 20 ° C up to 80 ° C.

The Method is not limited to the coating of syringe bodies. Much more It can also be for other hollow bodies, in particular tubes and other endless materials of any size, for example for pipelines, be used.

Especially for coating pipes and other continuous material, the Working gas with the precursor introduced into the hollow body and the plasma in the hollow body by means of outside of the hollow body in the hollow body injected energy ignited become.

The ignition of the plasma, for example, by means of high-frequency excitation inductively or capacitively or by means of microwave radiation.

With the method can in the layer, for example, at least one oxide and / or a nitride and / or an oxynitride of at least one of the elements silicon, titanium, aluminum, Molybdenum, Tungsten, vanadium, zirconium or boron are deposited. For the deposition of silicon, titanium and / or aluminum oxide layers are preferred silicon, titanium and / or organoaluminum compounds as Precursors used. Such layers are especially useful as barrier protection layers or scratch-resistant coatings.

These Precursors can in solid, liquid and / or gaseous Form, with solid and liquid precursors before the introduction be converted into the working gas or the plasma jet expediently in the gaseous state.

Preferably, silver-containing nanoparticles and / or silver as nanoparticles may be part of a precursor. In this way, for example, SiO ₂ layers can be formed with silver-containing nanoparticles with which a bactericidal layer can be realized.

One Throughput of the working gas and / or the precursor is preferred variable and controllable and / or adjustable.

Farther The speed with which the plasma torch or the flame burner in the hollow body introduced and being moved, being variable and controllable and / or controllable. In addition to the throughput of the working gas and / or the precursor is so another means for influencing the layer properties, such as the layer thickness available. By a suitable choice these process parameters and the precursors used are, for example the following properties of the substrate can be selectively changed: scratch resistance, self-healing ability, Reflection behavior, transmission behavior, refractive index, transparency, Light scattering, electrical conductivity, Friction, adhesion, hydrophilicity, hydrophobicity, oleophilicity, oleophobicity, surface tension, Surface energy, anti-corrosive effect, dirt-repellent effect, self-cleaning ability, photocatalytic behavior, anti-stress behavior, wear behavior, chemical resistance, biocidal behavior, biocompatible behavior, antibacterial behavior, electrostatic Behavior, electrochromic activity, photochromic Activity, and gasochromic activity.

Especially at least one of the deposited layers is preferred as Diffusion barrier opposite at least one alkali element, for example sodium or potassium, and / or opposite at least one alkaline earth element, for example magnesium or Calcium, and / or opposite Boron and / or in particular opposite Tungsten running.

Farther At least one of the deposited layers provides a diffusion barrier across from at least one of the substances oxygen, water, water vapor and / or organic solvents, in particular of plastics, dar.

When Working gas may be a gas or aerosol, preferably air, oxygen, Nitrogen, noble gases, hydrogen, carbon dioxide, gaseous hydrocarbons, Ammonia or a mixture of at least two of the aforementioned gases be used. Ammonia, for example, is suitable for the formation of Nitrides and can have a catalytic effect in the implementation of Having precursors.

One embodiment The invention will be explained in more detail below with reference to a drawing.

In this shows:

1 a schematic representation of a device for internal coating of a hollow body by means of a plasma torch.

1 schematically shows an apparatus for internal coating of a substrate 1 in the form of a hollow body with a suction device 2 and a plasma torch 3 , The plasma torch 3 will be in a first opening 1.1 in the longitudinal direction of the substrate 1 introduced. The suction device 2 is at a second opening 1.2 of the substrate 1 connected. It is through the first opening 1.1 of the substrate 1 a plasma is introduced under atmospheric pressure and the plasma or a reaction gas of the plasma through the second opening 1.2 of the substrate 1 aspirated.

To determine a layer quality of one on the substrate 1 deposited functional layer is a transparent marker layer on the substrate before the deposition of the functional layer 1 deposited, which contains at least one dye. Alternatively, at least one dye is deposited in the functional layer itself. After depositing the functional layer, the dyes are excited by irradiation with light to shine. A light distribution of the excited dyes is measured, wherein fluctuations in a light intensity are interpreted as fluctuations of a layer thickness of the functional layer.

Preferably the irradiation is performed with ultraviolet light.

The Dyes are in particular phosphorescent and / or fluorescent.

The Deposition of the marker layer and the functional layer can in one flowing transition so be done that results in a gradient layer. Likewise, you can be clear separate layers are deposited.

The Marker layer is preferably by deposition of silicon dioxide educated.

Except a hollow body can in the same way, a differently shaped substrate 1 be coated.

In another embodiment, instead of a plasma torch 3 a flame burner for internal coating of the substrate 1 be used.

Before a coating process, an activation process may take place, in which the plasma jet without the introduction of a precursor material into the interior of the substrate 1 is introduced.

Furthermore, a first inner coating directly following a Herstellungspro zess of the substrate 1 in which the substrate 1 was formed under heat, take place.

In one embodiment of the invention, the substrate 1 in a sample rotation device 4 be held so that the substrate 1 rotated about a longitudinal axis during the coating process.

Furthermore, the plasma torch 3 Be performed to rotate about a longitudinal axis.

Preferably, an outer electrode of the plasma torch 3 configured such that it passes through the first opening 1.1 of the substrate 1 in the direction of the longitudinal axis of the substrate 1 can be introduced.

The coating process may include one or more coating passes involving the outer electrode of the plasma torch 3 in the substrate 1 is inserted and moved in the longitudinal direction, so that the substrate 1 one or more times in a row from the inside is coated.

It can be substrates 1 from one of the substances glass, plastic, metal and ceramic, in particular syringe body made of glass, are coated.

A temperature of the substrate 1 is in this coating process in a range of 20 ° C to 200 ° C, preferably at 20 ° C to 120 ° C, more preferably at 20 ° C to 80 ° C.

With the method can in the functional layer and / or the marker layer, for example, at least an oxide and / or a nitride and / or an oxynitride of at least one of the elements silicon, titanium, aluminum, molybdenum, tungsten, vanadium, zirconium or boron are deposited. For the deposition of silicon, titanium and / or aluminum oxide layers are preferably silicon, titanium and / or organoaluminum Compounds used as precursors.

When Working gas may be a gas or aerosol, for example air, oxygen, Nitrogen, noble gases, hydrogen, carbon dioxide, gaseous hydrocarbons, Ammonia or a mixture of at least two of the aforementioned gases be used.

The suction device 2 is optional and not mandatory for the procedure. It can also be hollow body 1 coated, which have only the first opening and are otherwise closed. Similarly, substrates can be coated, not as a hollow body 1 are formed.

The process can also be used for other hollow bodies 1 , in particular tubes and other endless materials of any size, for example, for pipelines are used.

In particular, for the coating of pipes and other endless material, the working gas with the precursor in the hollow body 1 introduced and the plasma in the hollow body 1 by means of outside of the hollow body 1 in the hollow body 1 coupled energy to be ignited.

The ignition of the plasma, for example, by means of high-frequency excitation inductively or capacitively or by means of microwave radiation.

Of the Dye can be a luminescent dye, in particular a phosphorescent and / or fluorescent dye.

As well may be a thermochromic and / or electrochromic and / or photochromic and / or Gasochrom switching dye are deposited.

Preferably are deposited with the dye-loaded Nanozeolithe.

The Deposition can be made so that a working gas from a plasma jet or a flame is generated, wherein at least one precursor material the working gas and / or the plasma jet or the working gas and / or fed to the flame and in the plasma jet or the flame is reacted. On the substrate is at least one reaction product at least one the precursors deposited as a marker layer or functional layer. The dye is either dispersed in a liquid medium or is contained in the nanozeolites. The dispersed dye or the Nanozeolithe with the dye are the working gas or the Plasma jet or flame separately or together with the precursor fed.

alternative other coating methods are possible to deposit the dye, so the shift quality can be evaluated.

at Dispersing in particular chemically resistant organic dyes used. The dispersed dye can by means of a peristaltic pump into the working gas, the flame or the plasma jet are dusted.

The Method can be carried out at atmospheric pressure in particular as normal pressure plasma method.

When liquid medium For example, water, isopropanol are used to disperse the dyes or the precursor itself in question.

1

substratum

1.1

first opening

1.2

second opening

2

suction

3

plasma torch

4

Sample rotation means

Claims (21)

Method for determining a quality of a layer on a substrate ( 1 ) deposited functional layer, in which - either before the deposition of the functional layer, a transparent marker layer on the substrate ( 1 ) is deposited, which contains at least one dye - or in which at least one dye is deposited in the functional layer, wherein at least one dye after the deposition of the functional layer is excited by irradiation with light to illuminate, wherein a light distribution of the excited dye is measured Fluctuations in a light intensity are interpreted as fluctuations in a layer thickness of the functional layer, characterized in that a plasma jet or a flame is generated from a working gas, wherein at least one precursor material is supplied to the working gas and / or the plasma jet or the working gas and / or the flame and in the plasma jet or the flame is reacted, wherein on the substrate ( 1 ) at least one reaction product of at least one of the precursors as a marker layer or functional layer is deposited, wherein the dye is supplied to the working gas or the plasma jet or the flame separately or together with the precursor, wherein the process is carried out at atmospheric pressure as normal pressure plasma process. Method according to claim 1, characterized in that that a luminescent dye is deposited. Method according to one of claims 1 or 2, characterized that a thermochromic and / or electrochromic and / or photochromic and / or Gasochrom switching dye is deposited. Method according to one of the preceding claims, characterized characterized in that deposited with the dye Nanozeolithe deposited become. Method according to one of claims 1 to 4, characterized that the dye is in a liquid Medium is dispersed. Method according to claim 5, characterized in that that as a liquid Medium water or isopropanol is used. Method according to one of the preceding claims, characterized characterized in that the irradiation is carried out with ultraviolet light. Method according to one of the preceding claims, characterized characterized in that phosphorescent and / or fluorescent Dyes are used. Method according to one of the preceding claims, characterized characterized in that the deposition of the marker layer and the functional layer in a flowing transition so that there is a gradient layer. Method according to one of the preceding claims, characterized in that as substrate ( 1 ) a hollow body is used, wherein the marker layer and / or the functional layer are deposited on an inner surface of the hollow body, wherein the plasma jet or the flame or the working gas through a first opening ( 1.1 ) of the hollow body is introduced. A method according to claim 10, characterized in that the plasma jet or the flame and / or reaction gases of the plasma jet or the flame through a second opening ( 1.2 ) are sucked out of the hollow body. Method according to one of claims 1 to 11, characterized in that before the deposition, an activation process is carried out in which the substrate ( 1 ) is treated with the plasma jet or the flame without supplying a precursor material. Method according to one of claims 1 to 11, characterized in that the deposition directly after a manufacturing process of the substrate ( 1 ), in which the substrate ( 1 ) was formed under heat, takes place. Method according to one of claims 10 to 13, characterized that the hollow body during the Coating process about a longitudinal axis is rotated. Method according to one of claims 10 to 14, characterized in that a plasma burner emitting the plasma stream ( 3 ) or a flame burner emitting flame is rotated about a longitudinal axis during the coating process. Method according to one of claims 10 to 15, characterized in that an outer electrode of a plasma torch emitting the plasma stream ( 3 ) or a flame-emitting flame burner is used, which is designed such that he / she through the first opening ( 1.1 ) is insertable in the direction of the longitudinal axis of the hollow body. Method according to one of claims 10 to 16, characterized in that the coating process comprises one or more coating passes, in which the outer electrode of the plasma torch ( 3 ) or the flame burner is introduced into the hollow body and moved in its longitudinal direction, so that the hollow body is coated one or more times in succession from the inside. Method according to one of the preceding claims, characterized in that a temperature of the substrate ( 1 ) is in a range of 20 ° C to 200 ° C. Method according to one of claims 10 to 18, characterized that as a hollow body a tube or a continuous material is coated. Method according to one of claims 10 to 19, characterized that the working gas is introduced into the hollow body with the precursor and the plasma in the hollow body by means of outside of the hollow body in the hollow body injected energy ignited becomes. Method according to claim 20, characterized in that that the plasma by means of high frequency excitation inductive or capacitive or ignited by microwave radiation.